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Sample records for internal reflection microscopy

  1. Alignment and calibration of total internal reflection fluorescence microscopy systems.

    Science.gov (United States)

    Toomre, Derek

    2012-04-01

    Live cell fluorescent microscopy is important in elucidating dynamic cellular processes such as cell signaling, membrane trafficking, and cytoskeleton remodeling. Often, transient intermediate states are revealed only when imaged and quantitated at the single-molecule, vesicle, or organelle level. Such insight depends on the spatiotemporal resolution and sensitivity of a given microscopy method. Confocal microscopes optically section the cell and improve image contrast and axial resolution (>600 nm) compared with conventional epifluorescence microscopes. Another approach, which can selectively excite fluorophores in an even thinner optical plane (microscopy (TIRFM). The key principle of TIRFM is that a thin, exponentially decaying, evanescent field of excitation can be generated at the interface of two mediums of different refractive index (RI) (e.g., the glass coverslip and the biological specimen); as such, TIRFM is ill-suited to deep imaging of cells or tissue. However, for processes near the lower cell cortex, the sensitivity of TIRFM is exquisite. The recent availability of a very high numerical-aperture (NA) objective lens (>1.45) and turnkey TIRFM systems by all the major microscopy manufacturers has made TIRFM increasingly accessible and attractive to biologists, especially when performed in a quantitative manner and complemented with orthogonal genetic and molecular manipulations. This protocol describes the procedure for alignment and calibration of TIRFM systems using standard cellular samples. The goal is to correctly collimate and align the TIRF illuminator vis-à-vis the downstream optics. For illustration, a 488-nm laser and green fluorescent protein (GFP) filter cube are used.

  2. Microplate-compatible total internal reflection fluorescence microscopy for receptor pharmacology

    Science.gov (United States)

    Chen, Minghan; Zaytseva, Natalya V.; Wu, Qi; Li, Min; Fang, Ye

    2013-05-01

    We report the use of total internal reflection fluorescence (TIRF) microscopy for analyzing receptor pharmacology and the development of a microplate-compatible TIRF imaging system. Using stably expressed green fluorescence protein tagged β2-adrenergic receptor as the reporter, we found that the activation of different receptors results in distinct kinetic signatures of the TIRF intensity of cells. These TIRF signatures closely resemble the characteristics of their respective label-free dynamic mass redistribution signals in the same cells. This suggests that TIRF in microplate can be used for profiling and screening drugs.

  3. Single cell adhesion strength assessed with variable-angle total internal reflection fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Marcelina Cardoso Dos Santos

    2017-06-01

    Full Text Available We propose a new strategy to evaluate adhesion strength at the single cell level. This approach involves variable-angle total internal reflection fluorescence microscopy to monitor in real time the topography of cell membranes, i.e. a map of the membrane/substrate separation distance. According to the Boltzmann distribution, both potential energy profile and dissociation energy related to the interactions between the cell membrane and the substrate were determined from the membrane topography. We have highlighted on glass substrates coated with poly-L-lysine and fibronectin, that the dissociation energy is a reliable parameter to quantify the adhesion strength of MDA-MB-231 motile cells.

  4. Nanograting-based plasmon enhancement for total internal reflection fluorescence microscopy of live cells

    International Nuclear Information System (INIS)

    Kim, Kyujung; Cho, Eun-Jin; Suh, Jin-Suck; Huh, Yong-Min; Kim, Donghyun; Kim, Dong Jun

    2009-01-01

    We investigated evanescent field enhancement based on subwavelength nanogratings for improved sensitivity in total internal reflection microscopy of live cells. The field enhancement is associated with subwavelength-grating-coupled plasmon excitation. An optimum sample employed a silver grating on a silver film and an SF10 glass substrate. Field intensity was enhanced by approximately 90% when measured by fluorescent excitation of microbeads relative to that on a bare prism as a control, which is in good agreement with numerical results. The subwavelength-grating-mediated field enhancement was also applied to live cell imaging of quantum dots, which confirmed the sensitivity enhancement qualitatively.

  5. Label free imaging of cell-substrate contacts by holographic total internal reflection microscopy.

    Science.gov (United States)

    Mandracchia, Biagio; Gennari, Oriella; Marchesano, Valentina; Paturzo, Melania; Ferraro, Pietro

    2017-09-01

    The study of cell adhesion contacts is pivotal to understand cell mechanics and interaction at substrates or chemical and physical stimuli. We designed and built a HoloTIR microscope for label-free quantitative phase imaging of total internal reflection. Here we show for the first time that HoloTIR is a good choice for label-free study of focal contacts and of cell/substrate interaction as its sensitivity is enhanced in comparison with standard TIR microscopy. Finally, the simplicity of implementation and relative low cost, due to the requirement of less optical components, make HoloTIR a reasonable alternative, or even an addition, to TIRF microscopy for mapping cell/substratum topography. As a proof of concept, we studied the formation of focal contacts of fibroblasts on three substrates with different levels of affinity for cell adhesion. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Quantifying the Assembly of Multicomponent Molecular Machines by Single-Molecule Total Internal Reflection Fluorescence Microscopy.

    Science.gov (United States)

    Boehm, E M; Subramanyam, S; Ghoneim, M; Washington, M Todd; Spies, M

    2016-01-01

    Large, dynamic macromolecular complexes play essential roles in many cellular processes. Knowing how the components of these complexes associate with one another and undergo structural rearrangements is critical to understanding how they function. Single-molecule total internal reflection fluorescence (TIRF) microscopy is a powerful approach for addressing these fundamental issues. In this article, we first discuss single-molecule TIRF microscopes and strategies to immobilize and fluorescently label macromolecules. We then review the use of single-molecule TIRF microscopy to study the formation of binary macromolecular complexes using one-color imaging and inhibitors. We conclude with a discussion of the use of TIRF microscopy to examine the formation of higher-order (i.e., ternary) complexes using multicolor setups. The focus throughout this article is on experimental design, controls, data acquisition, and data analysis. We hope that single-molecule TIRF microscopy, which has largely been the province of specialists, will soon become as common in the tool box of biophysicists and biochemists as structural approaches have become today. © 2016 Elsevier Inc. All rights reserved.

  7. Removing the effect of blooming from potential energy measurement by employing total internal reflection microscopy integrated with video microscopy.

    Science.gov (United States)

    Cao, Feng; Gong, Xiangjun; He, Chuanxin; Ngai, To

    2017-10-01

    Total internal reflection microscopy (TIRM) measures the interactions between a colloidal particle and a flat surface in aqueous solution. Recently, TIRM has further integrated with video microscopy (VM) and enabled the simultaneous measurements of multi-particle colloid-surface interactions in the same ensemble. However, there still remain challenges about accurate image acquisition due to blooming. Blooming means the number of photons reaching the detector exceeds its maximum capacity, and the excess photons will either spill to adjacent pixels or not be counted, leading to an obstacle from precise determination of intensity. Our result shows that blooming gives rise to a deviation of the measured potential energy from the classical theory of Derjaguin, Landau, Verway, and Overbeek (DLVO). Therefore, a correction method was developed in this work to deduce the real intensity from the experimental measurement. The relationship between scattered light intensity and exposure time deviates from linearity when blooming occurs. A correction equation was developed to recover the real intensity, which was then confirmed by the accordance between the corresponding potential energy profiles and the DLVO theory. This correction method is suitable for VM systems of colloidal probes illuminated by scattered light, broadening the application of VM imaging to investigate colloidal interactions. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Development of a scanning microscopy by total internal reflection coupled with thermal lens spectroscopy.

    Science.gov (United States)

    Shimosaka, Takuya; Iwamoto, Kazutoshi; Izako, Masakazu; Suzuki, Asa; Uchiyama, Katsumi; Hobo, Toshiyuki

    2004-01-01

    Non-destructive measurement of a small region on a solid/liquid interface is of great importance in physical chemistry and biochemistry, especially in the research of thin films and cell membranes. Optical methods for surface analysis with high lateral resolution are suitable methods for monitoring them. We now report a new scanning optical microscopic method to which total internal reflection coupled with a thermal lens technique was introduced. Its lateral resolution was estimated both experimentally and theoretically. To experimentally estimate the resolution, the grid patterns of thin photoresist films with well-defined lateral structures were measured. The experimental resolution was about 45 microm, which was almost same as the diameter of the excitation beam at a glass/sample interface. From this result, it was verified that this new scanning microscopy ideally worked.

  9. Common-path configuration in total internal reflection digital holography microscopy.

    Science.gov (United States)

    Calabuig, Alejandro; Matrecano, Marcella; Paturzo, Melania; Ferraro, Pietro

    2014-04-15

    Total Internal Reflection Digital Holographic Microscopy (TIRDHM) is recognized to be a powerful tool for retrieving quantitative phase images of cell-substrate interfaces, adhesions, and tissue structures close to the prism surface. In this Letter, we develop an improved TIRDHM system, taking advantage of a refractive index mismatch between the prism and the sample substrate, to allow phase-shifting DH with just a single-beam interferometric configuration. Instead of the traditional off-axis method, phase-shift method is used to retrieve amplitude and phase images in coherent light and TIR modality. Essentially, the substrate-prism interface acts like a beam splitter generating a reference beam, where the phase-shift dependence on the incident angle is exploited in this common-path configuration. With the aim to demonstrate the technique's validity, some experiments are performed to establish the advantage of this compact and simple configuration, in which the reference arm in the setup is avoided.

  10. New light on ion channel imaging by total internal reflection fluorescence (TIRF) microscopy.

    Science.gov (United States)

    Yamamura, Hisao; Suzuki, Yoshiaki; Imaizumi, Yuji

    2015-05-01

    Ion channels play pivotal roles in a wide variety of cellular functions; therefore, their physiological characteristics, pharmacological responses, and molecular structures have been extensively investigated. However, the mobility of an ion channel itself in the cell membrane has not been examined in as much detail. A total internal reflection fluorescence (TIRF) microscope allows fluorophores to be imaged in a restricted region within an evanescent field of less than 200 nm from the interface of the coverslip and plasma membrane in living cells. Thus the TIRF microscope is useful for selectively visualizing the plasmalemmal surface and subplasmalemmal zone. In this review, we focused on a single-molecule analysis of the dynamic movement of ion channels in the plasma membrane using TIRF microscopy. We also described two single-molecule imaging techniques under TIRF microscopy: fluorescence resonance energy transfer (FRET) for the identification of molecules that interact with ion channels, and subunit counting for the determination of subunit stoichiometry in a functional channel. TIRF imaging can also be used to analyze spatiotemporal Ca(2+) events in the subplasmalemma. Single-molecule analyses of ion channels and localized Ca(2+) signals based on TIRF imaging provide beneficial pharmacological and physiological information concerning the functions of ion channels. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  11. Heterogeneous amylin fibril growth mechanisms imaged by total internal reflection fluorescence microscopy.

    Science.gov (United States)

    Patil, Sharadrao M; Mehta, Andrew; Jha, Suman; Alexandrescu, Andrei T

    2011-04-12

    Total internal reflection fluorescence microscopy has been used to visualize the fibrillization of amylin, a hormone which in aggregated forms plays a role in type 2 diabetes pathology. Data were obtained at acidic pH where fibrillization is hindered by the charging of histidine 18 and at slightly basic pH where the loss of charge on the histidine promotes aggregation. The experiments show three types of aggregate growth processes. In the earliest steps globular seeds are formed with some expanding radially during the course of the reaction. The dimensions of the globular seeds as well as their staining with the amyloid-specific dye thioflavin T indicate that they are plaques of short fibrils. The next species observed are fibrils that invariably grow from large globular seeds or smaller punctate granules. Fibril elongation appears to be unidirectional, although in some cases multiple fibrils radiate from a single seed or granule. After fibrils are formed, some show an increase in fluorescence intensity that we attribute to the growth of new fibrils alongside those previously formed. All three aggregation processes are suggestive of secondary (heterogeneous) nucleation mechanisms in which nucleation occurs on preformed fibrils. Consistently, electron micrographs show changes in fibril morphology well after fibrils are first formed, and the growth processes observed by fluorescence microscopy occur after the corresponding solution reactions have reached an initial apparent plateau. Taken together, the results highlight the importance of secondary nucleation in the fibrillization of amylin, as this could provide a pathway to continue fibril growth once an initial population of fibrils is established.

  12. Attenuated total internal reflection infrared microscopy of multilayer plastic packaging foils.

    Science.gov (United States)

    van Dalen, Gerard; Heussen, Patricia C M; den Adel, Ruud; Hoeve, Robert B J

    2007-06-01

    Multilayer plastic foils are important packaging materials that are used to extend the shelf life of food products and drinks. Fourier transform infrared (FT-IR) spectroscopic imaging using attenuated total internal reflection (ATR) can be used for the identification and localization of different layers in multilayer foils. A new type of ATR crystal was used in combination with a linear array detector through which large sample areas (400 x 400 microm(2)) could be imaged with a pixel size of 1.6 microm. The method was tested on laminated plastic packing materials containing 5 to 12 layers. The results of the identification of the different materials using ATR-FT-IR were compared with differential scanning calorimetry (DSC) and the layer thickness of the individual layers measured by ATR-FT-IR was compared with polarized light microscopy (LM) and scanning electron microscopy (SEM). It has been demonstrated that individual layers with a thickness of about 3 microm could be identified in multilayer foils with a total thickness ranging from 100 to 150 microm. The results show a spatial resolution of about 4 microm (measured at wavenumbers ranging from 1000 to 1730 cm(-1)), which is about a factor of two better than can be obtained using transmission FT-IR imaging. An additional advantage of ATR is the ease of sample preparation. A good correspondence was found between visible and FT-IR images. The results of ATR-FT-IR imaging were in agreement with those obtained by LM, SEM, and DSC. ATR-FT-IR is superior to the combination of these techniques because it delivers both spatial and chemical information.

  13. High Refractive Index Silicone Gels for Simultaneous Total Internal Reflection Fluorescence and Traction Force Microscopy of Adherent Cells

    Science.gov (United States)

    Besser, Achim; Sundd, Prithu; Ley, Klaus; Danuser, Gaudenz; Ginsberg, Mark H.; Groisman, Alex

    2011-01-01

    Substrate rigidity profoundly impacts cellular behaviors such as migration, gene expression, and cell fate. Total Internal Reflection Fluorescence (TIRF) microscopy enables selective visualization of the dynamics of substrate adhesions, vesicle trafficking, and biochemical signaling at the cell-substrate interface. Here we apply high-refractive-index silicone gels to perform TIRF microscopy on substrates with a wide range of physiological elastic moduli and simultaneously measure traction forces exerted by cells on the substrate. PMID:21961031

  14. Single-Molecule Fluorescence Studies of Membrane Transporters Using Total Internal Reflection Microscopy.

    Science.gov (United States)

    Goudsmits, Joris M H; van Oijen, Antoine M; Slotboom, Dirk J

    2017-01-01

    Cells are delineated by a lipid bilayer that physically separates the inside from the outer environment. Most polar, charged, or large molecules require proteins to reduce the energetic barrier for passage across the membrane and to achieve transport rates that are relevant for life. Here, we describe techniques to visualize the functioning of membrane transport proteins with fluorescent probes at the single-molecule level. First, we explain how to produce membrane-reconstituted transporters with fluorescent labels. Next, we detail the construction of a microfluidic flow cell to image immobilized proteoliposomes on a total internal reflection fluorescence microscope. We conclude by describing the methods that are needed to analyze fluorescence movies and obtain useful single-molecule data. © 2017 Elsevier Inc. All rights reserved.

  15. Measurements of long-range interactions between protein-functionalized surfaces by total internal reflection microscopy.

    Science.gov (United States)

    Wang, Zhaohui; Gong, Xiangjun; Ngai, To

    2015-03-17

    Understanding the interaction between protein-functionalized surfaces is an important subject in a variety of protein-related processes, ranging from coatings for biomedical implants to targeted drug carriers and biosensors. In this work, utilizing a total internal reflection microscope (TIRM), we have directly measured the interactions between micron-sized particles decorated with three types of common proteins concanavalin A (ConA), bovine serum albumin (BSA), lysozyme (LYZ), and glass surface coated with soy proteins (SP). Our results show that the protein adsorption greatly affects the charge property of the surfaces, and the interactions between those protein-functionalized surfaces depend on solution pH values. At pH 7.5-10.0, all these three protein-functionalized particles are highly negatively charged, and they move freely above the negatively charged SP-functionalized surface. The net interaction between protein-functionalized surfaces captured by TIRM was found as a long-range, nonspecific double-layer repulsion. When pH was decreased to 5.0, both protein-functionalized surfaces became neutral and double-layer repulsion was greatly reduced, resulting in adhesion of all three protein-functionalized particles to the SP-functionalized surface due to the hydrophobic attraction. The situation is very different at pH = 4.0: BSA-decorated particles, which are highly charged, can move freely above the SP-functionalized surfaces, while ConA- and LYZ-decorated particles can only move restrictively in a limited range. Our results quantify these nonspecific kT-scale interactions between protein-functionalized surfaces, which will enable the design of surfaces for use in biomedical applications and study of biomolecular interactions.

  16. Enhanced detection sensitivity of carcinoembryonic antigen on a plasmonic nanoimmunosensor by transmission grating-based total internal reflection scattering microscopy.

    Science.gov (United States)

    Ahn, Sujin; Yu, Hyunung; Kang, Seong Ho

    2017-10-15

    Carcinoembryonic antigen (CEA) is a glycoprotein associated with colorectal carcinomas and is commonly used as a clinical tumor marker. Enhanced detection sensitivity for the assay of CEA molecules was achieved on a plasmonic nanoimmunosensor by wavelength-dependent transmission grating (TG)-based total internal reflection scattering microscopy (TIRSM). The plasmonic nanoparticles were placed in an evanescent field layer on a glass nanoimmunosensor that produced evanescent wave scattering by the total internal reflection of light from two lasers. The light scattered by target protein (CEA)-bound 20-nm silver nanoparticles (plasmonic nanoprobes) was collected and spectrally isolated in first-order spectral images (n=+1) by a TG (70 grooves/mm). The combination of evanescent wave scattering and TG ​significantly enhanced the detection sensitivity and selectivity due to the minimized spectroscopic interference and background noise. The TG-TIRSM method detected the CEA molecules at concentrations down to 19.75zM with a wide linear dynamic range of 19.75zM-39.50nM (correlation coefficient, R=0.9903), which was 45 to 1.25×10 9 times lower than the detection limits and 2×10 5 to 2×10 11 times wider than the dynamic ranges of previous assay methods. In particular, by simply changing the antibody of the target molecule, this technique can be used to detect various disease-related protein biomarkers directly in human biological samples at the single-molecule level. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Direct visualization of the reaction transformation and signal amplification in a DNA molecular machine with total internal reflection fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Rui eRen

    2013-10-01

    Full Text Available In this study, as a proof of concept, the signal amplification in an artificial DNA molecular machine was directly visualized via total internal reflection fluorescence microscopy (TIRFM. The molecular machine brought about obvious morphology change in DNA nanostructures as well as signal amplifications. On one hand, through a triggered and autonomically repeated RCA, a DNA nano-complex featuring a locked circular DNA template (serving as raw feed was converted into a long periodically repeated strand, i.e. the RCA products. Furthermore, this RCA was repeated in three controllable reaction phases, bring about progressive signal amplification. It was testified that the RCA products (presented as long thread-like fluorescent objects can be easily distinguished from the inputted DNA probes (presented as fluorescent dots, thus the transformation in reaction can be visualized. Also, by quantitive counting of the aforementioned fluorescence objects, the progress of the reaction through the phases, along with time, and over the lysozyme concentration can be demonstrated through TIRFM visualization. Overall, it was demonstrated that TIRFM is an efficient approach to quantitively visualize the biochemical processes at single-molecule level.

  18. International Multidisciplinary Microscopy Congress

    CERN Document Server

    Oral, Ahmet; Ozer, Mehmet; InterM; INTERM2013

    2014-01-01

    The International Multidisciplinary Microscopy Congress (INTERM2013) was organized on October 10-13, 2013. The aim of the congress was to bring together scientists from various branches to discuss the latest advances in the field of microscopy. The contents of the congress have been broadened to a more "interdisciplinary" scope, so as to allow all scientists working on related subjects to participate and present their work. These proceedings include 39 peer-reviewed technical papers, submitted by leading academic and research institutions from over 12 countries and representing some of the most cutting-edge research available. The 39 papers are grouped into the following sections: - Applications of Microscopy in the Physical Sciences - Applications of Microscopy in the Biological Sciences

  19. Total internal reflection fluorescence (TIRF) microscopy for real-time imaging of nanoparticle-cell plasma membrane interaction

    DEFF Research Database (Denmark)

    Parhamifar, Ladan; Moghimi, Seyed Moien

    2012-01-01

    fluorescence (TIRF) microscopy allows for real-time monitoring of nanoparticle-membrane interaction events, which can provide vital information in relation to design and surface engineering of therapeutic nanoparticles for cell-specific targeting. In contrast to other microscopy techniques, the bleaching...... effect by lasers in TIRF microscopy is considerably less when using fluorescent nanoparticles and it reduces photo-induced cytotoxicity during visualization of live-cell events since it only illuminates the specific area near or at the plasma membrane....

  20. Auto-calibrated scanning-angle prism-type total internal reflection microscopy for nanometer-precision axial position determination and optional variable-illumination-depth pseudo total internal reflection microscopy

    Science.gov (United States)

    Fang, Ning; Sun, Wei

    2015-04-21

    A method, apparatus, and system for improved VA-TIRFM microscopy. The method comprises automatically controlled calibration of one or more laser sources by precise control of presentation of each laser relative a sample for small incremental changes of incident angle over a range of critical TIR angles. The calibration then allows precise scanning of the sample for any of those calibrated angles for higher and more accurate resolution, and better reconstruction of the scans for super resolution reconstruction of the sample. Optionally the system can be controlled for incident angles of the excitation laser at sub-critical angles for pseudo TIRFM. Optionally both above-critical angle and sub critical angle measurements can be accomplished with the same system.

  1. Imaging exocytosis of single glucagon-like peptide-1 containing granules in a murine enteroendocrine cell line with total internal reflection fluorescent microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ohara-Imaizumi, Mica; Aoyagi, Kyota [Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Akimoto, Yoshihiro [Department of Anatomy, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Nakamichi, Yoko; Nishiwaki, Chiyono [Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Kawakami, Hayato [Department of Anatomy, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan); Nagamatsu, Shinya, E-mail: shinya@ks.kyorin-u.ac.jp [Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611 (Japan)

    2009-12-04

    To analyze the exocytosis of glucagon-like peptide-1 (GLP-1) granules, we imaged the motion of GLP-1 granules labeled with enhanced yellow fluorescent protein (Venus) fused to human growth hormone (hGH-Venus) in an enteroendocrine cell line, STC-1 cells, by total internal reflection fluorescent (TIRF) microscopy. We found glucose stimulation caused biphasic GLP-1 granule exocytosis: during the first phase, fusion events occurred from two types of granules (previously docked granules and newcomers), and thereafter continuous fusion was observed mostly from newcomers during the second phase. Closely similar to the insulin granule fusion from pancreatic {beta} cells, the regulated biphasic exocytosis from two types of granules may be a common mechanism in glucose-evoked hormone release from endocrine cells.

  2. Total internal reflection fluorescence anisotropy imaging microscopy: setup, calibration, and data processing for protein polymerization measurements in living cells

    Science.gov (United States)

    Ströhl, Florian; Wong, Hovy H. W.; Holt, Christine E.; Kaminski, Clemens F.

    2018-01-01

    Fluorescence anisotropy imaging microscopy (FAIM) measures the depolarization properties of fluorophores to deduce molecular changes in their environment. For successful FAIM, several design principles have to be considered and a thorough system-specific calibration protocol is paramount. One important calibration parameter is the G factor, which describes the system-induced errors for different polarization states of light. The determination and calibration of the G factor is discussed in detail in this article. We present a novel measurement strategy, which is particularly suitable for FAIM with high numerical aperture objectives operating in TIRF illumination mode. The method makes use of evanescent fields that excite the sample with a polarization direction perpendicular to the image plane. Furthermore, we have developed an ImageJ/Fiji plugin, AniCalc, for FAIM data processing. We demonstrate the capabilities of our TIRF-FAIM system by measuring β -actin polymerization in human embryonic kidney cells and in retinal neurons.

  3. Three-dimensional particle tracking in concave structures made by ultraviolet nanoimprint via total internal reflection fluorescence microscopy and refractive-index-matching method

    Science.gov (United States)

    Fujinami, Taku; Kigami, Hiroshi; Unno, Noriyuki; Taniguchi, Jun; Satake, Shin-ichi

    2018-03-01

    Total internal reflection fluorescence microscopy (TIRFM) is a promising method for measuring fluid flow close to a wall with nanoscale resolution in a process that is termed "multilayer nanoparticle image velocimetry" (MnPIV). TIRFM uses evanescent light that is generated on a substrate (typically a glass slide) by total internal reflection of light. Many researchers have previously studied x-y-z (3D) flows of water close to flat glass slides using MnPIV. On the other hand, a fluid flow close to a structured surface is also important. To measure flows of water near micro-patterns, we previously developed an MnPIV technique that uses a refractive-index-matching method. In previous study, the micropattern is made of a thermoplastic material with a refractive index that closely matches that of water. In this study, ultraviolet nanoimprint lithography was used for fabricating the appropriate micro-patterns because this technique can fabricate a pattern with a high resolution. As a result, we succeeded in performing MnPIV in water with a circular hole array pattern made by ultraviolet nanoimprint using a refractive-index-matching method. We believe that this technique will be helpful in elucidating fluid flows around microstructures.

  4. Reflectance Confocal Microscopy in Lentigo Maligna.

    Science.gov (United States)

    Gamo, R; Pampín, A; Floristán, U

    2016-12-01

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

  5. In vivo intraoral reflectance confocal microscopy of an amalgam tattoo

    OpenAIRE

    Yélamos, Oriol; Cordova, Miguel; Peterson, Gary; Pulitzer, Melissa P.; Singh, Bhuvanesh; Rajadhyaksha, Milind; DeFazio, Jennifer L.

    2017-01-01

    The majority of oral pigmentations are benign lesions such as nevi, melanotic macules, melanoacanthomas or amalgam tattoos. Conversely, mucosal melanomas are rare but often lethal; therefore, excluding oral melanomas in this setting is crucial. Reflectance confocal microscopy is a non-invasive, in vivo imaging system with cellular resolution that has been used to distinguish benign from malignant pigmented lesions in the skin, and more recently in the mucosa. However, lesions located posterio...

  6. Automated identification of epidermal keratinocytes in reflectance confocal microscopy

    Science.gov (United States)

    Gareau, Dan

    2011-03-01

    Keratinocytes in skin epidermis, which have bright cytoplasmic contrast and dark nuclear contrast in reflectance confocal microscopy (RCM), were modeled with a simple error function reflectance profile: erf( ). Forty-two example keratinocytes were identified as a training set which characterized the nuclear size a = 8.6+/-2.8 μm and reflectance gradient b = 3.6+/-2.1 μm at the nuclear/cytoplasmic boundary. These mean a and b parameters were used to create a rotationally symmetric erf( ) mask that approximated the mean keratinocyte image. A computer vision algorithm used an erf( ) mask to scan RCM images, identifying the coordinates of keratinocytes. Applying the mask to the confocal data identified the positions of keratinocytes in the epidermis. This simple model may be used to noninvasively evaluate keratinocyte populations as a quantitative morphometric diagnostic in skin cancer detection and evaluation of dermatological cosmetics.

  7. Reflections on international medical law.

    Science.gov (United States)

    Wattad, Mohammed S; Hrevtsova, Radmyla Yu

    2011-12-01

    Does international medical law exist, in the first place, as an independent area of study? If so, is it urgently required in an era of comparative studies? Namely, to what extent, if at all, international studies differ from comparative ones? Besides, what are the particular characteristics of such international discipline? Namely, what are the particular features of this field that elaborate on our legal and scientific understanding in sketching possible definition for this notion of "international medical law?" In addition, how does international medical law correlate with health, ethics and health policies in our globalized world? And finally, what are the challenges that might face the international community, once the concept of "international medical law" is acknowledged? This papers aims at establishing the conceptual grounds for these questions, thus calling for the acknowledgment of a new field of study described as "international medical law".

  8. Studies of the Reflection, Refraction and Internal Reflection of Light

    Science.gov (United States)

    Lanchester, P. C.

    2014-01-01

    An inexpensive apparatus and associated experiments are described for studying the basic laws of reflection and refraction of light at an air-glass interface, and multiple internal reflections within a glass block. In order to motivate students and encourage their active participation, a novel technique is described for determining the refractive…

  9. Total internal reflection effect on gyrotropic interface

    Science.gov (United States)

    Glushchenko, Alexander G.; Glushchenko, Eugene P.; Zhukov, Sergey V.

    2018-02-01

    This article considers the physical features of total internal reflection at gyrotropic and isotropic interfaces for two cases: electrical gyrotropy (plasma) and magnetic gyrotropy (ferrite). It is shown that the plasma magnetization may lead to the formation of the total internal reflection effect, which does not occur in isotropic plasma. The threshold values of the magnetic field, which are necessary for the total internal reflection effect, are determined. The total internal reflection effect on a ferrite-dielectric interface for waves emanating from different angles is observed in various frequency ranges and magnetization fields. The study points out the possibility of changing the total internal reflection angle value in large limits due to a change in the external magnetic field magnitude. The calculation results of the total internal reflection angle dependence on the external magnetic field magnitude are presented. The formulas are elaborated for calculating the total internal reflection angles of different interfaces for gyrotropic and isotropic media. The generalized formulas are defined for calculating the Doppler effect in the gyrotropic media. The study demonstrates how the velocity of the media interface affects the limiting angle of total internal refection.

  10. In vivo intraoral reflectance confocal microscopy of an amalgam tattoo.

    Science.gov (United States)

    Yélamos, Oriol; Cordova, Miguel; Peterson, Gary; Pulitzer, Melissa P; Singh, Bhuvanesh; Rajadhyaksha, Milind; DeFazio, Jennifer L

    2017-10-01

    The majority of oral pigmentations are benign lesions such as nevi, melanotic macules, melanoacanthomas or amalgam tattoos. Conversely, mucosal melanomas are rare but often lethal; therefore, excluding oral melanomas in this setting is crucial. Reflectance confocal microscopy is a non-invasive, in vivo imaging system with cellular resolution that has been used to distinguish benign from malignant pigmented lesions in the skin, and more recently in the mucosa. However, lesions located posteriorly in the oral cavity are difficult to assess visually and difficult to biopsy due to their location. Herein we present a patient with previous multiple melanomas presenting with an oral amalgam tattoo in the buccal mucosa, which was imaged using an intraoral telescopic probe attached to a commercially available handheld RCM. In this case report we describe this novel probe, the first RCM description of an amalgam tattoo and we discuss its differences with the findings described in oral melanomas.

  11. Image segmentation for integrated multiphoton microscopy and reflectance confocal microscopy imaging of human skin in vivo.

    Science.gov (United States)

    Chen, Guannan; Lui, Harvey; Zeng, Haishan

    2015-02-01

    Non-invasive cellular imaging of the skin in vivo can be achieved in reflectance confocal microscopy (RCM) and multiphoton microscopy (MPM) modalities to yield complementary images of the skin based on different optical properties. One of the challenges of in vivo microscopy is the delineation (i.e., segmentation) of cellular and subcellular architectural features. In this work we present a method for combining watershed and level-set models for segmentation of multimodality images obtained by an integrated MPM and RCM imaging system from human skin in vivo. Firstly, a segmentation model based on watershed is introduced for obtaining the accurate structure of cell borders from the RCM image. Secondly,, a global region based energy level-set model is constructed for extracting the nucleus of each cell from the MPM image. Thirdly, a local region-based Lagrange Continuous level-set approach is used for segmenting cytoplasm from the MPM image. Experimental results demonstrated that cell borders from RCM image and boundaries of cytoplasm and nucleus from MPM image can be obtained by our segmentation method with better accuracy and effectiveness. We are planning to use this method to perform quantitative analysis of MPM and RCM images of in vivo human skin to study the variations of cellular parameters such as cell size, nucleus size and other mophormetric features with skin pathologies.

  12. Live cell refractometry using Hilbert phase microscopy and confocal reflectance microscopy.

    Science.gov (United States)

    Lue, Niyom; Choi, Wonshik; Popescu, Gabriel; Yaqoob, Zahid; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S

    2009-11-26

    Quantitative chemical analysis has served as a useful tool for understanding cellular metabolisms in biology. Among many physical properties used in chemical analysis, refractive index in particular has provided molecular concentration that is an important indicator for biological activities. In this report, we present a method of extracting full-field refractive index maps of live cells in their native states. We first record full-field optical thickness maps of living cells by Hilbert phase microscopy and then acquire physical thickness maps of the same cells using a custom-built confocal reflectance microscope. Full-field and axially averaged refractive index maps are acquired from the ratio of optical thickness to physical thickness. The accuracy of the axially averaged index measurement is 0.002. This approach can provide novel biological assays of label-free living cells in situ.

  13. Detection of desmoplastic melanoma with dermoscopy and reflectance confocal microscopy.

    Science.gov (United States)

    Maher, N G; Solinas, A; Scolyer, R A; Puig, S; Pellacani, G; Guitera, P

    2017-12-01

    Desmoplastic melanoma (DM) is frequently misdiagnosed clinically and often associated with melanoma in situ (MIS). To improve the detection of DM using dermoscopy and reflectance confocal microscopy (RCM). A descriptive analysis of DM dermoscopy features and a case-control study within a melanoma population for RCM feature evaluation was performed blindly, using data obtained between 2005 and 2015. After retrospectively identifying all DM cases with RCM data over the study period (n = 16), a control group of non-DM melanoma patients with RCM data, in a ratio of at least 3 : 1, was selected. The control group was matched by age and primary tumour site location, divided into non-DM invasive melanomas (n = 27) and MIS (n = 27). Invasive melanomas were selected according to the melanoma subtypes associated with the DM cases. The main outcomes were the frequency of melanoma-specific features on dermoscopy for DM; and the odds ratios of RCM features to distinguish DM from MIS and/or other invasive melanomas; or MIS from the combined invasive melanoma group. At least one of the 14 melanoma-specific features evaluated on dermoscopy was found in 100% of DMs (n = 15 DM with dermoscopy). Known RCM melanoma predictors were commonly found in the DMs, such as pagetoid cells (100%) and cell atypia (100%). The RCM feature of spindle cells in the superficial dermis was more common in DM compared with the entire melanoma control group (OR 3.82, 95% CI 1.01-14.90), and particularly compared to MIS (OR 5.48, 95% CI 1.11-32.36). Nucleated cells in the dermis and the RCM correlate of dermal inflammation were also significant RCM features favouring DM over MIS, as well as invasive melanoma over MIS. Dermoscopy and RCM may be useful tools for the identification of DM. Certain RCM features may help distinguish DM from MIS and other invasive melanomas. Larger studies are warranted. © 2017 European Academy of Dermatology and Venereology.

  14. 3rd International Multidisciplinary Microscopy and Microanalysis Congress

    CERN Document Server

    Oral, Zehra

    2017-01-01

    The 3rd International Multidisciplinary Microscopy Congress (InterM2015), held from 19 to 23 October 2015, focused on the latest developments concerning applications of microscopy in the biological, physical and chemical sciences at all dimensional scales, advances in instrumentation, techniques in and educational materials on microscopy. These proceedings gather 17 peer-reviewed technical papers submitted by leading academic and research institutions from nine countries and representing some of the most cutting-edge research available.

  15. Total Internal Reflection Fluorescence Quantification of Receptor Pharmacology

    Directory of Open Access Journals (Sweden)

    Ye Fang

    2015-04-01

    Full Text Available Total internal reflection fluorescence (TIRF microscopy has been widely used as a single molecule imaging technique to study various fundamental aspects of cell biology, owing to its ability to selectively excite a very thin fluorescent volume immediately above the substrate on which the cells are grown. However, TIRF microscopy has found little use in high content screening due to its complexity in instrumental setup and experimental procedures. Inspired by the recent demonstration of label-free evanescent wave biosensors for cell phenotypic profiling and drug screening with high throughput, we had hypothesized and demonstrated that TIRF imaging is also amenable to receptor pharmacology profiling. This paper reviews key considerations and recent applications of TIRF imaging for pharmacology profiling.

  16. Total internal reflection tomography of small objects

    International Nuclear Information System (INIS)

    Chen Xudong

    2008-01-01

    The multiple signal classification (MUSIC) imaging method is applied to determine the locations of a collection of small anisotropic spherical scatterers in the framework of the total internal reflection tomography. Multiple scattering between scatterers is considered and the inverse scattering problem is nonlinear, which, however, is solved by the proposed fast analytical approach where no associated forward problem is iteratively evaluated. The paper also discusses the role of the polarization of incidence waves, the incidence angle, the separation of scatterers from the surface of the substrate, and the level of noise on the resolution of imaging.

  17. Spectral confocal reflection microscopy using a white light source

    Science.gov (United States)

    Booth, M.; Juškaitis, R.; Wilson, T.

    2008-08-01

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

  18. Nevomelanocytic atypia detection by in vivo reflectance confocal microscopy

    Directory of Open Access Journals (Sweden)

    Ingrida Vaišnorienė

    2014-01-01

    Conclusions: Nevus with histopathologically confirmed nevomelanocytic atypia (dysplastic nevus could not be distinguished from nevus without atypia using analyzed in vivo RCM features of melanocytic atypia. More accurate diagnostics by means of in vivo RCM needs further investigation on reflectance of single and nested cutaneous melanocytes in benign and malignant skin lesions.

  19. 2nd International Multidisciplinary Microscopy and Microanalysis Congress

    CERN Document Server

    Oral, Ahmet; Ozer, Mehmet

    2015-01-01

    The 2nd International Multidisciplinary Microscopy and Microanalysis Congress & Exhibition (InterM 2014) was held on 16–19 October 2014 in Oludeniz, Fethiye/ Mugla, Turkey. The aim of the congress was to gather scientists from various branches and discuss the latest improvements in the field of microscopy. The focus of the congress has been widened in an "interdisciplinary" manner, so as to allow all scientists working on several related subjects to participate and present their work. These proceedings include 33 peer-reviewed technical papers, submitted by leading academic and research institutions from over 17 countries and representing some of the most cutting-edge research available. The papers were presented at the congress in the following sessions: ·         Applications of Microscopy in the Physical Sciences ·         Applications of Microscopy in the Biological Sciences.

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

    NARCIS (Netherlands)

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

    2012-01-01

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

  1. Total Internal Reflections - Dr. Kapolka Explains Frustrated Total Internal Reflection [video

    OpenAIRE

    Naval Postgraduate School Physics

    2015-01-01

    NPS Physics In-class Physics Demonstrations This is a demo about frustrated total internal reflection. This is a general phenomenon that applies to any kind of wave phenomenon including quantum mechanical waves. Dr. Kapolka is physics professor at the Naval Postgraduate school.

  2. Dielectric and fluorescent samples imaged by scanning near-field optical microscopy in reflection

    OpenAIRE

    Jalocha, A.; Jalocha, A.; van Hulst, N.F.

    1995-01-01

    Dielectric fluorescent samples are imaged by scanning near- field optical microscopy in reflection. A non-metallized tapered fibre tip is used both as an emitter and a detector. Shear force feedback controls the distance between the tip and the sample and gives simultaneously a topographic image of the surface. A direct correlation with the optical image is obtained. We demonstrate that this reflection setup is suitable for dielectric samples. Images in fluorescence have been obtained o­n Lan...

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

    NARCIS (Netherlands)

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

    2011-01-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

  5. Dielectric and fluorescent samples imaged by scanning near-field optical microscopy in reflection

    NARCIS (Netherlands)

    Jalocha, A.; Jalocha, A.; van Hulst, N.F.

    1995-01-01

    Dielectric fluorescent samples are imaged by scanning near- field optical microscopy in reflection. A non-metallized tapered fibre tip is used both as an emitter and a detector. Shear force feedback controls the distance between the tip and the sample and gives simultaneously a topographic image of

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

    Science.gov (United States)

    Yang, Yong-fa; Li, Qi

    2014-12-01

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

  7. Forensic applications of microscopical infrared internal reflection spectroscopy

    Science.gov (United States)

    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.

  8. Cellular resolution expression profiling using confocal detection of NBT/BCIP precipitate by reflection microscopy.

    Science.gov (United States)

    Jékely, Gáspár; Arendt, Detlev

    2007-06-01

    The determination of gene expression patterns in three dimensions with cellular resolution is an important goal in developmental biology. However the most sensitive, efficient, and widely used staining technique for whole-mount in situ hybridization (WMISH), nitroblue tetrazolium (NBT)/5-bromo-4-chloro-3-indolyl phosphate (BCIP) precipitation by alkaline phosphatase, could not yet be combined with the most precise, high-resolution detection technique, confocal laser-scanning microscopy (CLSM). Here we report the efficient visualization of the NBT/BCIP precipitate using confocal reflection microscopy for WMISH samples of Drosophila, zebrafish, and the marine annelid worm, Platynereis dumerilii. In our simple WMISH protocol for reflection CLSM, NBT/BCIP staining can be combined with fluorescent WMISH, immunostainings, or transgenic green fluorescent protein (GFP) marker lines, allowing double labeling of cell types or of embryological structures of interest. Whole-mount reflection CLSM will thus greatly facilitate large-scale cellular resolution expression profiling in vertebrate and invertebrate model organisms.

  9. Structure of ordered polyelectrolyte films from atomic-force microscopy and X-ray reflectivity data

    International Nuclear Information System (INIS)

    Belyaev, V.V.; Tolstikhina, A.L.; Stepina, N.D.; Kayushina, R.L.

    1998-01-01

    The possible application of atomic-force microscopy and X-ray reflectometry methods to structural studies of polyelectrolyte films obtained due to alternating adsorption of oppositely charged polyanion [sodium polysterenesulfonate (PSS)] and polycation [poly(allylamine) hydrochloride (PAA)] layers on solid substrates has been considered. The atomic-force microscopy study has revealed the characteristic features of the surface topography of samples consisting of different numbers of polyelectrolyte layers deposited from solutions characterized by different ionic strength values. It is shown that the shape of the reflectivity curves obtained from thin polyelectrolyte films depends on their surface structure

  10. Reflections on Dead Theory in International Relations

    Science.gov (United States)

    Thakur, Vineet

    2016-01-01

    In this short autobiographical essay, I trace my journey in the discipline of International Relations. While entering the discipline, I, along with a host of my classmates, were enamoured by the exciting possibilities of thinking theoretically. Almost a decade later, those promises look bleak. From the perspective of a student in the discipline, I…

  11. Light Microscopy Module: International Space Station Premier Automated Microscope

    Science.gov (United States)

    Sicker, Ronald J.; Foster, William M.; Motil, Brian J.; Meyer, William V.; Chiaramonte, Francis P.; Abbott-Hearn, Amber; Atherton, Arthur; Beltram, Alexander; Bodzioney, Christopher; Brinkman, John; hide

    2016-01-01

    The Light Microscopy Module (LMM) was launched to the International Space Station (ISS) in 2009 and began hardware operations in 2010. It continues to support Physical and Biological scientific research on ISS. During 2016, if all goes as planned, three experiments will be completed: [1] Advanced Colloids Experiments with Heated base-2 (ACE-H2) and [2] Advanced Colloids Experiments with Temperature control (ACE-T1). Preliminary results, along with an overview of present and future LMM capabilities will be presented; this includes details on the planned data imaging processing and storage system, along with the confocal upgrade to the core microscope. [1] a consortium of universities from the State of Kentucky working through the Experimental Program to Stimulate Competitive Research (EPSCoR): Stuart Williams, Gerold Willing, Hemali Rathnayake, et al. and [2] from Chungnam National University, Daejeon, S. Korea: Chang-Soo Lee, et al.

  12. Similar but Different: How Reflectance Confocal Microscopy May Help in the Diagnosis of Pink Lesions.

    Science.gov (United States)

    Ferrari, Federica; Bassoli, Sara; Pellacani, Giovanni; Argenziano, Giuseppe; Cesinaro, Anna Maria; Longo, Caterina

    2017-01-01

    Among skin neoplasms, solitary pink tumors represent challenging lesions in clinical practice since they can mimic melanocytic and nonmelanocytic lesions or even inflammatory ones. In this case series we described dermoscopic and confocal features of 2 couples of similar lesions in order to achieve the correct diagnosis and the best therapeutic approach. During clinical routine practice, 2 couples of clinically and dermoscopically similar lesions were examined by means of confocal microscopy. All lesions revealed no clear-cut diagnostic features on dermoscopy. However, confocal microscopy revealed tumor islands with palisading cells and a dark clefting at the periphery in basal cell carcinomas. In the other "false twin" lesions, atypical cells and elongated junctional nests were observed and the diagnosis of amelanotic melanomas was rendered. In the current case series, the combined use of dermoscopy and reflectance confocal microscopy was an optimal workup for difficult-to-diagnose lesions such as pink tumors. © 2017 S. Karger AG, Basel.

  13. Reflections about therapeutic internments and his specificity

    Directory of Open Access Journals (Sweden)

    Ángel Estalayo Hernández

    2014-10-01

    Full Text Available There are cases treated in detention centers that present some specificities with respect to other affordable educational strategies from social component. This we refer to the need to address situations in which the same symptom of transgression resulting in an offense that carries a legal measure has other bases that generate and / or maintain, or etiology marking its expression and so much attention. The approach to interventions with children and young people is a seriously disruptive content submitted to numerous debates, discussions and disagreements. In this regard, therapeutic placements would be for those cases in which the intervention on symptom requires a specific and specialized perspective. Beyond clinical approaches, therapeutic placements should from the intervention on self-regulation problems (emotional, behavioral, and cognitive and behavioral expression and as a key defining element. To this we add that we have observed in our practice in recent years an increase in problems related to the field of mental health and / or drug and alcohol consumption on children and young people entering the judicial context. This requires expertise and implement a therapeutic approach in centers for juvenile justice. It is particularly important in these cases performed from the beginning of internment clinical and social diagnostics to guide and design the specific educational and therapeutic intervention required for each particular case, in the interest of optimizing the operation and achieve higher levels of efficiency

  14. Use of a white light supercontinuum laser for confocal interference-reflection microscopy.

    Science.gov (United States)

    Chiu, L-D; Su, L; Reichelt, S; Amos, W B

    2012-05-01

    Shortly after its development, the white light supercontinuum laser was applied to confocal scanning microscopy as a more versatile substitute for the multiple monochromatic lasers normally used for the excitation of fluorescence. This light source is now available coupled to commercial confocal fluorescence microscopes. We have evaluated a supercontinuum laser as a source for a different purpose: confocal interferometric imaging of living cells and artificial models by interference reflection. We used light in the range 460-700 nm where this source provides a reasonably flat spectrum, and obtained images free from fringe artefacts caused by the longer coherence length of conventional lasers. We have also obtained images of cytoskeletal detail that is difficult to see with a monochromatic laser. © 2012 The Authors Journal of Microscopy © 2012 Royal Microscopical Society.

  15. A morphological study of the sulfurisation of digenite to covellite using reflected polarised light microscopy

    DEFF Research Database (Denmark)

    Rask Møller Frøkiær, Heidi; Warner, Terence E.

    2017-01-01

    A series of copper rods were reacted with sulfur vapour in evacuated glass ampoules at ∼445 °C. Product materials were characterised by powder X-ray diffraction and reflected polarised light microscopy. Copper sulfurised rapidly to digenite, γ-Cu2-xS, under these conditions, whereas the subsequent...... − besides being a p-type metal − is ionically conducting at 445 °C, although considerably less so than digenite. We infer that the growth of platy covellite crystals and their radial alignment in the primary CuS layer are a consequence of copper ion mobility being restricted to the basal plane...

  16. PREFACE: 9th International Conference on X-Ray Microscopy

    Science.gov (United States)

    Quitmann, Christoph; David, Christian; Nolting, Frithjof; Pfeiffer, Franz; Stampanoni, Marco

    2009-09-01

    Conference logo This volume compiles the contributions to the International Conference on X-Ray Microscopy (XRM2008) held on 20-25 July 2008 in Zurich, Switzerland. The conference was the ninth in a series which started in Göttingen in 1984. Over the years the XRM conference series has served as a forum bringing together all relevant players working on the development of methods, building instrumentation, and applying x-ray microscopy to challenging issues in materials science, condensed matter research, environmental science and biology. XRM2008 was attended by about 300 participants who followed 44 oral presentations and presented 220 posters. Conference photograph Figure 1: Participants of the XRM2008 conference gathered in front of the main building of the ETH-Zurich. The conference showed that x-ray microscopy has become a mature field resting on three pillars. The first are workhorse instruments available even to non-specialist users. These exist at synchrotron sources world-wide as well as in laboratories. They allow the application of established microscopy methods to solve scientific projects in areas as diverse as soil science, the investigation of cometary dust particles, magnetic materials, and the analysis of ancient parchments. Examples of all of these projects can be found in this volume. These instruments have become so well understood that now they are also commercially available. The second pillar is the continued development of methods. Methods like stroboscopic imaging, wet cells or high and low temperature environments add versatility to the experiments. Methods like phase retrieval and ptychographic imaging allow the retrieval of information which hitero was thought to be inaccessible. The third pillar is the extension of such instruments and methods to new photon sources. With x-ray free electron lasers on the horizon the XRM community is working to transfer their know-how to these novel sources which will offer unprecedented brightness and

  17. Monitoring treatment response in psoriasis: current perspectives on the clinical utility of reflectance confocal microscopy

    Directory of Open Access Journals (Sweden)

    Agozzino M

    2017-02-01

    Full Text Available Marina Agozzino,1 Cecilia Noal,2 Francesco Lacarrubba,3 Marco Ardigò4 1Dermatology Unit, Second University of Naples, Naples, 2Dermatology Unit, University of Trieste, Trieste, 3Dermatology Clinic, University of Catania, Catania, 4Clinical Dermatology Department, San Gallicano Dermatological Institute, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy Abstract: Reflectance confocal microscopy (RCM evaluation of inflammatory skin diseases represents a relatively new technique that, during the past 5 years, has attracted increasing interest, with consequent progressive increment of publications in literature. The success of RCM is directly related to the high need for noninvasive techniques able to both reduce the number of skin biopsies and support clinical diagnosis and patient management. RCM helps to visualize microscopic descriptors of plaque psoriasis (PP with good reproducibility between observers and a high grade of correspondence with histopathology. Several clinical tests are used for the therapeutic management of PP, but they are limited by subjective interpretation. Skin biopsy presents objective interpretation, but the procedure is invasive and not repeatable. RCM has been used not only for the evaluation of skin cancer or inflammatory skin diseases, but also for monitoring the efficacy of different treatments in PP. In this review, we present some examples of RCM applications in therapeutic psoriasis follow-up. Keywords: reflectance confocal microscopy, psoriasis noninvasive follow-up, psoriasis monitoring

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

    Science.gov (United States)

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

    2017-04-01

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

  19. Maintaining International Peace and Security: Reflections on Peace ...

    African Journals Online (AJOL)

    Maintaining International Peace and Security: Reflections on Peace-Support Operations in Africa. DR THEO NEETHLING. Centrefor Military Studies, University of Stellenbosch. ABSTRACT. The shift from a bipolar to a multipolar and multi-faceted world has reduced the risk of conventional inter-state wars, but has been the ...

  20. Revisit: A Surprising Demonstration of Total Internal Reflection

    Science.gov (United States)

    Lee, Jiwon; Cha, Yu Wha; Jung, Yeon Su; Oh, Eun Ju; Moon, Ye Lin; Kim, Jung Bog

    2016-01-01

    Melton demonstrated a surprising disappearance using total internal reflection. When he put a Florence flask filled with marbles into a water tank and looked straight down from directly above the flask, he was only able to see marbles above a certain water level. When he added more water into the tank above the top line of the marbles, all of the…

  1. Gaining Insight into Antibubbles via Frustrated Total Internal Reflection

    Science.gov (United States)

    Suhr, Wilfried

    2012-01-01

    The interest in the phenomenon of frustrated total internal reflection dates back to the time of Newton. Because of its technological relevance, it has become a standard topic covered by advanced courses in physics. In practical courses optical setups especially designed to demonstrate the phenomenon are commonly used. As an alternative, this…

  2. Double conoscopic figures in total-internal-reflection prisms

    Science.gov (United States)

    Litvinova, M. N.; Stroganov, V. I.; Krishtop, V. V.; Alekseeva, L. V.; Pas'ko, P. G.

    2006-01-01

    This paper presents the results of a study of the features of the formation of double conoscopic figures in total-internal-reflection prisms. The conditions for the existence of double conoscopic figures in the absence of a polarizer and analyzer are explained. An experiment has been done with prisms fabricated from crystals of calcite, potassium dihydrogen phosphate (KDP) and lithium niobate.

  3. International Student Teaching: Stimulus for Developing Reflective Teachers.

    Science.gov (United States)

    Vall, Nancy Gerdin, Tennison, Jo M.

    1992-01-01

    Discusses how culture shock intrinsic in a cross-cultural student teaching experience necessitates that participants think critically and reflect about teaching. The article describes an international student teaching component at two Minnesota colleges. After 7 weeks of student teaching in the United States, participants spend 6 weeks in British…

  4. Microscopy

    Science.gov (United States)

    Patricia A. Moss; Les Groom

    2001-01-01

    Microscopy is the study and interpretation of images produced by a microscope. "Interpretation" is the keyword, because the microscope enables one to see structures that are too small or too close together to be resolved by the unaided eye. (The human eye cannot separate two points or lines that are closer together than 0.1 mm.) it is important to...

  5. Live Cell Refractometry Using Hilbert Phase Microscopy and Confocal Reflectance Microscopy†

    Science.gov (United States)

    Lue, Niyom; Choi, Wonshik; Popescu, Gabriel; Yaqoob, Zahid; Badizadegan, Kamran; Dasari, Ramachandra R.; Feld, Michael S.

    2010-01-01

    Quantitative chemical analysis has served as a useful tool for understanding cellular metabolisms in biology. Among many physical properties used in chemical analysis, refractive index in particular has provided molecular concentration that is an important indicator for biological activities. In this report, we present a method of extracting full-field refractive index maps of live cells in their native states. We first record full-field optical thickness maps of living cells by Hilbert phase microscopy and then acquire physical thickness maps of the same cells using a custom-built confocal reflectance microscope. Full-field and axially averaged refractive index maps are acquired from the ratio of optical thickness to physical thickness. The accuracy of the axially averaged index measurement is 0.002. This approach can provide novel biological assays of label-free living cells in situ. PMID:19803506

  6. In vivo reflectance-mode confocal microscopy in clinical dermatology and cosmetology.

    Science.gov (United States)

    González, S; Gilaberte-Calzada, Y

    2008-02-01

    In vivo reflectance confocal microscopy (RCM) is a non-invasive imaging tool that allows real-time visualization of cells and structures in living skin with near histological resolution. RCM has been used for the assessment of benign and malignant lesions, showing great potential for applications in basic skin research and clinical dermatology. RCM also reveals dynamic changes in the skin over time and in response to specific stimuli, like ultraviolet exposure, which makes it a promising tool in cosmetology, as it allows repetitive sampling without biopsy collection, causing no further damage to the areas under investigation. This review summarizes the latest advances in RCM, and its applications in the characterization of both normal and pathological skin.

  7. Consistency and distribution of reflectance confocal microscopy features for diagnosis of cutaneous T cell lymphoma

    Science.gov (United States)

    Lange-Asschenfeldt, Susanne; Babilli, Jasmin; Beyer, Marc; Ríus-Diaz, Francisca; González, Salvador; Stockfleth, Eggert; Ulrich, Martina

    2012-01-01

    Reflectance confocal microscopy (RCM) represents a noninvasive imaging technique that has previously been used for characterization of mycosis fungoides (MF) in a pilot study. We aimed to test the applicability of RCM for diagnosis and differential diagnosis of MF in a clinical study. A total of 39 test sites of 15 patients with a biopsy-proven diagnosis of either MF, parapsoriasis, Sézary syndrome, or lymphomatoid papulosis were analyzed for presence and absence of RCM features of MF. Cochran and Chi2 analysis were applied to test the concordance between investigators and the distribution of RCM features, respectively. For selected parameters, the Cochran analysis showed good concordance between investigators. Inter-observer reproducibility was highest for junctional atypical lymphocytes, architectural disarray, and spongiosis. Similarly, Chi2 analysis demonstrated that selected features were present at particularly high frequency in individual skin diseases, with values ranging from 73% to 100% of all examined cases.

