Sample records for virtual petrological microscope

  1. A virtual petrological microscope for teaching and outreach

    Microsoft Academic Search

    Simon P. Kelley; Peter Whalley; Andrew G. Tindle; Mahesh Anand

    2010-01-01

    Learning to use microscopes for geoscience or life science applications is a crucial part of the practical training offered in many science degrees, but the opportunities to study are often constrained by available laboratory space and time, and sometimes constrained by the number of high quality microscopes available. The alternative, although not replacing physical microscopes, offers the opportunity for enhancement

  2. Assessment of Petrological Microscopes.

    ERIC Educational Resources Information Center

    Mathison, Charter Innes

    1990-01-01

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

  3. Virtual Microscope

    NSDL National Science Digital Library

    The Virtual Microscope is a NASA-funded project that provides simulated scientific instrumentation for students and researchers worldwide as part of NASA's Virtual Laboratory initiative. This site serves as home base for the Imaging Technology Group's contributions to that project- namely virtual microscopes and the multi-dimensional, high-resolution image datasets they view. Currently we provide 90 samples totaling over 62 gigapixels of image data. The Virtual Microscope, which is available for free download, supports functionality from electron, light, and scanning probe microscopes, datasets for these instruments, training materials to learn more about microscopy, and other related tools. The project is open source and the code is available on Sourceforge.

  4. Virtual Microscope for Earth Sciences

    NSDL National Science Digital Library

    Simon Kelley

    The Virtual Microscope was developed for undergraduate teaching of petrology and geoscience at the Open University in the United Kingdom, allowing students to explore rock hand specimens and thin sections in a browser window. Collections include petrographic images of terrestrial, extraterrestrial and rare rock collections.

  5. Virtual petrological microscopy: web 2.0 technology for learning microscopy skills outside the laboratory

    Microsoft Academic Search

    S. P. Kelley; P. Whalley; A. Tindle

    2009-01-01

    Learning to use microscopes for geoscience or life science applications is a crucial part of the practical training offered in many science degrees, but the opportunities to study are often constrained by available laboratory space and time, and sometimes constrained by the number of high quality microscopes available. We will demonstrate a new based virtual petrological microscope which offers the

  6. Virtual Compound Microscope

    NSDL National Science Digital Library

    Ketcham, Robert

    Virtual Microscopy is a very handy online tool to learn how to use a microscope. The creator developed this tool in response to student frustration in learning how to use microscopes. The virtual scope has all the same controls found on the real unit and the user can learn the parts of the microscope as well as how to adjust the different objectives, course and fine focus, and make light adjustments with the iris diaphragm. Of particular interest is the fact that the simulation shows actual microscope specimens, like onion root tip, so students can see what mitotic figures look like under the microscope without having to be expert users. Of course, a simulation does not take the place of using the actual microscope but can certainly shorten the time that it takes to learn how to use one, and lessen the amount of frustration for both student and teacher.

  7. The Virtual Microscope

    NSDL National Science Digital Library

    Benyon, Michael P.

    The work of pathologists is often limited by the supply of tissue samples and live specimens they have on hand. This paper addresses this problem by proposing the Virtual Microscope (VM), a software-based solution that digitally records images of magnified slides. In this manner, a scientist would only need to search a database of digital slides instead of hoping to find another slide of the required sample. The VM is created in such a way as to simulate a real microscope, allowing the user to change illumination levels, focus, and magnification factor. The authors describe the architecture and different configurations of the VM system, as well as addressing potential problems due to the massive amount of data required for a single digital slide.

  8. Virtual pinhole confocal microscope

    SciTech Connect

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

    1999-06-01

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

  9. Inquiry based learning with a virtual microscope

    NASA Astrophysics Data System (ADS)

    Kelley, S. P.; Sharples, M.; Tindle, A.; Villasclaras-Fernández, E.

    2012-12-01

    As part of newly funded initiative, the Wolfson OpenScience Laboratory, we are linking a tool for inquiry based learning, nQuire (http://www.nquire.org.uk) with the virtual microscope for Earth science (http://www.virtualmicroscope.co.uk) to allow students to undertake projects and gain from inquiry based study thin sections of rocks without the need for a laboratory with expensive petrological microscopes. The Virtual Microscope (VM) was developed for undergraduate teaching of petrology and geoscience, allowing students to explore rock hand specimens and thin sections in a browser window. The system is based on HTML5 application and allows students to scan and zoom the rocks in a browser window, view in ppl and xpl conditions, and rotate specific areas to view birefringence and pleochroism. Importantly the VM allows students to gain access to rare specimens such as Moon rocks that might be too precious to suffer loss or damage. Experimentation with such specimens can inspire the learners' interest in science and allows them to investigate relevant science questions. Yet it is challenging for learners to engage in scientific processes, as they may lack scientific investigation skills or have problems in planning their activities; for teachers, managing inquiry activities is a demanding task (Quintana et al., 2004). To facilitate the realization of inquiry activities, the VM is being integrated with the nQuire tool. nQuire is a web tool that guides and supports students through the inquiry process (Mulholland et al., 2011). Learners are encouraged to construct their own personally relevant hypothesis, pose scientific questions, and plan the method to answer them. Then, the system enables users to collect and analyze data, and share their conclusions. Teachers can monitor their students' progress through inquiries, and give them access to new parts of inquiries as they advance. By means of the integration of nQuire and the VM, inquiries that involve collecting data through a microscope can be created and supported. To illustrate the possibilities of these tools, we have designed two inquiries that engage learners in the study of Moon rock samples under the microscope, starting from general questions such as comparison of Moon rocks or determining the origin of meteorites. One is aimed at undergraduate Geology students; the second has been conceived for the general public. Science teachers can reuse these inquiries, adapt them as they need, or create completely new inquiries using nQuire's authoring tool. We will report progress and demonstrate the combination of these two on-line tools to create an open educational resource allowing educators to design and run science inquiries for Earth and planetary science in a range of settings from schools to universities. Quintana, C., Reiser, B. J., Davis, E. A., Krajcik, J., Fretz, E., Duncan, R. G., Kyza, E., et al. (2004). A scaffolding design framework for software to support science inquiry. Journal of the Learning Sciences, 13(3), 337-386. Mulholland, P., Anastopoulou, S., Collins, T., FeiBt, M., Gaved, M., Kerawalla, L., Paxton, M., et al. (2011). nQuire: Technological support for personal inquiry learning. IEEE Transactions on Learning Technologies. First published online, December 5, 2011, http://doi.ieeecomputersociety.org/10.1109/TLT.2011.32.

  10. Virtual laboratory manual for microscopic anatomy.

    PubMed

    Michaels, John E; Allred, Kelly; Bruns, Christina; Lim, Wan; Lowrie, D J; Hedgren, Wade

    2005-05-01

    Using digital technology, we have assembled a virtual laboratory manual (VLM) that is a Web-based copy of our traditional laboratory manual. The VLM is used to enhance traditional laboratory instruction in histology. For each reference in the VLM to either a histological slide or an electron micrograph (EM), hyperlinks are included that download digital images derived from the students' glass slide sets or scanned EMs. The VLM serves as an atlas of digital images for concurrent study of similar sections by light microscopy during laboratory sessions. In addition, students can review the images from the VLM at remote locations. We have encouraged continued use of light microscopes in laboratories by basing the majority of practical examination identifications on analysis of marked histological slides that require students to use their own microscopes. The VLM provides the convenience of a Web-based resource with high-quality images, yet allows retention of the many excellent traditional aspects of our course. An example of a VLM laboratory on epithelium is available online (http://users.von.uc.edu/michaeje/VLM-Epithelium/exLab4.pdf). PMID:15898084

  11. The Role of the Virtual Microscope in Distance Learning

    ERIC Educational Resources Information Center

    Whalley, Peter; Kelley, Simon; Tindle, Andrew

    2011-01-01

    Screen-based microscopes allow for a shared visualisation and task-directed conversations that offer significant pedagogic advantages for the science disciplines involving observation of natural samples such as the geosciences and biosciences, and particularly for distance education in these disciplines. The role and development of a virtual

  12. Virtual Reality in Biological Microscopic Imaging R. v Liere, W. de Leeuw, J. Mulder

    E-print Network

    Liere, Robert van

    Virtual Reality in Biological Microscopic Imaging R. v Liere, W. de Leeuw, J. Mulder Department addresses the role of virtual reality in gaining insight in these presentations. The understanding. Perceiving these charac- teristics is enhanced by using virtual reality technology. The advantage of virtual

  13. Teaching medical histology at the University of South Carolina School of Medicine: Transition to virtual slides and virtual microscopes.

    PubMed

    Blake, Charles A; Lavoie, Holly A; Millette, Clarke F

    2003-12-01

    We describe how the histology course we teach to first-year medical students changed successfully from using glass slides and microscopes to using virtual slides and virtual microscopes. In 1988, we taught a classic medical histology course. Subsequently, students were loaned static labeled images on projection slides to introduce them to their microscope glass slides, and we made laser disks of histological images available in the teaching lab. In 2000, we placed the static labeled images and laboratory manual on the Web. We abandoned the Web-based approach in 2001. Faculty selected specific areas on microscope glass slides in student collections for scanning at a total magnification of 40, 100, 200, or 400. Christopher M. Prince of Petro Image, LLC, scanned the glass slides; digitized, encoded, and compressed (95%) the images; and placed them on CD-ROMs. The scanned images were viewed up to a magnification of 400 using the MrSID viewer (LizardTech software) and the computer as a virtual microscope. This viewer has many useful features, including effective microscope and telescope functions that provide greater versatility for sample study and speed in localizing structures than was possible with the actual microscope. Image detail is indistinguishable from that viewed under the light microscope at equivalent magnifications. Static labeled images were also placed on CD-ROMs to introduce students to the virtual slides. Students could view all the images on their CD-ROMs at any time and in any place with their laptop computers without going online. Students no longer rented light microscopes in 2002. Both students and faculty have shown strong support for using this approach to teaching histology during the past 2 years. PMID:14628320

  14. Construction of a Virtual Scanning Electron Microscope (VSEM)

    NASA Technical Reports Server (NTRS)

    Fried, Glenn; Grosser, Benjamin

    2004-01-01

    The Imaging Technology Group (ITG) proposed to develop a Virtual SEM (VSEM) application and supporting materials as the first installed instrument in NASA s Virtual Laboratory Project. The instrument was to be a simulator modeled after an existing SEM, and was to mimic that real instrument as closely as possible. Virtual samples would be developed and provided along with the instrument, which would be written in Java.

  15. Implementation of a virtual correlative light and transmission electron microscope.

    PubMed

    Voigt, Tilman; Zuber, Benoît; Gawatz, Gerlinde; Herrmann, Gudrun

    2013-07-01

    In the long run, the widespread use of slide scanners by pathologists requires an adaptation of teaching methods in histology and cytology in order to target these new possibilities of image processing and presentation via the internet. Accordingly, we were looking for a tool with the possibility to teach microscopic anatomy, histology, and cytology of tissue samples which would be able to combine image data from light and electron microscopes independently of microscope suppliers. With the example of a section through the villus of jejunum, we describe here how to process image data from light and electron microscopes in order to get one image-stack which allows a correlation of structures from the microscopic anatomic to the cytological level. With commercially available image-presentation software that we adapted to our needs, we present here a platform which allows for the presentation of this new but also of older material independently of microscope suppliers. PMID:23564491

  16. Enhancing Learning Objectives by Use of Simple Virtual Microscopic Slides in Cellular Physiology and Histology: Impact and Attitudes

    ERIC Educational Resources Information Center

    Anyanwu, Godson Emeka; Agu, Augustine Uchechukwu; Anyaehie, Ugochukwu Bond

    2012-01-01

    The impact and perception of students on the use of a simple, low technology-driven version of a virtual microscope in teaching and assessments in cellular physiology and histology were studied. Its impact on the time and resources of the faculty were also assessed. Simple virtual slides and conventional microscopes were used to conduct the same…

  17. Sedimentary petrology

    SciTech Connect

    Blatt, H.

    1982-01-01

    This is an introductory book to sedimentary petrology and covers the origin, occurrence, mineral composition and texture of sedimentary rocks. The description and interpretation of sedimentary structures, environments and facies are briefly discussed. Chapters cover: the occurrence of sedimentary rocks, formation of sediment, mudrock, conglomerates and sandstones, limestones dolomites, evaporites, cherts, iron-rich, rocks, phosphorites, coal, development of research project and the practice of sedimentary petrology. One chapter has been abstracted separately.

  18. Beagle I and II Voyages: Charles Darwin's rocks and the quest for Mars rock; the Open University's virtual microscope has both

    NASA Astrophysics Data System (ADS)

    Schwenzer, S. P.; Tindle, A. G.; Anand, M.; Gibson, E. K.; Pearson, V. K.; Pemberton, D.; Pillinger, C.; Smith, C. L.; Whalley, P.; Kelley, S. P.

    2011-12-01

    Exploration is in itself a fascinating subject, and a strong draw to engaging the public in understanding science. Nearly two hundred years ago Charles Darwin took part in an exploration of the Earth, and more recently we have begun to explore the solar system and in particular the surface of Mars. The engagement is made easier if an element of exploration is involved in the public engagement, using modern internet and even mobile technologies. The Open University combines all those aspects in a series of virtual microscopes for Earth science that are freely available on the web, installed in museums, or built into its teaching material. The basis of the virtual microscope is a mosaic of several hundred microscopic images of each thin section taken in plane polarised light, between crossed polars and in reflected light, which are then assembled into three high resolution images. Rotation movies for selected points in the thin section illustrate changing optical properties such as birefringence. The user is able to pan and zoom around to explore the section, studying the mineralogy and rock texture, and view the rotation movies linked to points in the section to see the changing birefringence colours. We have created several collections of terrestrial rocks, mainly for teaching purposes, and outreach directly linked to exploration: Charles Darwin returned from the Voyage of the Beagle with a large variety of rock samples, and although thin sections were not being made at that time, they were created from his rocks in the late 19th century. The historic material is part of the "Darwin the Geologist" exhibition at the Sedgwick Museum in Cambridge. Our Darwin virtual microscope includes hand specimen illustrations and thin sections together with documentation and an interactive map allow internet users and museum visitors alike to have a close look at Darwin's rocks and study the petrology of them. Charles Darwin explored distant horizons on Earth in the 19th century; in the 20th century the Apollo astronauts set foot on the Moon, returning valuable rock samples to Earth. Through collaboration between NASA and the OU it became possible to show lunar samples as virtual thin sections. The Beagle II mission represented a new voyage, following Charles Darwin's footsteps, to horizons well beyond the Earth - on a journey to investigate the planet Mars. Although no samples have yet been returned from the red planet, we do have access to Martian meteorites. Like Moon rock samples, these meteorites are rare and very valuable. So, one way to make them accessible to the general public is via the internet using our virtual microscope technology. Within the framework of the EUROPLANET project, and in collaboration with the Natural History Museum in London we are making such meteorites freely available to all. We plan to extend this collection and make it openly accessible for teaching and outreach activities anywhere and any time. Our current microscopes are located at http://microscope.open.ac.uk.

  19. Petrology Home

    NSDL National Science Digital Library

    This site is a clearinghouse for a variety of educational and supporting materials for teaching igneous and metamorphic petrology. Some features of the site are a collection of classroom and laboratory activities, teaching materials such as lecture notes and Power Point presentations, a database of geochemical instruments available for use at various institutions, a collection of petrology syllabi, and email list discussion groups. These collections reflect the contributions of faculty members from across the country, and will continue to grow as new materials and tools are developed.

  20. UNIT, PETROLOGY.

    ERIC Educational Resources Information Center

    Louisiana Arts and Science Center, Baton Rouge.

    THIS TEACHER'S GUIDE FOR A UNIT ON PETROLOGY IS SUITABLE FOR ADAPTATION AT EITHER THE UPPER ELEMENTARY OR THE JUNIOR HIGH SCHOOL LEVELS. THE UNIT BEGINS WITH A STORY THAT INTRODUCES VOLCANIC ACTION AND IGNEOUS ROCK FORMATION. SELECTED CONCEPTS ARE LISTED FOLLOWED BY SUGGESTED ACTIVITIES. A BIBLIOGRAPHY, FILM LIST, VOCABULARY LIST, AND QUESTION AND…

  1. Enhancing learning objectives by use of simple virtual microscopic slides in cellular physiology and histology: impact and attitudes

    NSDL National Science Digital Library

    Augustine Uchechukwu Agu (University of Nigeria)

    2012-06-01

    The impact and perception of students on the use of a simple, low technology-driven version of a virtual microscope in teaching and assessments in cellular physiology and histology were studied. Its impact on the time and resources of the faculty were also assessed. Simple virtual slides and conventional microscopes were used to conduct the same examinations for the same students. Students performed significantly better in the examination with the virtual slide and also showed a significantly higher preference for virtual slides. The time and cost implications of conducting examinations using the simple virtual slides were reduced by >1,400%. The results reemphasize the need for the design and adoption of simple sustainable technological innovations in developing countries to bridge gaps in purposeful learning environments.

  2. Design and Assessment of an Interactive Digital Tutorial for Undergraduate-Level Sandstone Petrology

    NSDL National Science Digital Library

    K. Milliken

    2003-09-01

    This study describes the goals, features and effectiveness of a digital interactive tutorial which was created to provide undergraduates a 'virtual microscope' resource for learning sandstone petrology. The goal of the tutorial is to provide students exposure to the highly visual subject matter of petrography outside the confines of organized laboratory exercises. The hope is that widespread use of such digital interactive formats will allow students to gain high levels of expertise with description and interpretation of earth materials despite the reduced amounts of hands-on laboratory practice that are allowed by modern curricula.

  3. A quadratic programming approach for the mosaicing of virtual slides that incorporates the positioning accuracy of the microscope stage.

    PubMed

    Steckhan, Dirk; Paulus, Dietrich

    2010-01-01

    We describe a novel approach for creating virtual slides that incorporates the positioning accuracy of the microscope stage in the optimization step. To capture a complete slide in microscopy, a large number of fields of view have to be acquired by moving the microscope stage in a controlled way. These fields of view are aligned in such a way that a globally consistent virtual slide is formed. However, depending on the positioning repeatability of the stage and the accuracy of the stage calibration, this results in alignment errors. These errors are usually resolved by applying a mosaicing algorithm. Our algorithm extends known mosaicing approaches by analyzing the positioning accuracy of the stage and incorporating this knowledge to make the mosaicing process more robust. PMID:21095884

  4. The nanomanipulator: a virtual-reality interface for a scanning tunneling microscope

    Microsoft Academic Search

    Russell M. Taylor II; Warren Robinett; Vernon L. Chi; Frederick P. Brooks Jr.; William V. Wright; R. Stanley Williams; Erik J. Snyder

    1993-01-01

    We present an atomic-scale teleoperation system that uses a head-mounted display and force-feedback manipulator arm for a user interface and a Scanning Tunneling Microscope (STM) as a sensor and effector. The system approximates presence at the atomic scale, placing the scientist on the surface, in control, while the experiment is happening. A scientist using the Nanomanipulator can view incoming STM

  5. The Beginnings of Experimental Petrology

    ERIC Educational Resources Information Center

    Eugster, Hans P.

    1971-01-01

    An account of Van't Hoff's change from theoretical chemistry to petrology provides data on the European intellectual climate of the early 1900's and shows how his work laid the foundation for experimental petrology of hard rocks." (AL)

  6. Igneous and Metamorphic Petrology

    Microsoft Academic Search

    James D. Hoover

    1983-01-01

    So many new and exciting topics in petrology have appeared over the last several years that it has become difficult to find a text that deals adequately with fundamentals as well as current topics; the present book may be one of the better texts in its field today because it achieves this combination with clarity and appropriate emphasis. The book

  7. Irreversible thermodynamics in petrology

    SciTech Connect

    Fisher, G.W.; Lasaga, A.C.

    1981-01-01

    The formulation of reaction rates and transport rates from the point of view of entropy production can help elucidate petrologic processes. The theory of irreversible thermodynamics relates fluxes of heat or mass linearly to thermodynamic forces (temperature gradients or chemical potential gradients) near equilibrium. A consequence of the general theory of irreversible thermodynamics is that each flux may be influenced by any of the thermodynamic forces. This type of coupling leads to such effects as thermal diffusion, the Soret effect, and uphill diffusion. The theory, however, constrains the number and size of the coupling phenomenological coefficients. Estimates of the coupling phenomenological coefficients enable a calculation of the importance of these coupling effects. The linear theory of irreversible thermodynamics relates the rates of reactions to the free energy difference of the reaction. This relation can be used along with experimental data to obtain the individual rates of reactions in petrology. The behavior of systems far from equilibrium is shown to be different from that near equilibrium. In particular, the formation of spatial patterns so common in petrology, is intimately related to the action of a system, when far from equilibrium. The analysis of Liesegang type models as well as the spatial patterns arising from autocatalytic effects can provide useful insights into the formation of differentiated layering in petrology. (JMT)

  8. Petrology of Anomalous Eucrites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Peng, Z. X.; Ross, D. K.

    2015-01-01

    Most mafic achondrites can be broadly categorized as being "eucritic", that is, they are composed of a ferroan low-Ca clinopyroxene, high-Ca plagioclase and a silica phase. They are petrologically distinct from angritic basalts, which are composed of high-Ca, Al-Ti-rich clinopyroxene, Carich olivine, nearly pure anorthite and kirschsteinite, or from what might be called brachinitic basalts, which are composed of ferroan orthopyroxene and high-Ca clinopyroxene, intermediate-Ca plagioclase and ferroan olivine. Because of their similar mineralogy and composition, eucrite-like mafic achondrites formed on compositionally similar asteroids under similar conditions of temperature, pressure and oxygen fugacity. Some of them have distinctive isotopic compositions and petrologic characteristics that demonstrate formation on asteroids different from the parent of the HED clan (e.g., Ibitira, Northwest Africa (NWA) 011). Others show smaller oxygen isotopic distinctions but are otherwise petrologically and compositionally indistinguishable from basaltic eucrites (e.g., Pasamonte, Pecora Escarpment (PCA) 91007). The degree of uniformity in delta O-17 of eucrites and diogenites is one piece of evidence considered to favor of a magma-ocean scenario for their petrogenesis. Given that the O isotopic differences separating Pasamonte and PCA 91007 from other eucrites are small, and that there is an absence of other distinguishing characteristics, a legitimate question is: Did the HED parent asteroid fail to homogenize via a magma-ocean stage, thus explaining outliers like Pasamonte? We are initiating a program of study of anomalous eucrite-like achondrites as one part of our effort to seek a resolution of this issue. Here we present preliminary petrologic information on Asuka (A-) 881394, Elephant Moraine (EET) 87520 and EET 87542. We will have studied several more by conference time.

  9. Virtualities.

    ERIC Educational Resources Information Center

    Allen, Brockenbrough S.

    1991-01-01

    Describes virtual realities as environments in which visual, aural, or other stimuli generate in the mind of the user a sense of navigable, frameless, three-dimensional space, and predicts that the availability of computer technology to create real-time, three-dimensional graphics will bring radical changes in the educational use of visualization…

  10. Mineralogy and Petrology Grant

    NASA Astrophysics Data System (ADS)

    The Mineralogical Society of America (MSA) is now accepting applications for its third biennial grant for research in mineralogy and petrology, which will be awarded in 1985. The grant is for $1500: There are no restrictions on how the money is to be spent, as long as it is used in the support of research.The only restriction on eligibility is that the grantee must be between 20 and 30 years of age.The winner will be chosen by the MSA council next fall, based on the recommendation of a committee appointed by the society's president.

  11. Caltech: Experimental Petrology

    NSDL National Science Digital Library

    This Caltech website discusses the work of the Ed Stolper, Peter Wyllie, George Rossman, and Paul Asimow groups in the Geological and Planetary Sciences Department. Under Paul Asimow's link, educators and students can find tutorials and applets dealing with phase equilibria. Edward Stolper provides illustrations and descriptions of his current research which includes experimental and theoretical studies of mantle melting and analyses of oxygen isotope ratios of ocean island volcanoes. George Rossman offers information on his many mineralogy research projects. The website features links to the Hawaii Scientific Drilling Project, the Experimental Petrology Facilities, and the Mineral Spectroscopy Homepage. Researchers can find lists of publications and information on conferences.

  12. Europa's petrological thermal history

    NASA Technical Reports Server (NTRS)

    Ransford, G. A.; Finnerty, A. A.; Collerson, K. D.

    1981-01-01

    A path of geophysical development which takes into account the petrological sequence is presented to describe the thermal evolution of Europa. On the basis of considerations of the likely temperature-pressure conditions in the Europa zone of the circumjovian nebula during the condensation of the satellite on the one hand and of the early thermal evolution on the other, it is argued that most of the water of Europa can be in the form of hydrated silicates in a thick convective boundary layer or throughout the body of the satellite. Such silicates would include the minerals chlorite and/or serpentine, and brucite, and could be maintained in hydrated states by solid state convection within the body. The model predicts that the ice layer on the surface of Europa is considerably thinner than the 150 km that had been estimated before the Voyager mission.

  13. Petrology of metamorphic rocks

    SciTech Connect

    Suk, M.

    1983-01-01

    ''Petrology of Metamorphic Rocks'' reviews Central European opinions about the origin and formation of metamorphic rocks and their genetic systems, confronting the works of such distinguished European scientists as Rosenbusch, Becke, Niggli, Sander, Eskola, Barth and others with present-day knowledge and the results of Soviet and American investigations. The initial chapters discuss the processes that give rise to metamorphic rocks, and the main differences between regional metamorphism and other types of alterations, the emphasis being laid on the material characteristic of the processes of metamorphism, metasomatism and ultrametamorphism. Further chapters give a brief characterization of research methods, together with a detailed genetic classification based on the division of primary rocks into igneous rocks, sediments and ore materials. The effects of metamorphic alterations and those of the properties of the primary rocks are analyzed on the basis of examples taken chiefly from the Bohemian Massif, the West Carpathians, other parts of the European Variscides, from the crystalline Scandinavian Shelf in Norway and Finland, and from the Alps. Typical examples are documented by a number of charts, photographs and petrographical - particularly petrochemical - data.

  14. Microscope 16 THE MICROSCOPE

    E-print Network

    Koptur, Suzanne

    Microscope 16 THE MICROSCOPE In this exercise you will learn about the principles of optical microscopy and become fa- miliar with the use of the microscope. Microscopes are delicate and expensive instruments; they should be handled with utmost care! Before you use the microscope, your instructor

  15. Igneous and Metamorphic Petrology

    NASA Astrophysics Data System (ADS)

    Hoover, James D.

    So many new and exciting topics in petrology have appeared over the last several years that it has become difficult to find a text that deals adequately with fundamentals as well as current topics; the present book may be one of the better texts in its field today because it achieves this combination with clarity and appropriate emphasis. The book provides a comprehensive coverage of descriptive, theoretical, and experimental topics. The relationship between the origin and evolution of igneous and metamorphic rocks and the associated physical and tectonic processes is the unifying theme of the text.The book is intended as a text for undergraduate geology majors with a background in physical and historical geology and mineralogy. It is divided into four main categories: magmatic rock bodies, magmatic systems, metamorphic bodies and systems, and the early history of the earth and other planetary bodies. The organization of the first three of these sections is intended to be flexible in scope, emphasis, and variety of subject matter. Each chapter is outlined, prefaced with an overview of the section, and summarized in outline form. Key terms appear in bold type, and study questions are provided in interpretive chapters. Breadth and clarity of subject matter is emphasized, and good use is made of figures, tables, and photographs of rocks in the field, in hand specimen, and in thin section. The appendix contains a summary of some petrographic techniques, a review of the physical and optical properties of some rock-forming minerals, and representative chemical analyses of some major rock types.

  16. Semantically Enabling Knowledge Representation of Metamorphic Petrology Data

    NASA Astrophysics Data System (ADS)

    West, P.; Fox, P. A.; Spear, F. S.; Adali, S.; Nguyen, C.; Hallett, B. W.; Horkley, L. K.

    2012-12-01

    More and more metamorphic petrology data is being collected around the world, and is now being organized together into different virtual data portals by means of virtual organizations. For example, there is the virtual data portal Petrological Database (PetDB, http://www.petdb.org) of the Ocean Floor that is organizing scientific information about geochemical data of ocean floor igneous and metamorphic rocks; and also The Metamorphic Petrology Database (MetPetDB, http://metpetdb.rpi.edu) that is being created by a global community of metamorphic petrologists in collaboration with software engineers and data managers at Rensselaer Polytechnic Institute. The current focus is to provide the ability for scientists and researchers to register their data and search the databases for information regarding sample collections. What we present here is the next step in evolution of the MetPetDB portal, utilizing semantically enabled features such as discovery, data casting, faceted search, knowledge representation, and linked data as well as organizing information about the community and collaboration within the virtual community itself. We take the information that is currently represented in a relational database and make it available through web services, SPARQL endpoints, semantic and triple-stores where inferencing is enabled. We will be leveraging research that has taken place in virtual observatories, such as the Virtual Solar Terrestrial Observatory (VSTO) and the Biological and Chemical Oceanography Data Management Office (BCO-DMO); vocabulary work done in various communities such as Observations and Measurements (ISO 19156), FOAF (Friend of a Friend), Bibo (Bibliography Ontology), and domain specific ontologies; enabling provenance traces of samples and subsamples using the different provenance ontologies; and providing the much needed linking of data from the various research organizations into a common, collaborative virtual observatory. In addition to better representing and presenting the actual data, we also look to organize and represent the knowledge information and expertise behind the data. Domain experts hold a lot of knowledge in their minds, in their presentations and publications, and elsewhere. Not only is this a technical issue, this is also a social issue in that we need to be able to encourage the domain experts to share their knowledge in a way that can be searched and queried over. With this additional focus in MetPetDB the site can be used more efficiently by other domain experts, but can also be utilized by non-specialists as well in order to educate people of the importance of the work being done as well as enable future domain experts.

