3,516 research outputs found

    Quantitative and Computer Assisted Electron Microscopic and Microprobe Studies in Dermatology

    Get PDF
    Electron microscopes are not yet routine instruments in modern dermatological pathology even though they have provided detailed data about pathological changes in the skin for more than three decades. At present, dermatopathology is still dominated by light microscopy and especially so since the introduction of immunological techniques such as the use of monoclonal antibodies. These tools applied at electron microscopic resolution, however, may provide the ultimate identification of cells and subcellular components. In addition, electron microscopes have no peers in areas of quantitative investigation at subcellular levels, e.g. morphometry. The electron microprobe provides a unique tool in elemental analysis and may be used for the analysis of conventonally prepared specimens when foreign matter, not soluble in water, is deposited in the tissue. On the other hand, with water soluble substances the technique is most effective when freeze sections are utilized. This paper gives a selected review of the present day status of quantitative skin research as analysed with electron microscopy and the related technique of electron microprobe analysis

    A Survey of Electron Probe Microanalysis Using Soft Radiations: Difficulties and Presentation of a New Computer Program for Wavelength Dispersive Spectrometry

    Get PDF
    This paper aims to demonstrate that on-line peak integral technique with wavelength dispersive spectroscopy (WDS) provides accurate results with intensity measurement counting times as short as one or two minutes, owing to the high counting rates obtained with multilayer analyzers. A great advantage of a new computer program using this technique (available on SUN/UNIX work-stations operating Cameca SX-50 microprobes) consists in the original way that peak overlaps are treated. For each analytical point, overlapping counts emerging from an element B (B counts) are removed on-line from the measured raw counts in order to obtain the net counts corresponding to the element to be analyzed (element A). B counts are first measured on a proper standard containing B but not A. The effects of chemical bonding on the shape and the shift of peaks is clearly seen in the analysis of fluorine in topaz and lithium fluoride. Self-absorption effects, which usually distort the high energy side of L-series soft radiations, are generally inconsistent with the direct measurements of peak area fork-ratio determination. A method based on the conventional area/peak factor concept is proposed for this purpose

    Image Analysis and X-Ray Microanalysis in Cytochemistry

    Get PDF
    When cytochemical reaction products are homogeneously distributed within an organelle, point analyses suffice for the quantitative approach. However, quantitative analysis becomes tedious, when the elements in the reaction product are inhomogeneously distributed. Problems arise when elements from two reaction products have to be related to each other, or to endogenous cytological products (ferritin, haemosiderin, calcium, electron dense markers), either topographically or in concentration. When analyzing inhomogeneous/heteromorphical reaction product-containing organelles special attention has to be paid to measure and relate both volume and concentration. In this paper a relative simple structure (eosinophil granules) is chosen to demonstrate that the acquisition of the requested morphometrical plus chemical information and their integration is possible. The following points will be covered to acquire the morphometrical and chemical information: a). How to estimate the total cell cross-sectioned area. b). How to estimate the total cross-sectioned area of all reaction product-containing particles inside that cell. The ratio of these two areas will provide the requested information about the particle volume fraction. By using the X-ray detector in addition: c). How to acquire the chemical information at the requested resolution, within a reasonable total acquisition time d). How to integrate the morphometrical and chemical data per organelle, by matrix analysis in a reduced scan area. e). How to acquire quantitative chemical information, by the use of cross-sectioned standards. f). How to make this acquisition method independent from changes in the instrumental conditions during the acquisition

    Annual Report Fiscal Year 2004-2005

    Get PDF
    https://digitalcommons.memphis.edu/govpubs-tn-bureau-investigation-annual-reports/1017/thumbnail.jp

    Annual Report Fiscal Year 2005-2006

    Get PDF
    https://digitalcommons.memphis.edu/govpubs-tn-bureau-investigation-annual-reports/1016/thumbnail.jp

    Redesigning Check-Processing Operations Using Animated Computer Simulation

    Get PDF
    This paper describes the steps taken by a major commercial bank in the USA to redesign a critical function within its check-processing operation. Animated simulation models of the current and new process were developed to understand the relationship between process parameters waiting times and productivity measures. We describe the animated simulation modeling approach in detail present sample results and provide directions for further use of such an approach in banking

    Interactive Virtual Scanning Electron Microscope Inspired by 3D Game-Design

    Get PDF
    The scanning electron microscope (SEM) has evolved to become an indispensable tool for research and education in engineering, physics, nanotechnology, geosciences, materials science, biological sciences and other fields. However, training on a physical SEM is costly, time consuming, and often unavailable in economically disadvantaged areas. Advances in computer technology have made interactive three-dimensional (3D) virtual laboratory an effective tool for training in medicine and many engineering and technology fields. In the current work, in order to provide cost-effective hands-on training, a virtual 3D SEM was developed using the game development engine Unity 3D. It contains realistic 3D models of the physical components, created using 3ds Max®, a software for 3D modeling and rendering. The components are manipulated with scripts programmed using C# and JavaScript and then paired with the corresponding model. Users may view and operate the virtual instrument, save images for further analysis, and write a report. The developed virtual SEM was tested on diverse groups of users at multiple institutions, each divided to treatment and control groups. Feedback from these tests was collected and used for improvements in the overall quality of the simulated experience. In addition, users reported the experience of training on the virtual SEM as enjoyable

    Annual Report Fiscal Year 2006-2007

    Get PDF
    https://digitalcommons.memphis.edu/govpubs-tn-bureau-investigation-annual-reports/1015/thumbnail.jp
    • …
    corecore