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

    International Nuclear Information System (INIS)

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

    1980-01-01

    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 Momarski 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

  9. Reflectance confocal microscopy features of seborrheic dermatitis for plaque psoriasis differentiation.

    Science.gov (United States)

    Agozzino, Marina; Berardesca, Enzo; Donadio, Carlo; Franceschini, Chiara; de Felice, Catia Margarete; Cavallotti, Claudia; Sperduti, Isabella; Ardigò, Marco

    2014-01-01

    Plaque psoriasis (PP) and seborrheic dermatitis (SD) are chronic inflammatory skin diseases with similar clinical and pathological features. Differential diagnosis can be difficult, especially when particular skin areas of the face are involved. Reflectance confocal microscopy (RCM) has been demonstrated to be useful for 'real-time' diagnosis of skin inflammatory diseases. To define distinctive confocal criteria of SD and to evaluate the usefulness of this technique for noninvasive differential diagnosis with PP. A total of 40 patients affected by PP and 19 patients by SD involving the face were recruited and subjected to RCM evaluation. Univariate and adjusted odds ratios were calculated. Discriminant functions were used to plot ROC curves. The results disclosed specific patterns for SD and PP. The following distinctive confocal features for SD have been identified: spongiosis, dermal inflammation and horizontal orientation of dilated blood vessels. SD has a specific and easily recognizable confocal pattern supporting clinical differentiation with PP.

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

    Science.gov (United States)

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

    2014-10-01

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

  11. Fully integrated reflection-mode photoacoustic, two-photon, and second harmonic generation microscopy in vivo

    Science.gov (United States)

    Song, Wei; Xu, Qiang; Zhang, Yang; Zhan, Yang; Zheng, Wei; Song, Liang

    2016-08-01

    The ability to obtain comprehensive structural and functional information from intact biological tissue in vivo is highly desirable for many important biomedical applications, including cancer and brain studies. Here, we developed a fully integrated multimodal microscopy that can provide photoacoustic (optical absorption), two-photon (fluorescence), and second harmonic generation (SHG) information from tissue in vivo, with intrinsically co-registered images. Moreover, using a delicately designed optical-acoustic coupling configuration, a high-frequency miniature ultrasonic transducer was integrated into a water-immersion optical objective, thus allowing all three imaging modalities to provide a high lateral resolution of ~290 nm with reflection-mode imaging capability, which is essential for studying intricate anatomy, such as that of the brain. Taking advantage of the complementary and comprehensive contrasts of the system, we demonstrated high-resolution imaging of various tissues in living mice, including microvasculature (by photoacoustics), epidermis cells, cortical neurons (by two-photon fluorescence), and extracellular collagen fibers (by SHG). The intrinsic image co-registration of the three modalities conveniently provided improved visualization and understanding of the tissue microarchitecture. The reported results suggest that, by revealing complementary tissue microstructures in vivo, this multimodal microscopy can potentially facilitate a broad range of biomedical studies, such as imaging of the tumor microenvironment and neurovascular coupling.

  12. Fast intracellular motion (FIM) as revealed by the reflection mode of video rate confocal laser scanning microscopy

    Czech Academy of Sciences Publication Activity Database

    Veselý, Pavel

    2005-01-01

    Roč. 40, č. 1 (2005), s. 34 ISSN 0035-9017. [Cytokinematics 2004. International Symposium on Microscopy of Live Cells in the Post Genomics Era /8./. 05.09.2004-07.09.2004, Hradec Králové] Institutional research plan: CEZ:AV0Z5052915 Keywords : FIM * video rate confocal laser scanning microscopy Subject RIV: EB - Genetics ; Molecular Biology

  13. New prism ring laser design incorporating frustrated total internal reflection output coupling

    DEFF Research Database (Denmark)

    Heyde, C.; Hansen, P.L.; Buchhave, Preben

    1997-01-01

    A novel prism ring laser design incorporating total internal reflection resonator mirrors and frustrated total internal reflection output coupling is analyzed and tested experimentally.......A novel prism ring laser design incorporating total internal reflection resonator mirrors and frustrated total internal reflection output coupling is analyzed and tested experimentally....

  14. Thin-film-based sensitivity enhancement for total internal reflection fluorescence live-cell imaging.

    Science.gov (United States)

    Kim, Kyujung; Cho, Eun-Jin; Huh, Yong-Min; Kim, Donghyun

    2007-11-01

    We investigated experimentally the evanescent field enhancement based on dielectric thin films in total internal reflection microscopy. The sample employed two layers of Al2O3 and SiO2 deposited on an SF10 glass substrate. Field intensity enhancement measured by fluorescent excitation of microbeads relative to that of a control sample without dielectric films was polarization dependent, determined as 4.2 and 2.4 for TE and TM polarizations, respectively, and was in good agreement with numerical results. The thin-film-based field enhancement was also applied to live-cell imaging of quantum dots, which confirmed the sensitivity enhancement qualitatively.

  15. Learning reflectance confocal microscopy of melanocytic skin lesions through histopathologic transversal sections.

    Directory of Open Access Journals (Sweden)

    Juliana Casagrande Tavoloni Braga

    Full Text Available Histopathologic interpretation of dermoscopic and reflectance confocal microscopy (RCM features of cutaneous melanoma was timidly carried out using perpendicular histologic sections, which does not mimic the same plane of the image achieved at both techniques (horizontal plane. The aim of this study was to describe the transverse histologic sections research technique and correlate main dermoscopic features characteristic of cutaneous melanoma (atypical network, irregular globules and pseudopods with RCM and histopathology in perpendicular and transverse sections in order to offer a more precise interpretation of in vivo detectable features. Four melanomas and 2 nevi with different dermoscopic clues have been studied. Lesion areas that showed characteristic dermoscopic features were imaged by dermoscopy and confocal microscopy and directly correlated with histopathology in perpendicular and transverse sections. We presented the possibility to perform transverse sections as a new approach to understand RCM features. Atypical network showed different aspects in the 2 melanomas: in one case it was characterized by pleomorphic malignant melanocytes with tendency to form aggregates, whereas in the other elongated dendritic cells crowded around dermal papillae, some of them forming bridges that resembled the mitochondrial aspect at confocal and histopathology transversal sections. Pigment globules in melanomas and nevi differed for the presence of large atypical cells in the former, and pseudopods showed up as elongated nests protruded toward the periphery of the lesion. Transverse histologic research sections have a consistent dermoscopic and confocal correlate, and it may represent an help in confocal feature interpretation and an advance in improving melanoma diagnosis and knowledge of the biology of melanocytic lesions.

  16. Videodermoscopy compared to reflectance confocal microscopy for the diagnosis of scabies.

    Science.gov (United States)

    Cinotti, E; Labeille, B; Cambazard, F; Biron, A C; Chol, C; Leclerq, A; Jaffelin, C; Perrot, J L

    2016-09-01

    Reflectance confocal microscopy (RCM) and dermoscopy have recently been suggested for non-invasive diagnosis of scabies. However, there are large studies on diagnostic accuracy for scabies only with dermoscopy at low (10×) and high (100-1000×) magnification. Our study evaluated the diagnostic accuracy, for the diagnosis of scabies, of RCM and videodermoscopy at intermediate (20× and 70×) magnification, which is usually found in commercially available videodermoscopes. Patients with a presumptive diagnosis of scabies were prospectively enrolled during 20 months and examined by RCM and videodermoscopy at intermediate magnification. The specificity of RCM was considered 100% because RCM can identify the anatomical details of the parasites. A total of 148 patients were enrolled. Videodermoscopy showed a higher sensitivity for scabies than RCM (95% vs. 92%) and a specificity of 97%. Videodermoscopy at intermediate magnification, and RCM are both highly accurate for the diagnosis of scabies. If the two devices are available, it would be better to perform videodermoscopy first, that is more sensitive, and then RCM to confirm the diagnosis. © 2016 European Academy of Dermatology and Venereology.

  17. Grading keratinocyte atypia in actinic keratosis: a correlation of reflectance confocal microscopy and histopathology.

    Science.gov (United States)

    Pellacani, G; Ulrich, M; Casari, A; Prow, T W; Cannillo, F; Benati, E; Losi, A; Cesinaro, A M; Longo, C; Argenziano, G; Soyer, H P

    2015-11-01

    Actinic Keratosis (AK) is the clinical manifestation of cutaneous dysplasia of epidermal keratinocytes, with progressive trend towards squamous cell carcinoma. To evaluate the strength of the correlation between keratinocyte atypia, as detected by Reflectance Confocal Microscopy (RCM) and histopathology, and to develop a more objective atypia grading scale for RCM quantification, through a discrete ranking. A total of 48 AKs and two control areas (photodamaged and non-photodamaged skin) were selected for this study. All these areas were documented by RCM and biopsied for histopathology. One representative image of the epidermis was selected for RCM and for histopathology and used for side-by-side comparison with purpose written software. The assessor chose which of two images displayed more keratinocyte atypia, and an ordered list from the image showing the least to the most keratinocyte atypia was generated. Three evaluations were obtained for RCM and two for histopathology. Good interobserver correlation was obtained for RCM and histopathology grading, with high concordance between RCM and histopathology grading. Expert rater scan consistently distinguish different grades of cytological atypia. Non-invasive RCM data from in vivo imaging can be graded for keratinocyte atypia, comparable to histopathological grading. © 2015 European Academy of Dermatology and Venereology.

  18. Pseudoxanthoma elasticum and reflectance confocal microscopy: report of two affected young sisters

    Directory of Open Access Journals (Sweden)

    Victor Desmond Mandel

    2015-04-01

    Full Text Available Pseudoxanthoma elasticum (PXE is a rare inherited multisystem disorder that mainly affects skin, eyes and cardiovascular system. The associated clinical signs are due to progressive calcification of elastic fibres and blood vessels, despite normal levels of calcium and phosphorus in blood and urine. The first clinical description of the disease was done in 1881 by Rigal, and in 1896 it was named PXE by Darier. Transmission of the disease is autosomal recessive. PXE is caused by homozygous or compound heterozygous mutations in the ATP-binding cassette subfamily C member 6 (ABCC6 gene, which encodes a transmembrane transport ADP-dependent protein (MRP6. The gene is expressed predominantly in the liver and kidney, and found in low level in the tissue involved by PXE. The clinical expression of PXE is heterogeneous with considerable variation in age of onset, progression and severity of the disease, even in individuals of the same family with identical mutations.We present the case of two young sisters affected by PXE and the correlation between the histopathology and the reflectance confocal microscopy (RCM. Parents and brother carry one copy of the mutated gene, without showing signs and symptoms of the disorder. We report the main clinical aspects of PXE and we highlight the importance of early diagnosis of the disease for adequate therapeutical management of associated complications.

  19. In vivo reflectance confocal microscopy detects pigmentary changes in melasma at a cellular level resolution.

    Science.gov (United States)

    Kang, Hee Young; Bahadoran, Philippe; Suzuki, Itaru; Zugaj, Didier; Khemis, Abdallah; Passeron, Thierry; Andres, Philippe; Ortonne, Jean-Paul

    2010-08-01

    Melasma is a frequent pigmentary disorder caused by abnormal melanin deposits in the skin. In vivo reflectance confocal microscopy (RCM) is a repetitive imaging tool that provides real-time images of the skin at nearly histological resolution. As melanin is the strongest endogenous contrast in human skin, pigmentary disorders are the most suitable candidates for RCM examination but RCM features of melasma have never been reported. This study investigates the pilot use of RCM in melasma to provide a set of well-described morphological criteria with histological correlations. RCM images were acquired from melasma skin and compared to adjacent control skin in 26 patients. Skin biopsies were obtained from eight patients. In the epidermis, RCM showed in all patients a significant increase in hyperrefractile cobblestoning cells. These cells corresponded to hyperpigmented basal keratinocytes in histology. In six patients, dendritic cells corresponding to activated melanocytes were also found in the epidermis. In the dermis, RCM identified in nine patients plump bright cells corresponding to melanophages. Interestingly, for a given patient, the topographic distribution of melanophages in melasma lesions was very heterogeneous. RCM also showed a significant increase in solar elastosis and blood vessels in the dermis. RCM is a non-invasive technique that detects pigmentary changes in melasma at a cellular level resolution. Therefore, RCM provides an innovative way to classify melasma by pigment changes.

  20. [In vivo reflectance confocal microscopy in dermatology: a proposal concerning French terminology].

    Science.gov (United States)

    Kanitakis, J; Bahadoran, P; Braun, R; Debarbieux, S; Labeille, B; Perrot, J-L; Vabres, P

    2013-11-01

    Reflectance confocal microscopy (RCM) is a recently introduced non-invasive imaging technique allowing real-time examination of the skin in vivo. Whereas a substantial literature concerning RCM exists in English, so far there is no official terminology in French, despite the fact that an ever-growing number of French-speaking dermatologists now use this new imaging technique. The aim of the present study is to propose a French terminology for RCM in order to allow French-speaking dermatologists to communicate in a precise and homogeneous language on this topic. A group of French-speaking dermatologists with solid experience of RCM, members of the Non-invasive Cutaneous Imaging group of the French Society of Dermatology, endeavored to suggest terms in French concerning RCM. Each group member dealt with a specific paragraph. The members exchanged comments via email and the terminology was finalized during a meeting of the group members in Paris in June 2012. Descriptive terms referring to the RCM aspects of normal and diseased skin were proposed. Some of these already existed, being used in routine dermatopathology, while other specific terms were created or adapted from the English terminology. This terminology will allow French-speaking dermatologists using RCM to communicate their findings in a homogeneous language. It may be enriched in the future by the introduction of additional terms describing new aspects of both normal and, especially, diseased skin. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  1. The significance of reflectance confocal microscopy in the assessment of solitary pink skin lesions.

    Science.gov (United States)

    Braga, Juliana Casagrande Tavoloni; Scope, Alon; Klaz, Itay; Mecca, Patricia; González, Salvador; Rabinovitz, Harold; Marghoob, Ashfaq A

    2009-08-01

    Solitary pink lesions often manifest nondescript clinical and dermatoscopic primary morphologic features. The differential diagnosis for pink lesions tends, therefore, to be broad, ranging from inflammatory processes to malignancy. In vivo reflectance confocal microscopy (RCM) may help in the evaluation of pink lesions. We sought to demonstrate the use of RCM as an adjunct to the bedside diagnosis of pink lesions. We describe a series of patients with clinically and dermatoscopically equivocal pink lesions for which RCM examination allowed for a rapid and accurate diagnosis. All lesions were excised for histopathologic evaluation. Integrating the findings in the case series with a literature review, we present RCM diagnostic criteria for pink lesions. Lesions included basal cell carcinoma, squamous cell carcinoma, amelanotic melanoma, and inflamed seborrheic keratosis. RCM shows distinctive findings for each diagnostic entity when stratified by anatomic level into suprabasal epidermis, dermoepidermal junction, and papillary dermis. In the cases presented RCM allowed for a rapid and accurate noninvasive diagnosis. The study is descriptive and does not test accuracy of RCM criteria in a prospective series of pink lesions. RCM may add useful diagnostic features to the clinical evaluation of solitary pink lesions.

  2. DIRC, the internally reflecting ring imaging Cherenkov detector for BABAR

    International Nuclear Information System (INIS)

    Adam, I.; Aston, D.

    1997-11-01

    The DIRC is a new type of Cherenkov imaging device that will be used for the first time in the BABAR detector at the asymmetric B-factory, PEP-II. It is based on total internal reflection and uses long, rectangular bars made from synthetic fused silica as Cherenkov radiator and light guide. The principles of the DIRC ring imaging Cherenkov technique are explained and results from the prototype program are presented. Its choice for the BABAR detector particle identification system is motivated, followed by a discussion of the quartz radiator properties and the detector design

  3. Smooth and rough Proteus mirabilis lipopolysaccharides studied by total internal reflection ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Gleńska-Olender, J., E-mail: joannaglenska@wp.pl [Institute of Biology, Jan Kochanowski University, 25-406 Kielce (Poland); Świętokrzyski Biobank, Regional Science and Technology Center, 26-060 Chęciny (Poland); Dworecki, K. [Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Sęk, S. [Department of Chemistry, University of Warsaw, 02-093 Warsaw (Poland); Kwinkowski, M.; Kaca, W. [Institute of Biology, Jan Kochanowski University, 25-406 Kielce (Poland)

    2013-12-02

    Total internal reflection ellipsometry (TIRE), a label-free optical detection technique for studying interactions between biomolecules, was used to examine the adsorption of various forms of lipopolysaccharides (LPSs) isolated from Proteus mirabilis S1959, R110, and R45 strains on a gold surface. The thickness of the adsorbed layers was determined by TIRE, with the average values for S1959, R110, and R45 LPS layers being 78 ± 5, 39 ± 3, and 12 ± 2 nm, respectively. The thickness of LPS layers corresponds to the presence and length of O-specific parts in P. mirabilis LPS molecules. Atomic force microscopy was used as a complementary technique for visualizing lipopolysaccharides on the surface. Force measurements seem to confirm the data obtained from TIRE experiments. - Highlights: • Proteus mirabilis lipopolysaccharides were adsorbed on the gold surface. • Thickness of adsorbed layers was determined by total internal reflection ellipsometry. • Atomic force microscopy was used to visualize lipopolysaccharide build-up on gold surface. • Time is important in the evolution of biomolecular film thickness created on gold surface.

  4. Determination of lead in clay enameled by X-ray fluorescence technique in Total reflection and by Scanning Electron Microscopy

    International Nuclear Information System (INIS)

    Zarazua O, G.; Carapia M, L.

    2000-01-01

    This work has the objective of determining lead free in the glazed commercial stewing pans using the X-ray fluorescence technique in Total reflection (FRX) and the observation and semiquantitative determination of lead by Analytical Scanning Electron Microscopy (ASEM). (Author)

  5. Combining tape stripping and non-invasive reflectance confocal microscopy : an in vivo model to study skin damage

    NARCIS (Netherlands)

    Peppelman, M.; Eijnde, W.A. van den; Jaspers, E.J.; Gerritsen, M.J.P.; Erp, P.E.J. van

    2015-01-01

    BACKGROUND: Evaluation of (immuno)histological and cell biological changes in damaged skin requires often an invasive skin biopsy, making in vivo models inappropriate to study skin damage. Reflectance confocal microscopy (RCM) might overcome this limitation. Therefore, we evaluated the use of a

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    Background and Objective Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) offer high-resolution optical imaging of the skin, which may provide benefit in the context of laser-assisted drug delivery. We aimed to characterize postoperative healing of ablative fractional...

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

    NARCIS (Netherlands)

    Banzhaf, Christina A.; Wind, Bas S.; Mogensen, Mette; Meesters, Arne A.; Paasch, Uwe; Wolkerstorfer, Albert; Haedersdal, Merete

    2016-01-01

    Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) offer high-resolution optical imaging of the skin, which may provide benefit in the context of laser-assisted drug delivery. We aimed to characterize postoperative healing of ablative fractional laser (AFXL)-induced

  8. The reflectance confocal microscopy features of sebaceous adenoma in a case of Muir Torre syndrome

    Directory of Open Access Journals (Sweden)

    Esma İnan Yüksel

    2015-03-01

    Full Text Available Muir-Torre syndrome (MTS is a rare autosomal dominant genodermatosis characterized by the occurrence of sebaceous gland neoplasms and/or keratoacanthomas associated with visceral malignancies. It is considered as a subtype of hereditary nonpolyposis colorectal cancer syndrome. Characteristic sebaceous gland neoplasms include sebaceous adenoma, sebaceous carcinoma, sebaceoma, and keratoacanthoma with sebaceous differentiation. The most common visceral malignancies are colorectal and genitourinary tumors. CASE: A 47year-old male patient admitted to our clinic complaining of two lesions on the nose. Dermatological examination revealed a plaque in 1 cm diameter consisting of bright yellowish-white coloured papules with slightly umblicated appearance and telangiectasias on the left site of the nose and had a dome shaped papule in 3 mm diameter with hyperkeratotic plug on the tip of the nose. He had personal history of partial colon resection because of colon cancer and familial Lynch 2 syndrome. On dermoscopic examination of sebaceous adenoma, a few yellow comedo-like globules and branching arborizing vessels were detected. Reflectance confocal microscopy (RCM revealed a good histopathologic correlation. Sebaceous lobules were composed by clusters of ovoid cells with hyporefractile dark nuclei and bright, hyperrefractile glistening cytoplasm. Numerous roundish to ovoid dark spaces corresponding to sebaceous ducts were detected. The diagnosis of MTS was established based on the personal and family history, dermoscopic, RCM and histopathologic findings. CONCLUSIONS: MTS evaluation is required in patients with biopsy-proven sebaceous adenoma. Early diagnosis may be lifesaving in patients with MTS. A better characterization of RCM features of sebaceous tumors will allow early diagnosis of the patients with MTS.

  9. THE MECHANISM OF ADHESION OF CELLS TO GLASS. A STUDY BY INTERFERENCE REFLECTION MICROSCOPY.

    Science.gov (United States)

    CURTIS, A S

    1964-02-01

    An optical technique for measuring the thickness of thin films has been adapted and evaluated for studying the structure of the adhesion of cells to glass in tissue culture. This technique, which is termed interference reflection microscopy, has been used to study embryonic chick heart fibroblasts. These findings have been observed: in normal culture medium the closest approach of the cell surface to substrate in its adhesions is ca. 100 A, much of the cell surface lying farther away; chemical treatments which bring the cell surface to near its charge reversal point reduce the closest approach of adhesions to glass in the adhesions. When cells de-adhere from glass, they appear not to leave fragments behind. The adhesive sites in these fibroblasts appear to be confined to the edge of the side of the cell facing the substrate and to the pseudopods. The significance of this is discussed in relation to the phenomenon of contact inhibition. Evidence is presented that the mechanism of cell adhesion does not involve calcium atoms binding cells to substrate by combining with carboxyl groups on cell surface, substrate, and with a cement substance. Osmium tetroxide fixation results in a final separation of 100 to 200 A between cell and substrate: there are reasons for thinking that this fairly close approach to the condition in life is produced as an artefact. The results can be accounted for only in terms of the action of electrostatic repulsive forces and an attractive force, probably the van der Waals-London forces. Biological arguments suggest that these results are equally applicable for cell-to-cell adhesions.

  10. Reflectance confocal microscopy-guided laser ablation of basal cell carcinomas: initial clinical experience

    Science.gov (United States)

    Sierra, Heidy; Yélamos, Oriol; Cordova, Miguel; Chen, Chih-Shan Jason; Rajadhyaksha, Milind

    2017-08-01

    Laser ablation offers a procedure for precise, fast, and minimally invasive removal of superficial and early nodular basal cell carcinomas (BCCs). However, the lack of histopathological confirmation has been a limitation toward widespread use in the clinic. A reflectance confocal microscopy (RCM) imaging-guided approach offers cellular-level histopathology-like feedback directly on the patient, which may then guide and help improve the efficacy of the ablation procedure. Following an ex vivo benchtop study (reported in our earlier papers), we performed an initial study on 44 BCCs on 21 patients in vivo, using a pulsed erbium:ytterbium aluminum garnet laser and a contrast agent (aluminum chloride). In 10 lesions on six patients, the RCM imaging-guided detection of either presence of residual tumor or complete clearance was immediately confirmed with histopathology. Additionally, 34 BCCs on 15 patients were treated with RCM imaging-guided laser ablation, with immediate confirmation for clearance of tumor (no histopathology), followed by longer-term monitoring, currently in progress, with follow-up imaging (again, no histopathology) at 3, 6, and 18 months. Thus far, the imaging resolution appears to be sufficient and consistent for monitoring efficacy of ablation in the wound, both immediately postablation and subsequently during recovery. The efficacy results appear to be promising, with observed clearance in 19 cases of 22 cases with follow-ups ranging from 6 to 21 months. An additional 12 cases with 1 to 3 months of follow-ups has shown clearance of tumor but a longer follow-up time is required to establish conclusive results. Further instrumentation development will be necessary to cover larger areas with a more automatically controlled instrument for more uniform, faster, and deeper imaging of margins.

  11. Reflectance confocal microscopy for quantification of Sarcoptes scabiei in Norwegian scabies.

    Science.gov (United States)

    Cinotti, E; Perrot, J L; Labeille, B; Vercherin, P; Chol, C; Besson, E; Cambazard, F

    2013-02-01

    In vivo reflectance-mode confocal microscopy (RCM) can be used for the diagnosis of scabies. This study quantifies S. scabiei and its eggs and droppings in a patient affected by Norwegian Scabies (NS), and describes their distribution within the epidermis and in different body areas. Different skin sites were randomly chosen in four sections (head, upper limbs, trunk and inferior limbs) of the body surface area (BSA) to acquire a total of 60 RCM z-stacks. The number of mites and eggs, the presence of droppings, as well as the minimum epidermal depth at which mites, eggs and faeces were detectable, was established for each z-stack. The total number of mites and eggs on the entire BSA was calculated considering the weighted mean for the four sections of the BSA. A total of 15.8 millions of S. scabiei and 7.2 millions of eggs were calculated. Mites, eggs and faeces were homogeneously distributed all over the body surface. Droppings, easily recognized by the RCM, were present in more than an half of the analyzed cutaneous sites and were associated with the presence of parasites (chi-squared test, P = 0.002). Our study illustrates the ability of RCM to identify, locate, and quantify the various forms of S. scabiei in human skin. NS is an extremely contagious disease, considering that the number of mites can be around 15.8 millions. Moreover, all areas of the body are parasitized in NS, including the face. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.

  12. Detection of living Sarcoptes scabiei larvae by reflectance mode confocal microscopy in the skin of a patient with crusted scabies

    Science.gov (United States)

    Levi, Assi; Mumcuoglu, Kosta Y.; Ingber, Arieh; Enk, Claes D.

    2012-06-01

    Scabies is an intensely pruritic disorder induced by a delayed type hypersensitivity reaction to infestation of the skin by the mite Sarcoptes scabiei. The diagnosis of scabies is established clinically and confirmed by identifying mites or eggs by microscopic examination of scrapings from the skin or by surface microscopy using a dermatoscope. Reflectance-mode confocal microscopy is a novel technique used for noninvasive imaging of skin structures and lesions at a resolution compatible to that of conventional histology. Recently, the technique was employed for the confirmation of the clinical diagnosis of scabies. We demonstrate the first ever documentation of a larva moving freely inside the skin of a patient infected with scabies.

  13. 'En face' ex vivo reflectance confocal microscopy to help the surgery of basal cell carcinoma of the eyelid.

    Science.gov (United States)

    Espinasse, Marine; Cinotti, Elisa; Grivet, Damien; Labeille, Bruno; Prade, Virginie; Douchet, Catherine; Cambazard, Frédéric; Thuret, Gilles; Gain, Philippe; Perrot, Jean Luc

    2017-07-01

    Ex vivo confocal microscopy is a recent imaging technique for the perioperative control of skin tumour margins. Up to date, it has been used in the fluorescence mode and with vertical sections of the specimen margins. The aim of this study was to evaluate its use in the reflectance mode and with a horizontal ('en face') scanning of the surgical specimen in a series of basal cell carcinoma of the eyelid. Prospective consecutive cohort study was performed at the University Hospital of Saint-Etienne, France. Forty-one patients with 42 basal cell carcinoma of the eyelid participated in this study. Basal cell carcinomas were excised with a 2-mm-wide clinically safe margin. The surgical specimens were analysed under ex vivo confocal microscopy in the reflectance mode and with an en face scanning in order to control at a microscopic level if the margins were free from tumour invasion. Histopathogical examination was later performed in order to compare the results. Sensitivity and specificity of ex vivo confocal microscopy for the presence of tumour-free margins. Ex vivo confocal microscopy results were consistent with histopathology in all cases (tumour-free margins in 40 out of 42 samples; sensitivity and specificity of 100%). Ex vivo confocal microscopy in the reflectance mode with an 'en face' scanning can control tumour margins of eyelid basal cell carcinomas and optimize their surgical management. This procedure has the advantage on the fluorescent mode of not needing any contrast agent to examine the samples. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

  14. Coherent artifact suppression in line-field reflection confocal microscopy using a low spatial coherence light source.

    Science.gov (United States)

    Liu, Changgeng; Cao, Hui; Choma, Michael A

    2016-10-15

    Line-field reflection confocal microscopy (LF-RCM) has the potential to add a dimension of parallelization to traditional confocal microscopy while reducing the need for two-axis beam scanning. LF-RCM systems often employ light sources with a high degree of spatial coherence. This high degree of spatial coherence potentially leads to unwanted coherent artifact in the setting of nontrivial sample scattering. Here, we (a) confirm that a coherent artifact is a nontrivial problem in LF-RCM when using spatially coherent light, and (b) demonstrate that such a coherent artifact can be mitigated through the use of reduced spatial coherence line-field sources. We demonstrate coherent noise suppression in a full-pupil line-field confocal microscope using a large number of mutually incoherent emitters from a vertical-cavity surface-emitting lasers (VCSEL) array. The coherent noise from a highly scattering sample is significantly suppressed by the use of this synthesized reduced spatial coherence light source compared to a fully coherent light source. Lastly, with scattering samples, the axial confocality of line-field confocal microscopy is compromised independent of the source spatial coherence, as demonstrated by our experimental result. Our results highlight the importance of spatial coherence engineering in parallelized reflection confocal microscopy.

  15. Real time and non-destructive analysis of tablet coating thickness using acoustic microscopy and infrared diffuse reflectance spectroscopy.

    Science.gov (United States)

    Bikiaris, D; Koutri, I; Alexiadis, D; Damtsios, A; Karagiannis, G

    2012-11-15

    Tablet coating thicknesses were estimated using several techniques such as weight gain and scanning electron microscopy (SEM), in comparison with acoustic microscopy and diffuse reflectance spectroscopy. Acoustic microscopy, used for the first time in such an application, is based on the physical phenomenon of ultrasound propagation through the materials and the echoes generated by their interfaces. Based on the time of flights (TOFs) of the echoes from the coating surface and the tablet, it is possible to calculate the coating thickness. In order to evaluate the accuracy and robustness of these methods, drug tablets were coated with Kollicoat SR polymer for several times, so that to prepare tablets with different coating thicknesses. Tablets with 3, 6 and 9 wt% coating material have been prepared and based on SEM micrographs it was found that the tablet coating thickness is 71.99 ± 1.2 μm, 92.5 ± 1.7 μm and 132.3 ± 2.1 μm, respectively (SEM analysis). The tablet coating thicknesses measured with acoustic microscopy and infrared diffuse reflectance spectroscopy, were in agreement with those obtained using SEM. This verifies that both techniques can be successfully applied for real time and non-destructive thickness measurements of tablet coating. Furthermore, both techniques, compared with SEM and weight gained measurements, are fast and fully automated. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Investigation of the internal reflectance and prediction of infrared diffuse reflectance of the polymeric coating on aluminum substrate

    Science.gov (United States)

    Ho, Wen-Dar; Ma, Chen-Chi M.

    1998-02-01

    This study employs the ray tracing method to develop and analyze mathematical formulae for the IR diffuse reflectance of the polymeric coating on a metal substrate. The effects of the thickness and the absorption property of the polymer film on the internal reflectance are also investigated. In addition, the diffuse reflectance of the coating/substrate system which is irradiated with a perfect diffuse source is formulated as well. Analysis results indicate that the internal reflectance of the internal front surface (polymer/air interface) is not a constant which depends on the film thickness and absorption property. Closely examining the internal multiple reflections between the front and the substrate surface reveals that the diffuse reflectance of the coating/substrate system can be obtained by summing the fractions of rays emerging from the front surface. By knowing the refractive index and the extinction coefficient of the polymer, the diffuse reflectance of the coating/substrate system can be calculated by the formulae presented here. In addition an alkyd resin coating/aluminum substrate system is also implemented to compare the experimental reflectances with the calculated ones. According to the comparisons the analysis and developed formulae are quite effective.

  17. Polarization contrast in fluorescence scanning near-field optical microscopy in reflection

    NARCIS (Netherlands)

    Jalocha, A.; Jalocha, A.; van Hulst, N.F.

    1995-01-01

    Polarization contrast is presented in fluorescence images of a Langmuir-Blodgett monolayer obtained with a scanning near-field optical microscope operated in reflection. A tapered optical fiber is used both to excite and to collect the fluorescence. The lateral resolution in the reflection

  18. Value of Online Group Reflection After International Service-Learning Experiences: I Never Thought of That.

    Science.gov (United States)

    Smit, Eileen M; Tremethick, Mary Jane

    Reflection is a widely accepted learning tool and a component of competent professional practice. An exploratory descriptive study was conducted to compare the breadth and level of reflection between students engaged in individual reflection papers and students engaged in an online group reflection discussion after an international cultural immersion service-learning program. Results indicated that students participating in the online group discussion had a higher level of reflective thinking and discussed more topics in their written reflections.

  19. Spectral fingerprinting of individual cells visualized by cavity-reflection-enhanced light-absorption microscopy.

    Science.gov (United States)

    Arai, Yoshiyuki; Yamamoto, Takayuki; Minamikawa, Takeo; Takamatsu, Tetsuro; Nagai, Takeharu

    2015-01-01

    The absorption spectrum of light is known to be a "molecular fingerprint" that enables analysis of the molecular type and its amount. It would be useful to measure the absorption spectrum in single cell in order to investigate the cellular status. However, cells are too thin for their absorption spectrum to be measured. In this study, we developed an optical-cavity-enhanced absorption spectroscopic microscopy method for two-dimensional absorption imaging. The light absorption is enhanced by an optical cavity system, which allows the detection of the absorption spectrum with samples having an optical path length as small as 10 μm, at a subcellular spatial resolution. Principal component analysis of various types of cultured mammalian cells indicates absorption-based cellular diversity. Interestingly, this diversity is observed among not only different species but also identical cell types. Furthermore, this microscopy technique allows us to observe frozen sections of tissue samples without any staining and is capable of label-free biopsy. Thus, our microscopy method opens the door for imaging the absorption spectra of biological samples and thereby detecting the individuality of cells.

  20. Extending Whole Slide Imaging: Color Darkfield Internal Reflection Illumination (DIRI for Biological Applications.

    Directory of Open Access Journals (Sweden)

    Yoshihiro Kawano

    Full Text Available Whole slide imaging (WSI is a useful tool for multi-modal imaging, and in our work, we have often combined WSI with darkfield microscopy. However, traditional darkfield microscopy cannot use a single condenser to support high- and low-numerical-aperture objectives, which limits the modality of WSI. To overcome this limitation, we previously developed a darkfield internal reflection illumination (DIRI microscope using white light-emitting diodes (LEDs. Although the developed DIRI is useful for biological applications, substantial problems remain to be resolved. In this study, we propose a novel illumination technique called color DIRI. The use of three-color LEDs dramatically improves the capability of the system, such that color DIRI (1 enables optimization of the illumination color; (2 can be combined with an oil objective lens; (3 can produce fluorescence excitation illumination; (4 can adjust the wavelength of light to avoid cell damage or reactions; and (5 can be used as a photostimulator. These results clearly illustrate that the proposed color DIRI can significantly extend WSI modalities for biological applications.

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

    NARCIS (Netherlands)

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

    2015-01-01

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

  2. Darkfield-Confocal Microscopy detection of nanoscale particle internalization by human lung cells

    Directory of Open Access Journals (Sweden)

    Samet James M

    2011-01-01

    Full Text Available Abstract Background Concerns over the health effects of nanomaterials in the environment have created a need for microscopy methods capable of examining the biological interactions of nanoparticles (NP. Unfortunately, NP are beyond the diffraction limit of resolution for conventional light microscopy (~200 nm. Fluorescence and electron microscopy techniques commonly used to examine NP interactions with biological substrates have drawbacks that limit their usefulness in toxicological investigation of NP. EM is labor intensive and slow, while fluorescence carries the risk of photobleaching the sample and has size resolution limits. In addition, many relevant particles lack intrinsic fluorescence and therefore can not be detected in this manner. To surmount these limitations, we evaluated the potential of a novel combination of darkfield and confocal laser scanning microscopy (DF-CLSM for the efficient 3D detection of NP in human lung cells. The DF-CLSM approach utilizes the contrast enhancements of darkfield microscopy to detect objects below the diffraction limit of 200 nm based on their light scattering properties and interfaces it with the power of confocal microscopy to resolve objects in the z-plane. Results Validation of the DF-CLSM method using fluorescent polystyrene beads demonstrated spatial colocalization of particle fluorescence (Confocal and scattered transmitted light (Darkfield along the X, Y, and Z axes. DF-CLSM imaging was able to detect and provide reasonable spatial locations of 27 nm TiO2 particles in relation to the stained nuclei of exposed BEAS 2B cells. Statistical analysis of particle proximity to cellular nuclei determined a significant difference between 5 min and 2 hr particle exposures suggesting a time-dependant internalization process. Conclusions DF-CLSM microscopy is an alternative to current conventional light and electron microscopy methods that does not rely on particle fluorescence or contrast in electron

  3. Signal improvement in multiphoton microscopy by reflection with simple mirrors near the sample

    Science.gov (United States)

    Rehberg, Markus; Krombach, Fritz; Pohl, Ulrich; Dietzel, Steffen

    2010-03-01

    In conventional fluorescence or confocal microscopy, emitted light is generated not only in the focal plane but also above and below. The situation is different in multiphoton-induced fluorescence and multiphoton-induced higher harmonic generation. Here, restriction of signal generation to a single focal point permits that all emitted photons can contribute to image formation if collected, regardless of their path through the specimen. Often, the intensity of the emitted light is rather low in biological specimens. We present a method to significantly increase the fraction of photons collected by an epi (backward) detector by placing a simple mirror, an aluminum-coated coverslip, directly under the sample. Samples investigated include fluorescent test slides, collagen gels, and thin-layered, intact mouse skeletal muscles. Quantitative analysis revealed an intensity increase of second- and third-harmonic generated signal in skeletal muscle of nine- and sevenfold respectively, and of fluorescent signal in test slides of up to twofold. Our approach thus allows significant signal improvement also for situations were a forward detection is impossible, e.g., due to the anatomy of animals in intravital microscopy.

  4. Short-coherence in-line phase-shifting infrared digital holographic microscopy for measurement of internal structure in silicon

    Science.gov (United States)

    Xi, Teli; Dou, Jiazhen; Di, Jianglei; Li, Ying; Zhang, Jiwei; Ma, Chaojie; Zhao, Jianlin

    2017-06-01

    Short-coherence in-line phase-shifting digital holographic microscopy based on Michelson interferometer is proposed to measure internal structure in silicon. In the configuration, a short-coherence infrared laser is used as the light source in order to avoid the interference formed by the reference wave and the reflected wave from the front surface of specimen. At the same time, in-line phase-shifting configuration is introduced to overcome the problem of poor resolution and large pixel size of the infrared camera and improve the space bandwidth product of the system. A specimen with staircase structure is measured by using the proposed configuration and the 3D shape distribution are given to verify the effectiveness and accuracy of the method.

  5. Quantitation of cell-matrix adhesion using confocal image analysis of focal contact associated proteins and interference reflection microscopy.

    Science.gov (United States)

    Usson, Y; Guignandon, A; Laroche, N; Lafage-Proust, M H; Vico, L

    1997-08-01

    We have developed an approach for the quantitation of vinculin, a focal contact associated protein, based on a multimodal confocal microscopy and image analysis. Vinculin spot distribution was imaged in confocal fluorescence microscopy and the corresponding focal contacts were imaged in confocal interference reflection microscopy. These images were analyzed with a SAMBA image cytometer. The image analysis program provided 12 morphometric features describing cellular area, shape, and proportions of vinculin spots as well as six topographical features describing the distribution of vinculin and the relative overlap of vinculin and focal contacts. This approach was applied to the study of rat osteosarcoma cells submitted to mechanical stresses: successions of 2g and 0g accelerations during a series of parabolic flights. The measured features were assessed by means of correlation analysis and stepwise discriminant analysis. After correlation analysis, only ten parameters were retained. Quantitation of cell morphological parameters indicated that cell area was significantly affected by gravitational stresses as well as vinculin distribution. Cell area was reduced by 50% and vinculin spots were restricted to cell periphery. Cell adhesion measured by IRM decreased significantly in the first part of the flight and remained stable at the end of the flight. These results suggest that cell-matrix adhesion is affected by gravitational stresses. Image analysis provides useful tools to investigate focal adhesion re-organization under different physiological stimuli.

  6. Polarization contrast in reflection near-field optical microscopy with uncoated fibre tips

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.; Langbein, Wolfgang; Hvam, Jørn Märcher

    1999-01-01

    Using cross-hatched, patterned semiconductor surfaces and round 20-nm-thick gold pads on semiconductor wafers, we investigate the imaging characteristics of a reflection near-field optical microscope with an uncoated fibre tip for different polarization configurations and light wavelengths....... Is is shown that cross-polarized detection allows one to effectively suppress far-field components in the detected signal and to realise imaging of optical contrast on the sub-wavelength scale. The sensitivity window of our microscope, i.e. the scale on which near-field optical images represent mainly optical...

  7. An Arduino-Based Experiment Designed to Clarify the Transition to Total Internal Reflection

    Science.gov (United States)

    Atkin, Keith

    2018-01-01

    The topic of refraction and reflection of light at the boundary of transparent media is a fundamentally important one. The special case of total internal reflection is however commonly misrepresented in elementary textbooks. This paper addresses the problem and describes an experimental procedure for measuring and displaying reflected and…

  8. An Arduino-based experiment designed to clarify the transition to total internal reflection

    Science.gov (United States)

    Atkin, Keith

    2018-03-01

    The topic of refraction and reflection of light at the boundary of transparent media is a fundamentally important one. The special case of total internal reflection is however commonly misrepresented in elementary textbooks. This paper addresses the problem and describes an experimental procedure for measuring and displaying reflected and transmitted light intensities using readily available components and the Arduino microcontroller.

  9. Reflections on the law applicable to international oil contracts

    OpenAIRE

    Otero García-Castrillón, Carmen

    2013-01-01

    Business activity in the hydrocarbon sector, involving the extraction of natural resources essential to maintain our modern lifestyle, begins with the negotiation of oil and gas exploration and exploitation contracts. Apart from the traditional role of the parties’ contractual autonomy, determining the legal regime of these contracts necessitates considering the role of international law, the development of oil sector-specific international rules (lex petrolea), and the impact of the imperati...

  10. Accompanying Partners of International Students: Reflections on Three Issues

    Science.gov (United States)

    Cui, Dan; Arthur, Nancy; Domene, José F.

    2017-01-01

    This paper reviews and critiques the existing literature on accompanying partners of international students (APIS), who are often an ignored population in programs and services for the internationalization of Canadian higher education. Particularly, we identify three issues. First, we argue that current research on this group overwhelmingly…

  11. Maintaining International Peace and Security: Reflections on Peace ...

    African Journals Online (AJOL)

    produced a dramatic growth in peacekeeping requirements since the end of the previous decade. The international response, mainly through the United Nations (UN), has been to promote preventive diplomacy and, in a number of cases, to conduct peace-support operations. In brief, this paper points out that each UN ...

  12. Pedagogical Reflections on Internalizing Geopolitical Representations in Print Media

    Science.gov (United States)

    Abdul-Jabbar, Wisam Khalid

    2015-01-01

    This essay explores how print media conceals implicit hegemonic texts that common readers unsuspectingly tend to internalize. These geopolitically infused texts are set to appropriate the reader's worldviews by sublimating the kind of perceptions and notions they want to promote. This paper raises questions and awareness about how academia…

  13. Effect of the refraction factor of a plastic fiber shell on the internal reflection coefficient

    International Nuclear Information System (INIS)

    Pkrksypkin, A.I.; Ponomarev, L.I.

    1992-01-01

    Results of pilot studies of the effect of refraction factor of plastic fiber shell on the coefficient of light internal reflection in the fiber are presented. It is pointed, that the shell does not absorb the light, but effects the surface layer of the fiber centre so, that dependence of the coefficient of internal reflection on refraction factor of the shell may be described using Fresnel formulae. It is shown, that coefficient of internal reflection decreases with the increase of refraction factor. Technique to determine volume length of scintillation light absorption in the fiber is suggested

  14. Reflections on the development of international nuclear law

    International Nuclear Information System (INIS)

    Lamm, Vanda

    2017-01-01

    Over the course of more than seven decades, treaty norms on the production and utilisation of nuclear energy have been developed, which together form a special section within international law. These norms are the consequence of the unique nature of the field, namely that on the one hand some aspects of the uses of nuclear energy should be covered by totally new and special norms (e.g. in the field of disarmament, seeking to eliminate or at least to control the spread of nuclear weapons, and nuclear weapons tests) and on the other hand that several traditional legal solutions were not suitable for the problems that emerged in connection with other uses of nuclear energy (like liability). In this article, three aspects of the development of that special section of international law will be explored, namely: the close connections between the regulation of peaceful and military uses of nuclear energy; the effects of nuclear catastrophes on the development of international nuclear legislation; and the interaction between soft law norms and binding norms in the area of nuclear law

  15. Nursing student voices: reflections on an international service learning experience.

    Science.gov (United States)

    Main, E Eve; Garrett-Wright, Dawn; Kerby, Molly

    2013-01-01

    For the past decade participation in service and experiential learning in higher education has increased. The purpose of this study was to explore the lived experience of BSN and MSN students participating in a multidisciplinary service-learning course in a rural, underserved village in Belize. Researchers analyzed student journals utilizing qualitative data analysis techniques. There were eight consistent themes found in the student journals. The findings indicate that international service learning opportunities increase students' awareness of their place in a global society and the potential contribution they can make in society. For the past decade, service and experiential learning in higher education, including nursing education, has become increasingly important. Simply put, service and experiential learning combine community service activities with a student's academic study for the sole purpose of enriching the academic experience. As faculty, we feel the goal of baccalaureate and graduate nursing education is to produce an educated professional who will become a responsible citizen.

  16. Pedagogical Reflections on Internalizing Geopolitical Representations in Print Media

    Directory of Open Access Journals (Sweden)

    Wisam Khalid Abdul-Jabbar

    2015-06-01

    Full Text Available This essay explores how print media conceals implicit hegemonic texts that common readers unsuspectingly tend to internalize. These geopolitically infused texts are set to appropriate the reader’s worldviews by sublimating the kind of perceptions and notions they want to promote. This paper raises questions and awareness about how academia responds to these acts of internalization. These geopolitical texts, which dominate most of the print media and other resources, function at an imperceptible level to legitimize presuppositions and mould the world based on its own political imaginaries. To decode and interpret these largely shrewd texts requires a literacy skill that students need to acquire in different academic disciplines. This essay, therefore, explores how print media, such as newspapers and comics, attempts to legitimize knowledge through reports and stories that work at the subliminal level. Since all readers, students, instructors or researchers are vulnerable observers (Behar, 1996, because of our fallible human nature, the act of internalizing mediascaped knowledge becomes alarmingly simple and crucially effective on the way we are directed to perceive the world. By analogy, geopolitical texts are these id-instigated drives that the superego often suppresses and filters into dreams and fiction and yet they ominously somehow found their way out; they stealthily found expression and now they paint reality with their own biased colors. Can readers in the context be dream catchers? Cet article explore la manière dont les médias écrits dissimulent les textes hégémoniques implicites que les lecteurs ordinaires semblent assimiler à leur insu. Ces textes géopolitiquement insufflés sont appelés à approprier la vision du monde des lecteurs en sublimant le type de perceptions et de notions qu’ils souhaitent promouvoir. Cet article soulève des questions et sensibilise l’opinion sur la manière dont le monde universitaire r

  17. Topography and Mechanical Property Mapping of International Simple Glass Surfaces with Atomic Force Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M [ORNL

    2014-01-01

    Quantitative Nanomechanical Peak Force (PF-QNM) TappingModeTM atomic force microscopy measurements are presented for the first time on polished glass surfaces. The PF-QNM technique allows for topography and mechanical property information to be measured simultaneously at each pixel. Results for the international simple glass which represents a simplified version of SON68 glass suggests an average Young s modulus of 78.8 15.1 GPa is within the experimental error of the modulus measured for SON68 glass (83.6 2 GPa) with conventional approaches. Application of the PF-QNM technique will be extended to in situ glass corrosion experiments with the goal of gaining atomic-scale insights into altered layer development by exploiting the mechanical property differences that exist between silica gel (e.g., altered layer) and pristine glass surface.

  18. International Trade and Sustainable Development: Reflections on the Regulation Through the International Organizations

    OpenAIRE

    Barza, Eugênia Cristina Nilsen Ribeiro; Cerqueira, Wanilza Marques de Almeida

    2016-01-01

    The purpose of this study is to analyze the link between international trade and development. The regulation of international trade by international organizations will be explored. In the post-WTO scenario, there is the formation of a new governance in relation to international trade, with a tendency to appreciation of international relations at the Westphalian style. This phenomenon is worrying , especially in light of Agenda 2030 for Sustainable Development and the 17 Sustainable Developmen...

  19. Handheld optical coherence tomography-reflectance confocal microscopy probe for detection of basal cell carcinoma and delineation of margins

    Science.gov (United States)

    Iftimia, Nicusor; Yélamos, Oriol; Chen, Chih-Shan J.; Maguluri, Gopi; Cordova, Miguel A.; Sahu, Aditi; Park, Jesung; Fox, William; Alessi-Fox, Christi; Rajadhyaksha, Milind

    2017-07-01

    We present a hand-held implementation and preliminary evaluation of a combined optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) probe for detecting and delineating the margins of basal cell carcinomas (BCCs) in human skin in vivo. A standard OCT approach (spectrometer-based) with a central wavelength of 1310 nm and 0.11 numerical aperture (NA) was combined with a standard RCM approach (830-nm wavelength and 0.9 NA) into a common path hand-held probe. Cross-sectional OCT images and enface RCM images are simultaneously displayed, allowing for three-dimensional microscopic assessment of tumor morphology in real time. Depending on the subtype and depth of the BCC tumor and surrounding skin conditions, OCT and RCM imaging are able to complement each other, the strengths of each helping overcome the limitations of the other. Four representative cases are summarized, out of the 15 investigated in a preliminary pilot study, demonstrating how OCT and RCM imaging may be synergistically combined to more accurately detect BCCs and more completely delineate margins. Our preliminary results highlight the potential benefits of combining the two technologies within a single probe to potentially guide diagnosis as well as treatment of BCCs.

  20. Reflectance confocal microscopy for monitoring the density of Demodex mites in patients with rosacea before and after treatment.

    Science.gov (United States)

    Sattler, E C; Hoffmann, V S; Ruzicka, T; Braunmühl, T V; Berking, C

    2015-07-01

    Demodex mites seem to serve as a pathogenic trigger in many Demodex-associated diseases such as rosacea. In facial skin of patients with rosacea significantly higher numbers of Demodex mites have been shown compared with healthy controls. Reflectance confocal microscopy (RCM) allows the detection and quantification of Demodex mites in vivo noninvasively. It is hypothesized that a reduction of Demodex mites under rosacea therapy can be monitored by RCM. To use RCM to monitor the density of Demodex mites in patients with rosacea before and after treatment. In 25 patients with facial rosacea RCM was performed before and after therapy. Mosaics of 5 × 5 mm(2) and 8 × 8 mm(2) were scanned, and the total numbers of mites per follicle and per area were counted, along with the number of follicles per area. In all patients Demodex folliculorum could be detected and quantified using RCM. RCM showed significant differences pre- and post-treatment (P = 0.0053 for 5 × 5 mm(2) and P rosacea under therapy, correlating to clinical improvement, can be quantified and monitored noninvasively. Possible reasons for this therapeutic effect are discussed. © 2015 British Association of Dermatologists.

  1. Non-invasive diagnosis of pink basal cell carcinoma: how much can we rely on dermoscopy and reflectance confocal microscopy?

    Science.gov (United States)

    Witkowski, A M; Łudzik, J; DeCarvalho, N; Ciardo, S; Longo, C; DiNardo, A; Pellacani, G

    2016-05-01

    Non-pigmented 'pink' cutaneous lesions in differential diagnosis with basal cell carcinoma may present a challenge for clinicians. Our objective was to determine the potential improvement of diagnostic accuracy using combined dermoscopy-reflectance confocal microscopy (RCM) image evaluation. Two hundred and sixty clinically equivocal 'pink' cutaneous lesions were evaluated retrospectively. Reader accuracy was tested with dermoscopy images only vs. RCM and combined dermoscopy-RCM images. Out of 260 equivocal 'pink' cutaneous lesions, there were 114 basal cell carcinomas within a total of 140 malignancies that included 12 melanomas, 13 squamous cell carcinomas, and 1 other malignancy type. Dermoscopy only evaluation resulted in an overall sensitivity of 85.1% and specificity of 92.4%, resulting in a positive predictive value (PPV) of 89.8%, with 1 of 12 melanomas misdiagnosed. RCM evaluation resulted in an overall sensitivity of 85.1% and specificity of 93.8%, resulting in a PPV of 91.5%, with no melanomas misdiagnosed. Combined dermoscopy-RCM evaluation resulted in an overall sensitivity of 77.2% and specificity of 96.6%, resulting in a PPV of 94.6%. The combination of dermoscopy-RCM evaluation significantly improves the accuracy and safety threshold in equivocal 'pink' cutaneous lesions in the differential diagnosis of basal cell carcinoma. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. International Trade and Sustainable Development: Reflections on the Regulation Through the International Organizations

    Directory of Open Access Journals (Sweden)

    Eugênia Cristina Nilsen Ribeiro Barza

    2016-12-01

    Full Text Available The purpose of this study is to analyze the link between international trade and development. The regulation of international trade by international organizations will be explored. In the post-WTO scenario, there is the formation of a new governance in relation to international trade, with a tendency to appreciation of international relations at the Westphalian style. This phenomenon is worrying , especially in light of Agenda 2030 for Sustainable Development and the 17 Sustainable Development Goals established by the UN, which require a multilateral regulation of trade and participation of international organizations , particularly the WTO , for implementation their goals.

  3. The value of in vivo reflectance confocal microscopy in the diagnosis and monitoring of inflammatory and infectious skin diseases: a systematic review

    NARCIS (Netherlands)

    Hoogedoorn, L.; Peppelman, M.; Kerkhof, P.C.M. van de; Erp, P.E.J. van; Gerritsen, M.J.P.

    2015-01-01

    In vivo examination of the skin by reflectance confocal microscopy (RCM) has been performed for about 20 years, leading to a broad spectrum of imaged infectious and inflammatory skin diseases (ISD) with many described RCM features. We systematically reviewed all available literature concerning ISD

  4. The current role of in vivo reflectance confocal microscopy within the continuum of actinic keratosis and squamous cell carcinoma: a systematic review

    NARCIS (Netherlands)

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

    2016-01-01

    BACKGROUND: Clinical differentiation between actinic keratosis (AK), squamous cell carcinoma (SCC) in situ, and invasive SCC and its variants may be difficult. Reflectance confocal microscopy (RCM) is a non-invasive technique for in vivo skin imaging. OBJECTIVES: To explicate the diagnostic and

  5. In vivo Reflectance Confocal Microscopy: A Useful Tool to Select the Location of a Punch Biopsy in a Large, Clinically Indistinctive Lesion

    Directory of Open Access Journals (Sweden)

    Malou Peppelman

    2013-04-01

    Full Text Available Reflectance confocal microscopy (RCM is a noninvasive technique for in vivo imaging of the skin that allows evaluation of the total lesion area. This case report about a 66-year-old patient with a clinically indistinctive, previously treated erythematous lesion on the frontal part of the face demonstrates the use of RCM to select the proper biopsy location.

  6. A study of internal oxidation in carburized steels by glow discharge optical emission spectroscopy and scanning electron microscopy

    CERN Document Server

    An, X; Rainforth, W M; Chen, L

    2003-01-01

    The internal oxidation of Cr-Mn carburizing steel was studied. Internal oxidation was induced using a commercial carburizing process. Sputter erosion coupled with glow discharge optical emission spectroscopy (GDOES) was used to determine the depth profile elemental distribution within the internal oxidation layer (<10 mu m). In addition, scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS) studies were carried out on selected sputter eroded surfaces. Oxide type was identified primarily by transmission electron microscopy (TEM). The carburized surface was found to consist of a continuous oxide layer, followed by a complex internal oxidation layer, where Cr and Mn oxides were found to populate grain boundaries in a globular form in the near surface region. At greater depths (5-10 mu m), Si oxides formed as a grain boundary network. The internal oxides (mainly complex oxides) grew quickly during the initial stages of the carburizing process (2 h, 800 deg. C+3 h, 930 deg. C). G...