  17. Soil Under the Microscope Mini-Workshop

    NSDL National Science Digital Library

    Steven Driese

    This mini-workshop is a brief introduction to the use of the polarized light microscope for thin-section analysis of soils, known as micromorphology. It assumes only a rudimentary knowledge of mineralogy and sedimentary petrology. Participants have an opportunity to describe and characterize soils with different properties in thin section. Applications to environmental geology and hydrogeology are also mentioned.

  18. Theoretical petrology. [of igneous and metamorphic rocks

    NASA Technical Reports Server (NTRS)

    Stolper, E.

    1979-01-01

    In the present paper, some areas of growing interest in the American efforts in petrology during the 1975-1978 quadrennium are reviewed. In igneous petrology, studies of structures and thermodynamic properties of silicate melts and of kinetics of igneous processes are in a period of rapid growth. Plate tectonic concepts have had (and will no doubt continue to have) an important influence by focusing interest on specific problems and by providing a framework for the understanding of petrogenesis. An understanding of mantle processes and evolution through the integration of petrological, geophysical, and geochemical constraints has been developed over the past 20 years, and will undoubtedly provide direction for future petrological studies.

  19. Virtual Quarry

    NSDL National Science Digital Library

    This interactive virtual tour for younger students lets them 'drive' a quarry truck and visit a rock quarry to see how the rock is mined, processed and transported, and what the aggregate is used for. The tour includes safety tips for visiting quarries. They can also 'restore' an abandoned quarry by planting virtual grass, reeds, and trees, view movies about quarries, and use a virtual microscope to look at some rock samples. There are also links to lesson plans on the use and restoration of quarries.

  20. Petrology of the igneous rocks

    NASA Technical Reports Server (NTRS)

    Mccallum, I. S.

    1987-01-01

    Papers published during the 1983-1986 period on the petrology and geochemistry of igneous rocks are discussed, with emphasis on tectonic environment. Consideration is given to oceanic rocks, subdivided into divergent margin suites (mid-ocean ridge basalts, ridge-related seamounts, and back-arc basin basalts) and intraplate suites (oceanic island basalts and nonridge seamounts), and to igneous rocks formed at convergent margins (island arc and continental arc suites), subdivided into volcanic associations and plutonic associations. Other rock groups discussed include continental flood basalts, layered mafic intrusions, continental alkalic associations, komatiites, ophiolites, ash-flow tuffs, anorthosites, and mantle xenoliths.

  1. Microscope Simulation

    NSDL National Science Digital Library

    Here you can read and find out about different kinds of microscopes - what you can see in them and how to prepare specimens for a particular microscope. You can also try the four different microscope simulators and watch and compare images taken with phase contrast microscopes, fluorescence microscopes, transmission electron microscopes and scanning tunneling microscopes. Test your knowledge of microscopes by answering the 20 questions in the "Microscope quiz".

  2. Using Data to Teach Igneous Petrology

    NSDL National Science Digital Library

    Pranoti Asher

    In order to make connections between the two disparate segments (lecture and laboratory) of a Petrology course; short exercises using real data accompany each laboratory exercise. Three examples are discussed pertain to granites, basalts, and andesites.

  3. Petrological studies on lunar rock samples

    NASA Technical Reports Server (NTRS)

    Kushiro, I.

    1974-01-01

    Petrological studies were made on Apollo 14, 15, 16, and 17 lunar samples. High-pressure melting experiments were conducted, along with electron microprobe analyses. The composition of the samples is reported.

  4. Petrology of Anomalous Eucrite QUE 94484

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Peng, Z. X.

    2015-01-01

    Most mafic achondrites are broadly "eucritic", being composed of ferroan low-Ca clinopyroxene, high-Ca plagioclase, a silica phase, ilmenite and accessory phases. Their characteristics indicate that eucrite-like basalts formed on asteroids of similar composition under similar petrologic conditions (T, P, fO2). Some eucrite-like basalts have isotopic compositions and petrologic characteristics consistent with formation on different parent asteroids (e.g., Ibitira, NWA 011). Others show small isotopic differences but no distinguishing petrological characteristics (e.g., Caldera, Pasamonte). We have begun a study of anomalous eucrite-like achondrites in an effort to seek resolution to the issues: Did the eucrite parent asteroid fail to homogenize via a magma-ocean stage, thus explaining outliers like Pasamonte? How many parent asteroids are represented by these basalts? Here we present preliminary petrologic information on anomalous basaltic eucrite QUE 94484.

  5. Sedimentary petrology. 2nd edition

    SciTech Connect

    Blatt, H.

    1992-01-01

    The second edition of Sedimentary Petrology is extensively revised and updated; much effort has been expended to strengthen the weaknesses of the earlier edition, and much of this effort has been successful. It consists of sixteen chapters. Following two introductory chapters (occurrence of sedimentary rocks; weathering and soils), eleven chapters cover the various sedimentary rock types. Coverage is allocated in proportion to their relative abundance and relative ease of study -- three chapters on conglomerates and sandstones (textures and structures, composition, and diagenesis); one on mud rocks; three on carbonates (limestone textures, structures, and environments; limestone mineralogy and diagenesis; and dolostones); and one each on evaporites, cherts, iron-rich rocks, and phosphorites. A novel and useful chapter on paleogeothermometry rounds out the discussion of rocks, followed by chapters on The Development of a Research Project'' and common laboratory methods.

  6. APPLICATIONS OF CATHODOLUMINESCENCE OF QUARTZ AND FELDSPAR TO SEDIMENTARY PETROLOGY.

    USGS Publications Warehouse

    Ruppert, Leslie F.

    1987-01-01

    Cathodoluminescence (CL), the emission of visible light during electron bombardment, was first used in sandstone petrology in the mid-1960's. CL techniques are especially useful for determining the origin and source of quartz and feldspar, two of the most common constituents in clastic rocks. CL properties of both minerals are dependent on their temperature of crystallization, duration of cooling, and/or history of deformation. Detrital quartz and feldspar are typically derived from igneous and metamorphic sources and luminesce in the visible range whereas authigenic quartz and feldspar form at low temperatures and do not luminesce. Quantification of luminescent and non-luminescent quartz and feldspar with the scanning electron microscope, electron microprobe, or a commercial CL device can allow for the determination of origin, diagenesis, and source of clastic rocks when used in conjunction with field and other petrographic analyses.

  7. Focusing One's Microscope By Daniel Pauly

    E-print Network

    Pauly, Daniel

    The Lead Focusing One's Microscope By Daniel Pauly Sea Around Us Project, Fisheries Centre discoveries are often a matter of focusing one's microscope -- actual or virtual -- and so rules have emerged's Microscope. The Science Chronicles (The Nature Conservancy), January 2011: 4-7. #12;! Establishing

  8. Petrology and geochemistry of Antarctic micrometeorites

    Microsoft Academic Search

    Gero Kurat; Christian Koeberl; Thomas Presper; Franz Brandstätter; Michel Maurette

    1994-01-01

    The petrology and geochemistry of twentythree chondritic dust particles with masses of 1-47 g (sizes 100-400 m) were recovered from blue ice near Cap Prudhomme, Antarctica, and studied by INAA, ASEM, EMPA, and optical microscopy. Sample selection criteria were irregular shape and (for a subsample) black color, with the aim of studying as many unmelted micrometeorites (MMs) as possible. Of

  9. Microscope Webquest

    NSDL National Science Digital Library

    Mrs. Smith

    2011-02-17

    Work with your table partner to complete this activity about using microscopes. Visit the following links to complete the worksheet given to you. A-Z Microscope History Microbus - History of the Microscope What in the World - National Geographic games Magnification Model Powers of 10 If you finish you may return to the What in the World - National Geographic games ...

  10. Magmas and magmatic rocks: An introduction to igneous petrology

    SciTech Connect

    Middlemost, E.A.K.

    1986-01-01

    This book melds traditional igneous petrology with the emerging science of planetary petrology to provide an account of current ideas on active magmatic and volcanic processes, drawing examples from all igneous provinces of the world as well as from the moon and planets. It reviews the history and development of concepts fundamental to modern igneous petrology and includes indepth sections on magmas, magnetic differentiation and volcanology.

  11. Virtual Lab Educational Software

    NSDL National Science Digital Library

    Hogan, Patrick

    NASA Learning Technologies (NLT) is a NASA R&D effort for the engineering of teaching tools that deliver NASA content in the most engaging and dynamic manner possible. NLT builds the pipeline and the delivery point for unencumbered access to the best data NASA has to provide. Virtual Lab completely emulates a scanning electron microscope and allows any user to zoom and focus into a variety of built-in microscopic samples. It also comes with a set of educational materials such as a demo on how a SEM works and movies of the real thing in action. Virtual Lab is freely available with a growing library of samples to choose from.

  12. Petrologic Locations of Nanodiamonds in Carbonaceous Chondrite Meteorites

    NASA Astrophysics Data System (ADS)

    Garvie, Laurence

    Nanodiamonds (NDs), with dimensions near two nanometers, are widespread accessory minerals in primitive meteorites. They have been studied extensively in concentrates made from acid-insoluble residues, but surprisingly little is known about their petrologic settings in the meteorites because they have not been studied in situ. Information about such settings is fundamental for determining how they formed and were incorporated into the meteorites. The primary goal of the planned research is to determine and compare the petrologic settings of NDs within matrix of different types of carbonaceous chondrites, with the long-term aim of providing new insights regarding the origin of NDs. This research will also provide new data on the structure and major and trace element compositions of individual NDs and regions within them. Transmission electron microscopes (TEMs) provide uniquely powerful information regarding chemical, bonding, and structural data on the scale needed to solve this problem, assuming the NDs can be located within the host matrix. We have developed methods of observing NDs in situ within the fine-grained matrix of primitive meteorites and will use various TEMs to accomplish that goal for several meteorites. High- resolution imaging and electron energy-loss spectroscopy (EELS) will permit determination of both structural and chemical information about the NDs and their adjacent minerals. By the middle of the proposed grant period, two state-of-the-art, aberration-corrected TEMs will have been installed at ASU and will be used to locate heavy elements such as Xe, Te, and Pd within the NDs. These TEMs permit the imaging of individual atoms of heavy elements with annular dark-field (ADF) imaging, and these atoms can be identified using EELS. The result of these new types of measurements will provide information about whether such elements, which have been used to determine whether NDs formed in supernovae, occur within the interiors or on the surfaces of the NDs. The proposed research will contribute to the NASA vision statement and goal to "Advance scientific knowledge of the origin and history of the solar system ..." (NASA's Strategic Goals, ROSES Table 1A, Strategic Sub-goal 3C) and "Discover the origin, structure, evolution, and destiny of the universe, and search for Earth-like planets" (NASA's Strategic Goals, ROSES Table 1A, Strategic Sub-goal 3D). The proposed research will generate fundamental new knowledge regarding meteoritic NDs and an improved understanding of primitive materials.

  13. Rethinking how Undergraduate ``Hard Rock'' Petrology is Taught

    NASA Astrophysics Data System (ADS)

    Reid, M. R.

    2010-12-01

    A course in "hard rock" petrology forms a core component of undergraduate training in the geosciences. In most cases, the subjects of igneous and metamorphic petrology are combined in a single course and the course is traditionally structured so that the two subjects are covered in series. This approach enables students to focus on each subject separately, with knowledge of igneous rocks helping students to understand metamorphic rock protoliths. Student assessment shows, however, that this approach tends to compartmentalize learning and the two main subjects might just as well be taught in separate courses. In practical applications such as fieldwork, students must be able to access their understanding of igneous and metamorphic rocks virtually simultaneously. To better integrate student learning, I developed a spiral learning approach to teaching petrology (e.g., Bruner, 1990; Dyar et al., 2004) so that commonalities could be revisited several times over the course of a semester and, in so doing, students' grasp of the fundamental insights provided by igneous and metamorphic rocks could be scaffolded into greater understanding. The course initially focuses on the dynamics of the environments in which igneous and metamorphic rocks form: heat flow, fluid flow, and plate tectonics. Several subsequent weeks explore topics relevant to identifying and understanding igneous and metamorphic rocks in the field: crystal nucleation and growth, the roles of pressure and heat, and field classification. Laboratory exercises parallel this structure, also emphasizing observations that are valuable in the field: the relationship between minerals and rocks, textural observations, and general rock classification. The final portion of the course explores “hard rocks” in more detail with a greater emphasis on the interplay between chemistry and mineralogy. A variety of learner-centered activities in the course help students bridge the gap between novice and expert and include more explicit emphasis on visualization and on helping students become comfortable with interpreting data numerically and graphically. Pen tablet computers are used extensively in the laboratory for visualization, photomicrograph capture, and annotation. Cooperative learning activities developed for this course make use of learning methods such as pair share, round-robin, small group explorations case studies, and jigsaw exercises (sometimes as introduction to, sometimes as review of material), and Jeopardy-style review sessions. On an assessment questionnaire at the end of the semester students ranked the in-class cooperative learning activities as on par with lectures and homework exercises in facilitating their learning. Students reported satisfactory attainment of three major goals identified for the course even though they were not explicitly reminded of these goals at the time of assessment. References cited: Bruner, J., 1990. Acts of Meaning. Harvard University Press.; Dyar, M.D., Gunter, M.E., Davis, J.C., and Odell, M.R., 2004. Integration of new methods into teaching mineralogy; Huba, M.E. and Freed, J.E., 2000. Learner-centered Assessment on College Campus: Shifting the Focus from Teaching to Learning. Allyn and Bacon.

  14. Petrology of Apollo 11 regolith breccias

    NASA Technical Reports Server (NTRS)

    Simon, S. B.; Papike, J. J.; Shearer, C. K.

    1984-01-01

    Petrographic and mineral chemical data for 16 Apollo 11 regolith breccias show that: (1) the regolith breccias differ from soil 10084 with respect to agglutinate content, glass population, plagioclase compositions, and proportions of high-K mare and low-K mare basalt components; (2) the A-11 breccias and soil have highland components that are similar both in abundance and petrology; and (3) lunar regolith breccias provide a better comparison with howardites than do lunar soils. The data and observations are consistent with formation of the regolith breccias from immature soil. It appears that little or no highland material has been added to the Tranquillitatis regolith since the formation of the breccias.

  15. Using Dynamic Digital Maps to Teach Petrology

    NSDL National Science Digital Library

    Christopher D. Condit

    In this session we will examine how to utilize Dynamic Digital Maps (DDMs) in undergraduate petrology courses to bring inaccessible and exciting volcanic field areas to the students in the classroom and to engage the students in authentic research experiences. A DDM is a stand-alone "presentation manager" computer program that contains interactive maps, analytical data, digital images and movies. They are essentially complete geologic maps in digital format, available on CD-ROM and on line. We have developed two different kinds of exercises that use DDMs to provide field-based context for undergraduate research projects in petrology. In one, the students use the DDM of the Tatara-San Pedro volcanic complex of the Andes Mountains of central Chile to develop a group research poster on part of the volcano's evolution, to present to the class, modeled after what would be presented at a national meeting. The second exercise focuses on the Springville Volcanic field, where the students try to understand the magma evolution using both field relations and quantitative modeling skills. Read a complete description of how dynamic digital maps work, with more ideas for the classroom. (from Teaching with Data, Simulations and Models)

  16. In vivo virtual intraoperative surgical photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Han, Seunghoon; Lee, Changho; Kim, Sehui; Jeon, Mansik; Kim, Jeehyun; Kim, Chulhong

    2013-11-01

    We developed a virtual intraoperative surgical photoacoustic microscopy system by combining with a commercial surgical microscope and photoacoustic microscope (PAM). By sharing the common optical path in the microscope and PAM system, we could acquire the PAM and microscope images simultaneously. Moreover, by employing a beam projector to back-project 2D PAM images onto the microscope view plane as augmented reality, the conventional microscopic and 2D cross-sectional PAM images are concurrently mapped on the plane via an ocular lens of the microscope in real-time. Further, we guided needle insertion into phantom ex vivo and mice skins in vivo.

  17. In vivo virtual intraoperative surgical photoacoustic microscopy

    SciTech Connect

    Han, Seunghoon, E-mail: hsh860504@gmail.com; Kim, Sehui, E-mail: sehui0916@nate.com; Kim, Jeehyun, E-mail: jeehk@knu.ac.kr, E-mail: chulhong@postech.edu [School of Electrical Engineering and Computer Science, Kyungpook National University, Daegu 702-701 (Korea, Republic of)] [School of Electrical Engineering and Computer Science, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lee, Changho, E-mail: ch31037@postech.edu; Jeon, Mansik, E-mail: msjeon@postech.edu [Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of)] [Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of); Kim, Chulhong, E-mail: jeehk@knu.ac.kr, E-mail: chulhong@postech.edu [Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of) [Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of); Department of Biomedical Engineering, The State University of New York at Buffalo, Buffalo, New York 14221 (United States)

    2013-11-11

    We developed a virtual intraoperative surgical photoacoustic microscopy system by combining with a commercial surgical microscope and photoacoustic microscope (PAM). By sharing the common optical path in the microscope and PAM system, we could acquire the PAM and microscope images simultaneously. Moreover, by employing a beam projector to back-project 2D PAM images onto the microscope view plane as augmented reality, the conventional microscopic and 2D cross-sectional PAM images are concurrently mapped on the plane via an ocular lens of the microscope in real-time. Further, we guided needle insertion into phantom ex vivo and mice skins in vivo.

  18. Martian Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

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

  19. Microscopic colitis.

    PubMed

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

    2004-08-01

    Microscopic colitis is an idiopathic chronic inflammatory bowel disease presenting with watery diarrhea. While colonoscopy and radiology findings are normal, the colon shows striking pathologic findings, including lymphocytic colitis and collagenous colitis. The clinical course is usually benign with sustained remission. Recent medical evidence shows that bismuth and budesonide are effective treatments. PMID:15326829

  20. Microscopic colitis

    PubMed Central

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

    2012-01-01

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

  1. Petrological and rheological controls on volcanism to terrestrial planets

    E-print Network

    Elkins Tanton, Linda Tarbox, 1965-

    2002-01-01

    Through experimental petrology and geodynamic modeling, processes of melting under thick lithospheres on the Earth and the moon are investigated. Phase equilibrium experiments were carried out on Apollo 14B and 15C picritic ...

  2. A geochemical, petrological, and geophysical case study of Caryn Seamount 

    E-print Network

    Drew, Fred Prescott

    1975-01-01

    ) December 1975 ABSTRACT A Geochemical, Petrological, and a Geophysical Case Study of Caryn Seamount (December 1975) Fred P. Drew, B. A. Colgate University Chairman of Advisory Committee: Robert B. Scott The principal objective of this research...

  3. Meteorites: A Petrologic, Chemical and Isotopic Synthesis

    NASA Astrophysics Data System (ADS)

    Jones, Rhian

    2005-11-01

    Meteorites, through their astonishingly diverse record of exotic geological environments that chronicle the formation of the solar system, provide us with a material connection to our fundamental origins. They inform us about processes including condensation of stardust in stellar outflows, formation of the solar nebula cloud, interactions between water and minerals on asteroids, planetary core formation, and igneous as well as surface processes on Mars and the Moon. Meteorites: A Petrologic, Chemical and Isotopic Synthesis is a book that invites one to explore the wonders of our solar system and beyond. This book, written by Robert Hutchison, is loosely modeled as an update of the classic volume by Dodd [1981]. In the intervening 24 years, meteoritics has undergone a fast-paced revolution, resulting from the recovery of thousands of new samples from Antarctica and the hot deserts, combined with dramatic progress in analytical techniques.

  4. Petrology of brecciated ferroan noritic anorthosite 67215

    NASA Technical Reports Server (NTRS)

    Mcgee, James J.

    1988-01-01

    A petrologic study of breccia 67215 is presented, showing that the rock has the bulk composition of a ferroan noritic anorthosite and is a polymict breccia containing several lithic clast types within a crushed, cataclastic matrix. The dominant lithic clasts contained in breccia 67215 are found to be igneous and metamorphic low- and high- Ca pyroxenes and olivine. Other clasts include granulated and sheared clasts, coarse-grained anorthosite with relatively Fe-rich augite, aphanitic, feldspathic microporphyritic melt breccias, and an impact-melt rock with strongly zoned relatively Mg-rich pyroxene. It is concluded that this rock type is relatively common in the highlands regolith excavated by the North Ray Crater.

  5. Petrology and Composition of HED Polymict Breccias

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Herrin, J. S.; Mertzman, S. A.; Mertzman, K. R.

    2010-01-01

    The howardite, eucrite and diogenite (HED) clan of meteorites forms the largest suite of achondrites with over 900 named members. The HEDs are igneous rocks and breccias of igneous rocks from a differentiated asteroid [1]. The consensus view is that these rocks hail from the asteroid 4 Vesta, which will be the first target of NASA's Dawn mission. When Dawn arrives at Vesta, she will begin remote imagery and spectroscopy of the surface. The surface she will observe will be dominated by rocks and soils mixed through impact gardening. To help with the interpretation of the remotely sensed data, we have begun a project on the petrologic and compositional study of a suite of HED polymict breccias. Here we report on the preliminary findings of this project.

  6. Petrology, Geochemistry and Genesis of Ureilites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Hudon, Pierre; Galindo, Charles, Jr.

    2005-01-01

    Ureilites are enigmatic achondrites that have some characteristics resulting from high temperature igneous processing, yet retain other characteristics inherited from the solar nebula. They are basalt-depleted ultramafic rocks containing 7-66 mg/g elemental C. They are rich in noble gases and display a correlation between mg# and Delta (17)O. This mishmash of properties has engendered various models for ureilite genesis, from those in which nebular processes dominate to those in which parent body igneous processes dominate. Characterization of new ureilites, especially of new subtypes, is an important part of attempts to unravel the history of the ureilite parent body or bodies. Here we report on the petrology and geochemistry of a suite of ureilites, mostly from Antarctica, and use these data to discuss ureilite petrogenesis. Additional information is included in the original extended abstract.

  7. Lunar composition - A geophysical and petrological synthesis

    NASA Astrophysics Data System (ADS)

    Mueller, S.; Taylor, G. J.; Phillips, R. J.

    1988-06-01

    Lunar compositional constraints are derived on the basis of geophysical data (in particular, the lunar seismic model as revised by Nakamura) and petrological arguments. Only in the case of extreme assumptions can critical aspects of bulk lunar composition be demonstrated to be equivalent to the present-day terrestrial mantle; specifically, the moon has an Mg number that is too low and an alumina abundance that is too high. Over a broad range of crustal densities the presence of a metallic core at least 150 km in radius is necessary to reconcile the upper mantle lunar seismic model with mass and moment of inertia constraints. A significant seismic discontinuity at 500 km depth may mark the lowest extent of early lunar differentiation, possibly representing a transition between highly fractionated upper mantle and less fractionated, perhaps even primordial, middle/lower mantle.

  8. Computation lithography: virtual reality and virtual virtuality.

    PubMed

    Lam, Edmund Y; Wong, Alfred K

    2009-07-20

    Computation lithography is enabled by a combination of physical understanding, mathematical abstraction, and implementation simplification. An application in the virtual world of computation lithography can be a virtual reality or a virtual virtuality depending on its engineering sensibleness and technical feasibility. Examples under consideration include design-for-manufacturability and inverse lithography. PMID:19654627

  9. Altering petrology through microbial dissimilatory phosphite oxidation

    NASA Astrophysics Data System (ADS)

    Zhu, H.; Figueroa, I.; Coates, J. D.

    2013-12-01

    Microbial enhanced oil recovery (MEOR) takes advantage of various microbial metabolisms to increase hydrocarbon and energy yield by improving oil flow and flood water sweep in a reservoir during tertiary recovery. Wormholing at the injection well is believed to be the result of the large drop in pressure when water exits the injection well and enters the unconsolidated reservoir matrix. One possible means of prevent this event is to consolidate the rock matrix immediately around the injection well to create a permeable zone of stable petrology. Many microbial processes are known to result in the precipitation of ionic components into their environment creating solid-phase minerals. Such processes could be judiciously applied to bind unconsolidated matrices in order to form a permeable concreted rock matrix, which would minimize wormholing events and thus improve floodwater sweep. However, to date, apart from the application of urea oxidation creating calcium carbonate precipitation, there has been little investigation of the applicability of these precipitated bioconcretions to MEOR strategies and none to control wormholing events. Here we present a novel approach to altering rock petrology to concrete unconsolidated matrices in the near well environment by the biogenesis of authigenic minerals through microbial dissimilatory phosphite oxidation. Desulfotignum phosphitoxidans, strain FiPS-3 is currently the only isolated organism capable of using phosphite (HPO32-) as an electron donor for growth. This process, known as dissimilatory phosphite oxidation (DPO), can be coupled to either sulfate reduction or homoacetogenesis and leads to the accumulation of inorganic phosphate in the medium. The resulting insoluble mineral phases can coat the rock environment resulting in a concretion binding the unconsolidated matrix particles into a single phase. In this study we demonstrate that DPO can effectively produce calcium or magnesium phosphate minerals in packed glass bead mini-columns and could potentially be applied to create a concretion binding the unconsolidated matrix particles into a single phase.

  10. Using quantitative phase petrology to understand metamorphism

    NASA Astrophysics Data System (ADS)

    White, Richard

    2015-04-01

    Quantitative phase petrology has become one of the mainstay methods for interpreting metamorphic rocks and processes. Its increased utility has been driven by improvements to end-member thermodynamics, activity-composition relationships and computer programs to undertake calculations. Such improvements now allow us to undertake calculations in increasingly complex chemical systems that more closely reflect those of rocks. Recent progress in activity-composition (a-x) relationships is aimed at developing suites of a-x relationships in large chemical systems that are calibrated together, which will allow a more direct application of the method to metamorphic rocks. In addition, considerable progress has been made in how quantitative phase diagrams can be used to understand features, including chemical potential diagrams for reaction textures, methods for fractionating bulk compositions and methods for modelling open system processes. One feature of calculated phase diagrams is that they present us with a great amount of information, such as mineral assemblages, mineral proportions, phase compositions, volume or density etc. An important aspect to using this information is to understand the potential uncertainties associated with these, which are significant. These uncertainties require that calculated phase diagrams be used with caution to interpret observed features in rocks. Features such as mineral zoning and reaction textures should still be interpreted in a semi-quantitative way, even if based on a fully quantitative diagram. Exercises such as the interpretation of reaction overstepping based on relating phase diagrams to observed mineral core compositions are likely to give spurious results given the infelicities in existing a-x models. Despite these limitations, quantitative phase petrology remains the most useful approach to interpreting the metamorphic history of rocks in that it provides a theoretical framework in which to interpret observed features rather than a literal truth

  11. Magnetic petrology of eastern North America diabases. I - Olivine-normative dikes from western South Carolina

    NASA Technical Reports Server (NTRS)

    Warner, Richard D.; Wasilewski, Peter J.

    1990-01-01

    The oxide mineralogy and the magnetic behavior of 15 olivine-normative samples obtained from South-Caroline diabase dikes were investigated using electron microprobe and SEM analyses and measurements of natural remanence magnetization (NRM), saturation isothermal remanence magnetization (SIRM), and anhysteritic remanence magnetization. It was found that chromite (which for these olivine-normative diabases is a sensitive petrologic indicator) constitutes up to 0.5 vol pct and that its abundance and composition correlate with bulk rock Cr. Microscopic analyses showed that titanomagnetite compositions were mostly between 0.4 and 0.55. The values of NRM and the NRM/SIRM ratios varied between 4 and 0.01 A sq m/kg and 0.0019 and 0.032, respectively. These properties inversely correlate with Cr content and demonstrably contrast Cr-rich and Cr-poor samples.

  12. Microscope and method of use

    DOEpatents

    Bongianni, Wayne L. (Los Alamos, NM)

    1984-01-01

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

  13. Microscope and method of use

    DOEpatents

    Bongianni, W.L.

    1984-04-17

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

  14. Microscope and method of use

    SciTech Connect

    Bongianni, W.L.