  7. PREFACE: 11th International Conference on X-ray Microscopy (XRM2012)

    Science.gov (United States)

    Xu, Hongjie; Wu, Ziyu; Tai, Renzhong

    2013-10-01

    The Eleventh International Conference on X-ray Microscopy (XRM2012) was held on 5-10 August 2012 at the Hope hotel in Shanghai. Historically, for the first time the XRM conference took place in China. The conference was jointly hosted by the Shanghai Synchrotron Radiation Facility (SSRF) and the National Synchrotron Radiation Laboratory (NSRL). The series of XRM conferences dates back to 1983 in Göttingen, Germany. Since the Zürich conference, XRM2008, it has been held every two years, showing its increasing popularity among the x-ray microscopy communities around the world. Research in the area of x-ray microscopy is advancing very fast with the development of synchrotron radiation techniques, especially the emergence of third generation light sources with low natural emittance which has significantly pushed forward the development of technologies and applications in this area. This has been fully demonstrated in presentations from this and previous XRM conferences. XRM2012 was attended by 295 people including 21 invited speakers, 53 contributing speakers, 55 students, and 13 industry exhibitors. Over 232 abstracts were submitted for oral or poster presentation and 56 original, peer-reviewed papers are published in these proceedings. The conference was sponsored by the Chinese Academy of Sciences (CAS) and the National Natural Science Foundation of China (11210301016/A0802), and three gold sponsors active in industrial and technological fields related to x-ray microscopy. An exhibition booth was offered free to Australia synchrotron, the host for XRM2014, to promote the next conference which will be held in Melbourne, Australia in 2014. An unforgettable memory for most conference participants might be the charming night cruise along Pujiang river which was part of the welcome reception on the first evening. The Werner Meyer-Ilse Award (WMIA) prize this year was awarded to Irene Zanette (TU-München) and Stephan Werner (HZB-Berlin), the former for her pioneering

  8. An unsupervised machine learning method for delineating stratum corneum in reflectance confocal microscopy stacks of human skin in vivo

    Science.gov (United States)

    Bozkurt, Alican; Kose, Kivanc; Fox, Christi A.; Dy, Jennifer; Brooks, Dana H.; Rajadhyaksha, Milind

    2016-02-01

    Study of the stratum corneum (SC) in human skin is important for research in barrier structure and function, drug delivery, and water permeability of skin. The optical sectioning and high resolution of reflectance confocal microscopy (RCM) allows visual examination of SC non-invasively. Here, we present an unsupervised segmentation algorithm that can automatically delineate thickness of the SC in RCM images of human skin in-vivo. We mimic clinicians visual process by applying complex wavelet transform over non-overlapping local regions of size 16 x 16 μm called tiles, and analyze the textural changes in between consecutive tiles in axial (depth) direction. We use dual-tree complex wavelet transform to represent textural structures in each tile. This transform is almost shift-invariant, and directionally selective, which makes it highly efficient in texture representation. Using DT-CWT, we decompose each tile into 6 directional sub-bands with orientations in +/-15, 45, and 75 degrees and a low-pass band, which is the decimated version of the input. We apply 3 scales of decomposition by recursively transforming the low-pass bands and obtain 18 bands of different directionality at different scales. We then calculate mean and variance of each band resulting in a feature vector of 36 entries. Feature vectors obtained for each stack of tiles in axial direction are then clustered using spectral clustering in order to detect the textural changes in depth direction. Testing on a set of 15 RCM stacks produced a mean error of 5.45+/-1.32 μm, compared to the "ground truth" segmentation provided by a clinical expert reader.

  9. Video-mosaicking of in vivo reflectance confocal microscopy images for noninvasive examination of skin lesion (Conference Presentation)

    Science.gov (United States)

    Kose, Kivanc; Gou, Mengran; Yelamos, Oriol; Cordova, Miguel A.; Rossi, Anthony; Nehal, Kishwer S.; Camps, Octavia I.; Dy, Jennifer G.; Brooks, Dana H.; Rajadhyaksha, Milind

    2017-02-01

    In this report we describe a computer vision based pipeline to convert in-vivo reflectance confocal microscopy (RCM) videos collected with a handheld system into large field of view (FOV) mosaics. For many applications such as imaging of hard to access lesions, intraoperative assessment of MOHS margins, or delineation of lesion margins beyond clinical borders, raster scan based mosaicing techniques have clinically significant limitations. In such cases, clinicians often capture RCM videos by freely moving a handheld microscope over the area of interest, but the resulting videos lose large-scale spatial relationships. Videomosaicking is a standard computational imaging technique to register, and stitch together consecutive frames of videos into large FOV high resolution mosaics. However, mosaicing RCM videos collected in-vivo has unique challenges: (i) tissue may deform or warp due to physical contact with the microscope objective lens, (ii) discontinuities or "jumps" between consecutive images and motion blur artifacts may occur, due to manual operation of the microscope, and (iii) optical sectioning and resolution may vary between consecutive images due to scattering and aberrations induced by changes in imaging depth and tissue morphology. We addressed these challenges by adapting or developing new algorithmic methods for videomosaicking, specifically by modeling non-rigid deformations, followed by automatically detecting discontinuities (cut locations) and, finally, applying a data-driven image stitching approach that fully preserves resolution and tissue morphologic detail without imposing arbitrary pre-defined boundaries. We will present example mosaics obtained by clinical imaging of both melanoma and non-melanoma skin cancers. The ability to combine freehand mosaicing for handheld microscopes with preserved cellular resolution will have high impact application in diverse clinical settings, including low-resource healthcare systems.

  10. Tumor regrowth and development of keratinocytic neoplasms in patients under smoothened inhibition: in vivo assessment with reflectance confocal microscopy.

    Science.gov (United States)

    Alarcon, I; Pasquali, P; Malvehy, J; Puig, S

    2017-08-01

    The regrowth of a tumor after complete clinical response and the development of keratinocytic neoplasms while patients are still undergoing continuous vismodegib have stressed the importance of the accurate monitoring to detect recurrences earlier and ensure the best possible outcome. The objective of this study was to determine the role of reflectance confocal microscopy (RCM) in monitoring the response of locally advanced basal cell carcinoma (laBCC) to vismodegib and to discard secondary resistance. Seven patients presenting with nine laBCC, were prospectively included and their response to this drug was assessed by means of clinical examination, dermoscopy, and RCM. The study was conducted at the Melanoma Unit in Hospital Clinic of Barcelona, between June 2012 and March 2013. Histologically confirmed lesion 10 mm or larger in diameter for which surgery was contraindicated and radiation therapy was inappropriate. The median patient age was 73 years and the most common histological type was infiltrating BCC. RCM allowed the identification of residual tumor in two lesions and to confirm complete response in the other four cases. Two patients developed new lesions within the tumor bed, they were assessed by RCM showing features of actinic keratosis which were confirmed by histopathology. The use of in vivo RCM allowed the characterization of the dynamic morphologic changes in tumor response helping to better define partial response and to differentiate it from secondary resistance. Another interesting observation was the recognition of a phenomenon characterized by the development of keratinocytic neoplasms within the tumor bed. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Total internal reflection resonance light scattering at solid/liquid interfaces.

    Science.gov (United States)

    Tang, Yao-Ji; Chen, Ying; Yao, Min-Na; Li, Yao-Qun

    2008-08-05

    Total internal reflection (TIR) technique is an interface-specific tool and resonance light scattering (RLS) is of high sensitivity. The combination of both approaches is introduced into the solid/liquid interface for the first time. The behaviors of mixture of TPPS and BSA at the interface have been studied with total internal reflection resonance light scattering (TIR-RLS). The preliminary experimental results indicate that TIR-RLS is a good approach to study the interaction and distinguish the states of macromolecules at the solid/liquid interface.

  12. Israeli medical education: international perspectives, and reflections on challenges and changes.

    Science.gov (United States)

    Katz, David R

    2016-01-01

    Medical education is a dynamic and continually evolving process, some of which is style, and some of which is linked to changing perspectives in medical practice. A paper by Reis et al., taken in conjunction with the recent paper from an ad hoc International Review Committee (Schoenbaum et al.), provides a reflective view of where Israeli medical education stood in 2014 and places it in an international perspective. Reis at al also take this further, showing that in Israel change is occurring as a result of this review and comment on a number of important issues where further reflection, discussion, and work is required.

  13. Slow-light total-internal-reflection switch with bending angle of 30 deg.

    Science.gov (United States)

    Fuchida, Ayumi; Matsutani, Akihiro; Koyama, Fumio

    2011-07-15

    Slowing light in a Bragg reflector waveguide is used to miniaturize optical waveguide switches. We can realize a giant equivalent refractive index change induced by carrier injection near a cutoff wavelength due to its large waveguide dispersion. We fabricate and characterize a reflection-type slow-light switch. Input light is reflected at the off state due to an equivalent index difference between an oxide aperture and an oxide region, while it passes through at the on state, since the equivalent index difference is compensated using carrier injection. We obtained a large bending angle of 30° with total internal reflection of slow light. © 2011 Optical Society of America

  14. PREFACE: 17th International Conference on Microscopy of Semiconducting Materials 2011

    Science.gov (United States)

    Walther, T.; Midgley, P. A.

    2011-11-01

    This volume contains invited and contributed papers from the 17th international conference on 'Microscopy of Semiconducting Materials' held at Churchill College, University of Cambridge, on 4-7 April 2011. The meeting was organised under the auspices of the Institute of Physics and supported by the Royal Microscopical Society as well as the Materials Research Society of the USA. This conference series deals with recent advances in semiconductor studies carried out by all forms of microscopy, with an emphasis on electron microscopy and related techniques with high spatial resolution. This time the meeting was attended by 131 delegates from 25 countries world-wide, a record in terms of internationality. As semiconductor devices shrink further new routes of device processing and characterisation need to be developed, and, for the latter, methods that offer sub-nanometre spatial resolution are particularly valuable. The various forms of imaging, diffraction and spectroscopy available in modern microscopes are powerful tools for studying the microstructure, the electronic structure, the chemistry and also electric fields in semiconducting materials. Recent advances in instrumentation, from lens aberration correction in both TEM and STEM instruments, to the development of a wide range of scanning probe techniques, as well as new methods of signal quantification have been presented at this conference. Two examples of topics at this meeting that have attracted a number of interesting studies were: the correlation of microstructural, optical and chemical information at atomic resolution with nanometre-scale resolved maps of the local electrical fields in (In,Al)GaN based semiconductors and tomographic approaches to characterise ensembles of nanowires and stacks of processed layers in devices Figure 1 Figure 1. Opening lecture by Professor Sir Colin J Humphreys. Each manuscript submitted for publication in this proceedings volume has been independently reviewed and revised

  15. Microscopy, culture, and quantitative real-time PCR examination confirm internalization of mycobacteria in plants.

    Science.gov (United States)

    Kaevska, M; Lvoncik, S; Slana, I; Kulich, P; Kralik, P

    2014-07-01

    The environment is a reservoir of nontuberculous mycobacteria and is considered a source of infection for animals and humans. Mycobacteria can persist in different types of environments for a relatively long time. We have studied their possible internalization into plant tissue through intact, as well as damaged, root systems of different types of plants grown in vitro and under field conditions. The substrate into which plants were seeded was previously contaminated with different strains of Mycobacterium avium (10(8) to 10(10) cells/g of soil) and feces from animals with paratuberculosis. We detected M. avium subsp. avium, hominissuis, and paratuberculosis in the stems and leaves of the plants by both culture and real-time quantitative PCR. The presence of mycobacteria in the plant tissues was confirmed by microscopy. The concentration of mycobacteria found inside plant tissue was several orders of magnitude lower (up to 10(4) cells/g of tissue) than the initial concentration of mycobacteria present in the culture medium or substrate. These findings led us to the hypothesis that plants may play a role in the spread and transmission of mycobacteria to other organisms in the environment. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  16. Celebrating international collaboration: reflections on the first Virtual International Practice Development Conference

    Directory of Open Access Journals (Sweden)

    Moira Stephens

    2016-11-01

    Full Text Available This article reports on the first Virtual International Practice Development Conference, held in May 2015 to celebrate International Nurses Day. The article describes key aspects of its planning, offers a flavour of the event itself and sets out an evaluation, including learning points and recommendations to assist with planning similar events in the future. Central to our learning are: The need for practice developers to grasp skills in technology associated with virtual space The need to embrace virtual space itself as another means by which creative and communicative spaces can be established for active learning and practice development activities The potential advantages that international virtual engagement has over face-to-face national or international engagement The delivery of this virtual event made a significant international contribution to global practice development activity within the International Practice Development Collaborative and to enabling practice developers to connect and celebrate on a more global basis. Implications for practice: Virtual space technology skills can assist with sharing and translating practice development research, innovations and critical commentary Virtual space can provide an adjunct to creative and communicative learning spaces Global networking opportunities can be developed and enhanced through the use of virtual space technology Practice developers need to role model the use of virtual technologies

  17. A pilot study using reflectance confocal microscopy (RCM) in the assessment of a novel formulation for the treatment of melasma.

    Science.gov (United States)

    Tsilika, Katerina; Levy, Jean Luc; Kang, Hee Young; Duteil, Luc; Khemis, Abdallah; Hughes, Rosalind; Passeron, Thierry; Ortonne, Jean Paul; Bahadoran, Philippe

    2011-11-01

    Melasma is a common pigmentary disorder caused by abnormal melanin deposits within the skin. Hydroquinone (HQ) is presently the most popular depigmenting agent, however the treatment of melasma remains unsatisfactory, resulting in a need to evaluate new depigmenting agents. The objective of this study was to assess, using standard methods and a novel technique, in vivo Reflectance Confocal Microscopy (RCM), the efficacy and safety of a new non-HQ bleaching agent Dermamelan® (Mesoestetic, Barcelona, Spain) in the treatment of melasma. Ten women with melasma were enrolled in an open-label trial lasting four months. Patients were of Fitzpatrick skin types II-IV. A non-HQ depigmenting agent (Dermamelan) was applied once-daily for three months. Melasma Area and Severity Indices (MASI) were measured. Standard and UV-light photographs were taken and in vivo RCM, which detects pigmentary changes at a cellular level, was done. Evaluations were performed before treatment, on the first, second and third month of treatment and one month after treatment. Upon cessation of the trial, patients completed a questionnaire regarding efficacy and tolerance. At baseline, RCM detected hyperpigmented keratinocytes in all patients, dendritic cells in 2/10 patients, and melanophages in 2/10 patients. Based on the MASI score, Dermamelan treatment improved melasma by 50 percent. This was confirmed by standard and UV-light photography. Maximum therapeutic effect was usually reached by one month of treatment and was maintained at one month following its completion. Interestingly Dermamelan treatment also induced a statistically significant decrease of pigmented epidermal keratinocytes as detected by RCM. Patients with melanophages on RCM at baseline had a poorer outcome, but not those with dendritic cells. Mild irritation was the only adverse event observed during treatment. The majority of patients were satisfied with the result. This study suggests that Dermamelan produces significant rapid

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

    Science.gov (United States)

    Banzhaf, Christina A; Wind, Bas S; Mogensen, Mette; Meesters, Arne A; Paasch, Uwe; Wolkerstorfer, Albert; Haedersdal, Merete

    2016-02-01

    Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) offer high-resolution optical imaging of the skin, which may provide benefit in the context of laser-assisted drug delivery. We aimed to characterize postoperative healing of ablative fractional laser (AFXL)-induced channels and dynamics in their spatiotemporal closure using in vivo OCT and RCM techniques. The inner forearm of healthy subjects (n = 6) was exposed to 10,600 nm fractional CO2 laser using 5 and 25% densities, 120 μm beam diameter, 5, 15, and 25 mJ/microbeam. Treatment sites were scanned with OCT to evaluate closure of AFXL-channels and RCM to evaluate subsequent re-epithelialization. OCT and RCM identified laser channels in epidermis and upper dermis as black, ablated tissue defects surrounded by characteristic hyper-and hyporeflective zones. OCT imaged individual laser channels of the entire laser grid, and RCM imaged epidermal cellular and structural changes around a single laser channel to the depth of the dermoepidermal junction (DEJ) and upper papillary dermis. OCT images visualized a heterogeneous material in the lower part of open laser channels, indicating tissue fluid. By OCT the median percentage of open channels was evaluated at several time points within the first 24 hours and laser channels were found to gradually close, depending on the used energy level. Thus, at 5 mJ/microbeam, 87% (range 73-100%) of channels were open one hour after laser exposure, which declined to 27% (range 20-100%) and 20% (range 7-93%) at 12 and 24 hours after laser exposure, respectively. At 25 mJ/microbeam, 100% (range 100-100%) of channels were open 1 hour after laser exposure while 53% (range 33-100%) and 40% (range 0-100%) remained open at 12 and 24 hours after exposure. Median depth and width of open channels decreased over time depending of applied energy. RCM verified initial re-epithelialization from day 2 for all energy levels used. Morphology of ablation defects by OCT and

  19. Creating Comic Books in Nigeria: International Reflections on Literacy, Creativity, and Student Engagement

    Science.gov (United States)

    Bitz, Michael; Emejulu, Obiajulu

    2016-01-01

    This article is an international reflection on literacy, creativity, and student engagement. The authors collaborated to help Nigerian youths and their teachers develop, design, and share original comic books. By leveraging student engagement for literacy learning, the authors highlighted the crucial role of creativity in the classroom. The…

  20. Measurement of the Longitudinal Shift of Radiation at Total Internal Reflection by Microwave Techniques

    Science.gov (United States)

    Akylas, Victor; And Others

    1976-01-01

    Describes a method to experimentally determine the longitudinal shift of a microwave beam at total internal reflection. Suggests that the activity be incorporated into an undergraduate laboratory program due to its ease in set-up and clarity of results. (CP)

  1. Four Members of the International Adult and Continuing Education Hall of Fame Reflect on Their Careers

    Science.gov (United States)

    Sandmann, Lorilee R.; Miller, Gary E.

    2011-01-01

    Drawing on collective experience of over 200 years, four members of the International Adult and Continuing Education Hall of Fame were panelists in a session at the 2010 National Outreach Scholarship Conference. As the panelists reflected on careers in the field of adult and continuing education, four sustaining themes emerged: commitment,…

  2. Symbolic Uses of Evaluation in the International Aid Sector: Arguments for Critical Reflection

    Science.gov (United States)

    McNulty, James

    2012-01-01

    Significant progress has been made in recent years to improve the quality of the evaluation of international aid. Increasingly, this includes an interest in improving the way evaluations are used to improve policies and programmes. However, the prevalence of symbolic use--a phenomenon that is often mentioned but rarely studied--reflects an…

  3. Reflections

    Indian Academy of Sciences (India)

    pumped' by displacement of the center of gravity of the person sitting or standing on it. Back in Europe (1925). In the fall of 1925 I read in some journal that an International Congress on Mechanics was to be held in. Zurichthe following autumn.

  4. Reflections

    Directory of Open Access Journals (Sweden)

    Joanne Embree

    2001-01-01

    Full Text Available Ideally, editorials are written one to two months before publication in the Journal. It was my turn to write this one. I had planned to write the first draft the evening after my clinic on Tuesday, September 11. It didn't get done that night or during the next week. Somehow, the topic that I had originally chosen just didn't seem that important anymore as I, along my friends and colleagues, reflected on the changes that the events of that day were likely to have on our lives.

  5. Attenuated total internal reflection infrared microspectroscopic imaging using a large-radius germanium internal reflection element and a linear array detector.

    Science.gov (United States)

    Patterson, Brian M; Havrilla, George J

    2006-11-01

    The number of techniques and instruments available for Fourier transform infrared (FT-IR) microspectroscopic imaging has grown significantly over the past few years. Attenuated total internal reflectance (ATR) FT-IR microspectroscopy reduces sample preparation time and has simplified the analysis of many difficult samples. FT-IR imaging has become a powerful analytical tool using either a focal plane array or a linear array detector, especially when coupled with a chemometric analysis package. The field of view of the ATR-IR microspectroscopic imaging area can be greatly increased from 300 x 300 microm to 2500 x 2500 microm using a larger internal reflection element of 12.5 mm radius instead of the typical 1.5 mm radius. This gives an area increase of 70x before aberrant effects become too great. Parameters evaluated include the change in penetration depth as a function of beam displacement, measurements of the active area, magnification factor, and change in spatial resolution over the imaging area. Drawbacks such as large file size will also be discussed. This technique has been successfully applied to the FT-IR imaging of polydimethylsiloxane foam cross-sections, latent human fingerprints, and a model inorganic mixture, which demonstrates the usefulness of the method for pharmaceuticals.

  6. Trapping of microwave radiation in hollow polypyrrole microsphere through enhanced internal reflection: A novel approach

    Science.gov (United States)

    Panigrahi, Ritwik; Srivastava, Suneel K.

    2015-01-01

    In present work, spherical core (polystyrene, PS)/shell (polypyrrole, PPy) has been synthesized via in situ chemical oxidative copolymerization of pyrrole (Py) on the surface of sulfonated PS microsphere followed by the formation of hollow polypyrrole (HPPy) shell by dissolving PS inner core in THF. Thereafter, we first time established that such fabricated novel art of morphology acts as a conducting trap in absorbing electromagnetic (EM) wave by internal reflection. Further studies have been extended on the formation of its silver nanocomposites HPPy/Ag to strengthen our contention on this novel approach. Our investigations showed that electromagnetic interference (EMI) shielding efficiency (SE) of HPPy (34.5-6 dB) is significantly higher compared to PPy (20-5 dB) in the frequency range of 0.5-8 GHz due to the trapping of EM wave by internal reflection. We also observed that EMI shielding is further enhanced to 59-23 in 10 wt% Ag loaded HPPy/Ag-10. This is attributed to the simultaneous contribution of internal reflection as well as reflection from outer surface. Such high EMI shielding capacity using conducting polymers are rarely reported.

  7. International education and reflection: transition of Swedish and American nursing students to authenticity.

    Science.gov (United States)

    Lepp, Margret; Zorn, CeCelia R; Duffy, Patricia R; Dickson, Rana J

    2003-01-01

    Reflection, a process grounded in distancing from the self to enhance self-awareness, can be used as a pedagogic activity to promote students' transition to a greater authenticity and professionalism and, therefore, improve patient care and nursing practice. In this international educational project (implemented in 2001) using interactive videoconferencing technology (IVC), Swedish and U.S. nursing students and faculty incorporated reflective journaling, drama in education, photolanguage, and off-air meeting discussions to enhance personal and professional development. Highlights from the literature, a description of the project, and student and faculty appraisals are presented.

  8. Total Internal Reflection Accounts for the Bright Color of the Saharan Silver Ant

    Science.gov (United States)

    Aron, Serge

    2016-01-01

    The Saharan silver ant Cataglyphis bombycina is one of the terrestrial living organisms best adapted to tolerate high temperatures. It has recently been shown that the hairs covering the ant’s dorsal body part are responsible for its silvery appearance. The hairs have a triangular cross-section with two corrugated surfaces allowing a high optical reflection in the visible and near-infrared (NIR) range of the spectrum while maximizing heat emissivity in the mid-infrared (MIR). Those two effects account for remarkable thermoregulatory properties, enabling the ant to maintain a lower thermal steady state and to cope with the high temperature of its natural habitat. In this paper, we further investigate how geometrical optical and high reflection properties account for the bright silver color of C. bombycina. Using optical ray-tracing models and attenuated total reflection (ATR) experiments, we show that, for a large range of incidence angles, total internal reflection (TIR) conditions are satisfied on the basal face of each hair for light entering and exiting through its upper faces. The reflection properties of the hairs are further enhanced by the presence of the corrugated surface, giving them an almost total specular reflectance for most incidence angles. We also show that hairs provide an almost 10-fold increase in light reflection, and we confirm experimentally that they are responsible for a lower internal body temperature under incident sunlight. Overall, this study improves our understanding of the optical mechanisms responsible for the silver color of C. bombycina and the remarkable thermoregulatory properties of the hair coat covering the ant’s body. PMID:27073923

  9. Raman and fluorescence microscopy to study the internalization and dissolution of photosensitizer nanoparticles into living cells

    Science.gov (United States)

    Scalfi-Happ, Claudia; Steiner, Rudolf; Wittig, Rainer; Graefe, Susanna; Ryabova, Anastasia; Loschenov, Victor

    2015-07-01

    In this present study we applied Raman and fluorescence microscopy to investigate the internalisation, cellular distribution and effects on cell metabolism of photosensitizer nanoparticles for photodynamic therapy in fibroblasts and macrophages.

  10. Depth enhancement of multi-layer light field display using polarization dependent internal reflection.

    Science.gov (United States)

    Jo, Na-Young; Lim, Hong-Gi; Lee, Sung-Keun; Kim, Yong-Soo; Park, Jae-Hyeung

    2013-12-02

    A technique to enhance the depth range of the multi-layer light field three-dimensional display is proposed. A set of the optical plates are stacked in front of the conventional multi-layer light field display, creating additional internal reflection for one polarization state. By switching between two orthogonal polarization states in synchronization with the displayed three-dimensional images, the depth range of the display can be doubled. The proposed method is verified experimentally, confirming its feasibility.

  11. Trapping of microwave radiation in hollow polypyrrole microsphere through enhanced internal reflection: A novel approach

    OpenAIRE

    Ritwik Panigrahi; Suneel K. Srivastava

    2015-01-01

    In present work, spherical core (polystyrene, PS)/shell (polypyrrole, PPy) has been synthesized via in situ chemical oxidative copolymerization of pyrrole (Py) on the surface of sulfonated PS microsphere followed by the formation of hollow polypyrrole (HPPy) shell by dissolving PS inner core in THF. Thereafter, we first time established that such fabricated novel art of morphology acts as a conducting trap in absorbing electromagnetic (EM) wave by internal reflection. Further studies have bee...

  12. Specific Features of Reflection of Information Regarding Lease Operations in the National and International Standards

    Directory of Open Access Journals (Sweden)

    Nikolenko Nataliya V.

    2013-12-01

    Full Text Available The article identifies the degree of correspondence of the national Provisions (Standard of Business Accounting (PSBA Lease with the international standard and provides recommendations with respect to their closing up. On the results of the study the author provides specific features of international and national standards – the existing IFRS 17 Lease and national PSBA 14 Lease by the following components: definition of lease, its classification and reflection in accounting. Also the text of PSBA 31 Financial Expenditures is supplemented with provisions on capitalisation of financial expenditures prospectively, which would allow avoidance of correction of the balance of the retained income and provision of comparative information for previous periods. The article provides an algorithm of division of lease for accounting purposes on the basis of international standards. Its use would ensure correctness of reflection of lease operations in accounting and would serve as a basis for development of methodical provisions with respect to accounting. By the result of the study the author forms definition of the qualification asset as an asset which requires considerable time for its creation, preparation for target use, sales or acquisition of the ownership right. Capitalisation of such expenditures would allow non-reduction of the accounting income and also would provide a possibility to reflect financial expenditures in accordance with their economic essence.

  13. A study of internal oxidation in carburized steels by glow discharge optical emission spectroscopy and scanning electron microscopy

    International Nuclear Information System (INIS)

    An, X; Cawley, J.; Rainforth, W.M.; Chen, L.

    2003-01-01

    The internal oxidation of Cr-Mn carburizing steel was studied. Internal oxidation was induced using a commercial carburizing process. Sputter erosion coupled with glow discharge optical emission spectroscopy (GDOES) was used to determine the depth profile elemental distribution within the internal oxidation layer (<10 μm). In addition, scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS) studies were carried out on selected sputter eroded surfaces. Oxide type was identified primarily by transmission electron microscopy (TEM). The carburized surface was found to consist of a continuous oxide layer, followed by a complex internal oxidation layer, where Cr and Mn oxides were found to populate grain boundaries in a globular form in the near surface region. At greater depths (5-10 μm), Si oxides formed as a grain boundary network. The internal oxides (mainly complex oxides) grew quickly during the initial stages of the carburizing process (2 h, 800 deg. C+3 h, 930 deg. C). GDOES proved to be an excellent tool for the quantification of oxidation and element distribution as a function of depth, particularly when combined with SEM and TEM to identify oxide type and morphology

  14. Beyond ‘Innocents Abroad’: Reflecting on Sustainability Issues During International Study Trips

    Directory of Open Access Journals (Sweden)

    Anne H. Reilly

    2016-12-01

    Full Text Available With ecosystems and populations in many regions threatened by rapid development, sustainability is a critical component for businesses in mature markets and emerging economies alike. The International Association of Jesuit Business Schools notes that global sustainability involves a broad set of interconnected issues ranging from environmental preservation to social justice to desirable production and consumption patterns. Jesuit business schools are uniquely positioned to address sustainability issues with their focus on teaching managerial content in tandem with corporate social responsibility. Further, the Ignatian Pedagogy Paradigm of experience, reflection, and action would suggest that business students may benefit from reflective observation in support of learning about sustainability. In this paper, we examine the international study trip as an opportunity for students to learn about sustainability, with results suggesting that student understanding about the broad sustainability domain may be enhanced through the study abroad experience. We discuss how two classes of primarily American MBA students traveling to emerging markets (one class to Santiago, Chile and one class to Johannesburg, South Africa were able to connect local business practices with economic and social as well as environmental sustainability issues, enhancing both student engagement and learning outcomes. Further, these students’ sustainability experiences while in an unfamiliar environment provided the opportunity to apply the potentially transformative experience, reflection, and action components of the Ignatian Pedagogy Paradigm. Compared to similar graduate business students enrolled in regular classes, we argue that these students discerned deeper connections with the economic, social, and environmental issues of sustainability.

  15. Internal-wave reflection from uniform slopes: higher harmonics and Coriolis effects

    Directory of Open Access Journals (Sweden)

    T. Gerkema

    2006-01-01

    Full Text Available Weakly nonlinear reflection of internal waves from uniform slopes produces higher harmonics and mean fields; the expressions are here derived for constant stratification and with Coriolis effects fully included, i.e. the horizontal component of the earth rotation vector (referred to as 'non-traditional'' is taken into account. Uniformity in one of the horizontal directions is assumed. It is shown that solutions can be as readily derived with as without ; hence there is no need to make the so-called Traditional Approximation. Examples of reflecting internal-wave beams are presented for super-inertial, inertial and sub-inertial frequencies. The problem of resonant and non-resonant forcing of the second harmonic is studied for single plane waves; unlike under the Traditional Approximation, the problem of reflection from a horizontal bottom no longer forms a singular case. Non-traditional effects are favourable to resonant forcing at near-tidal rather than near-inertial frequencies, and generally increase the intensity of the second harmonic. Strong stratification tends to suppress non-traditional effects, but a near-total suppression is only attained for high values of stratification that are characteristic of the seasonal thermocline; in most parts of the ocean, non-traditional effects can therefore be expected to be important.

  16. Chemical and structural composition study through transmission and reflection electron microscopy and X-ray microanalysis of damaged duramater cardiac valves

    International Nuclear Information System (INIS)

    Verginelli, G.; Didio, L.J.A.; Puig, L.B.; Allen, D.J.; Highinson, G.H.; Zerbini, E.J.

    1982-01-01

    Ten malfunctioning durameter aortic prosthesis, excised surgically after 44 to 54 months of implantation were studied through transmission and reflection electron microscopy and X-ray microanalysis. Duramater extracted at necropsy but not used for valve prosthesis and duramater aortic prosthesis not implanted in patients were used as controls. It was concluded that homologous duramater valves present subcellular changes following implantation, with degenerating and proliferating areas which could correspond either to normal adaptation or consequence of degeneration - rebuilding which begins with implantation; it is also emphazised the need for ultramicroscopic studies in evaluating biological tissues and establishing its applicability in cardiac surgery. (M.A.C.) [pt

  17. Design rule of nanostructures in light-emitting diodes for complete elimination of total internal reflection.

    Science.gov (United States)

    Son, Jun Ho; Kim, Jong Uk; Song, Yang Hee; Kim, Buem Joon; Ryu, Chul Jong; Lee, Jong-Lam

    2012-05-02

    Cone-shaped nanostructures with controllable side-wall angle are success- fully fabricated with a SiO(2) nanosphere lithography (NSL) etching mask. Vertical LEDs with cone-shaped nanostructures with a 24.1° side-wall angle provide 6% more light output power compared to those using hexagonal pyramids formed by photochemical etching. This achievement is attributed to effective elimination of total internal reflection by angle-controlled nanostructures. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Innovative light collimator with afocal lens and total internal reflection lens for daylighting system.

    Science.gov (United States)

    Chen, Bo-Jian; Chen, Yin-Ti; Ullah, Irfan; Chou, Chun-Han; Chan, Kai-Cyuan; Lai, Yi-Lung; Lin, Chia-Ming; Chang, Cheng-Ming; Whang, Allen Jong-Woei

    2015-10-01

    This research presents a novel design of the collimator, which uses total internal reflection (TIR), convex, and concave lenses for the natural light illumination system (NLIS). The concept of the NLIS is to illuminate building interiors with natural light, which saves energy consumption. The TIR lens is used to collimate the light, and convex and concave lenses are used to converge the light to the required area. The results have shown that the efficiency in terms of achieving collimated light using the proposed collimator at the output of the light collector is better than that of a previous system without a collimator.

  19. International peer review in undergraduate dentistry: enhancing reflective practice in an online community of practice.

    Science.gov (United States)

    Gardner, K; Bridges, S; Walmsley, D

    2012-11-01

    To stimulate and enhance student learning in the areas of global citizenship, critical reflection and e-learning, an online international peer review using a purpose-built web platform, has been developed between international dental schools. Since its inception in 2007, n = 6 dental schools from six different countries have participated with n = 384 dental students engaged in online peer review. Project development was conceptually analysed utilising Lave and Wenger's notion of a community of practice (CoP). Analysis drew on the three core components within the CoP organising framework: domain, community and practice. All three components were evident in building project identity. The domain focused on both curriculum and institutional co-operation. The community was evident for both educators and students. Finally, analysis of practice was found to be significant in terms of sustained interaction and collaboration. Empirical evaluation is recommended as the next phase of project design. © 2012 John Wiley & Sons A/S.

  20. Achromatic and high-resolution full-field X-ray microscopy based on total-reflection mirrors.

    Science.gov (United States)

    Matsuyama, Satoshi; Emi, Yoji; Kino, Hidetoshi; Kohmura, Yoshiki; Yabashi, Makina; Ishikawa, Tetsuya; Yamauchi, Kazuto

    2015-04-20

    We developed an achromatic and high-resolution full-field X-ray microscope based on advanced Kirkpatrick-Baez mirror optics that comprises two pairs of elliptical mirrors and hyperbolic mirrors utilizing the total reflection of X-rays. Performance tests to investigate the spatial resolution and chromatic aberration were performed at SPring-8. The microscope clearly resolved the pattern with ~100-nm feature size. Imaging the pattern by changing the X-ray energy revealed achromatism in the wide energy range of 8-11 keV.

  1. Liability for nuclear damage: an international perspective. Reflections on the revision of the Vienna Convention

    International Nuclear Information System (INIS)

    Lopuski, J.

    1993-01-01

    This book deals with deals of the complex issues of liability and compensation for nuclear damage which have been considered in the course of the work of the IAEA concerning the revision of the Vienna Convention on nuclear liability. It presents, in an orderly way, personal reflections of its author based on his experience gathered in years 1989-1992 when participating in this work. Necessarily it contains in some of its parts references to documents of the IAEA Standing Committee on Nuclear Liability; these documents because of their length could not be reproduced. Consequently these parts may not be fully intelligible for those who have not participated in or closely followed the Committee's work. The IAEA work on liability for nuclear damage was initiated in the wake of the impact made on the world's public opinion by the Chernobyl incident and its transboundary effects; issues of international state liability and full compensation have been raised. But humanitarian ideas have quickly been confronted with cold calculations of the cost of financial protection for victims and an open unwillingness of some nuclear states has been manifested. After three years of discussions no wide consensus could be reached on some basic issues, such as: relationship between international state and civil liability regimes, structure of international legislation, concept of nuclear damage, limits of compensation, role of public funds or jurisdiction. The author presents his approach to these controversial issue, trying to provide at the same time a theoretical outline for the future international legislation on nuclear liability. (author)

  2. Determination of continuous complex refractive index dispersion of biotissue based on internal reflection

    Science.gov (United States)

    Deng, Zhichao; Wang, Jin; Ye, Qing; Sun, Tengqian; Zhou, Wenyuan; Mei, Jianchun; Zhang, Chunping; Tian, Jianguo

    2016-01-01

    The complex refractive index dispersion (CRID), which contains the information on the refractive index dispersion and extinction coefficient spectra, is an important optical parameter of biotissue. However, it is hard to perform the CRID measurement on biotissues due to their high scattering property. Continuous CRID measurement based on internal reflection (CCRIDM-IR) is introduced. By using a lab-made apparatus, internal reflectance spectra of biotissue samples at multiple incident angles were detected, from which the continuous CRIDs were calculated based on the Fresnel formula. Results showed that in 400- to 750-nm range, hemoglobin solution has complicated dispersion and extinction coefficient spectra, while other biotissues have normal dispersion properties, and their extinction coefficients do not vary much with different wavelengths. The normal dispersion can be accurately described by several coefficients of dispersion equations (Cauchy equation, Cornu equation, and Conrady equation). To our knowledge, this is the first time that the continuous CRID of scattering biotissue over a continuous spectral region is measured, and we hereby have proven that CCRIDM-IR is a good method for continuous CRID research of biotissue.

  3. Light Microscopy Module: An On-Orbit Microscope Planned for the Fluids and Combustion Facility on the International Space Station

    Science.gov (United States)

    Doherty, Michael P.; Motil, Susan M.; Snead, John H.; Griffin, DeVon W.

    2001-01-01

    The Light Microscopy Module (LMM) is planned as a fully remotely controllable on-orbit microscope subrack facility, allowing flexible scheduling and control of fluids and biology experiments within NASA Glenn Research Center's Fluids and Combustion Facility on the International Space Station. Within the Fluids and Combustion Facility, four fluids physics experiments will utilize an instrument built around a light microscope. These experiments are the Constrained Vapor Bubble experiment (Peter C. Wayner of Rensselaer Polytechnic Institute), the Physics of Hard Spheres Experiment-2 (Paul M. Chaikin of Princeton University), the Physics of Colloids in Space-2 experiment (David A. Weitz of Harvard University), and the Low Volume Fraction Colloidal Assembly experiment (Arjun G. Yodh of the University of Pennsylvania). The first experiment investigates heat conductance in microgravity as a function of liquid volume and heat flow rate to determine, in detail, the transport process characteristics in a curved liquid film. The other three experiments investigate various complementary aspects of the nucleation, growth, structure, and properties of colloidal crystals in microgravity and the effects of micromanipulation upon their properties. Key diagnostic capabilities for meeting the science requirements of the four experiments include video microscopy to observe sample features including basic structures and dynamics, interferometry to measure vapor bubble thin film thickness, laser tweezers for colloidal particle manipulation and patterning, confocal microscopy to provide enhanced three-dimensional visualization of colloidal structures, and spectrophotometry to measure colloidal crystal photonic properties.

  4. Public Diplomacy and Refugee Relations Reflections of Turkey’s Refugees Relations on the International Media

    Directory of Open Access Journals (Sweden)

    Ergün Köksoy

    2015-11-01

    Full Text Available Public diplomacy is described as a new form of relations and communications between countries and societies in the field of international relations with the process of globalisation. The subject of refugees shown among the priority issues can be solved through international cooperation and solidarity with its results affecting all countries and societies, that’s why becoming part of public diplomacy. Asylum seekers and refugee rights are guaranteed by the Universal Declaration of Human Rights and considered to be an area that the international community needs to take the roles and share responsibilities. In this aspect, it is shown as global responsibilities and part of the humanitarian sensibility of countries and societies. In one hand, asylum seekers and refugees are considered to be the subject of the problem and crisis, on the other hand, due to contributing to the human and cultural interaction between the different communities, these are specified as part of public diplomacy. This article discusses the relationship between public diplomacy and refugees relations which provides the interaction between countries and effects the prestige and perception of them. In the study, to reveal the reflections of Turkey’s Refugees Relations on the International Media, three highest-circulation newspapers (“The Guardian”, “Le Monde”, “Der Spiegel” will be choosen from three important EU countries (United Kingdom, France, Germany. These newspapers’ headlines and news content which related to Turkey and Syrian refugees are going to be analized on three-month period. As a result, Turkish public diplomacy and refugee relations and its implications on the international media in the context of Syrian refugees will be evaluated and some recommendations for the future of Turkish public diplomacy and refugee relations will be provided.

  5. The International Criminal Court. reflections for a stress test on its foundations

    Directory of Open Access Journals (Sweden)

    Mateus Kowalski

    2011-01-01

    Full Text Available The constitution of the ICC in 2002 represents the ultimate example of the evolution of international criminal justice. The Court is referred to as a paradigmatic institution of the universalist concept of International Law, which envisages an enhanced international public order and which falls within the broader framework of the dominant liberal construct that currently characterizes both International Law and International Relations. However, the criticisms of universalism, in particular as regards the impositions of global liberal institutions and regulatory standards, are also reflected on the ICC. In particular, it has been met with several essential criticisms, such as its dependence on the Security Council, suggesting political interference in a criminal court, or the fact that until now only issues pertaining to Africa have been submitted to the Court, which in turn leads to suspicion about their selectivity. These are the criticisms that undermine the foundations of the ICC.At a time when the Court has not yet concluded any trial, and when there is still some scepticism about the success of its mission, knowing what to expect from the ICC in its task of crime preventing and retribution and building peace depends largely on the strength of its theoretical foundations. It is argued that despite the seemingly solid support discourse rooted in universalism, the answers advanced by this theory are not fully satisfactory due largely to the structural weaknesses that characterise it. This article seeks to offer food for thought on the subject and starts by gauging the competence of legal universalism to support “its” ICC with regard to these issues. It then identifies the aspects that can be addressed in within a more complex context, such as critical theory, which may contribute to the development of a discourse that grants the Court greater theoretical sustainability.

  6. Quantification of GPCR internalization by single-molecule microscopy in living cells.

    NARCIS (Netherlands)

    Serge, A.; Keijzer, S. de; Hemert, F. Van; Hickman, M.R.; Hereld, D.; Spaink, H.P.; Schmidt, T.; Snaar-Jagalska, B.E.

    2011-01-01

    Receptor internalization upon ligand stimulation is a key component of a cell's response and allows a cell to correctly sense its environment. Novel fluorescent methods have enabled the direct visualization of the agonist-stimulated G-protein-coupled receptors (GPCR) trafficking in living cells.

  7. PREFACE: NC-AFM 2005: Proceedings of the 8th International Conference on Non-Contact Atomic Force Microscopy

    Science.gov (United States)

    Reichling, M.; Mikosch, W.

    2006-04-01

    The 8th International Conference on Non-Contact Atomic Force Microscopy, held in Bad Essen, Germany, from 15 18th August 2005, attracted a record breaking number of participants presenting excellent contributions from a variety of scientific fields. This clearly demonstrated the high level of activity and innovation present in the community of NC-AFM researchers and the continuous growth of the field. The strongest ever participation of companies for a NC-AFM meeting is a sign for the emergence of new markets for the growing NC-AFM community; and the high standard of the products presented at the exhibition, many of them brand-new developments, reflected the unbroken progress in technology. The development of novel technologies and the sophistication of known techniques in research laboratories and their subsequent commercialization is still a major driving force for progress in this area of nanoscience. The conference was a perfect demonstration of how progress in the development of enabling technologies can readily be transcribed into basic research yielding fundamental insight with an impact across disciplines. The NC-AFM 2005 scientific programme was based on five cornerstones, each representing an area of vivid research and scientific progress. Atomic resolution imaging on oxide surfaces, which has long been a vision for the catalysis community, appears to be routine in several laboratories and after a period of demonstrative experiments NC-AFM now makes unique contributions to the understanding of processes in surface chemistry. These capabilities also open up new routes for the analysis of clusters and molecules deposited on dielectric surfaces where resolution limits are pushed towards the single atom level. Atomic precision manipulation with the dynamic AFM left the cradle of its infancy and flourishes in the family of bottom-up fabrication nanotechnologies. The systematic development of established and the introduction of new concepts of contrast

  8. Introduction to the IEEE International Symposium on Applications of Ferroelectrics and International Symposium on Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials.

    Science.gov (United States)

    Ye, Zuo-Guang; Tan, Xiaoli; Bokov, Alexei A

    2012-09-01

    The 20th IEEE International Symposium on Applications of Ferroelectrics (ISAF) was held on July 24-27, 2011, in Vancouver, British Columbia, Canada, jointly with the International Symposium on Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials (PFM). Over a period of four days, approximately 400 scientists, engineers, and students from around the world presented their work and discussed the latest developments in the field of ferroelectrics, related materials, and their applications. It is particularly encouraging to see that a large number of students (115) were attracted to the joint conference and presented high-quality research works. This trend is not only important to this conference series, but more importantly, it is vital to the future of the ferroelectrics field.

  9. A reflecting, steepening, and breaking internal tide in a submarine canyon

    Science.gov (United States)

    Alberty, M. S.; Billheimer, S.; Hamann, M. M.; Ou, C. Y.; Tamsitt, V.; Lucas, A. J.; Alford, M. H.

    2017-08-01

    Submarine canyons are common features of the coastal ocean. Although they are known to be hotspots of turbulence that enhance diapycnal transport in their stratified waters, the dynamics of canyon mixing processes are poorly understood. Most studies of internal wave dynamics within canyons have focused on a handful of canyons with along-axis slopes less steep than semidiurnal (D2) internal wave characteristics (subcritical). Here, we present the first tidally resolving observations within a canyon with a steeply sloping axis (supercritical). A process study consisting of two 24 h shipboard stations and a profiling mooring was conducted in the La Jolla Canyon off the coast of La Jolla, CA. Baroclinic energy flux is oriented up-canyon and decreases from 182 ±18 W m-1 at the canyon mouth to 46±5 W m-1 near the head. The ratio of horizontal kinetic energy to available potential energy and the observed group speed of each mode are lower than expected for freely propagating D2 internal waves at each station, indicating partial reflection. Harmonic analysis reveals that variance is dominated by the D2 tide. Moving up-canyon, the relative importance of D2 decreases and its higher harmonics are needed to account for a majority of the observed variance, indicating steepening. Steep internal tides cause large isopycnal displacements (˜50 m in 100 m water depth) and high strain events. These events coincide with enhanced O(10-7-10-5 m2 s-3) dissipation of turbulent kinetic energy at mid-depths.

  10. Liability for nuclear damage: an international perspective. Reflections on the revision of the Vienna Convention

    Energy Technology Data Exchange (ETDEWEB)

    Lopuski, J.

    1993-12-31

    This book deals with deals of the complex issues of liability and compensation for nuclear damage which have been considered in the course of the work of the IAEA concerning the revision of the Vienna Convention on nuclear liability. It presents, in an orderly way, personal reflections of its author based on his experience gathered in years 1989-1992 when participating in this work. Necessarily it contains in some of its parts references to documents of the IAEA Standing Committee on Nuclear Liability; these documents because of their length could not be reproduced. Consequently these parts may not be fully intelligible for those who have not participated in or closely followed the Committee`s work. The IAEA work on liability for nuclear damage was initiated in the wake of the impact made on the world`s public opinion by the Chernobyl incident and its transboundary effects; issues of international state liability and full compensation have been raised. But humanitarian ideas have quickly been confronted with cold calculations of the cost of financial protection for victims and an open unwillingness of some nuclear states has been manifested. After three years of discussions no wide consensus could be reached on some basic issues, such as: relationship between international state and civil liability regimes, structure of international legislation, concept of nuclear damage, limits of compensation, role of public funds or jurisdiction. The author presents his approach to these controversial issue, trying to provide at the same time a theoretical outline for the future international legislation on nuclear liability. (author).

  11. Benchmarking of HEU Mental Annuli Critical Assemblies with Internally Reflected Graphite Cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Xiaobo, Liu; Bess, John D.; Marshall, Margaret A.

    2016-09-01

    Three experimental configurations of critical assemblies, performed in 1963 at the Oak Ridge Critical Experiment Facility, which are assembled using three different diameter HEU annuli (15-9 inches, 15-7 inches and 13-7 inches) metal annuli with internally reflected graphite cylinder are evaluated and benchmarked. The experimental uncertainties which are 0.00055, 0.00055 and 0.00055 respectively, and biases to the detailed benchmark models which are -0.00179, -0.00189 and -0.00114 respectively, were determined, and the experimental benchmark keff results were obtained for both detailed and simplified model. The calculation results for both detailed and simplified models using MCNP6-1.0 and ENDF VII.1 agree well to the benchmark experimental results with a difference of less than 0.2%. These are acceptable benchmark experiments for inclusion in the ICSBEP Handbook.

  12. Maintaining a stationary laser footprint during angular scan in internal-reflection experiments.

    Science.gov (United States)

    Fontana, Eduardo; Cavalcanti, Gustavo Oliveira

    2013-11-10

    In internal-reflection metrology using prisms, the prism is usually mounted on a rotation/translation stage to enable adjusting angle and location of the laser footprint on the surface. If a visual inspection method is used to find the laser footprint, the task becomes impossible if invisible radiation in the near infrared is employed. In addition, it may be desirable to perform angular scan experiments with a stationary footprint on the surface during scans, or even to automatically probe specific points on an extended prism face for predetermined incidence angles. In this paper, a formulation is developed to determine the required translation along the prism face to allow maintaining the laser footprint stationary under a given rotation. A web-based app developed under the scope of this work demonstrates the applicability of the approach for silica, BK7 and SF2 glasses, in the wavelength range from 500 to 1500 nm and for an arbitrary geometry of the glass prism.

  13. An internally reflecting Cherenkov detector (DIRC): Properties of the fused silica radiators

    International Nuclear Information System (INIS)

    Adam, I.; Aston, D.

    1997-11-01

    The DIRC, a new type of ring-imaging Cherenkov detector that images internally reflected Cherenkov light, is being constructed as the main hadronic particle identification component of the BABAR detector at SLAC. The device makes use of 5 meter long fused silica (colloquially called quartz) bars, which serve both as the Cherenkov radiators and as light pipes for transmitting the light to an array of photo-multiplier tubes. This paper describes a program of research and development aimed at determining whether bars that meet the stringent requirements of the DIRC can be obtained from commercial sources. The results of studies of bulk absorption of fused silica, surface finish, radiation damage and bulk inhomogeneities are discussed

  14. Analysis of thin-film polymers using attenuated total internal reflection-Raman microspectroscopy.

    Science.gov (United States)

    Tran, Willie; Tisinger, Louis G; Lavalle, Luis E; Sommer, André J

    2015-01-01

    Two methods commonly employed for molecular surface analysis and thin-film analysis of microscopic areas are attenuated total reflection infrared (ATR-IR) microspectroscopy and confocal Raman microspectroscopy. In the former method, the depth of the evanescent probe beam can be controlled by the wavelength of light, the angle of incidence, or the refractive index of the internal reflection element. Because the penetration depth is proportional to the wavelength of light, one could interrogate a smaller film thickness by moving from the mid-infrared region to the visible region employing Raman spectroscopy. The investigation of ATR Raman microspectroscopy, a largely unexplored technique available to Raman microspectroscopy, was carried out. A Renishaw inVia Raman microscope was externally modified and used in conjunction with a solid immersion lens (SIL) to perform ATR Raman experiments. Thin-film polymer samples were analyzed to explore the theoretical sampling depth for experiments conducted without the SIL, with the SIL, and with the SIL using evanescent excitation. The feasibility of micro-ATR Raman was examined by collecting ATR spectra from films whose thickness measured from 200 to 60 nm. Films of these thicknesses were present on a much thicker substrate, and features from the underlying substrate did not become visible until the thin film reached a thickness of 68 nm.

  15. A hybrid x-ray and microscopy method for diametrical profile measurement of internal holes in steel components

    Science.gov (United States)

    Liu, T.; Malcolm, A. A.; Yin, X. M.; Liew, S. J.; Prawiradiraja, T. P.

    2008-09-01

    High-resolution X-ray is now an essential tool for internal defect and structure inspection in electronics and advanced materials industry. However, it is always a challenge to use it for accurate dimensional measurement due to the nature of the fan-beam X-ray source, particularly for cylindrical objects. This paper presents a novel hybrid X-ray and microscopy method for the profile measurement of the internal hole of a cylinder-shaped steel component. The part to be measured has a beer bottle shape but is open at the bottom side. The objective is to measure the diametrical profile of the internal hole with an accuracy of about 10μm. Traditionally this is measured with using a microscope after cutting and polishing the specimen. This is not only a tedious work, but is also inaccurate due to the uncertainty in cutting and polishing. This report demonstrates that the two edge-profiles of the internal hole can be obtained with X-ray inspection by sequentially placing each of them at the central of the X-ray beam so that the fan-beam effect can be minimized. The resolution of the X-ray inspection is about 6µm under a 20x magnification. Subsequently, the diameter of the hole is measured at two positions through the open end using a microscope with a 20x and a 10x objectives respectively. The results obtained with the two methods are then combined to generate the whole diametrical profile of the internal hole.

  16. Unusual conversations: A reflection on the mechanics of internationally engaged public scholarship

    Directory of Open Access Journals (Sweden)

    Jonathan Damiani

    2016-09-01

    Full Text Available This article analyses the civic engagement pathways of researchers from the Asia-Pacific and the United States in an effort to see how the principles of what American  scholars consider publicly engaged research and creative practice are being enacted in research sites across the globe. The purpose of this ongoing project is to focus on finding ways of connecting American scholars with a network of higher education and research institutions that hold a commitment and passion for social responsibility and civic engagement as it impacts education, research and service for community development overseas. The narrative includes the voices and perspectives of colleagues dedicated to engaged scholarship from across the new region in which I work (the Asia-Pacific, alongside the voices of some of Imagining America’s (IA 2014 National Conference participants. These conversations serve as a critical reflection on the mechanics of doing public scholarship overseas and frame a new model of internationally engaged scholarship. Keywords: Internationally engaged public scholarship, unusual conversations

  17. Stimulus-dependent EEG activity reflects internal updating of tactile working memory in humans.

    Science.gov (United States)

    Spitzer, Bernhard; Blankenburg, Felix

    2011-05-17

    Despite recent advances in uncovering the neural signature of tactile working memory processing in animals and humans, the representation of internally modified somatosensory working memory content has not been studied so far. Here, recording EEG in human participants (n = 25) performing a modified delayed match-to-sample task allowed us to disambiguate internally driven memory processing from encoding-related delay activity. After presentation of two distinct vibrotactile frequencies to different index fingers, a visual cue indicated which of the two previous stimuli had to be maintained in working memory throughout a retention interval for subsequent frequency discrimination against a probe stimulus. During cued stimulus maintenance, α activity (8-13 Hz) over early somatosensory cortices was lateralized according to the cued tactile stimulus, even though the location of the stimuli was task irrelevant. The task-relevant memory content, in contrast, was found to be represented in right prefrontal cortex. The key finding was that the visually presented instructions triggered systematic modulations of prefrontal β-band activity (20-25 Hz), which selectively reflected the to-be-maintained frequency of the cued tactile vibration. The results expand previous evidence for parametric representations of vibrotactile frequency in the prefrontal cortex and corroborate a central role of dynamic β-band synchronization during active processing of an analog stimulus quantity in human working memory. In particular, our findings suggest that such processing supports not only sustained maintenance but also purposeful modification and updating of the task-relevant working memory contents.

  18. New modeling of reflection interference contrast microscopy including polarization and numerical aperture effects: application to nanometric distance measurements and object profile reconstruction.

    Science.gov (United States)

    Theodoly, O; Huang, Z-H; Valignat, M-P

    2010-02-02

    We have developed a new and improved optical model of reflection interference contrast microscopy (RICM) to determine with a precision of a few nanometers the absolute thickness h of thin films on a flat surface in immersed conditions. The model takes into account multiple reflections between a planar surface and a multistratified object, finite aperture illumination (INA), and, for the first time, the polarization of light. RICM intensity I is typically oscillating with h. We introduce a new normalization procedure that uses the intensity extrema of the same oscillation order for both experimental and theoretical intensity values and permits us to avoid significant error in the absolute height determination, especially at high INA. We also show how the problem of solution degeneracy can be solved by taking pictures at two different INA values. The model is applied to filled polystyrene beads and giant unilamellar vesicles of radius 10-40 microm sitting on a glass substrate. The RICM profiles I(h) can be fitted for up to two to three oscillation orders, and extrema positions are correct for up to five to seven oscillation orders. The precision of the absolute distance and of the shape of objects near a substrate is about 5 nm in a range from 0 to 500 nm, even under large numerical aperture conditions. The method is especially valuable for dynamic RICM experiments and with living cells where large illumination apertures are required.

  19. A novel technique using potassium permanganate and reflectance confocal microscopy to image biofilm extracellular polymeric matrix reveals non-eDNA networks in Pseudomonas aeruginosa biofilms.

    Science.gov (United States)

    Swearingen, Matthew C; Mehta, Ajeet; Mehta, Amar; Nistico, Laura; Hill, Preston J; Falzarano, Anthony R; Wozniak, Daniel J; Hall-Stoodley, Luanne; Stoodley, Paul

    2016-02-01

    Biofilms are etiologically important in the development of chronic medical and dental infections. The biofilm extracellular polymeric substance (EPS) determines biofilm structure and allows bacteria in biofilms to adapt to changes in mechanical loads such as fluid shear. However, EPS components are difficult to visualize microscopically because of their low density and molecular complexity. Here, we tested potassium permanganate, KMnO4, for use as a non-specific EPS contrast-enhancing stain using confocal laser scanning microscopy in reflectance mode. We demonstrate that KMnO4 reacted with EPS components of various strains of Pseudomonas, Staphylococcus and Streptococcus, yielding brown MnO2 precipitate deposition on the EPS, which was quantifiable using data from the laser reflection detector. Furthermore, the MnO2 signal could be quantified in combination with fluorescent nucleic acid staining. COMSTAT image analysis indicated that KMnO4 staining increased the estimated biovolume over that determined by nucleic acid staining alone for all strains tested, and revealed non-eDNA EPS networks in Pseudomonas aeruginosa biofilm. In vitro and in vivo testing indicated that KMnO4 reacted with poly-N-acetylglucosamine and Pseudomonas Pel polysaccharide, but did not react strongly with DNA or alginate. KMnO4 staining may have application as a research tool and for diagnostic potential for biofilms in clinical samples. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Light Microscopy Module: On-Orbit Microscope Planned for the Fluids Integrated Rack on the International Space Station

    Science.gov (United States)

    Motil, Susan M.

    2002-01-01

    The Light Microscopy Module (LMM) is planned as a remotely controllable, automated, on-orbit facility, allowing flexible scheduling and control of physical science and biological science experiments within the Fluids Integrated Rack (FIR) on the International Space Station. Initially four fluid physics experiments in the FIR will use the LMM the Constrained Vapor Bubble, the Physics of Hard Spheres Experiment-2, Physics of Colloids in Space-2, and Low Volume Fraction Entropically Driven Colloidal Assembly. The first experiment will investigate heat conductance in microgravity as a function of liquid volume and heat flow rate to determine, in detail, the transport process characteristics in a curved liquid film. The other three experiments will investigate various complementary aspects of the nucleation, growth, structure, and properties of colloidal crystals in microgravity and the effects of micromanipulation upon their properties.

  1. Nondestructive imaging of buried interfaces in SiC and GaN Schottky contacts using scanning internal photoemission microscopy

    Science.gov (United States)

    Shiojima, Kenji; Yamamoto, Shingo; Kihara, Yuhei; Mishima, Tomoyoshi

    2015-04-01

    We demonstrate a nondestructive characterization of buried interfaces in metal/wide-bandgap semiconductor contacts by using scanning internal photoemission microscopy. For Ni/n-SiC contacts annealed at temperatures above 400 °C, a reduction of the Schottky barrier height owing to partial interfacial reaction was visualized. In Au/Ni/n-GaN contacts, upon annealing at 400 °C, thermal degradation from a scratch on the dot was observed. Forward current-voltage curves were reproduced by lowering the Schottky barrier height and the area of the reacted regions by using this method. The present imaging method exploits its nondestructive highly sensitive extinction for characterizing the contacts formed on wide-gap materials.

  2. Proceedings of the international conference on advances in electron microscopy and related techniques and thirty first annual meeting of EMSI: souvenir and book of abstracts

    International Nuclear Information System (INIS)

    2010-01-01

    The International Conference on Advances in Electron Microscopy and Related Techniques and thirty first Annual Meeting of EMSI (EMSI-2010) jointly organized by the Electron Microscopy Society of India (EMSI) and Bhabha Atomic Research Centre (BARC) was held at BARC, Mumbai, India during March 8-10, 2010. This conference aims to provide an opportunity for young scientists and researchers to interact with eminent scientists and specialists working in frontier areas of science and technology and also to build expertise in the micro-chemical characterization at nanoscale level of all kinds of materials using advanced Electron Microscopy Techniques. Papers relevant to INIS are indexed separately

  3. Rheology and Confocal Reflectance Microscopy as Probes of Mechanical Properties and Structure during Collagen and Collagen/Hyaluronan Self-Assembly

    Science.gov (United States)

    Yang, Ya-li; Kaufman, Laura J.

    2009-01-01

    In this work, the gelation of three-dimensional collagen and collagen/hyaluronan (HA) composites is studied by time sweep rheology and time lapse confocal reflectance microscopy (CRM). To investigate the complementary nature of these techniques, first collagen gel formation is investigated at concentrations of 0.5, 1.0, and 1.5 mg/mL at 37°C and 32°C. The following parameters are used to describe the self-assembly process in all gels: the crossover time (tc), the slope of the growth phase (kg), and the arrest time (ta). The first two measures are determined by rheology, and the third by CRM. A frequency-independent rheological measure of gelation, tg, is also measured at 37°C. However, this quantity cannot be straightforwardly determined for gels formed at 32°C, indicating that percolation theory does not fully capture the dynamics of collagen network formation. The effects of collagen concentration and gelation temperature on kg, tc, and ta as well as on the mechanical properties and structure of these gels both during gelation and at equilibrium are elucidated. Composite collagen/HA gels are also prepared, and their properties are monitored at equilibrium and during gelation at 37°C and 32°C. We show that addition of HA subtly alters mechanical properties and structure of these systems both during the gelation process and at equilibrium. This occurs in a temperature-dependent manner, with the ratio of HA deposited on collagen fibers versus that distributed homogeneously between fibers increasing with decreasing gelation temperature. In addition to providing information on collagen and collagen/HA structure and mechanical properties during gelation, this work shows new ways in which rheology and microscopy can be used complementarily to reveal details of gelation processes. PMID:19217873

  4. A Marked Poisson Process Driven Latent Shape Model for 3D Segmentation of Reflectance Confocal Microscopy Image Stacks of Human Skin

    Science.gov (United States)

    Ghanta, Sindhu; Jordan, Michael I.; Kose, Kivanc; Brooks, Dana H.; Rajadhyaksha, Milind; Dy, Jennifer G.

    2016-01-01

    Segmenting objects of interest from 3D datasets is a common problem encountered in biological data. Small field of view and intrinsic biological variability combined with optically subtle changes of intensity, resolution and low contrast in images make the task of segmentation difficult, especially for microscopy of unstained living or freshly excised thick tissues. Incorporating shape information in addition to the appearance of the object of interest can often help improve segmentation performance. However, shapes of objects in tissue can be highly variable and design of a flexible shape model that encompasses these variations is challenging. To address such complex segmentation problems, we propose a unified probabilistic framework that can incorporate the uncertainty associated with complex shapes, variable appearance and unknown locations. The driving application which inspired the development of this framework is a biologically important segmentation problem: the task of automatically detecting and segmenting the dermal-epidermal junction (DEJ) in 3D reflectance confocal microscopy (RCM) images of human skin. RCM imaging allows noninvasive observation of cellular, nuclear and morphological detail. The DEJ is an important morphological feature as it is where disorder, disease and cancer usually start. Detecting the DEJ is challenging because it is a 2D surface in a 3D volume which has strong but highly variable number of irregularly spaced and variably shaped “peaks and valleys”. In addition, RCM imaging resolution, contrast and intensity vary with depth. Thus a prior model needs to incorporate the intrinsic structure while allowing variability in essentially all its parameters. We propose a model which can incorporate objects of interest with complex shapes and variable appearance in an unsupervised setting by utilizing domain knowledge to build appropriate priors of the model. Our novel strategy to model this structure combines a spatial Poisson process

  5. Optical and Scanning Electron Microscopy of the Materials International Space Station Experiment (MISSE) Spacecraft Silicone Experiment

    Science.gov (United States)

    Hung, Ching-cheh; de Groh, Kim K.; Banks, Bruce A.

    2012-01-01

    Under a microscope, atomic oxygen (AO) exposed silicone surfaces are crazed and seen as "islands" separated by numerous crack lines, much analogous to mud-tile cracks. This research characterized and compared the degree of AO degradation of silicones by analyzing optical microscope images of samples exposed to low Earth orbit (LEO) AO as part of the Spacecraft Silicone Experiment. The Spacecraft Silicone Experiment consisted of eight DC 93-500 silicone samples exposed to eight different AO fluence levels (ranged from 1.46 to 8.43 10(exp 21) atoms/sq cm) during two different Materials International Space Station Experiment (MISSE) missions. Image analysis software was used to analyze images taken using a digital camera. To describe the morphological degradation of each AO exposed flight sample, three different parameters were selected and estimated: (1) average area of islands was determined and found to be in the 1000 to 3100 sq mm range; (2) total length of crack lines per unit area of the sample surface were determined and found to be in the range of 27 to 59 mm of crack length per sq mm of sample surface; and (3) the fraction of sample surface area that is occupied by crack lines was determined and found to be in the 25 to 56 percent range. In addition, average crack width can be estimated from crack length and crack area measurements and was calculated to be about 10 mm. Among the parameters studied, the fraction of sample surface area that is occupied by crack lines is believed to be most useful in characterizing the degree of silicone conversion to silicates by AO because its value steadily increases with increasing fluence over the entire fluence range. A series of SEM images from the eight samples exposed to different AO fluences suggest a complex sequence of surface stress due to surface shrinkage and crack formation, followed by re-distribution of stress and shrinking rate on the sample surface. Energy dispersive spectra (EDS) indicated that upon AO

  6. A total internal reflection-fluorescence correlation spectroscopy setup with pulsed diode laser excitation.

    Science.gov (United States)

    Weger, Lukas; Hoffmann-Jacobsen, Kerstin

    2017-09-01

    Fluorescence correlation spectroscopy (FCS) measures fluctuations in a (sub-)femtoliter volume to analyze the diffusive behavior of fluorescent particles. This highly sensitive method has proven to be useful for the analysis of dynamic biological systems as well as in chemistry, physics, and material sciences. It is routinely performed with commercial fluorescence microscopes, which provide a confined observation volume by the confocal technique. The evanescent wave of total internal reflectance (TIR) is used in home-built systems to permit a surface sensitive FCS analysis. We present a combined confocal and TIR-FCS setup which uses economic low-power pulsed diode lasers for excitation. Excitation and detection are coupled to time-correlated photon counting hardware. This allows simultaneous fluorescence lifetime and FCS measurements in a surface-sensitive mode. Moreover, the setup supports fluorescence lifetime correlation spectroscopy at surfaces. The excitation can be easily switched between TIR and epi-illumination to compare the surface properties with those in liquid bulk. The capabilities of the presented setup are demonstrated by measuring the diffusion coefficients of a free dye molecule, a labeled polyethylene glycol, and a fluorescent nanoparticle in confocal as well as in TIR-FCS.

  7. Frustrated total internal reflection in organic light-emitting diodes employing sphere cavity embedded in polystyrene

    International Nuclear Information System (INIS)

    Zhu, Peifen

    2016-01-01

    The light extraction efficiency of top-emitting organic light-emitting diodes (OLEDs) is numerically investigated employing the finite-difference time-domain method. The periodic nanostructures formed by embedding the sphere arrays in polystyrene (PS) are placed on top of OLED to frustrate the total internal reflection at the interface between OLED and free space. These nanostructures serve as an intermediate medium to extract the light out of OLED devices. Efficiently coupling both evanescent waves and propagation waves into spheres and subsequently extracting these light waves out of the sphere is key to achieving high extraction efficiency. By tuning the thickness of PS layer, both of the in-coupling efficiency and out-coupling efficiency are optimized for achieving high light extraction efficiency. Thicker PS layer results in higher in-coupling efficiency in sphere while the thinner PS layer leads to higher out-coupling efficiency. Thus the maximum light extraction is a trade-off between the in-coupling efficiency and out-coupling efficiency. The study shows that light extraction efficiency of 89% can be achieved by embedding 0.90 μm TiO 2 sphere in 0.30 μm PS layer with optimized in-coupling efficiency, out-coupling efficiency and cavity effect. (paper)

  8. Extraction of light trapped due to total internal reflection using porous high refractive index nanoparticle films.

    Science.gov (United States)

    Mao, Peng; Sun, Fangfang; Yao, Hanchao; Chen, Jing; Zhao, Bo; Xie, Bo; Han, Min; Wang, Guanghou

    2014-07-21

    TiO₂ nanoparticle layers composed of columnar TiO₂ nanoparticle piles separated with nanoscale pores were fabricated on the bottom surface of the hemispherical glass prism by performing gas phase cluster beam deposition at glancing incidence. The porosity as well as the refractive index of the nanoparticle layer was precisely tuned by the incident angle. Effective extraction of the light trapped in the substrate due to total internal reflection with the TiO₂ nanoparticle layers was demonstrated and the extraction efficiency was found to increase with the porosity. An enhanced Rayleigh scattering mechanism, which results from the columnar aggregation of the nanoparticles as well as the strong contrast in the refractive index between pores and TiO₂ nanoparticles in the nanoporous structures, was proposed. The porous TiO₂ nanoparticle coatings were fabricated on the surface of GaN LEDs to enhance their light output. A nearly 92% PL enhancement as well as a 30% EL enhancement was observed. For LED applications, the enhanced light extraction with the TiO₂ nanoparticle porous layers can be a supplement to the microscale texturing process for light extraction enhancement.

  9. Gold nanoparticle-polydimethylsiloxane films reflect light internally by optical diffraction and Mie scattering

    Science.gov (United States)

    Dunklin, Jeremy R.; Forcherio, Gregory T.; Roper, D. Keith

    2015-08-01

    Optical properties of polymer films embedded with plasmonic nanoparticles (NPs) are important in many implementations. In this work, optical extinction by polydimethylsiloxane (PDMS) films containing gold (Au) NPs was enhanced at resonance compared to AuNPs in suspensions, Beer-Lambert law, or Mie theory by internal reflection due to optical diffraction in 16 nm AuNP-PDMS films and Mie scattering in 76 nm AuNP-PDMS films. Resonant extinction per AuNP for 16 nm AuNPs with negligible resonant Mie scattering was enhanced up to 1.5-fold at interparticle separation (i.e., Wigner-Seitz radii) comparable to incident wavelength. It was attributable to diffraction through apertures formed by overlapping electric fields of adjacent, resonantly excited AuNPs at Wigner-Seitz radii equal to or less than incident wavelengths. Resonant extinction per AuNP for strongly Mie scattering 76 nm AuNPs was enhanced up to 1.3-fold at Wigner-Seitz radii four or more times greater than incident wavelength. Enhanced light trapping from diffraction and/or scattering is relevant to optoelectronic, biomedical, and catalytic activity of substrates embedded with NPs.

  10. Tunable Wide-Angle Tunneling in Graphene-Assisted Frustrated Total Internal Reflection

    Science.gov (United States)

    Tran, Thang Q.; Lee, Sangjun; Heo, Hyungjun; Kim, Sangin

    2016-01-01

    Electrically tunable permittivity of graphene provides an excellent tool in photonic device design. Many previous works on graphene-based photonic devices relied on variable absorption in graphene, which is naturally small in the optical region, and resonant structures to enhance it. Here we proposed a novel scheme to control evanescent coupling strength by inserting two graphene layers to a frustrated total internal reflection (FTIR) configuration. The resulting structure behaves in a drastically different way from the original FTIR: optical transmission though the structure can be electrically controlled from ~10-5 to ~1 with little dependency on angle of incidence. This unique feature stems from the fact that the permittivity of doped graphene can be close to zero at a certain photon energy. The electrical controllability of evanescent coupling strength can enable novel design of optical devices. As a proof-of-concept, we designed a waveguide-type optical modulator of a novel operation principle: transmission modulation depends on the electrically controlled existence of a guided-mode of the waveguide, not the variation of the ohmic loss of graphene, resulting in a low insertion loss and a small device footprint.

  11. Attenuated total internal reflection Fourier transform infrared spectroscopy: a quantitative approach for kidney stone analysis.

    Science.gov (United States)

    Gulley-Stahl, Heather J; Haas, Jennifer A; Schmidt, Katherine A; Evan, Andrew P; Sommer, André J

    2009-07-01

    The impact of kidney stone disease is significant worldwide, yet methods for quantifying stone components remain limited. A new approach requiring minimal sample preparation for the quantitative analysis of kidney stone components has been investigated utilizing attenuated total internal reflection Fourier transform infrared spectroscopy (ATR-FT-IR). Calcium oxalate monohydrate (COM) and hydroxylapatite (HAP), two of the most common constituents of urinary stones, were used for quantitative analysis. Calibration curves were constructed using integrated band intensities of four infrared absorptions versus concentration (weight %). The correlation coefficients of the calibration curves range from 0.997 to 0.93. The limits of detection range from 0.07 +/- 0.02% COM/HAP where COM is the analyte and HAP is the matrix, to 0.26 +/- 0.07% HAP/COM where HAP is the analyte and COM is the matrix. This study shows that linear calibration curves can be generated for the quantitative analysis of stone mixtures provided the system is well understood especially with respect to particle size.

  12. Reflectance confocal microscopy is a useful non-invasive tool in the in vivo diagnosis of pigmented basal cell carcinoma in Asians.

    Science.gov (United States)

    Chuah, Sai Yee; Tee, Shang Ian; Tan, Wee Ping; Lee, Siong See Joyce; Ng, See Ket; Chua, Sze Hon; Thng, Tien Guan Steven

    2017-05-01

    The clinical differentiation between pigmented basal cell carcinoma (BCC) and other benign pigmented skin lesions can be challenging even with an additional dermoscopic evaluation, especially if the lesion is small. In vivo reflectance confocal microscopy (RCM) is an emerging, non-invasive imaging tool that allows near-microscopic evaluation of skin lesions. The features of RCM for pigmented BCC and seborrhoeic keratosis have previously been described. However, the use of RCM to differentiate between these clinically and dermoscopically challenging pigmented skin lesions among Asians has not yet been demonstrated. We aimed to evaluate the usefulness of non-invasive RCM to differentiate between clinically and dermoscopically challenging pigmented skin lesions among Asians in a series of 11 lesions. Nine patients with 11 clinically and dermoscopically difficult to distinguish pigmented skin lesions were evaluated by RCM to differentiate between pigmented BCC and benign lesions. In all cases, a histological confirmation of the RCM diagnosis was obtained. The clinical or dermoscopical characteristics were non-specific in all 10 cases. RCM detected features of pigmented BCC in nine patients and seborrhoeic keratosis in one patient. These were all confirmed by histological examination. This case series shows the value of non-invasive in vivo RCM imaging in the differentiation of malignant and benign pigmented lesions. Early diagnosis of small, pigmented BCC allows earlier excision with better prognosis. Future biopsies of benign lesions in cosmetic areas could also be avoided. © 2015 The Australasian College of Dermatologists.

  13. Efficacy of a Daily Protective Moisturizer with High UVB and UVA Photoprotection in Decreasing Ultraviolet Damage: Evaluation by Reflectance Confocal Microscopy

    Directory of Open Access Journals (Sweden)

    Antonio Gomes-Neto

    2017-08-01

    Full Text Available Patients with photodermatoses or actinic keratosis benefit from very high ultraviolet B-ultraviolet A (UVB-UVA photoprotection. However, poor compliance is an issue that jeopardizes adequate protection, leading to disease recurrence. This study evaluated the efficacy of a daily protective moisturizer with high UVB and UVA photoprotection applied 8 h before irradiation. A monocentric, open-label, prospective, control pilot study was performed including 10 patients. Patients were irradiated with UVB and UVA before and 8 h after topical application of the product. Reflectance confocal microscopy (RCM assessment was performed 24 h later. Clinical assessment showed a statistically significant increase in minimal erythema dose (MED after application of the product (p <0.001. Signs of UV damage according to RCM were not observed on photoprotected skin (p < 0.05. Skin irradiated 8 h after applying a daily protective moisturizer presented an increase in MED and RCM findings that equal the findings for non-irradiated skin

  14. Meaning, Internalization, and Externalization: Toward a Fuller Understanding of the Process of Reflection and Its Role in the Construction of the Self

    Science.gov (United States)

    Le Cornu, Alison

    2009-01-01

    The study of the process of reflection has a dignified history. However, few have linked reflection to the development of the self in such a way that the form of reflection is understood to influence the resultant type of self. This article explores the process of reflection using a framework of meaning making, internalization, and externalization…

  15. How Is Buddhism Relevant to Career Counseling in an International High School in Hong Kong? A Counsellor's Reflection

    Science.gov (United States)

    Ng, Vinci; Yuen, Mantak

    2015-01-01

    This paper reflects upon the relevance of Buddhism to counselling in general and to career counseling in particular by discussing a program implemented at an international school in Hong Kong. The authors provide an analysis of the pertinent literature related to relevant concepts within Buddhism. This topic has not yet been adequately researched…

  16. Reflections on International Comparative Education Survey Methodology: A Case Study of the European Survey on Language Competences

    Science.gov (United States)

    Ashton, Karen

    2016-01-01

    This paper reflects on the methodology used in international comparative education surveys by conducting a systematic review of the European Survey on Language Competences (ESLC). The ESLC was administered from February to March 2011, with final results released in June 2012. The survey tested approximately 55,000 students across 14 European…

  17. Internal potential mapping of charged solid-state-lithium ion batteries using in situ Kelvin probe force microscopy.

    Science.gov (United States)

    Masuda, Hideki; Ishida, Nobuyuki; Ogata, Yoichiro; Ito, Daigo; Fujita, Daisuke

    2017-01-05

    Solid-state-lithium ion batteries (SS-LIBs) are a promising candidate for next-generation energy storage devices. Novel methods for characterizing electrochemical reactions occurring during battery operation at the nanoscale are highly required for understanding the fundamental working principle and improving the performance of the devices. In this work, we combined Ar ion milling under non-atmospheric conditions with in situ cross-sectional Kelvin probe force microscopy (KPFM) for direct imaging of the internal electrical potential distribution of the SS-LIBs. We succeeded in the direct visualization of the change in the potential distribution of a cathode composite electrode (a mixture of the active materials, solid electrolytes, and conductive additives) arising from battery charging (electrochemical reaction). The observed results provided several insights into battery operation, such as the behavior of Li ions and inhomogeneity of electrochemical reactions in the electrode. Our method paves the way to characterize the fundamental aspects of SS-LIBs for the improvement of device performance, including the evaluation of the distribution of the Li ion depleted regions, visualization of the conductive paths, and analysis of the cause of degradation.

  18. Electron microscopy of surfaces

    International Nuclear Information System (INIS)

    Venables, J.A.

    1981-01-01

    Electron beam techniques used to study clean surfaces and surface processes on a microscopic scale are reviewed. Recent experimental examples and possible future developments are discussed. Special emphasis is given to (i) transmission diffraction and microscopy techniques, including atomic imaging; (ii) Auger microscopy on bulk and thin film samples; (iii) secondary electron microscopy, especially low energy secondaries for work-function imaging and photoelectron imaging; and (iv) reflection electron microscopy and diffraction. (orig.)

  19. Determination of lead in clay enameled by X-ray fluorescence technique in Total reflection and by Scanning Electron Microscopy; Determinacion de plomo en esmaltado de barro por Fluorescencia de rayos X en reflexion total y Microscopia Electronica de Barrido

    Energy Technology Data Exchange (ETDEWEB)

    Zarazua O, G.; Carapia M, L. [Instituto Nacional de Investigaciones Nucleares, C.P. 52045 Estado de Mexico (Mexico)

    2000-07-01

    This work has the objective of determining lead free in the glazed commercial stewing pans using the X-ray fluorescence technique in Total reflection (FRX) and the observation and semiquantitative determination of lead by Analytical Scanning Electron Microscopy (ASEM). (Author)

  20. Fordyce granules and hyperplastic mucosal sebaceous glands as distinctive stigmata in Muir-Torre syndrome patients: characterization with reflectance confocal microscopy.

    Science.gov (United States)

    Ponti, Giovanni; Meschieri, Andrea; Pollio, Annamaria; Ruini, Cristel; Manfredini, Marco; Longo, Caterina; Mandel, Victor D; Ciardo, Silvana; Tomasi, Aldo; Giannetti, Luca; Pellacani, Giovanni

    2015-08-01

    The Muir-Torre syndrome (MTS), a variant of Lynch syndrome (LS), is characterized by the presence of sebaceous skin adenomas and/or carcinomas and keratoacanthomas associated with visceral malignancies. Fordyce granules (FGs) are oral mucosal lesions previously found in association with LS. The aim of this study was to analyze the specific frequency of FGs in sporadic individuals and gene carriers patients with MTS of known mismatch repair genes mutations. The secondary aim was to characterize FGs by means of reflectance confocal microscopy (RCM). A total of 13 patients belonging to nine different genetically unrelated MTS kindreds (MLH1 gene mutation n = 2; MSH2 gene mutation n = 11) and 140 genetically unrelated healthy controls were examined. Depending on the clinical examination of the oral mucosa surface, subjects were categorized as either FGs positive or FGs negative. FGs were diagnosed in 13 of 13 (100%) of MMR gene carriers patients with MTS vs. 9 of 140 (6.4%) controls. The most common site for FGs in MTS was the vestibular oral mucosa, compared with the gingival mandibular and retromandibular pad in controls. RCM examination found multiple sebaceous acinar cells that appear as round or oval hyper-refractive globules and that create a lobular aspects of the sebaceous glands defined as 'moruliform' or 'berry-like' structures. Clinical and RCM evidences of our study suggest that an activation of the sebaceous glands system occurs in patients with MTS. Fordyce granules and intra-oral sebaceous hyperplasia may constitute an additional clinical parameter, which may be adopted to distinguish individuals with highest likelihood of being affected from MTS. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Improving diagnostic sensitivity of combined dermoscopy and reflectance confocal microscopy imaging through double reader concordance evaluation in telemedicine settings: A retrospective study of 1000 equivocal cases.

    Directory of Open Access Journals (Sweden)

    A M Witkowski

    Full Text Available Reflectance confocal microscopy (RCM is an imaging device that permits non-invasive visualization of cellular morphology and has been shown to improve diagnostic accuracy of dermoscopically equivocal cutaneous lesions. The application of double reader concordance evaluation of dermoscopy-RCM image sets in retrospective settings and its potential application to telemedicine evaluation has not been tested in a large study population.To improve diagnostic sensitivity of RCM image diagnosis using a double reader concordance evaluation approach; to reduce mismanagement of equivocal cutaneous lesions in retrospective consultation and telemedicine settings.1000 combined dermoscopy-RCM image sets were evaluated in blind by 10 readers with advanced training and internship in dermoscopy and RCM evaluation. We compared sensitivity and specificity of single reader evaluation versus double reader concordance evaluation as well as the effect of diagnostic confidence on lesion management in a retrospective setting.Single reader evaluation resulted in an overall sensitivity of 95.2% and specificity of 76.3%, with misdiagnosis of 8 melanomas, 4 basal cell carcinomas and 2 squamous cell carcinomas. Combined double reader evaluation resulted in an overall sensitivity of 98.3% and specificity of 65.5%, with misdiagnosis of 1 in-situ melanoma and 2 basal cell carcinomas.Evaluation of dermoscopy-RCM image sets of cutaneous lesions by single reader evaluation in retrospective settings is limited by sensitivity levels that may result in potential mismanagement of malignant lesions. Double reader blind concordance evaluation may improve the sensitivity of diagnosis and management safety. The use of a second check can be implemented in telemedicine settings where expert consultation and second opinions may be required.

  2. Electrochemical, atomic force microscopy and infrared reflection absorption spectroscopy studies of pre-formed mussel adhesive protein films on carbon steel for corrosion protection

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan, E-mail: fanzhang@kth.se [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Div. of Surface and Corrosion Science, Drottning Kristinas vaeg.51, SE-100 44 Stockholm (Sweden); Pan, Jinshan [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Div. of Surface and Corrosion Science, Drottning Kristinas vaeg.51, SE-100 44 Stockholm (Sweden); Claesson, Per Martin [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Div. of Surface and Corrosion Science, Drottning Kristinas vaeg.51, SE-100 44 Stockholm (Sweden); Institute for Surface Chemistry, P.O. Box 5607, SE-114 86 Stockholm (Sweden); Brinck, Tore [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Physical Chemistry, Division of Physical Chemistry, Teknikringen 36, SE-10044 Stockholm (Sweden)

    2012-10-01

    Electrochemical measurements, in situ and ex situ atomic force microscopy (AFM) experiments and infrared reflection absorption spectroscopy (IRAS) analysis were performed to investigate the formation and stability as well as corrosion protection properties of mussel adhesive protein (Mefp-1) films on carbon steel, and the influence of cross-linking by NaIO{sub 4} oxidation. The in situ AFM measurements show flake-like adsorbed protein aggregates in the film formed at pH 9. The ex situ AFM images indicate multilayer-like films and that the film becomes more compact and stable in NaCl solution after the cross-linking. The IRAS results reveal the absorption bands of Mefp-1 on carbon steel before and after NaIO{sub 4} induced oxidation of the pre-adsorbed protein. Within a short exposure time, a certain corrosion protection effect was noted for the pre-formed Mefp-1 film in 0.1 M NaCl solution. Cross-linking the pre-adsorbed film by NaIO{sub 4} oxidation significantly enhanced the protection efficiency by up to 80%. - Highlights: Black-Right-Pointing-Pointer Mussel protein was tested as 'green' corrosion protection strategy for steel. Black-Right-Pointing-Pointer At pH 9, the protein adsorbs on carbon steel and forms a multilayer-like film. Black-Right-Pointing-Pointer NaIO{sub 4} leads to structural changes and cross-linking of the protein film. Black-Right-Pointing-Pointer Cross-linking results in a dense and compact film with increased stability. Black-Right-Pointing-Pointer Cross-linking of preformed film significantly enhances the corrosion protection.

  3. Improving Diagnostic Accuracy of Dermoscopically Equivocal Pink Cutaneous Lesions with Reflectance Confocal Microscopy in Telemedicine Settings: Double Reader Concordance Evaluation of 316 Cases.

    Science.gov (United States)

    Łudzik, J; Witkowski, A M; Roterman-Konieczna, I; Bassoli, S; Farnetani, F; Pellacani, G

    2016-01-01

    Solitary pink lesions in differential diagnosis with hypopigmented/amelanotic melanoma present a diagnostic challenge in daily practice and are regularly referred for second expert opinion. Reflectance confocal microscopy (RCM) has been shown to improve diagnostic accuracy of dermoscopically equivocal pink lesions. No studies have been performed to evaluate the effect of adding a second expert reader and automatic removal of lesions with discordant management recommendations and its potential effect on diagnostic sensitivity and final management of these lesions in retrospective or telemedicine settings. To improve diagnostic accuracy and reduce potential mismanagement of dermoscopically equivocal pink cutaneous lesions by implementing double reader concordance evaluation of RCM images. 316 dermoscopically equivocal pink lesions with dermoscopy-RCM image sets were evaluated retrospectively. Accuracy of three readers was evaluated by single reader evaluation of dermoscopy only and dermoscopy-RCM image sets and finally by double reader evaluation of dermoscopy-RCM image sets. Lesions with discordant diagnosis between two readers were automatically recommended for excision. Dermoscopy only evaluation resulted in an overall sensitivity of 95.9% and specificity of 33.6%, with 1 of 12 amelanotic melanomas mismanaged. Dermoscopy-RCM image set single reader evaluation resulted in an overall sensitivity of 93.9% and overall specificity of 54.2%, with 1 of 12 melanomas mismanaged. Dermoscopy-RCM image set double reader concordance evaluation resulted in an overall sensitivity of 98.3% and specificity of 42.7%, with no amelanotic melanoma mismanagement. Evaluation of dermoscopy-RCM image sets of equivocal pink lesions by a single reader in telemedicine settings is limited by the potential for misdiagnosis of dangerous malignant lesions. Double reader concordance evaluation with automatic referral of lesions for removal in the case of discordant diagnosis improves the

  4. Communication Education and International Audiences: Reflections on Instructional Challenges and Pedagogical Strategy

    Science.gov (United States)

    Campbell, Heather; Strawser, Michael G.; George, Stephen

    2016-01-01

    As the movement toward international education continues, institutions must be proficient when reaching and teaching international students. Instructors should engage unique learning styles, address individual student needs, and take part in additional training to effectively teach international student learners. These instructional imperatives…

  5. Do people ruminate because they haven't digested their goals? The relations of rumination and reflection to goal internalization and ambivalence

    DEFF Research Database (Denmark)

    Thomsen, Dorthe Kirkegaard; Tønnesvang, Jan; Schnieber, Anette

    2011-01-01

    , and internalization of self-regulation and goals. In Study 1, rumination was related to less internalized self-regulation, whereas reflection was related to more internalized self-regulation. In Study 2, rumination was related to less internalized self-regulation and goals as well as to more avoidance- and extrinsic...

  6. Internal versus external service quality: reflections of employees and customers in the mirror

    Directory of Open Access Journals (Sweden)

    Emir Ganic

    2017-09-01

    perceptions of the quality of university services. Perceptions of internal service quality are also positively related to students’ perceptions of reliability, responsiveness and quality assurance. Conclusions: The perceptions of internal service quality by faculty members are positively related to students’ perceptions of quality. Comparing the levels of internal and external service quality will help managers define priorities for allocating resources to improve quality.

  7. All-optical microscope autofocus based on an electrically tunable lens and a totally internally reflected IR laser.

    Science.gov (United States)

    Bathe-Peters, M; Annibale, P; Lohse, M J

    2018-02-05

    Microscopic imaging at high spatial-temporal resolution over long time scales (minutes to hours) requires rapid and precise stabilization of the microscope focus. Conventional and commercial autofocus systems are largely based on piezoelectric stages or mechanical objective actuators. Objective to sample distance is either measured by image analysis approaches or by hardware modules measuring the intensity of reflected infrared light. We propose here a truly all-optical microscope autofocus taking advantage of an electrically tunable lens and a totally internally reflected infrared probe beam. We implement a feedback-loop based on the lateral position of a totally internally reflected infrared laser on a quadrant photodetector, as an indicator of the relative defocus. We show here how to treat the combined contributions due to mechanical defocus and deformation of the tunable lens. As a result, the sample can be kept in focus without any mechanical movement, at rates up to hundreds of Hertz. The device requires only reflective optics and can be implemented at a fraction of the cost required for a comparable piezo-based actuator.

  8. Endoscopic Microscopy

    Directory of Open Access Journals (Sweden)

    Konstantin Sokolov

    2002-01-01

    Full Text Available In vivo endoscopic optical microscopy provides a tool to assess tissue architecture and morphology with contrast and resolution similar to that provided by standard histopathology – without need for physical tissue removal. In this article, we focus on optical imaging technologies that have the potential to dramatically improve the detection, prevention, and therapy of epithelial cancers. Epithelial pre-cancers and cancers are associated with a variety of morphologic, architectural, and molecular changes, which currently can be assessed only through invasive, painful biopsy. Optical imaging is ideally suited to detecting cancer-related alterations because it can detect biochemical and morphologic alterations with sub-cellular resolution throughout the entire epithelial thickness. Optical techniques can be implemented non-invasively, in real time, and at low cost to survey the tissue surface at risk. Our manuscript focuses primarily on modalities that currently are the most developed: reflectance confocal microscopy (RCM and optical coherence tomography (OCT. However, recent advances in fluorescence-based endoscopic microscopy also are reviewed briefly. We discuss the basic principles of these emerging technologies and their current and potential applications in early cancer detection. We also present research activities focused on development of exogenous contrast agents that can enhance the morphological features important for cancer detection and that have the potential to allow vital molecular imaging of cancer-related biomarkers. In conclusion, we discuss future improvements to the technology needed to develop robust clinical devices.

  9. A plastic total internal reflection-based photoluminescence device for enzymatic biosensors

    Science.gov (United States)

    Thakkar, Ishan G.

    Growing concerns for quality of water, food and beverages in developing and developed countries drive sizeable markets for mass-producible, low cost devices that can measure the concentration of contaminant chemicals in water, food, and beverages rapidly and accurately. Several fiber-optic enzymatic biosensors have been reported for these applications, but they exhibit very strong presence of scattered excitation light in the signal for sensing, requiring expensive thin-film filters, and their non-planar structure makes them challenging to mass-produce. Several other planar optical waveguide-based biosensors prove to be relatively costly and more fragile due to constituent materials and the techniques involved in their fabrication. So, a plastic total internal reflection (TIR)-based low cost, low scatter, field-portable device for enzymatic biosensors is fabricated and demonstrated. The design concept of the TIR-based photoluminescent enzymatic biosensor device is explained. An analysis of economical materials with appropriate optical and chemical properties is presented. PMMA and PDMS are found to be appropriate due to their high chemical resistance, low cost, high optical transmittance and low auto-fluorescence. The techniques and procedures used for device fabrication are discussed. The device incorporated a PMMA-based optical waveguide core and PDMS-based fluid cell with simple multi-mode fiber-optics using cost-effective fabrication techniques like molding and surface modification. Several techniques of robustly depositing photoluminescent dyes on PMMA core surface are discussed. A pH-sensitive fluorescent dye, fluoresceinamine, and an O2-sensitive phosphorescent dye, Ru(dpp) both are successfully deposited using Si-adhesive gel-based as well as HydroThane-based deposition methods. Two different types of pH-sensors using two different techniques of depositing fluoresceinamine are demonstrated. Also, the effect of concentration of fluoresceinamine-dye molecules

  10. Troubling Metaphors and International Student Adjustment: Reflections from a Transnational Place

    Science.gov (United States)

    Starr-Glass, David

    2017-01-01

    On many campuses, offices of International Student Affairs address the perceived needs of international students. However, a number of underlying assumptions and persistent metaphors shape these efforts and influence their outcomes. All students are uniquely different and face equally different challenges in adjusting to higher education. Labeling…

  11. Living and Learning Internationally for a Viable Future: Reflecting on UNESCO CONFINTEA VI

    Science.gov (United States)

    Henschke, John A.

    2012-01-01

    International travel has the potential to expand one's learning horizons exponentially, especially with the abundantly enriching experiences of adult, continuing, and lifelong learning conferences. CONFINTEA VI (The Sixth World International Conference in Adult Education) sponsored by the United Nations Educational, Scientific, and Cultural…

  12. Education for International Mindedness: Life History Reflections on Schooling and the Shaping of a Cosmopolitan Outlook

    Science.gov (United States)

    Wright, Katie; Buchanan, Emma

    2017-01-01

    The development of "international mindedness" is an established aim of international education and has recently gained prominence in national school systems. Despite its increasing salience, it remains an ambiguous construct and an understudied aspect of schooling. It is implicated in globalized educational markets and attempts to…

  13. Reflections and Experiences of Student Paramedics Undertaking International Work-Integrated Learning Placements

    Science.gov (United States)

    Simpson, Paul; Thyer, Liz; Van Nugteren, Ben; Mitchell, Glen; Werner, Sarah

    2016-01-01

    International work-integrated learning (WIL) is increasingly common in health-related programs in Australian universities. Paramedicine programs are beginning to explore international WIL in line with the globalization of paramedicine as a profession and the national higher education emphasis on outward bound learning experiences. Using…

  14. Interns reflect: the effect of formative assessment with feedback during pre-internship

    Directory of Open Access Journals (Sweden)

    McKenzie S

    2017-01-01

    Full Text Available Susan McKenzie,1 Annette Burgess,2 Craig Mellis1 1Central Clinical School, 2Education Office, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia Background: It is widely known that the opportunity for medical students to be observed and to receive feedback on their procedural skills performance is variable in the senior years. To address this problem, we provided our Pre-Intern (PrInt students with “one-to-one” formative feedback on their ability to perform urethral catheterization (U/C and hypothesized that their future practice of U/C as interns would benefit. This study sought to evaluate the performance and practice of interns in U/C 4–5 months after having received feedback on their performance of U/C as PrInt students.Methods: Between 2013 and 2014, two cohorts of interns, (total n=66 who had received recent formative feedback on their U/C performance as PrInt students at Central Clinical School, were invited to complete an anonymous survey. The survey contained nine closed unvalidated questions and one open-ended question, designed to allow interns to report on their current practice of U/C.Results: Forty-one out of 66 interns (62% completed the survey. Thirty-five out of 41 respondents (85% reported that the assessment with feedback during their PrInt term was beneficial to their practice. Thirty of 41 (73% reported being confident to perform U/C independently. Eleven out of 41 respondents (27% reported that they had received additional training at intern orientation. Nine of the 11 interns (82% reported that they had a small, but a significant, increase in confidence to perform U/C when compared with the 30 of the 41 respondents (73% who had not (p=0.03.Conclusion: Our results substantiate our hypothesis that further education by assessment with feedback in U/C during PrInt was of benefit to interns’ performance. Additional educational reinforcement in U/C during intern orientation further improved intern

  15. Internal architecture of coffin-shaped ZSM-5 zeolite crystals with hourglass contrast unravelled by focused ion beam-assisted transmission electron microscopy.

    Science.gov (United States)

    Lu, J; Bartholomeeusen, E; Sels, B F; Schryvers, D

    2017-01-01

    Optical microscopy, focused ion beam and transmission electron microscopy are combined to study the internal architecture in a coffin-shaped ZSM-5 crystal showing an hourglass contrast in optical microscopy. Based on parallel lamellas from different positions in the crystal, the orientation relationships between the intergrowth components of the crystal are studied and the internal architecture and growth mechanism are illustrated. The crystal is found to contain two pyramid-like components aside from a central component. Both pyramid-like components are rotated by 90° along the common c-axis and with respect to the central component while the interfaces between the components show local zig-zag feature, the latter indicating variations in relative growth velocity of the two components. The pyramid-like intergrowth components are larger and come closer to one another in the middle of the crystal than at the edges, but they do not connect. A model of multisite nucleation and growth of 90° intergrowth components is proposed. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

  16. Reflections on Teaching Research Ethics in Education for International Postgraduate Students in the UK

    Science.gov (United States)

    Smith, Jan

    2016-01-01

    Research ethics in education is a challenging topic to teach and to learn. As the staff and student body in UK higher education and elsewhere diversifies, the challenges increase as shared reference points diminish. My teaching reflections focus on a key tension explored in this article: how the imperative of internationalising the curriculum…

  17. Comparative Education and Research Capacity Building: Reflections on International Transfer and the Significance of Context

    Directory of Open Access Journals (Sweden)

    Michael Crossley

    2012-04-01

    Full Text Available Recent years have seen a resurgence of interest in comparative and international education, along with a fundamental reconceptualisation of this distinctive multidisciplinary field of study. The nature and significance of these developments are explored with particular reference to their implications for broader research capacity building initiatives worldwide. In doing so, a critique of the international transfer of globally dominant research modalities and strategies is presented--along with arguments for increased attention to context sensitivity in both international development cooperation and educational research in general. Illustrative examples that support these arguments are drawn from the author's own research, from an analysis of emergent educational policy debates in the UK, and from related studies being carried out in Malaysia. In concluding, the strategic role of comparative research traditions and perspectives in a rapidly globalizing world is highlighted, while supporting the promotion of new initiative and research centres for comparative and international education.

  18. Reflections between CSR and international human rights in EU initiatives for a competitive inclusive society

    DEFF Research Database (Denmark)

    Buhmann, Karin

    : The paper aims to contribute to our understanding of whether a shift is taking place in societal attitudes towards a perception that corporations have duties based on international law. This is assessed on the basis of EU initiatives on inclusiveness and responsible competitiveness, particularly...... the EU Multistakeholder Forum and the Lisbon Strategy, with a particular focus on goals or views related to the human rights of non-discrimination and rights to work, education and vocational training, and network governance in (soft) law creation. It is found that despite obvious links, international...... law does not serve as a clear source of inclusiveness or responsible competitiveness. It is also found that the initiatives assessed do not indicate a shift at EU institutional level towards a perception that business holds duties under international law. International law seems at the most to be seen...

  19. Troubling Metaphors and International Student Adjustment: Reflections from a Transnational Place

    OpenAIRE

    David Starr-Glass

    2017-01-01

    On many campuses, offices of International Student Affairs address the perceived needs of international students. However, a number of underlying assumptions and persistent metaphors shape these efforts and influence their outcomes. All students are uniquely different and face equally different challenges in adjusting to higher education. Labeling students “international” may make institutional sense, but it can potentially hinder their transition, adjustment, and ultimate success. Applying r...

  20. Access to health care as a human right in international policy: critical reflections and contemporary challenges.

    Science.gov (United States)

    Castillo, Camilo Hernán Manchola; Garrafa, Volnei; Cunha, Thiago; Hellmann, Fernando

    2017-07-01

    Using the United Nations (UN) and its subordinate body, the World Health Organization (WHO), as a frame of reference, this article explores access to healthcare as a human right in international intergovernmental policies. First, we look at how the theme of health is treated within the UN, focusing on the concept of global health. We then discuss the concept of global health from a human rights perspective and go on to outline the debate surrounding universal coverage versus universal access as a human right, addressing some important ethical questions. Thereafter, we discuss universal coverage versus universal access using the critical and constructivist theories of international relations as a frame of reference. Finally, it is concluded that, faced with the persistence of huge global health inequalities, the WHO began to reshape itself, leaving behind the notion of health as a human right and imposing the challenge of reducing the wide gap that separates international intergovernmental laws from reality.

  1. International migration and the global agenda: reflections on the 1998 UN Technical Symposium.

    Science.gov (United States)

    Castles, S

    1999-01-01

    This article reviews the nature of discussions at the 1998 UN Technical Symposium on International Migration and Development. The Symposium reviewed the literature linking migration and development and successful policy approaches. Several themes emerged. A research framework is needed for accounting for all types of population mobility at all stages of the migratory process. Research should integrate contributions from a range of disciplines. The influence of social networks and cultural capital has grown in importance. Strategies need to account for women's experiences, which involve both empowerment and exploitation. Strategies need to consider return migration and better public information on migration and settlement. It was agreed that there is a need for a variety of quantitative and qualitative approaches and multidimensional analysis. The links between migration and development are complex, but sufficient information is available to greatly improve policy formation and international cooperation. National level responses have occasionally eroded the rights and protection of migrants. Few countries have adopted the 1990 UN Convention on the Rights of Migrant Workers and their Families and ILO Conventions 97 and 143. A prominent realization was that international cooperation did matter. International migration should be viewed as an opportunity for cooperation and development.

  2. Improving adolescent sexual and reproductive health in Latin America: reflections from an International Congress

    NARCIS (Netherlands)

    Córdova Pozo, K.; Chandra-Mouli, V.; Decat, P.; Nelson, E.; de Meyer, S.; Jaruseviciene, L.; Vega, B.; Segura, Z.; Auquilla, N.; Hagens, A.; van Braeckel, D.; Michielsen, K.

    2015-01-01

    In February 2014, an international congress on Promoting Adolescent Sexual and Reproductive Health (ASRH) took place in Cuenca, Ecuador. Its objective was to share evidence on effective ASRH intervention projects and programs in Latin America, and to link this evidence to ASRH policy and program

  3. Improving International Marketing Programs to Reflect Global Complexity and Risk: Curriculum Drivers and Constraints

    Science.gov (United States)

    Vos, Lynn

    2013-01-01

    This article looks at the curriculum redesign of a master's-level program in international marketing from a UK perspective. In order to ensure that the program would be more fit-for-purpose for future managers working under conditions of complexity, uncertainty, and within regimes often very different from the home market, the team began the…

  4. [Reflections on the concept of communication: second international goal of patient safety].

    Science.gov (United States)

    Medrano-Mariscal, Joel

    2015-01-01

    Effective communication is an element of prime importance, especially as it relates to health professional staff. Reflect on the concept and its meaning in a specific sector, taking into account their cultural and socio-environmental, requires interdisciplinary assistance in this case tools of medical anthropology as the emic view retake and construction of indicators are proposed. Medical anthropology and other social sciences, shows that the emic communication approach transcends the individual; so it is important to emphasize that communication has to be understood as a social construction, which helps to achieve understanding between people. Only from understanding the other will be able to think of an effective communication between health professionals.

  5. After Fukushima? On the educational and learning theoretical reflection of nuclear disasters. International perspectives

    International Nuclear Information System (INIS)

    Wigger, Lothar; Buenger, Carsten

    2017-01-01

    The book on the educational and learning theoretical reflection of nuclear disasters as a consequence of Fukushima includes contributions on the following issues: pedagogical approach: children write on Fukushima, description of the reality as pedagogical challenge; lessons learned on the nuclear technology - perspectives and limits of pedagogical evaluation: moral education - Japanese teaching materials, educational challenges at the universities with respect to nuclear technology and technology impact assessment; education and technology - questions concerning the pedagogical responsibility: considerations on the responsibility of scientists, on the discrepancy between technology and education, disempowerment of the public by structural corruption - nuclear disaster and post-democratic tendencies in Japan.

  6. Developing international open science collaborations: Funder reflections on the Open Science Prize.

    Science.gov (United States)

    Kittrie, Elizabeth; Atienza, Audie A; Kiley, Robert; Carr, David; MacFarlane, Aki; Pai, Vinay; Couch, Jennifer; Bajkowski, Jared; Bonner, Joseph F; Mietchen, Daniel; Bourne, Philip E

    2017-08-01

    The Open Science Prize was established with the following objectives: first, to encourage the crowdsourcing of open data to make breakthroughs that are of biomedical significance; second, to illustrate that funders can indeed work together when scientific interests are aligned; and finally, to encourage international collaboration between investigators with the intent of achieving important innovations that would not be possible otherwise. The process for running the competition and the successes and challenges that arose are presented.

  7. Comparison of two methods of preparation of tissue to study the internal anatomy of the delphacid Togosodes orizicolus with microscopy of electronic light

    International Nuclear Information System (INIS)

    Macaya-Lizano, A.V.; Pereira, R.; Espinoza, A.M.

    1997-01-01

    Two methods of embedding, sectioning and staining were developed to study the internal anatomy of delphacid plant hopper Tagosodes orizicolus, one of the most important plagues of rice in Latin America and the only vector of the white leaf tenuivirus (RHBV), using both light and electron microscopy. The paraffines-hematoxyline-eosin Y method allows color identification of tissues, for example purple for fat tissue, pink for muscles, yellow-brown for exocutile, while the resin-toluidine-blue method preserves better the ultrastructure but do not permit color identification. The information obtained by these procedures is complementary and the material can also be used for in situ studies by immuno microscopy, to assess the changes in cell ultrastructure and the localization and replication of the RHBV during its infection cycle in the insect vector. (author) [es

  8. International competence and knowledge studies and attitudes of the Brazilian Management accountant: analyses and reflections

    Directory of Open Access Journals (Sweden)

    Ricardo Lopes Cardoso

    2010-01-01

    Full Text Available The main purpose of this study is to understand what the competences of the Management accountant are, compare to international studies and assess the existence of competences to be prioritized. This questioning has as motivation the placements of Hardern (1995, Morgan (1997, IMA (1996 e 1999 and IFAC (2003. The theoretical basis about competences is related to McClelland study (1973, 1998, Boyatzis (1982 and Spencer and Spencer (1993. This research is based on the study of 18 competences about knowledge, skills and attitudes obtained in accountant literature and that have been submitted to 200 Management accountants. Data collection instrument presented a 0.884 Cronbach Alpha. From a factorial analysis and after Kruskal-Wallis test 12 competences were obtained as the most relevant segregated in 3 factors, in comparison to international studies of nine common competences 4 were not considered relevant in statistical tests and only one must be prioritized. Results demonstrate differences between competences required from Brazilian Management accountants and from other countries, being that their reasons is an open-ended question up to the moment.

  9. Indigenous Storytelling and Participatory Action Research: Allies Toward Decolonization? Reflections From the Peoples' International Health Tribunal.

    Science.gov (United States)

    Caxaj, C Susana

    2015-01-01

    Storytelling, in its various forms, has often been described as a practice with great emancipatory potential. In turn, Indigenous knowledge shows great promise in guiding a participatory action research (PAR) methodology. Yet these two approaches are rarely discussed in relation to one another, nor, has much been written in terms of how these two approaches may work synergistically toward a decolonizing research approach. In this article, I report on a community-driven knowledge translation activity, the Peoples' International Health Tribunal, as an exemplar of how narrative and PAR approaches, guided by local Indigenous knowledge, have great potential to build methodologically and ethically robust research processes. Implications for building globally relevant research alliances and scholarship are further discussed, particularly in relation to working with Indigenous communities.

  10. Is law failing to address air pollution? Reflections on international and EU developments.

    Science.gov (United States)

    Yamineva, Yulia; Romppanen, Seita

    2017-11-01

    Air pollution is a major global environmental problem, with various adverse effects on health and the environment. This introductory article provides an overview of related global and regional legal instruments. The article evaluates the legal landscape in terms of its coverage, geographic scope and effectiveness, and concludes that the legal measures currently in place fall far short of providing an adequate response to the problem of air pollution. Thus, there is a clear need to strengthen global and regional cooperation to improve air quality. Such cooperation is likely to take non-binding and flexible forms and involve both wider participation among States and broader engagement of various stakeholders. The informal character of cooperation also makes it possible to experiment with new governance approaches that are difficult to implement within the context of traditional international law.

  11. The International Association of Hydrogeologists (IAH): reflecting on 60 years of contributions to groundwater science and water management

    Science.gov (United States)

    Struckmeier, Willi; Howard, Ken; Chilton, John

    2016-08-01

    The 60th anniversary of the founding of the International Association of Hydrogeologists (IAH) is an important milestone that allows pause for reflection on how the association has evolved over the years and the contributions it has made to groundwater science and water management. IAH was founded in 1956 at the 20th International Geological Congress and developed rapidly during the 1980s and 1990s in response to a growing global interest in groundwater mapping and in sound approaches to resource protection and sustainable aquifer management. Incorporated in 2000, IAH has now secured its position as the world's leading international association specialising in groundwater with over 4,100 members in 131 countries. Much credit for this success must go to members, past and present, whose individual efforts and collaboration with sister institutions are documented here. These members have shaped the association's goals and contributed selflessly to its scientific programmes, publications and educational and charitable activities. Looking ahead to the next 60 years, it is essential that IAH does not rest on past achievements but listens and adjusts to the needs of members while continuing to pursue its mission of furthering the understanding, wise use and protection of groundwater resources throughout the world.

  12. 'How would you call this in English?' : Being reflective about translations in international, cross-cultural qualitative research.

    Science.gov (United States)

    Helmich, Esther; Cristancho, Sayra; Diachun, Laura; Lingard, Lorelei

    2017-04-01

    Medical education researchers increasingly collaborate in international teams, collecting data in different languages and from different parts of the world, and then disseminating them in English-language journals. Although this requires an ever-present need to translate, it often occurs uncritically. With this paper we aim to enhance researchers' awareness and reflexivity regarding translations in qualitative research. In an international study, we carried out interviews in both Dutch and English. To enable joint data analysis, we translated Dutch data into English, making choices regarding when and how to translate. In an iterative process, we contextualized our experiences, building on the social sciences and general health literature about cross-language/cross-cultural research. We identified three specific translation challenges: attending to grammar or syntax differences, grappling with metaphor, and capturing semantic or sociolinguistic nuances. Literature findings informed our decisions regarding the validity of translations, translating in different stages of the research process, coding in different languages, and providing 'ugly' translations in published research reports. The lessons learnt were threefold. First, most researchers, including ourselves, do not consciously attend to translations taking place in international qualitative research. Second, translation challenges arise not only from differences in language, but also from cultural or societal differences. Third, by being reflective about translations, we found meaningful differences, even between settings with many cultural and societal similarities. This conscious process of negotiating translations was enriching. We recommend researchers to be more conscious and transparent about their translation strategies, to enhance the trustworthiness and quality of their work.

  13. Fast Focal Point Correction in Prism-Coupled Total Internal Reflection Scanning Imager Using an Electronically Tunable Lens.

    Science.gov (United States)

    Zhu, Chenggang; Ge, Bilin; Chen, Ru; Zhu, Xiangdong; Mi, Lan; Ma, Jiong; Wang, Xu; Zheng, Fengyun; Fei, Yiyan

    2018-02-09

    Total internal reflection (TIR) is useful for interrogating physical and chemical processes that occur at the interface between two transparent media. Yet prism-coupled TIR imaging microscopes suffer from limited sensing areas due to the fact that the interface (the object plane) is not perpendicular to the optical axis of the microscope. In this paper, we show that an electrically tunable lens can be used to rapidly and reproducibly correct the focal length of an oblique-incidence scanning microscope (OI-RD) in a prism-coupled TIR geometry. We demonstrate the performance of such a correction by acquiring an image of a protein microarray over a scan area of 4 cm² with an effective resolution of less than 20 microns. The electronic focal length tuning eliminates the mechanical movement of the illumination lens in the scanning microscope and in turn the noise and background drift associated with the motion.

  14. Fast Focal Point Correction in Prism-Coupled Total Internal Reflection Scanning Imager Using an Electronically Tunable Lens

    Directory of Open Access Journals (Sweden)

    Chenggang Zhu

    2018-02-01

    Full Text Available Total internal reflection (TIR is useful for interrogating physical and chemical processes that occur at the interface between two transparent media. Yet prism-coupled TIR imaging microscopes suffer from limited sensing areas due to the fact that the interface (the object plane is not perpendicular to the optical axis of the microscope. In this paper, we show that an electrically tunable lens can be used to rapidly and reproducibly correct the focal length of an oblique-incidence scanning microscope (OI-RD in a prism-coupled TIR geometry. We demonstrate the performance of such a correction by acquiring an image of a protein microarray over a scan area of 4 cm2 with an effective resolution of less than 20 microns. The electronic focal length tuning eliminates the mechanical movement of the illumination lens in the scanning microscope and in turn the noise and background drift associated with the motion.

  15. Absence of Fungal Spore Internalization by Bronchial Epithelium in Mouse Models Evidenced by a New Bioimaging Approach and Transmission Electronic Microscopy.

    Science.gov (United States)

    Rammaert, Blandine; Jouvion, Grégory; de Chaumont, Fabrice; Garcia-Hermoso, Dea; Szczepaniak, Claire; Renaudat, Charlotte; Olivo-Marin, Jean-Christophe; Chrétien, Fabrice; Dromer, Françoise; Bretagne, Stéphane

    2015-09-01

    Clinical data and experimental studies suggest that bronchial epithelium could serve as a portal of entry for invasive fungal infections. We therefore analyzed the interactions between molds and the bronchial/bronchiolar epithelium at the early steps after inhalation. We developed invasive aspergillosis (Aspergillus fumigatus) and mucormycosis (Lichtheimia corymbifera) murine models that mimic the main clinical risk factors for these infections. Histopathology studies were completed with a specific computer-assisted morphometric method to quantify bronchial and alveolar spores and with transmission electron microscopy. Morphometric analysis revealed a higher number of bronchial/bronchiolar spores for A. fumigatus than L. corymbifera. The bronchial/bronchiolar spores decreased between 1 and 18 hours after inoculation for both fungi, except in corticosteroid-treated mice infected with A. fumigatus, suggesting an effect of cortisone on bronchial spore clearance. No increase in the number of spores of any species was observed over time at the basal pole of the epithelium, suggesting the lack of transepithelial crossing. Transmission electron microscopy did not show spore internalization by bronchial epithelial cells. Instead, spores were phagocytized by mononuclear cells on the apical pole of epithelial cells. Early epithelial internalization of fungal spores in vivo cannot explain the bronchial/bronchiolar epithelium invasion observed in some invasive mold infections. The bioimaging approach provides a useful means to accurately enumerate and localize the fungal spores in the pulmonary tissues. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  16. Electron Microscopy.