    1981-08-18

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

  15. Virtual Courseware: Drosophila

    NSDL National Science Digital Library

    In this virtual lab exercise, students can discover and apply principles of genetic inheritance by studying fruit flies (Drosophila) in an interactive online environment. The exercise allows them to order fruit fly mutants from a web merchant, mate the flies in an incubator, anesthetize flies for observation, examine them under a microscope, and analyze the data from offspring to determine patterns of inheritance. Notes and experimental data can be saved online in a virtual notebook and used to generate a report. The exercise concludes with an online quiz, and alignments to state and national standards are included.

  16. PhD position in igneous petrology MarieCurie Initial Training Network ABYSS (ESR2)

    E-print Network

    Demouchy, Sylvie

    PhD position in igneous petrology Marie in igneous petrology and geochemistry. The successful applicant will study rockforming processes, geochemical modelling Goals: Define field relations of crustal rocks and host mantle peridotites

  17. Jens Haeusser likens a virtual ID card to your physical driver's licence with features to protect privacy

    E-print Network

    Farrell, Anthony P.

    scientists study water quality. VIRTUAL LABVIRTUAL BOAT GREEN BUILDING Take a 3-D virtual reality flight, construction and landscaping. Visit a virtual science lab and peek through a microscope to view tiny aquatic

  18. Petrology and radiogeology of the Stripa pluton

    SciTech Connect

    Wollenberg, Harold; Flexser, Steve; Andersson, Lennart

    1980-12-01

    To better define the character of the rock encompassing the thermomechanical and hydrological experiments at the Stripa mine in central Sweden, and to help determine the size of the Stripa pluton, detailed studies were conducted of the petrology and radiogeology of the quartz monzonite and adjacent rocks. Petrologic studies emphasized optical petrography, with supplementary X-ray diffraction, X-ray fluorescence and microprobe analyses. Radiogeologic investigations were based primarily on surface and underground gamma-ray spectrometric measurements of uranium, thorium and potassium, supplemented by laboratory gamma spectrometric analyses and fission-track radiographic determinations of the locations and abundance of uranium in the rock matrix. Both the quartz monzonite and the metavolcanic leptite which it intruded are strongly fractured. Two stages of fracture filling are evident; an earlier stage encompassing quartz, sericite, feldspar, epidote, and chlorite, and a later stage dominated by carbonate minerals. The Stripa quartz monzonite is chemically and mineralogically distinct from other plutons in the region. Muscovite is the predominant mica in the quartz monzonite; biotite has been altered to chlorite, hornblende is absent, and accessory minerals are scarce. In contrast, in other plutons in the Stripa region biotite and hornblende are prominent mafic minerals and accessory minerals are abundant. The Stripa quartz monzonite is also considerably more radioactive than the leptite and other plutons in the region. Uranium and thorium abundances are both- 30 ppm, considerably higher than in "normal" granitic rocks where the thorium-to-uranium ratio generally exceeds 2. Potassium-argon dating of muscovite from the Stripa quartz monzonite indicates that this rock may be older, at 1691 million years than granitic rock of the neighboring Gusselby and Kloten massifs, whose ages, based on K-Ar dating of biotite, are respectively 1604 and 1640 m.y. Heat flow and heat productivity considerations show that although Stripa quartz monzonite contains high abundances of radioelements, the pluton has little effect on the regional heat flow. If it occurs in a layered plutonic setting, it is not more than 1.5 km thick; otherwise it may comprise a stock, dike, or border phase that is relatively small compared with the large granitic plutons exposed in the region.

  19. The lunar regolith - Chemistry, mineralogy, and petrology

    NASA Technical Reports Server (NTRS)

    Papike, J. J.; Simon, S. B.; Laul, J. C.

    1982-01-01

    The data base on the lunar regolith is surveyed to form a synthesis of the lunar regolith chemistry, mineralogy, and petrology. The data were derived from samples collected by the Apollo missions 11-17 and the Luna 16, 20, and 24 probes. The missions were sent to sample formations and areas which typified the common observed features of the lunar surface. Drive tubes were used to extract samples from beneath the surface in order to study the relationship between the regolith and the bedrock, as well as to identify the processes that formed the regolith, which is regarded as the prime source of raw materials for early lunar industrial activities. Regolith origins are now understood to be destructive processes of comminution and constructional processes of agglutinate formation. Mixing occurs on the local scale, although lateral transport is inefficient on the moon. The usual contents of the fraction of regolith less than 10 microns in diameter are Al2O3, CaO, Na2O, K2O, light REE, and Th.

  20. On the Basic Principles of Igneous Petrology

    NASA Astrophysics Data System (ADS)

    Marsh, B. D.

    2014-12-01

    How and why Differentiation occurs has dominated Igneous Petrology since its beginning (~1880) even though many of the problems associated with it have been thoroughly solved. Rediscovery of the proverbial wheel with new techniques impedes progress. As soon as thin section petrography was combined with rock and mineral chemistry, rock diversity, compositional suites, and petrographic provinces all became obvious. The masterful 1902 CIPW norm in a real sense solved the chemical mystery of differentiation: rocks are related by the addition and subtraction of minerals in the anciently appreciated process of fractional crystallization. Yet few believed this, even after phase equilibria arrived. Assimilation, gas transfer, magma mixing, Soret diffusion, immiscibility, and other processes had strong adherents, even though by 1897 Becker conclusively showed the ineffectiveness of molecular diffusion in large-scale processes. The enormity of heat to molecular diffusion (today's Lewis no.) should have been convincing; but few paid attention. Bowen did, and he refined and restated the result; few still paid attention. And in spite of his truly masterful command of experiment and field relations in promoting fractional crystallization, Fenner and others fought him with odd arguments. The beauty of phase equilibria eventually dominated at the expense of knowing the physical side of differentiation. Bowen himself saw and struggled with the connection between physical and chemical processes. Progress has come from new concepts in heat transfer, kinetics, and slurry dynamics. The key approach is understanding the dynamic competition between spatial rates of solidification and all other processes. The lesson is clear: Scholarship and combined field, laboratory and technical expertise are critical to understanding magmatic processes. Magma is a limitlessly enchanting and challenging material wherein physical processes buttressed by chemistry govern.

  1. The petrographic microscope: Evolution of a mineralogical research instrument

    USGS Publications Warehouse

    Kile, D.E.

    2003-01-01

    The petrographic microscope, designed to observe and measure the optical properties of minerals as a means of identifying them, has provided a foundation for mineralogical and petrological research for more than 120 years. Much of what is known today in these fields is attributable to this instrument, the development of which paralleled an evolution of fundamental optical theory and its correlation with mineral structure and composition. This instrument and its related accessories have evolved through a range of models and designs, which are in themselves distinctive for their scientific function and elegant construction, and are today prized by collectors of scientific instruments.

  2. Petrology, Mineralogy, and Genesis of Lunar Crystalline Igneous Rocks

    Microsoft Academic Search

    G. Malcolm Brown

    1970-01-01

    Information on the mineralogy and petrology of the Apollo 11 crystalline basaltic rocks, obtained by about 35 groups of investigators, is summarized and used as a basis for speculation. The textural assemblage indicates near-surface, rapid crystallization from low-viscosity basaltic magmas under low oxygen pressures. The basalts are subsilicic and subalkaline, but only locally, titaniferous. Terrestrial alkali basalts could, through alkali

  3. GEOL 2520 IGNEOUS AND METAMORPHIC PETROLOGY COURSE OUTLINE

    E-print Network

    Chakhmouradian, Anton

    of the Earth's mantle and crust. The origin of igneous and metamorphic rocks. IGNEOUS PETROLOGY The origin of magmas Chapter(s) 1, 6 (selected topics) Mineralogy of igneous rocks Major, minor, and accessory minerals in igneous rocks: a review (major rock-forming minerals are emphasized). Introduction to igneous phase

  4. Mantle petrology and mineralogy of the Thetford Mines Ophiolite Complex

    E-print Network

    Long, Bernard

    Mantle petrology and mineralogy of the Thetford Mines Ophiolite Complex Philippe Pagé a,1 , Jean H ophiolite complex (TMOC) formed by boninite-fed seafloor-spreading, probably in a fore-arc environment: Thetford Mines Ophiolite; Mantle Melting; Mantle Metasomatism; Mineral Chemistry; Southern Québec

  5. Ocean Islands and mantle plumes: Outstanding geochemical and petrological questions

    E-print Network

    Geist, Dennis

    Ocean Islands and mantle plumes: Outstanding geochemical and petrological questions Matt Jackson interior #12;Ocean island lavas provide a window to the mantle s composition Hofmann (Nature, 1997) Unmelt lavas to infer mantle composition Global Hotspot distribution #12;Lavas as probes of the mantle

  6. Mineralogy and Petrology of New Antarctic Nakhlite MIL 03346

    NASA Technical Reports Server (NTRS)

    McKay, G.; Schwandt, C.

    2005-01-01

    Among the approx.1300 meteorites returned from Antarctica by the 2003-2004 ANSMET expedition was a 715g nakhlite, MIL 03346, recovered from the Miller Range. Samples of this meteorite were distributed to investigators on December 16, 2004. We were allocated PTS MIL 03346,63,100. This abstract is our preliminary report on the mineralogy and petrology of this important new sample.

  7. Petrology of a Transform Fault Zone and Adjacent Ridge Segments

    Microsoft Academic Search

    W. G. Melson; G. Thompson

    1971-01-01

    The Vema Fracture Zone in the North Atlantic (9 to 11 degrees N), which has been identified as a transform fault zone, contains exposures of serpentinized peridotites, while its adjacent ridge segments are floored mainly by typical abyssal ocean ridge basalts. This petrologic contrast correlates with the greater frequency of volcanic eruptions along the actively spreading ridge segments compared to

  8. A Simulated Research Problem for Undergraduate Metamorphic Petrology.

    ERIC Educational Resources Information Center

    Amenta, Roddy V.

    1984-01-01

    Presents a laboratory problem in metamorphic petrology designed to simulate a research experience. The problem deals with data on scales ranging from a geologic map to hand specimens to thin sections. Student analysis includes identifying metamorphic index minerals, locating their isograds on the map, and determining the folding sequence. (BC)

  9. Ultrahigh Pressure Metamorphism: Cambridge Topics in Petrology

    NASA Astrophysics Data System (ADS)

    Evans, Bernard W.

    The field of ultra-high pressure metamorphism (UHPM) emerged only 12 years ago when microscopic relics of coesite were found in crustal rocks that had been metamorphosed during subduction related to continental collision. Coesite-bearing metamorphic rocks were soon found elsewhere, and then metamorphic microdiamonds were discovered. Suddenly, the pressure axis for orogenic metamorphism had expanded from 1.5-2.0 to 3.0-4.0 GPa!

  10. Virtual time

    Microsoft Academic Search

    David R. Jefferson

    1985-01-01

    Virtual time is a new paradigm for organizing and synchronizing distributed systems which can be applied to such problems as distributed discrete event simulation and distributed database concurrency control. Virtual time provides a flexible abstraction of real time in much the same way that virtual memory provides an abstraction of real memory. It is implemented using the Time Warp mechanism,

  11. Introduction to the Microscope

    NSDL National Science Digital Library

    Nikon (Nikon Corporation)

    2011-01-01

    The microscope operation procedures and points provided here constitute just one example of how to successfully use a microscope. Depending upon the purpose of the observation, adjustments sometimes differ from the general adjustments that are usually carried out. Users accumulate know-how and experience of the operation of microscopes by first understanding the purpose of an operation and then using the microscope.

  12. Automatic Camera-based Microscope Calibration for a Tele-Micromanipulation System using a

    E-print Network

    Paris-Sud XI, Université de

    1 Automatic Camera-based Microscope Calibration for a Tele-Micromanipulation System using a Virtual a visual calibration technique for an optical microscope coupled to a CCD camera. The accuracy of the workspace is reconstructed through the real-time imaging of two perpendicular optical microscopes. Our

  13. Revista Virtual poca Ecolgica

    E-print Network

    Nacional Autónoma de México, Universidad

    Revista Virtual Época Ecológica REVISTA VIRTUAL ÉPOCA ECOLÓGICA Plan de Conservación de Felinos del). #12;Revista Virtual Época Ecológica REVISTA VIRTUAL ÉPOCA ECOLÓGICA Plan de Conservación de Felinos

  14. Petrologic and Chemical Characterization of a Suite of Antarctic Diogenites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Mertzman, S. A.; Peng, Z. X.; Mertzman, K. R.

    2013-01-01

    The origin of diogenites, ultramafic cumulates related to eucrites, is an unresolved problem [1]. Most diogenites are orthopyroxenites, a few are harzburgites [2], and some are transitional to cumulate eucrites [1, 3]. Cumulate eucrites are gabbros formed by crystal fractionation from basaltic eucrites [4]. The consensus view is that basaltic eucrites are residual melts from global-magma-ocean crystallization on their parent asteroid [4] which is plausibly Vesta [5]. However, the petrologic and compositional characteristics of diogenites seem to preclude a magma ocean origin [1, 4]. We are doing a petrologic and chemical study of new or unusual diogenites with the ultimate goals of constraining their genesis, and the geologic evolution of Vesta.

  15. Petrology and pairing of mesosiderites from Victoria Land, Antarctica

    NASA Technical Reports Server (NTRS)

    Hewins, Roger H.

    1988-01-01

    Petrological data on mesosiderites from Reckling Peak (RKP) and Allan Hills (ALH), Antarctica, are presented. The results suggest that the Allan Hills mesosiderites A77219, A81059, and A81098 are probably paired (being of similar texture, modes, and mineral composition), and ALHA 81208 is, most likely, a clast from one of these mesosiderites. RKPA 80258 is a weakly poikilitic plagioclase-poor mesosiderite, completely different from ALHA 77219, 81059, and 81098. On the other hand, RKPA 79015, 80229, 80246, and 80263 are very similar, belonging to subgroup C diogenitic mesosiderites. These mesosiderites contain orthopyroxene and recrystallized orthopyroxenite clasts in a metal-troilite matrix. The silicate fraction of mesosiderites ranged from diogenitic (RKPA 79015) to analogous to polymict eurcrite (Dyarrl Island). On the basis of petrologic data, the mesosiderite subdivision scheme was amended, making it possible to classify the formerly 'anomalous' RKPA 79015.

  16. Biological marker geochemistry and organic petrology of Chattanooga shale

    SciTech Connect

    Adams, J.P.; Kruge, M.A.; Bensley, D.F. (Southern Illinois Univ., Carbondale (USA))

    1989-08-01

    The Upper Devonian Chattanooga Shale is an extremely organic-rich unit containing up to 13% organic carbon, thus making it an important potential oil shale and/or petroleum source rock. Samples of the Chattanooga Shale from the periphery of the Nashville dome in central Tennessee and south-central Kentucky have been examined and grouped by maturity and organofacies, using biological marker geochemistry of extractable bitumen and organic petrology.

  17. Petrological evidence for secular cooling in mantle plumes.

    PubMed

    Herzberg, Claude; Gazel, Esteban

    2009-04-01

    Geological mapping and geochronological studies have shown much lower eruption rates for ocean island basalts (OIBs) in comparison with those of lavas from large igneous provinces (LIPs) such as oceanic plateaux and continental flood provinces. However, a quantitative petrological comparison has never been made between mantle source temperature and the extent of melting for OIB and LIP sources. Here we show that the MgO and FeO contents of Galapagos-related lavas and their primary magmas have decreased since the Cretaceous period. From petrological modelling, we infer that these changes reflect a cooling of the Galapagos mantle plume from a potential temperature of 1,560-1,620 degrees C in the Cretaceous to 1,500 degrees C at present. Iceland also exhibits secular cooling, in agreement with previous studies. Our work provides quantitative petrological evidence that, in general, mantle plumes for LIPs with Palaeocene-Permian ages were hotter and melted more extensively than plumes of more modern ocean islands. We interpret this to reflect episodic flow from lower-mantle domains that are lithologically and geochemically heterogeneous. PMID:19340079

  18. Exploration petrology of Sunoco Felda trend of south Florida

    SciTech Connect

    Mitchell-Tapping, H.

    1986-09-01

    The Sunoco Felda oil trend of the South Florida basin has been a prolific oil producer. All the oil is produced from the Cretaceous Sunniland formation, a leached limestone bioherm. Although the producing section has been considered reefal in the literature, petrographic and biostratigraphic analyses of various cores in producing fields have determined that these deposits are composed of particles of fragmented rudist and other fauna deposited in a tidal shoal. Atop this debris an algae and gastropod section has been deposited, typical of a mound deposited on a tidal mud flat. This model is exemplified in the Sunoco Felda and West Sunoco fields and was used in exploring the Sunoco Felda trend. From the petrological analysis of these two fields and from knowledge of other wells in the basin, biostratigraphic and lithologic trends can be determined and extended offshore into the eastern Gulf of Mexico. The author stresses petrology in exploring the Sunniland formation because correlating like responses on electric logs does not always result in correlating the same depositional facies - in fact, correlating like electric log responses in the Sunniland formation often results in correlating different facies. This study endeavors to analyze the Felda trend based on the petrological and petrophysical information obtained from the cores and logs. The author will show that the potential of the Sunniland formation may be greater than expected and that it may be the site of future major discoveries.

  19. Virtual Laboratories and Virtual Worlds

    NASA Astrophysics Data System (ADS)

    Hut, Piet

    2008-05-01

    Since we cannot put stars in a laboratory, astrophysicists had to wait till the invention of computers before becoming laboratory scientists. For half a century now, we have been conducting experiments in our virtual laboratories. However, we ourselves have remained behind the keyboard, with the screen of the monitor separating us from the world we are simulating. Recently, 3D on-line technology, developed first for games but now deployed in virtual worlds like Second Life, is beginning to make it possible for astrophysicists to enter their virtual labs themselves, in virtual form as avatars. This has several advantages, from new possibilities to explore the results of the simulations to a shared presence in a virtual lab with remote collaborators on different continents. I will report my experiences with the use of Qwaq Forums, a virtual world developed by a new company (see http://www.qwaq.com).

  20. Virtual Time

    Microsoft Academic Search

    David Jefferson

    1983-01-01

    Virtual time is a broad, new paradigm for organizing and synchronizing distributed systems, subsuming such heretofore distantly related problems as distributed discrete event simulation and distributed database concurrency control. It is an abstraction of real time in much the same way that virtual memory is an abstraction of real memory, and it reorganizes the concepts of concurrency and synchronization in

  1. Virtual flea

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a flea (Order Siphonaptera). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  2. Virtual grasshopper

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a grasshopper (Family Acrididae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  3. Virtual termite

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a termite (Order Isoptera). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  4. Virtual fly

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a blow fly (Family Calliphoridae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  5. Virtual mantis

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a mantis (Family Mantidae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  6. Virtual mosquito

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a mosquito (Family Culicidae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  7. Virtual bee

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a honey bee (Family Apidae *spelled Apiidae in the image caption*). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  8. Virtual Conferences.

    ERIC Educational Resources Information Center

    Bull, Glen; Bull, Gina; Garofalo, Joe; Sigmon, Tim

    1998-01-01

    So far classroom use of the Internet has been limited to asynchronous communication, but virtual conferencing will allow real-time connections between teachers and classrooms separated by continents. This article describes virtual conferencing applications: Chat, audio- and videoconferencing, electronic white boards, application sharing, and file…

  9. The Scanning Optical Microscope.

    ERIC Educational Resources Information Center

    Sheppard, C. J. R.

    1978-01-01

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

  10. Virtual Museums Pr. Robert Laurini Virtual Museums

    E-print Network

    Laurini, Robert

    Virtual Museums Pr. Robert Laurini 1 Virtual Museums Robert Laurini INSA de Lyon Virtual Museums · Cultural heritage · Real Museum (brick-and-mortar) and Virtual Museum · Multimedia information Virtual walls · 4 - Silk Road Virtual Museum · 5 - Conclusions 1 - Websites of existing museums · Vatican

  11. TEAM Electron Microscope Animation

    SciTech Connect

    None

    2012-01-01

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

  12. Characteristics of Moho transition zone: MCS reflection records and petrological aspects and physical properties

    Microsoft Academic Search

    J. Kasahara; K. Tsuruga; T. Ike; S. Unou; K. Koda

    2008-01-01

    The Moho is defined as the seismological discontinuity at the crust and mantle boundary. Its global depth, thickness of transition zone, and velocity structure has not been studied well. It is also poorly known whether the Moho has the same petrological and seismological properties in the continent and in the ocean, or not. Previous studies propose several petrological models for

  13. Petrologic characteristic and Geological Model of Igneous Reservoir: An example in Zhanhua Seg, Eastern China

    Microsoft Academic Search

    Q. Li; S. Shao; R. Kang; K. Liu

    2003-01-01

    The diabase is a typical igneous rock, which intrude the oil-bearing mudstone and form potential reservoir. As an example of Luo151 igneous rock in Zhanhua Seg, Eastern China, we studied the diabase reservoir in detail, including petrologic analysis, reservoir anisotropy and geological modeling. Four lithofacies zones are divided according to analyzing petrology, texture and structureoeªwhich comprise carbonaceous slate, hornfels containing

  14. Virtual Satellite

    NASA Technical Reports Server (NTRS)

    Hammrs, Stephan R.

    2008-01-01

    Virtual Satellite (VirtualSat) is a computer program that creates an environment that facilitates the development, verification, and validation of flight software for a single spacecraft or for multiple spacecraft flying in formation. In this environment, enhanced functionality and autonomy of navigation, guidance, and control systems of a spacecraft are provided by a virtual satellite that is, a computational model that simulates the dynamic behavior of the spacecraft. Within this environment, it is possible to execute any associated software, the development of which could benefit from knowledge of, and possible interaction (typically, exchange of data) with, the virtual satellite. Examples of associated software include programs for simulating spacecraft power and thermal- management systems. This environment is independent of the flight hardware that will eventually host the flight software, making it possible to develop the software simultaneously with, or even before, the hardware is delivered. Optionally, by use of interfaces included in VirtualSat, hardware can be used instead of simulated. The flight software, coded in the C or C++ programming language, is compilable and loadable into VirtualSat without any special modifications. Thus, VirtualSat can serve as a relatively inexpensive software test-bed for development test, integration, and post-launch maintenance of spacecraft flight software.

  15. Virtually Hawaii

    NSDL National Science Digital Library

    Virtually Hawaii is provided by researchers at the University of Hawaii, Proxemy Research, Terra Systems, and private company sponsors. Visitors can explore virtual field trips of the Hawaiian Islands, participate in remote sensing tutorials, work with an interactive spectral imager, view space and aircraft images, and more. The virtual field trip of the "big island" includes a simulated flight, a ground tour, a kids tour, and a link to six ways to enjoy Kilauea Volcano. An interesting and informative site, everyone from kids to grandparents will enjoy its content and ease of use.

  16. Virtual Wonders

    NSDL National Science Digital Library

    The British Natural History Museum has posted this site, which features a selection of fossils, meteorites, and other specimens that can be rotated and viewed in virtual reality. Each specimen is accompanied by a brief text description and links to additional information. This is a collection of strange and interesting virtual objects, most of which the viewer will not find in galleries. Virtual Wonders include a fossil ammonite, Anomalocaris model, Archaeopteryx skull, Coccolithopore, Radiolarian model, land snail shell, meteorite fragments, a two-faced sheep skull, fossil seashell, microfossil, specimen jar, surface of Mars, and trilobites.

  17. Virtual Colonoscopy

    MedlinePLUS

    ... virtual colonoscopy include exposure to radiation perforation—a hole or tear in the lining of the colon ... colonoscopy include exposure to radiation and perforation—a hole or tear in the lining of the colon. [ ...

  18. Virtual City

    NSDL National Science Digital Library

    1994-01-01

    In conjunction with Rice Design Alliance's Virtual City lecture series held earlier this year, home pages have been put up for two of the speakers, Howard Rheingold and Bruce Sterling, with access to online writings included.

  19. Virtual Cave

    NSDL National Science Digital Library

    2005-10-21

    This interactive resource adapted from The Virtual Cave by Dave Bunnell, presents images of various features found in solution caves and includes detailed information on how these features are formed and where they occur.

  20. Geochemical and petrological observations of gas transport at arc volcanoes

    NASA Astrophysics Data System (ADS)

    Edmonds, M.; Herd, R. A.; Humphreys, M.; Aiuppa, A.; Giudice, G.; Guida, R.; Moretti, R.; Christopher, T. E.; Rawson, H.

    2010-12-01

    Understanding the abundance and composition of vapour in magma chambers and the mechanisms of vapour transport in volcanic systems is of immense importance. Exsolved vapour in a magma storage area affects eruption style and duration, and influences ground deformation and other geophysical manifestations owing to its compressibility. Ultimately, we wish to understand how much pre-eruptive exsolved vapour exists and what role mafic magma supply at depth plays in supplying it. Soufriere Hills Volcano, Montserrat, has become an exceptionally well-monitored volcanic system and there is now an abundance of detailed geochemical and petrological information regarding magma degassing and gas transport processes. The eruption provides a unique opportunity to study the effects of open system mafic magma injection, mingling and degassing, which is occurring on the same time scale as eruption. We examine the geochemical and petrological evidence for magma mingling, degassing and gas fluxing at Soufriere Hills Volcano. We use measurements of gas flux and composition, using DOAS and a multigas sensor. We examine petrological and textural evidence for mafic magma supplying volatiles to the system, including evidence from phenocryst zoning and composition. We show that the mafic magma supplies volatiles as well as heat to the overlying resident andesite. Due to the strong partitioning of sulphur into a vapour phase at depth under oxidising conditions, the sulphur dissolved in the intruding mafic magma becomes segregated into vapour, along with carbon dioxide and water. The vapour is transported to the surface during both eruptive and non-eruptive periods, implying either that significant permeability exists within the system, or that magma convection operates. There is some evidence for gas fluxing, which suggests that gas may be transported through the magma. We draw comparisons with other recent studies of volatile transport in arc systems to show that some observations may be generic.

  1. Fluorescence spectroscopy: A promising tool for carbonate petrology

    SciTech Connect

    Vice, M.A.; Bensley, D.F.; Utgaard, J.E. (Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology)

    1992-01-01

    Responses of depositional and diagenetic components in samples of the Mission Canyon Limestone to blue-light excitation vary most noticeably with mineralogy and crystal size. The finely crystalline micrites, dolomicrites and argillaceous carbonates fluoresce more intensely than the more coarsely crystalline sparry calcite cements, dolospar cements and coarsely crystalline dolomites. Low intensity spectral analysis of cherts, anhydrites, and the carbonate phases provides an objective manner for quantifying fluorescence responses and for comparing them statistically. Nineteen of the optical parameters used in organic petrology are evaluated for their utility in carbonate petrology. Results of the discriminant function analysis suggest that red-weighted fluorescence chromaticity indices and yellow-weighted ones are more useful for mineral identification than the blue-weighted or equal-energy chromaticity indices. Statistical analysis of the optical data, mineralogy, and minor element compositions suggests correlations between the fluorescence responses and major minerals, carbonate diagenetic components, and the minor element geochemistry of carbonate components. Although no single element is identified as an activator of fluorescence in this study, the complex correlations of optical indices with Fe suggest that it does act to quench fluorescence. The four fluorescence cy chromaticity indices correlate significantly and positively with mineralogy and negatively with MgCo[sub 3]. In organic petrology, these indices are related to maceral content. The positive correlations of the four fluorescence cx chromaticity indices with Fe and Mn likely reflect fluorescence response to changes in compositions of pore fluids during diagenesis. This trend parallels the increase in cx indices with increasing maturation of organic materials.

  2. Hayden Planetarium: Virtual Observatory

    NSDL National Science Digital Library

    This online Hayden Planetarium resource explains the concept of the Virtual Observatory and contains links to the following eight sites: International Virtual Observatory Alliance, National Virtual Observatory, National Virtual Observatory Education and Outreach, Astrophysical Virtual Observatory, Canadian Virtual Observatory, AstroGrid, SkyView, and Theory in a Virtual Observatory.

  3. Mineralogic and petrologic studies of meteorites and lunar samples

    NASA Technical Reports Server (NTRS)

    Wood, J. A.

    1984-01-01

    During a 13 year period beginning in 1971, the Extraterrestrial Petrology Group examined lunar soils from all 6 Apollo missions and those returned by the Soviet Luna 16, Luna 20, and Luna 24 missions. In addition, the properties and apparent origin of the carbonaceous chondrites were examined. Chondrules, calcium-aluminum-rich inclusions (CAI) and the fine grained matrix materials that accompany chondrules and CAI's in primitive meteorites were investigated. The effects of planetary hydrothermal alteration of matrix materials in the C1 chondrite was also investigated. Full length papers and extended abstracts published during the grant are listed chronologically.

  4. Mineralogy and Petrology of COMET WILD2 Nucleus Samples

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Bland, Phil; Bradley, John; Brearley, Adrian; Brennan, Sean; Bridges, John; Brownlee, Donald; Butterworth, Anna; Dai, Zurong; Ebel, Denton

    2006-01-01

    The sample return capsule of the Stardust spacecraft will be recovered in northern Utah on January 15, 2006, and under nominal conditions it will be delivered to the new Stardust Curation Laboratory at the Johnson Space Center two days later. Within the first week we plan to begin the harvesting of aerogel cells, and the comet nucleus samples they contain for detailed analysis. By the time of the LPSC meeting we will have been analyzing selected removed grains for more than one month. This presentation will present the first results from the mineralogical and petrological analyses that will have been performed.