    Science.gov (United States)

    Beer, Michael

    1980-01-01

    Reviews technical aspects of structure determination in biological electron microscopy (EM). Discusses low dose EM, low temperature microscopy, electron energy loss spectra, determination of mass or molecular weight, and EM of labeled systems. Cites 34 references. (CS)

  17. The Micromorphological Research of the Internal Structure of Chairside CAD/CAM Materials by the Method of Scanning Impulse Acoustic Microscopy (SIAM).

    Science.gov (United States)

    Goryainova, Kristina E; Morokov, Egor S; Retinskaja, Marina V; Rusanov, Fedor S; Apresyan, Samvel V; Lebedenko, Igor Yu

    2018-01-01

    The aim of the present work was to compare the elastic properties and internal structure of 4 different CAD/CAM chairside materials, by the method of Scanning Impulse Acoustic Microscopy (SIAM). Four chairside CAD/CAM materials with different structures from hybrid ceramic (VITA Enamic, VITA Zahnfabrik), feldspatic ceramic (VITABlocs Mark II, VITA Zahnfabrik), leucite glass-ceramic (IPS Empress CAD, Ivoclar Vivadent) and PMMA (Telio CAD, Ivoclar Vivadent) were examined by Scanning Impulse Acoustic Microscope (SIAM). The results of micromorphological research of CAD/CAM chairside materials using SIAM method showed differences between the internal structures of these materials. The internal structure of feldspatic and glass-ceramic samples revealed the presence of pores with different sizes, from 10 to 100 microns; the structure of polymer materials rendered some isolated defects, while in the structure of hybrid material, defects were not found. Based on the results obtained from the present study, in cases of chairside production of dental crowns, it would be advisable to give preference to the blocks of hybrid ceramics. Such ceramics devoid of quite large porosity, glazing for CAD/CAM crowns made from leucite glass-ceramic and feldspatic ceramic may be an option. For these purposes, commercially available special muffle furnace for clinical and laboratory individualization and glazing of ceramic prostheses were provided. Further studies are needed to confirm the evidence emerging from the present research.

  18. Measurement of the Indentation Modulus and the Local Internal Friction in Amorphous SiO2 Using Atomic Force Acoustic Microscopy

    Directory of Open Access Journals (Sweden)

    Zhang B.

    2016-03-01

    Full Text Available For the past two decades, atomic force acoustic microscopy (AFAM, an advanced scanning probe microscopy technique, has played a promising role in materials characterization with a good lateral resolution at micro/nano dimensions. AFAM is based on inducing out-of-plane vibrations in the specimen, which are generated by an ultrasonic transducer. The vibrations are sensed by the AFM cantilever when its tip is in contact with the material under test. From the cantilver’s contactresonance spectra, one determines the real and the imaginary part of the contact stiffness k*, and then from these two quantities the local indentation modulus M' and the local damping factor Qloc-1 can be obtained with a spatial resolution of less than 10 nm. Here, we present measured data of M' and of Qloc-1 for the insulating amorphous material, a-SiO2. The amorphous SiO2 layer was prepared on a crystalline Si wafer by means of thermal oxidation. There is a spatial distribution of the indentation modulus M' and of the internal friction Qloc-1. This is a consequence of the potential energy landscape for amorphous materials.

  19. In vivo characterization of mechanical tissue properties of internal organs using endoscopic microscopy and inverse finite element analysis.

    Science.gov (United States)

    Schwenninger, David; Schumann, Stefan; Guttmann, Josef

    2011-02-03

    Knowledge about mechanical tissue properties is required for functional modelling and simulating of tissue and organ responses to external mechanical stress. To get the right properties especially for functional modelling of organs, tissue properties have to be determined in vivo. There are only few described methods for characterization of internal organ's tissue mechanics that can be applied in vivo. We introduce and evaluate a method to determine mechanical tissue properties, especially those of lung tissue, endoscopically. Inverse finite element analysis (utilizing a Neo-Hookean model for hyperelastic materials) and image processing algorithms are used to determine the shear modulus of a soft tissue. The resulting values for shear moduli were normally distributed. The shear modulus of the artificial tissue sample was determined with a relative error of 0.47% compared to the value obtained by uniaxial tensile test. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Using the Light Microscopy Module (LMM) on the International Space Station (ISS), The Advanced Colloids Experiment (ACE) and MacroMolecular Biophysics (MMB)

    Science.gov (United States)

    Meyer, William; Foster, William M.; Motil, Brian J.; Sicker, Ronald; Abbott-Hearn, Amber; Chao, David; Chiaramonte, Fran; Atherton, Arthur; Beltram, Alexander; Bodzioney, Christopher M.; hide

    2016-01-01

    The Light Microscopy Module (LMM) was launched to the International Space Station (ISS) in 2009 and began science operations in 2010. It continues to support Physical and Biological scientific research on ISS. During 2016, if all goes as planned, three experiments will be completed: [1] Advanced Colloids Experiments with Heated base-2 (ACE-H2) and [2] Advanced Colloids Experiments with Temperature control (ACE-T1). Preliminary results, along with an overview of present and future LMM capabilities will be presented; this includes details on the planned data imaging processing and storage system, along with the confocal upgrade to the core microscope. [1] a consortium of universities from the State of Kentucky working through the Experimental Program to Stimulate Competitive Research (EPSCoR): Stuart Williams, Gerold Willing, Hemali Rathnayake, et al. and [2] from Chungnam National University, Daejeon, S. Korea: Chang-Soo Lee, et al.

  1. Changes in hemp secondary fiber production related to technical fiber variability revealed by light microscopy and attenuated total reflectance Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Fernandez-Tendero, Eva; Day, Arnaud; Legros, Sandrine; Habrant, Anouck; Hawkins, Simon; Chabbert, Brigitte

    2017-01-01

    Interest in hemp (Cannabis sativa L.) is increasing due to the development of a new range of industrial applications based on bast fibers. However the variability of bast fiber yield and quality represents an important barrier to further exploitation. Primary and secondary fiber content was examined in two commercial hemp varieties (Fedora 17, Santhica 27) grown under contrasted sowing density and irrigation conditions. Both growing conditions and hemp varieties impact stem tissue architecture with a large effect on the proportion of secondary fibers but not primary fibers. Attenuated total reflectance infrared spectroscopy allowed the discrimination of manually-isolated native primary fibers and secondary fibers but did not reveal any clustering according to growing conditions and variety. Infrared data were confirmed by wet chemistry analyses that revealed slight but significant differences between primary and secondary fiber cell wall composition. Infrared spectroscopy of technical fibers obtained after mechanical defibering revealed differences with native primary, but not secondary fibers and also discriminated samples obtained from plants grown under different conditions. Altogether the results suggested that the observed variability of hemp technical fibers could be partially explained by i) differences in secondary fiber production and ii) differential behavior during mechanical defibering resulting in unequal separation of primary and secondary fibers.

  2. Observation Platform for Dynamic Biomedical and Biotechnology Experiments Using the International Space Station (ISS) Light Microscopy Module (LMM)

    Science.gov (United States)

    Kurk, Michael A. (Andy)

    2015-01-01

    Techshot, Inc., has developed an observation platform for the LMM on the ISS that will enable biomedical and biotechnology experiments. The LMM Dynamic Stage consists of an electronics module and the first two of a planned suite of experiment modules. Specimens and reagent solutions can be injected into a small, hollow microscope slide-the heart of the innovation-via a combination of small reservoirs, pumps, and valves. A life science experiment module allows investigators to load up to two different fluids for on-orbit, real-time image cytometry. Fluids can be changed to initiate a process, fix biological samples, or retrieve suspended cells. A colloid science experiment module conducts microparticle and nanoparticle tests for investigation of colloid self-assembly phenomena. This module includes a hollow glass slide and heating elements for the creation of a thermal gradient from one end of the slide to the other. The electronics module supports both experiment modules and contains a unique illuminator/condenser for bright and dark field and phase contrast illumination, power supplies for two piezoelectric pumps, and controller boards for pumps and valves. This observation platform safely contains internal fluids and will greatly accelerate the research and development (R&D) cycle of numerous experiments, products, and services aboard the ISS.

  3. Planar solar concentrator featuring alignment-free total-internal-reflection collectors and an innovative compound tracker.

    Science.gov (United States)

    Teng, Tun-Chien; Lai, Wei-Che

    2014-12-15

    This study proposed a planar solar concentrator featuring alignment-free total-internal-reflection (TIR) collectors and an innovative compound tracker. The compound tracker, combining a mechanical single-axis tracker and scrollable prism sheets, can achieve a performance on a par with dual-axis tracking while reducing the cost of the tracking system and increasing its robustness. The alignment-free TIR collectors are assembled on the waveguide without requiring alignment, so the planar concentrator is relatively easily manufactured and markedly increases the feasibility for use in large concentrators. Further, the identical TIR collector is applicable to various-sized waveguide slab without requiring modification, which facilitates flexibility regarding the size of the waveguide slab. In the simulation model, the thickness of the slab was 2 mm, and its maximal length reached 6 m. With an average angular tolerance of ±0.6°, and after considering both the Fresnel loss and the angular spread of the sun, the simulation indicates that the waveguide concentrator of a 1000-mm length provides the optical efficiencies of 62-77% at the irradiance concentrations of 387-688, and the one of a 2000-mm length provides the optical efficiencies of 52-64.5% at the irradiance concentrations of 645-1148. Alternatively, if a 100-mm horizontally staggered waveguide slab is collocated with the alignment-free TIR collectors, the optical efficiency would be greatly improved up to 91.5% at an irradiance concentration of 1098 (C(geo) = 1200X).

  4. Real time study of amalgam formation and mercury adsorption on thin gold film by total internal reflection ellipsometry

    Science.gov (United States)

    Paulauskas, A.; Selskis, A.; Bukauskas, V.; Vaicikauskas, V.; Ramanavicius, A.; Balevicius, Z.

    2018-01-01

    Total internal reflection ellipsometry (TIRE) was utilized in its dynamic data acquisition mode to reveal the percentage of mercury present in an amalgam surface layer. In determining the optical constants of the amalgam film, the non-homogeneities of the formed surface layer were taken into account. The composition of the amalgam layer by percentage was determined using the EMA Bruggemann model for the analysis of the TIRE data. Regression results showed that amalgam layer consisted of mercury 16.00 ± 0.43% and gold 84.00 ± 0.43%. This real time TIRE analysis has shown that for these studies method can detect 0.6 ± 0.4% of mercury on a gold surface, proving that this is a suitable optical technique for obtaining real time readouts. The structural analysis of SEM and AFM have shown that the amalgam layer had a dendritic structure, which formation was determined by the weak adhesion of the gold atoms onto its surface.

  5. The Advantages of an Attenuated Total Internal Reflection Infrared Microspectroscopic Imaging Technique for the Analysis of Polymer Laminates.

    Science.gov (United States)

    Ling, Chen; Sommer, André J

    2015-06-01

    Until recently, the analysis of polymer laminates using infrared microspectroscopy involved the painstaking separation of individual layers by dissection or by obtaining micrometer thin cross-sections. The latter usually requires the expertise of an individual trained in microtomy and even then, the very structure of the laminate could affect the outcome of the spectral results. The recent development of attenuated total internal reflection (ATR) infrared microspectroscopy imaging has provided a new avenue for the analysis of these multilayer structures. This report compares ATR infrared microspectroscopy imaging with conventional transmission infrared microspectroscopy imaging. The results demonstrate that the ATR method offers improved spatial resolution, eliminates a variety of competing optical processes, and requires minimal sample preparation relative to transmission measurements. These advantages were illustrated using a polymer laminate consisting of 11 different layers whose thickness ranged in size from 4-20 μm. The spatial resolution achieved by using an ATR-FTIR (Fourier transform infrared spectroscopy) imaging technique was diffraction limited. Contrast in the ATR images was enhanced by principal component analysis.

  6. Studying flow close to an interface by total internal reflection fluorescence cross-correlation spectroscopy: Quantitative data analysis

    Science.gov (United States)

    Schmitz, R.; Yordanov, S.; Butt, H. J.; Koynov, K.; Dünweg, B.

    2011-12-01

    Total internal reflection fluorescence cross-correlation spectroscopy (TIR-FCCS) has recently [S. Yordanov , Optics ExpressOPEXFF1094-408710.1364/OE.17.021149 17, 21149 (2009)] been established as an experimental method to probe hydrodynamic flows near surfaces, on length scales of tens of nanometers. Its main advantage is that fluorescence occurs only for tracer particles close to the surface, thus resulting in high sensitivity. However, the measured correlation functions provide only rather indirect information about the flow parameters of interest, such as the shear rate and the slip length. In the present paper, we show how to combine detailed and fairly realistic theoretical modeling of the phenomena by Brownian dynamics simulations with accurate measurements of the correlation functions, in order to establish a quantitative method to retrieve the flow properties from the experiments. First, Brownian dynamics is used to sample highly accurate correlation functions for a fixed set of model parameters. Second, these parameters are varied systematically by means of an importance-sampling Monte Carlo procedure in order to fit the experiments. This provides the optimum parameter values together with their statistical error bars. The approach is well suited for massively parallel computers, which allows us to do the data analysis within moderate computing times. The method is applied to flow near a hydrophilic surface, where the slip length is observed to be smaller than 10nm, and, within the limitations of the experiments and the model, indistinguishable from zero.

  7. Confocal microscopy

    Indian Academy of Sciences (India)

    This is elucidated by time-resolved confocal microscopy. Keywords. Porphyrin; micro-rod; anisotropy; exciton coupling; confocal microscopy. 1. Introduction. Supra-molecular assemblies of porphyrin play a central role in light harvesting during photosynthesis.1 10 In such a system, the absorbed photon shuttles between dif-.

  8. Blogging as a tool to promote reflection among dietetic and physical therapy students during a multidisciplinary international service-learning experience.

    Science.gov (United States)

    Wright, Lauri; Lundy, Mary

    2012-01-01

    Service-learning is a guided, structured learning experience that engages students in service to a community for the mutual benefit of the student and community. There is a growing trend in healthcare to include international service-learning experiences in the training curriculum to promote cultural competence. A critical element of service-learning is reflection. There have been many research studies examining how best to support and facilitate the reflective thinking process in students. The purpose of this study was to assess the development of reflective thinking among graduate allied health students during an interdisciplinary international service-learning experience using a web-based collaborative blog. Twelve graduate students-six dietetic interns and six physical therapy doctoral students-traveled to Belize for 6 days to provide primary healthcare screenings and intervention to a community. Group blogging was found to be an effective tool to promote reflection in allied health student and short duration service-learning experience developed reflective thinking.

  9. Invited Article: An active terahertz polarization converter employing vanadium dioxide and a metal wire grating in total internal reflection geometry

    Science.gov (United States)

    Liu, Xudong; Chen, Xuequan; Parrott, Edward P. J.; Han, Chunrui; Humbert, Georges; Crunteanu, Aurelian; Pickwell-MacPherson, Emma

    2018-05-01

    Active broadband terahertz (THz) polarization manipulation devices are challenging to realize, but also of great demand in broadband terahertz systems. Vanadium dioxide (VO2) shows a promising phase transition for active control of THz waves and provides broadband polarization characteristics when integrated within grating-type structures. We creatively combine a VO2-based grating structure with a total internal reflection (TIR) geometry providing a novel interaction mechanism between the electromagnetic waves and the device, to realize a powerful active broadband THz polarization-controlling device. The device is based on a Si-substrate coated with a VO2 layer and a metal grating structure on top, attached to a prism for generating the TIR condition on the Si-VO2-grating interface. The grating is connected to electrodes for electrically switching the VO2 between its insulating and conducting phases. By properly selecting the incident angle of the THz waves, the grating direction, and the incident polarization state, we first achieved a broadband intensity modulator under a fused silica prism with an average modulation depth of 99.75% in the 0.2-1.1 THz region. Additionally, we realized an active ultra-broadband quarter-wave converter under a Si prism that can be switched between a 45° linear rotator and a quarter wave converter in the 0.8-1.5 THz region. This is the first demonstration of an active quarter-wave converter with ultra-broad bandwidth performance. Our work shows a highly flexible and multifunctional polarization-controlling device for broadband THz applications.

  10. Experimental and numerical studies of the scattering of light from a two-dimensional randomly rough interface in the presence of total internal reflection: optical Yoneda peaks.

    Science.gov (United States)

    González-Alcalde, Alma K; Banon, Jean-Philippe; Hetland, Øyvind S; Maradudin, Alexei A; Méndez, Eugenio R; Nordam, Tor; Simonsen, Ingve

    2016-11-14

    The scattering of polarized light from a dielectric film sandwiched between two different semi-infinite dielectric media is studied experimentally and theoretically. The illuminated interface is planar, while the back interface is a two-dimensional randomly rough interface. We consider here only the case in which the medium of incidence is optically more dense than the substrate, in which case effects due to the presence of a critical angle for total internal reflection occur. A reduced Rayleigh equation for the scattering amplitudes is solved by a rigorous, purely numerical, nonperturbative approach. The solutions are used to calculate the reflectivity of the structure and the mean differential reflection coefficient. Optical analogues of Yoneda peaks are present in the results obtained. The computational results are compared with experimental data for the in-plane mean differential reflection coefficient, and good agreement between theory and experiment is found.

  11. Using an Intention/Reflection Practice to Focus Students towards Future Professions in a Short-Term International Travel Experience

    Science.gov (United States)

    Fierke, Kerry K.; Lepp, Gardner A.; Bastianelli, Karen; Vogelsang, Lisa; Tornabene, Ladona

    2016-01-01

    The article describes a student-centered approach to generating meaningful learning outcomes in a short-term study abroad program. A practice named Intention/Reflection (I/R) was used to help students to identify, articulate, and reflect upon learning objectives that were personally meaningful, within the broader framework of the intended outcomes…

  12. Immunities of International Organizations before Domestic Courts : Reflections on the Collective Labour Case against the European Patent Organization

    NARCIS (Netherlands)

    Ryngaert, C.M.J.

    2016-01-01

    The Netherlands is home to a substantial number of international organizations, which on the basis of international agreements are entitled to immunity from jurisdiction and enforcement before Dutch courts. This immunity grant has not stopped claimants from suing international organizations in The

  13. Conceptual Reflections on Ethics for International Research Collaborations in Disaster Impacted Areas from the Experiences in Indonesia, New Zealand and Japan

    Directory of Open Access Journals (Sweden)

    Christopher Gomez

    2014-12-01

    Full Text Available The present contribution is by no means a first attempt at considering the ethics in human activities, interactions in disaster impacted areas, but it is more the case of looking at 'international research' that present a very particular difficulty for ethics: the notion of trans-boundary, multi-dimensional idea of one group not really belonging within another, but which will perform functions inside this second group and eventually alter, modify some of the original organs. This paper explain the reflections of the ethical consideration of international research collaboration in disaster impacted areas which are emerged from the experiences in Indonesia, New Zealand and Japan.

  14. Implementing the First Cross-border Professional Development Online Course through International E-mentoring: Reflections and Perspectives

    Directory of Open Access Journals (Sweden)

    Buddhini Gayathri Jayatilleke

    2017-03-01

    Full Text Available This research paper discusses the accomplishments, issues, and challenges experienced by Open University of Sri Lanka (OUSL academics when offering the first cross-border professional development online course to train online tutors and mentors. The course was delivered exclusively online and facilitated by OUSL academics and e-mentors from the USA. The course was comprised of 30 participants: 9 from Pakistan, 10 from Mauritius and 11 from Sri Lanka. This qualitative study is based on reflections of both faculty and participants. Data were collected using reflections and informal anecdotal records of the three OUSL academics and self-reflection instruments (pre, mid and final administered to participants, and reflective journal entries made by participants. Participants’ views were triangulated with the reflections of the OUSL academics to validate the results. While there were many accomplishments in the design and delivery of the course, the findings revealed that there were many challenges in implementing the course: pedagogical, organizational and technological aspects in particular. The paper provides recommendations to address such challenges when offering cross-border online courses in the future.

  15. Rethinking the Employability of International Graduate Migrants: Reflections on the Experiences of Zimbabweans with Degrees from England

    Science.gov (United States)

    McGrath, Simon; Madziva, Roda; Thondhlana, Juliet

    2017-01-01

    The last decade has seen the rise of literature focused on the rapid expansion of international students in higher education globally and the growing policy discourse around improving graduate employability. However, both, inevitably, have limitations. Together, they tend to homogenise international learners and see them narrowly as simply…

  16. Ethical principles in international nuclear trade and the role of international treaties and agreements in their implementation. Reflections on the future

    International Nuclear Information System (INIS)

    Cavalanti, C. de A.

    1992-01-01

    The growing importance of nuclear energy (on the threshold of the twenty-first century) and of its ethical uses is considered, including major political events in recent years, their social and economic consequences in the world scene. International Nuclear Law is seen as the most adequate instrument to promote the ethical uses of nuclear energy on a worldwide basis, so that mankind can benefit safely and properly and improving their living conditions in general. Problems associated with access to nuclear technology, plants, equipments and materials are addressed. Basic principles of international agreements ruling nuclear trade, ethical aspects are also covered. The different markets involved in international nuclear trade and their specific requirements are described. Certain international treaties on the peaceful uses of nuclear energy are discussed such as the Non-Proliferation Treaty and the Tlatelolco Treaty as are international conventions on matters related to the use of nuclear energy, such as the environment and protection of personnel. The author concludes by debating whether ethical uses of nuclear energy are a possible reality or merely utopia. Prospects on the future of international nuclear trade are considered. (author)

  17. College Athletes' Reflective Judgment: A Moderator between Sport and Sociocultural Pressures, Body Ideal Internalization, and Body Dissatisfaction

    Science.gov (United States)

    Greene, Catie A.

    2016-01-01

    The purpose of this research was to investigate the sociocultural model of eating disorder development among male and female college student-athletes as moderated by students' level of Reflective Judgment, a stage theory of adult epistemology marked by increasing cognitive complexity. A review of literature on the established relationships between…

  18. Photoacoustic Microscopy

    OpenAIRE

    Yao, Junjie; Wang, Lihong V.

    2013-01-01

    Photoacoustic microscopy (PAM) is a hybrid in vivo imaging technique that acoustically detects optical contrast via the photoacoustic effect. Unlike pure optical microscopic techniques, PAM takes advantage of the weak acoustic scattering in tissue and thus breaks through the optical diffusion limit (∼1 mm in soft tissue). With its excellent scalability, PAM can provide high-resolution images at desired maximum imaging depths up to a few millimeters. Compared with backscattering-based confocal...

  19. A tool for clinical reasoning and reflection using the international classification of functioning, disability and health (ICF) framework and patient management model.

    Science.gov (United States)

    Atkinson, Heather L; Nixon-Cave, Kim

    2011-03-01

    Professional development is a cornerstone of physical therapist practice. As the profession moves toward the ideals of Vision 2020, more emphasis is being placed on the process of clinical decision making. Although reflection and mentorship are widely regarded as important instruments to facilitate the progression of clinical reasoning skills, little guidance exists in the postprofessional arena to assist clinicians with these essential needs. As more organizations develop formal mentoring programs, a need arises for a tool that will engage mentors, protégés, and clinicians of all abilities in thoughtful reflection and discussion that will help develop clinical reasoning skills. The process of developing reflective clinical decision-making skills in physical therapist practitioners is described, and how this process was used at one institution is illustrated. A tool for clinical reasoning and reflection is proposed that incorporates the existing conceptual frameworks of the Guide to Physical Therapist Practice and the International Classification of Functioning, Disability and Health (ICF). This case report discusses how the tool was implemented by staff with varying levels of expertise, their outcomes in regard to the development of their clinical reasoning skills, and how the tool facilitated mentoring sessions around patient cases to improve care. This case report describes a practical application of a postprofessional educational process designed to develop reflective and patient-centered clinical reasoning skills. Although this process has shown some preliminary success, more research is warranted. By cultivating reflective thinking and critical inquiry, the physical therapy profession can help develop autonomous practitioners of physical therapy and promote the ideals of Vision 2020.

  20. Theoretical approach to surface plasmon scattering microscopy for single nanoparticle detection in near infrared region

    Science.gov (United States)

    Son, Taehwang; Kim, Donghyun

    2015-03-01

    We present a theoretical approach to single nanoparticle detection using surface plasmon scattering microscopy. Through rigorous coupled wave analysis assuming light incidence on a gold coated BK7 glass substrate under total internal reflection condition for a 200-nm polystyrene as targets attached to the gold film, it was found that surface plasmon polariton induced by incident light on the gold thin film is perturbed. As a result, parabolic waves were observed in the reflection plane. By varying angles of incidence and wavelengths, optimum incident conditions for surface plasmon scattering microscopy were obtained.

  1. Maximising Intercultural Learning in Short Term International Placements: Findings Associated with Orientation Programs, Guided Reflection and Immersion

    Science.gov (United States)

    Campbell, Coral J. L.; Walta, Caroline

    2015-01-01

    Short-term international practicum experience is now a feature of many university education programs in Australia in an attempt to engage students with the growing multi-cultural aspects of Australian life. The stated purposes of such practicum experiences generally highlight intercultural learning, which is associated with the development of…

  2. Standard Setting for Next Generation TOEFL Academic Speaking Test (TAST): Reflections on the ETS Panel of International Teaching Assistant Developers

    Science.gov (United States)

    Papajohn, Dean

    2006-01-01

    While many institutions have utilized TOEFL scores for international admissions for many years, a speaking section has never before been a required part of TOEFL until the development of the iBT/Next Generation TOEFL. So institutions will need to determine how to set standards for the speaking section of TOEFL, also known as TOEFL Academic…

  3. Capacity Building in Southern Africa: Experiences and Reflections--Towards Joint Knowledge Production and Social Change in International Development Cooperation

    Science.gov (United States)

    Zeelen, Jacques; van der Linden, Josje

    2009-01-01

    The intent of capacity building in international development cooperation is to enable people to control their own development. Important premises are ownership, choice and self-esteem. The authors analyse the dynamics of the enabling process in practice, based on their own experiences working for several years in universities in developing…

  4. Reflective practice and social responsibility in family medicine: Effect of performing an international rotation in a developing country.

    Science.gov (United States)

    Loignon, Christine; Gottin, Thomas; Valois, Carol; Couturier, François; Williams, Robert; Roy, Pierre-Michel

    2016-11-01

    To explore the perceived effect of an elective international health rotation on family medicine resident learning. Qualitative, collaborative study based on semistructured interviews. Quebec. A sample of 12 family medicine residents and 9 rotation supervisors (N = 21). Semistructured interviews of residents and rotation supervisors. Residents and supervisors alike reported that their technical skills and relationship skills had benefited. All increased their knowledge of tropical pathologies and learned to expand their clinical examinations. They benefited from having very rich interactions in other care settings, working with vulnerable populations. The rotations had their greatest effect on relationship skills (communication, empathy, etc) and the ability to work with vulnerable patients. All of the participants were exposed to local therapies and local interpretations of disease symptoms and pathogenesis. The findings of this study will have a considerable effect on pedagogy. The residents' experiences of their international health rotations and what they learned in terms of medical skills and pedagogic approaches in working with patients are described. Using a collaborative approach with the rotation supervisors, the data were triangulated and the benefits of an international rotation on academic training were more accurately defined. The findings can now be used to enrich academic programs in social and preventive medicine and more adequately prepare future family physicians for work in various social and cultural settings. Copyright© the College of Family Physicians of Canada.

  5. Use of total internal reflection Raman (TIR) and attenuated total reflection infrared (ATR-IR) spectroscopy to analyze component separation in thin offset ink films after setting on coated paper surfaces.

    Science.gov (United States)

    Kivioja, Antti; Hartus, Timo; Vuorinen, Tapani; Gane, Patrick; Jääskeläinen, Anna-Stiina

    2013-06-01

    The interactive behavior of ink constituents with porous substrates during and after the offset print process has an important effect on the quality of printed products. To help elucidate the distribution of ink components between the retained ink layer and the substrate, a variety of spectroscopic and microscopic analysis techniques have been developed. This paper describes for the first time the use of total internal reflection (TIR) Raman spectroscopy to analyze the penetration behavior of separated offset ink components (linseed oil, solid color pigment) in coated papers providing chemically intrinsic information rapidly, nondestructively, and with minimal sample preparation. In addition, the already widely applied technique of attenuated total reflection infrared spectroscopy (ATR-IR) was evaluated in parallel and compared. The results of the ATR-IR Raman clearly revealed an improvement in uppermost depth resolution compared with values previously published from other nondestructive techniques, and the method is shown to be capable of providing new knowledge of the setting of thin (0.25-2 μm) offset ink films, allowing the spreading and the penetration behavior on physically different paper coating surfaces to be studied.

  6. Silicon nitride waveguide platform for fluorescence microscopy of living cells.

    Science.gov (United States)

    Tinguely, Jean-Claude; Helle, Øystein Ivar; Ahluwalia, Balpreet Singh

    2017-10-30

    Waveguide chip-based microscopy reduces the complexity of total internal reflection fluorescence (TIRF) microscopy, and adds features like large field of view illumination, decoupling of illumination and collection path and easy multimodal imaging. However, for the technique to become widespread there is a need of low-loss and affordable waveguides made of high-refractive index material. Here, we develop and report a low-loss silicon nitride (Si 3 N 4 ) waveguide platform for multi-color TIRF microscopy. Single mode conditions at visible wavelengths (488-660 nm) were achieved using shallow rib geometry. To generate uniform excitation over appropriate dimensions waveguide bends were used to filter-out higher modes followed by adiabatic tapering. Si 3 N 4 material is finally shown to be biocompatible for growing and imaging living cells.

  7. An assessment of the importance ofexposure routes to the uptake and internal localisation of fluorescent nanoparticles in zebrafish (Danio rerio), using light sheet microscopy

    DEFF Research Database (Denmark)

    Skjolding, Lars Michael; Ašmonaitė, G; Jølck, Rasmus Irming

    2017-01-01

    A major challenge in nanoecotoxicology is finding suitable methods to determine the uptake and localisation of nanoparticles on a whole-organism level. Some uptake methods have been associated with artefacts induced by sample preparation, including staining for electron microscopy. This study used...... light sheet microscopy (LSM) to define the uptake and localisation of fluorescently labelled nanoparticles in living organisms with minimal sample preparation. Zebrafish (Danio rerio) were exposed to fluorescent gold nanoparticles (Au NPs) and fluorescent polystyrene NPs via aqueous or dietary exposure...

  8. Reflecting reflection in supervision

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    Reflection has moved from the margins to the mainstream in supervision. Notions of reflection have become well established since the late 1980s. These notions have provided useful framing devices to help conceptualize some important processes in guidance and counseling. However, some applications...... of these notions have distorted their original connotations and taken an excessively instrumentalistic and individualistic approach to their use. This paper will argue that we are, in the 2000s, seeing a questioning of an overly instrumentalistic and individualistic view of learning and development previously...... associated with reflection and an exploration of alternative conceptions that view reflection within the context of settings which have a more group- and team-based orientation. Drawing on an action research project on health care supervision, the paper questions whether we should reject earlier views...

  9. Waveguide evanescent field fluorescence microscopy & its application in cell biology

    Science.gov (United States)

    Hassanzadeh, Abdollah

    There are many powerful microscopy technologies available for the investigation of bulk materials as well as for thin film samples. Nevertheless, for imaging an interface, especially live cells on a substrate and ultra thin-films, only Total Internal Reflection Fluorescence (TIRF) microscopy is available. This TIRF microscopy allows imaging without interference of the bulk. Various approaches are employed in fluorescence microscopy applications to restrict the excitation and detection of fluorophores to a thin region of the specimen. Elimination of background fluorescence from outside the focal plane can dramatically improve the signal-to-noise ratio, and consequently, the spatial resolution of the features or events of interest. TIRF microscopy is an evanescent field based microscopy. In this method, fluorescent dyes are only excited within an evanescent field: roughly within 100 nm above a glass coverslip. This will allow imaging surface and interfacial issues of the glass coverslip and an adjacent material. Waveguide evanescent field fluorescence (WEFF) microscopy is a new development for imaging cell-substrate interactions in real time and in vitro. It is an alternative to TIRF microscopy. In this method the light is coupled into a waveguide via an optical grating. The coupled light propagates as a waveguide mode and exhibits an evanescent field on top of the waveguide. This can be used as a surface-bound illumination source to excite fluorophores. This evanescent field serves as an extremely powerful tool for quality control of thin films, to study cell-substrate contacts, and investigating the effect of external agents and drugs on the cell-substrate interaction in real time and in vitro. This new method has been established and optimized to minimize non-uniformity, scattering and photo bleaching issues. Visualizing and quantifying of the cell-substrates and solid thin films have been carried out by WEFF microscopy. The images of the cell-substrate interface

  10. Enhanced sensitivity to dielectric function and thickness of absorbing thin films by combining total internal reflection ellipsometry with standard ellipsometry and reflectometry

    International Nuclear Information System (INIS)

    Lizana, A; Foldyna, M; Garcia-Caurel, E; Stchakovsky, M; Georges, B; Nicolas, D

    2013-01-01

    High sensitivity of spectroscopic ellipsometry and reflectometry for the characterization of thin films can strongly decrease when layers, typically metals, absorb a significant fraction of the light. In this paper, we propose a solution to overcome this drawback using total internal reflection ellipsometry (TIRE) and exciting a surface longitudinal wave: a plasmon-polariton. As in the attenuated total reflectance technique, TIRE exploits a minimum in the intensity of reflected transversal magnetic (TM) polarized light and enhances the sensitivity of standard methods to thicknesses of absorbing films. Samples under study were stacks of three films, ZnO : Al/Ag/ZnO : Al, deposited on glass substrates. The thickness of the silver layer varied from sample to sample. We performed measurements with a UV–visible phase-modulated ellipsometer, an IR Mueller ellipsometer and a UV–NIR reflectometer. We used the variance–covariance formalism to evaluate the sensitivity of the ellipsometric data to different parameters of the optical model. Results have shown that using TIRE doubled the sensitivity to the silver layer thickness when compared with the standard ellipsometry. Moreover, the thickness of the ZnO : Al layer below the silver layer can be reliably quantified, unlike for the fit of the standard ellipsometry data, which is limited by the absorption of the silver layer. (paper)

  11. Social assistance and disability in Brazil: the reflection of the international debate of the rights of people with disability

    Directory of Open Access Journals (Sweden)

    Wederson Rufino dos Santos

    2010-07-01

    Full Text Available This paper reviews the debate on the social model of disability has influenced conceptions of the International Classification of Functioning, Disability and Health adopted by the World Health Organization in 2001 and adopted in Brazil in 2007, through the law of the Continuous Cash Benefit. The BPC is a major social policy of income transfer to poor disabled people, affecting over one million and half disabled people in the country. Since 2009, the evaluation of persons with disabilities for the BPC will make by medical and social skills targeted by ICF. Will be demonstrated that, although the adoption of the ICF maybe to represent regard to how to understand disability as social inequality, the adoption of the ICF by the law of the BPC will face challenges in ensuring the right to dignity of disabled people.

  12. Growth curves and the international standard: How children's growth reflects challenging conditions in rural Timor-Leste.

    Science.gov (United States)

    Spencer, Phoebe R; Sanders, Katherine A; Judge, Debra S

    2018-02-01

    Population-specific growth references are important in understanding local growth variation, especially in developing countries where child growth is poor and the need for effective health interventions is high. In this article, we use mixed longitudinal data to calculate the first growth curves for rural East Timorese children to identify where, during development, deviation from the international standards occurs. Over an eight-year period, 1,245 children from two ecologically distinct rural areas of Timor-Leste were measured a total of 4,904 times. We compared growth to the World Health Organization (WHO) standards using z-scores, and modeled height and weight velocity using the SuperImposition by Translation And Rotation (SITAR) method. Using the Generalized Additive Model for Location, Scale and Shape (GAMLSS) method, we created the first growth curves for rural Timorese children for height, weight and body mass index (BMI). Relative to the WHO standards, children show early-life growth faltering, and stunting throughout childhood and adolescence. The median height and weight for this population tracks below the WHO fifth centile. Males have poorer growth than females in both z-BMI (p = .001) and z-height-for-age (p = .018) and, unlike females, continue to grow into adulthood. This is the most comprehensive investigation to date of rural Timorese children's growth, and the growth curves created may potentially be used to identify future secular trends in growth as the country develops. We show significant deviation from the international standard that becomes most pronounced at adolescence, similar to the growth of other Asian populations. Males and females show different growth responses to challenging conditions in this population. © 2017 Wiley Periodicals, Inc.

  13. Internal Marketing and Reflective Subjects Formation Marketing Interno e a Formação de Sujeitos Reflexivos

    Directory of Open Access Journals (Sweden)

    Sérgio Carvalho Benício de Mello

    2011-03-01

    Full Text Available Internal marketing perspective has gaining primordial space. It happens through an interdisciplinary process with human management discipline and is based on the assumption that a significant part of the organizational success depends on the attitudes, commitment and performance of people in an organization, above all the ones that interact with the customers. Assuming the premise that such procedure depends on the relationship between the contact employees and the customers of an organization, we revise in this essay fundamental notions of interpresonel relationships to discuss the role of the internal marketing in the formation of employees that becomes reflexive subjects. We understand such premise as a fundamental characteristic for those to carry out his/her role in a conscious way. Our conclusion is a theoretical proposal of how this can be developed.A perspectiva do marketing interno tem ganho espaço primordial. Isto ocorre por meio de um processo interdisciplinar com a gestão de pessoas, por se compreender que parte do êxito organizacional dependa das atitudes, do comprometimento e do desempenho de todos os envolvidos numa organização, sobretudo os que interagem com os clientes. Assumindo a premissa de que tal procedimento dependa do relacionamento entre o funcionário de contato e os clientes de uma organização, neste ensaio teórico revisamos noções fundamentais do conhecimento acerca das relações interpessoais para discutir o papel do marketing interno na formação de funcionários que se tornem sujeitos reflexivos. Tal premissa é por nos compreendida como característica fundamental para que estes desempenhem seu papel de forma consciente. Nossa chegada é uma proposta teórica de como isto possa ser desenvolvido.

  14. Effects of a strong magnetic field on internal gravity waves: trapping, phase mixing, reflection and dynamical chaos

    Science.gov (United States)

    Loi, Shyeh Tjing; Papaloizou, John C. B.

    2018-04-01

    The spectrum of oscillation modes of a star provides information not only about its material properties (e.g. mean density), but also its symmetries. Spherical symmetry can be broken by rotation and/or magnetic fields. It has been postulated that strong magnetic fields in the cores of some red giants are responsible for their anomalously weak dipole mode amplitudes (the "dipole dichotomy" problem), but a detailed understanding of how gravity waves interact with strong fields is thus far lacking. In this work, we attack the problem through a variety of analytical and numerical techniques, applied to a localised region centred on a null line of a confined axisymmetric magnetic field which is approximated as being cylindrically symmetric. We uncover a rich variety of phenomena that manifest when the field strength exceeds a critical value, beyond which the symmetry is drastically broken by the Lorentz force. When this threshold is reached, the spatial structure of the g-modes becomes heavily altered. The dynamics of wave packet propagation transitions from regular to chaotic, which is expected to fundamentally change the organisation of the mode spectrum. In addition, depending on their frequency and the orientation of field lines with respect to the stratification, waves impinging on different parts of the magnetised region are found to undergo either reflection or trapping. Trapping regions provide an avenue for energy loss through Alfvén wave phase mixing. Our results may find application in various astrophysical contexts, including the dipole dichotomy problem, the solar interior, and compact star oscillations.

  15. Reflections on nuclear challenges today. 6 December 2005, London, UK, International Institute for Strategic Studies, Allistair Buchan Lecture

    International Nuclear Information System (INIS)

    ElBaradei, M.

    2005-01-01

    Emerging nuclear challenges are proliferation of nuclear weapons and sensitive nuclear technologies, emergence of nuclear clandestine procurement networks in nuclear materials and equipment and the sluggishment in nuclear disarmament. Practical steps to address them are 1) better control of access to nuclear fuel cycle technology; 2) supporting effective nuclear verification; 3) strengthening the credibility of enforcement mechanisms; 4) protecting nuclear material and 5) developing an alternative approach to collective security. For better control of access to nuclear fuel cycle technology a group of international experts proposes to a) provide assurance of supply of reactor technology and nuclear fuel; b) accept a time-limited moratorium (of perhaps 5-10 years) on new uranium enrichment and plutonium separation facilities - at the very least for countries that do not currently have such technologies; c) establish a framework for multilateral management and control of the 'back end' of the fuel cycle (i.e. spent fuel reprocessing and waste disposal); and d) create a similar framework for multilateral management and control of the 'front end' of the fuel cycle (i.e. enrichment and fuel production). The effectiveness of nuclear verification depends on the extend of access to information and locations in a given country and inspections can only verify what countries declare. The expanded access provided by the Additional Protocol to safeguards agreements enables the Agency to verify possible undeclared activities however both safeguards agreements are focused on nuclear material and therefore the Agency's authority to investigate possible parallel weaponization activity is limited. In addition only 70 countries have the additional protocol on force. A dditional transparency measures' may be required as well as additional funding to support R and D on new technologies for detecting clandestine nuclear facilities and activity. An important step to address the nuclear

  16. "Contagion" between the emerging and developed capital markets: empirical evidence and reflections on the international portfolio diversification

    Directory of Open Access Journals (Sweden)

    Wagner Moura Lamounier

    2008-10-01

    Full Text Available In this research, we analyzed the short and long term interdependence and relationship between the stock indices of the major emerging capital markets and the major developed markets for the period 1995-2005. The aim was to verify the existence and the dynamics of the “contagion” between the markets, or if the occurrence of crises and changes in the behavior of a market would have impacts on the behavior of the others. In the development of the work, we applied the methodology of the Vector Error Correction Model (VEC. We found the presence of cointegrating relationships between the markets analyzed, but was able to see that, despite being cointegrated markets, investors could benefit from international diversification of portfolios. That’s because the speed of adjustment of the long-term ratio of cointegration between the markets was low for the period analyzed. Accordingly, investors would have the opportunity to reduce risk by diversifying their portfolios.

  17. An Action Research into International Masters Program in Practicing Management (IMPM: Suggesting Refraction to Complement Reflection for Management Learning in the Global Knowledge Economy

    Directory of Open Access Journals (Sweden)

    Tunc D. MEDENI

    2008-05-01

    Full Text Available International Masters Program in Practicing Management (IMPM is a collaborative effort by major business schools and corporations around the world, balancing practical and academic issues within pedagogy of “experienced reflection”. This action research into the IMPM aims to explain the IMPM and its importance for the global knowledge economy, as well as identify and improve the current limitations of the program. As a result, we hope to provide specific suggestions for the IMPM practice and general guidelines for business education. Our suggestions are based upon a framework of “refraction” that follows a methodology of action research and pluralistic knowledge science epistemology, a critique of management learning, and a literature review on (critical reflection, as well as our findings about the IMPM practice. Also, critically reviewing Mintzberg and other authors’ ideas on management learning and IMPM specifically supports our discussion in this paper.

  18. Total internal reflection quasiphase matching-based broadband second harmonic generation in a plane-parallel uniaxial crystal of lithium niobate

    Science.gov (United States)

    Barma, Minakshi Deb; Deb, Sumita; Saha, Ardhendu

    2018-01-01

    The present work analytically investigates the generation of broadband second harmonic (SH) using total internal reflection (TIR) quasiphase matching technique in a plane-parallel uniaxial crystal having optic axis nonparallel with respect to the horizontal base. A computer-aided simulation has been performed using lithium niobate as the nonlinear material to determine the possibility of generating broadband SH intensity when broadband fundamental laser radiation is allowed to undergo TIR inside the crystal. The simulated results indicate a peak conversion efficiency of 5.22% with a spectral bandwidth (BW) of 116 nm, centered at 2.258 μm in a 10-mm-long slab. The effect of variation in operating temperature, crystal length, crystal thickness, angle of deviation of optic axis, and angle of incidence of fundamental beam at the air-prism interface on efficiency and BW of resulting SH output has been studied.

  19. Magnetic force microscopy : Quantitative issues in biomaterials

    NARCIS (Netherlands)

    Passeri, D.; Dong, C.; Reggente, M.; Angeloni, L.; Barteri, M.; Scaramuzzo, F.A.; De Angelis, F.; Marinelli, F.; Antonelli, F.; Rinaldi, F.; Marianecci, C.; Carafa, M.; Sorbo, A.; Sordi, D.; Arends, I.W.C.E.; Rossi, M.

    2014-01-01

    Magnetic force microscopy (MFM) is an atomic force microscopy (AFM) based technique in which an AFM tip with a magnetic coating is used to probe local magnetic fields with the typical AFM spatial resolution, thus allowing one to acquire images reflecting the local magnetic properties of the samples

  20. A simple method for migrating narrow aperture, noisy seismic reflection data and application to Project INDEPTH (International Deep Profiling of Tibet and the Himalaya) deep seismic profiles

    Science.gov (United States)

    Alsdorf, Doug

    1997-08-01

    Migration of deep seismic data is often hindered by a narrow recording aperture (line length by record length) and a low signal-to-noise ratio. The severity of typical migration artifacts (e.g., lateral smearing of discontinuous reflections into synforms, "smiles") increases with travel time such that interpreters of deep seismic data have often substituted migrated line drawings for the actual sections. As part of Project INDEPTH (International Deep Profiling of Tibet and the Himalaya), a new migration method was developed to address both the noise and migration issues. The method works in the time-space domain and uses the simple, constant velocity, straight ray path to perform the migration. First, only amplitudes within a given range are retained for migration, thus avoiding high-amplitude noise bursts and low-amplitude background noise. Then, the local dip of a reflection is found by automatically fitting a straight line to the highest amplitudes within a small window (several time samples by several traces) and calculating the dip of the line using a constant velocity. Finally, using this dip, the method migrates a selected amplitude value. The dips, lateral positions, and depths of the migrated events compare very well with output from more conventional algorithms (e.g.,fk-Stolt, finite difference, etc.). The advantages of the new method include fewer artifacts, fast computer run times, low memory use and the ability to migrate long profiles and travel times (e.g., 50 s). The output of the method is a grid of migrated amplitudes (not wavelets) or dip values which is particularly effective for making small figures, such as those needed for publication. The principal disadvantage is the use of a constant migration velocity.

  1. The development of optical microscopy techniques for the advancement of single-particle studies

    Energy Technology Data Exchange (ETDEWEB)

    Marchuk, Kyle [Iowa State Univ., Ames, IA (United States)

    2013-05-15

    Single particle orientation and rotational tracking (SPORT) has recently become a powerful optical microscopy tool that can expose many molecular motions. Unfortunately, there is not yet a single microscopy technique that can decipher all particle motions in all environmental conditions, thus there are limitations to current technologies. Within, the two powerful microscopy tools of total internal reflection and interferometry are advanced to determine the position, orientation, and optical properties of metallic nanoparticles in a variety of environments. Total internal reflection is an optical phenomenon that has been applied to microscopy to produce either fluorescent or scattered light. The non-invasive far-field imaging technique is coupled with a near-field illumination scheme that allows for better axial resolution than confocal microscopy and epi-fluorescence microscopy. By controlling the incident illumination angle using total internal reflection fluorescence (TIRF) microscopy, a new type of imaging probe called “non-blinking” quantum dots (NBQDs) were super-localized in the axial direction to sub-10-nm precision. These particles were also used to study the rotational motion of microtubules being propelled by the motor protein kinesin across the substrate surface. The same instrument was modified to function under total internal reflection scattering (TIRS) microscopy to study metallic anisotropic nanoparticles and their dynamic interactions with synthetic lipid bilayers. Utilizing two illumination lasers with opposite polarization directions at wavelengths corresponding to the short and long axis surface plasmon resonance (SPR) of the nanoparticles, both the in-plane and out-of-plane movements of many particles could be tracked simultaneously. When combined with Gaussian point spread function (PSF) fitting for particle super-localization, the binding status and rotational movement could be resolved without degeneracy. TIRS microscopy was also used to

  2. Selected techniques in radioecology: Model development and comparison for internal dosimetry of rainbow trout (Oncorhynchus mykiss) and feasibiltiy assessment of reflectance spectroscopy use as a tool in phytoremediation

    Science.gov (United States)

    Martinez, Nicole

    The first study in Part 1 examines the effects of lake tropic structure on the uptake of iodine-131 (131I) in rainbow trout (Oncorhynchus mykiss) and considers a simple computational model for the estimation of resulting radiation dose. Iodine-131 is a major component of the atmospheric releases following reactor accidents, and the passage of 131I through food chains from grass to human thyroids has been extensively studied. By comparison, the fate and effects of 131I deposition onto lakes and other aquatic systems has been less studied. In this study we reanalyze 1960s data from experimental releases of 131I into two small lakes and compare the effects of differences in lake trophic structures on 131I accumulation in fish. The largest concentrations in the thyroids of trout may occur from 8 to 32 days post initial release. DCFs for trout for whole body as well as thyroid were computed using Monte Carlo modeling with an anatomically-appropriate model of trout thyroid structure. Activity concentration data was used in conjunction with the calculated DCFs to estimate dose rates and ultimately determine cumulative radiation dose (Gy) to the thyroids after 32 days. The estimated cumulative thyroid doses at 32 days post-release ranged from 6 mGy to 18 mGy per 1 Bq mL-1 of initial 131I in the water, depending upon fish size. The subsequent studies in Part 1 seek to develop and compare different, increasingly detailed anatomical phantoms for O. mykiss for the purpose of estimating organ radiation dose and dose rates from 131I uptake and from molybdenum-99 (99Mo) uptake. Model comparison and refinement is important to the process of determining both dose rates and dose effects, and we develop and compare three models for O. mykiss: a simplistic geometry considering a single organ, a more specific geometry employing anatomically relevant organ size and location, and voxel reconstruction of internal anatomy obtained from CT imaging (referred to as CSUTROUT). Dose Conversion

  3. Direct quantitative screening of influenza A virus without DNA amplification by single-particle dual-mode total internal reflection scattering.

    Science.gov (United States)

    Lee, Seungah; Chakkarapani, Suresh Kumar; Yeung, Edward S; Kang, Seong Ho

    2017-01-15

    Quantitative screening of influenza A (H7N9) virus without DNA amplification was performed based on single-particle dual-mode total internal reflection scattering (SD-TIRS) with a transmission grating (TG). A gold nanopad was utilized as a substrate for the hybridization of probe DNA molecules with the TIRS nanotag (silver-nanoparticle). The TG effectively isolated the scattering signals in first-order spectral images (n=+1) of the nanotag from that of the substrate, providing excellent enhancement of signal-to-noise and selectivity. By using single-DNA molecule/TIRS nanotag hybridization, target DNA molecules of H7N9 were detected down to 74 zM, which is at least 100,000 times lower than the current detection limit of 9.4fM. By simply modifying the design of the probe DNA molecules, this technique can be used to directly screen other viral DNAs in various human biological samples at the single-molecule level without target amplification. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Evidence for highly localized damage in internal tin and powder-in-tube Nb{sub 3}Sn strands rolled before reaction obtained from coupled magneto-optical imaging and confocal laser scanning microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Polyanskii, A A; Lee, P J; Jewell, M C; Larbalestier, D C [Applied Superconductivity Center, National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310 (United States); Barzi, E; Turrioni, D; Zlobin, A V [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States)

    2009-09-15

    Nb{sub 3}Sn strands for high-current, high-field magnets must be cabled before reaction while the conductor is still composed of ductile components. Even though still in the ductile, deformable state, significant damage can occur in this step, which expresses itself by inhomogeneous A15 formation, Sn leakage or even worse effects during later reaction. In this study, we simulate cabling damage by rolling recent high performance powder-in-tube (PIT) and internal tin (IT) strands in controlled increments, applying standard Nb{sub 3}Sn reaction heat treatments, and then examining the local changes using magneto-optical imaging (MOI), scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). These combined characterizations allow any local damage to the filament architecture to be made clear. MOI directly reveals the local variation of superconductivity while CLSM is extremely sensitive in revealing Sn leakage beyond the diffusion barrier into the stabilizing Cu. These techniques reveal a markedly different response to deformation by the PIT and IT strands. The study demonstrates that these tools can provide a local, thorough, and detailed view of how strands degrade and thus complement more complex extracted strand studies.

  5. The Reflective Learning Continuum: Reflecting on Reflection

    Science.gov (United States)

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

    2005-01-01

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

  6. Correlated Light Microscopy and Electron Microscopy

    NARCIS (Netherlands)

    Sjollema, Klaas A.; Schnell, Ulrike; Kuipers, Jeroen; Kalicharan, Ruby; Giepmans, Ben N. G.; MullerReichert, T; Verkade, P

    2012-01-01

    Understanding where, when, and how biomolecules (inter)act is crucial to uncover fundamental mechanisms in cell biology. Recent developments in fluorescence light microscopy (FLM) allow protein imaging in living cells and at the near molecular level. However, fluorescence microscopy only reveals

  7. International

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    This rubric reports on 10 short notes about international economical facts about nuclear power: Electricite de France (EdF) and its assistance and management contracts with Eastern Europe countries (Poland, Hungary, Bulgaria); Transnuclear Inc. company (a 100% Cogema daughter company) acquired the US Vectra Technologies company; the construction of the Khumo nuclear power plant in Northern Korea plays in favour of the reconciliation between Northern and Southern Korea; the delivery of two VVER 1000 Russian reactors to China; the enforcement of the cooperation agreement between Euratom and Argentina; Japan requested for the financing of a Russian fast breeder reactor; Russia has planned to sell a floating barge-type nuclear power plant to Indonesia; the control of the Swedish reactor vessels of Sydkraft AB company committed to Tractebel (Belgium); the renewal of the nuclear cooperation agreement between Swiss and USA; the call for bids from the Turkish TEAS electric power company for the building of the Akkuyu nuclear power plant answered by three candidates: Atomic Energy of Canada Limited (AECL), Westinghouse (US) and the French-German NPI company. (J.S.)

  8. What we do and do not know about women and kidney diseases; Questions unanswered and answers unquestioned: Reflection on World Kidney Day and International Woman’s Day

    Directory of Open Access Journals (Sweden)

    Giorgina B Piccoli

    2018-03-01

    Full Text Available Chronic Kidney Disease affects approximately 10% of the world’s adult population: it is within the top 20 causes of death worldwide, and its impact on patients and their families can be devastating. World Kidney Day and International Women’s Day in 2018 coincide, thus offering an opportunity to reflect on the importance of women’s health and specifically their kidney health, on the community, and the next generations, as well as to strive to be more curious about the unique aspects of kidney disease in women so that we may apply those learnings more broadly. Girls and women, who make up approximately 50% of the world’s population, are important contributors to society and their families. Gender differences continue to exist around the world in access to education, medical care, and participation in clinical studies. Pregnancy is a unique state for women, offering an opportunity for diagnosis of kidney disease, but also a state where acute and chronic kidney diseases may manifest, and which may impact future generations with respect to kidney health. There are various autoimmune and other conditions that are more likely to impact women with profound consequences for child bearing, and on the fetus. Women have different complications on dialysis than men, and are more likely to be donors than recipients of kidney transplants. In this editorial, we focus on what we do and do not know about women, kidney health, and kidney disease, and what we might learn in the future to improve outcomes worldwide

  9. What we do and do not know about women and kidney diseases; questions unanswered and answers unquestioned: Reflection on World Kidney Day and International Woman's Day

    Directory of Open Access Journals (Sweden)

    Giorgina B. Piccoli

    2018-03-01

    Full Text Available Chronic kidney disease affects approximately 10% of the world's adult population: it is within the top 20 causes of death worldwide, and its impact on patients and their families can be devastating. World Kidney Day and International Women's Day in 2018 coincide, thus offering an opportunity to reflect on the importance of women's health and specifically their kidney health, on the community, and the next generations, as well as to strive to be more curious about the unique aspects of kidney disease in women so that we may apply those learnings more broadly.Girls and women, who make up approximately 50% of the world's population, are important contributors to society and their families. Gender differences continue to exist around the world in access to education, medical care, and participation in clinical studies. Pregnancy is a unique state for women, offering an opportunity for diagnosis of kidney disease, but also a state where acute and chronic kidney diseases may manifest, and which may impact future generations with respect to kidney health. There are various autoimmune and other conditions that are more likely to impact women with profound consequences for child bearing, and on the fetus. Women have different complications on dialysis than men, and are more likely to be donors than recipients of kidney transplants.In this editorial, we focus on what we do and do not know about women, kidney health, and kidney disease, and what we might learn in the future to improve outcomes worldwide. Keywords: Women, Access to care, Kidney health, Acute and chronic kidney disease, Inequities

  10. A Q-Methodology approach to investigating the relationship between level of reflection and typologies among prospective teachers in the physics learning assistant program at Florida International University

    Science.gov (United States)

    Cochran, Geraldine L.