  5. Petrology of Two Itokawa Particles: Comparison with Equilibrated LL Chondrites

    NASA Technical Reports Server (NTRS)

    Komatsu, M.; Mikouchi, T.; Arai, T.; Fagan, T. J.; Zolensky, M.; Hagiya, K.; Ohsumi, K.; Karouji, Y.

    2015-01-01

    A strong link between Itokawa particles and LL chondrites was confirmed by preliminary examinations of Hayabusa particles [e.g., 1, 2]. Both poorly equilibrated and highly equilibrated particles have been found among the grains returned from Itokawa [1], and it is suggested that they correspond to LL4 and LL5-6, respectively. Here we report the petrography of two Itokawa particles and TEM study of one, and compare them to Antarctic LL chondrites with variable petrologic types (LL4-LL7) in order to understand the metamorphic history of asteroid Itokawa.

  6. Virtual Specimens

    NASA Astrophysics Data System (ADS)

    de Paor, D. G.

    2009-12-01

    Virtual Field Trips have been around almost as long as the Worldwide Web itself yet virtual explorers do not generally return to their desktops with folders full of virtual hand specimens. Collection of real specimens on fields trips for later analysis in the lab (or at least in the pub) has been an important part of classical field geoscience education and research for generations but concern for the landscape and for preservation of key outcrops from wanton destruction has lead to many restrictions. One of the author’s favorite outcrops was recently vandalized presumably by a geologist who felt the need to bash some of the world’s most spectacular buckle folds with a rock sledge. It is not surprising, therefore, that geologists sometimes leave fragile localities out of field trip itineraries. Once analyzed, most specimens repose in drawers or bins, never to be seen again. Some end up in teaching collections but recent pedagogical research shows that undergraduate students have difficulty relating specimens both to their collection location and ultimate provenance in the lithosphere. Virtual specimens can be created using 3D modeling software and imported into virtual globes such as Google Earth (GE) where, they may be linked to virtual field trip stops or restored to their source localities on the paleo-globe. Sensitive localities may be protected by placemark approximation. The GE application program interface (API) has a distinct advantage over the stand-alone GE application when it comes to viewing and manipulating virtual specimens. When instances of the virtual globe are embedded in web pages using the GE plug-in, Collada models of specimens can be manipulated with javascript controls residing in the enclosing HTML, permitting specimens to be magnified, rotated in 3D, and sliced. Associated analytical data may be linked into javascript and localities for comparison at various points on the globe referenced by ‘fetching’ KML. Virtual specimens open up new possibilities for distance learning, where design of effective lab exercises has long been an issue, and they permit independent evaluation of published field research by reviewers who do not have access to the physical field area. Although their creation can be labor intensive, the benefits of virtual specimens for education and research are potentially great. Interactive 3D Specimen of Sierra Granodiorite at Outcrop Location

  7. Cryogenic immersion microscope

    SciTech Connect

    Le Gros, Mark (Berkeley, CA); Larabell, Carolyn A. (Berkeley, CA)

    2010-12-14

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

  8. Virtual Labs

    NSDL National Science Digital Library

    Over the past few years, the Howard Hughes Medical Instituteâ??s Biointeractive website has garnered critical acclaim from a number of international organizations that evaluate various multimedia products that educate Internet users about science and technology. Most recently, their Virtual Labs area on the site has been well-received, and they are visually entrancing and easy to use. Currently, the site contains six full virtual labs, and they include those that allow students to learn how to identify various bacteria and another one that casts participants as a young intern who is learning how to identify heritable diseases of the heart. Each virtual lab contains resources for instructors, along with an interactive quiz.

  9. Virtual Hospital

    NSDL National Science Digital Library

    Provided and maintained by the University of Iowa Health Care, the Virtual Hospital is designed as a "medical reference and health promotion tool for health care providers and patients." To that end, the site offers current and authoritative medical information for patients and professional and pedagogical information for health care providers. The former includes patient educational briefs browseable by organ system or by a topical list, a collection of peer-reviewed and annotated Web resources, an internal search engine, and archives of a column offering medical advice to middle-aged users. Resources in the health care provider section include several digital libraries aimed at certain specialties (Pediatrics, Pediatric Radiology, Family Medicine, and Medical Student); multimedia textbooks and teaching files grouped by organ system; lectures and publications; and clinical practice guidelines. Additional resources at the site include links to the Virtual Children's and Virtual Naval Hospitals, an internal search engine, and online continuing education courses.

  10. Virtual Tower

    SciTech Connect

    Wayne, R.A. [Sandia National Labs., Albuquerque, NM (United States). Security Engineering Dept.

    1997-08-01

    The primary responsibility of an intrusion detection system (IDS) operator is to monitor the system, assess alarms, and summon and coordinate the response team when a threat is acknowledged. The tools currently provided to the operator are somewhat limited: monitors must be switched, keystrokes must be entered to call up intrusion sensor data, and communication with the response force must be maintained. The Virtual tower is an operator interface assembled from low-cost commercial-off-the-shelf hardware and software; it enables large amounts of data to be displayed in a virtual manner that provides instant recognition for the operator and increases assessment accuracy in alarm annunciator and control systems. This is accomplished by correlating and fusing the data into a 360-degree visual representation that employs color, auxiliary attributes, video, and directional audio to prompt the operator. The Virtual Tower would be a valuable low-cost enhancement to existing systems.

  11. Virtual Nerd

    NSDL National Science Digital Library

    Created by a team of experts and educators, the Virtual Nerd website offers a cornucopia of over 1200 videos designed to offer students help in math and science. All of the resources here are free for educators (others have to pay a fee to use the materials), and once they are registered they can get access to all of Virtual Nerd's step-by-step video tutorials which use their interactive whiteboard technology. First-time visitors can get started by clicking on the "Can I show you?" area to get an introduction to the Virtual Nerd website. Currently, the site covers pre-algebra, algebra, and introductory physics, with other topics to follow. The materials on the site are free for educators after completing a brief form. Finally, visitors can also check out their blog and follow them on Facebook and Twitter.

  12. Virtual Labs

    NSDL National Science Digital Library

    1969-12-31

    These virtual labs from the Howard Hughes Medical Institute allow students to experience laboratory procedures as if they were a professional scientist. Students can isolate and analyze bacterial DNA sequences, examine cardiac patients, dissect a leech, or diagnose diseases by detecting the presence of antibodies. These virtual labs include animated steps that must be performed, along with textual instructions and explanations so that students understand not only what they are doing, but also why they are doing it. This is an extensive Web site that offers a lot to learn, and a chance to have fun in the process.

  13. Photography through the Microscope.

    ERIC Educational Resources Information Center

    McNeil, D. W.

    1992-01-01

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

  14. Scanning Electron Microscope (SEM)

    USGS Multimedia Gallery

    SEM (Scanning electron Microscope) image of a vesicular ash particle erupted by Augustine volcano on January 13, 2006. The ash sample was collected during the ashfall in Homer, Alaska by John Paskievitch, AVO. The image was acquired by Pavel Izbekov using ISI-40 Scanning Electron Microscope at the A...

  15. Mailing microscope slides

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. The Light Microscope.

    ERIC Educational Resources Information Center

    Baker, W. L.

    1995-01-01

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

  17. Oman Ophiolite: Petrological and Geochemical Investigation of Fast-Spreading Crust Formation Processes

    NASA Astrophysics Data System (ADS)

    Müller, T.; Koepke, J.; Garbe-Schoenberg, C. D.; Schuth, S.; Wolff, P. E.

    2014-12-01

    We undertook a detailed field campaign in the Wadi Gideah, which is located in the Wadi-Tayin Massif in the southern part of the Oman Ophiolite, to sample a complete section of fast-spreading oceanic crust. Our concept of performing different analytical and structural investigations on the same samples enabled us to create a coherent data set. The thickness of the layered and virtually undeformed oceanic crust, containing pillow lavas and sheeted dikes as well as varitextured, foliated and layered gabbros resting on a relatively thin MOHO transition zone, was recalculated to approximately 6km. Here we present our data focusing on the petrological and geochemical logs obtained. Samples from the layered gabbro sequence show modal compositions of ~50 vol% plagioclase, ~40 vol% clinopyroxene and ~10 vol% olivine in average. The samples from the foliated gabbro sequence display a slightly higher amount of plagioclase. In very few samples up to 20 vol% of orthopyroxene is present. The layered gabbro sequence display Mg# 71-82 for olivine, Mg# 75-83 for clinopyroxene and An% in plagioclase of 71-93 mol%. The foliated gabbro sequence display Mg# 67-79 for olivine, Mg# 76-85 for clinopyroxene and An% in plagioclase of 58-85 mol%. The varitextured gabbro sequence display Mg# 74-80 for clinopyroxene and An% 59-86 in plagioclase mol%. The generally evolving trends in mineral major element composition from bottom to top of the profile are also observed for bulk rock major and trace element data. The average Sr87/Sr86 ratio is 0.7033 ± 0.0002 for the entire foliated and layered gabbro with significantly higher values for samples from fault zones cutting the gabbros at all crustal level which here are interpreted as possible hydrothermal pathways for cooling of the deep crust. We calculated the Wadi Gideah bulk crust composition and modeled possible fractionation paths, implying significant crystallization in the deep crust.

  18. Petrology and Geochemistry of D'Orbigny, Geochemistry of Sahara 99555, and the Origin of Angrites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Killgore, Marvin; Lee, Michael T.

    2001-01-01

    We have done detailed petrologic study of the angrite, D'Orbigny, and geochemical study of it and Sahara 99555. D'Orbigny is an igneous-textured rock composed of Ca-rich olivine, Al-Ti-diopside-hedenbergite, subcalcic kirschsteinite, two generations of hercynitic spinel and anorthite, with the mesostasis phases ulv6spinel, Ca-phosphate, a silicophosphate phase and Fe-sulfide. We report an unknown Fe-Ca-Al-Ti-silicate phase in the mesostasis not previously found in angrites. One hercynitic spinel is a large, rounded homogeneous grain of a different composition than the euhedral and zoned grains. We believe the former is a xenocryst, the first such described from angrites. The mafic phases are highly zoned; mg# of cores for olivine are approx.64, and for clinopyroxene approx.58, and both are zoned to Mg-free rims. The Ca content of olivine increases with decreasing mg#, until olivine with approx.20 mole% Ca is overgrown by subcalcic kirschsteinite with Ca approx.30-35 mole%. Detailed zoning sequences in olivine-subcalcic kirschsteinite and clinopyroxene show slight compositional reversals. There is no mineralogic control that can explain these reversals, and we believe they were likely caused by local additions of more primitive melt during crystallization of D'Orbigny. D'Orbigny is the most ferroan angrite with a bulk rock mg# of 32. Compositionally, it is virtually identical to Sahara 99555; the first set of compositionally identical angrites. Comparison with the other angrites shows that there is no simple petrogenetic sequence, partial melting with or without fractional crystallization, that can explain the angrite suite. Angra dos Reis remains a very anomalous angrite. Angrites show no evidence for the brecciation, shock, or impact or thermal metamorphism that affected the HED suite and ordinary chondrites. This suggests the angrite parent body may have followed a fundamentally different evolutionary path than did these other parent bodies.

  19. Virtual sound for virtual reality

    SciTech Connect

    Blattner, M.M. [Anderson (M.D.) Cancer Center, Houston, TX (United States). Dept. of Biomathematics]|[Lawrence Livermore National Lab., CA (United States)]|[California Univ., Davis, CA (United States); Papp, A.L. III [California Univ., Davis, CA (United States)]|[Lawrence Livermore National Lab., CA (United States)

    1993-02-01

    The computational limitations of real-time interactive computing do not meet our requirements for producing realistic images for virtual reality in a convincing manner. Regardless of the real-time restrictions on virtual reality interfaces, the representations can be no better than the graphics. Computer graphics is still limited in its ability to generate complex objects such as landscapes and humans. Nevertheless, useful and convincing visualizations are made through a variety of techniques. The central theme of this article is that a similar situation is true with sound for virtual reality. It is beyond our abilityto create interactive soundscapes that create a faithful reproduction of real world sounds, however, by choosing one`s application carefully and using sound to enhance a display rather than only mimic real-world scenes, a very effective use of sound can be made.

  20. Virtual sound for virtual reality

    SciTech Connect

    Blattner, M.M. (Anderson (M.D.) Cancer Center, Houston, TX (United States). Dept. of Biomathematics Lawrence Livermore National Lab., CA (United States) California Univ., Davis, CA (United States)); Papp, A.L. III (California Univ., Davis, CA (United States) Lawrence Livermore National Lab., CA (United States))

    1993-02-01

    The computational limitations of real-time interactive computing do not meet our requirements for producing realistic images for virtual reality in a convincing manner. Regardless of the real-time restrictions on virtual reality interfaces, the representations can be no better than the graphics. Computer graphics is still limited in its ability to generate complex objects such as landscapes and humans. Nevertheless, useful and convincing visualizations are made through a variety of techniques. The central theme of this article is that a similar situation is true with sound for virtual reality. It is beyond our abilityto create interactive soundscapes that create a faithful reproduction of real world sounds, however, by choosing one's application carefully and using sound to enhance a display rather than only mimic real-world scenes, a very effective use of sound can be made.

  1. Virtual colonoscopy.

    PubMed

    Vining, D J

    1999-02-01

    Virtual colonoscopy (VC) is an evolving technique that combines volume scanning and computer visualization methods to enable minimally invasive and effective colorectal cancer screening. Although VC offers significant clinical and public health advantages over conventional endoscopic screening, several issues confront VC's emergence into the medical marketplace. PMID:10036712

  2. Virtual colonoscopy

    Microsoft Academic Search

    David J Vining

    1999-01-01

    Virtual colonscopy (VC) is an evolving technique that combines volume scanning and computer visualization methods to enable minimally invasive and effective colorectal cancer screening. Although VC offers significant clinical and public health advantages over conventional endoscopic screening, several issues confront VC's emergence into the medical marketplace.

  3. Virtually There.

    ERIC Educational Resources Information Center

    Lanier, Jaron

    2001-01-01

    Describes tele-immersion, a new medium for human interaction enabled by digital technologies. It combines the display and interaction techniques of virtual reality with new vision technologies that transcend the traditional limitations of a camera. Tele-immersion stations observe people as moving sculptures without favoring a single point of view.…

  4. VIRTUAL GROWER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouses are complex systems. One management decision invariably influences another in often unexpected or unforeseen ways. Trial and error and “rules of thumb” are not a consistently profitable manner to make management decisions. A new computer-based management tool called Virtual Grower was...

  5. A Magnetic Petrology Database for Satellite Magnetic Anomaly Interpretations

    NASA Astrophysics Data System (ADS)

    Nazarova, K.; Wasilewski, P.; Didenko, A.; Genshaft, Y.; Pashkevich, I.

    2002-05-01

    A Magnetic Petrology Database (MPDB) is now being compiled at NASA/Goddard Space Flight Center in cooperation with Russian and Ukrainian Institutions. The purpose of this database is to provide the geomagnetic community with a comprehensive and user-friendly method of accessing magnetic petrology data via Internet for more realistic interpretation of satellite magnetic anomalies. Magnetic Petrology Data had been accumulated in NASA/Goddard Space Flight Center, United Institute of Physics of the Earth (Russia) and Institute of Geophysics (Ukraine) over several decades and now consists of many thousands of records of data in our archives. The MPDB was, and continues to be in big demand especially since recent launching in near Earth orbit of the mini-constellation of three satellites - Oersted (in 1999), Champ (in 2000), and SAC-C (in 2000) which will provide lithospheric magnetic maps with better spatial and amplitude resolution (about 1 nT). The MPDB is focused on lower crustal and upper mantle rocks and will include data on mantle xenoliths, serpentinized ultramafic rocks, granulites, iron quartzites and rocks from Archean-Proterozoic metamorphic sequences from all around the world. A substantial amount of data is coming from the area of unique Kursk Magnetic Anomaly and Kola Deep Borehole (which recovered 12 km of continental crust). A prototype MPDB can be found on the Geodynamics Branch web server of Goddard Space Flight Center at http://core2.gsfc.nasa.gov/terr_mag/magnpetr.html. The MPDB employs a searchable relational design and consists of 7 interrelated tables. The schema of database is shown at http://core2.gsfc.nasa.gov/terr_mag/doc.html. MySQL database server was utilized to implement MPDB. The SQL (Structured Query Language) is used to query the database. To present the results of queries on WEB and for WEB programming we utilized PHP scripting language and CGI scripts. The prototype MPDB is designed to search database by major satellite magnetic anomaly, tectonic structure, geographical location, rock type, magnetic properties, chemistry and reference, see http://core2.gsfc.nasa.gov/terr_mag/query1.html. The output of database is HTML structured table, text file, and downloadable file. This database will be very useful for studies of lithospheric satellite magnetic anomalies on the Earth and other terrestrial planets.

  6. Petrologic constraints on the pressure, temperature, time and composition of the Martian interior

    NASA Technical Reports Server (NTRS)

    Holloway, John R.

    1988-01-01

    Petrologic analysis of surface samples has been used to deduce pressure and temperature conditions existing in the crust and upper mantle at specific times in the Earth's history, as well as to estimate the chemical and mineralogical composition of the crust and upper mantle. The same techniques can be applied to samples of the Martian surface to provide P, T, time and composition constraints of the Martian interior. Estimates of P and T conditions existing at a given time would, in turn, provide strong constraints on the thermal evolution of Mars. Knowledge of the chemical and mineralogical composition of the Martian interior is of fundamental importance in assessing the early history of the solar system. A general petrological approach is outlined, describing the kinds of sample required, summarizing current understanding of the Martian interior based on experimental petrology, and outlining some of the important experiments needed to allow a full petrologic interpretation of Martian samples.

  7. JOURNAL OF PETROLOGY VOLUME 38 NUMBER 6 PAGES 757783 1997 Mineral Zoning, PTXM Phase Relations,

    E-print Network

    Spear, Frank S.

    petrologic analysis of ten meta-anorthosites and related INTRODUCTION rocks from the Adirondack highlands­T­X­M modeling of this reaction reveals a meta-anorthosite and related rocks with the goal ofP­T path

  8. Learning Activities for an Undergraduate Mineralogy/Petrology Course-"I Am/We Are."

    ERIC Educational Resources Information Center

    Goodell, Philip C.

    2001-01-01

    Introduces an entry level mineralogy/igneous petrology course designed for undergraduate students and presents a series of learning activities based on individual and cooperative learning. Includes 18 references. (Author/YDS)

  9. An Inquiry-Based Approach to Learning Petrology Using Student-Generated Data

    NSDL National Science Digital Library

    Karl Wirth

    The Petrology course at Macalester College is designed around a semester-long project. All laboratory and classroom activities within the course are directed toward understanding and solving a real-world problem, the origin and evolution of an intrusion in northern Minnesota. Emphasis is on using multi-disciplinary approaches, modern instrumentation, and student-generated data. After completing the course, students exhibit improved quantitative skills, reasoning, and understanding of fundamental petrologic processes.

  10. Apollo 15 yellow impact glasses: Chemistry, petrology, and exotic origin

    SciTech Connect

    Delano, J.W.; Lindsley, D.H.; Ma, M.; Schmitt, R.A.

    1982-11-15

    The Apollo 15 yellow impact glasses are characterized by moderate TiO/sub 2/ (approx.4.8%) and high abundances of the large ion lithophile elements (e.g., K, P, Hf, Th, REE). Since the chemistry of these glasses cannot be duplicated by any combination of local components presently known to occur at the Apollo 15 landing site, these yellow glasses seem to be exotic to that area. Chemical and petrologic constraints suggest that these samples were produced by impact melting of an immature mare regolith developed upon an unusual variety of mare basalt. We speculate that the target basalt were the youngest lava flows known to exist on the moon (i.e., Eratosphenian-age lavas in Oceanus Procellarum and Mare Imbrium). Specific tests are proposed for evaluating this provocative hypothesis.

  11. Petrology, chemistry, age and irradiation history of Luna 24 samples

    NASA Technical Reports Server (NTRS)

    Wasserburg, G. J.; Papanastassiou, D. A.; Mcculloch, M. T.; Huneke, J. C.; Dymek, R. F.; Depaolo, D. J.; Chodos, A. A.; Albee, A. L.; Radicati Di Brozolo, F.

    1978-01-01

    The results of petrological, chemical, isotopic age determination and irradiation studies of sample 24170 from the 170 cm depth of the regolith core returned from Mare Crisium by Luna 24 are presented. The sample is found to be comprised of fragments from a single igneous rock, with mineralogical evidence indicating it to be a mare basalt. The crystallization age is determined by Sm-Nd and Ar(40)-Ar(39) ages to be 3.30 AE, establishing the presence of relatively young flows. All soil samples show low trace element compositions with minimum contamination by KREEPUTh-rich materials. Rb-Sr and Sm-Nd relations reflect the absence of significant fractionation at ages younger than 4.5 AE. One soil sample shows extremely large neutron capture effects, imposing a new lower limit to the neutron production rate in the regolith and requiring the addition of irradiated materials from depth.

  12. Lunar ferroan anorthosite 60025 - Petrology and chemistry of mafic lithologies

    NASA Technical Reports Server (NTRS)

    James, O. B.; Mcgee, J. J.; Lindstrom, M. M.

    1991-01-01

    Eleven splits from the mafic-mineral-rich part of anorthosite 60025 were studied in order to establish the exact nature and causes of compositional variations in the minerals of lunar ferroan anorthosites. All splits were analyzed by INAA, and five were studied intensively by petrologic techniques. All splits were found to have similar cataclastic textures and show textural evidence of at least two episodes of deformation. The whole-rock split contains mafic minerals having a wide range of compositions and is probably polymict. It is suggested that the rare-earth patterns for all splits can be duplicated safactorily, assuming that the equilibrium liquids had flat, or nearly flat, chondrite-normalized rare-earth patterns. The plagioclases in all splits were found to be identical. Data obtained indicate that in ferroan anorthosites An content in plagioclase and mg' of associated mafic minerals are not strongly correlated.

  13. Petrology and geochemistry of alkali gabbronorites from lunar breccia 67975

    NASA Technical Reports Server (NTRS)

    James, Odette B.; Flohr, Marta K.; Lindstrom, Marilyn M.

    1987-01-01

    Detailed results of petrologic and compositional studies of three clasts found in thin sections of the Apollo 16 lunar breccia 67975 and of four clasts extracted from the breccia (for instrumental neutron activation analysis) prior to thin sectioning are reported. The alkali gabbronorites of the breccia form two distinct subgroups, magnesian and ferroan. The magnesian gabbronorites are composed of bytownitic plagioclase, hypersthene, augite, a silica mineral, and trace Ba-rich K-feldspar. The ferroan gabbronorites are composed of ternary plagioclase, pigeonite, augite, Ba-rich K-feldspar, and a silica mineral. Trace minerals in both subgroups are apatite, REE-rich whitlockite, and zircon. The magnesian and ferroan alkali gabbronorites appear to have formed by progressive differentiation of the same, or closely related, parent REE-rich magmas.

  14. Is Virtual Reality Virtually Here?

    ERIC Educational Resources Information Center

    Carr, Clay

    1992-01-01

    Virtual reality, a three-dimensional simulation technology, may best be used (1) when training mistakes would be costly; (2) when the environment cannot be experienced in the real world; (3) to improve human-machine interfaces; (4) to make training situations real; and (5) to make the perceptible imperceptible. (SK)

  15. Virtual instrumentation and virtual environments

    Microsoft Academic Search

    H. J. W. Spoelder

    1999-01-01

    The objective of this work is to chart intriguing new possibilities and challenges resulting from the driving force and enabling factors of computing power and bandwidth that lie ahead of the instrumentation-and-measurement community. We do so by describing research and applications on the boundary between measurement, instrumentation, and virtual environments, and elucidate trends with some examples. We focus on three

  16. Virtual reflected-light microscopy.

    PubMed

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

    2011-12-01

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

  17. [Microscopic colitis: update 2014].

    PubMed

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

    2014-09-01

    Microscopic colitis, which includes lymphocytic colitis and collagenous colitis, represents a frequent cause of chronic watery diarrhea especially in the elderly population. Several medications, such as nonsteroidal antiinflammatory drugs, proton pump inhibitors or antidepressants, as well as cigarette smoking have been recognized as risk factors for microscopic colitis. The diagnosis of microscopic colitis is based on a macroscopically normal ileo-colonoscopy and several biopsies from the entire colon, which demonstrate the pathognomonic histopathologic findings. Therapy is mainly based on the use of budesonide. Other medications, such as mesalazine, cholestyramine and bismuth, have been evaluated as well but the evidence is less solid. PMID:25276996

  18. Virtual Reality and Abstract Data: Virtualizing Information

    E-print Network

    Spring, Michael B.

    Virtual Reality and Abstract Data: Virtualizing Information by Michael B. Spring and Michael C. Jennings Department of Information Science University of Pittsburgh Abstract Virtual reality interfaces may be employed in creating a map- ping between abstract data and dimensions of a virtual reality. I. Introduction

  19. A portable laser photostimulation and imaging microscope

    PubMed Central

    Nikolenko, Volodymyr; Peterka, Darcy S.; Yuste, Rafael

    2013-01-01

    We describe a compact microscope that uses a Spatial Light Modulator (SLM) to control the excitation laser light. The flexibility of SLMs, which can mimic virtually any optical transfer function, enables the experimenter to create, in software, arbitrary spatio-temporal light patterns, including focusing and beam scanning, simply by calculating the appropriate phase mask. Our prototype, a scan-less device with no moving parts, can be used for laser imaging or photostimulation, supplanting the need for an elaborate optical setup. As a proof of principle, we generate complex excitation patterns on fluorescent samples and also perform functional imaging of neuronal activity in living brain slices. PMID:20644244

  20. Virtual Autopsy

    NSDL National Science Digital Library

    Designed with medical students in mind, Leicester (England) University's Virtual Autopsy site takes the student on a virtual tour of seven autopsies. Several options allow for efficient navigation of the site: Cause of Death is a self-assessment quiz students may take after "performing" each autopsy; Return to History takes the user back to the beginning of each case; and Choose another Case lets the user move between the seven cases. Each case contains nearly a dozen detailed color images of certain key parts (including tissues) of the human anatomy--lung, body, heart, head--with hyperlinks to further information. By clicking on the dictionary icon, for instance, a student links to a pop-up page with detailed descriptions of that particular condition. Aspiring pathologists are sure to find this worthwhile, and the absence of gruesome images makes it a good learning site for many budding medical scientists as well.

  1. Virtual Polyhedra

    NSDL National Science Digital Library

    Hart, George W. (George William), 1955-

    A growing collection of over 1000 virtual reality polyhedra to explore, complementing Hart's Pavilion of Polyhedreality. Includes instructions for building paper models of polyhedra including modular origami, with ideas for classroom use. Each of the sections contains background information and exercises, a list of virtual reality models, and links to further topics. Platonic Solids (Regular Convex Polyhedra); Kepler-Poinsot Polyhedra (Regular NonConvex Polyhedra); Archimedean Polyhedra (Semi-Regular Convex Polyhedra); Prisms and Anti-Prisms; Archimedean Duals; Quasi-Regular Polyhedra; Johnson Solids (the remaining convex polyhedra with regular faces); Pyramids, Dipyramids, and Trapezohedra; Compound Polyhedra - Introduction; Stellated Polyhedra - Introduction; Compounds of Cubes; Convex Deltahedra; Zonohedra; Uniform Polyhedra; Uniform Compounds of Uniform Polyhedra; Stellations of the Icosahedron; Stellations of the Rhombic Triacontahedron; Other Good Stuff: Alphabetic list of articles, Alphabetic listing of all the polyhedra models, a Glossary, and an Annotated Bibliography. Also background material on polygons and on polyhedron names.

  2. Microscope collision protection apparatus

    DOEpatents

    DeNure, Charles R. (Pocatello, ID)

    2001-10-23

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

  3. Virtual Dice

    NSDL National Science Digital Library

    BBC Online Services

    2012-01-01

    This interactive Flash applet contains a set of four virtual dice with 6, 8, 10 and 12 faces. Clicking a chosen die generates a random value. The values on each die can be customized with the user's own choices to provide flexibility. These values can be up to five digits long and include either positive, negative or a combination of numbers, and can include text or symbols. The dice can be used to generate random numbers in game situations or in studying probability.

  4. Virtual Mirrors

    NASA Astrophysics Data System (ADS)

    Greenslade, Thomas B.

    2010-01-01

    The multiple-reflection photograph in Fig. 1 was taken in an elevator on board the cruise ship Norwegian Jade in March 2008. Three of the four walls of the elevator were mirrored, allowing me to see the combination of two standard arrangements of plane mirrors: two mirrors set at 90° to each other and two parallel mirrors. Optical phenomena of this complexity are most easily approached by the Method of Virtual Mirrors.