    The purpose of this mixed methods study was to understand physics Learning Assistants' (LAs) views on reflective teaching, expertise in teaching, and LA program teaching experience and to determine if views predicted level of reflection evident in writing. Interviews were conducted in Phase One, Q methodology was used in Phase Two, and level of reflection in participants' writing was assessed using a rubric based on Hatton and Smith's (1995) "Criteria for the Recognition of Evidence for Different Types of Reflective Writing" in Phase Three. Interview analysis revealed varying perspectives on content knowledge, pedagogical knowledge, and experience in relation to expertise in teaching. Participants revealed that they engaged in reflection on their teaching, believed reflection helps teachers improve, and found peer reflection beneficial. Participants believed teaching experience in the LA program provided preparation for teaching, but that more preparation was needed to teach. Three typologies emerged in Phase Two. Type One LAs found participation in the LA program rewarding and believed expertise in teaching does not require expertise in content or pedagogy, but it develops over time from reflection. Type Two LAs valued reflection, but not writing reflections, felt the LA program teaching experience helped them decide on non-teaching careers and helped them confront gaps in their physics knowledge. Type Three LAs valued reflection, believed expertise in content and pedagogy are necessary for expert teaching, and felt LA program teaching experience increased their likelihood of becoming teachers, but did not prepare them for teaching. Writing assignments submitted in Phase Three were categorized as 19% descriptive writing, 60% descriptive reflections, and 21% dialogic reflections. No assignments were categorized as critical reflection. Using ordinal logistic regression, typologies that emerged in Phase Two were not found to be predictors for the level of reflection

  11. Microsphere imaging with confocal microscopy and two photon microscopy

    International Nuclear Information System (INIS)

    Chun, Hyung Su; An, Kyung Won; Lee, Jai Hyung

    2002-01-01

    We have acquired images of polystyrene and fused-silica microsphere by using conventional optical microscopy, confocal microscopy and two-photon microscopy, and performed comparative analysis of these images. Different from conventional optical microscopy, confocal and two-photon microscopy had good optical sectioning capability. In addition, confocal microscopy and two-photon microscopy had better lateral resolution than conventional optical microscopy. These results are attributed to confocality and nonlinearity of confocal microscopy and two photon microscopy, respectively.

  12. Reflective photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Lentine, Anthony L.; Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Goeke, Ronald S.

    2018-03-06

    A photovoltaic module includes colorized reflective photovoltaic cells that act as pixels. The colorized reflective photovoltaic cells are arranged so that reflections from the photovoltaic cells or pixels visually combine into an image on the photovoltaic module. The colorized photovoltaic cell or pixel is composed of a set of 100 to 256 base color sub-pixel reflective segments or sub-pixels. The color of each pixel is determined by the combination of base color sub-pixels forming the pixel. As a result, each pixel can have a wide variety of colors using a set of base colors, which are created, from sub-pixel reflective segments having standard film thicknesses.

  13. Electron microscopy for Engineers

    International Nuclear Information System (INIS)

    Jones, I P

    2009-01-01

    This paper reviews the application of (mainly) Transmission Electron Microscopy (TEM) in an engineering context. The first two sections are TEM and chemical in nature; the final three sections are more general and include aspects of Scanning Electron Microscopy (SEM).

  14. Guests and Hosts--The Global Market in International Higher Education: Reflections on the Japan-UK Axis in Study Abroad

    Science.gov (United States)

    Walker, Patricia

    2010-01-01

    Taking as a starting point the present ubiquity of international student mobility, contrasting paradigms of international study are offered through a critical examination of two nations. The UK is presented as a leading host nation and provider of international higher education, significant revenue from which is central to the prosperity of the…

  15. “Intellectual developmental disorders”: reflections on the international consensus document for redefining “mental retardation-intellectual disability” in ICD-11

    Science.gov (United States)

    Bertelli, Marco O.; Munir, Kerim; Harris, James; Salvador-Carulla, Luis

    2016-01-01

    Purpose The debate as to whether intellectual disability (ID) should be conceptualized as a health condition or as a disability has intensified as the revision of World Health Organization’s (WHO’s) International Classification of Diseases (ICD) is being finalized. Defining ID as a health condition is central to retaining it in ICD, with significant implications for health policy and access to health services. The purpose of this paper is to include some reflections on the consensus document produced by the first WHO Working Group on the Classification of MR (WHO WG-MR) and on the process that was followed to realize it. The consensus report was the basis for the development of official recommendations sent to the WHO Advisory Group for ICD-11. Design/methodology/approach A mixed qualitative approach was followed in a series of meetings leading to the final consensus report submitted to the WHO Advisory group. These recommendations combined prior expert knowledge with available evidence; a nominal approach was followed throughout with face-to-face conferences. Findings The WG recommended a synonym set (“synset”) ontological approach to the conceptualisation of this health condition underlying a clinical rationale for its diagnosis. It proposed replacing MR with Intellectual Developmental Disorders (IDD) in ICD-11, defined as “a group of developmental conditions characterized by a significant impairment of cognitive functions, which are associated with limitations of learning, adaptive behaviour and skills”. The WG further advised that IDD be included under the parent category of neurodevelopmental disorders, that current distinctions (mild, moderate, severe and profound) be continued as severity qualifiers, and that problem behaviours removed from its core classification structure and instead described as associated features. Originality/value Within the ID/IDD synset two different names combine distinct aspects under a single construct that describes

  16. Reflection: A Socratic approach.

    Science.gov (United States)

    Van Seggelen-Damen, Inge C M; Van Hezewijk, René; Helsdingen, Anne S; Wopereis, Iwan G J H

    2017-12-01

    Reflection is a fuzzy concept. In this article we reveal the paradoxes involved in studying the nature of reflection. Whereas some scholars emphasize its discursive nature, we go further and underline its resemblance to the self-biased dialogue Socrates had with the slave in Plato's Meno . The individual and internal nature of the reflection process creates difficulty for studying it validly and reliably. We focus on methodological issues and use Hans Linschoten's view of coupled systems to identify, analyze, and interpret empirical research on reflection. We argue that researchers and research participants can take on roles in several possible system couplings. Depending on who controls the manipulation of the stimulus, who controls the measuring instrument, who interprets the measurement and the response, different types of research questions can be answered. We conclude that reflection may be validly studied by combining different couplings of experimenter, manipulation, stimulus, participant, measurement, and response.

  17. Three-band, 1.9-μm axial resolution full-field optical coherence microscopy over a 530-1700 nm wavelength range using a single camera

    OpenAIRE

    Federici, Antoine; Dubois, Arnaud

    2014-01-01

    International audience; Full-field optical coherence microscopy is an established optical technology based on low-coherence interference microscopy for high-resolution imaging of semitransparent samples. In this Letter, we demonstrate an extension of the technique using a visible to short-wavelength infrared camera and a halogen lamp to image in three distinct bands centered at 635, 870, and 1170 nm. Reflective microscope objectives are employed to minimize chromatic aberrations of the imagin...

  18. Personal Reflections

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Personal Reflections. Articles in Resonance – Journal of Science Education. Volume 6 Issue 3 March 2001 pp 90-93 Personal Reflections. Why did I opt for Career in Science? Jayant V Narlikar · More Details Fulltext PDF. Volume 9 Issue 8 August 2004 pp 89-89 ...

  19. Reflection groups

    International Nuclear Information System (INIS)

    Eggermont, G.

    2006-01-01

    In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

  20. Quantifying Reflection

    DEFF Research Database (Denmark)

    Alcock, Gordon Lindsay

    2013-01-01

    This paper documents 1st semester student reflections on “learning to learn” in a team-based PBL environment with quantitative and qualitative student reflective feedback on the learning gains of 60 Architectural Technology and Construction Management students at VIA University College, Denmark....... It contrasts the students’ self-assessment in a range of ‘product’ skills such as Revit, Structural Design, Mathematics of construction, Technical Installations; as well as ‘process’ competencies such as ‘Working in a team’, Sharing knowledge, Maintaining a portfolio and Reflecting ON learning and FOR learning......´ These are all based on Blooms taxonomy and levels of competence and form a major part of individual student and group learning portfolios. Key Words :Project-Based learning, Reflective Portfolios, Self assessment, Defining learning gains, Developing learning strategies , Reflections on and for learning...

  1. New microscopy for nanoimaging

    CERN Document Server

    Kinjo, Y; Watanabe, M

    2002-01-01

    Two types of new microscopy, namely, X-ray contact microscopy (XRCM) in combination with atomic force microscopy (AFM) and X-ray projection microscopy (XRPM) using synchrotron radiation and zone plate optics were used to image the fine structures of human chromosomes. In the XRCM plus AFM system, location of X-ray images on a photoresist has become far easier than that with our previous method using transmission electron microscopy coupled with the replica method. In addition, the images obtained suggested that the conformation of chromatin fiber differs from the current textbook model regarding the architecture of a eukaryotic chromosome. X-ray images with high contrast of the specimens could be obtained with XRPM. The resolution of each microscopy was about 30 and 200-300 nm for XRCM plus AFM and XRPM, respectively. (author)

  2. Reflection ciphers

    DEFF Research Database (Denmark)

    Boura, Christina; Canteaut, Anne; Knudsen, Lars Ramkilde

    2017-01-01

    study the necessary properties for this coupling permutation. Special care has to be taken of some related-key distinguishers since, in the context of reflection ciphers, they may provide attacks in the single-key setting.We then derive some criteria for constructing secure reflection ciphers...... and analyze the security properties of different families of coupling permutations. Finally, we concentrate on the case of reflection block ciphers and, as an illustration, we provide concrete examples of key schedules corresponding to several coupling permutations, which lead to new variants of the block...

  3. Microscopy and Image Analysis.

    Science.gov (United States)

    McNamara, George; Difilippantonio, Michael; Ried, Thomas; Bieber, Frederick R

    2017-07-11

    This unit provides an overview of light microscopy, including objectives, light sources, filters, film, and color photography for fluorescence microscopy and fluorescence in situ hybridization (FISH). We believe there are excellent opportunities for cytogeneticists, pathologists, and other biomedical readers, to take advantage of specimen optical clearing techniques and expansion microscopy-we briefly point to these new opportunities. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  4. CARS microscopy for imaging

    International Nuclear Information System (INIS)

    Arzumanyan Grigory; Voskanyan Karine

    2013-01-01

    Optical microscopy grows in its importance with the development of modern nanotechnology, biotechnology, methods of diagnostics and treatment of most dangerous diseases for mankind. There are several important goals of optical microscopy for biomedical studies among which the next three may be distinguished: fast imaging with high lateral spatial resolution, 3-D sectioning capability and high contrast for chemical selectivity. To meet these specific requirements, various types of both linear and nonlinear optical microscopy were elaborated. (authors)

  5. An SEM Analysis of Bearing Failure Due to Electrical Arcing (Analyse par Microscopie Electronique a Balayage de l’Endommagement d’un Roulement a Billes a la Suite de Decharges Electriques Internes).

    Science.gov (United States)

    1983-01-01

    ANALYSIS OF BEARING FAILURE DUE TO ELECTRICAL ARCING ANALYSE PAR MICROSCOPIE ELECTRONIQUE A BALAYAGE DE L’ENIDOMMAGEMENT D’UN ROULEMENT A BILLES A LA SUITE...cause of subsequent fatigue and other mechanical damage to these components. RESUME Une analyse par microscopie 6lectronique A balayage a permis de...6vidence a la surface des billes de roulements et des voies de glissement par microscopie 6lectronique i balayage . Cela sugg~re que des d~charges

  6. Microscopy with slow electrons

    International Nuclear Information System (INIS)

    Frank, L.; Muellerova, I.; Delong, A.

    1994-01-01

    Low energy microscopy is treated as the low energy limit of electron microscopy as a whole in all its basic branches, i.e., the emission, transmission and scanning microscopy. The instrumental and methodological aspects are briefly discussed. They include the interaction of electrons with a solid, the contrast formation mechanisms, the instrumentation problems, and actual progress achieved in all three types of microscopy from the point of view of lowering the energy of electrons, impacting or leaving the specimen, down to the low energy range below 5 keV and the very low energy range below 50 eV. (author) 62 refs., 27 figs., 3 tabs

  7. Coherent light microscopy

    CERN Document Server

    Ferraro, Pietro; Zalevsky, Zeev

    2011-01-01

    This book deals with the latest achievements in the field of optical coherent microscopy. While many other books exist on microscopy and imaging, this book provides a unique resource dedicated solely to this subject. Similarly, many books describe applications of holography, interferometry and speckle to metrology but do not focus on their use for microscopy. The coherent light microscopy reference provided here does not focus on the experimental mechanics of such techniques but instead is meant to provide a users manual to illustrate the strengths and capabilities of developing techniques. Th

  8. Electron Microscopy Center (EMC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Electron Microscopy Center (EMC) at Argonne National Laboratory develops and maintains unique capabilities for electron beam characterization and applies those...

  9. Bridging fluorescence microscopy and electron microscopy

    NARCIS (Netherlands)

    Giepmans, Ben N. G.

    Development of new fluorescent probes and fluorescence microscopes has led to new ways to study cell biology. With the emergence of specialized microscopy units at most universities and research centers, the use of these techniques is well within reach for a broad research community. A major

  10. Wave Reflection Model Tests

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Larsen, Brian Juul

    The investigation concerns the design of a new internal breakwater in the main port of Ibiza. The objective of the model tests was in the first hand to optimize the cross section to make the wave reflection low enough to ensure that unacceptable wave agitation will not occur in the port. Secondly...

  11. Scanning Electron Microscopy in modern dentistry research

    OpenAIRE

    Paradella, Thaís Cachuté; Unesp-FOSJC; Bottino, Marco Antonio; Unesp-FOSJC

    2012-01-01

    The purpose of this article was to review the usage of Scanning Electron Microscopy (SEM) in dentistry research nowadays, through a careful and updated literature review. By using the key-words Scanning Electron Microscopy and one of the following areas of research in dentistry (Endodontics, Periodontics and Implant), in international database (PubMed), in the year of 2012 (from January to September), a total of 112 articles were found. This data was tabled and the articles were classified ac...

  12. Reflections on the international climate change negotiations: A synthesis of a working group on carbon emission policy and regulation in Brazil

    International Nuclear Information System (INIS)

    Lucon, Oswaldo; Romeiro, Viviane; Pacca, Sergio

    2013-01-01

    This short communication presents a synthesis of a Working Group on Carbon Emission Policy and Regulation held at the University of Sao Paulo, in Brazil. The document looked at the problems with the international negotiations, the options for Brazil as it attempts to control emissions, and ways to leverage the mitigation process. Several options are currently being proposed, but these are neither clear in order to support a solid polycentric approach with adequate metrics, nor a robust international coordination and a sound scientific communication. Brazil has a central role in this process, for having successful initiatives on renewable energy and deforestation control. Its leadership can demonstrate how such policies might take shape. However, the country´s future is uncertain in terms of low carbon development. Although the country is still well positioned among BRICS to find practical solutions to the stalemate in international cooperation, several internal challenges need to be harmonized. - Highlights: • The work presents results of a recent climate change mitigation policies workshop. • It assesses Brazil's potential role in shaping future policies and negotiations. • Policies are evaluated based on domestic and international effects. • Suggests how Brazil's national effort could leverage the international processes

  13. Lasers for nonlinear microscopy.

    Science.gov (United States)

    Wise, Frank

    2013-03-01

    Various versions of nonlinear microscopy are revolutionizing the life sciences, almost all of which are made possible because of the development of ultrafast lasers. In this article, the main properties and technical features of short-pulse lasers used in nonlinear microscopy are summarized. Recent research results on fiber lasers that will impact future instruments are also discussed.

  14. Fluorescent labeling of Acanthamoeba assessed in situ from corneal sectioned microscopy.

    Science.gov (United States)

    Marcos, Susana; Requejo-Isidro, Jose; Merayo-Lloves, Jesus; Acuña, A Ulises; Hornillos, Valentin; Carrillo, Eugenia; Pérez-Merino, Pablo; Del Olmo-Aguado, Susana; Del Aguila, Carmen; Amat-Guerri, Francisco; Rivas, Luis

    2012-10-01

    Acanthamoeba keratitis is a serious pathogenic corneal disease, with challenging diagnosis. Standard diagnostic methods include corneal biopsy (involving cell culture) and in vivo reflection corneal microscopy (in which the visualization of the pathogen is challenged by the presence of multiple reflectance corneal structures). We present a new imaging method based on fluorescence sectioned microscopy for visualization of Acanthamoeba. A fluorescent marker (MT-11-BDP), composed by a fluorescent group (BODIPY) inserted in miltefosine (a therapeutic agent against Acanthamoeba), was developed. A custom-developed fluorescent structured illumination sectioned corneal microscope (excitation wavelength: 488 nm; axial/lateral resolution: 2.6 μm/0.4-0.6 μm) was used to image intact enucleated rabbit eyes, injected with a solution of stained Acanthamoeba in the stroma. Fluorescent sectioned microscopic images of intact enucleated rabbit eyes revealed stained Acanthamoeba trophozoites within the stroma, easily identified by the contrasted fluorescent emission, size and shape. Control experiments show that the fluorescent maker is not internalized by corneal cells, making the developed marker specific to the pathogen. Fluorescent sectioned microscopy shows potential for specific diagnosis of Acanthamoeba keratitis. Corneal confocal microscopy, provided with a fluorescent channel, could be largely improved in specificity and sensitivity in combination with specific fluorescent marking.

  15. Reflectance Modeling

    Science.gov (United States)

    Smith, J. A.; Cooper, K.; Randolph, M.

    1984-01-01

    A classical description of the one dimensional radiative transfer treatment of vegetation canopies was completed and the results were tested against measured prairie (blue grama) and agricultural canopies (soybean). Phase functions are calculated in terms of directly measurable biophysical characteristics of the canopy medium. While the phase functions tend to exhibit backscattering anisotropy, their exact behavior is somewhat more complex and wavelength dependent. A Monte Carlo model was developed that treats soil surfaces with large periodic variations in three dimensions. A photon-ray tracing technology is used. Currently, the rough soil surface is described by analytic functions and appropriate geometric calculations performed. A bidirectional reflectance distribution function is calculated and, hence, available for other atmospheric or canopy reflectance models as a lower boundary condition. This technique is used together with an adding model to calculate several cases where Lambertian leaves possessing anisotropic leaf angle distributions yield non-Lambertian reflectance; similar behavior is exhibited for simulated soil surfaces.

  16. Overview of optical microscopy and optical microspectroscopy

    Science.gov (United States)

    Ager, Joel W.

    1998-11-01

    Optical microscopy has historically been a major tool for semiconductor inspection. As the ULSI design rule continues to decline to 0.25 μm and below, standard optical microscopy methods will arrive at their resolution limit. In the first part of this paper an overview of currently used optical microscopy techniques will be given. The resolution limit for optical imaging will be discussed, and novel methods for increasing resolution, including deep UV microscopy and confocal laser microscopy, will be presented. The second part of the paper will discuss an emerging technology for contamination analysis in semiconductor processing, microspectroscopy. Three topics in this area will be discussed with an emphasis on applications to off-line defect identification in process development: (1) micro-Raman spectroscopy, (2) micro-fluorescence or micro-photoluminescence spectroscopy, and (3) micro-reflectivity. It will be shown that these microspectroscopy methods can provide composition information for defects down to 1 μm in size that is not accessible through the more commonly used methods such as scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS) and scanning Auger microscopy. Classes of defects where optical micro-spectroscopy methods are useful include ceramic particles, thin films of organic material, and dielectric films.

  17. Reflective optics

    CERN Document Server

    Korsch, Dietrich

    1991-01-01

    This is the first book dedicated exclusively to all-reflective imaging systems. It is a teaching tool as well as a practical design tool for anyone who specializes in optics, particularly for those interested in telescopes, infrared, and grazing-incidence systems. The first part of the book describes a unified geometric optical theory of all-reflective imaging systems (from near-normal to grazing incidence) developed from basic principles. The second part discusses correction methods and a multitude of closed-form solutions of well-corrected systems, supplemented with many conventional and unc

  18. Optical Imaging and Microscopy Techniques and Advanced Systems

    CERN Document Server

    Török, Peter

    2007-01-01

    This text on contemporary optical systems is intended for optical researchers and engineers, graduate students and optical microscopists in the biological and biomedical sciences. This second edition contains two completely new chapters. In addition most of the chapters from the first edition have been revised and updated. The book consists of three parts: The first discusses high-aperture optical systems, which form the backbone of optical microscopes. An example is a chapter new in the second edition on the emerging field of high numerical aperture diffractive lenses which seems to have particular promise in improving the correction of lenses. In this part particular attention is paid to optical data storage. The second part is on the use of non-linear optical techniques, including nonlinear optical excitation (total internal reflection fluorescence, second and third harmonic generation and two photon microscopy) and non-linear spectroscopy (CARS). The final part of the book presents miscellaneous technique...

  19. Biological applications of near-field scanning optical microscopy

    NARCIS (Netherlands)

    Moers, Marco H.P.; Moers, M.H.P.; Ruiter, A.G.T.; Jalocha, A.; Jalocha, Alain; van Hulst, N.F.

    1995-01-01

    Near-field Scanning Optical Microscopy (NSOM) is a true optical microscopic technique allowing fluorescence, absorption, reflection and polarization contrast with the additional advantage of nanometer lateral resolution, unlimited by diffraction and operation at ambient conditions. NSOM based on

  20. Confocal Microscopy for Real Time Detection of Oral Cavity Neoplasia

    National Research Council Canada - National Science Library

    Clark, Anne

    2003-01-01

    .... Reflectance confocal images were compared to histologic images from the same sample to determine which tissue features contribute to image contrast and can be potentially imaged using in vivo confocal microscopy...

  1. Journeys into Inner/Outer Space: Reflections on the Methodological Challenges of Negotiating Insider/Outsider Status in International Educational Research

    Science.gov (United States)

    Savvides, Nicola; Al-Youssef, Joanna; Colin, Mindy; Garrido, Cecilia

    2014-01-01

    This article highlights key theoretical and methodological issues and implications of being an insider/outsider when undertaking qualitative research in international educational settings. It first addresses discourses of "self" and "other," noting that identity and belonging emerge from fluid engagement between researchers and…

  2. Does the School Performance Variable Used in the International Health Behavior in School-Aged Children (HBSC) Study Reflect Students' School Grades?

    Science.gov (United States)

    Felder-Puig, Rosemarie; Griebler, Robert; Samdal, Oddrun; King, Matthew A.; Freeman, John; Duer, Wolfgang

    2012-01-01

    Background: Given the pressure that educators and policy makers are under to achieve academic standards for students, understanding the relationship of academic success to various aspects of health is important. The international Health Behavior in School-Aged Children (HBSC) questionnaire, being used in 41 countries with different school and…

  3. Reflections on delivering a cross-discipline, cross-cultural, international, masters-level collaborative course using e-Learning technologies

    NARCIS (Netherlands)

    Leung, W.S.; Coulter, D.A.; Moes, C.C.M.; Horvath, I.

    2012-01-01

    This paper presents a case study on the experience of delivering an Internet-based international collaborative semester course at intermediate postgraduate level and attempts to distill a model for exploring the success factors involved when presenting such courses. The pedagogic and practical

  4. Confocal Raman microscopy

    CERN Document Server

    Dieing, Thomas; Hollricher, Olaf

    2018-01-01

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

  5. Personal Reflections

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Jochen and Werner Heisenberg. Personal Reflections Volume 10 Issue 1 January 2005 pp 93-96. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/010/01/0093-0096. Resonance – Journal of ...

  6. PERSONAL REFLECTIONS

    Indian Academy of Sciences (India)

    IAS Admin

    Resonance journal of science education. April 2015 Volume 20 Number 4. GENERALARTICLES ... Development of. Probability Theory. K B Athreya. Classroom. Tutorial on Phyloge- netic Inference –1. Felix Bast. 360. 346. 286. PERSONAL REFLECTIONS. 368 The Road to IISc. M L Munjal (Transcribed by Maneesh Kunte).

  7. X-ray microscopy using grazing-incidence reflection optics

    International Nuclear Information System (INIS)

    Price, R.H.

    1981-01-01

    The Kirkpatrick-Baez microscopes are described along with their role as the workhorse of the x-ray imaging devices. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics

  8. After Fukushima? On the educational and learning theoretical reflection of nuclear disasters. International perspectives; Nach Fukushima? Zur erziehungs- und bildungstheoretischen Reflexion atomarer Katastrophen. Internationale Perspektiven

    Energy Technology Data Exchange (ETDEWEB)

    Wigger, Lothar; Buenger, Carsten (eds.) [Technische Univ. Dortmund (Germany). Bereich Allgemeine Erziehungswissenschaft; Platzer, Barbara [Technische Univ. Dortmund (Germany)

    2017-08-01

    The book on the educational and learning theoretical reflection of nuclear disasters as a consequence of Fukushima includes contributions on the following issues: pedagogical approach: children write on Fukushima, description of the reality as pedagogical challenge; lessons learned on the nuclear technology - perspectives and limits of pedagogical evaluation: moral education - Japanese teaching materials, educational challenges at the universities with respect to nuclear technology and technology impact assessment; education and technology - questions concerning the pedagogical responsibility: considerations on the responsibility of scientists, on the discrepancy between technology and education, disempowerment of the public by structural corruption - nuclear disaster and post-democratic tendencies in Japan.

  9. Modeling soil moisture-reflectance

    OpenAIRE

    Muller, Etienne; Decamps, Henri

    2001-01-01

    International audience; Spectral information on soil is not easily available as vegetation and farm works prevent direct observation of soil responses. However, there is an increasing need to include soil reflectance values in spectral unmixing algorithms or in classification approaches. In most cases, the impact of soil moisture on the reflectance is unknown and therefore ignored. The objective of this study was to model reflectance changes due to soil moisture in a real field situation usin...

  10. The readability of international illustration of auditor’s report: An advanced reflection on the compromise between normative principles and linguistic requirements

    OpenAIRE

    Mondher Fakhfakh

    2015-01-01

    The independent auditors periodically publish reports that summarize the audit results. These reports reinforce the financial communication and reliability of accounting information. International Standards on Auditing (ISA) determine the content of audit reports and the quality of audit results. Theoretically, the audit standardization must model intelligible and clear reports for readers. Compliance with linguistic principles contributes to the improvement of the structure of audit reports....

  11. Towards fully automated Identification of Vesicle-Membrane Fusion Events in TIRF Microscopy

    Science.gov (United States)

    Vallotton, Pascal; James, David E.; Hughes, William E.

    2007-11-01

    Total Internal Reflection Fluorescence Microscopy (TIRFM) is imposing itself as the tool of choice for studying biological activity in close proximity to the plasma membrane. For example, the exquisite selectivity of TIRFM allows monitoring the diffusion of GFP-phogrin vesicles and their recruitment to the plasma membrane in pancreatic β-cells. We present a novel computer vision system for automatically identifying the elusive fusion events of GFP-phogrin vesicles with the plasma membrane. Our method is based on robust object tracking and matched filtering. It should accelerate the quantification of TIRFM data and allow the extraction of more biological information from image data to support research in diabetes and obesity.

  12. Public Participation and the Rights of the Child: Reflection on International Law Standards in the Legal System of the Russian Federation

    Directory of Open Access Journals (Sweden)

    Mariya Riekkinen

    2016-01-01

    Full Text Available This article deals with the much debated issue of children’s public participation from the perspective of legal practices in the Russian Federation. Having emerged at the level of national jurisdictions, the practice of engaging minors in decision-making processes on issues of public significance – or the practice of public participation of children – is stipulated by the UN Committee on the Rights of the Child, based on Article 12 of the UN Convention on the Rights of the Child. Public participation of minors implies that children have clearly defined opportunities to take part in decision-making processes concerning those political and public matters affecting their interests.Albeit limited by the clause “regarding the issues concerning them,” the claims for such participation are dictated by emerging standards of international law. The author has examined the process of devising these standards in Russian public law. Moreover, an analysis of the evolution of academic views on public participation of children in Russian legal scholarship is also included in this article.Relying extensively on the method of legal analysis and the comparative analysis of the conformity of national public law standards with respect to international law, the author proposes several legal amendments to the Federal law “On the Basic Guarantees of the Rights of the Child in the Russian Federation,” which would lead to anchoring more solidly the participatory right of minors in the legal system of the Russian Federation.

  13. 'It's something that I manage but it is not who I am': reflections on internalized stigma in individuals with bipolar disorder.

    Science.gov (United States)

    Michalak, Erin; Livingston, James D; Hole, Rachelle; Suto, Melinda; Hale, Sandra; Haddock, Candace

    2011-09-01

    Bipolar disorder (BD) is a complex chronic condition associated with substantial costs, both at a personal and societal level. Growing research indicates that experiences with stigma may play a significant role in contributing to the distress, disability, and poor quality of life (QoL) often experienced in people with BD. Here, we present a sub-set of findings from a qualitative study of self-management strategies utilized by high functioning Canadian individuals with BD. Specifically, we describe a theme relating to participants' experiences and understandings of internalized stigma. Descriptive qualitative methods were used including purposeful sampling and thematic analysis. High functioning individuals with BD type I or II (N = 32) completed quantitative scales to assess symptoms, functioning and QoL, and participated in an individual interview or focus group to discuss the self-management strategies that they use to maintain or regain wellness. Thematic analysis identified several themes, including one relating to internalized stigma. Within this, four additional themes were identified: stigma expectations and experiences, sense of self/identity, judicious disclosure, and moving beyond internalised stigma. One of the more unique aspects of the study is that it involves a participant sample that is managing well with their illness, which differs from the norm in biomedical research that typically focuses on pathology, problems and dysfunction.

  14. Light Microscopy Module (LMM)-Emulator

    Science.gov (United States)

    Levine, Howard G.; Smith, Trent M.; Richards, Stephanie E.

    2016-01-01

    The Light Microscopy Module (LMM) is a microscope facility developed at Glenn Research Center (GRC) that provides researchers with powerful imaging capability onboard the International Space Station (ISS). LMM has the ability to have its hardware recongured on-orbit to accommodate a wide variety of investigations, with the capability of remotely acquiring and downloading digital images across multiple levels of magnication.

  15. Reflective Writing

    DEFF Research Database (Denmark)

    Ahrenkiel Jørgensen, Andriette

    2016-01-01

    In Breve fra min Have (Letters from my Garden), the Swedish landscape architect, Sven-Ingvar Andersson, produces dialogues about his garden to a wide circle of friends, colleagues, deceased and still living acquaintances such as Karen Blixen, Gertrude Stein, C. Th. Sørensen, Albrecht Dürer, Peter...... Høeg etetera. The dialogues work as a tool of reflection in terms of providing opportunity to examine his own beliefs, to explore the possible reasons for engaging in a particular activity. On the basis of Sven-Ingvar Andersson’s book a teaching program at the Aarhus School of Architecture provides...

  16. Inspiring Reflections

    DEFF Research Database (Denmark)

    Muchie, Mammo

    2011-01-01

    A numberof Chris Freeman's colleagues were asked to reflect on what they thought describes his life and work in a few words. Some of the colleagues replied including former SPRU students that were taught or supervised by Chris Freeman. Their views on what they thought were Chris Freeman's defining...... life is not free from fluctuations, cycles, disruptions, crises and destructions both human and ecological. Innovation research ought to position itself to address environmental, financial and economic crises. The third is innovation research for development by addressing not only poverty erdaication...

  17. The fragility of identity: about the internal experience of gender in Law N° 26.743 Reflections from Pierre Bourdieu and Judith Butler

    Directory of Open Access Journals (Sweden)

    Lucía Inés Coppa

    2014-12-01

    Full Text Available The following article intends to approach some aspects of bourdiean thoughts in order to develop an approach to the notion of gender and the way in which – within an androcentric symbolic order and a normative heterosexual matrix – function these diagrams in the way gender makes up the subjective corporal form. From those notions, we want to reflect about the emergency of sexual identities that transgress the cultural precepts around gender founded in doxic experience. Likewise, we will sketch a brief reference among inconscient dimension across psychoanalytical tradition and performative theory across Judith Butler in the feminists debates.Through this conceptual framework we will attempt to examine how may the dominant representations of femininity, androcentric and heterosexually regulated, influence the identity formation of a feminine transsexual person, founded in the morphological ideal which has sustenance in the man-woman dichotomy, leaving the questioning open about the ways that the transgressive assumption of sex of what appears like the order of things may take in a binomic gender matrix, examining the reception of this debates in te Gender Identity Law N° 26.743

  18. More terminological clarity in the interprofessional field – a call for reflection on the use of terminologies, in both practice and research, on a national and international level

    Directory of Open Access Journals (Sweden)

    Mitzkat, Anika

    2016-04-01

    Full Text Available The terminology which has been used up until now within interprofessional healthcare has been characterised by a certain definitional weakness, which, among other factors, has been caused by an uncritical adoption of language conventions and a lack of theoretical reflection. However, as terminological clarity plays a significant role in the development and profiling of a discipline, the clarification and definition of commonly-used terminology has manifested itself as a considerable objective for the interprofessional research community. One of the most important journals for research in the area of interprofessional education and care, the Journal of Interprofessional Care, has expanded its author guidelines relating to terminology, modeled after the conceptual considerations of the research group around Barr et. al and Reeves et al. A German translation of the suggested terms therein has been presented in this contribution, and discussed in light of the challenges to a possible adaptation for the German-speaking world. The objective is to assist communication in practice and research in becoming clearer, while promoting an increasing awareness to and the transparency of determined definitions and terminologies.

  19. More terminological clarity in the interprofessional field - a call for reflection on the use of terminologies, in both practice and research, on a national and international level.

    Science.gov (United States)

    Mitzkat, Anika; Berger, Sarah; Reeves, Scott; Mahler, Cornelia

    2016-01-01

    The terminology which has been used up until now within interprofessional healthcare has been characterised by a certain definitional weakness, which, among other factors, has been caused by an uncritical adoption of language conventions and a lack of theoretical reflection. However, as terminological clarity plays a significant role in the development and profiling of a discipline, the clarification and definition of commonly-used terminology has manifested itself as a considerable objective for the interprofessional research community. One of the most important journals for research in the area of interprofessional education and care, the Journal of Interprofessional Care, has expanded its author guidelines relating to terminology, modeled after the conceptual considerations of the research group around Barr et. al and Reeves et al. A German translation of the suggested terms therein has been presented in this contribution, and discussed in light of the challenges to a possible adaptation for the German-speaking world. The objective is to assist communication in practice and research in becoming clearer, while promoting an increasing awareness to and the transparency of determined definitions and terminologies.

  20. Near-field optical microscopy in transmission and reflection modes in combination with force microscopy

    NARCIS (Netherlands)

    van Hulst, N.F.; Moers, M.H.P.; Moers, M.H.P.; Bölger, B.; Bölger, B.

    1993-01-01

    Depolarized hyper Rayleigh scattering of para-nitroaniline (C2v symmetry) and nitrocalix[4]arene (C4v symmetry) in solution has been measured. Using linearly and circularly polarized fundamental radiation information about the ratios between the several hyperpolarizability tensor components,

  1. Controllable tomography phase microscopy

    Science.gov (United States)

    Xiu, Peng; Zhou, Xin; Kuang, Cuifang; Xu, Yingke; Liu, Xu

    2015-03-01

    Tomography phase microscopy (TPM) is a new microscopic method that can quantitatively yield the volumetric 3D distribution of a sample's refractive index (RI), which is significant for cell biology research. In this paper, a controllable TPM system is introduced. In this system a circulatory phase-shifting method and piezoelectric ceramic are used which enable the TPM system to record the 3D RI distribution at a more controllable speed, from 1 to 40 fps, than in the other TPM systems reported. The resolution of the RI distribution obtained by this controllable TPM is much better than that in images recorded by phase contrast microscopy and interference tomography microscopy. The realization of controllable TPM not only allows for the application of TPM to the measurement of kinds of RI sample, but also contributes to academic and technological support for the practical use of TPM.

  2. Second harmonic generation microscopy

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline; Brewer, Jonathan R.; Risbo, Jens

    2010-01-01

    Myofibers and collagen show non-linear optical properties enabling imaging using second harmonic generation (SHG) microscopy. The technique is evaluated for use as a tool for real-time studies of thermally induced changes in thin samples of unfixed and unstained pork. The forward and the backward......-temperature endotherm peak observable in the differential scanning calorimetry (DSC) thermograms. DSC analysis of epimysium, the connective tissue layer that enfold skeletal muscles, produces one large endotherm starting at 57 °C and peaking at 59.5 °C. SHG microscopy of collagen fibers reveals a variability of thermal...... indicating regions of much higher thermal stability. It is seen that the benefits of the structural and temporal information available from SHG microscopy reveals complementary information to a traditional DSC measurement and enables a more complete understanding of the thermal denaturation process....

  3. Confocal Raman Microscopy

    CERN Document Server

    Dieing, Thomas; Toporski, Jan

    2011-01-01

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

  4. Application of Confocal Laser Scanning Microscopy in Biology and Medicine

    Directory of Open Access Journals (Sweden)

    I. A. Volkov

    2014-01-01

    Full Text Available Fluorescence confocal laser scanning microscopy and reflectance confocal laser scanning microscopy are up-to-date highend study methods. Confocal microscopy is used in cell biology and medicine. By using confocal microscopy, it is possible to study bioplasts and localization of protein molecules and other compounds relative to cell or tissue structures, and to monitor dynamic cell processes. Confocal microscopes enable layer-by-layer scanning of test items to create demonstrable 3D models. As compared to usual fluorescent microscopes, confocal microscopes are characterized by a higher contrast ratio and image definition.

  5. Basics of Digital Microscopy.

    Science.gov (United States)

    Wallace, Callen T; Jessup, Morgan; Bernas, Tytus; Peña, Karina A; Calderon, Michael J; Loughran, Patricia A

    2018-01-18

    Modern digital microscopy combines the equipment of classical light microscopy with a computerized imaging system. The technique comprises image formation by optics, image registration by a camera, and saving of image data in a computer file. This chapter describes limitations that are particular to each of these processes, including optical resolution, efficiency of image registration, characteristics of image file formats, and data management. Further suggestions are given which serve, in turn, to help construct a set of guidelines aimed at optimization of digital microscopic imaging. © 2018 by John Wiley & Sons, Inc. Copyright © 2018 John Wiley & Sons, Inc.

  6. Confocal scanning microscopy

    DEFF Research Database (Denmark)

    Bariani, Paolo

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

  7. International law

    CERN Document Server

    Shaw, Malcolm N

    2017-01-01

    International Law is the definitive and authoritative text on the subject, offering Shaw's unbeatable combination of clarity of expression and academic rigour and ensuring both understanding and critical analysis in an engaging and authoritative style. Encompassing the leading principles, practice and cases, and retaining and developing the detailed references which encourage and assist the reader in further study, this new edition motivates and challenges students and professionals while remaining accessible and engaging. Fully updated to reflect recent case law and treaty developments, this edition contains an expanded treatment of the relationship between international and domestic law, the principles of international humanitarian law, and international criminal law alongside additional material on international economic law.

  8. High-energy electron diffraction and microscopy

    CERN Document Server

    Peng, L M; Whelan, M J

    2011-01-01

    This book provides a comprehensive introduction to high energy electron diffraction and elastic and inelastic scattering of high energy electrons, with particular emphasis on applications to modern electron microscopy. Starting from a survey of fundamental phenomena, the authors introduce the most important concepts underlying modern understanding of high energy electron diffraction. Dynamical diffraction in transmission (THEED) and reflection (RHEED) geometries is treated using ageneral matrix theory, where computer programs and worked examples are provided to illustrate the concepts and to f

  9. Do measures used in studies of anxiety disorders reflect activities and participation as defined in the WHO International Classification of Functioning, Disability and Health?

    Science.gov (United States)

    Brütt, Anna Levke; Schulz, Holger; Koch, Uwe; Andreas, Sylke

    2011-07-01

    Besides the measurement of symptoms, information on functioning and disability in daily routines expands the description of impairments in patients with anxiety disorders. Therefore, the measurement of activities and participation, as theoretically included in the International Classification of Functioning, Disability and Health (ICF) is of increasing importance. The objective of this study is to give an overview over the implementation of the concept 'activities and participation' in outcome measurements of patients with anxiety disorders. Based on a literature review in PubMed and PsycInfo databases and including 200 papers, this study analyses 65 outcome instruments used in randomized controlled trials in anxiety disorders according to their content related to the ICF domain of 'Activities and participation'. Instruments used in trials evaluating outcome in patients with anxiety disorder only partially address activities and participation. Over all 65 instruments, the chapters on 'Interpersonal interactions and relationships' and 'Mobility' were most frequently included in measurements. The identification of relevant ICF categories (core sets) according to activities and participation and especially interpersonal interactions and relationships as well as mobility, can be a basis for describing functioning and evaluating treatment in anxiety disorders, helping to improve outcome assessment in clinical practice.

  10. Atomic and Molecular Photodetachment Microscopy

    Science.gov (United States)

    Blondel, Christophe

    2004-05-01

    Detachment from a negative ion leads to the emission of a nearly unperturbed free electron wave. Detachment in the presence of an electric field thus gives a unique opportunity to study the propagation of a matter wave submitted to uniform acceleration from a pointlike source. As the expression of the corresponding Green function shows, spatially resolved detection of the detached electron should reveal the existence of interference fringes, which can be interpreted as the interference between the well-known pairs of parabolic trajectories of elementary ballistics. Whereas no real free-fall experiment has been able yet to materialize those fringes, photodetachment microscopy experiments carried out since 1996 have now produced electron interference patterns from five different atomic anions. The orders of magnitude of the fringe interval and the spatial resolution of electron detectors are such that these interference patterns can be observed only in relatively weak electric fields and at low energies above the detachment thresholds. The sensitivity of the pattern with respect to the ejection energy of the electron is an interferometric way for measuring the energy brought in excess by the detaching photon, and the electron affinity of the parent neutral itself. The free-electron approximation used to analyze photodetachment microscopy images can be questioned when one deals with a big atom or a molecular anion. The first molecular photodetachment microscopy experiments were carried out recently on OH^-. They still show an observable electron interference pattern, even though OH can be left in a high angular momentum state. On a quantitative basis, the electron interferograms still appear very robust with respect to either internal or external perturbations, which should make it possible to compress the error bars on electron affinities well below 1 μeV, even in the molecular case.

  11. Scanning ultrafast electron microscopy.

    Science.gov (United States)

    Yang, Ding-Shyue; Mohammed, Omar F; Zewail, Ahmed H

    2010-08-24

    Progress has been made in the development of four-dimensional ultrafast electron microscopy, which enables space-time imaging of structural dynamics in the condensed phase. In ultrafast electron microscopy, the electrons are accelerated, typically to 200 keV, and the microscope operates in the transmission mode. Here, we report the development of scanning ultrafast electron microscopy using a field-emission-source configuration. Scanning of pulses is made in the single-electron mode, for which the pulse contains at most one or a few electrons, thus achieving imaging without the space-charge effect between electrons, and still in ten(s) of seconds. For imaging, the secondary electrons from surface structures are detected, as demonstrated here for material surfaces and biological specimens. By recording backscattered electrons, diffraction patterns from single crystals were also obtained. Scanning pulsed-electron microscopy with the acquired spatiotemporal resolutions, and its efficient heat-dissipation feature, is now poised to provide in situ 4D imaging and with environmental capability.

  12. Magnetic Force Microscopy

    NARCIS (Netherlands)

    Abelmann, Leon

    Principle of MFM In magnetic force microscopy (MFM), the magnetic stray field above a very flat specimen, or sample, is detected by placing a small magnetic element, the tip, mounted on a cantilever spring very close to the surface of the sample (Figure 1). Typical dimensions are a cantilever length

  13. Photoacoustic computed microscopy

    Science.gov (United States)

    Yao, Lei; Xi, Lei; Jiang, Huabei

    2014-05-01

    Photoacoustic microscopy (PAM) is emerging as a powerful technique for imaging microvasculature at depths beyond the ~1 mm depth limit associated with confocal microscopy, two-photon microscopy and optical coherence tomography. PAM, however, is currently qualitative in nature and cannot quantitatively measure important functional parameters including oxyhemoglobin (HbO2), deoxyhemoglobin (HbR), oxygen saturation (sO2), blood flow (BF) and rate of oxygen metabolism (MRO2). Here we describe a new photoacoustic microscopic method, termed photoacoustic computed microscopy (PACM) that combines current PAM technique with a model-based inverse reconstruction algorithm. We evaluate the PACM approach using tissue-mimicking phantoms and demonstrate its in vivo imaging ability of quantifying HbO2, HbR, sO2, cerebral BF and cerebral MRO2 at the small vessel level in a rodent model. This new technique provides a unique tool for neuroscience research and for visualizing microvasculature dynamics involved in tumor angiogenesis and in inflammatory joint diseases.

  14. Direct immunofluorescence microscopy

    NARCIS (Netherlands)

    Diercks, G.F.H.; Pas, Hendrikus; Jonkman, Marcel

    2016-01-01

    Direct immunofluorescence plays an important role in the diagnosis of autoimmune bullous diseases. The purpose of direct immunofluorescence microscopy is to detect in vivo antibodies in patient's skin or mucosa. Direct immunofluorescence of pemphigus shows depositions of immunoglobulins and/or

  15. Fluorescence confocal polarizing microscopy

    Indian Academy of Sciences (India)

    Much of the modern understanding of orientational order in liquid crystals (LCs) is based on polarizing microscopy (PM). A PM image bears only two-dimensional (2D) information, integrating the 3D pattern of optical birefringence over the path of light. Recently, we proposed a technique to image 3D director patterns by ...

  16. Microscopy of femtoscale structures

    Indian Academy of Sciences (India)

    Microscopy of femtoscale structures. P CHOWDHURY. Department of Physics, University of Massachusetts Lowell, Lowell MA 01854, USA. Abstract. Advances in experimental techniques are discussed for the study of long-lived isomers using gammasphere. Spectroscopy of neutron-rich nuclei in the A. 180 region is made ...

  17. Ballistic hole magnetic microscopy

    NARCIS (Netherlands)

    Haq, E.; Banerjee, T.; Siekman, M.H.; Lodder, J.C.; Jansen, R.

    2005-01-01

    A technique to study nanoscale spin transport of holes is presented: ballistic hole magnetic microscopy. The tip of a scanning tunneling microscope is used to inject hot electrons into a ferromagnetic heterostructure, where inelastic decay creates a distribution of electron-hole pairs.

  18. Advanced Microscopy of Microbial Cells

    DEFF Research Database (Denmark)

    Haagensen, Janus Anders Juul; Regenberg, Birgitte; Sternberg, Claus

    2011-01-01

    microscopy, super-resolution optical microscopy (STED, SIM, PALM) as well as atomic force microscopy and Raman spectroscopy. Using examples of bistability in microbial populations as well as biofilm development and differentiation in bacterial and yeast consortia, we demonstrate the importance of microscopy...

  19. Advanced microscopy of microbial cells

    DEFF Research Database (Denmark)

    Haagensen, Janus Anders Juul; Regenberg, Birgitte; Sternberg, Claus

    2011-01-01

    microscopy, super-resolution optical microscopy (STED, SIM, PALM) as well as atomic force microscopy and Raman spectroscopy. Using examples of bistability in microbial populations as well as biofilm development and differentiation in bacterial and yeast consortia, we demonstrate the importance of microscopy...

  20. Reflected Glory

    Science.gov (United States)

    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

  1. Holographic microscopy for 3D tracking of bacteria

    Science.gov (United States)

    Nadeau, Jay; Cho, Yong Bin; El-Kholy, Marwan; Bedrossian, Manuel; Rider, Stephanie; Lindensmith, Christian; Wallace, J. Kent

    2016-03-01

    Understanding when, how, and if bacteria swim is key to understanding critical ecological and biological processes, from carbon cycling to infection. Imaging motility by traditional light microscopy is limited by focus depth, requiring cells to be constrained in z. Holographic microscopy offers an instantaneous 3D snapshot of a large sample volume, and is therefore ideal in principle for quantifying unconstrained bacterial motility. However, resolving and tracking individual cells is difficult due to the low amplitude and phase contrast of the cells; the index of refraction of typical bacteria differs from that of water only at the second decimal place. In this work we present a combination of optical and sample-handling approaches to facilitating bacterial tracking by holographic phase imaging. The first is the design of the microscope, which is an off-axis design with the optics along a common path, which minimizes alignment issues while providing all of the advantages of off-axis holography. Second, we use anti-reflective coated etalon glass in the design of sample chambers, which reduce internal reflections. Improvement seen with the antireflective coating is seen primarily in phase imaging, and its quantification is presented here. Finally, dyes may be used to increase phase contrast according to the Kramers-Kronig relations. Results using three test strains are presented, illustrating the different types of bacterial motility characterized by an enteric organism (Escherichia coli), an environmental organism (Bacillus subtilis), and a marine organism (Vibrio alginolyticus). Data processing steps to increase the quality of the phase images and facilitate tracking are also discussed.

  2. Globalization as a Driver or Bottleneck for Sustainable Development: Some Empirical, Cross-National Reflections on Basic Issues of International Health Policy and Management

    Science.gov (United States)

    Tausch, Arno

    2013-01-01

    Background: This article looks at the long-term, structural determinants of environmental and public health performance in the world system. Methods: In multiple standard ordinary least squares (OLS) regression models, we tested the effects of 26 standard predictor variables, including the ‘four freedoms’ of goods, capital, labour and services, on the following indicators of sustainable development and public health: avoiding net trade of ecological footprint global hectare (gha) per person; avoiding high carbon emissions per million US dollars GDP; avoiding high CO2 per capita (gha/cap); avoiding high ecological footprint per capita; avoiding becoming victim of natural disasters; a good performance on the Environmental Performance Index (EPI); a good performance on the Happy Life Years (HLYs) scale; and a good performance on the Happy Planet Index (HPI). Results: Our research showed that the apprehensions of quantitative research, critical of neo-liberal globalization, are fully vindicated by the significant negative environmental and public health effects of the foreign savings rate. High foreign savings are indeed a driver of global footprint, and are a blockade against a satisfactory HPI performance. The new international division of labour is one of the prime drivers of high CO2 per capita emissions. Multinational Corporation (MNC) penetration, the master variable of most quantitative dependency theories, blocks EPI and several other socially important processes. Worker remittances have a significant positive effect on the HPI, and HLYs. Conclusion: We re-analysed the solid macro-political and macro-sociological evidence on a global scale, published in the world’s leading peer-reviewed social science, ecological and public health journals, which seem to indicate that there are contradictions between unfettered globalization and unconstrained world economic openness and sustainable development and public health development. We suggest that there seems to

  3. Globalization as a driver or bottleneck for sustainable development: some empirical, cross-national reflections on basic issues of international health policy and management.

    Science.gov (United States)

    Tausch, Arno

    2013-08-01

    This article looks at the long-term, structural determinants of environmental and public health performance in the world system. In multiple standard ordinary least squares (OLS) regression models, we tested the effects of 26 standard predictor variables, including the 'four freedoms' of goods, capital, labour and services, on the following indicators of sustainable development and public health: avoiding net trade of ecological footprint global hectare (gha) per person; avoiding high carbon emissions per million US dollars GDP; avoiding high CO2 per capita (gha/cap); avoiding high ecological footprint per capita; avoiding becoming victim of natural disasters; a good performance on the Environmental Performance Index (EPI); a good performance on the Happy Life Years (HLYs) scale; and a good performance on the Happy Planet Index (HPI). Our research showed that the apprehensions of quantitative research, critical of neo-liberal globalization, are fully vindicated by the significant negative environmental and public health effects of the foreign savings rate. High foreign savings are indeed a driver of global footprint, and are a blockade against a satisfactory HPI performance. The new international division of labour is one of the prime drivers of high CO2 per capita emissions. Multinational Corporation (MNC) penetration, the master variable of most quantitative dependency theories, blocks EPI and several other socially important processes. Worker remittances have a significant positive effect on the HPI, and HLYs. We re-analysed the solid macro-political and macro-sociological evidence on a global scale, published in the world's leading peer-reviewed social science, ecological and public health journals, which seem to indicate that there are contradictions between unfettered globalization and unconstrained world economic openness and sustainable development and public health development. We suggest that there seems to be a strong interaction between 'transnational

  4. Globalization as a Driver or Bottleneck for Sustainable Development: Some Empirical, Cross-National Reflections on Basic Issues of International Health Policy and Management

    Directory of Open Access Journals (Sweden)

    Arno Tausch

    2013-01-01

    Full Text Available BackgroundThis article looks at the long-term, structural determinants of environmental and public health performance in the world system. MethodsIn multiple standard ordinary least squares (OLS regression models, we tested the effects of 26 standard predictor variables, including the ‘four freedoms’ of goods, capital, labour and services, on the following indicators of sustainable development and public health: avoiding net trade of ecological footprint global hectare (gha per person; avoiding high carbon emissions per million US dollars GDP; avoiding high CO2 per capita (gha/cap; avoiding high ecological footprint per capita; avoiding becoming victim of natural disasters; a good performance on the Environmental Performance Index (EPI; a good performance on the Happy Life Years (HLYs scale; and a good performance on the Happy Planet Index (HPI. ResultsOur research showed that the apprehensions of quantitative research, critical of neo-liberal globalization, are fully vindicated by the significant negative environmental and public health effects of the foreign savings rate. High foreign savings are indeed a driver of global footprint, and are a blockade against a satisfactory HPI performance. The new international division of labour is one of the prime drivers of high CO2 per capita emissions. Multinational Corporation (MNC penetration, the master variable of most quantitative dependency theories, blocks EPI and several other socially important processes. Worker remittances have a significant positive effect on the HPI, and HLYs. ConclusionWe re-analysed the solid macro-political and macro-sociological evidence on a global scale, published in the world’s leading peer-reviewed social science, ecological and public health journals, which seem to indicate that there are contradictions between unfettered globalization and unconstrained world economic openness and sustainable development and public health development. We suggest that there

  5. Polarized Light Microscopy

    Science.gov (United States)

    Frandsen, Athela F.

    2016-01-01

    Polarized light microscopy (PLM) is a technique which employs the use of polarizing filters to obtain substantial optical property information about the material which is being observed. This information can be combined with other microscopy techniques to confirm or elucidate the identity of an unknown material, determine whether a particular contaminant is present (as with asbestos analysis), or to provide important information that can be used to refine a manufacturing or chemical process. PLM was the major microscopy technique in use for identification of materials for nearly a century since its introduction in 1834 by William Fox Talbot, as other techniques such as SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared spectroscopy), XPD (X-ray Powder Diffraction), and TEM (Transmission Electron Microscopy) had not yet been developed. Today, it is still the only technique approved by the Environmental Protection Agency (EPA) for asbestos analysis, and is often the technique first applied for identification of unknown materials. PLM uses different configurations in order to determine different material properties. With each configuration additional clues can be gathered, leading to a conclusion of material identity. With no polarizing filter, the microscope can be used just as a stereo optical microscope, and view qualities such as morphology, size, and number of phases. With a single polarizing filter (single polars), additional properties can be established, such as pleochroism, individual refractive indices, and dispersion staining. With two polarizing filters (crossed polars), even more can be deduced: isotropy vs. anisotropy, extinction angle, birefringence/degree of birefringence, sign of elongation, and anomalous polarization colors, among others. With the use of PLM many of these properties can be determined in a matter of seconds, even for those who are not highly trained. McCrone, a leader in the field of polarized light microscopy, often

  6. International Society for Quality of Life Research commentary on the draft European Medicines Agency reflection paper on the use of patient-reported outcome (PRO) measures in oncology studies.

    Science.gov (United States)

    Kyte, Derek; Reeve, Bryce B; Efficace, Fabio; Haywood, Kirstie; Mercieca-Bebber, Rebecca; King, Madeleine T; Norquist, Josephine M; Lenderking, William R; Snyder, Claire; Ring, Lena; Velikova, Galina; Calvert, Melanie

    2016-02-01

    In 2014, the European Medicines Agency (EMA) released for comment a draft reflection paper on the use of patient-reported outcome (PRO) measures in oncology studies. A twelve-member International Society for Quality of Life Research (ISOQOL) taskforce was convened to coordinate the ISOQOL response. Twenty-one ISOQOL members provided detailed comments and suggestions on the paper: 81 % from academia and 19 % from industry. Taskforce members consolidated and further refined these comments and shared the recommendations with the wider ISOQOL membership. A final response was submitted to the EMA in November 2014. The impending publication of the EMA reflection paper presents a valuable opportunity for ISOQOL to comment on the current direction of EMA PRO guidance and strategy. The EMA paper, although focused on cancer, could serve as a model for using PROs in other conditions, as it provides a useful update surrounding some of the design issues common to all trial research including PRO endpoints. However, we believe there are a number of additional areas in need of greater consideration. The purpose of this commentary is therefore to highlight the strengths of this timely and potentially useful document, but also to outline areas that may warrant further discussion.