  5. Virtual Sky

    NSDL National Science Digital Library

    The Virtual Sky Viewer is sponsored by The Center for Advanced Computing Research at the California Institute of Technology and the Microsoft Corporation. The Web site allows users to view "stunning, seamless images of the night sky; not just an album of popular places, but the entire northern sky at high resolution". Although reading the help link before attempting to use the viewer is recommend, the powerful application gives fascinating and unique views of the sky that most people have never seen. >.

  6. Virtual Reality

    Microsoft Academic Search

    2006-01-01

    Abstract vjVTK is a small toolkit enabling the use of the Visualization ToolKit (VTK) native ly within the VRJuggler Virtual Reality framework. The toolkit enables a departure from the traditional v isualization calculation-conversionimmersive,viewing cycle. vjVTK leverages the OpenGL capabilities of VTK to a llow it to run as a native graphics generation tool within the VRJuggler framework. This removes,the need

  7. Virtual Sojourner

    NSDL National Science Digital Library

    Richard Edgerton

    This module has students carry out a virtual Mars mission similar to Pathfinder's rover, the Sojourner. Students work in teams, concentrating on specific mission needs, such as engineering, camera, navigation, or science. The activities in this module simulate the Mars Pathfinder mission objectives and structure. The purpose of this module is for students to work collaboratively to map, invent, and solve navigation problems with a 'remote' classroom.

  8. Virtual Volcano

    NSDL National Science Digital Library

    The Discovery Channel's website has several interactive features on volcanoes to complement its programs on Pompeii. At the homepage, visitors can explore a virtual volcano, by clicking on "Enter". The virtual volcano has several components. The first is a quickly revolving globe with red triangles and gray lines on it that represent active volcanoes and plate boundaries. Clicking on "Stop Rotation", located next to the globe, will enable a better look. Visitors can also click one of the topics below the globe, to see illustrations of "Tectonic Plates", "Ring of Fire" (no, not the Johnny Cash song), and "Layers Within". Visitors can click on "Build your Own Volcano and Watch it Erupt" on the menu on the left side of the page, where they will be given a brief explanation of two factors that affect the shape and explosiveness of volcanoes: viscosity and gas. Then they must choose, and set, the conditions of their volcano by using the arrows under the viscosity and gas headings, and clicking on "Set Conditions", underneath the arrows. Once done, a description of the type of volcano created will be given, and it's time to "Start Eruption". While the lava flows, and the noise of an eruption sounds, terms describing various features of the volcano are superimposed on the virtual volcano, and can be clicked on for explanations.

  9. A virtual class calculus

    Microsoft Academic Search

    Erik Ernst; Klaus Ostermann; William R. Cook

    2006-01-01

    Virtual classes are class-valued attributes of objects. Like virtual methods, virtual classes are defined in an object's class and may be redefined within sub- classes. They resemble inner classes, which are also defined within a class, but virtual classes are accessed through object instances, not as static components of a class. When used as types, virtual classes de- pend upon

  10. Isotopic Petrology: The Curious Case of the Shergottite Meteorites

    NASA Astrophysics Data System (ADS)

    Jones, J. H.

    2009-05-01

    The shergottites comprise a diverse suite of martian basalts and basaltic cumulates. As of 1985, there were three proposed igneous ages for this group of basaltic rocks: (i) 4-4.5 b.y. [1; Caltech]; (ii) 1.3 b.y. [2; JSC]; and (iii) 360 m.y. [3; Mainz]. At that time I proffered that petrographic observations demanded that the shergottites were only 180 m.y. old [4]. By 1985, all the above geochronology groups had presented evidence of a young 200 m.y. age, but interpreted that as a metamorphic resetting. My observation was considered extremely controversial. However, John Longhi was instrumental, perhaps pivotal, in causing this new, controversial interpretation to be accepted, at least among petrologists. John then used this newfound knowledge to infer the Nd isotopic composition of the martian crust [5]. This new interpretation of shergottite chronology has led to petrologic insights that would not otherwise have been possible: (I) There were melt extraction events in the shergottite mantle immediately(?) preceding shergottite formation; and (II) the variation in enriched vs. depleted characteristics of the shergottites is best explained by assimilation of ancient, enriched crust by young magmas from a depleted source region. I. Internal, mineral isochrons of the shergottites (15 years later) vary from 165 m.y. to 575 m.y. [6]. Without exception, the Sm/Nd ratios of the shergottites themselves are larger than the time-integrated Sm/Nd ratio of their source regions [7]. This means that there has been a LREE-enriched phase that has fractionated from the shergottites. There are no solid phases in the martian mantle that are capable of this. This implies that LREE-enriched magmas escaped the shergottite source regions just prior to shergottite petrogenesis. II. Therefore, the shergottites can be characterized in terms of three Sm-Nd components: (i) a primitive shergottite magma from a depleted source region; (ii) an enriched crust; and (iii) a missing LREE-enriched melt. Interestingly, the 180 m.y. shergottites require only two Sm-Nd components, because they fall along a two-component mixing line. This implies that these shergottites were derived from a single magma, that was generated from a single, LREE-melt-extracted source region, which subsequently assimilated various amounts of enriched crust. Otherwise, the amount of assimilated crust for each shergottite would be required to be linked to the amount of missing, LREE-enriched magma, in such a way that a two-component linear array is generated. Since LREE melt extraction had to occur before depleted-shergottite petrogenesis and since crustal assimilation must have occurred after, these two physical processes have little chance of being coupled. In addition, this linear shergottite mixing array must be of sufficient quality that it could initially be interpreted as an isochron [2]. This interpretation of 180 m.y. shergottite petrogenesis reinforces Longhi's inference of the Nd isotopic composition of the martian crust [5], at least in one particular martian terrain. Bottom line: In order to understand martian chronology, you have to understand martian petrology. And in order to understand martian petrology, you have to understand martian chronology. This is an aphorism that (I think) John would endorse. [1] Chen and Wassserburg (1986) Geochim. Cosmochim. Acta 50, 955-968. [2] Shih et al. (1982 Geochim. Cosmochim. Acta 46, 2323-2344. [3] Jagoutz and Wanke (1986) Geochim. Cosmochim. Acta 50, 939-953. [4] Jones (1986) Geochim. Cosmochim. Acta 50, 969-977. [5] Longhi (1991) Proc. Lunar Planet. Sci. Conf. 21st, 695-709. [6] Nyquist et al. (2001) In Chronology and Evolution of Mars 96, pp. 105-164. [7] Borg (2003) Geochim. Cosmochim. Acta 67, 3519-3536.

  11. Linking Petrology and Seismology at an Active Volcano

    NASA Astrophysics Data System (ADS)

    Saunders, K.; Blundy, J.; Dohmen, R.; Cashman, K.

    2012-12-01

    Many active volcanoes are continuously monitored through a variety of techniques including seismicity and gas emissions looking for signs of unrest that may signal an impending eruption. One of the enduring challenges is to link the monitored signal to the actual magmatic processes. This is complicated as a magma sample can only be obtained through a subsequent volcanic eruption. Crystals grown within the sub-volcanic plumbing system have the potential to preserve a record of the evolving magma within their crystal structure from nucleation to eruption. Perturbations within the magma system, such as change in temperature, water content or magma mixing causes renewed crystal growth of a different composition creating zoned crystals. Chemical fingerprinting of individual crystal zones allow us to decipher the magmatic processes that created the zonation. Importantly, diffusion chronometry (relaxation of elements across compositional interfaces) enables us to calculate timescales of magmatic perturbations within the magma chamber prior to eruption. Applying these techniques to recent well-characterised eruptions with well-known eruption dates for samples enables us to calculate a petrological time series that can be correlated with geophysical constrained time series form the same eruption to ascertain links to pre-eruptive processes. Mount St. Helens produced a series of well-studied eruptions and characterised eruptions between 1980-1986. From nine of these eruptions, over 500 orthopyroxene crystals were interrogated through a combination of high-resolution imaging and chemical fingering by scanning electron microscopy and electron probe microanalyser respectively. Multiple crystal populations were observed of both unzoned and zoned orthopyroxene with no distinct chemical heterogeneities between these two populations. Zoned crystals were further subdivided into: (1) normally zoned crystals (Fe-rich rims); (2) reversed zoned crystals (Mg-rich rims); (3) multiple zoned crystals and; (4) patchy zoned crystals. Diffusion chronometry indicates both Fe-rich and Mg-rich rims grew simultaneously and generally within two years prior to eruption. Peaks in crystallisation are correlative with peaks in seismicity and gas emissions. Establishing that important but elusive evidence that clearly shows a relationship between seismicity and magma movement and shows that geophysical monitoring techniques do record an accurate arrival of magma pulses. Such a correlation as shown in this study strongly suggests that petrologic time series from ancient or recently re-active volcanic centres where monitoring is limited can provide fundamental insights in pass volcanic activity and can be used to help with mitigation for future eruptions.

  12. A cytogeneticist's microscope.

    PubMed

    Green, D K; Bayley, R; Rutovitz, D

    1977-05-01

    It is demonstrated that there are a number of advantages in using a mechanised microscope for scoring a large number of metaphase cells from human blood lymphocyte preparations. Following the development of an automatic metaphase spread finding machine based upon a large motorised microscope and a synchronous closed circuit television camera and flashing light source, a much smaller machine which is more appropriate to the cytogenetics laboratory, but with a similar metaphase finding performance has been constructed. The new machine which consists of a Cambridge Instruments 1 micron stepping microscope stage, a linear diode array scanner and a computer is described in detail. Metaphase finding performance figures for various orcein stained human blood lymphocyte preparations are given. PMID:865291

  13. Integrated elastic microscope device

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

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

  14. A Virtual Microscope for Academic Medical Education: The Pate Project

    PubMed Central

    Hundt, Christian; Schmitt, Volker H; Schömer, Elmar; Kirkpatrick, C James

    2015-01-01

    Background Whole-slide imaging (WSI) has become more prominent and continues to gain in importance in student teaching. Applications with different scope have been developed. Many of these applications have either technical or design shortcomings. Objective To design a survey to determine student expectations of WSI applications for teaching histological and pathological diagnosis. To develop a new WSI application based on the findings of the survey. Methods A total of 216 students were questioned about their experiences and expectations of WSI applications, as well as favorable and undesired features. The survey included 14 multiple choice and two essay questions. Based on the survey, we developed a new WSI application called Pate utilizing open source technologies. Results The survey sample included 216 students—62.0% (134) women and 36.1% (78) men. Out of 216 students, 4 (1.9%) did not disclose their gender. The best-known preexisting WSI applications included Mainzer Histo Maps (199/216, 92.1%), Histoweb Tübingen (16/216, 7.4%), and Histonet Ulm (8/216, 3.7%). Desired features for the students were latitude in the slides (190/216, 88.0%), histological (191/216, 88.4%) and pathological (186/216, 86.1%) annotations, points of interest (181/216, 83.8%), background information (146/216, 67.6%), and auxiliary informational texts (113/216, 52.3%). By contrast, a discussion forum was far less important (9/216, 4.2%) for the students. Conclusions The survey revealed that the students appreciate a rich feature set, including WSI functionality, points of interest, auxiliary informational texts, and annotations. The development of Pate was significantly influenced by the findings of the survey. Although Pate currently has some issues with the Zoomify file format, it could be shown that Web technologies are capable of providing a high-performance WSI experience, as well as a rich feature set. PMID:25963527

  15. Using virtual menus in a virtual environment

    NASA Technical Reports Server (NTRS)

    Jacoby, Richard H.; Ellis, Stephen R.

    1992-01-01

    Virtual environment interfaces to computer programs in several diverse application areas are currently being developed. The users of virtual environments will require many different methods to interact with the environments and the objects in them. This paper reports on our use of virtual menus as a method of interacting with virtual environments. Several aspects of virtual environments make menu interactions different from interactions with conventional menus. We review the relevant aspects of conventional menus and virtual environments, in order to provide a frame of reference for the design of virtual menus. We discuss the features and interaction methodologies of two different versions of virtual menus which have been developed and used in our lab. We also examine the problems associated with our original version, and the enhancements incorporated into our current version.

  16. Lithospheric petrology beneath the northern part of the Arabian Plate in Syria: evidence from xenoliths in alkali basalts

    Microsoft Academic Search

    Sobhi Nasir; Abdulrahman Safarjalani

    2000-01-01

    A petrological model for the upper mantle and lower crust under the northern part of the Arabian Plate (Syria) has been derived on the basis of petrology of upper mantle and lower crustal xenoliths occurring in the Neogene to Quaternary alkali basalts of the Shamah volcanic fields. The xenolith suite has been classified by texture mineralogy and chemistry into the

  17. Petrology of New Stannern-trend Eucrites and Eucrite Genesis

    NASA Technical Reports Server (NTRS)

    Gardner, K. G.; Mittlefehldt, D. W.

    2004-01-01

    Eucrites are basaltic meteorites of the howardite-eucrite-diogenite (HED) suite that originated on a differentiated asteroid, possibly 4 Vesta. Basaltic eucrites are divided into three subgroups based on composition: main group, Stannern-trend, and Nuevo Laredo-trend. The main group and Nuevo Laredo-trend define a sequence formed by fractional crystallization of pigeonite and plagioclase from primitive parent melts [2, 3]. The Stannern-trend cannot be explained this way, but may rather represent a partial-melt sequence of their parent body. However, this model seems inadequate to explain eucrite siderophile element contents, and it is difficult to develop a single unifying model for petrogenesis of all eucrites. Until recently, there were only four Stannern- trend eucrites. One is an anomalous partial cumulate. There is little geochemical variation among these meteorites, so the Stannern-trend was poorly defined. Geochemical studies have identified four additional eucrites as members of the Stannern-trend; one extends the Stannern-trend closer to the main group [5]. No detailed descriptions of these rocks have been published. In order to better integrate these eucrites into the suite, we have done petrologic study of them. They are: LEW 88010, PCA 82501, PCA 91006 and PCA 91179.

  18. The clinical specular microscope

    Microsoft Academic Search

    C. D. Binkhorst; L. H. Loones; P. Nygaard

    1977-01-01

    The principle and technique of Maurice's (1968) method of microscopy of the corneal endothelium at high magnification is discussed. An instrument is now available for clinical use (clinical specular microscope). Literature reports on endothelial cell size and abnormalities in normal eyes and in eyes after surgery are critically evaluated and the personal experience of the authors in pseudophakic patients is

  19. Exploring Tools: Special Microscopes

    NSDL National Science Digital Library

    Nanoscale Informal Science Education Network

    2010-01-01

    In this activity, learners use a flexible magnet as a model for a scanning probe microscope (SPM). They learn that SPMs are an example of a special tool that scientists use to work on the nanoscale. Use this activity to talk about different tools that scientists use to study the nanoscale.

  20. Microscope on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

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

  1. Virtual Laboratory

    NSDL National Science Digital Library

    2012-04-27

    The website for the Virtual Laboratory contains a bold and direct statement: "Conventional teaching all too often accepts memorization and pattern recognition as true learning" After reading this statement, it makes sense that the goal of this site is "to help students to recognize, confront, correct, and expand their understanding of subject or a technique." The site contains five different sets of course materials that use interactive materials, short quizzes, and embedded demonstrations to assist students and teachers alike. One set of materials that should not be missed is in the Teaching & Learning Biology area. Here visitors will find links, fact sheets, and pedagogical suggestions for teaching a college-level biology course. Moving on, the Chemistry, Life, the Universe and Everything section contains a new perspective on how to reform the garden-variety general chemistry course.

  2. Petrology and In Situ Trace Element Chemistry of a Suite of R Chondrites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Peng, Z. X.; Torrano, Z. A.

    2015-01-01

    Rumuruti (R) chondrites are characterized by low chondrule/matrix modal ratios, high oxidation state, small mean chondrule size, abundant sulfides and low metal contents, and are of petrologic types 3 to 6 [1, 2]. LAP 04840 (R5, [3]) and MIL 11207 (R6), contain the high-T hydrous phases amphibole and mica [3, 4]; not all equilibrated R chondrites contain these [2]. R chondrites thus can provide evidence on whether there are compositional effects caused by high-T, high-fluid metamorphism of nebular materials. We are investigating a suite of R chondrites of diverse petrologic grades to further understand the nature of the metamorphic processes that engendered them [5]. We report on our petrological studies, plus preliminary in situ analyses of trace elements in amphibole-bearing R chondrites.

  3. Petrology of the Crystalline Rocks Hosting the Santa Fe Impact Structure

    NASA Technical Reports Server (NTRS)

    Schrader, C. M.; Cohen, B. A.

    2010-01-01

    We collected samples from within the area of shatter cone occurrence and for approximately 8 kilometers (map distance) along the roadway. Our primary goal is to date the impact. Our secondary goal is to use the petrology and Ar systematics to provide further insight into size and scale of the impact. Our approach is to: Conduct a detailed petrology study to identify lithologies that share petrologic characteristics and tectonic histories but with differing degrees of shock. Obtain micro-cores of K-bearing minerals from multiple samples for Ar-40/Ar-39 analysis. Examine the Ar diffusion patterns for multiple minerals in multiple shocked and control samples. This will help us to better understand outcrop and regional scale relationships among rocks and their responses to the impact event.

  4. Interacting With Virtual Reality

    Microsoft Academic Search

    M. M. Wloka

    1995-01-01

    Interacting with virtual reality is fundamentally different from interacing with traditional desktopgraphics. The three features that characterize virtual reality interaction are immersion, richinteraction and presence; I define these features. To achieve them, virtual reality system designersneed to address many different issues. I discuss some of these issues, in particular multipleinputs, multiple outputs, multiple participants, dynamic virtual worlds, user interface paradigmsand...

  5. Virtual Worlds, Real Learning

    ERIC Educational Resources Information Center

    Meyers, Eric M.

    2009-01-01

    Many children between the ages of four and twelve log in to Web-based virtual play spaces each day, and these virtual worlds are quickly becoming an important aspect of their out-of-school lives. Consequently, educators' challenge is to see how they can leverage virtual spaces, such as the virtual play spaces, for learning and literacy. Over the…

  6. Rethinking Virtual School

    ERIC Educational Resources Information Center

    Schomburg, Gary; Rippeth, Michelle

    2009-01-01

    Virtual schooling has been touted as one of the best ways to meet the needs of at-risk students, but what happens when a district's virtual education program is unsuccessful? That was the problem in Eastern Local School District, a small rural district in Beaver, Ohio. The district contracted virtual school services and used the virtual school for…

  7. The formation of chondrules: petrologic tests of the shock wave model

    PubMed

    Connolly Jr HC; Love

    1998-04-01

    Chondrules are millimeter-sized rounded igneous rocks within chondritic meteorites. Their textures and fractionated mineral chemistries suggest that they formed by repeated, localized, brief (minutes to hours) melting of cold aggregates of mineral dust in the protoplanetary nebula. Astrophysical models of chondrule formation have been unable to explain the petrologically diverse nature of chondrites. However, a nebular shock wave model for chondrule formation agrees with many of the observed petrologic and geochemical properties of chondrules and shows how particles within the nebula are sorted by size and how rims around chondrules are formed. It also explains the volatile-rich nature of chondrule rims and the chondrite matrix. PMID:9525858

  8. Measuring virtual wealth in virtual worlds Jingzhi Guo Zhiguo Gong

    E-print Network

    Guo, Jingzhi

    Measuring virtual wealth in virtual worlds Jingzhi Guo · Zhiguo Gong Published online: 21 January on measuring virtual wealth in an open virtual world for diagnosing the health of virtual worlds. It proved the existence of an open virtual world by proving the existence of a free choice of virtual currencies

  9. Adaptive Scanning Optical Microscope A multidisciplinary optical microscope

    E-print Network

    Wen, John Ting-Yung

    . Hecht, Optics, 4th ed. (Addison Wesley, 2001). 9. D. B. Murphy, Fundamentals of Light Microscopy (WileyAdaptive Scanning Optical Microscope (ASOM): A multidisciplinary optical microscope design, the optical microscope remains one of the most important tools for observing below the threshold of the naked

  10. Geophysical, petrological and mineral physics constraints on Earth's surface topography

    NASA Astrophysics Data System (ADS)

    Guerri, Mattia; Cammarano, Fabio; Tackley, Paul J.

    2015-04-01

    Earth's surface topography is controlled by isostatically compensated density variations within the lithosphere, but dynamic topography - i.e. the topography due to adjustment of surface to mantle convection - is an important component, specially at a global scale. In order to separate these two components it is fundamental to estimate crustal and mantle density structure and rheological properties. Usually, crustal density is constrained from interpretation of available seismic data (mostly VP profiles) based on empirical relationships such those in Brocher [2005]. Mantle density structure is inferred from seismic tomography models. Constant coefficients are used to interpret seismic velocity anomalies in density anomalies. These simplified methods are unable to model the effects that pressure and temperature variations have on mineralogical assemblage and physical properties. Our approach is based on a multidisciplinary method that involves geophysical observables, mineral physics constraints, and petrological data. Mantle density is based on the thermal interpretation of global seismic tomography models assuming various compositional structures, as in Cammarano et al. [2011]. We further constrain the top 150 km by including heat-flow data and considering the thermal evolution of the oceanic lithosphere. Crustal density is calculated as in Guerri and Cammarano [2015] performing thermodynamic modeling of various average chemical compositions proposed for the crust. The modeling, performed with the code PerpleX [Connolly, 2005], relies on the thermodynamic dataset from Holland and Powell [1998]. Compressional waves velocity and crustal layers thickness from the model CRUST 1.0 [Laske et al., 2013] offer additional constrains. The resulting lithospheric density models are tested against gravity (GOCE) data. Various crustal and mantle density models have been tested in order to ascertain the effects that uncertainties in the estimate of those features have on the modeled topography. We also test several viscosity models, either radially symmetric, the V1 profile from Mitrovica and Forte [2004], or more complex laterally varying structures. All the property fields are expanded in spherical harmonics, until degree 24, and implemented in the code StagYY [Tackley, 2008] to perform mantle instantaneous flow modeling and compute surface topography and gravitational field. Our results show the importance of constraining the crustal and mantle density structure relying on a multidisciplinary approach that involves experimentally robust thermodynamic datasets. Crustal density field has a strong effect on the isostatic component of topography. The models that we test, CRUST 1.0 and those in Guerri and Cammarano [2015], produce strong differences in the computed isostatic topography, in the range ±600 m. For the lithospheric mantle, relying on experimentally robust material properties constraints is necessary to infer a reliable density model that takes into account chemical heterogeneities. This approach is also fundamental to correctly interpret seismic models in temperature, a crucial parameter, necessary to determine the lithosphere-asthenosphere boundary, where static effects on topography leave place to dynamic ones. The comparison between results obtained with different viscosity fields, either radially symmetric or vertically and laterally varying, shows how lateral viscosity variations affect the results, in particular the modeled geoid, at different wavelengths. References: Brocher, T. M. (2005), Empirical Relations between Elastic Wavespeeds and Density in the Earth's Crust, Bulletin of the Seismological Society of America, 95(6), 2081-2092. Cammarano, F., P. J. Tackley, and L. Boschi (2011), Seismic, petrological and geodynamical constraints on thermal and compositional structure of the upper mantle: global thermochemical models, Geophys. J. Int. Connolly, J. A. D. (2005), Computation of phase equilibria by linear programming: A tool for geodynamic modeling and its application to subduction zone decarbonation, Earth and

  11. Virtual button interface

    SciTech Connect

    Jones, J.S.

    1999-01-12

    An apparatus and method of issuing commands to a computer by a user interfacing with a virtual reality environment are disclosed. To issue a command, the user directs gaze at a virtual button within the virtual reality environment, causing a perceptible change in the virtual button, which then sends a command corresponding to the virtual button to the computer, optionally after a confirming action is performed by the user, such as depressing a thumb switch. 4 figs.

  12. Virtual button interface

    DOEpatents

    Jones, Jake S. (Albuquerque, NM)

    1999-01-01

    An apparatus and method of issuing commands to a computer by a user interfacing with a virtual reality environment. To issue a command, the user directs gaze at a virtual button within the virtual reality environment, causing a perceptible change in the virtual button, which then sends a command corresponding to the virtual button to the computer, optionally after a confirming action is performed by the user, such as depressing a thumb switch.

  13. Acoustic imaging microscope

    DOEpatents

    Deason, Vance A.; Telschow, Kenneth L.

    2006-10-17

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

  14. Ion photon emission microscope

    DOEpatents

    Doyle, Barney L. (Albuquerque, NM)

    2003-04-22

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

  15. Petrologic evidence for collisional heating of chondritic asteroids

    NASA Technical Reports Server (NTRS)

    Rubin, Alan E.

    1995-01-01

    The identification of the mechanism(s) responsible for heating asteroids is among the major problems in planetary science. Because of difficulties with models of electromagnetic induction and the decay of short-lived radionuclides, it is worthwhile to evaluate the evidence for collisional heating. New evidence for localized impact heating comes from the high proportion of relict type-6 material among impact-melt-bearing ordinary chondrites (OC). This relict material was probably metamorphosed by residual heat within large craters. Olivine aggregates composed of faceted crystals with 120 deg triple junctions occur within the melted regions of the Chico and Rose City OC melt rocks; the olivine aggregates formed from shocked, mosaicized olivine grains that underwent contact metamorphism. Large-scale collisional heating is supoorted by the correlation in OC between petrologic type and shock stage; no other heating mechanism can readily account for this correlation. The occurrence of impact-melt-rock clasts in OC that have been metamorphosed along with their whole rocks indicates that some impact events preceded or accompanied thermal metamorphism. Such impacts events, occurring during or shortly after accretion, are probably responsible for substantially melting approximately 0.5% of OC. These events must have heated a larger percentage of OC to subsolidus temperatures sufficient to have caused significant metamorphism. If collisional heating is viable, then OC parent asteroids must have been large; large OC asteroids in the main belt may include those of the S(IV) spectral subtype. Collisional heating is inconsistent with layered ('onion-shell') structures in OC asteroids (wherein the degree of metamorphism increases with depth), but the evidence for such structures is weak. It seems likely that collisional heating played an important role in metamorphosing chondritic asteroids.

  16. Petrology and Cosmochemistry of a Suite of R Chondrites

    NASA Technical Reports Server (NTRS)

    Torrano, Z. A.; Mittlefehldt, D. W.; Peng, Z. X.

    2015-01-01

    Chondrites are among the most primitive surviving materials from the early solar system. They are divided into groups based on chemical types defined by mineralogy, bulk composition, and oxygen isotope compositions. Chondrites range in petrographic grade from type 1 to type 7. Type 3 chondrites are the most primitive and are little changed from the nebular solids accreted to form asteroids. They are composed of chondrules, fine-grained matrix, metal and sulfide, plus or minus Ca-Al-rich inclusions. With increasing aqueous alteration at low temperatures, members of some chondrite classes transformed from type 3 towards type 1. With increasing thermal metamorphism and low fluid content, members of other classes changed from type 3 towards type 7. Rumuruti (R) chondrites are a rare group (0.1% of falls) similar to ordinary chondrites in some properties but different in others. They are characterized by low chondrule/matrix modal abundance ratios, high oxidation state, small mean chondrule size, abundant sulfides and low metal contents. R chondrites vary in petrologic type from 3 to 6. They are important objects to study because some of them have undergone metamorphism at high temperatures in the presence of aqueous fluids. In contrast, CM and CI chondrites were heated to low temperatures in the presence of aqueous fluids leading to alteration; they contain low-T hydrous phases (phyllosilicates) and little or no remaining metal. Ordinary chondrites were heated to high temperatures in a low-fluid environment resulting in anhydrous metamorphic rocks. R6 chondrites are highly metamorphosed and some contain the high-T hydrous phases mica and amphibole. R chondrites are thus unique and give us an opportunity to examine whether there are compositional effects caused by high-T, highfluid metamorphism of nebular materials.

  17. Scanning Electron Microscope - SEM

    NSDL National Science Digital Library

    This website is from Boston Museum of Science and is an introduction to Scanning Electron Micrscope (SEM). It contains an image gallery of insects, plants and other items as seen with an SEM. A slide show and a movie explains how the microsope works. Teacher resources offer guidance on building your own microscope and setting up a lab, including wet mounts and staining cells. Information on how the Museum uses the scope, and additional electronic resources, completes the site.

  18. Microscopic enteritis: Bucharest consensus.

    PubMed

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

    2015-03-01

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

  19. Electron microscope aperture system

    NASA Technical Reports Server (NTRS)

    Heinemann, K. (inventor)

    1976-01-01

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

  20. Microscopic Randomness and \\

    Microsoft Academic Search

    Heiko Lehmann

    1999-01-01

    \\u000a Starting from a continuous follow-the-leader model for individual vehicle motion a stochastic term is added in order to account for the elementary randomness of driving.\\u000a In a suitably defined stationary state thus an equilibrium distribution of nearest-neighbour distances is spanned up which\\u000a allows to understand the “fundamental diagram” of macroscopic traffic flow modelling as the ensemble average of the microscopic

  1. Q: How do Microscopes Work?

    ERIC Educational Resources Information Center

    Zimov, Sarah

    2004-01-01

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

  2. Parts of the Microscope and Their Function

    E-print Network

    Rose, Michael R.

    Parts of the Microscope and Their Function #12;Rules of using a microscope Always carry with 2 of the cords #12;Parts of a microscope #12;Parts of a microscope Eyepiece #12;Parts of a microscope Body tube #12;Parts of a microscope Nosepiece #12;Parts of a microscope Objectives Low power (short) High

  3. Virtual Goods Recommendations in Virtual Worlds

    PubMed Central

    Chen, Kuan-Yu; Liao, Hsiu-Yu; Chen, Jyun-Hung; Liu, Duen-Ren

    2015-01-01

    Virtual worlds (VWs) are computer-simulated environments which allow users to create their own virtual character as an avatar. With the rapidly growing user volume in VWs, platform providers launch virtual goods in haste and stampede users to increase sales revenue. However, the rapidity of development incurs virtual unrelated items which will be difficult to remarket. It not only wastes virtual global companies' intelligence resources, but also makes it difficult for users to find suitable virtual goods fit for their virtual home in daily virtual life. In the VWs, users decorate their houses, visit others' homes, create families, host parties, and so forth. Users establish their social life circles through these activities. This research proposes a novel virtual goods recommendation method based on these social interactions. The contact strength and contact influence result from interactions with social neighbors and influence users' buying intention. Our research highlights the importance of social interactions in virtual goods recommendation. The experiment's data were retrieved from an online VW platform, and the results show that the proposed method, considering social interactions and social life circle, has better performance than existing recommendation methods. PMID:25834837

  4. Modeling Engineering Change Management Process in Virtual

    E-print Network

    Akgunduz, Ali

    realityvirtual reality visualizationvisualization virtual enterprisevirtual enterprise interfaceinterface virtual realityvirtual reality visualizationvisualization virtual enterprisevirtual enterprise interfaceinterface virtual realityvirtual reality visualizationvisualization virtual realityvirtual reality

  5. Petrology and geochemistry of the Lyngdal granodiorite (Southern Norway) and the role of

    E-print Network

    Paris-Sud XI, Université de

    Petrology and geochemistry of the Lyngdal granodiorite (Southern Norway) and the role of fractional and trace elements, Sr­Nd isotopes) of the Lyngdal granodiorite and associated massifs (Tranevåg and Red correspond to the parent magma of the studied plutons. The Lyngdal granodiorite and associated massifs

  6. Author's personal copy Petrological evolution of silica-undersaturated sapphirine-bearing granulite in the

    E-print Network

    Nicollet, Christian

    Author's personal copy Petrological evolution of silica-undersaturated sapphirine-bearing granulite (c. 2.0 Ga). Well preserved in enclaves of silica- undersaturated sapphirine-bearing granulite occur in a charnockite outcrop located along a kilometric-scale shear zone. The sapphirine-bearing granulite preserves

  7. Sedimentary Petrology Field Trip to Gravel Quarry near Rotterdam Junction, NY

    NSDL National Science Digital Library

    Dr. Paul Ryberg

    This is a Stratigraphy Sedimentary Petrology field trip stop at an exceptional glacial outwash gravel quarry, where students measure, identify and count clast types, measure cross-bedding directions, and examine the early stages of lithification of gravel to conglomerate. The gravel deposits are also representative of the local surficial aquifer material that lies nearby in the subsurface.

  8. Petrologic monitoring of 1981 and 1982 eruptive products from Mount St. Helens

    Microsoft Academic Search

    K. V. CASHMAN; J. E. Taggard

    1983-01-01

    New material from the dacite lava dome of Mount St. Helens, collected soon after the start of each successive extrusion, is subjected to rapid chemical and petrologic analysis. The crystallinity of the dacite lava produced in 1981 and 1982 is 38 to 42 percent, about 10 percent higher than for products of the explosive 1980 eruptions. This increase in crystallinity

  9. Magnetic and petrologic characterization of synthetic Martian basalts and implications for the surface magnetization of Mars

    E-print Network

    Hammer, Julia Eve

    Magnetic and petrologic characterization of synthetic Martian basalts and implications for the surface magnetization of Mars Julie A. Bowles,1,2 Julia E. Hammer,1 and Stefanie A. Brachfeld3 Received 12 element composition, oxygen fugacity ( f O2), and cooling rate on phase chemistry and magnetic mineralogy

  10. Vic Camp Geol 688: Advanced Igneous Petrology Office: GMCS-228K

    E-print Network

    Camp, Vic

    exercises. We will examine the genesis of Igneous rocks through an understanding of phase diagramsVic Camp Geol 688: Advanced Igneous Petrology Fall 2009 Office: GMCS-228K Office hours: anytime to proceed in the following order: Nature of the upper mantle Ternary phase diagrams Processes in igneous

  11. PRELIMINARY RESULTS OF THE PETROLOGICAL-GEOCHEMICAL COMPONENT TO THE BATHOLITHS PROJECT

    E-print Network

    Wetmore, Paul H.

    during batholith generation. Petrologic and geochemical studies of arc-related, igneous and meta-igneous rocks along two proposed transects (Dean and Douglas Channels) will be carried out in this project generated from crustal and mantle-derived rocks, and (4) temporal changes in chemical and isotopic patterns

  12. Petrology of some oceanic island basalts: PRIMELT2.XLS software for primary magma calculation

    E-print Network

    Petrology of some oceanic island basalts: PRIMELT2.XLS software for primary magma calculation C, California 91125, USA [1] PRIMELT2.XLS software is introduced for calculating primary magma composition oxidation state, and clinopyroxene fractionation. Nevertheless, application of PRIMELT2.XLS to lavas from

  13. A new petrological and geophysical investigation of the present-day plumbing system of Mount Vesuvius

    Microsoft Academic Search

    A. Pommier; P. Tarits; S. Hautot; M. Pichavant; B. Scaillet; F. Gaillard

    2010-01-01

    A model of the electrical resistivity of Mt. Vesuvius has been elaborated to investigate the present structure of the volcanic edifice. The model is based on electrical conductivity measurements in the laboratory, on geophysical information, in particular, magnetotelluric (MT) data, and on petrological and geochemical constraints. Both 1-D and 3-D simulations explored the effect of depth, volume and resistivity of

  14. Petrology and Geochemistry of Lunar Meteorite Abar al'Uj 012

    NASA Astrophysics Data System (ADS)

    Mészáros, M.; Hofmann, B. A.; Korotev, R. L.; Gnos, E.; Greber, N.; Greenwood, R. C.

    2014-09-01

    The petrology and geochemistry of Abar al’Uj 012, a feldspathic lunar meteorite found in Saudi Arabia is described. The meteorite is a vesicular crystalline impact-melt breccia, which lacks a fusion crust and has a ferroan anorthosite affinity.

  15. "Geological Setting/Cadre Gologique" in English and French Petrology Articles: Muted Indications of Explored Places

    E-print Network

    Boyer, Edmond

    1997a: 362). Within this conceptualization, which has many points of contact with Critical Discourse to discourse community expectations. While these features have been widely investigated in numerous disciplines of petrological analysis, is a multi-functional description which frames researchers' results within

  16. Hardgrove grindability index and petrology used as an enhanced predictor of coal feed rate

    SciTech Connect

    Hower, J.C. (Univ. of Kentucky, KY (US))

    1990-01-01

    An improved predictor of coal pulverization behavior and coal feed rate is under development at the CAER based upon the interaction between Hardgrove Grindability Index (HGI) and coal petrology. With educated attention, this interaction may be a useful tool to enhance coal feed rates if cautiously extended to the mining environment where blends of coal lithotypes are produced.

  17. Thermal history of the Earth and its petrological expression Claude Herzberg a,

    E-print Network

    Earth, which may be why modern-day analogs of oceanic crust have not been reported in Archean greenstone belts. © 2010 Elsevier B.V. All rights reserved. 1. Introduction Earth's present-day magmatismThermal history of the Earth and its petrological expression Claude Herzberg a, , Kent Condie b

  18. Geochemical and petrological sampling and studies at the first moon base

    Microsoft Academic Search

    L. A. Haskin; R. L. Korotev; D. J. Lindstrom; M. M. Lindstrom

    1985-01-01

    Strategic sampling appropriate to the first-order lunar base can advance a variety of first-order lunar geochemical and petrological problems. Field observation and collection of samples would be done on the lunar surface, but detailed analysis would be done mainly in terrestrial laboratories. Among the most important areas of investigation for which field observations can be made and samples can be

  19. Deep crustal structure beneath large igneous provinces and the petrologic evolution of flood basalts

    Microsoft Academic Search

    Victoria A. Ridley; Mark A. Richards

    2010-01-01

    We present a review of seismological constraints on deep crustal structures underlying large igneous provinces (LIPs), largely from wide-angle seismic refraction surveys. The main purpose of this review is to ascertain whether this seismic evidence is consistent with, or contrary to, petrological models for the genesis of flood basalt lavas. Where high-quality data are available beneath continental flood basalt (CFB)

  20. Unmixing the SNCs: Chemical, Isotopic, and Petrologic Components of the Martian Meteorites

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This volume contains abstracts that have been accepted for presentation at the conference on Unmixing the SNCs: Chemical, Isotopic, and Petrologic Components of Martian Meteorites, September 11-12, 2002, in Houston, Texas. Administration and publications support for this meeting were provided by the staff of the Publications and Program Services Department at the Lunar and Planetary Institute.

  1. 1992 Research Highlights 1 . NanoManipulator--A Virtual Reality Interface for Interactive Control

    E-print Network

    North Carolina at Chapel Hill, University of

    -feedback interface for scanning tunneling microscopes, atomic force microscopes, etc. The chemist uses a head, especially the lighting angle, on the surface. The effect is to scale the chemist down by about 108, put him is designed to let a chemist deform virtual protein molecules interactively, while the molecules continue

  2. ARTIGO INTERNET IST lana plataforma virtual Visita Virtual ao Campus

    E-print Network

    Instituto de Sistemas e Robotica

    NewsSearch ARTIGO INTERNET IST lança plataforma virtual Visita Virtual ao Campus in http://www.briefing.pt/ Data: 2011-7-7 Link: http://www.briefing.pt/index.p ... IST lança plataforma virtual Visita Virtual ao

  3. Scanning Electron Microscope

    NSDL National Science Digital Library

    1998-01-01

    As part of the Science Learning Network, the Scanning Electron Microscope (SEM) Web site explores what an SEM is, how it's used, and what images it can produce. The How It Works section has a self-paced tutorial and an interesting movie describing how it functions as well. The other section for students is the image gallery, which has the Animal, Vegetable, Mineral game. Individual images from a SEM are shown, and users get to guess which of the three substances is shown. It isn't as easy as it sounds, but it is fun.

  4. Low frequency acoustic microscope

    DOEpatents

    Khuri-Yakub, Butrus T. (Palo Alto, CA)

    1986-11-04

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

  5. Idea Bank: Microscopic Impressionism

    NSDL National Science Digital Library

    John Reitnauer

    2005-04-01

    Claude Monet meets the world of science through Histro-Art, a concept that was conceived from the impressions of an 11th and 12th-grade college preparatory human anatomy and physiology class who were studying histology using a micro-video system. As they observed a slide of smooth muscle, one student noticed the resemblance to impressionist art, and thus the concept was born. In this engaging activity, students observe microscopic slide tissue and interpret impressionism theory using various mediums to create their own art pieces. It is sure to leave them with a lasting "impression" of the connection between art and science.

  6. Atomic Force Microscope

    SciTech Connect

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

    1988-12-01

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

  7. Petrology of enstatite chondrites and anomalous enstatite achondrites

    NASA Astrophysics Data System (ADS)

    van Niekerk, Deon

    2012-01-01

    Chondrites are meteorites that represent unmelted portions of asteroids. The enstatite chondrites are one class of chondrites. They consist of reduced mineral assemblages that formed under low oxygen fugacity in the solar nebula, prior to accretion into asteroids. There are two groups of enstatite chondrites---EH and EL. I studied EL3 meteorites, which are understood to be unmetamorphosed and thus to only preserve primitive nebular products. I show in a petrographic study that the EL3s are in fact melt--breccias in which impact-melting produced new mineral assemblages and textures in portions of the host chondrites, after accretion. I document meta- land sulfide assemblages that are intergrown with silicate minerals (which are often euhedral), and occur outside chondrules; these assemblages probably represent impact-melting products, and are different from those in EH3 chondrites that probably represent nebular products. In situ siderophile trace element compositions of the metal in EL3s, obtained by laser ablation inductively coupled plasma mass spectrometry, are consistent with an impact-melting hypothesis. The trace element concentrations show no clear volatility trend, and are thus probably not the result of volatile-driven petrogenetic processes that operated in the solar nebula. Trace element modeling suggests that the character of the trace element patterns together with deviations from the mean bulk EL metal pattern is consistent with metal that crystallized in a coexisting liquid-solid metal system in which dissolved carbon influenced element partitioning. I also conducted a petrographic and mineral-chemistry study of several anomalous enstatite meteorites. These have igneous textures, but unfractionated mineralogy similar to unmelted chondrites. I show that with the exception of one, the meteorites are related to each other, and probably formed by crystallization from an impact melt instead of metamorphism through the decay of short lived radionuclides. The broad importance of these studies lies in documenting the petrology of extraterrestrial materials that reveal the geological history of the young solar system prior to the existence of planets. Furthermore, they serve to identify which mineral assemblages record nebular processes and which record processes on asteroids, so that future studies may select the correct material to address particular questions.

  8. Petrology of the Betulia Igneous Complex, Cauca, Colombia

    NASA Astrophysics Data System (ADS)

    Gil-Rodriguez, Javier

    2014-12-01

    The Betulia Igneous Complex (BIC) is a group of Late-Miocene (11.8 ± 0.2 Ma) hypabyssal intrusions of intermediate to felsic composition located in the SW of the Colombian Andes. These bodies have a calc-alkaline tendency and are related to the subduction of the Nazca plate under the South American plate. Diorites, quartz diorites and tonalities have porphyritic and phaneritic textures and are composed of plagioclase, amphibole, quartz, biotite, and orthoclase. Plagioclase is mainly of andesine-type and the amphiboles were classified mainly as magnesiohornblendes, actinolites, and tschermakites. BIC rocks have a narrow range of SiO2 content (59-67wt%) and exhibit an enrichment of LILE and LREE relative to HFSE and HREE, respectively. These features are attributed to enrichment of LILE from the source and retention of HFSE (mainly Nb, Ta, and Ti) by refractory phases within the same source. The depletion of HREE is explained by fractionation of mineral phases that have a high partition coefficients for these elements, especially amphiboles, the major mafic phase in the rocks. Nevertheless, the fractionation of garnet in early stages of crystallization is not unlikely. Probably all BIC units were generated by the same magma chamber or at least by the same petrologic mechanism as shown by the similar patterns in spider and REE diagrams; fractional crystallization and differentiation processes controlled the final composition of the rocks, and crystallization stages determined the texture. Isotopic compositions of BIC rocks (87Sr/86Sr: 0.70435-0.70511; 143Nd/144Nd: 0.51258-0.51280; 206Pb/204Pb: 19.13-19.31; 207Pb/204Pb: 15.67-15.76; 208Pb/204Pb: 38.93-39.20) indicate a source derived from the mantle with crustal contamination. The model proposed for the BIC consists of fluids from the dehydration of the subducted slab (Nazca plate) and subducted sediments that generated partial melting of the mantle wedge. These basaltic melts ascended to the mantle-crust boundary where they were retained due to density differences and began to produce processes of melting, assimilation, storage, and homogenization (MASH zone). At this depth (?40-45 km), fractional crystallization and differentiation processes began to produce more felsic magmas that were able to ascend through the crust and be emplaced at shallow depths.

  9. On the Grand Challenges in Physical Petrology: the Multiphase Crossroads

    NASA Astrophysics Data System (ADS)

    Bergantz, G. W.

    2014-12-01

    Rapid progress in experimental, micro-analytical and textural analysis at the crystal scale has produced an unprecedented record of magmatic processes. However an obstacle to further progress is the lack of understanding of how mass, energy and momentum flux associated with crystal-rich, open-system events produces identifiable outcomes. Hence developing a physically-based understanding of magmatic systems linking micro-scale petrological observations with a physical template operating at the macro-scale presents a so-called "Grand Challenge." The essence of this challenge is that magmatic systems have characteristic length and feedback scales between those accessible by classical continuum and discrete methods. It has become increasingly obvious that the old-school continuum methods have limited resolution and power of explanation for multiphase (real) magma dynamics. This is, in part, because in crystal-rich systems the deformation is non-affine, and so the concept of constitutive behavior is less applicable and likely not even relevant, especially if one is interested in the emergent character of micro-scale processes. One expression of this is the cottage industry of proposing viscosity laws for magmas, which serves as "blunt force" de facto corrections for what is intrinsically multiphase behavior. Even in more fluid-rich systems many of these laws are not suitable for use in the very transport theories they aim to support. The alternative approach is the discrete method, where multiphase interactions are explicitly resolved. This is a daunting prospect given the numbers of crystals in magmas. But perhaps all crystals don't need to be modeled. I will demonstrate how discrete methods can recover critical state behavior, resolve crystal migration, the onset of visco-elastic behavior such as melt-present shear bands which sets the large-scale mixing volumes, some of the general morpho-dynamics that underlies purported rheological models, and transient controls on the emergence and dissipation of distinct thermodynamic states. As simulations with 106 - 107 crystals are now possible both the local, micro-scale crystal processes as well as the larger scale processes controlled by particle-particle-fluid interactions, can be simultaneously resolved.

  10. Electron microscope phase enhancement

    DOEpatents

    Jin, Jian; Glaeser, Robert M.

    2010-06-15

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

  11. Exploratorium: Microscope Imaging Station

    NSDL National Science Digital Library

    In the summer of 2004, the Exploratorium museum in San Francisco unveiled their very ambitious and interesting microscope facility. Over the past few years they've spent a considerable amount of time and money on this project, and they've also created this fine website to offer those far away from the Bay area some access to this project. First-time visitors will want to click on the "Features" area to get started. Here they can look at the cells of sea urchins, blood, zebrafish, and frogs. Each feature has images of the cells, along with complete background material on the work that is being done through the use of these high-powered images. The "Gallery" is a great place to stop next, as it contains dozens of high-resolution images and movies created with research-grade microscopes. Here visitors can learn about cell motility, development, and immune response through looking over this extensive gallery that covers the gamut of different cellular activities. Finally, the site also contains an "Activities" area that includes classroom activities, printable flipbooks, and desktop wallpaper.

  12. Scanning Electron Microscope Room

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This image shows a scanning electron microscope (SEM). This instrument uses a highly-focused beam of electrons to provide visual images of the surface of materials at magnifications up to 20,000X or more. These high magnification images allow the researcher to identify details about the material's microstructure, such as the types and sizes of microscopic particles present. The beam of electrons can also be used to examine volumes (as small as 1 micrometer in diameter) of the material being analyzed to provide information about the chemistry. This information can be used to determine chemical variations as a function of location within the material's microstructure, as well as the chemical composition of individual particles. In addition, the SEM is equipped with sophisticated instrumentation that can determine the crystal structure of individual grains and how each grain is oriented with respect to neighboring grains within the material. The chemistry and crystal structure information can be related to fracture behavior and used to modify the manufacturing processes used to produce the material in order to improve its properties.

  13. Realistic virtual hand modeling with applications for virtual grasping

    Microsoft Academic Search

    Huagen Wan; Yang Luo; Shuming Gao; Qunsheng Peng

    2004-01-01

    In virtual environments, virtual hand interactions play key roles in the human-computer interface. Specifically, the virtual grasping of 3D objects provides an intuitive way for users to interact with virtual objects. This paper demonstrates the creation of a sophisticated virtual hand model simulating natural anatomy in its appearance and motion. To achieve good visual realism, the virtual hand is modeled

  14. L19 Virtual Memory 1Comp 411 Virtual Memory

    E-print Network

    Bishop, Gary

    table #12;L19 ­ Virtual Memory 16Comp 411 Which block is replaced on miss? Direct mapped cache haveL19 ­ Virtual Memory 1Comp 411 Virtual Memory Carolina Course Evaluation Open Today: Virtual Memory #12;L19 ­ Virtual Memory 2Comp 411 Virtual Memory ·Main memory is a CACHE for disk ·Advantages

  15. Organic petrological and organic geochemical characterisation of the Tertiary coal-bearing sequence of Batu Arang, Selangor, Malaysia

    NASA Astrophysics Data System (ADS)

    Wan Hasiah, Abdullah; Abolins, Peter

    1998-08-01

    The Tertiary coal-bearing sequence at Batu Arang in Selangor, Peninsular Malaysia consists of a sandstone-coal-oil shale facies assemblage. A detailed organic petrological and organic geochemical study was carried out on several organic-rich sediments from this sequence. The oil shales are dominated by Botryococcus-derived telalginite and Pediastrum-derived lamalginite. The coals, hypautochthonous in origin, are mainly duroclarite-type, although other minor microlithotypes also occur. Alginite is not observed in the coals, but other liptinitic constituents are very common, particularly thin-walled cutinite and sporinite. The oil shales and the coals are thermally immature. This immaturity has a considerable influence on the biomarker distributions, particularly so on the triterpanes which are dominated by C 31?? 22R and C 30?? compounds. Interestingly, for Tertiary aged sediments of continental origin, the diagnostic biomarker compounds such as 18 ?(H)-oleanane and bicadinanes, normally linked to the higher land plant group of angiosperms, are not observed in the samples analysed. Tricyclic terpanes occur only in very low relative abundance or are virtually absent. A clear distinction, however, in the biomarker distributions of the shales and the coals/carbargilite can be made based upon the distribution of C 27-C 29 regular steranes: the shales, with a source input being predominantly planktonic algae, are dominated by 5 ?(H),14 ?(H),17 ?(H) 20R cholestane, while the coals/carbargilites, with a source input consisting mainly of higher plant material, are dominated by 5 ?(H),14 ?(H),17 ?(H) 20R ethyl cholestane. The depositional environment of the Batu Arang coal-bearing sequence is interpreted as varying from an alluvial flood plain peat-swamp to fluvio-lacustrine depositional setting.

  16. Autonomous Virtual Mobile Nodes

    E-print Network

    Dolev, Shlomi

    2005-06-15

    This paper presents a new abstraction for virtual infrastructure in mobile ad hoc networks. An AutonomousVirtual Mobile Node (AVMN) is a robust and reliable entity that is designed to cope with theinherent difficulties ...

  17. HHMI: Virtual Neurophysiology Lab

    NSDL National Science Digital Library

    HHMI (Howard Hughes Medical Institute)

    2012-12-01

    This Virtual Lab provides students the opportunity to explore the electrical activity of individual neurons by virtually stimulating the skin of a leech. A lab notebook, equipment list, atlas of cells and recordings is provided to simulate a lab activity.

  18. Interactive stereo electron microscopy enhanced with virtual reality

    Microsoft Academic Search

    E. Wes Bethel; S. Jacob Bastacky; Kenneth S. Schwartz

    2001-01-01

    An analytical system is presented that is used to take measurements of objects perceived in stereo image pairs obtained from a scanning electron microscope (SEM). Our system operates by presenting a single stereo view that contains stereo image data obtained from the SEM, along with geometric representations of two types of virtual measurement instruments, a ''protractor'' and a ''caliper''. The

  19. Interactive stereo electron microscopy enhanced with virtual reality

    Microsoft Academic Search

    E. W. Bethel; S. J. Bastacky; Ken Schwartz

    2002-01-01

    An analytical system is presented that is used to take measurements of objects perceived in stereo image pairs obtained from a scanning electron microscope (SEM). Our system operates by presenting a single stereo view that contains stereo image data obtained form the SEM, along with geometric representations of two types of virtual measurement instruments, a protractor and a caliper. The

  20. The Virtual Tricorder

    Microsoft Academic Search

    Matthias M. Wloka; Eliot Greenfield

    We describe a new user-interface metaphor for immersive virtual reality — the virtual tricorder (named for the Star Trek devi ce). The virtual tricorder visually duplicates an actual six-de grees-of- freedom input device in the virtual environment. Since we map the input device to the tricorder one-to-one at all times, th e user identifies the two. Thus, the resulting interface

  1. MIL 07687 — An Intriguing, Very Low Petrologic Type 3 Carbonaceous Chondrite with a Unique Style of Aqueous Alteration

    NASA Astrophysics Data System (ADS)

    Brearley, A. J.

    2012-03-01

    MIL 07687 is a unique low petrologic type carbonaceous chondrite with a very high abundance of matrix (~68 wt%) and unusual style of alteration. Chondrules contain primary glass, but matrix has been extensively replaced by a fibrous Fe-oxyhydroxide.

  2. Virtual Reality: An Overview.

    ERIC Educational Resources Information Center

    Franchi, Jorge

    1994-01-01

    Highlights of this overview of virtual reality include optics; interface devices; virtual worlds; potential applications, including medicine and archaeology; problems, including costs; current research and development; future possibilities; and a listing of vendors and suppliers of virtual reality products. (Contains 11 references.) (LRW)

  3. Virtual Reference Services.

    ERIC Educational Resources Information Center

    Brewer, Sally

    2003-01-01

    As the need to access information increases, school librarians must create virtual libraries. Linked to reliable reference resources, the virtual library extends the physical collection and library hours and lets students learn to use Web-based resources in a protected learning environment. The growing number of virtual schools increases the need…

  4. Exploring virtual ecosystems

    Microsoft Academic Search

    Antão Vaz Almada; António Eduardo Dias; João Pedro Silva; Emanuel Marques dos Santos; Pedro José Pedrosa; António Sousa Câmara

    1996-01-01

    Browsing In Time & Space (BITS) is an interface designed to explore virtual ecosystems. A virtual ecosystem includes a three dimensional terrain model background, collections of man-made and natural objects, and behavior and interaction rules between the objects and the background. BITS is based on a virtual notepad and pen metaphor and is inspired in the concept of logging. Physical

  5. What is virtual instrumentation?

    Microsoft Academic Search

    H. Goldberg

    2000-01-01

    A virtual instrument is composed of some specialized subunits, some general-purpose computers, some software, and a little know-how. The instrument no longer has to be in one box. Virtual instruments can be simple or very complex. Understanding the real field of virtual instrumentation is just beginning. Over the next few years, there will be a rash of subunits specifically designed

  6. Femtosecond photoelectron point projection microscope

    SciTech Connect

    Quinonez, Erik; Handali, Jonathan; Barwick, Brett [Department of Physics, Trinity College, 300 Summit St., Hartford, Connecticut 06106 (United States)] [Department of Physics, Trinity College, 300 Summit St., Hartford, Connecticut 06106 (United States)

    2013-10-15

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

  7. Femtosecond photoelectron point projection microscope.

    PubMed

    Quinonez, Erik; Handali, Jonathan; Barwick, Brett

    2013-10-01

    By utilizing a nanometer ultrafast electron source in a point projection microscope we demonstrate that images of nanoparticles with spatial resolutions of the order of 100 nanometers can be obtained. The duration of the emission process of the photoemitted electrons used to make images is shown to be of the order of 100 fs using an autocorrelation technique. The compact geometry of this photoelectron point projection microscope does not preclude its use as a simple ultrafast electron microscope, and we use simple analytic models to estimate temporal resolutions that can be expected when using it as a pump-probe ultrafast electron microscope. These models show a significant increase in temporal resolution when comparing to ultrafast electron microscopes based on conventional designs. We also model the microscopes spectroscopic abilities to capture ultrafast phenomena such as the photon induced near field effect. PMID:24182122

  8. Mars Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

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

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

  9. A petrologic and mechanical analysis of the Lion Mountain and Welge sandstones of southern Mason County, Texas 

    E-print Network

    Daugherty, Thomas Daniel

    1960-01-01

    A PETROLOGIC AND MECHANICAL ANALYSIS OF THE LION MOUNTAIN AND WELGE SANDSTONES OF SOUTHERN MASON COUNTY, TEXAS By Thomas Daniel Daugherty Submitted to the Graduate School of the Agrtcultural and Mechanical College of Texas in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE in Geology January, 1960 A PETROLOGIC AND MECHANICAL ANALYSIS OF THE LION MOUNTAIN AND WELGE SANDSTONES OF SOUTHERN MASON COUNTY, TEXAS A Thesis by Thomas Daniel Daugherty January...

  10. Petrology, diagnosis, and sedimentology of oil reservoirs in Upper Cretaceous Shannon Sandstone Beds, Powder River basin, Wyoming

    SciTech Connect

    Hansley, P.L.; Whitney, C.G.

    1990-01-01

    This paper reports on a study of the petrology of the Shannon Sandstone Member that indicates diagenetic alterations of outcrop and near-surface sandstones cannot be used to predict the diagenesis of deeply buried sandstones. Textural relations show that oil migrated to reservoirs late in the postdepositional history of the Shannon. Petrologic and sedimentologic data suggest that an alternative depositional model (for example, a nearshore rather than mid-shelf setting) should be considered for the Shannon.

  11. Metrological scanning probe microscope

    NASA Astrophysics Data System (ADS)

    Dorozhovets, N.; Hausotte, T.; Manske, E.; Jäger, G.; Hofmann, N.