  7. Multimodal hyperspectral optical microscopy

    Science.gov (United States)

    Novikova, Irina V.; Smallwood, Chuck R.; Gong, Yu; Hu, Dehong; Hendricks, Leif; Evans, James E.; Bhattarai, Ashish; Hess, Wayne P.; El-Khoury, Patrick Z.

    2017-11-01

    We describe a unique approach to hyperspectral optical microscopy, herein achieved by coupling a hyperspectral imager to various optical microscopes. Hyperspectral fluorescence micrographs of isolated fluorescent beads are first employed to ensure spectral calibration of our detector and to gauge the attainable spatial resolution of our measurements. Different science applications of our instrument are then described. Spatially over-sampled absorption spectroscopy of a single lipid (18:1 Liss Rhod PE) layer reveals that optical densities on the order of 10-3 can be resolved by spatially averaging the recorded optical signatures. This is followed by three applications in the general areas of plasmonics and bioimaging. Notably, we deploy hyperspectral absorption microscopy to identify and image pigments within a simple biological system, namely, a single live Tisochrysis lutea cell. Overall, this work paves the way for multimodal spectral imaging measurements spanning the realms of several scientific disciplines.

  8. Electron microscopy and diffraction

    International Nuclear Information System (INIS)

    Gjoennes, J.; Olsen, A.

    1986-01-01

    This report is a description of research activities and plans at the electron microscopy laboratorium, Physics Department, University of Oslo. Since the first electron microscope was installed in 1968, the research has covered inorganic structures, physical metallurgy, as well as theory of electron scattering and the development of methods in this field. The current plans involve efforts in the development of crystallographic and spectroscopic methods

  9. Deep Learning Microscopy

    KAUST Repository

    Rivenson, Yair

    2017-05-12

    We demonstrate that a deep neural network can significantly improve optical microscopy, enhancing its spatial resolution over a large field-of-view and depth-of-field. After its training, the only input to this network is an image acquired using a regular optical microscope, without any changes to its design. We blindly tested this deep learning approach using various tissue samples that are imaged with low-resolution and wide-field systems, where the network rapidly outputs an image with remarkably better resolution, matching the performance of higher numerical aperture lenses, also significantly surpassing their limited field-of-view and depth-of-field. These results are transformative for various fields that use microscopy tools, including e.g., life sciences, where optical microscopy is considered as one of the most widely used and deployed techniques. Beyond such applications, our presented approach is broadly applicable to other imaging modalities, also spanning different parts of the electromagnetic spectrum, and can be used to design computational imagers that get better and better as they continue to image specimen and establish new transformations among different modes of imaging.

  10. Electrochemical force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kalinin, Sergei V.; Jesse, Stephen; Collins, Liam F.; Rodriguez, Brian J.

    2017-01-10

    A system and method for electrochemical force microscopy are provided. The system and method are based on a multidimensional detection scheme that is sensitive to forces experienced by a biased electrode in a solution. The multidimensional approach allows separation of fast processes, such as double layer charging, and charge relaxation, and slow processes, such as diffusion and faradaic reactions, as well as capturing the bias dependence of the response. The time-resolved and bias measurements can also allow probing both linear (small bias range) and non-linear (large bias range) electrochemical regimes and potentially the de-convolution of charge dynamics and diffusion processes from steric effects and electrochemical reactivity.

  11. Deep Learning Microscopy

    OpenAIRE

    Rivenson, Yair; Gorocs, Zoltan; Gunaydin, Harun; Zhang, Yibo; Wang, Hongda; Ozcan, Aydogan

    2017-01-01

    We demonstrate that a deep neural network can significantly improve optical microscopy, enhancing its spatial resolution over a large field-of-view and depth-of-field. After its training, the only input to this network is an image acquired using a regular optical microscope, without any changes to its design. We blindly tested this deep learning approach using various tissue samples that are imaged with low-resolution and wide-field systems, where the network rapidly outputs an image with rem...

  12. Physical foundations of electron microscopy

    International Nuclear Information System (INIS)

    Alexander, H.

    1997-01-01

    The following topics were dealt with: Physical foundations, dynamic theory of diffraction contrasts, dynamic theory of electron diffraction, electron diffraction on crystals with defects, high-resolution electron microscopy, analytical electron microscopy

  13. A Reflective Look at Reflecting Teams

    Science.gov (United States)

    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…

  14. Membranes and Fluorescence microscopy

    DEFF Research Database (Denmark)

    Bagatolli, Luis

    2009-01-01

    Fluorescence spectroscopy-based techniques using conventional fluorimeters have been extensively applied since the late 1960s to study different aspects of membrane-related phenomena, i.e., mainly relating to lipid-lipid and lipid-protein (peptide) interactions. Even though fluorescence spectrosc......Fluorescence spectroscopy-based techniques using conventional fluorimeters have been extensively applied since the late 1960s to study different aspects of membrane-related phenomena, i.e., mainly relating to lipid-lipid and lipid-protein (peptide) interactions. Even though fluorescence...... spectroscopy approaches provide very valuable structurally and dynamically related information on membranes, they generally produce mean parameters from data collected on bulk solutions of many vesicles and lack direct information on the spatial organization at the level of single membranes, a quality that can...... be provided by microscopy-related techniques. In this chapter, I will attempt to summarize representative examples concerning how microscopy (which provides information on membrane lateral organization by direct visualization) and spectroscopy techniques (which provides information about molecular interaction...

  15. Correlative Stochastic Optical Reconstruction Microscopy and Electron Microscopy

    Science.gov (United States)

    Kim, Doory; Deerinck, Thomas J.; Sigal, Yaron M.; Babcock, Hazen P.; Ellisman, Mark H.; Zhuang, Xiaowei

    2015-01-01

    Correlative fluorescence light microscopy and electron microscopy allows the imaging of spatial distributions of specific biomolecules in the context of cellular ultrastructure. Recent development of super-resolution fluorescence microscopy allows the location of molecules to be determined with nanometer-scale spatial resolution. However, correlative super-resolution fluorescence microscopy and electron microscopy (EM) still remains challenging because the optimal specimen preparation and imaging conditions for super-resolution fluorescence microscopy and EM are often not compatible. Here, we have developed several experiment protocols for correlative stochastic optical reconstruction microscopy (STORM) and EM methods, both for un-embedded samples by applying EM-specific sample preparations after STORM imaging and for embedded and sectioned samples by optimizing the fluorescence under EM fixation, staining and embedding conditions. We demonstrated these methods using a variety of cellular targets. PMID:25874453

  16. Analytics on Transmission Electron Microscopy

    International Nuclear Information System (INIS)

    Keum, Dong Hwa; Kim, Geung Ho; Lee, Hwak Ju and others

    1996-06-01

    This book gives descriptions of transmission electron microscopy, which deals with electron microscopy and materials science, history of electron microscopy, application of analytics on transmission electron microscopy, machine requirement of transmission electron microscopy like electron gun and TEM image and function, crystal diffraction, electron diffraction, Kikuchi's diffraction figure, analysis of diffraction figure, contrast of TEM image like absorption contrast, and phase contrast, Fresnel's diffraction and TEM contrast, thickness fringe, column approximation, analysis of diffraction contrast, image simulation, and electron energy loss spectrometry.

  17. High resolution, high speed ultrahigh vacuum microscopy

    International Nuclear Information System (INIS)

    Poppa, Helmut

    2004-01-01

    The history and future of transmission electron microscopy (TEM) is discussed as it refers to the eventual development of instruments and techniques applicable to the real time in situ investigation of surface processes with high resolution. To reach this objective, it was necessary to transform conventional high resolution instruments so that an ultrahigh vacuum (UHV) environment at the sample site was created, that access to the sample by various in situ sample modification procedures was provided, and that in situ sample exchanges with other integrated surface analytical systems became possible. Furthermore, high resolution image acquisition systems had to be developed to take advantage of the high speed imaging capabilities of projection imaging microscopes. These changes to conventional electron microscopy and its uses were slowly realized in a few international laboratories over a period of almost 40 years by a relatively small number of researchers crucially interested in advancing the state of the art of electron microscopy and its applications to diverse areas of interest; often concentrating on the nucleation, growth, and properties of thin films on well defined material surfaces. A part of this review is dedicated to the recognition of the major contributions to surface and thin film science by these pioneers. Finally, some of the important current developments in aberration corrected electron optics and eventual adaptations to in situ UHV microscopy are discussed. As a result of all the path breaking developments that have led to today's highly sophisticated UHV-TEM systems, integrated fundamental studies are now possible that combine many traditional surface science approaches. Combined investigations to date have involved in situ and ex situ surface microscopies such as scanning tunneling microscopy/atomic force microscopy, scanning Auger microscopy, and photoemission electron microscopy, and area-integrating techniques such as x-ray photoelectron

  18. Photovoltaic module with light reflecting backskin

    Science.gov (United States)

    Gonsiorawski, Ronald C.

    2007-07-03

    A photovoltaic module comprises electrically interconnected and mutually spaced photovoltaic cells that are encapsulated by a light-transmitting encapsulant between a light-transparent front cover and a back cover, with the back cover sheet being an ionomer/nylon alloy embossed with V-shaped grooves running in at least two directions and coated with a light reflecting medium so as to provide light-reflecting facets that are aligned with the spaces between adjacent cells and oriented so as to reflect light falling in those spaces back toward said transparent front cover for further internal reflection onto the solar cells, whereby substantially all of the reflected light will be internally reflected from said cover sheet back to the photovoltaic cells, thereby increasing the current output of the module. The internal reflector improves power output by as much as 67%.

  19. Ethical reflection and psychotherapy.

    Science.gov (United States)

    Vyskocilová, Jana; Prasko, Jan

    2013-01-01

    Theories of ethics and ethical reflection may be applied to both theory and practice in psychotherapy. There is a natural affinity between ethics and psychotherapy. Psychotherapy practice is concerned with human problems, dilemmas and emotions related to both one's own and other people's values. Ethics is also concerned with dilemmas in human thinking and with how these dilemmas reflect other individuals' values. Philosophical reflection itself is not a sufficient basis for the ethics of psychotherapy but it may aid in exploring attitudes related to psychotherapy, psychiatry and health care. PubMed, Web of Science and Scopus databases were searched for articles containing the keywords "psychotherapy", "ethics", "therapeutic relationship" and "supervision". The search was conducted by repeating the terms in various combinations without language or time restrictions. Also included were data from monographs cited in reviews. The resulting text is a review with conclusions concerning ethical aspects of psychotherapy. The ability to behave altruistically, sense for justice and reciprocity and mutual help are likely to be genetically determined as dispositions to be later developed by upbringing or to be formed or deformed by upbringing. Early experiences lead to formation of ethical attitudes which are internalized and then applied to both one's own and other people's behavior. Altruistic behavior has a strong impact on an individual's health and its acceptance may positively influence the pathophysiological mechanisms underlying numerous diseases. Ethical theory and reflection, however, may be applied to both theory and practice of psychotherapy in a conscious, targeted and thoughtful manner. In everyday practice, psychotherapists and organizations must necessarily deal with conscious conflicts between therapeutic possibilities, clients' wishes, their own as well as clients' ideas and the real world. Understanding one's own motives in therapy is one of the aims of a

  20. Waveguide optical microscopy

    Science.gov (United States)

    Egorov, Alexandre A.

    1997-08-01

    The theoretical aspects of the light scattering on the statistical irregularities of the planar optical waveguide are described. The analysis of direct and inverse light scattering problems is accomplished. The theoretical investigation predicts: the lateral resolution can attain approximately 20 nm and the vertical resolution (in rms height) can attain approximately 1 angstrom. The limiting lateral resolution is a approximately 15-times less than Abbe's diffraction limit. Thus the superresolution may be accomplished by the waveguide optical microscopy (WOM). The increasing of WOM's resolution depends on a-priori information of the irregularities and on a sufficiently high signal-to-noise ratio. A possible using of WOM for bioecological researchers has been mentioned.

  1. Radioactive ion microscopy

    International Nuclear Information System (INIS)

    Johnson, S.A.

    1980-01-01

    A novel approach has been studied for the characterization of specimens with a spatial resolution at the micron level. The technique dubbed Radioactive Ion Microscopy, (RIM) uses a beam of radioactive ions, specifically tritium ions, of sufficient energy to pass through a thick specimen (e.g. greater than or equal to 10 μm). After passage through the object, the ions are implanted in a stack of thin mylar sheets (1.5 microns thick). Their rest position is proportional to the thickness and the density of the sample transversed. The location of the radioactive species can be pinpointed by autoradiographing the successive mylar foils. The radiographs are photographed and converted into digital data which is used to generate a density map of the object. From these plots, physical and chemical features may be deduced. The feasibility of RIM has been demonstrated with specimen images obtained from different objects exposed to a 3 MeV 3 H + beam. The specimens used included metal grids to examine spatial resolution and a series of biological samples (cork, wood, mosquito wing) to explore the performance and applicability of RIM. On these samples, which were 10 to 30 microns thick with surface areas of up to 1 cm 2 , a lateral resolution of approx. 1.5 microns was achieved. A depth resolution or sensitivity to density gradients of 0.2 mg/cm 2 was obtained. These detailed specimen images can be obtained with low beam exposures, e.g., in the case of tritium approx. 6 x 10 10 ions/cm 2 must be implanted, which corresponds to an irradiation of approx. 10 pA/cm 2 for 1000 s. The corresponding low radiation doses and minimal heat dissipation render RIM well suited for biological specimens. In comparison to light microscopy, RIM features enhanced microscopic capabilities as it can handle objects that are at the same time opaque to light, thick (up to tens of microns), and fragile

  2. Extraterrestrial optical microscopy.

    Science.gov (United States)

    Soffen, G A

    1969-07-01

    An examination of the literature concerned with the use of microscopy for planetary investigation reveals a serious deficiency of current efforts. Many scientists have recommended the use of a microscope for planetary investigation [Biology and the Exploration of Mars, C. S. Pittendrigh, W. Vishniac, and J. P. T. Pearman, Eds. (National Academy of Science-National Research Council, Washington, D. C., 1966), (a) D. Mazia, p. 31; (b) J. Lederberg, p. 137; (c) S. Fox, pp. 219, 226; (d) D. Glaser, p. 326; (e) D. Glaser, J. McCarthy, and M. Minsky, pp. 333, 341; (f) D. G. Rea, pp. 347-426; (g) P. G. Conger, pp. 409-414; (h) M. H. Fernandez, pp. 414-425; (i) D. Schwartz, pp.425-426 . H. P. Klein, Some Biological Problems in the Search for Extraterrestrial Life (American Astronautical Society, Washington, D. C., 1968).] but few are involved in developing the experiment. Since this is a particularly timely period for the preparation of planetary lander experiments, the reasons for this lack of effort would appear to be limited resources or an unclear course of action, rather than lack of interest. Microscopy used for planetary investigation is chiefly the interest of the biologist and the mineralogist. In both cases the desire to use magnifying optics in order to observe objects of submillimeter size is based upon the rich body of knowledge we have acquired from observing the terrestrial microcosm. In addition to purely imaging, certain special optical techniques, e.g., polarimetry, colorimetry, phase contrast, etc., can be used to enhance the interpretation of microscopic imaging data. This interaction of the optical with the chemical or structural aspects of nature can be used to great advantage in the exploration of extraterrestrial biology and mineralogy.

  3. Photoemission electron microscopy and scanning electron microscopy of Magnetospirillum magnetotacticum’s magnetosome chains

    Energy Technology Data Exchange (ETDEWEB)

    Keutner, Christoph [Technische Univ. Dortmund, Dortmung (Germany); von Bohlen, Alex [Leibniz-Institut fur Analytische Wissenschaften, Dortmund (Germany); Berges, Ulf [Technische Univ. Dortmund, Dortmung (Germany); Espeter, Philipp [Technische Univ. Dortmund, Dortmung (Germany); Schneider, Claus M. [Peter Grunberg Institut, Julich (Germany); Westphal, Carsten [Technische Univ. Dortmund, Dortmung (Germany)

    2014-10-07

    Magnetotactic bacteria are of great interdisciplinary interest, since a vast field of applications from magnetic recording media to medical nanorobots is conceivable. A key feature for a further understanding is the detailed knowledge about the magnetosome chain within the bacteria. We report on two preparation procedures suitable for UHV experiments in reflective geometry. Further, we present the results of scanning electron microscopy, as well as the first photoemission electron microscopy experiments, both accessing the magnetosomes within intact magnetotactic bacteria and compare these to scanning electron microscopy data from the literature. From the images, we can clearly identify individual magnetosomes within their chains.

  4. Gamma camera with reflectivity mask

    International Nuclear Information System (INIS)

    Stout, K.J.

    1980-01-01

    In accordance with the present invention there is provided a radiographic camera comprising: a scintillator; a plurality of photodectors positioned to face said scintillator; a plurality of masked regions formed upon a face of said scintillator opposite said photdetectors and positioned coaxially with respective ones of said photodetectors for decreasing the amount of internal reflection of optical photons generated within said scintillator. (auth)

  5. Models og International Entrepreneurship

    DEFF Research Database (Denmark)

    Rask, Morten; Servais, Per

    2015-01-01

    on International Entrepreneurship, and specifically but not exclusively, International New Ventures (INVs). The three resulting ‘meta-models’ depict the activities and loci of such firms, the motivating factors that give rise to such firms and their growth modalities and strategies. These models reflect the merger...... of entrepreneurship and international business into the field of international entrepreneurship....

  6. Advanced spinning disk-TIRF microscopy for faster imaging of the cell interior and the plasma membrane.

    Science.gov (United States)

    Zobiak, Bernd; Failla, Antonio Virgilio

    2018-03-01

    Understanding the cellular processes that occur between the cytosol and the plasma membrane is an important task for biological research. Till now, however, it was not possible to combine fast and high-resolution imaging of both the isolated plasma membrane and the surrounding intracellular volume. Here, we demonstrate the combination of fast high-resolution spinning disk (SD) and total internal reflection fluorescence (TIRF) microscopy for specific imaging of the plasma membrane. A customised SD-TIRF microscope was used with specific design of the light paths that allowed, for the first time, live SD-TIRF experiments at high acquisition rates. A series of experiments is shown to demonstrate the feasibility and performance of our setup. © 2017 The Authors. Journal of Microscopy published by JohnWiley & Sons Ltd on behalf of Royal Microscopical Society.

  7. Virtual microscopy in pathology education.

    Science.gov (United States)

    Dee, Fred R

    2009-08-01

    Technology for acquisition of virtual slides was developed in 1985; however, it was not until the late 1990s that desktop computers had enough processing speed to commercialize virtual microscopy and apply the technology to education. By 2000, the progressive decrease in use of traditional microscopy in medical student education had set the stage for the entry of virtual microscopy into medical schools. Since that time, it has been successfully implemented into many pathology courses in the United States and around the world, with surveys indicating that about 50% of pathology courses already have or expect to implement virtual microscopy. Over the last decade, in addition to an increasing ability to emulate traditional microscopy, virtual microscopy has allowed educators to take advantage of the accessibility, efficiency, and pedagogic versatility of the computer and the Internet. The cost of virtual microscopy in education is now quite reasonable after taking into account replacement cost for microscopes, maintenance of glass slides, and the fact that 1-dimensional microscope space can be converted to multiuse computer laboratories or research. Although the current technology for implementation of virtual microscopy in histopathology education is very good, it could be further improved upon by better low-power screen resolution and depth of field. Nevertheless, virtual microscopy is beginning to play an increasing role in continuing education, house staff education, and evaluation of competency in histopathology. As Z-axis viewing (focusing) becomes more efficient, virtual microscopy will also become integrated into education in cytology, hematology, microbiology, and urinalysis.

  8. Second-harmonic scanning optical microscopy of poled silica waveguides

    DEFF Research Database (Denmark)

    Pedersen, Kjeld; Bozhevolnyi, Sergey I.; Arentoft, Jesper

    2000-01-01

    Second-harmonic scanning optical microscopy (SHSOM) is performed on electric-field poled silica-based waveguides. Two operation modes of SHSOM are considered. Oblique transmission reflection and normal reflection modes are used to image the spatial distribution of nonlinear susceptibilities...... and limitations of the two operation modes when used for SHSOM studies of poled silica-based waveguides are discussed. The influence of surface defects on the resulting second-harmonic images is also considered. ©2000 American Institute of Physics....

  9. Hydrodynamic force microscopy

    Science.gov (United States)

    Ulrich, Elaine Schmid

    Microfluidic networks and microporous materials have long been of interest in areas such as hydrology, petroleum engineering, chemical and electrochemical engineering, medicine and biochemical engineering. With the emergence of new processes in gas separation, cell sorting, ultrafiltration, and advanced materials synthesis, the importance of building a better qualitative and quantitative understanding of these key technologies has become apparent. However, microfluidic measurement and theory is still relatively underdeveloped, presenting a significant obstacle to the systematic design of microfluidic devices and materials. Theoretical challenges arise from the breakdown of classical viscous flow models as the flow dimensions approach the mean free path of individual molecules. Experimental challenges arise from the lack of flow profilometry techniques at sub-micron length scales. Here we present an extension of scanning probe microscopy techniques, which we have termed Hydrodynamic Force Microscopy (HFM). HFM exploits fluid drag to profile microflows and to map the permeability of microporous materials. In this technique, an atomic force microscope (AFM) cantilever is scanned close to a microporous sample surface. The hydrodynamic interactions arising from a pressure-driven flow through the sample are then detected by mapping the deflection of an AFM cantilever. For gas flows at atmospheric pressure, HFM has been shown to achieve a velocity sensitivity of 1 cm/s with a spatial resolution of ˜ 10 nm. This compares very favorably to established techniques such as hot-wire and laser Doppler anemometry, whose spatial resolutions typically exceed 1 mum and which may rely on the use of tracer particles or flow markers1. We demonstrate that HFM can successfully profile Poiseuille flows inside pores as small as 100 nm and can distinguish Poiseuille flow from uniform flow for short entry lengths. HFM detection of fluid jets escaping from porous samples can also reveal a

  10. Relationship between microstructure of the skin surface and surface reflection based on geometric optics.

    Science.gov (United States)

    Yoshida, Kenichiro; Miyaki, Masahiro; Ojima, Nobutoshi; Iwata, Kayoko

    2012-06-01

    The behavior of reflected light in skin affects skin appearance and provides clues as to the internal condition of the skin. Surface topography is one of the central physical factors contributing to surface reflection. We tried to clarify the relationship between microstructure of the skin surface and surface reflection based on geometric optics. Microstructures and surface reflections in the left cheeks of adult females were evaluated. Skin topography was acquired measuring replicas using confocal laser microscopy. Surface topography was used to calculate arithmetical mean deviation of the surface (S(a)), and geometric index from gradient of the surface (S(grad)), which is expected to correlate with the directionality of surface reflection (DoSR) based on geometric optics. A surface reflection image was acquired from differently polarized pictures of a face, and the index of surface reflection (I(obs)) was calculated as the average pixel value of the area of shine. Correlations between indices were then evaluated. S(grad) and S(a) showed significant correlation (preflection from the reflection model than S(a). In addition, S(grad) can explain differences in DoSR for some panelists even in the case of an identical S(a). The topographic element involved in DoSR was extracted from height mapping. S(grad) reflects the ratio of flat area, offering a more effective indicator than S(a) for distinguishing topographic characteristics with respect to surface reflection. Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  11. Fast benchtop fabrication of laminar flow chambers for advanced microscopy techniques.

    Directory of Open Access Journals (Sweden)

    David S Courson

    2009-08-01

    Full Text Available Fluid handling technology is acquiring an ever more prominent place in laboratory science whether it is in simple buffer exchange systems, perfusion chambers, or advanced microfluidic devices. Many of these applications remain the providence of laboratories at large institutions with a great deal of expertise and specialized equipment. Even with the expansion of these techniques, limitations remain that frequently prevent the coupling of controlled fluid flow with other technologies, such as coupling microfluidics and high-resolution position and force measurements by optical trapping microscopy.Here we present a method for fabrication of multiple-input laminar flow devices that are optically clear [glass] on each face, chemically inert, reusable, inexpensive, and can be fabricated on the benchtop in approximately one hour. Further these devices are designed to allow flow regulation by a simple gravity method thus requiring no specialized equipment to drive flow. Here we use these devices to perform total internal reflection fluorescence microscopy measurements as well as position sensitive optical trapping experiments.Flow chamber technology needs to be more accessible to the general scientific community. The method presented here is versatile and robust. These devices use standard slides and coverslips making them compatible with nearly all types and models of light microscopes. These devices meet the needs of groups doing advanced optical trapping experiments, but could also be adapted by nearly any lab that has a function for solution flow coupled with microscopy.

  12. Grid-enhanced X-ray coded aperture microscopy with polycapillary optics.

    Science.gov (United States)

    Sowa, Katarzyna M; Last, Arndt; Korecki, Paweł

    2017-03-21

    Polycapillary devices focus X-rays by means of multiple reflections of X-rays in arrays of bent glass capillaries. The size of the focal spot (typically 10-100 μm) limits the resolution of scanning, absorption and phase-contrast X-ray imaging using these devices. At the expense of a moderate resolution, polycapillary elements provide high intensity and are frequently used for X-ray micro-imaging with both synchrotrons and X-ray tubes. Recent studies have shown that the internal microstructure of such an optics can be used as a coded aperture that encodes high-resolution information about objects located inside the focal spot. However, further improvements to this variant of X-ray microscopy will require the challenging fabrication of tailored devices with a well-defined capillary microstructure. Here, we show that submicron coded aperture microscopy can be realized using a periodic grid that is placed at the output surface of a polycapillary optics. Grid-enhanced X-ray coded aperture microscopy with polycapillary optics does not rely on the specific microstructure of the optics but rather takes advantage only of its focusing properties. Hence, submicron X-ray imaging can be realized with standard polycapillary devices and existing set-ups for micro X-ray fluorescence spectroscopy.

  13. Planar Reflection of Gaseous Detonations

    Science.gov (United States)

    Damazo, Jason Scott

    Pipes containing flammable gaseous mixtures may be subjected to internal detonation. When the detonation normally impinges on a closed end, a reflected shock wave is created to bring the flow back to rest. This study built on the work of Karnesky (2010) and examined deformation of thin-walled stainless steel tubes subjected to internal reflected gaseous detonations. A ripple pattern was observed in the tube wall for certain fill pressures, and a criterion was developed that predicted when the ripple pattern would form. A two-dimensional finite element analysis was performed using Johnson-Cook material properties; the pressure loading created by reflected gaseous detonations was accounted for with a previously developed pressure model. The residual plastic strain between experiments and computations was in good agreement. During the examination of detonation-driven deformation, discrepancies were discovered in our understanding of reflected gaseous detonation behavior. Previous models did not accurately describe the nature of the reflected shock wave, which motivated further experiments in a detonation tube with optical access. Pressure sensors and schlieren images were used to examine reflected shock behavior, and it was determined that the discrepancies were related to the reaction zone thickness extant behind the detonation front. During these experiments reflected shock bifurcation did not appear to occur, but the unfocused visualization system made certainty impossible. This prompted construction of a focused schlieren system that investigated possible shock wave-boundary layer interaction, and heat-flux gauges analyzed the boundary layer behind the detonation front. Using these data with an analytical boundary layer solution, it was determined that the strong thermal boundary layer present behind the detonation front inhibits the development of reflected shock wave bifurcation.

  14. Ultrafast scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Botkin, D.A. [California Univ., Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  15. Magnetic Resonance Force Microscopy System

    Data.gov (United States)

    Federal Laboratory Consortium — The Magnetic Resonance Force Microscopy (MRFM) system, developed by ARL, is the world's most sensitive nuclear magnetic resonance (NMR) spectroscopic analysis tool,...

  16. NDE Acoustic Microscopy Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The purpose is to develop advanced, more effective high-resolution micro-NDE materials characterization methods using scanning acoustic microscopy. The laboratory's...

  17. Active voltage contrast imaging of cross-sectional surface of multilayer ceramic capacitor using helium ion microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, C., E-mail: SAKAI.Chikako@nims.go.jp; Ishida, N.; Masuda, H.; Nagano, S.; Kitahara, M.; Fujita, D. [National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan); Ogata, Y. [TAIYO YUDEN CO., LTD., Takasaki-shi, Gunma 370-3347 (Japan)

    2016-08-01

    We studied active voltage contrast (AVC) imaging using helium ion microscopy (HIM). We observed secondary electron (SE) images of the cross-sectional surface of multilayer ceramic capacitors (MLCCs) with and without a voltage applied to the internal electrodes. When no voltage was applied, we obtained an image reflecting the material contrast between the Ni internal electrode region and the BaTiO{sub 3} dielectric region of the cross-sectional surface of the MLCC. When a voltage was applied, the electrical potential difference between the grounded and the positively biased internal electrodes affected the contrast (voltage contrast). Moreover, attenuation of the SE intensity from the grounded to the positively biased internal electrodes was observed in the dielectric region. Kelvin probe force microscopy (KPFM) measurements of the contact potential difference (CPD) were performed on the same sample. By using the AVC image from the HIM observation and the CPD image from the KPFM measurement, we could quantitatively evaluate the electrical potential. We think that the results of this study will lead to an expansion in the number of applications of HIM.

  18. Super-resolution and super-localization microscopy: A novel tool for imaging chemical and biological processes

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Bin [Iowa State Univ., Ames, IA (United States)

    2015-01-01

    Optical microscopy imaging of single molecules and single particles is an essential method for studying fundamental biological and chemical processes at the molecular and nanometer scale. The best spatial resolution (~ λ/2) achievable in traditional optical microscopy is governed by the diffraction of light. However, single molecule-based super-localization and super-resolution microscopy imaging techniques have emerged in the past decade. Individual molecules can be localized with nanometer scale accuracy and precision for studying of biological and chemical processes.This work uncovered the heterogeneous properties of the pore structures. In this dissertation, the coupling of molecular transport and catalytic reaction at the single molecule and single particle level in multilayer mesoporous nanocatalysts was elucidated. Most previous studies dealt with these two important phenomena separately. A fluorogenic oxidation reaction of non-fluorescent amplex red to highly fluorescent resorufin was tested. The diffusion behavior of single resorufin molecules in aligned nanopores was studied using total internal reflection fluorescence microscopy (TIRFM).

  19. Reflective Self-Regenerative Systems Architecture Study

    National Research Council Canada - National Science Library

    Pu, Carlton; Blough, Douglas

    2006-01-01

    In this study, we develop the Reflective Self-Regenerative Systems (RSRS) architecture in detail, describing the internal structure of each component and the mutual invocations among the components...

  20. Vibrational phase contrast CARS microscopy

    NARCIS (Netherlands)

    Jurna, M.

    2010-01-01

    This thesis describes a new technique that improves specificity, selectivity and sensitivity in coherent anti-Stokes Raman scattering (CARS) microscopy. CARS microscopy is a nonlinear optical technique that utilizes specific bonds of molecules, sometimes referred to as the `fingerprint' of a

  1. Advanced computing in electron microscopy

    CERN Document Server

    Kirkland, Earl J

    2010-01-01

    This book features numerical computation of electron microscopy images as well as multislice methods High resolution CTEM and STEM image interpretation are included in the text This newly updated second edition will bring the reader up to date on new developments in the field since the 1990's The only book that specifically addresses computer simulation methods in electron microscopy

  2. Electronic Blending in Virtual Microscopy

    Science.gov (United States)

    Maybury, Terrence S.; Farah, Camile S.

    2010-01-01

    Virtual microscopy (VM) is a relatively new technology that transforms the computer into a microscope. In essence, VM allows for the scanning and transfer of glass slides from light microscopy technology to the digital environment of the computer. This transition is also a function of the change from print knowledge to electronic knowledge, or as…

  3. PREFACE: 18th Microscopy of Semiconducting Materials Conference (MSM XVIII)

    Science.gov (United States)

    Walther, T.; Hutchison, John L.

    2013-11-01

    dislocation core structures at atomic resolution. Conference photograph Figure 1. Conference photo taken by JLH inside St Catherine's College Each of the 49 manuscripts submitted for publication in this proceedings volume has been independently reviewed, most by two reviewers, and revised where necessary before being accepted for publication. The Editors are grateful to the following colleagues for their rapid and careful reviewing of manuscripts: R Beanland, C B Boothroyd, P D Brown, D Cherns, A J Craven, K Durose, C J Humphreys, U Kaiser, L Lari, G A Moebus, A G Norman, P Pecz, I M Ross, D J Smith and K Tillmann. Poster prizes were awarded to the following students: joint first prizes to Robert Schewski, Leibniz-Institut für Kristallzüchtung, Berlin and Xiaowei Wu, Rensselaer Polytechnic Institute, Troy; and joint second prizes to Tyche Perkisas, University of Antwerp and Adi Pantzer, Ben Gurion University of the Negev. These presentations indicated both a broad range of microscopy techniques and materials issues covered as well as the excellent standard of microscopy now being achieved by younger scientists. They also reflected the internationality of the attending scientists. On the evening of 9 April 2013, the RMS Annual Materials Lecture was delivered by Professor Sir Colin J Humphreys from the University of Cambridge. Colin's highly entertaining talk on 'How microscopy and semiconductors can help to solve some major world problems' spanned a very broad range, from detailed atomistic investigation of lattice defects in gallium nitride layers by transmission electron microscopy, to the production of new light emitting diodes and its impact on reducing both our electricity bills and the effect of global warming. Entertainment during the conference dinner was provided by the Ariella String Trio, and during the meal we held a friendly competition in which teams had to recognise invited speakers and organisers from photos of them as babies or young children. The organisers

  4. Microscopy techniques in flavivirus research.

    Science.gov (United States)

    Chong, Mun Keat; Chua, Anthony Jin Shun; Tan, Terence Tze Tong; Tan, Suat Hoon; Ng, Mah Lee

    2014-04-01

    The Flavivirus genus is composed of many medically important viruses that cause high morbidity and mortality, which include Dengue and West Nile viruses. Various molecular and biochemical techniques have been developed in the endeavour to study flaviviruses. However, microscopy techniques still have irreplaceable roles in the identification of novel virus pathogens and characterization of morphological changes in virus-infected cells. Fluorescence microscopy contributes greatly in understanding the fundamental viral protein localizations and virus-host protein interactions during infection. Electron microscopy remains the gold standard for visualizing ultra-structural features of virus particles and infected cells. New imaging techniques and combinatory applications are continuously being developed to push the limit of resolution and extract more quantitative data. Currently, correlative live cell imaging and high resolution three-dimensional imaging have already been achieved through the tandem use of optical and electron microscopy in analyzing biological specimens. Microscopy techniques are also used to measure protein binding affinities and determine the mobility pattern of proteins in cells. This chapter will consolidate on the applications of various well-established microscopy techniques in flavivirus research, and discuss how recently developed microscopy techniques can potentially help advance our understanding in these membrane viruses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. PROTON MICROSCOPY AT FAIR

    International Nuclear Information System (INIS)

    Merrill, F. E.; Mariam, F. G.; Golubev, A. A.; Turtikov, V. I.; Varentsov, D.

    2009-01-01

    Proton radiography was invented in the 1990's at Los Alamos National Laboratory (LANL) as a diagnostic to study dynamic material properties under extreme pressures, strain and strain rate. Since this time hundreds of dynamic proton radiography experiments have been performed at LANL and a facility has been commissioned at the Institute for Theoretical and Experimental Physics (ITEP) in Russia for similar applications in dynamic material studies. Recently an international effort has investigated a new proton radiography capability for the study of dynamic material properties at the Facility for Anti-proton and Ion Research (FAIR) located in Darmstadt, Germany. This new Proton microscope for FAIR(PRIOR) will provide radiographic imaging of dynamic systems with unprecedented spatial, temporal and density resolution, resulting in a window for understanding dynamic material properties at new length scales. It is also proposed to install the PRIOR system at the GSI Helmholtzzentrum fuer Schwerionenforschung before installation at FAIR for dynamic experiments with different drivers including high explosives, pulsed power and lasers. The design of the proton microscope and expected radiographic performance is presented.

  6. Reflectivity, Reflexivity and Situated Reflective Practice

    Science.gov (United States)

    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 here…

  7. Reflection Positive Doubles

    OpenAIRE

    Jaffe, Arthur; Janssens, Bas

    2016-01-01

    Here we introduce reflection positive doubles, a general framework for reflection positivity, covering a wide variety of systems in statistical physics and quantum field theory. These systems may be bosonic, fermionic, or parafermionic in nature. Within the framework of reflection positive doubles, we give necessary and sufficient conditions for reflection positivity. We use a reflection-invariant cone to implement our construction. Our characterization allows for a direct interpretation in t...

  8. Developing the reflective teacher.

    Science.gov (United States)

    Scanlan, J M; Chernomas, W M

    1997-06-01

    The conceptual issues and research findings surrounding the meaning and use of reflection are examined in this paper and serve as a foundation for discussing significant assumptions and beliefs regarding the use of reflection in nursing education. The strengths and limitations of reflection are discussed. The paper links current knowledge about reflection to the development of reflective thinking and its use by nurse educators and suggests strategies to enhance this development.

  9. Building an international network for a primary care research program: reflections on challenges and solutions in the set-up and delivery of a prospective observational study of acute cough in 13 European countries.

    Science.gov (United States)

    Nuttall, Jacqueline; Hood, Kerenza; Verheij, Theo Jm; Little, Paul; Brugman, Curt; Veen, Robert Er; Goossens, Herman; Butler, Christopher C

    2011-07-27

    Implementing a primary care clinical research study in several countries can make it possible to recruit sufficient patients in a short period of time that allows important clinical questions to be answered. Large multi-country studies in primary care are unusual and are typically associated with challenges requiring innovative solutions. We conducted a multi-country study and through this paper, we share reflections on the challenges we faced and some of the solutions we developed with a special focus on the study set up, structure and development of Primary Care Networks (PCNs). GRACE-01 was a multi-European country, investigator-driven prospective observational study implemented by 14 Primary Care Networks (PCNs) within 13 European Countries. General Practitioners (GPs) recruited consecutive patients with an acute cough. GPs completed a case report form (CRF) and the patient completed a daily symptom diary. After study completion, the coordinating team discussed the phases of the study and identified challenges and solutions that they considered might be interesting and helpful to researchers setting up a comparable study. The main challenges fell within three domains as follows:i) selecting, setting up and maintaining PCNs;ii) designing local context-appropriate data collection tools and efficient data management systems; andiii) gaining commitment and trust from all involved and maintaining enthusiasm.The main solutions for each domain were:i) appointing key individuals (National Network Facilitator and Coordinator) with clearly defined tasks, involving PCNs early in the development of study materials and procedures.ii) rigorous back translations of all study materials and the use of information systems to closely monitor each PCNs progress;iii) providing strong central leadership with high level commitment to the value of the study, frequent multi-method communication, establishing a coherent ethos, celebrating achievements, incorporating social events and

  10. Correlation of ''twins'' observed by optical microscopy and transmission electron microscopy in YBa2Cu3O7/sub -//sub x/ superconductors

    International Nuclear Information System (INIS)

    Hoff, H.A.; Singh, A.K.; Pande, C.S.

    1988-01-01

    By using transmission electron microscopy and optical microscopy on the same specimens, the patterns of light- and dark-contrast lines seen in reflected polarized light were shown to be an interference pattern due to the variable spacing of suboptical microtwins. These microtwins are mostly [110] reflection twins. The [110] twinning was observed to be cyclic and occasionally pseudotetragonal because of the progressive cycling of contact twin domains. Within a domain, and occasionally in a whole grain, the [110] reflection twins occurred as polysynthetic lamellae. The morphology of the domain structure can be explained from the theory of martensitic transformation

  11. Scanning Tunneling Microscopy - image interpretation

    International Nuclear Information System (INIS)

    Maca, F.

    1998-01-01

    The basic ideas of image interpretation in Scanning Tunneling Microscopy are presented using simple quantum-mechanical models and supplied with examples of successful application. The importance is stressed of a correct interpretation of this brilliant experimental surface technique

  12. Diagnosis of Acanthamoeba keratitis in vivo with confocal microscopy.

    Science.gov (United States)

    Winchester, K; Mathers, W D; Sutphin, J E; Daley, T E

    1995-01-01

    We present eight cases of Acanthamoeba keratitis. In each case; the Acanthamoeba organisms were visualized in the epithelium and anterior stroma using tandem scanning confocal microscopy. The organisms were highly reflective, ovoid, and were 10-25 microns in diameter. The Acanthamoeba organisms in the human corneas were identical in size and shape to Acanthamoeba organisms on an agar plate visualized with the same confocal microscope. Confocal microscopy is a useful method for identifying Acanthamoeba organisms in vivo within the corneal epithelium and anterior stroma.

  13. Transmission electron microscopy physics of image formation and microanalysis

    CERN Document Server

    Reimer, Ludwig

    1989-01-01

    The aim of this book is to present the theory of image and contrast formation and the analytical modes in transmission electron microscopy The principles of particle and wave optics of electrons are described Electron-specimen interactions are discussed for evaluating the theory of scattering and phase contrast Also discussed are the kinematical and dynamical theories of electron diffraction and their applications for crystal structure determination and imaging of lattice defects X-ray microanalysis and energy-loss spectroscopy are treated as analytical methods The second edition includes discussion of recent progress, especially in the areas of energy-loss spectroscopy, crystal-lattice imaging and reflection electron microscopy

  14. Electronic microscopy application in artificial minerals

    International Nuclear Information System (INIS)

    Gomez, L E.

    1995-07-01

    One of the uses of electronic microscopy in combination with the analysis microprobe EDAX is to characterize the properties of the minerals. The technique consist of studying the chemical composition by elements or by oxides of particles which can be enlarged successfully up to 100000x. With the help of the optical microscope one is able to determine the textual characteristics, the form, cleavage and other cristallographic properties which, combined with microprobe analysis enable one to determine its classification. The industrial processes which use ovens usually have problems due to the formation of impurities, spots and abnormal aspects which are reflected in a lower quality of the final material produced. These types of defects appear in minerals which are made in laboratories; knowing the natural minerals one can exercise a better quality control since this permits to know the behaviour of the raw material at a particular temperature and its reactions depending on the additives used

  15. Reflection Positivity for Parafermions

    OpenAIRE

    Jaffe, Arthur; Pedrocchi, Fabio L.

    2014-01-01

    We establish reflection positivity for Gibbs trace states for a class of gauge-invariant, reflection-invariant Hamiltonians describing parafermion interactions on a lattice. We relate these results to recent work in the condensed-matter physics literature.

  16. Temperature-reflection I

    DEFF Research Database (Denmark)

    McGady, David A.

    2017-01-01

    that T-reflection is unrelated to time-reversal. Finally, we study the interplay between T-reflection and perturbation theory in the anharmonic harmonic oscillator in quantum mechanics and in Yang-Mills in four-dimensions. This is the first in a series of papers on temperature-reflections.......In this paper, we revisit the claim that many partition functions are invariant under reflecting temperatures to negative values (T-reflection). The goal of this paper is to demarcate which partition functions should be invariant under T-reflection, and why. Our main claim is that finite......-temperature path integrals for quantum field theories (QFTs) should be T-reflection invariant. Because multi-particle partition functions are equal to Euclidean path integrals for QFTs, we expect them to be T-reflection invariant. Single-particle partition functions though are often not invariant under T...

  17. Dissenting in Reflective Conversations

    DEFF Research Database (Denmark)

    Bjørn, Pernille; Boulus, Nina

    2011-01-01

    a methodological reflective approach that provides space for taking seriously uncertainties experienced in the field as these can be a catalyst for learning and sharpening our theoretical and empirical skills as action researchers. Through first-person inquiry, we investigate how our reflective conversations...... gradually evolved into second-person inquiry. We argue that enacting second-person reflective conversations renders alternative strategies for handling uncertainties through articulation of the tacit assumptions within particular empirical situations. Finally, we argue that reflective conversations should...

  18. Capturing the surface texture and shape of pollen: a comparison of microscopy techniques.

    Directory of Open Access Journals (Sweden)

    Mayandi Sivaguru

    Full Text Available Research on the comparative morphology of pollen grains depends crucially on the application of appropriate microscopy techniques. Information on the performance of microscopy techniques can be used to inform that choice. We compared the ability of several microscopy techniques to provide information on the shape and surface texture of three pollen types with differing morphologies. These techniques are: widefield, apotome, confocal and two-photon microscopy (reflected light techniques, and brightfield and differential interference contrast microscopy (DIC (transmitted light techniques. We also provide a first view of pollen using super-resolution microscopy. The three pollen types used to contrast the performance of each technique are: Croton hirtus (Euphorbiaceae, Mabea occidentalis (Euphorbiaceae and Agropyron repens (Poaceae. No single microscopy technique provided an adequate picture of both the shape and surface texture of any of the three pollen types investigated here. The wavelength of incident light, photon-collection ability of the optical technique, signal-to-noise ratio, and the thickness and light absorption characteristics of the exine profoundly affect the recovery of morphological information by a given optical microscopy technique. Reflected light techniques, particularly confocal and two-photon microscopy, best capture pollen shape but provide limited information on very fine surface texture. In contrast, transmitted light techniques, particularly differential interference contrast microscopy, can resolve very fine surface texture but provide limited information on shape. Texture comprising sculptural elements that are spaced near the diffraction limit of light (~250 nm; NDL presents an acute challenge to optical microscopy. Super-resolution structured illumination microscopy provides data on the NDL texture of A. repens that is more comparable to textural data from scanning electron microscopy than any other optical

  19. Liberating Moral Reflection

    Science.gov (United States)

    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…

  20. Reflecting on Masters Dissertations

    Science.gov (United States)

    Duke, Christopher

    2013-01-01

    In this paper I reflect on my own practice as a supervisor of taught postgraduate students. By outlining my own process of reflection I demonstrate that, despite some minor issues, Brew & Peseta's (2004) ten criteria for good supervisory practice of research postgraduates can be used as tool with which to reflect upon and improve one's…

  1. Proximal design for a multimodality endoscope with multiphoton microscopy, optical coherence microscopy and visual modalities

    Science.gov (United States)

    Kiekens, Kelli C.; Talarico, Olivia; Barton, Jennifer K.

    2018-02-01

    A multimodality endoscope system has been designed for early detection of ovarian cancer. Multiple illumination and detection systems must be integrated in a compact, stable, transportable configuration to meet the requirements of a clinical setting. The proximal configuration presented here supports visible light navigation with a large field of view and low resolution, high resolution multiphoton microscopy (MPM), and high resolution optical coherence microscopy (OCM). All modalities are integrated into a single optical system in the endoscope. The system requires two light sources: a green laser for visible light navigation and a compact fiber based femtosecond laser for MPM and OCM. Using an inline wavelength division multiplexer, the two sources are combined into a single mode fiber. To accomplish OCM, a fiber coupler is used to separate the femtosecond laser into a reference arm and signal arm. The reflected reference arm and the signal from the sample are interfered and wavelength separated by a reflection grating and detected using a linear array. The MPM signal is collimated and goes through a series of filters to separate the 2nd and 3rd harmonics as well as twophoton excitation florescence (2PEF) and 3PEF. Each signal is independently detected on a photo multiplier tube and amplified. The visible light is collected by multiple high numerical aperture fibers at the endoscope tip which are bundled into one SMA adapter at the proximal end and connected to a photodetector. This integrated system design is compact, efficient and meets both optical and mechanical requirements for clinical applications.

  2. Quantitative in situ attenuated total internal reflection Fourier transform infrared study of the isotherms of poly(sodium 4-styrene sulfonate) adsorption to a TiO2 surface over a range of cetylpyridinium bromide monohydrate concentration.

    Science.gov (United States)

    Hase, Mike; Scheffelmaier, Ryan; Hayden, Sarah; Rivera, Dion

    2010-04-20

    Quantitative in situ attenuated total internal reflection Fourier transform infrared (ATR FTIR) spectroscopy has been used to study the isotherm of poly(sodium 4-styrene sulfonate), PSS, adsorption to a TiO(2) surface in aqueous solution at a pH of 3.5. The effect of adding surfactant cetylpyridinium bromide monohydrate (CPBM) on the adsorption isotherm of PSS was investigated at CPBM concentrations of 3.60 x 10(-7), 1.02 x 10(-5), and 1.04 x 10(-4) M. The use of in situ ATR FTIR allowed for the calculation of the concentration of both PSS and CPBM at the TiO(2)/water interface over the entire course of all experiments. It was found that the addition of a small amount of CPBM, 3.60 x 10(-7) M, to PSS solutions resulted in 23 +/- 3% less PSS accumulating at the TiO(2)/water interface compared to isotherm studies with no CPBM present. The mole ratio of CPBM to PSS varies from 4 +/- 1 to 1 to 20 +/- 4 to 1 in a stepwise manner as the solution concentration of PSS is increased for solutions with a CPBM concentration of 3.60 x 10(-7). The addition of CPBM at concentrations of 1.02 x 10(-5) and 1.04 x 10(-4) M showed distinct differences in the behavior of the PSS isotherm, but at the highest solution PSS concentrations, the amount of PSS at the TiO(2)/water interface compared to that of PSS solutions with no CPBM added is indistinguishable within the experimental uncertainties. For these higher concentrations of CPBM, both PSS and CPBM appear to come to the TiO(2) surface as aggregates and the mole ratio of CPBM to PSS at the TiO(2)/water interface decreases as the concentration of PSS is increased. For a CPBM concentration of 1.02 x 10(-5) M, the mole ratio of CPBM to PSS changes from 139 +/- 29 to 1 to 33 +/- 7 to 1 as the solution PSS concentration is increased. For a CPBM concentration of 1.04 x 10(-4) M, the mole ratio of CPBM to PSS changes from 630 +/- 130 to 1 to 110 +/- 21 to 1 as the solution PSS concentration is increased. Despite the large differences in the

  3. Light microscopy - Methods and protocols

    Directory of Open Access Journals (Sweden)

    CarloAlberto Redi

    2011-11-01

    Full Text Available The first part of the book (six chapters is devoted to some selected applications of bright-field microscopy while the second part (eight chapters to some fluorescence microscopy studies. Both animal and plant biology investigations are presented covering multiple fields like immunology, cell signaling, cancer biology and, surprisingly to me, ecology. This chapter is titled: Light microscopy in aquatic ecology: Methods for plankton communities studies and it is due to Maria Carolina S. Soares and colleagues from the Laboratory of Aquatic Ecology, Dept. of Biology, Federal University of Juiz de Fora (Brazil. Here they present methods to quantify the different component of planktonic communities in a step-by-step manner so that virus, bacteria, algae and animals pertaining to different taxa can be recognized and the contribution they made to the plankton composition evaluated. It descends that even how the plankton composition is changing due to environmental variations can be accurately determined....

  4. Image scanning microscopy: an overview.

    Science.gov (United States)

    Ward, E N; Pal, R

    2017-05-01

    For almost a century, the resolution of optical microscopy was thought to be limited by Abbé's law describing the diffraction limit of light. At the turn of the millennium, aided by new technologies and fluorophores, the field of optical microscopy finally surpassed the diffraction barrier: a milestone achievement that has been recognized by the 2014 Nobel Prize in Chemistry. Many super-resolution methods rely on the unique photophysical properties of the fluorophores to improve resolution, posing significant limitations on biological imaging, such as multicoloured staining, live-cell imaging and imaging thick specimens. Structured Illumination Microscopy (SIM) is one branch of super-resolution microscopy that requires no such special properties of the applied fluorophores, making it more versatile than other techniques. Since its introduction in biological imaging, SIM has proven to be a popular tool in the biologist's arsenal for following biological interaction and probing structures of nanometre scale. SIM continues to see much advancement in design and implementation, including the development of Image Scanning Microscopy (ISM), which uses patterned excitation via either predefined arrays or raster-scanned single point-spread functions (PSF). This review aims to give a brief overview of the SIM and ISM processes and subsequent developments in the image reconstruction process. Drawing from this, and incorporating more recent achievements in light shaping (i.e. pattern scanning and super-resolution beam shaping), this study also intends to suggest potential future directions for this ever-expanding field. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  5. Nanoscale Laser Terahertz Emission Microscopy

    DEFF Research Database (Denmark)

    Klarskov, Pernille; Kim, Hyewon; Colvin, Vicki L.

    2017-01-01

    Laser terahertz emission microscopy (LTEM) has become a powerful tool for studying ultrafast dynamics and local fields in many different types of materials. This technique, which relies on acceleration of charge carriers in a material upon femtosecond excitation, can provide insight into the phys......Laser terahertz emission microscopy (LTEM) has become a powerful tool for studying ultrafast dynamics and local fields in many different types of materials. This technique, which relies on acceleration of charge carriers in a material upon femtosecond excitation, can provide insight...

  6. Scanning microscopies of superconductors at very low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Crespo, V.; Maldonado, A.; Galvis, J.A.; Kulkarni, P. [Laboratorio de Bajas Temperaturas, Departamento de Fisica de la Materia Condensada, Instituto de Ciencia de Materiales Nicolas Cabrera, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Guillamon, I. [Laboratorio de Bajas Temperaturas, Departamento de Fisica de la Materia Condensada, Instituto de Ciencia de Materiales Nicolas Cabrera, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Rodrigo, J.G. [Laboratorio de Bajas Temperaturas, Departamento de Fisica de la Materia Condensada, Instituto de Ciencia de Materiales Nicolas Cabrera, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Suderow, H., E-mail: hermann.suderow@uam.es [Laboratorio de Bajas Temperaturas, Departamento de Fisica de la Materia Condensada, Instituto de Ciencia de Materiales Nicolas Cabrera, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Vieira, S. [Laboratorio de Bajas Temperaturas, Departamento de Fisica de la Materia Condensada, Instituto de Ciencia de Materiales Nicolas Cabrera, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Banerjee, S. [Department of Physics, Indian Institute of Technology, Kanpur 208 016, UP (India); Rodiere, P. [Institut Neel, CNRS/UJF, 25 Avenue des Martyrs, B.P. 166, 38042 Grenoble Cedex 9 (France)

    2012-09-15

    We discuss basics of Scanning Tunneling Microscopy and Spectroscopy (STM/S) of the superconducting state with normal and superconducting tips. We present a new method to measure the local variations in the Andreev reflection amplitude between a superconducting tip and the sample. This method is termed Scanning Andreev Reflection Spectroscopy (SAS). We also briefly discuss vortex imaging with STM/S under an applied current through the sample, and show the vortex lattice as a function of the angle between the magnetic field and sample's surface.

  7. Scanning microscopies of superconductors at very low temperatures

    International Nuclear Information System (INIS)

    Crespo, V.; Maldonado, A.; Galvis, J.A.; Kulkarni, P.; Guillamon, I.; Rodrigo, J.G.; Suderow, H.; Vieira, S.; Banerjee, S.; Rodiere, P.

    2012-01-01

    We discuss basics of Scanning Tunneling Microscopy and Spectroscopy (STM/S) of the superconducting state with normal and superconducting tips. We present a new method to measure the local variations in the Andreev reflection amplitude between a superconducting tip and the sample. This method is termed Scanning Andreev Reflection Spectroscopy (SAS). We also briefly discuss vortex imaging with STM/S under an applied current through the sample, and show the vortex lattice as a function of the angle between the magnetic field and sample’s surface.

  8. Models og International Entrepreneurship

    DEFF Research Database (Denmark)

    Rask, Morten; Servais, Per

    2015-01-01

    The purpose with this article is to review models used to describe and explain the establishment and development of international new ventures in order to investigate how and why international new ventures are established and developed. This article attempts an integration of extant theory...... on International Entrepreneurship, and specifically but not exclusively, International New Ventures (INVs). The three resulting ‘meta-models’ depict the activities and loci of such firms, the motivating factors that give rise to such firms and their growth modalities and strategies. These models reflect the merger...... of entrepreneurship and international business into the field of international entrepreneurship....

  9. Reflection group on 'Expert Culture'

    International Nuclear Information System (INIS)

    Eggermont, G.

    2000-01-01

    As part of SCK-CEN's social sciences and humanities programme, a reflection group on 'Expert Culture' was established. The objectives of the reflection group are: (1) to clarify the role of SCK-CEN experts; (2) to clarify the new role of expertise in the evolving context of risk society; (3) to confront external views and internal SCK-CEN experiences on expert culture; (4) to improve trust building of experts and credibility of SCK-CEN as a nuclear actor in society; (5) to develop a draft for a deontological code; (6) to integrate the approach in training on assertivity and communication; (7) to create an output for a topical day on the subject of expert culture. The programme, achievements and perspectives of the refection group are summarised

  10. Four-dimensional electron microscopy.

    Science.gov (United States)

    Zewail, Ahmed H

    2010-04-09

    The discovery of the electron over a century ago and the realization of its dual character have given birth to one of the two most powerful imaging instruments: the electron microscope. The electron microscope's ability to resolve three-dimensional (3D) structures on the atomic scale is continuing to affect different fields, including materials science and biology. In this Review, we highlight recent developments and inventions made by introducing the fourth dimension of time in electron microscopy. Today, ultrafast electron microscopy (4D UEM) enables a resolution that is 10 orders of magnitude better than that of conventional microscopes, which are limited by the video-camera rate of recording. After presenting the central concept involved, that of single-electron stroboscopic imaging, we discuss prototypical applications, which include the visualization of complex structures when unfolding on different length and time scales. The developed UEM variant techniques are several, and here we illucidate convergent-beam and near-field imaging, as well as tomography and scanning-pulse microscopy. We conclude with current explorations in imaging of nanomaterials and biostructures and an outlook on possible future directions in space-time, 4D electron microscopy.