    2006-04-01

    Today's technological progress calls for metrologically accurate object measurement, positioning and scanning with nanometre precision and over large measuring ranges. In order to meet that requirement a nanopositioning and nanomeasuring machine (NPM machine) was developed at the Institute of Process Measurement and Sensor Technology of the Technische Universitaet Ilmenau. This device is capable of highly exact long-range positioning and measurement of objects with a resolution of less than 0.1 nm. Due to the structure of the machine many different probe systems can be installed, including scanning probe microscopes (SPMs). A few SPMs have outstanding metrological characteristics and many commercial microscopes only perform as image acquisition tools. Commercial SPMs use piezoelectric actuators in order to move either the sample or the probe. The position measurement sometimes results from the applied voltage to the piezoelectric actuators or from the strain gauge or capacitive displacement sensor data. This means that they suffer from hysteresis, creep, nonlinear characteristics and Abbe offsets. For an accurate measurement the position of the cantilever must be measured in addition to the torsion and bending. The best solution is a combined detection system with a single laser beam. This system has been realized with a special interferometer system, in which the measuring beam is focused on the cantilever backside using a lens. The reflected beam is split with a part being detected by a quadrant photo-diode and the other part being fed back into the interferometer for position measurement. The quadrant photo-diode is used to detect the cantilever torsion and bending.

  12. Atomic Force Microscope Operation

    NASA Technical Reports Server (NTRS)

    2008-01-01

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

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

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

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

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

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

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

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

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

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

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

  13. The Virtual Ocean

    NSDL National Science Digital Library

    Wim van Egmond

    2007-12-12

    At this site, students examine larve, crustaceans, algae, and other microscopic organisms that inhabit the oceans. The site provides exceptional images and basic information about the organism's anatomy and development. There are also links to sites about freshwater microscopic organisms.

  14. Magmatic plumbing of Mount St. Helens - petrologic insights

    NASA Astrophysics Data System (ADS)

    Pallister, J. S.; Cashman, K.; Thornber, C.; Dzurisin, D.; Hoblitt, R.; Myers, B.; Linscott, J.; Lowers, H.; Brownfield, I.; Plumlee, G.; Meeker, G.; Wright, H.; Reagan, M.; Rowe, M.; Vallance, J.; Gardner, C.; Scott, W.

    2004-12-01

    Monitoring of the current eruption of Mount St. Helens has posed fundamental questions about the magmatic plumbing system and the source of new dome magma. At the time of this writing (10-24-04) a new lava dome is forming south of the 1980-1986 dome. A primary question, with important implications for volcano hazards, is whether shallow (<4 km) magma stored in the conduit is driving dome extrusion, or whether the ultimate driving force is rise of deep (>6 km) gas-rich magma. Geophysical data from the past month record upward movement of magma at shallow levels (<2 km), but have not revealed deeper processes. Following uplift of the southern margin of the 1980-1986 lava dome and adjacent glacier in late September, vigorous steam and ash emissions commenced on October 1 and continued through October 5. Ash from early emissions contains mainly non-juvenile mineral grains, pumice, and lithic fragments derived from older MSH deposits in the crater floor, yet leachates from these deposits and excesses in the short-lived isotope 210Po indicate fluxing by magmatic gases. On October 11, observers noted a spine of dacite rising from the NW margin of the uplift. By October 20, when the first juvenile rock samples were collected by helicopter, a wall of hot dacite (maximum FLIR remperature 700ºC) had been extruded and the volume of uplift had grown to >10 million m3. Most of the juvenile lava is cpx-bearing hy-hb dacite with thick coarse-grained reaction rims on hornblende and a devitrified groundmass with interstitial quartz, indicative of very low pressure (<1 km depth) crystallization. A subordinate component has more abundant groundmass glass, thin reaction rims on hornblende, finer-grained matrix crystals and yields Fe-Ti oxide temperatures of 900ºC at fO2=10-11), similar to the May 18, 1980 magma. Ash emitted from the crater since the first emergence of the spine also contains abundant juvenile dacite fragments with swallowtail microphenocrysts (30-50 µm) similar to those in some post-May 18, 1980 pyroclasts and dome lavas and suggesting decompression and gas loss at very shallow levels. These petrologic features indicate that the 2004 magma includes at least two components: viscous degassed magma uplifted as spines from shallow levels of the conduit, and hot, lower-viscosity dacite that was transported rapidly from depth, possibly forming dikes within the spine magma and helping lubricate its ascent. Derivation of magma from shallow levels of the conduit system is consistent with generally low and intermittant CO2 and SO2 emissions, which likely track arrival of small batches of hotter and less degassed magma from depth. We suggest that the seismic, deformation and gas monitoring data recorded to date are consistent with a model in which viscous magma from shallow levels of the conduit is being pushed up and out of the 1980-86 conduit, but that ascent of this magma is enabled by more rapid ascent of hotter and more gas-rich magma from a deeper reservoir.

  15. Quantitative and Qualitative Changes in Teaching Histology by Means of Virtual Microscopy In an Introductory Course in Human Anatomy

    NSDL National Science Digital Library

    Polly Husmann (Indiana University School of Medicine Medical Sciences Program)

    2009-09-14

    This article describes a study investigating the learning impact of using virtual microscopy versus the tradition optical microscope in an undergraduate anatomy course. The study used lab averages, individual test scores, and survey results to compare differences.

  16. Video: Focusing a Compound Microscope

    NSDL National Science Digital Library

    This video from CUNY Kingsborough Community College describes how to focus a compound microscope. The brief clip, available for viewing on YouTube, would be most useful for students with a basic understanding of the parts of a compound microscope and how to use it. Running time for the video is 0:55.

  17. The Latest in Handheld Microscopes

    ERIC Educational Resources Information Center

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

    2004-01-01

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

  18. Using the Microscope: Basic Tutorial

    NSDL National Science Digital Library

    Micrographia (Micrographia)

    2012-01-06

    This tutorial is for those whose work involves day-to-day use of the light microscope, as well as those approaching the instrument for the first time. The intention is to pass on sufficient information that microscope users may better understand their instrument, set it up in a way that produces a satisfactory image in a comfortable setting, and proceed with their work.

  19. Mineralogy, petrology and chemistry of ANT-suite rocks from the lunar highlands

    NASA Technical Reports Server (NTRS)

    Prinz, M.; Keil, K.

    1977-01-01

    Anorthositic-noritic-troctolitic (ANT) rocks are the oldest and most abundant rocks of the lunar surface, and comprise about 90% of the suite of the lunar highlands. Consideration is given to the mineralogy, petrology, bulk chemistry, and origin of ANT-suite rocks. Problems associated in classifying and labeling lunar highland rocks because of textural complexities occurring from impact modifications are discussed. The mineralogy of ANT-suite rocks, dominated by plagioclase, olivine and pyrozene, and containing various minor minerals, is outlined. The petrology of ANT-suite rocks is reviewed along with the major element bulk composition of these rocks, noting that they are extremely depleted in K2O and P2O5. Various models describing the origin of ANT-suite rocks are summarized, and it is suggested that this origin involves a parental liquid of high-alumina basalt with low Fe/Fe+Mg.

  20. Constraints on chondrule origin from petrology of isotopically characterized chondrules in the Allende meteorite

    SciTech Connect

    Mcsween, H.Y. Jr.

    1985-09-01

    The petrologic and chemical properties of the ferromagnesian chondrules in the Allende carbonaceous chondrite were examined in terms of the isotopic composition and the correlations between isotopic patterns. Areas of thin sections were studied with a SEM and bulk chemical fractions of 12 constituents were quantified to calculate correlations with petrologic features. A possible correlation between (CaO + Al2O2)/MgO and oxygen isotopes imply the formation of oxygen isotopic compositions in the chondrules by exchanges between isotopically heavy nebular gases and O-16 enriched solids. Different rates of gaseous exchange occurred with the various types of chondrules. Factors which may have controlled the exchanges are discussed. 21 references.

  1. Fractal approach in petrology: Small-angle neutron scattering experiments with volcanic rocks

    SciTech Connect

    Lucido, G.; Triolo, R.; Caponetti, E.

    1988-11-01

    Following Mandelbrot's pioneering work in 1977, we attempt to use the concept of fractal dimension in petrology. Fractal dimension is an intensive property of matter which offers a quantitative measure of the degree of surface roughness. Neutron scattering experiments have been performed on 18 volcanic rocks from different localities. The scattered intensity as a function of the momentum transfer obeys a power law whose exponent varies, for the rock samples presented, between -3 and -4. We conclude that, at the molecular level, our volcanic rocks are not fractal volumes. With regard to the particle-matrix interface, it is not possible to provide a determination at the present stage of research. Our findings suggest it is feasible to verify the degree of surface irregularity at a resolution which is relevant to many aspects of petrology.

  2. MinChem: A Prototype Petrologic Database for Hanford Site Sediments

    SciTech Connect

    Mackley, Rob D.; Last, George V.; Serkowski, John A.; Middleton, Lisa A.; Cantrell, Kirk J.

    2010-09-01

    A prototype petrologic database (MinChem) has been under continual development for several years. MinChem contains petrologic, mineralogical, and bulk-rock geochemical data for Hanford Site sediments collected over multiple decades. The database is in relational form and consists of a series of related tables modeled after the Hanford Environmental Information System HEIS (BHI 2002) structures. The HEIS-compatible tables were created in anticipation of eventual migration into HEIS, or some future form of HEIS (e.g. HEIS-GEO). There are currently a total of 13,129 results in MinChem from 521 samples collected at 381 different sampling sites. These data come from 19 different original source documents published and unpublished (e.g. letter reports) between 1976 and 2009. The data in MinChem consist of results from analytical methods such as optical and electron microscopy, x-ray diffraction, x-ray fluorescence, and electron probe microanalysis.

  3. Mueller matrix microscopic ellipsometer

    NASA Astrophysics Data System (ADS)

    Otsuki, Soichi; Murase, Norio; Kano, Hiroshi

    2013-09-01

    We propose a Mueller matrix ellipsometer based on imaging of the exit pupil of a microscope objective lens. The instrument had a polarizer and a rotating phase retarder on the polarizing arm and a polarizer (analyzer) on the analyzing arm. A vector F representing the optical effect from the objective lens to the detector was obtained by rotating the retarder and analyzing the CCD images taken at multiple azimuths of the retarder. Twelve elements of the Mueller matrix of the sample were determined from the four elements of the F vector. To test this method, a thin film on a cover glass was measured using an oil-immersion objective on internal reflection geometry. The refractive index and thickness of the film were well fitted to a three layer model taking into account the contributions of the objective effect. The accuracy of this system was also evaluated using matrix elements ideally equal to 0 or 1. The random error was estimated from the measured images of the F vector elements to be approximately 0.1% at maximum. The sources of the random and systematic errors inherent to this system were also discussed.

  4. Understanding the virtuality of virtual organizations

    Microsoft Academic Search

    Sandhya Shekhar

    2006-01-01

    Purpose – The virtual organization is emerging as a much-researched phenomenon in the context of inter-organizational relationships as well as intra-organizational issues. However, the existing literature on the subject provides multifarious views of virtual organizations, making it difficult to compare findings in research and derive actionable inputs for practice. This paper proposes a multi-dimensional model with nine possible variants that

  5. Correlation of seismic and petrologic thermometers suggests deep thermal anomalies beneath hotspots

    Microsoft Academic Search

    Anna M. Courtier; Matthew G. Jackson; Jesse F. Lawrence; Zhengrong Wang; Cin-Ty Aeolus Lee; Ralf Halama; Jessica M. Warren; Rhea Workman; Wenbo Xu; Marc M. Hirschmann; Angela M. Larson; Stan R. Hart; Carolina Lithgow-Bertelloni; Lars Stixrude; Wang-Ping Chen

    2007-01-01

    A fundamental question regarding the dynamics of mantle convection is whether some intraplate volcanic centers, known as “hotspots,” are the surface manifestations of hot, narrow, thermally driven upwellings, or plumes, rising from the lower mantle. Shown here is a global negative correlation between the thickness of the mantle transition zone (near 410–660 km depth) and petrologically determined potential temperatures of mid-ocean

  6. Petrology/Geochemistry/Mineralogy/Structure of Shear zones in St. Lawrence County

    NSDL National Science Digital Library

    Robert Badger

    These rocks were collected from outcrops frequented by structural geology field trips. CCM 42 is from the town of Clare, CCM 43 is from Russell; although labeled CCM, neither is from the Carthoage Colton Mylonite Zone, but both are from shear zones. DEK is from the world famous DeKalb anticline. In this lab we try to pull together material from petrology, geochemistry, mineralogy and structure.

  7. Research in volcanic geology, petrology and planetary science at MIT, 1969 to 1974

    NASA Technical Reports Server (NTRS)

    Mcgetchin, T. R.

    1974-01-01

    The behavior of volcanoes was studied by geologic mapping, petrologic investigations of lava and xenoliths, physical measurements, and theoretical modelling. Field observations were conducted in Alaska (Nunivak Island), Iceland, Hawaii (Mauna Kea), Italy (Etna, Stromboli), and Arizona. The results are discussed and compared with known data for lunar and planetary gelogy. Field methods used for the volcano research are cited and a list is given of all participating scientists and students. Publications and abstracts resulting from the research are also listed.

  8. Petrology and Tectonics of the Derewo Metamorphic Belt, West New Guinea

    Microsoft Academic Search

    Paul Q. Warren; Mark Cloos

    2007-01-01

    The Derewo Metamorphic Belt (also known as the Ruffaer Metamorphic Belt) is a >500 km long, narrow (~10-30 km wide), roughly E-W-trending terrane composed mostly of slate and phyllite, on the northern flank of the Central Range of Papua, Indonesia (west New Guinea). This investigation, the first systematic petrologic study of the belt, is based on petrographic and mineral chemical

  9. Thermal and petrologic constraints on the lower crustal melt accumulation in the Salton Sea Geothermal Field

    NASA Astrophysics Data System (ADS)

    Karakas, O.; Dufek, J.; Mangan, M.; Wright, H. M. N.

    2014-12-01

    Heat transfer in active volcanic areas is governed by complex coupling between tectonic and magmatic processes. These two processes provide unique imprints on the petrologic and thermal evolution of magma by controlling the geometry, depth, longevity, composition, and fraction of melt in the crust. The active volcanism, tectonic extension, and significantly high surface heat flow in Salton Sea Geothermal Field, CA, provides information about the dynamic heat transfer processes in its crust. The volcanism in the area is associated with tectonic extension over the last 500 ka, followed by subsidence and sedimentation at the surface level and dike emplacement in the lower crust. Although significant progress has been made describing the tectonic evolution and petrology of the erupted products of the Salton Buttes, their coupled control on the crustal heat transfer and feedback on the melt evolution remain unclear. To address these concepts, we develop a two-dimensional finite volume model and investigate the compositional and thermal evolution of the melt and crust in the Salton Sea Geothermal Field through a one-way coupled thermal model that accounts for tectonic extension, lower crustal magma emplacement, sedimentation, and subsidence. Through our simulations, we give quantitative estimates to the thermal and compositional evolution and longevity of the lower crustal melt source in the crustal section. We further compare the model results with petrologic constraints. Our thermal balance equations show that crustal melting is limited and the melt is dominated by mantle-derived material. Similarly, petrologic work on ?18O isotope ratios suggests fractional crystallization of basalt with minor crustal assimilation. In addition, we suggest scenarios for the melt fraction, composition, enthalpy release, geometry and depth of magma reservoirs, their temporal evolution, and the timescales of magmatic storage and evolution processes. These parameters provide the source conditions for the dynamics of surface volcanism and the presence of a geothermal system, which modify the thermal and mechanical structure of the crust.

  10. Report of the Workshop on Unmixing the SNCs: Chemical, Isotopic, and Petrologic Components of Martian Meteorites

    NASA Technical Reports Server (NTRS)

    Treiman, Allan H. (Editor); Herd, Christopher D. K. (Editor)

    2002-01-01

    Geochemical and petrologic studies of the Martian meteorites (nicknamed the SNCs) have proliferated in the past few years, from a wealth of new samples and the perfection of new analytical methods. An intriguing result from these studies is that the chemical and isotopic compositions of the Martian meteorites, all basalts or derived from basaltic magma, can be modeled as mixtures of a limited number of components. These mixing components were the focus of the workshop.

  11. Designing a Virtual Manikin Animation Framework Aimed at Virtual Prototyping.

    E-print Network

    Paris-Sud XI, Université de

    Designing a Virtual Manikin Animation Framework Aimed at Virtual Prototyping. Antoine Rennuit1, 2, and analyse human behaviour in the product's environment (for maintenance, ergonomics...), thanks to Virtual of virtual manikins. In order to do so, we are going to express the industrial expectations as for Virtual

  12. Microscopic Theory of Supercapacitors

    NASA Astrophysics Data System (ADS)

    Skinner, Brian Joseph

    As new energy technologies are designed and implemented, there is a rising demand for improved energy storage devices. At present the most promising class of these devices is the electric double-layer capacitor (EDLC), also known as the supercapacitor. A number of recently created supercapacitors have been shown to produce remarkably large capacitance, but the microscopic mechanisms that underlie their operation remain largely mysterious. In this thesis we present an analytical, microscopic-level theory of supercapacitors, and we explain how such large capacitance can result. Specifically, we focus on four types of devices that have been shown to produce large capacitance. The first is a capacitor composed of a clean, low-temperature two-dimensional electron gas adjacent to a metal gate electrode. Recent experiments have shown that such a device can produce capacitance as much as 40% larger than that of a conventional plane capacitor. We show that this enhanced capacitance can be understood as the result of positional correlations between electrons and screening by the gate electrode in the form of image charges. Thus, the enhancement of the capacitance can be understood primarily as a classical, electrostatic phenomenon. Accounting for the quantum mechanical properties of the electron gas provides corrections to the classical theory, and these are discussed. We also present a detailed numerical calculation of the capacitance of the system based on a calculation of the system's ground state energy using the variational principle. The variational technique that we develop is broadly applicable, and we use it here to make an accurate comparison to experiment and to discuss quantitatively the behavior of the electrons' correlation function. The second device discussed in this thesis is a simple EDLC composed of an ionic liquid between two metal electrodes. We adopt a simple description of the ionic liquid and show that for realistic parameter values the capacitance can be as much as three times larger than that of a plane capacitor with thickness equal to the ion diameter. As in the previous system, this large capacitance is the result of image charge formation in the metal electrode and positional correlations between discrete ions that comprise the electric double-layer. We show that the maximum capacitance scales with the temperature to the power -1/3, and that at moderately large voltage the capacitance also decays as the inverse one third power of voltage. These results are confirmed by a Monte Carlo simulation. The third type of device we consider is that of a porous supercapacitor, where the electrode is made from a conducting material with a dense arrangement of narrow, planar pores into which ionic liquid can enter when a voltage is applied. In this case we show that when the electrode is metallic the narrow pores aggressively screen the interaction between neighboring ions in a pore, leading to an interaction energy between ions that decays exponentially. This exponential interaction between ions allows the capacitance to be nearly an order of magnitude larger than what is predicted by mean-field theories. This result is confirmed by a Monte Carlo simulation. We also present a theory for the capacitance when the electrode is not a perfect metal, but has a finite electronic screening radius. When this screening radius is larger than the distance between pores, ions begin to interact across multiple pores and the capacitance is determined by the Yukawa-like interaction of a three-dimensional, correlated arrangement of ions. Finally, we consider the case of supercapacitor electrodes made from a stack of graphene sheets with randomly-inserted "spacer" molecules. For such devices, experiments have produced very large capacitance despite the small density of states of the electrode material, which would seem to imply poor screening of the ionic charge. We show that these large capacitance values can be understood as the result of collective entrance of ions into the graphene stack (GS) and the renormalization

  13. Agreements in Virtual Organizations

    NASA Astrophysics Data System (ADS)

    Pankowska, Malgorzata

    This chapter is an attempt to explain the important impact that contract theory delivers with respect to the concept of virtual organization. The author believes that not enough research has been conducted in order to transfer theoretical foundations for networking to the phenomena of virtual organizations and open autonomic computing environment to ensure the controllability and management of them. The main research problem of this chapter is to explain the significance of agreements for virtual organizations governance. The first part of this chapter comprises explanations of differences among virtual machines and virtual organizations for further descriptions of the significance of the first ones to the development of the second. Next, the virtual organization development tendencies are presented and problems of IT governance in highly distributed organizational environment are discussed. The last part of this chapter covers analysis of contracts and agreements management for governance in open computing environments.

  14. SJU Virtual Education List

    NSDL National Science Digital Library

    New list: VIRTED - Uses of VIRTUAL REALITY in Education is an open, unmoderated discussion list for teachers, students and anyone else interested in the uses of virtual reality in education and learning. The goal of the list is to explore the use and potential uses of virtual reality environments in both traditional and alternative educational settings, the effects of virtual reality environments upon the learning process, and the efficacy of using virtual reality as an educational delivery system. Review of research, publications and observations related to EDUCATIONAL uses of virtual reality are welcome and encouraged. The mission is to shed light on this new avenue of education and learning which takes place in both text based environments as well as graphic environments.

  15. Microscopic study of the string breaking in QCD

    SciTech Connect

    Badalian, A. M., E-mail: badalian@itep.ru; Orlovsky, V. D., E-mail: orlovskii@itep.ru; Simonov, Yu. A., E-mail: simonov@itep.ru [Institute for Theoretical and Experimental Physics (Russian Federation)

    2013-08-15

    Theory of strong decays defines in addition to decay widths also the channel coupling and the mass shifts of the levels above the decay thresholds. In the standard decay models of the {sup 3}P{sub 0} type the decay vertex is taken to be a phenomenological constant {gamma} and such a choice leads to large mass shifts of all meson levels due to real and virtual decays, the latter giving a divergent contribution. Here we show that taking the microscopic details of decay vertex into account, one obtains new string width effect coefficient, which strongly suppresses virtual decay contribution. In addition for a realistic space structure of the decay vertex of highly excited states, the decay matrix elements appear to be strongly different from those, where the constant {gamma} is used. From our analysis also follows that so-called flattening potential can imitate the effects of intermediate decay channels.

  16. COMPUTER ANIMATION AND VIRTUAL WORLDS Comp. Anim. Virtual Worlds (2012)

    E-print Network

    Xu, Kai "Kevin"

    2012-01-01

    COMPUTER ANIMATION AND VIRTUAL WORLDS Comp. Anim. Virtual Worlds (2012) Published online in Wiley John Wiley & Sons, Ltd. KEYWORDS virtual surgery; arthroscopy; ACL reconstruction; procedure simulation animals, cadavers, or plastic models are insufficient for intensive training purpose. The anatomy

  17. Virtual Reality Laboratory

    NSDL National Science Digital Library

    Fogler, H. Scott

    The University of Michigan Virtual Reality Laboratory (VRL) at the College of Engineering explores innovative applications of immersive and non-immersive virtual environments in a variety of areas. For industrial applications, research is focused on virtual prototyping of engineering designs - especially in the automotive and marine industry - the simulation of manufacturing processes, and related engineering tasks. Additional activities include the use of virtual reality in accident simulations, medicine, architecture, archeology, education, and other areas. As an interdisciplinary facility, the VRL collaborates with many disciplines within the university and serves the outside community. Through a combined directorship, the Laboratory cooperates closely with the University of Michigan 3D Lab.

  18. Flirting with virtual reality.

    PubMed

    Friedman, Lawrence

    2005-07-01

    Psychoanalysis encourages patients to experience a virtual reality of the psychoanalytic relationship, in which both image and wish can be experimented with. Originally, the patient's awareness was supposed to move back and forth between the virtual and the actual, in a flickering and uncertain fashion. That is uncomfortable, and analysts have often preferred the domain of virtuality or of actuality, or have denied the distinction altogether. Recent philosophical developments and doubts about transference neurosis and reconstruction further tempt analysts to relax the flickering uncertainty of virtual and actual. Patient and analyst may gain comfort but lose something in the process. PMID:16104333

  19. Probing microscopic mechanical properties of hard tissues with Brillouin spectroscopy

    NASA Astrophysics Data System (ADS)

    Meng, Zhaokai; Yakovlev, Vladislav V.

    2015-02-01

    Mechanical properties of hard tissues play an important role in understanding underlying biological structures, as well as assessing the quality of artificial bone replacement materials. In this study, we employed Brillouin spectroscopy as a non-invasive approach to probe the microscopic elasticity of hard tissues, such as bones. Brillouin spectra were collected using a background free virtually imaged phased array spectrometer. As a reference, Raman spectra were also acquired for each imaging point. Experimental results reveal a positive correlation between the local concentration of the mineral content and the corresponding tissue stiffness, assessed through a Brillouin shift.

  20. Multispectral Imaging Microscope with Millisecond Time Resolution

    E-print Network

    Reid, Scott A.

    Articles Multispectral Imaging Microscope with Millisecond Time Resolution Oleg Khait, Sergey, Wisconsin 53201 A new multispectral imaging microscope with micrometer spatial resolution and millisecond temporal resolution has been developed. The imaging microscope is based on the use of an acousto

  1. Petrology of some lithic fragments from Luna 20.

    NASA Technical Reports Server (NTRS)

    Roedder, E.; Weiblen, P. W.

    1973-01-01

    Microscopic and electron microprobe studies were made of polished thin sections of part of a 30-mg sample of 250- to 500-micron lunar soil returned by Luna 20 from a point between Mare Fecunditatis and Mare Crisium. Very fine-grained lithic (crystalline) rock fragments, composing about one-fifth of the total sample, have mineralogical compositions equivalent to various types of gabbro, anorthositic gabbro, gabbroic anorthosite, and troctolite, with minor basalt. The textures now observed in these fragments are in large part metamorphic. Twenty-seven electron microprobe analyses of minerals from these fragments are presented, including olivine, plagioclase, pyroxene, spinel, nickel-iron, and a Zr-Ti-REE mineral possibly similar to 'phase B' of Lovering and Wark (1971). Analyses of seven melt inclusions and 28 defocused beam analyses of lithic fragments are also given. Some of the fragments contain 'gas' inclusions which, along with the fine grain size, are believed to indicate final crystallization under low pressure near surface conditions.

  2. Vise holds specimens for microscope

    NASA Technical Reports Server (NTRS)

    Greule, W. N.

    1980-01-01

    Convenient, miniature, spring-loaded clamp holds specimens for scanning electron microscope. Clamp is made out of nesting sections of studded angle-aluminum. Specimens are easier to mount and dismount with vise than with conductive adhesive or paint.

  3. Adirondack Under the Microscope-2

    NASA Technical Reports Server (NTRS)

    2004-01-01

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

  4. Scanning Probe Microscope Animation Gallery

    NSDL National Science Digital Library

    This site, hosted by Nanoscience Instruments, has several animations from a scanning probe microscope (SPM). The topics include such items as atomic resolution, buckyballs and electrochemistry. These are good resources that could be used to explore nanoscience through visual means.

  5. Ultrasound Microscope: Quantative Backscatter Imaging

    E-print Network

    Greenaway, Alan

    Ultrasound Microscope: Quantative Backscatter Imaging Srikanta Sharma Academic supervisor: Sandy Cochran Industrial supervisor: Jim McAneny #12;Hypothesis of Intra-membrane Cavitation: Ultrasound Induced and cellular membranes that could explain cavitational and non- cavitational ultrasound induced bio

  6. Theory of a microscopic maser

    Microsoft Academic Search

    P. Filipowicz; J. Javanainen; P. Meystre

    1986-01-01

    A theory is presented for a truly microscopic maser consisting of a single-mode high-Q resonator in which a monoenergetic beam of excited two-level atoms is injected at such a low flux that at most one atom at a time is present inside the cavity. Both a microscopic theory and a heuristic Fokker-Planck approach are presented. It is shown that the

  7. Petrology and reservoir paragenesis in the Sussex 'B' sandstone of the upper Cretaceous Cody Shale, House Creek and Porcupine Fields, Powder River Basin, Wyoming

    SciTech Connect

    Higley, D.K.

    1991-05-03

    Using petrologic and sedimentologic studies, the paper characterizes the influence of sedimentologic and petrologic variations on reservoir heterogeneity in the Sussex 'B' sandstone in the House Creek and Porcupine fields, Powder River Basin, Wyoming. Effects of authigenic minerals on reservoir properties are described in detail for selected inter-ridge and ridge facies sandstones.

  8. Virtual Schools. Literature Review

    ERIC Educational Resources Information Center

    Blazer, Christie

    2009-01-01

    The majority of school districts in the U.S. are providing some form of online learning for their students. In the past, virtual schools primarily targeted advanced students who didn't have access to certain courses in their regular schools. Recently, however, many virtual schools have shifted their focus to credit recovery as a way to provide…

  9. Virtual Learning Environments.

    ERIC Educational Resources Information Center

    Follows, Scott B.