  11. Light Microscopy at Maximal Precision

    Science.gov (United States)

    Bierbaum, Matthew; Leahy, Brian D.; Alemi, Alexander A.; Cohen, Itai; Sethna, James P.

    2017-10-01

    Microscopy is the workhorse of the physical and life sciences, producing crisp images of everything from atoms to cells well beyond the capabilities of the human eye. However, the analysis of these images is frequently little more accurate than manual marking. Here, we revolutionize the analysis of microscopy images, extracting all the useful information theoretically contained in a complex microscope image. Using a generic, methodological approach, we extract the information by fitting experimental images with a detailed optical model of the microscope, a method we call parameter extraction from reconstructing images (PERI). As a proof of principle, we demonstrate this approach with a confocal image of colloidal spheres, improving measurements of particle positions and radii by 10-100 times over current methods and attaining the maximum possible accuracy. With this unprecedented accuracy, we measure nanometer-scale colloidal interactions in dense suspensions solely with light microscopy, a previously impossible feat. Our approach is generic and applicable to imaging methods from brightfield to electron microscopy, where we expect accuracies of 1 nm and 0.1 pm, respectively.

  12. Quantitative super-resolution microscopy

    NARCIS (Netherlands)

    Harkes, Rolf

    2016-01-01

    Super-Resolution Microscopy is an optical fluorescence technique. In this thesis we focus on single molecule super-resolution, where the position of single molecules is determined. Typically these molecules can be localized with a 10 to 30nm precision. This technique is applied in four different

  13. Four-Dimensional Electron Microscopy

    Science.gov (United States)

    Zewail, Ahmed H.

    2010-04-01

    The discovery of the electron over a century ago and the realization of its dual character have given birth to one of the two most powerful imaging instruments: the electron microscope. The electron microscope’s ability to resolve three-dimensional (3D) structures on the atomic scale is continuing to affect different fields, including materials science and biology. In this Review, we highlight recent developments and inventions made by introducing the fourth dimension of time in electron microscopy. Today, ultrafast electron microscopy (4D UEM) enables a resolution that is 10 orders of magnitude better than that of conventional microscopes, which are limited by the video-camera rate of recording. After presenting the central concept involved, that of single-electron stroboscopic imaging, we discuss prototypical applications, which include the visualization of complex structures when unfolding on different length and time scales. The developed UEM variant techniques are several, and here we illucidate convergent-beam and near-field imaging, as well as tomography and scanning-pulse microscopy. We conclude with current explorations in imaging of nanomaterials and biostructures and an outlook on possible future directions in space-time, 4D electron microscopy.

  14. Near-field Optical Microscopy

    NARCIS (Netherlands)

    Ruiter, A.G.T.

    1997-01-01

    Near-field scanning optical microscopy (NSOM) is one of the most recent scanning probe techniques. In this technique, an optical probe is brought in the vicinity of the sample surface, in the near-field zone. The microscope can either work in illumination mode, in which the probe consists of a

  15. Mechanics in Steels through Microscopy

    NARCIS (Netherlands)

    Tirumalasetty, G.K.

    2013-01-01

    The goal of the study consolidated in this thesis is to understand the mechanics in steels using microscopy. In particular, the mechanical response of Transformation Induced Plasticity (TRIP) steels is correlated with their microstructures. Chapter 1 introduces the current state of the art of TRIP

  16. High Resolution Scanning Ion Microscopy

    NARCIS (Netherlands)

    Castaldo, V.

    2011-01-01

    The structure of the thesis is the following. The first chapter is an introduction to scanning microscopy, where the path that led to the Focused Ion Beam (FIB) is described and the main differences between electrons and ion beams are highlighted. Chapter 2 is what is normally referred to (which I

  17. Filter-Dense Multicolor Microscopy.

    Directory of Open Access Journals (Sweden)

    Siavash Kijani

    Full Text Available Immunofluorescence microscopy is a unique method to reveal the spatial location of proteins in tissues and cells. By combining antibodies that are labeled with different fluorochromes, the location of several proteins can simultaneously be visualized in one sample. However, because of the risk of bleed-through signals between fluorochromes, standard multicolor microscopy is restricted to a maximum of four fluorescence channels, including one for nuclei staining. This is not always enough to address common scientific questions. In particular, the use of a rapidly increasing number of marker proteins to classify functionally distinct cell populations and diseased tissues emphasizes the need for more complex multistainings. Hence, multicolor microscopy should ideally offer more channels to meet the current needs in biomedical science. Here we present an enhanced multi-fluorescence setup, which we call Filter-Dense Multicolor Microscopy (FDMM. FDMM is based on condensed filter sets that are more specific for each fluorochrome and allow a more economic use of the light spectrum. FDMM allows at least six independent fluorescence channels and can be applied to any standard fluorescence microscope without changing any operative procedures for the user. In the present study, we demonstrate an FDMM setup of six channels that includes the most commonly used fluorochromes for histology. We show that the FDMM setup is specific and robust, and we apply the technique on typical biological questions that require more than four fluorescence microscope channels.

  18. Illuminating Electron Microscopy of Photocatalysts

    DEFF Research Database (Denmark)

    Cavalca, Filippo

    Photocatalysts are of fundamental interest for sustainable energy research [1]. By means of transmission electron microscopy (TEM) it is possible to obtain deep insight in the structure, composition and reactivity of photocatalysts for their further optimization [2]. We have constructed a novel...

  19. Stochastic Optical Reconstruction Microscopy (STORM).

    Science.gov (United States)

    Xu, Jianquan; Ma, Hongqiang; Liu, Yang

    2017-07-05

    Super-resolution (SR) fluorescence microscopy, a class of optical microscopy techniques at a spatial resolution below the diffraction limit, has revolutionized the way we study biology, as recognized by the Nobel Prize in Chemistry in 2014. Stochastic optical reconstruction microscopy (STORM), a widely used SR technique, is based on the principle of single molecule localization. STORM routinely achieves a spatial resolution of 20 to 30 nm, a ten-fold improvement compared to conventional optical microscopy. Among all SR techniques, STORM offers a high spatial resolution with simple optical instrumentation and standard organic fluorescent dyes, but it is also prone to image artifacts and degraded image resolution due to improper sample preparation or imaging conditions. It requires careful optimization of all three aspects-sample preparation, image acquisition, and image reconstruction-to ensure a high-quality STORM image, which will be extensively discussed in this unit. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  20. 3D -Ray Diffraction Microscopy

    DEFF Research Database (Denmark)

    Poulsen, Henning Friis; Schmidt, Søren; Juul Jensen, Dorte

    2014-01-01

    Three-dimensional X-ray diffraction (3DXRD) microscopy is a fast and non-destructive structural characterization technique aimed at the study of individual crystalline elements (grains or subgrains) within mm-sized polycrystalline specimens. It is based on two principles: the use of highly...

  1. Vacuum scanning capillary photoemission microscopy

    DEFF Research Database (Denmark)

    Aseyev, S.A.; Cherkun, A P; Mironov, B N

    2017-01-01

    We demonstrate the use of a conical capillary in a scanning probe microscopy for surface analysis. The probe can measure photoemission from a substrate by transmitting photoelectrons along the capillary as a function of probe position. The technique is demonstrated on a model substrate consisting...

  2. Advanced Microscopy of Microbial Cells

    DEFF Research Database (Denmark)

    Haagensen, Janus Anders Juul; Regenberg, Birgitte; Sternberg, Claus

    2011-01-01

    Growing awareness of heterogeneity in cells of microbial populations has emphasized the importance of advanced microscopy for visualization and understanding of the molecular mechanisms underlying cell-to-cell variation. In this review, we highlight some of the recent advances in confocal...... for visualization of variation between cells in phenotypic traits such as gene expression....

  3. PHYSICS OF MICROWAVES IN MICROSCOPY

    NARCIS (Netherlands)

    KOK, LP

    1990-01-01

    Microwave technology can help in the preparation of samples for microscopy in many different ways. This paper discusses the physics of microwaves. It gives the theoretical background to understand the practical procedures. Some peculiarities in the optics of microwaves are pointed out. Diffusion

  4. Transmission electron microscopy of bone

    NARCIS (Netherlands)

    Everts, Vincent; Niehof, Anneke; Tigchelaar-Gutter, Wikky; Beertsen, Wouter

    2012-01-01

    This chapter describes procedures to process mineralized tissues obtained from different sources for transmission electron microscopy (TEM). Methods for fixation, resin embedding, staining of semi-thin sections and ultrathin sections are presented. In addition, attention will be paid to processing

  5. Reflective Writing through the Use of Guiding Questions

    Science.gov (United States)

    Moussa-Inaty, Jase

    2015-01-01

    Reflections can be seen as powerful tools for growth and intellectual development. It is no surprise that the writing of reflections is common practice at a Federal Institute in the United Arab Emirates (UAE). The research presented sought to explore possible differences in reflective writing once guidelines were presented to a group of interns in…

  6. ICRP 2015. International symposium on the radiation protection system. Report and reflection on a significant symposium; ICRP 2015. 3. Internationales Symposium zum System des Strahlenschutzes. Bericht und Reflexion ueber ein bedeutsames Symposium

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Bernd

    2016-08-01

    The ICRP international symposium on the radiation protection system provides always extensive information on new developments in radiation protection. The ICRP 2105 discussed the following issues: radiation effects of low dose irradiation, dose coefficients for internal and external exposures, radiation protection in nuclear medicine, application of ICRP recommendations, environmental protection, studies on existing exposure situations, medical radiation protection today, science behind radiation doses, new developments in radiation effects, and ethics in radiation protection.

  7. Microscopy and the helminth parasite.

    Science.gov (United States)

    Halton, David W

    2004-01-01

    Microscopy has a long and distinguished history in the study of helminth parasites and has made a singularly outstanding contribution to understanding how these complex animals organise their lives and relate to their hosts. Increasingly, the microscope has been used as a powerful investigative tool in multidisciplinary approaches to parasitological problems, placing emphasis on functional correlates rather than anatomical detail. In doing so, microscopy has also uncovered a number of attributes of parasites that are of wider significance in the field of biology. Parasite surfaces have understandably demanded most of the attention of microscopists, largely as a result of the pioneering studies using transmission electron microscopy. Their findings focused the attention of physiologists and immunologists on the tegument and cuticle of helminths and in doing so helped unravel the complex molecular exchanges that are fundamental to understanding host-parasite interactions. Scanning electron microscopy succeeded in augmenting these data by revealing novel microtopographical features of the host-parasite relationship, as well as proving invaluable in helminth taxonomy and in assessing the efficacy of test substances in drug screens. Control of helminth parasites has never been more critical: problems of drug resistance demand urgent action to identify exploitable targets for new generation anthelmintics. In this regard, the neuropeptide signalling system of helminths is envisioned as central to nerve-muscle function, and thereby a crucial regulatory influence on their motility, alimentation and reproduction. The use of immunocytochemistry interfaced with confocal scanning laser microscopy has not only been instrumental in discovering the peptidergic system of helminths and its potential for chemotherapeutic exploitation, but through increasingly sophisticated bio-imaging technologies has continued to help dissect and analyse the molecular dynamics of this and other

  8. Self-Reflection

    DEFF Research Database (Denmark)

    Fausing, Bent

    2016-01-01

    and physical bodies are constantly broken with technology. Perception and reflection are in synergy. Reflection means etymologically to bend back, to mirror, and to think. My presentation will take its point of departure in this etymology and make perspectives to modern use of refection in digital media. I......Human experience is based on everything that surrounds us. Not the physical reality, but our perception of and reflection on it. This perception and reflection - presence, intimacy and materiality - are transformed by telematics: Separate rooms can be merged, and the boundaries between our virtual...... will take a look at the establishing of the modern self and possibilities of self-reflection, too. My examples will be from the so-called dark-selfies and from a new selfie form, which merge the present with the previous progressing into the future. I will discuss the media reflections as loos and/or gain...

  9. Self-Reflection

    DEFF Research Database (Denmark)

    Fausing, Bent

    2016-01-01

    Human experience is based on everything that surrounds us. Not the physical reality, but our perception of and reflection on it. This perception and reflection - presence, intimacy and materiality - are transformed by telematics: Separate rooms can be merged, and the boundaries between our virtua....... As another but short viewpoint telepresence, Skype, will be discussed, where new screen types, presence and reflections are established. In a perspective, I debate my term sore-society in relation to my topic and especially the dark selfies....

  10. Interferometric Synthetic Aperture Microscopy: Computed Imaging for Scanned Coherent Microscopy

    Directory of Open Access Journals (Sweden)

    Stephen A. Boppart

    2008-06-01

    Full Text Available Three-dimensional image formation in microscopy is greatly enhanced by the use of computed imaging techniques. In particular, Interferometric Synthetic Aperture Microscopy (ISAM allows the removal of out-of-focus blur in broadband, coherent microscopy. Earlier methods, such as optical coherence tomography (OCT, utilize interferometric ranging, but do not apply computed imaging methods and therefore must scan the focal depth to acquire extended volumetric images. ISAM removes the need to scan the focus by allowing volumetric image reconstruction from data collected at a single focal depth. ISAM signal processing techniques are similar to the Fourier migration methods of seismology and the Fourier reconstruction methods of Synthetic Aperture Radar (SAR. In this article ISAM is described and the close ties between ISAM and SAR are explored. ISAM and a simple strip-map SAR system are placed in a common mathematical framework and compared to OCT and radar respectively. This article is intended to serve as a review of ISAM, and will be especially useful to readers with a background in SAR.

  11. Reflective masks for extreme ultraviolet lithography

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Khanh Bao [Univ. of California, Berkeley, CA (United States)

    1994-05-01

    Extreme ultraviolet lithographic masks are made by patterning multilayer reflective coatings with high normal incidence reflectivity. Masks can be patterned by depositing a patterned absorber layer above the coating or by etching the pattern directly into the coating itself. Electromagnetic simulations showed that absorber-overlayer masks have superior imaging characteristics over etched masks (less sensitive to incident angles and pattern profiles). In an EUVL absorber overlayer mask, defects can occur in the mask substrate, reflective coating, and absorber pattern. Electromagnetic simulations showed that substrate defects cause the most severe image degradation. A printability study of substrate defects for absorber overlayer masks showed that printability of 25 nm high substrate defects are comparable to defects in optical lithography. Simulations also indicated that the manner in which the defects are covered by multilayer reflective coatings can affect printability. Coverage profiles that result in large lateral spreading of defect geometries amplify the printability of the defects by increasing their effective sizes. Coverage profiles of Mo/Si coatings deposited above defects were studied by atomic force microscopy and TEM. Results showed that lateral spread of defect geometry is proportional to height. Undercut at defect also increases the lateral spread. Reductions in defect heights were observed for 0.15 μm wide defect lines. A long-term study of Mo/Si coating reflectivity revealed that Mo/Si coatings with Mo as the top layer suffer significant reductions in reflectivity over time due to oxidation.

  12. Global Explorers Journaling and Reflection Initiative

    Directory of Open Access Journals (Sweden)

    John Bennion

    2016-12-01

    Full Text Available Research suggests that journaling will increase reflection and improve program outcomes (Bain, et al, 1999; Duerden, et al, 2012 This study involved a partnership with a non-profit, Global Explorers (GEx, which provides international immersion experiences for youth. Their programs are designed to teach youth participants principles of leadership, environmental awareness, service, and science. This study, which tested whether teaching journaling techniques to youth program facilitators would have a positive impact on participant outcomes, addressed the following hypotheses: 1 Greater training in reflective thinking among participants would be associated with higher outcome scores, and 2 Participants in the intervention group (facilitators trained in journaling pedagogy would show greater increases in reflective thinking than comparison group members. Results based on participant self-assessment were significant in testing the first hypothesis; reflective thinking is positively associated with outcome measures, but the intervention group did not show increases in reflective thinking.

  13. Characterization of gold nanoparticle films: Rutherford backscattering spectroscopy, scanning electron microscopy with image analysis, and atomic force microscopy

    Directory of Open Access Journals (Sweden)

    Pia C. Lansåker

    2014-10-01

    Full Text Available Gold nanoparticle films are of interest in several branches of science and technology, and accurate sample characterization is needed but technically demanding. We prepared such films by DC magnetron sputtering and recorded their mass thickness by Rutherford backscattering spectroscopy. The geometric thickness dg—from the substrate to the tops of the nanoparticles—was obtained by scanning electron microscopy (SEM combined with image analysis as well as by atomic force microscopy (AFM. The various techniques yielded an internally consistent characterization of the films. In particular, very similar results for dg were obtained by SEM with image analysis and by AFM.

  14. Reflection Positivity and Monotonicity

    OpenAIRE

    Ritter, Gordon; Jaffe, Arthur Michael

    2008-01-01

    We prove general reflection positivity results for both scalar fields and Dirac fields on a Riemannian manifold, and comment on applications to quantum field theory. As another application, we prove the inequality \\(C_D \\leq C_N\\) between Dirichlet and Neumann covariance operators on a manifold with a reflection.

  15. Media for Reflection

    DEFF Research Database (Denmark)

    Knudsen, Morten

    2016-01-01

    This article develops the concept media for reflection in the interest of conceptualizing the interpretative frames that enable and limit reflection in management and leadership education. The concept ‘media for reflection’ allows us to conceptualize the social and cultural mediation of reflectio...

  16. Models of international entrepreneurship

    DEFF Research Database (Denmark)

    Rask, Morten; Servais, Per

    2012-01-01

    The purpose with this article is to review models used to describe and explain the establishment and development of international new ventures in order to investigate how and why international new ventures are established and developed. This article attempts an integration of extant theory...... on International Entrepreneurship, and specifically but not exclusively, International New Ventures (INVs). The three resulting ‘meta-models’ depict the activities and loci of such firms (Figure 1), the motivating factors that give rise to such firms (Figure 2) and their growth modalities and strategies (Figure 3......). These models reflect the merger of entrepreneurship and international business into the field of international entrepreneurship. Managers in international entrepreneurial firms and students in international business and entrepreneurship can use the models as framework for understanding international...

  17. Selective sensitivity in Kerr microscopy

    Science.gov (United States)

    Soldatov, I. V.; Schäfer, R.

    2017-07-01

    A new technique for contrast separation in wide-field magneto-optical Kerr microscopy is introduced. Utilizing the light from eight light emitting diodes, guided to the microscope by glass fibers and being switched synchronously with the camera exposure, domain images with orthogonal in-plane sensitivity can be displayed simultaneously at real-time, and images with pure in-plane or polar contrast can be obtained. The benefit of this new method of contrast separation is demonstrated for Permalloy films, a NdFeB sinter magnet, and a cobalt crystal. Moreover, the new technique is shown to strongly enhance the sensitivity of Kerr microscopy by eliminating parasitic contrast contributions occurring in conventional setups. A doubling of the in-plane domain contrast and a sensitivity to Kerr rotations as low as 0.6 mdeg is demonstrated.

  18. All-optical photoacoustic microscopy

    Directory of Open Access Journals (Sweden)

    Sung-Liang Chen

    2015-12-01

    Full Text Available Three-dimensional photoacoustic microscopy (PAM has gained considerable attention within the biomedical imaging community during the past decade. Detecting laser-induced photoacoustic waves by optical sensing techniques facilitates the idea of all-optical PAM (AOPAM, which is of particular interest as it provides unique advantages for achieving high spatial resolution using miniaturized embodiments of the imaging system. The review presents the technology aspects of optical-sensing techniques for ultrasound detection, such as those based on optical resonators, as well as system developments of all-optical photoacoustic systems including PAM, photoacoustic endoscopy, and multi-modality microscopy. The progress of different AOPAM systems and their representative applications are summarized.

  19. High-resolution electron microscopy

    CERN Document Server

    Spence, John C H

    2013-01-01

    This new fourth edition of the standard text on atomic-resolution transmission electron microscopy (TEM) retains previous material on the fundamentals of electron optics and aberration correction, linear imaging theory (including wave aberrations to fifth order) with partial coherence, and multiple-scattering theory. Also preserved are updated earlier sections on practical methods, with detailed step-by-step accounts of the procedures needed to obtain the highest quality images of atoms and molecules using a modern TEM or STEM electron microscope. Applications sections have been updated - these include the semiconductor industry, superconductor research, solid state chemistry and nanoscience, and metallurgy, mineralogy, condensed matter physics, materials science and material on cryo-electron microscopy for structural biology. New or expanded sections have been added on electron holography, aberration correction, field-emission guns, imaging filters, super-resolution methods, Ptychography, Ronchigrams, tomogr...

  20. Contact microscopy with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Panessa-Warren, B.J.

    1985-10-01

    Soft x-ray contact microscopy with synchrotron radiation offers the biologist and especially the microscopist, a way to morphologically study specimens that could not be imaged by conventional TEM, STEM or SEM methods (i.e. hydrated samples, samples easily damaged by an electron beam, electron dense samples, thick specimens, unstained low contrast specimens) at spatial resolutions approaching those of the TEM, with the additional possibility to obtain compositional (elemental) information about the sample as well. Although flash x-ray sources offer faster exposure times, synchrotron radiation provides a highly collimated, intense radiation that can be tuned to select specific discrete ranges of x-ray wavelengths or specific individual wavelengths which optimize imaging or microanalysis of a specific sample. This paper presents an overview of the applications of x-ray contact microscopy to biological research and some current research results using monochromatic synchrotron radiation to image biological samples. 24 refs., 10 figs.

  1. QUANTITATIVE CONFOCAL LASER SCANNING MICROSCOPY

    Directory of Open Access Journals (Sweden)

    Merete Krog Raarup

    2011-05-01

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

  2. Selective sensitivity in Kerr microscopy.

    Science.gov (United States)

    Soldatov, I V; Schäfer, R

    2017-07-01

    A new technique for contrast separation in wide-field magneto-optical Kerr microscopy is introduced. Utilizing the light from eight light emitting diodes, guided to the microscope by glass fibers and being switched synchronously with the camera exposure, domain images with orthogonal in-plane sensitivity can be displayed simultaneously at real-time, and images with pure in-plane or polar contrast can be obtained. The benefit of this new method of contrast separation is demonstrated for Permalloy films, a NdFeB sinter magnet, and a cobalt crystal. Moreover, the new technique is shown to strongly enhance the sensitivity of Kerr microscopy by eliminating parasitic contrast contributions occurring in conventional setups. A doubling of the in-plane domain contrast and a sensitivity to Kerr rotations as low as 0.6 mdeg is demonstrated.

  3. Illuminating Electron Microscopy of Photocatalysts

    DEFF Research Database (Denmark)

    Cavalca, Filippo

    Photocatalysts are of fundamental interest for sustainable energy research because of their wide range of applications and great potential for state of the art and future usages [1]. By means of Transmission Electron Microscopy (TEM) it is possible to give a deep insight in the structure, composi......Photocatalysts are of fundamental interest for sustainable energy research because of their wide range of applications and great potential for state of the art and future usages [1]. By means of Transmission Electron Microscopy (TEM) it is possible to give a deep insight in the structure....... The holder is implemented with a laser diode and an optical system that guides the light onto the sample surface with maximum power transmission. The source can be changed and tuned according to the needs, in principle spanning the whole visible and UV light spectrum. It is possible to use the device inside...

  4. Multifunctional scanning ion conductance microscopy

    OpenAIRE

    Page, Ashley; Perry, David; Unwin, Patrick R.

    2017-01-01

    Scanning ion conductance microscopy (SICM) is a nanopipette-based technique that has traditionally been used to image topography or to deliver species to an interface, particularly in a biological setting. This article highlights the recent blossoming of SICM into a technique with a much greater diversity of applications and capability that can be used either standalone, with advanced control (potential–time) functions, or in tandem with other methods. SICM can be used to elucidate functional...

  5. CNNs for electron microscopy segmentation

    OpenAIRE

    García-Amorena García, Pablo

    2013-01-01

    In the framework of Biomedicine, mitochondria are known to play an important role in neural function. Recent studies show mitochondrial morphology to be crucial to cellular physiology and synaptic function, and a link between mitochondrial defects and neuro-degenerative diseases is strongly suspected. Electron microscopy (EM), with its very high resolution in all three directions, is one of the key tools to look more closely into these tissues, but the huge amounts of data it produces m...

  6. Paleomagnetic Analysis Using SQUID Microscopy

    Science.gov (United States)

    Weiss, Benjamin P.; Lima, Eduardo A.; Fong, Luis E.; Baudenbacher, Franz J.

    2007-01-01

    Superconducting quantum interference device (SQUID) microscopes are a new generation of instruments that map magnetic fields with unprecedented spatial resolution and moment sensitivity. Unlike standard rock magnetometers, SQUID microscopes map magnetic fields rather than measuring magnetic moments such that the sample magnetization pattern must be retrieved from source model fits to the measured field data. In this paper, we presented the first direct comparison between paleomagnetic analyses on natural samples using joint measurements from SQUID microscopy and moment magnetometry. We demonstrated that in combination with apriori geologic and petrographic data, SQUID microscopy can accurately characterize the magnetization of lunar glass spherules and Hawaiian basalt. The bulk moment magnitude and direction of these samples inferred from inversions of SQUID microscopy data match direct measurements on the same samples using moment magnetometry. In addition, these inversions provide unique constraints on the magnetization distribution within the sample. These measurements are among the most sensitive and highest resolution quantitative paleomagnetic studies of natural remanent magnetization to date. We expect that this technique will be able to extend many other standard paleomagnetic techniques to previously inaccessible microscale samples.

  7. Multi-photon excitation microscopy

    Directory of Open Access Journals (Sweden)

    Faretta Mario

    2006-06-01

    Full Text Available Abstract Multi-photon excitation (MPE microscopy plays a growing role among microscopical techniques utilized for studying biological matter. In conjunction with confocal microscopy it can be considered the imaging workhorse of life science laboratories. Its roots can be found in a fundamental work written by Maria Goeppert Mayer more than 70 years ago. Nowadays, 2PE and MPE microscopes are expected to increase their impact in areas such biotechnology, neurobiology, embryology, tissue engineering, materials science where imaging can be coupled to the possibility of using the microscopes in an active way, too. As well, 2PE implementations in noninvasive optical bioscopy or laser-based treatments point out to the relevance in clinical applications. Here we report about some basic aspects related to the phenomenon, implications in three-dimensional imaging microscopy, practical aspects related to design and realization of MPE microscopes, and we only give a list of potential applications and variations on the theme in order to offer a starting point for advancing new applications and developments.

  8. Comparative study of electron microscopy and scanning probe microscopy in photosynthetic research

    OpenAIRE

    MATĚNOVÁ, Martina

    2009-01-01

    The aim of this study is to compare the ability of transmission electron microscopy, scanning electron microscopy and atomic force microscopy to visualize individual protein complexes. The principle of electron microscopy and atomic force microscopy is explained. For comparision of these methods well characterized photosynthetic complexes LH1, LH2, PSI and PSII were selected.

  9. Small-scale Farmer Access to International Agri-Food Chains : a BOP-Based Reflection on the Need for Socially Embedded Innovation in the Coffee and Flower Sector

    NARCIS (Netherlands)

    Danse, M.G.; Vellema, S.

    2007-01-01

    Internationalisation of agro-food chains offers agricultural sectors in developing economies prospects in profitable and competitive international markets. Market access strategies often seem to assume poverty alleviation as one of the outcomes. This paper aims to be more precise about the required

  10. Ex vivo laser confocal microscopy findings of cultured Acanthamoeba trophozoites

    Directory of Open Access Journals (Sweden)

    Yamazaki N

    2012-08-01

    Full Text Available Natsuko Yamazaki,1 Akira Kobayashi,1 Hideaki Yokogawa,1 Yasuhisa Ishibashi,2 Yosaburo Oikawa,3 Masaharu Tokoro,4 Kazuhisa Sugiyama11Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan; 2Department of Ophthalmology, East Washinomiya Hospital, Kuki, Japan; 3Department of Medical Zoology, Kanazawa Medical University, Kahoku, Japan; 4Department of Parasitology, Kanazawa University Graduate School of Medical Science, Kanazawa, JapanPurpose: The purpose of the current study was to investigate ex vivo laser confocal microscopic findings of cultured Acanthamoeba trophozoites obtained from Acanthamoeba keratitis patients.Methods: Eight cultured samples of Acanthamoeba trophozoites from eight eyes of seven patients (mean age, 26.9 years; age range, 18–52 years were used. Seven samples were from corneal scrapings of Acanthamoeba keratitis patients and one sample was from the solution in a soft contact lens case. Ex vivo laser confocal microscopy was performed to qualitatively evaluate the shape and degree of light reflection of the living Acanthamoeba trophozoites.Results: Ex vivo laser confocal microscopy demonstrated highly reflective, high-contrast Acanthamoeba trophozoites with no walls (mean size, 25.4 µm; range, 17.1–58.5 µm. The shapes of the trophozoites were highly pleomorphic, and some showed characteristic acanthopodia by laser confocal microscopy.Conclusion: Ex vivo laser confocal microscopy was effective in demonstrating cultured Acanthamoeba trophozoites of various shapes and sizes. The observations of the current study may be helpful when similar structures are identified under in vivo conditions.Keywords: Acanthamoeba, trophozoite, laser confocal microscopy

  11. Storage array reflection considerations

    International Nuclear Information System (INIS)

    Haire, M.J.; Jordan, W.C.; Taylor, R.G.

    1997-01-01

    The assumptions used for reflection conditions of single containers are fairly well established and consistently applied throughout the industry in nuclear criticality safety evaluations. Containers are usually considered to be either fully water reflected (i.e., surrounded by 6 to 12 in. of water) for safety calculations or reflected by 1 in. of water for nominal (structural material and air) conditions. Tables and figures are usually available for performing comparative evaluations of containers under various loading conditions. Reflection considerations used for evaluating the safety of storage arrays of fissile material are not as well established. When evaluating arrays, it has become more common for analysts to use calculations to demonstrate the safety of the array configuration. In performing these calculations, the analyst has considerable freedom concerning the assumptions made for modeling the reflection of the array. Considerations are given for the physical layout of the array with little or no discussion (or demonstration) of what conditions are bounded by the assumed reflection conditions. For example, an array may be generically evaluated by placing it in a corner of a room in which the opposing walls are far away. Typically, it is believed that complete flooding of the room is incredible, so the array is evaluated for various levels of water mist interspersed among array containers. This paper discusses some assumptions that are made regarding storage array reflection

  12. French Society of Microscopy, 10. conference

    International Nuclear Information System (INIS)

    Thibault-Penisson, J.; Cremer, Ch.; Susini, J.; Kirklanda, A.I.; Rigneault, H.; Renault, O.; Bailly, A.; Zagonel, L.F.; Barrett, N.; Bogner, A.; Gauthier, C.; Jouneau, P.H.; Thollet, G.; Fuchs, G.; Basset, D.; Deconihout, B.; Vurpillot, F.; Vella, A.; Matthieu, G.; Cadel, E.; Bostel, A.; Blavette, D.; Baumeister, W.; Usson, Y.; Zaefferer, St.; Laffont, L.; Weyland, M.; Thomas, J.M.; Midgley, P.; Benlekbir, S.; Epicier, Th.; Diop, B.N.; Roux, St.; Ou, M.; Perriat, P.; Bausach, M.; Aouine, M.; Berhault, G.; Idrissi, H.; Cottevieille, M.; Jonic, S.; Larquet, E.; Svergun, D.; Vannoni, M.A.; Boisset, N.; Ersena, O.; Werckmann, J.; Ulhaq, C.; Hirlimann, Ch.; Tihay, F.; Cuong, Pham-Huu; Crucifix, C.; Schultz, P.; Jornsanoha, P.; Thollet, G.; Masenelli-Varlot, K.; Gauthier, C.; Ludwig, W.; King, A.; Johnson, G.; Gonzalves-Hoennicke, M.; Reischig, P.; Messaoudi, C.; Ibrahim, R.; Marco, S.; Klie, R.F.; Zhao, Y.; Yang, G.; Zhu, Y.; Hue, F.; Hytch, M.; Hartmann, J.M.; Bogumilowicz, Y.; Claverie, A.; Klein, H.; Alloyeau, D.; Ricolleau, C.; Langlois, C.; Le Bouar, Y.; Loiseau, A.; Colliex, C.; Stephan, O.; Kociak, M.; Tence, M.; Gloter, A.; Imhoff, D.; Walls, M.; Nelayah, J.; March, K.; Couillard, M.; Ailliot, C.; Bertin, F.; Cooper, D.; Rivallin, P.; Dumelie, N.; Benhayoune, H.; Balossier, G.; Cheynet, M.; Pokrant, S.; Tichelaar, F.; Rouviere, J.L.; Cooper, D.; Truche, R.; Chabli, A.; Debili, M.Y.; Houdellier, F.; Warot-Fonrose, B.; Hytch, M.J.; Snoeck, E.; Calmels, L.; Serin, V.; Schattschneider, P.; Jacob, D.; Cordier, P.

    2007-01-01

    This document gathers the resumes of some of the presentations made at this conference whose aim was to present the last developments and achievements of the 3 complementary microscopies: optical microscopy, electron microscopy and X-ray microscopy. The contributions have been organized around the following 12 topics: 1) new technical developments, 2) 3-dimensional imaging, 3) quantitative microscopy, 4) technical progress in photon microscopy, 5) synchrotron radiation, 6) measurements of patterns, deformations and strains, 7) materials for energy and transports, 8) nano-structures, 9) virus: structure and infection mechanisms, 10) 3-dimensional imaging for molecules, cells and cellular tissues, 11) nano-particles and colloids, and 12) liquid crystals

  13. X-ray microscopy in Aarhus

    International Nuclear Information System (INIS)

    Uggerhoej, Erik; Abraham-Peskir, Joanna V.

    2000-01-01

    The Aarhus imaging soft X-ray microscope is now a busy multi-user facility. The optical set-up will be described and project highlights discussed. a) Metal-induced structural changes in whole cells in solution. The effects of aluminum, copper, nickel and zinc on protozoa investigated by using a combination of light microscopy, confocal scanning laser microscopy and X-ray microscopy. b) Botanical studies by X-ray microscopy used to compliment electron microscopy studies. c) Sludge morphology and iron precipitation in Danish freshwater plants by combining X-ray, scanning electron and transmission electron microscopy

  14. Comparison of confocal microscopy and two-photon microscopy in mouse cornea in vivo.

    Science.gov (United States)

    Lee, Jun Ho; Lee, Seunghun; Gho, Yong Song; Song, In Seok; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2015-03-01

    High-resolution imaging of the cornea is important for studying corneal diseases at cellular levels. Confocal microscopy (CM) has been widely used in the clinic, and two-photon microscopy (TPM) has recently been introduced in various pre-clinical studies. We compared the performance of CM and TPM in normal mouse corneas and neovascularized mouse corneas induced by suturing. Balb/C mice and C57BL/6 mice expressing green fluorescent protein (GFP) were used to compare modalities based on intrinsic contrast and extrinsic fluorescence contrast. CM based on reflection (CMR), CM based on fluorescence (CMF), and TPM based on intrinsic/extrinsic fluorescence and second harmonic generation (SHG) were compared by imaging the same sections of mouse corneas sequentially in vivo. In normal mouse corneas, CMR visualized corneal cell morphologies with some background noise, and CMF visualized GFP expressing corneal cells clearly. TPM visualized corneal cells and collagen in the stroma based on fluorescence and SHG, respectively. However, in neovascularized mouse corneas, CMR could not resolve cells deep inside the cornea due to high background noise from the effects of increased structural irregularity induced by suturing. CMF and TPM visualized cells and induced vasculature better than CMR because both collect signals from fluorescent cells only. Both CMF and TPM had signal decays with depth due to the structural irregularity, with CMF having faster signal decay than TPM. CMR, CMF, and TPM showed different degrees of image degradation in neovascularized mouse corneas. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Dark-field X-ray microscopy for multiscale structural characterization

    DEFF Research Database (Denmark)

    Simons, Hugh; King, A.; Ludwig, W.

    2015-01-01

    Many physical and mechanical properties of crystalline materials depend strongly on their internal structure, which is typically organized into grains and domains on several length scales. Here we present dark-field X-ray microscopy; a non-destructive microscopy technique for the three...... of the interactions between crystalline elements is a key step towards the formulation and validation of multiscale models that account for the entire heterogeneity of a material. Furthermore, dark-field X-ray microscopy is well suited to applied topics, where the structural evolution of internal nanoscale elements...

  16. Reflections on Miniature Golf.

    Science.gov (United States)

    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)

  17. Seasonal soybean crop reflectance

    Science.gov (United States)

    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.

  18. Reflectance Reference Targets (OTTER)

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Spectral reflectance measurements of flat field targets as reference points representative of pseudo-invariant targets as measured by Spectron SE590...

  19. Reflectance Reference Targets (OTTER)

    Data.gov (United States)

    National Aeronautics and Space Administration — Spectral reflectance measurements of flat field targets as reference points representative of pseudo-invariant targets as measured by Spectron SE590 spectrophotometer

  20. Visual-servoing optical microscopy

    Science.gov (United States)

    Callahan, Daniel E.; Parvin, Bahram

    2009-06-09

    The present invention provides methods and devices for the knowledge-based discovery and optimization of differences between cell types. In particular, the present invention provides visual servoing optical microscopy, as well as analysis methods. The present invention provides means for the close monitoring of hundreds of individual, living cells over time: quantification of dynamic physiological responses in multiple channels; real-time digital image segmentation and analysis; intelligent, repetitive computer-applied cell stress and cell stimulation; and the ability to return to the same field of cells for long-term studies and observation. The present invention further provides means to optimize culture conditions for specific subpopulations of cells.

  1. Advances in multiphoton microscopy technology

    Science.gov (United States)

    Hoover, Erich E.; Squier, Jeff A.

    2013-01-01

    Multiphoton microscopy has enabled unprecedented dynamic exploration in living organisms. A significant challenge in biological research is the dynamic imaging of features deep within living organisms, which permits the real-time analysis of cellular structure and function. To make progress in our understanding of biological machinery, optical microscopes must be capable of rapid, targeted access deep within samples at high resolution. In this Review, we discuss the basic architecture of a multiphoton microscope capable of such analysis and summarize the state-of-the-art technologies for the quantitative imaging of biological phenomena. PMID:24307915

  2. Microscopy using randomized speckle illumination

    Science.gov (United States)

    Perinchery, Sandeep M.; Shinde, Anant; Murukeshan, V. M.

    2017-06-01

    It is well known for structured illumination microscopy (SIM) that the lateral resolution by a factor of two beyond the classical diffraction limit is achieved using spatially structured illumination in wide-field fluorescence microscope. In the state of art SIM systems, grating patterns are generally generated by physical gratings or by spatial light modulators such as digital micro mirrors (DMD), liquid crystal displays (LCD). In this study, using a combination of LCD and ground glasses, size controlled randomized speckle patterns are generated as an illumination source for the microscope. Proof of concept of using speckle illumination in SIM configuration is tested by imaging fixed BPAE cells.

  3. Thoughts on Reflection (Editorial

    Directory of Open Access Journals (Sweden)

    Denise Koufogiannakis

    2010-06-01

    Full Text Available There has been some acknowledgement in the published literature that reflection is a crucial element of the evidence based library and information practice (EBLIP model we have adopted (Booth 2004, 2006; Grant 2007; Helliwell 2007. As we work through a problem and try to incorporate the best available evidence into our decision making, reflection is required at several stages, including the very identification of the problem through to our assessment of the process itself and what we have learned in order to inform future practice. However, reflection and reflective writing have not fully been integrated into the process we espouse, and very little has been done to look more closely at this element of the model and how it can be integrated into professional learning.In a recently published research article, Sen (2010 confirms the relationship between reflection and several aspects of professional practice. These include critical review and decision making, two aspects that are tied closely to the evidence based process. Sen notes: Students were more likely to show evidence of learning, self‐development, the ability to review issues crucially, awareness of their own mental functions, ability to make decision [sic] and being empowered when they had mastered the art of reflective practice and the more deeply analytical reflective writing. (p.84 EBLIP (the journal tries to incorporate elements of reflection within the articles we publish. While we clearly believe in the need for our profession to do quality research and publish that research so that it can be accessible to practitioners, we also know that research cannot be looked at in isolation. Our evidence summaries are one way of reflecting critically on previously published research, and in the same vein, our classics bring older research studies back to the foreground. This work needs to continue to be discussed and looked at for its impact on our profession.More directly, the Using

  4. Polyethyleneimine as tracer for electron microscopy

    NARCIS (Netherlands)

    Schurer, Jacob Willem

    1980-01-01

    In this thesis the development of a tracer particle for use in electron microscopy is described. Attempts were made to use this tracer particle in immuno-electron microscopy and to trace negatively charged tissue components. ... Zie: Summary

  5. NICHD Microscopy and Imaging Core (MIC)

    Data.gov (United States)

    Federal Laboratory Consortium — The NICHD Microscopy and Imaging Core (MIC) is designed as a multi-user research facility providing training and instrumentation for high resolution microscopy and...

  6. Comparison between direct methods for determination of microbial cell volume: electron microscopy and electronic particle sizing.

    OpenAIRE

    Montesinos, E; Esteve, I; Guerrero, R

    1983-01-01

    Size frequency distributions of different phototrophic and heterotrophic microorganisms were determined by means of scanning and transmission electron microscopy and electronic particle sizing. Statistically significant differences existed among the three techniques used in this study. Cells processed for electron microscopy showed lower mean cellular volumes than those processed for electronic particle sizing, reflecting a shrinkage by factors ranging from 1.1 to 6.2 (mean, 2.3). Processing ...

  7. Electron Microscopy Society of Southern Africa : proceedings

    International Nuclear Information System (INIS)

    Snyman, H.C.; Coetzee, J.; Coubrough, R.I.

    1987-01-01

    The proceedings of the 26th annual conference of the Electron Microscopy Society of Southern Africa are presented. Papers were presented on the following topics: techniques and instrumentation used in electron microscopy, and applications of electron microscopy in the life sciences, including applications in medicine, zoology, botany and microbiology. The use of electron microscopy in the physical sciences was also discussed. Separate abstracts were prepared for seven of the papers presented. The remaining papers were considered outside the subject scope of INIS

  8. International health law : an emerging field of public international law

    NARCIS (Netherlands)

    Toebes, Brigit

    This article discusses the nature and scope of international health law as an emerging field of public international law. It is argued that the protection of health reflects a pressing social need that should now be spoken of in the vocabulary of international law. Furthermore, there is an urgent

  9. Agreement between direct fluorescent microscopy and Ziehl ...

    African Journals Online (AJOL)

    Background: The sensitivity of smear microscopy for diagnosis of tuberculosis might be improved through treatment of sputum with sodium hypochlorite and application of fluorescent microscopy. This study aimed to determine the agreement between direct Fluorescent Microscopy and Ziehl-Neelsen concentration technique ...

  10. Plasmonics Enhanced Smartphone Fluorescence Microscopy

    KAUST Repository

    Wei, Qingshan

    2017-05-12

    Smartphone fluorescence microscopy has various applications in point-of-care (POC) testing and diagnostics, ranging from e.g., quantification of immunoassays, detection of microorganisms, to sensing of viruses. An important need in smartphone-based microscopy and sensing techniques is to improve the detection sensitivity to enable quantification of extremely low concentrations of target molecules. Here, we demonstrate a general strategy to enhance the detection sensitivity of a smartphone-based fluorescence microscope by using surface-enhanced fluorescence (SEF) created by a thin metal-film. In this plasmonic design, the samples are placed on a silver-coated glass slide with a thin spacer, and excited by a laser-diode from the backside through a glass hemisphere, generating surface plasmon polaritons. We optimized this mobile SEF system by tuning the metal-film thickness, spacer distance, excitation angle and polarization, and achieved ~10-fold enhancement in fluorescence intensity compared to a bare glass substrate, which enabled us to image single fluorescent particles as small as 50 nm in diameter and single quantum-dots. Furthermore, we quantified the detection limit of this platform by using DNA origami-based brightness standards, demonstrating that ~80 fluorophores per diffraction-limited spot can be readily detected by our mobile microscope, which opens up new opportunities for POC diagnostics and sensing applications in resource-limited-settings.

  11. Cluster computing for digital microscopy.

    Science.gov (United States)

    Carrington, Walter A; Lisin, Dimitri

    2004-06-01

    Microscopy is becoming increasingly digital and dependent on computation. Some of the computational tasks in microscopy are computationally intense, such as image restoration (deconvolution), some optical calculations, image segmentation, and image analysis. Several modern microscope technologies enable the acquisition of very large data sets. 3D imaging of live cells over time, multispectral imaging, very large tiled 3D images of thick samples, or images from high throughput biology all can produce extremely large images. These large data sets place a very large burden on laboratory computer resources. This combination of computationally intensive tasks and larger data sizes can easily exceed the capability of single personal computers. The large multiprocessor computers that are the traditional technology for larger tasks are too expensive for most laboratories. An alternative approach is to use a number of inexpensive personal computers as a cluster; that is, use multiple networked computers programmed to run the problem in parallel on all the computers in the cluster. By the use of relatively inexpensive over-the-counter hardware and open source software, this approach can be much more cost effective for many tasks. We discuss the different computer architectures available, and their advantages and disadvantages. Copyright 2004 Wiley-Liss, Inc.

  12. Multifunctional scanning ion conductance microscopy.

    Science.gov (United States)

    Page, Ashley; Perry, David; Unwin, Patrick R

    2017-04-01

    Scanning ion conductance microscopy (SICM) is a nanopipette-based technique that has traditionally been used to image topography or to deliver species to an interface, particularly in a biological setting. This article highlights the recent blossoming of SICM into a technique with a much greater diversity of applications and capability that can be used either standalone, with advanced control (potential-time) functions, or in tandem with other methods. SICM can be used to elucidate functional information about interfaces, such as surface charge density or electrochemical activity (ion fluxes). Using a multi-barrel probe format, SICM-related techniques can be employed to deposit nanoscale three-dimensional structures and further functionality is realized when SICM is combined with scanning electrochemical microscopy (SECM), with simultaneous measurements from a single probe opening up considerable prospects for multifunctional imaging. SICM studies are greatly enhanced by finite-element method modelling for quantitative treatment of issues such as resolution, surface charge and (tip) geometry effects. SICM is particularly applicable to the study of living systems, notably single cells, although applications extend to materials characterization and to new methods of printing and nanofabrication. A more thorough understanding of the electrochemical principles and properties of SICM provides a foundation for significant applications of SICM in electrochemistry and interfacial science.

  13. Multifunctional scanning ion conductance microscopy

    Science.gov (United States)

    Page, Ashley; Unwin, Patrick R.

    2017-01-01

    Scanning ion conductance microscopy (SICM) is a nanopipette-based technique that has traditionally been used to image topography or to deliver species to an interface, particularly in a biological setting. This article highlights the recent blossoming of SICM into a technique with a much greater diversity of applications and capability that can be used either standalone, with advanced control (potential–time) functions, or in tandem with other methods. SICM can be used to elucidate functional information about interfaces, such as surface charge density or electrochemical activity (ion fluxes). Using a multi-barrel probe format, SICM-related techniques can be employed to deposit nanoscale three-dimensional structures and further functionality is realized when SICM is combined with scanning electrochemical microscopy (SECM), with simultaneous measurements from a single probe opening up considerable prospects for multifunctional imaging. SICM studies are greatly enhanced by finite-element method modelling for quantitative treatment of issues such as resolution, surface charge and (tip) geometry effects. SICM is particularly applicable to the study of living systems, notably single cells, although applications extend to materials characterization and to new methods of printing and nanofabrication. A more thorough understanding of the electrochemical principles and properties of SICM provides a foundation for significant applications of SICM in electrochemistry and interfacial science. PMID:28484332

  14. Light Sheet Fluorescence Microscopy (LSFM).

    Science.gov (United States)

    Adams, Michael W; Loftus, Andrew F; Dunn, Sarah E; Joens, Matthew S; Fitzpatrick, James A J

    2015-01-05

    The development of confocal microscopy techniques introduced the ability to optically section fluorescent samples in the axial dimension, perpendicular to the image plane. These approaches, via the placement of a pinhole in the conjugate image plane, provided superior resolution in the axial (z) dimension resulting in nearly isotropic optical sections. However, increased axial resolution, via pinhole optics, comes at the cost of both speed and excitation efficiency. Light sheet fluorescent microscopy (LSFM), a century-old idea made possible with modern developments in both excitation and detection optics, provides sub-cellular resolution and optical sectioning capabilities without compromising speed or excitation efficiency. Over the past decade, several variations of LSFM have been implemented each with its own benefits and deficiencies. Here we discuss LSFM fundamentals and outline the basic principles of several major light-sheet-based imaging modalities (SPIM, inverted SPIM, multi-view SPIM, Bessel beam SPIM, and stimulated emission depletion SPIM) while considering their biological relevance in terms of intrusiveness, temporal resolution, and sample requirements. Copyright © 2015 John Wiley & Sons, Inc.

  15. Lensfree optofluidic microscopy and tomography.

    Science.gov (United States)

    Bishara, Waheb; Isikman, Serhan O; Ozcan, Aydogan

    2012-02-01

    Microfluidic devices aim at miniaturizing, automating, and lowering the cost of chemical and biological sample manipulation and detection, hence creating new opportunities for lab-on-a-chip platforms. Recently, optofluidic devices have also emerged where optics is used to enhance the functionality and the performance of microfluidic components in general. Lensfree imaging within microfluidic channels is one such optofluidic platform, and in this article, we focus on the holographic implementation of lensfree optofluidic microscopy and tomography, which might provide a simpler and more powerful solution for three-dimensional (3D) on-chip imaging. This lensfree optofluidic imaging platform utilizes partially coherent digital in-line holography to allow phase and amplitude imaging of specimens flowing through micro-channels, and takes advantage of the fluidic flow to achieve higher spatial resolution imaging compared to a stationary specimen on the same chip. In addition to this, 3D tomographic images of the same samples can also be reconstructed by capturing lensfree projection images of the samples at various illumination angles as a function of the fluidic flow. Based on lensfree digital holographic imaging, this optofluidic microscopy and tomography concept could be valuable especially for providing a compact, yet powerful toolset for lab-on-a-chip devices.

  16. Automatic specular reflections removal for endoscopic images

    Science.gov (United States)

    Tan, Ke; Wang, Bin; Gao, Yuan

    2017-07-01

    Endoscopy imaging is utilized to provide a realistic view about the surfaces of organs inside the human body. Owing to the damp internal environment, these surfaces usually have a glossy appearance showing specular reflections. For many computer vision algorithms, the highlights created by specular reflections may become a significant source of error. In this paper, we present a novel method for restoration of the specular reflection regions from a single image. Specular restoration process starts with generating a substitute specular-free image with RPCA method. Then the specular removed image was obtained by taking the binary weighting template of highlight regions as the weighting for merging the original specular image and the substitute image. The modified template was furthermore discussed for the concealment of artificial effects in the edge of specular regions. Experimental results on the removal of the endoscopic image with specular reflections demonstrate the efficiency of the proposed method comparing to the existing methods.

  17. Kelvin probe force microscopy in liquid using electrochemical force microscopy.

    Science.gov (United States)

    Collins, Liam; Jesse, Stephen; Kilpatrick, Jason I; Tselev, Alexander; Okatan, M Baris; Kalinin, Sergei V; Rodriguez, Brian J

    2015-01-01

    Conventional closed loop-Kelvin probe force microscopy (KPFM) has emerged as a powerful technique for probing electric and transport phenomena at the solid-gas interface. The extension of KPFM capabilities to probe electrostatic and electrochemical phenomena at the solid-liquid interface is of interest for a broad range of applications from energy storage to biological systems. However, the operation of KPFM implicitly relies on the presence of a linear lossless dielectric in the probe-sample gap, a condition which is violated for ionically-active liquids (e.g., when diffuse charge dynamics are present). Here, electrostatic and electrochemical measurements are demonstrated in ionically-active (polar isopropanol, milli-Q water and aqueous NaCl) and ionically-inactive (non-polar decane) liquids by electrochemical force microscopy (EcFM), a multidimensional (i.e., bias- and time-resolved) spectroscopy method. In the absence of mobile charges (ambient and non-polar liquids), KPFM and EcFM are both feasible, yielding comparable contact potential difference (CPD) values. In ionically-active liquids, KPFM is not possible and EcFM can be used to measure the dynamic CPD and a rich spectrum of information pertaining to charge screening, ion diffusion, and electrochemical processes (e.g., Faradaic reactions). EcFM measurements conducted in isopropanol and milli-Q water over Au and highly ordered pyrolytic graphite electrodes demonstrate both sample- and solvent-dependent features. Finally, the feasibility of using EcFM as a local force-based mapping technique of material-dependent electrostatic and electrochemical response is investigated. The resultant high dimensional dataset is visualized using a purely statistical approach that does not require a priori physical models, allowing for qualitative mapping of electrostatic and electrochemical material properties at the solid-liquid interface.

  18. Kelvin probe force microscopy in liquid using electrochemical force microscopy

    Directory of Open Access Journals (Sweden)

    Liam Collins

    2015-01-01

    Full Text Available Conventional closed loop-Kelvin probe force microscopy (KPFM has emerged as a powerful technique for probing electric and transport phenomena at the solid–gas interface. The extension of KPFM capabilities to probe electrostatic and electrochemical phenomena at the solid–liquid interface is of interest for a broad range of applications from energy storage to biological systems. However, the operation of KPFM implicitly relies on the presence of a linear lossless dielectric in the probe–sample gap, a condition which is violated for ionically-active liquids (e.g., when diffuse charge dynamics are present. Here, electrostatic and electrochemical measurements are demonstrated in ionically-active (polar isopropanol, milli-Q water and aqueous NaCl and ionically-inactive (non-polar decane liquids by electrochemical force microscopy (EcFM, a multidimensional (i.e., bias- and time-resolved spectroscopy method. In the absence of mobile charges (ambient and non-polar liquids, KPFM and EcFM are both feasible, yielding comparable contact potential difference (CPD values. In ionically-active liquids, KPFM is not possible and EcFM can be used to measure the dynamic CPD and a rich spectrum of information pertaining to charge screening, ion diffusion, and electrochemical processes (e.g., Faradaic reactions. EcFM measurements conducted in isopropanol and milli-Q water over Au and highly ordered pyrolytic graphite electrodes demonstrate both sample- and solvent-dependent features. Finally, the feasibility of using EcFM as a local force-based mapping technique of material-dependent electrostatic and electrochemical response is investigated. The resultant high dimensional dataset is visualized using a purely statistical approach that does not require a priori physical models, allowing for qualitative mapping of electrostatic and electrochemical material properties at the solid–liquid interface.

  19. CCD-based thermoreflectance microscopy: principles and applications

    International Nuclear Information System (INIS)

    Farzaneh, M; Maize, K; Shakouri, A; Lueerssen, D; Summers, J A; Hudgings, Janice A; Mayer, P M; Ram, R J; Raad, P E; Pipe, K P

    2009-01-01

    CCD-based thermoreflectance microscopy has emerged as a high resolution, non-contact imaging technique for thermal profiling and performance and reliability analysis of numerous electronic and optoelectronic devices at the micro-scale. This thermography technique, which is based on measuring the relative change in reflectivity of the device surface as a function of change in temperature, provides high-resolution thermal images that are useful for hot spot detection and failure analysis, mapping of temperature distribution, measurement of thermal transient, optical characterization of photonic devices and measurement of thermal conductivity in thin films. In this paper we review the basic physical principle behind thermoreflectance as a thermography tool, discuss the experimental setup, resolutions achieved, signal processing procedures and calibration techniques, and review the current applications of CCD-based thermoreflectance microscopy in various devices. (topical review)

  20. Diffuse reflection of ultracold neutrons from low-roughness surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Atchison, F.; Daum, M.; Henneck, R.; Horisberger, M.; Kirch, K.; Lauss, B.; Mtchedlishvili, A.; Meier, M.; Petzoldt, G.; Schelldorfer, R.; Zsigmond, G. [Paul Scherrer Institut, PSI, Villigen (Switzerland); Heule, S.; Knecht, A. [Paul Scherrer Institut, PSI, Villigen (Switzerland); University Zuerich, Zuerich (Switzerland); Kasprzak, M. [Paul Scherrer Institut, PSI, Villigen (Switzerland); Stefan Meyer Institut, Vienna (Austria); Kuzniak, M. [Paul Scherrer Institut, PSI, Villigen (Switzerland); Jagiellonian University, Smoluchowski Institute of Physics, Cracow (Poland); Plonka-Spehr, C. [Institut Laue Langevin, ILL, Grenoble (France); Straumann, U. [University Zuerich, Zuerich (Switzerland)

    2010-04-15

    We report a measurement of the reflection of ultracold neutrons from flat, large-area plates of different Fermi potential materials with low surface roughness. The results were used to test two diffuse reflection models, the well-known Lambert model and the micro-roughness model which is based on wave scattering. The Lambert model fails to reproduce the diffuse reflection data. The surface roughness b and correlation length w, obtained by fitting the micro-roughness model to the data are in the range 1{<=}b{<=}3 nm and 10{<=}w{<=}120 nm, in qualitative agreement with independent measurements using atomic force microscopy. (orig.)