    1999-01-01

    Illustrates the possibilities and educational benefits of virtual learning environments (VLEs), based on experiences with "Thirst for Knowledge," a VLE that simulates the workplace of a major company. While working in this virtual office world, students walk through the building, attend meetings, read reports, receive e-mail, answer the telephone,…

  10. Virtual Classes, Real Policy

    ERIC Educational Resources Information Center

    Beem, Kate

    2010-01-01

    As Internet technology encroached on the public school classroom about a decade ago, Kim Ross, superintendent of the Houston (MN) School District saw an opportunity. The entrepreneurial spirit overtook Ross and his team, and out of that was born the Minnesota Virtual Academy and the Minnesota Center of Online Learning, or MCoOL--two virtual

  11. A Virtual Good Idea

    ERIC Educational Resources Information Center

    Bolch, Matt

    2009-01-01

    School districts across the country have always had to do more with less. Funding goes only so far, leaving administrators and IT staff to find innovative ways to save money while maintaining a high level of academic quality. Creating virtual servers accomplishes both tasks, district technology personnel say. Virtual environments not only allow…

  12. LAYERED AUGMENTED VIRTUALITY

    Microsoft Academic Search

    G. Ahuja; G. Kogut; E. B. Pacis; B. Sights; D. Fellars; H. R. Everett

    Advancements to robotic platform functionalities and autonomy make it necessary to enhance the current capabilities of the operator control unit (OCU) for the operator to better understand the information provided from the robot. Augmented virtuality is one technique that can be used to improve the user interface, augmenting a virtual-world representation with information from on- board sensors and human input.

  13. Virtual Scanning Electron Microscopy

    NSDL National Science Digital Library

    Michael W. Davidson

    This site from Florida State University features an interactive Java tutorial that explores various aspects of virtual scanning electron microscopy. Users can see how specimens appear when magnified in the virtual SEM. The site also features an image gallery and extensive information about different types of microscopy.

  14. Virtual german cockroach

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a German Cockroach (Family Blattidae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  15. Virtual yellowjacket wasp

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a yellowjacket wasp (Family Vespidae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  16. Virtual water strider

    NSDL National Science Digital Library

    0000-00-00

    3D virtual image of a water strider (Family Gerridae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  17. Teaching the Virtual Presentation

    ERIC Educational Resources Information Center

    Flatley, Marie E.

    2007-01-01

    Today, the virtual presentation is catching on rapidly in small, medium, and large businesses alike. A virtual presentation is one delivered live from a desktop or laptop computer to an audience anywhere in the world where there is Internet access. These new Web-based technologies are easy to use and inexpensive, making them readily accessible for…

  18. Rethinking the Virtual

    ERIC Educational Resources Information Center

    Burbules, Nicholas C.

    2004-01-01

    The author builds theoretically off an alternative conception of the virtual, through a series of steps. First, he explores four processes of engagement through which immersion happens (interest, involvement, imagination and interaction); these will prove especially important for understanding the educational potential of virtuality. Second, he…

  19. Who Benefits from Virtuality?

    ERIC Educational Resources Information Center

    Harper, Barry; Hedberg, John G.; Wright, Rob

    2000-01-01

    Discusses the use of constructivist frameworks to develop effective and successful learning environments, including educational software. Topics include technology supporting reform; virtuality and multimedia; attributes of interactive multimedia and virtual reality; and examples of context and learner active participation. (Contains 35…

  20. Digging the Virtual Past

    ERIC Educational Resources Information Center

    Polymeropoulou, Panagiota

    2014-01-01

    In this paper we will investigate the way that the technological progress and the Informatics contributed greatly to the field of Archaeology. There will be analyzed the terms of virtual archaeology and virtual reality in archaeology and there will be an extended reference to the applications and the computer graphics that archaeologists could use…

  1. Virtual orthopedic surgery training

    Microsoft Academic Search

    A. Sourin; O. Sourina; Howe Tet Sen

    2000-01-01

    Medicine is one of the most promising areas for emerging computer graphics and virtual reality techniques. VR training simulators let surgeons practice on virtual body tissue and get the same feedback they would experience in performing a real operation. Hybrid VR systems permit medical practitioners to view the patient overlaid with 3D data sets derived from 3D scanners, thus providing

  2. Virtual Worlds for Educators

    ERIC Educational Resources Information Center

    Dembo, Steve

    2008-01-01

    This article describes an online experience that has not only created a fantasy world for the general public but has enabled some tech-savvy educators to create virtual educational opportunities. Second Life, or SL, is a 3-D Internet-based virtual world created by Linden Lab and populated by nearly 1,000,000 active users worldwide since 2003.…

  3. Scanning Miniature Microscopes without Lenses

    NASA Technical Reports Server (NTRS)

    Wang, Yu

    2009-01-01

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

  4. Datacenter Virtualization 2008 -2009 Enabling a Dynamic Datacenter with Microsoft Virtualization

    E-print Network

    Narasayya, Vivek

    Datacenter Virtualization 2008 - 2009 Enabling a Dynamic Datacenter with Microsoft Virtualization Datacenter Virtualization #12;Enabling a Dynamic Datacenter with Microsoft Virtualization Datacenter Virtualization 2008 - 2009 1 For the latest information, please see http://www.microsoft.com/virtualization

  5. PORTING LEGACY APPLICATIONS TO IMMERSIVE VIRTUAL ENVIRONMENTS

    E-print Network

    Gruchalla, Kenny

    , virtual reality, software engineering, biology. Abstract: Immersive virtual environments are becomingPORTING LEGACY APPLICATIONS TO IMMERSIVE VIRTUAL ENVIRONMENTS A Case Study Kenny GruchallaMOL, into an immersive virtual environment. Presenting macromolecules inside an interactive immersive virtual environment

  6. Accretion, metamorphism, and brecciation of ordinary chondrites - Evidence from petrologic studies of meteorites from Roosevelt County, New Mexico

    NASA Technical Reports Server (NTRS)

    Scott, Edward R. D.; Taylor, G. Jeffrey; Keil, Klaus

    1986-01-01

    The olivines and pyroxenes from twenty-nine ordinary chondrites from Roosevelt County, New Mexico are examined. The mineralogical properties of the chondrites studied are described. Correlations between mineral compositions and petrologic type and between petrologic type and bulk chemistry are analyzed. It is observed that mean CaO concentrations in olivine show significant variations among equilibrated chondrites, but these are not correlated with petrologic type; the degree of heterogeneity of FeO concentrations in olivines of types 4-6 is not correlated with the degree of metamorphism; and mean FeO concentrations of silicates show average increases of 3-5 percent from type 4 to type 6 in each group.

  7. Virtual assembly using virtual reality techniques

    Microsoft Academic Search

    Sankar Jayaram; Hugh I. Connacher; Kevin W. Lyons

    1997-01-01

    Virtual reality is a technology which is often regarded as a natural extension to 3D computer graphics with advanced input and output devices. This technology has only recently matured enough to warrant serious engineering applications. The integration of this new technology with software systems for engineering, design, and manufacturing will provide a new boost to the field of computer-aided engineering.

  8. Virtual Awareness Card for adaptability in Collaborative Virtual Environments

    E-print Network

    Paris-Sud XI, Université de

    - 1 - Virtual Awareness Card for adaptability in Collaborative Virtual Environments Jean-christophe.lapayre@lifc.univ-fcomte.fr Abstract: This article exposes the concept of Virtual Awareness Card in Collaborative Virtual Environments and software properties. Our approach is focused on the Awareness in order to use the awareness information

  9. Licensing Windows for Virtual Desktops Licensing Windows for Virtual Desktops

    E-print Network

    Narasayya, Vivek

    Licensing Windows for Virtual Desktops Licensing Windows for Virtual Desktops This document is intended to explain licensing Windows virtual desktops and how to calculate the number of licenses required for common usage scenarios. #12;Licensing Windows for Virtual Desktops Contents Overview

  10. Virtual stag beetle

    NSDL National Science Digital Library

    0000-00-00

    3D image of a stage beetle (Family Lucanidae). This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the Â?HelpÂ? page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the original models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

  11. Possible petrological controls on the location and time scale of slow slip in SW Japan

    NASA Astrophysics Data System (ADS)

    Wallis, S.; Mizukami, T.; Yokoyama, H.; Hiramatsu, Y.; Arai, S.; Kawahara, H.; Nagaya, T.

    2014-12-01

    To examine the possibility that there was a petrological control on the location and nature of episodic tremor and slip (ETS), we compared the petrological characteristics of wedge mantle material to the results of recent geophysical observations in the Shikoku area, southwest Japan. This study revealed a close relationship between predicted mineral assemblages in the mantle wedge and the characteristics of slow slip behaviour recorded in the Shikoku area: Short-term ETSs take place in the antigorite +olivine stability field and silent long-term slow slip events (SSEs) take place in the antigorite+brucite stability field. The petrology of the mantle wedge may be an important control on the fluid pressure along the subduction interface and influence the time scales of SSEs. The Cretaceous Sanbagawa oceanic subduction complex of SW Japan preserves fragments of the former mantle wedge in contact with subducted slab units. P-T paths and peak P-T conditions show this belt formed as the result of subduction of a young slab under relatively warm conditions. These characteristics make the Sanbagawa belt a good analogue to modern warm subduction zones such as the Philippine Sea subduction zone beneath SW Japan and offer the possibility of directly examining the former plate boundary. Mantle wedge units derived from shallow depths show evidence for widely developed primary brucite and antigorite. In contrast, units derived from greater depths and higher peak temeratures consist dominantly of antigorite and olivine. Observations of the natural serpentinites suggest that the shallow serpentinite with brucite shows higher absorbency of water and provides fluid pathways that can reduce the fluid pore pressure on the subduction boundary.

  12. Stratigraphy, petrology, and structure of the Pingston terrane, Mount Hayes C-5 and C-6 quadrangles, eastern Alaska Range, Alaska

    NASA Astrophysics Data System (ADS)

    Nokleberg, W. J.; Schwab, C. E.; Miyaoka, R. T.; Buhrmaster, C. L.

    Recent field, petrologic, and structural studies of the Pingston terrane in the Mount Hayes C-5 and C-6 quandrangles reveal that in this area the terrane: (1) has a highly distinctive stratigraphy, age, petrology (relict textures, relict minerals, and metamorphic facies), and structure; and (2) differs markedly from that described in previous studies. These more recent studies indicate that the major rock types, in order of decreasing abundance, are meta-andesite, metadacite and metarhyodacite flows and (or) tuff, metabasalt, metagabbro, metavolcanic graywacke, metagray-wacke, metasiltstone, metaquartzite or metachert, and very sparse marble. The general petrography of the major rock units in the Pingston terrane is given.

  13. Care and Feeding of the Compound Microscope

    NSDL National Science Digital Library

    Keirle, Matt

    This lab activity from the Biotechnology Alliance for Suncoast Biology Educators is intended to demonstrate appropriate use of a microscope. It covers the basic care and operation of a compound light microscope. The lesson includes information on how a compound microscope works, a diagram of its parts, tips for usage, a practice activity, and a checklist for putting the microscope away.

  14. Global petrologic variations of the Moon: A ternary-diagram approach

    NASA Technical Reports Server (NTRS)

    Davis, Philip A.; Spudis, Paul D.

    1987-01-01

    A ternary-diagram approach is used to show on a single map as much detailed geochemical information concerning petrologic variations within the lunar crust as is possible. The classification map shows the global spatial distributions of end-member compositions, the transitional spatial relations between end-member compositions, and quantitative estimates of relative proportions of each end member at each pixel location within the orbital groundtracks. The use of elemental ratios in this analysis, instead of the commonly used elemental bivariate diagrams, shows geologic information that is otherwise hidden in individual elemental databases.

  15. Science Nation: Virtual Self

    NSDL National Science Digital Library

    An avatar is a movable image that people design to represent themselves in virtual reality environments or in cyberspace. Avatars are usually for fun and games but could avatars actually change us? Jeremy Bailenson thinks so. With support from the National Science Foundation (NSF), he created the Virtual Human Interaction Lab (VHIL) at Stanford University to study, among other things, the power avatars exert on their real world masters. Sometimes, avatars are designed to be ideal versions of their creators, and there's now evidence that the virtual reality persona begins to influence the real life persona.

  16. Sample holder support for microscopes

    NASA Technical Reports Server (NTRS)

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

    1991-01-01

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

  17. An Entanglement-Enhanced Microscope

    E-print Network

    Takafumi Ono; Ryo Okamoto; Shigeki Takeuchi

    2014-01-31

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

  18. Mosaic of Commemorative Microscope Substrate

    NASA Technical Reports Server (NTRS)

    2008-01-01

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

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

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

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

  19. Communicating Virtual Agents Nicole Krmer

    E-print Network

    Moeller, Ralf

    interfaces ¢ Processing of combined verbal and nonverbal user input · Communicating virtual agents Kopp1 KI3 Communicating Virtual Agents Nicole Krämer nicole.kraemer@uni-koeln.de University of Cologne Kopp & Krämer KI3: Communicating virtual agents Meet a communicating virtual agent... Kopp & Krämer KI3

  20. Virtual-channel flow control

    Microsoft Academic Search

    William J. Dally

    1990-01-01

    Network throughput can be increased by dividing the buffer storage associated with each network channel into several virtual channels [DalSei]. Each physical channel is associated with several small queues, virtual channels, rather than a single deep queue. The virtual channels associated with one physical channel are allocated independently but compete with each other for physical bandwidth. Virtual channels decouple buffer

  1. VWRAP for Virtual Worlds Interoperability

    Microsoft Academic Search

    Joshua Bell; Morgaine Dinova; David Levine

    2010-01-01

    The IETF has chartered a Virtual World Region Agent Protocol Working Group (VWRAP WG). This article briefly describes the history of virtual worlds, the architecture, protocols, and operation of Second Life (a currently prominent virtual world), and the emergence of standards efforts within the virtual world space. The authors detail the current efforts and timeline of the VWRAP WG.

  2. Long working distance interference microscope

    DOEpatents

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

    2004-04-13

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

  3. Jefferson Lab Virtual Tour

    SciTech Connect

    None

    2013-07-13

    Take a virtual tour of the campus of Thomas Jefferson National Accelerator Facility. You can see inside our two accelerators, three experimental areas, accelerator component fabrication and testing areas, high-performance computing areas and laser labs.

  4. Virtual Environments for Health

    NSDL National Science Digital Library

    n/a n/a (Scientific American; )

    2011-08-11

    Can we recreate the health benefits of natural environments by visiting virtual ones? Nature reporter Daniel Cressey visits scientists at the University of Birminghamâ?? who are trying to bring the great outdoors to those who can't get there.

  5. Base Blocks Virtual Manipulative

    NSDL National Science Digital Library

    National Library of Virtual Manipulatives

    2008-12-10

    This virtual manipulative provides base blocks that consist of individual "units," "longs," "flats," and "blocks" (ten of each set for base 10). They can be used to show place value for numbers and to increase understanding of addition and subtraction.

  6. The Virtual Science Classroom

    NSDL National Science Digital Library

    Rick Ferdig

    2008-01-01

    Virtual schooling offers students the opportunity to enroll in a science course not taught at their home school or school district, interact with expert instructors in a particular field, and gain access to subject matter they may have otherwise missed (i.e., teenage moms, home-schooled students, expelled students, etc.). This chapter examines best teaching practices emerging within this new field and showcases specific examples of how various technologies are used within virtual science classrooms.

  7. Virtual Reality Lab Assistant

    NASA Technical Reports Server (NTRS)

    Saha, Hrishikesh; Palmer, Timothy A.

    1996-01-01

    Virtual Reality Lab Assistant (VRLA) demonstration model is aligned for engineering and material science experiments to be performed by undergraduate and graduate students in the course as a pre-lab simulation experience. This will help students to get a preview of how to use the lab equipment and run experiments without using the lab hardware/software equipment. The quality of the time available for laboratory experiments can be significantly improved through the use of virtual reality technology.

  8. Virtual Courseware: Earthquake

    NSDL National Science Digital Library

    This interactive exercise lets students investigate how seismic waves are used to locate the epicenter of an earthquake and determine its magnitude. They will place virtual seismic stations on an interactive map, trigger a virtual explosion, and measure the difference in arrival times of S- and P-waves generated by the explosion. Using this data, they can determine the distance to each station and use triangulation to determine the epicenter of the earthquake.

  9. The virtual wind tunnel

    Microsoft Academic Search

    S. Bryson; C. Levit

    1992-01-01

    The design and implementation of a virtual environment linked to a graphics workstation for the visualization of complex fluid flows are described. The system user wears a stereo head-tracked display, which effectively displays 3-D information, and an instrumented glove to intuitively position flow-visualization tools. The visualization structures and their interfaces in the virtual environment and the implementation hardware and software

  10. Virtual Heritage Network

    NSDL National Science Digital Library

    "The Virtual Heritage Network [VHN], is a new international organisation designed to promote the utilisation of technology for the education, interpretation, conservation and preservation of Natural, Cultural and World Heritage." The heart of VHN is a searchable library that consists of papers, articles, and reports "discussing applications, tools, games, [and] financial and legal aspects" of virtual heritage. Submissions are self-selected and given online reviews by site users, but everything we saw here was professional and, in most cases, had been published elsewhere in academic or news media forums. The site also lets users keep up to date with current developments in the virtual heritage industry via a newsletter, and for members (registration free), offers an email digest of recent submissions to the site, an electronic mailing list, and a forthcoming message board. For the uninitiated, the site has reprinted an article from the November edition of UNESCO's World Heritage Magazine explaining the concept of Virtual Heritage (available from the What is Virtual Heritage? link on the front page). The VHN was established this month by the International Society on Virtual Systems and MultiMedia (VSMM Society) with the support of the UNESCO World Heritage Centre.

  11. VIRTUAL FRAME BUFFER INTERFACE

    NASA Technical Reports Server (NTRS)

    Wolfe, T. L.

    1994-01-01

    Large image processing systems use multiple frame buffers with differing architectures and vendor supplied user interfaces. This variety of architectures and interfaces creates software development, maintenance, and portability problems for application programs. The Virtual Frame Buffer Interface program makes all frame buffers appear as a generic frame buffer with a specified set of characteristics, allowing programmers to write code which will run unmodified on all supported hardware. The Virtual Frame Buffer Interface converts generic commands to actual device commands. The virtual frame buffer consists of a definition of capabilities and FORTRAN subroutines that are called by application programs. The virtual frame buffer routines may be treated as subroutines, logical functions, or integer functions by the application program. Routines are included that allocate and manage hardware resources such as frame buffers, monitors, video switches, trackballs, tablets and joysticks; access image memory planes; and perform alphanumeric font or text generation. The subroutines for the various "real" frame buffers are in separate VAX/VMS shared libraries allowing modification, correction or enhancement of the virtual interface without affecting application programs. The Virtual Frame Buffer Interface program was developed in FORTRAN 77 for a DEC VAX 11/780 or a DEC VAX 11/750 under VMS 4.X. It supports ADAGE IK3000, DEANZA IP8500, Low Resolution RAMTEK 9460, and High Resolution RAMTEK 9460 Frame Buffers. It has a central memory requirement of approximately 150K. This program was developed in 1985.

  12. Optimized graph-based mosaicking for virtual microscopy

    NASA Astrophysics Data System (ADS)

    Steckhan, Dirk G.; Wittenberg, Thomas

    2009-02-01

    Virtual microscopy has the potential to partially replace traditional microscopy. For virtualization, the slide is scanned once by a fully automatized robotic microscope and saved digitally. Typically, such a scan results in several hundreds to thousands of fields of view. Since robotic stages have positioning errors, these fields of view have to be registered locally and globally in an additional step. In this work we propose a new global mosaicking method for the creation of virtual slides based on sub-pixel exact phase correlation for local alignment in combination with Prim's minimum spanning tree algorithm for global alignment. Our algorithm allows for a robust reproduction of the original slide even in the presence of views with little to no information content. This makes it especially suitable for the mosaicking of cervical smears. These smears often exhibit large empty areas, which do not contain enough information for common stitching approaches.

  13. Microscopic Social Influence Mudhakar Srivatsa

    E-print Network

    Liu, Ling

    influence his/her friends in a dynamic, network-wise manner (i.e., dependent on both social and object networked systems [1, 2, 3]. It is well recognized that social influence is one complex and subtle forceMicroscopic Social Influence Ting Wang Mudhakar Srivatsa Dakshi Agrawal Ling Liu IBM Research

  14. Profiling with the electron microscope.

    NASA Technical Reports Server (NTRS)

    Vedder, J. F.; Lem, H. Y.

    1972-01-01

    Discussion of a profiling technique using a scanning electron microscope for obtaining depth information on a single micrograph of a small specimen. A stationary electron beam is used to form a series of contamination spots in a line across the specimen. Micrographs obtained by this technique are useful as a means of projection and display where stereo viewers are not practical.

  15. The microscope in the hatchery

    USGS Publications Warehouse

    Fish, F.F.

    1935-01-01

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

  16. MEMS optical scanners for microscopes

    Microsoft Academic Search

    Hiroshi Miyajima; Kenzi Murakami; Masahiro Katashiro

    2004-01-01

    Microelectromechanical systems (MEMS) optical scanners have been around for more than two decades. Various applications have been presented, but few of them have advanced to the commercial level to date due to the difficulties of combination of optics and MEMS devices. This paper presents our activities of investigating MEMS scanner applications related to microscopic imaging. First, we started with developing

  17. High-resolution electron microscope

    NASA Technical Reports Server (NTRS)

    Nathan, R.

    1977-01-01

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

  18. Chasing Meteors With a Microscope.

    ERIC Educational Resources Information Center

    Jones, Richard C.

    1993-01-01

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

  19. Light-Fueled Microscopic Walkers.

    PubMed

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

    2015-07-01

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

  20. Ethanol Myths: Under the Microscope

    E-print Network

    Pawlowski, Wojtek

    Ethanol Myths: Under the Microscope . .GrowingAmerica'sEnergyFuture Biomass MYTH: Ethanol cannot supplies. FACT: Corn is only one source of biofuel. In the future, a significant amount of ethanol will be made from other biomass sources. The corn used to produce ethanol today is the type used as animal feed

  1. Nature Study with the Microscope.

    ERIC Educational Resources Information Center

    Sollberger, Dwight E.

    1991-01-01

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

  2. Petrologic Constraints on Imbrication, Metamorphism, and Uplift in the SW Tauern Window, Eastern Alps

    NASA Astrophysics Data System (ADS)

    Selverstone, Jane

    1985-12-01

    The pressure-temperature-time-deformation (PTtd) history of two tectonic units in the southwest Tauern Window (Austria/Italy) is evaluated from P-T paths of metamorphism and uplift, geochronologic data, and observations on fabric development. Petrologic data indicate burial of the Lower Schieferhülle (LSH) to depths of ? 35 km and the adjacent Upper Schieferhülle (USH) to only 24-28 km; the units are now separated by only 2 km of section. Metamorphism was postkinematic in the LSH and synkinematic in the USH. Correlation of P-T path reversals calculated from zoned garnets in the two units, however, indicates that juxtaposition of the LSH and USH occurred prior to metamorphism. Temperature-time and depth-time diagrams for both units show increasing cooling rates and decreasing uplift rates as the rocks approached the surface. Both the petrologic data and the depth-time profiles for the LSH and USH point to a history of differential uplift in the early stages of decompression. Textural features indicate that the LSH behaved as an essentially rigid body during uplift, whereas the USH experienced extensive ductile shearing. The PTtd data for the LSH and USH are incorporated into a model for continental collision in the Eastern Alps. Initial tectonic uplift of the LSH was accompanied by ductile thinning of the USH and overlying Austroalpine units. Final uplift and erosion affected all of the units "en masse".

  3. Interactive computer programs for petrologic modeling with extended Q-mode factor analysis

    USGS Publications Warehouse

    Miesch, A.T.

    1976-01-01

    An extended form of Q-mode factor analysis may be used if the row-sums of the data matrix are constant and can be helpful especially in developing and testing petrologic-mixing models for igneous systems. The first step is to represent the sample compositions as unit vectors in M-dimensional space and then to project them into space of fewer dimensions (m) as determined to be appropriate from a factor-variance diagram. Compositions thought to be those of possible end-members in the petrologic system then are represented as vectors in the M-dimensional space and projected into the same space as the sample vectors. If these vectors remain close to unity in length after projection, the corresponding compositions can serve as end-member compositions for the model. After m suitable end-member compositions have been identified, each sample composition is expressed as a mixture of the end-members by computation of the composition loadings. The interactive computer programs presented are useful in these procedures because of the trial-and-error nature of the modeling procedures. ?? 1976.

  4. Petrology and Geochemistry of Unbrecciated Harzburgitic Diogenite MIL 07001: A Window Into Vestan Geological Evolution

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Peng, Z. X.; Mertzman, S. A.; Mertzman, K. R.

    2014-01-01

    There is a strong case that asteroid 4 Vesta is the parent of the howardite, eucrite and diogenite (HED) meteorites. Models developed for the geological evolution of Vesta can satisfy the compositions of basaltic eucrites that dominate in the upper crust. The bulk compositional characteristics of diogenites - cumulate harzburgites and orthopyroxenites from the lower crust - do not fit into global magma ocean models that can describe the compositions of basaltic and cumulate eucrites. Recent more detailed formation models do make provision for a more complicated origin for diogenites, but this model has yet to be completely vetted. Compositional studies of bulk samples has led to the hypothesis that many diogenites were formed late by interaction of their parent melts with a eucritic crust, but those observations may alternatively be explained by subsolidus equilibration of trace elements between orthopyroxene and plagioclase and Ca-phosphate in the rocks. Differences in radiogenic Mg-26 content between diogenites and eucrites favors early formation of the former, not later formation. Understanding the origin of diogenites is crucial for understanding the petrologic evolution of Vesta. We have been doing coordinated studies of a suite of diogenites including petrologic investigations, bulk rock major and trace element studies, and in situ trace element analyses of orthopyroxene. Here we will focus on an especially unusual, and potentially key, diogenite, MIL 07001.

  5. Cumberland Falls chondritic inclusions - Mineralogy/petrology of a forsterite chondrite suite

    NASA Technical Reports Server (NTRS)

    Neal, C. W.; Lipschutz, M. E.

    1981-01-01

    The mineralogy and petrology of a suite of chondritic inclusions from the Cumberland Falls aubrite are investigated in order to clarify the relation of the inclusions to each other, forsterite chondrites, and the aubrites. Thin sections of nine chondritic inclusions and the achondritic matrix of Cumberland Falls were examined in reflected light, then analyzed for up to 12 elements by electron microprobe techniques. Minerals detected in abundant quantities include low-Ca pyroxene, olivine, plagioclase, kamacite, taenite, schreibersite, troilite, ferroan alabandite and daubreelite; diospide, oldhamite and a Ti-rich sulfide are found in one or two inclusions. The mineralogic compositions indicate similar degrees of reduction for the inclusions in the Cumberland Falls meteorites and in four meteorites identified as forsterite chondrites (Kakangari, Mt. Morris, Pontlyfni and Winona). The inclusions are found to be of a primitive composition, corresponding to petrological types 2 or 3, while the identification of jadeitic pyroxene in nearly all inclusions indicates a substantial degree of shock. The results suggest that the inclusions formed from nebular material that condensed and accreted over a broad redox range, and experienced tertiary shock in a collision with an enstatite meteorite in which the Cumberland Falls meteorite formed.

  6. Petrological and seismic precursors of the paroxysmal phase of the last Vesuvius eruption on March 1944

    NASA Astrophysics Data System (ADS)

    Pappalardo, Lucia; D'Auria, Luca; Cavallo, Andrea; Fiore, Stefano

    2014-09-01

    Abrupt transitions in style and intensity are common during volcanic eruptions, with an immediate impact on the surrounding territory and its population. Defining the factors trigger such sudden shifts in the eruptive behavior as well as developing methods to predict such changes during volcanic crises are crucial goals in volcanology. In our research, the combined investigation of both petrological and seismic indicators has been applied for the first time to a Vesuvius eruption, that of March 1944 that caused the present dormant state of the volcano. Our results contribute to elucidate the evolution of the conduit dynamics that generated a drastic increase in the Volcanic Explosivity Index, associated to the ejection of huge amount of volcanic ash. Remarkably, our study shows that the main paroxysm was announced by robust changes in petrology consistent with seismology, thus suggesting that the development of monitoring methods to assess the nature of ejected juvenile material combined with conventional geophysical techniques can represent a powerful tool for forecasting the evolution of an eruption towards violent behavior. This in turn is a major goal in volcanology because this evidence can help decision-makers to implement an efficient safety strategy during the emergency (scale and pace of evacuation).

  7. Petrological and seismic precursors of the paroxysmal phase of the last Vesuvius eruption on March 1944

    PubMed Central

    Pappalardo, Lucia; D'Auria, Luca; Cavallo, Andrea; Fiore, Stefano

    2014-01-01

    Abrupt transitions in style and intensity are common during volcanic eruptions, with an immediate impact on the surrounding territory and its population. Defining the factors trigger such sudden shifts in the eruptive behavior as well as developing methods to predict such changes during volcanic crises are crucial goals in volcanology. In our research, the combined investigation of both petrological and seismic indicators has been applied for the first time to a Vesuvius eruption, that of March 1944 that caused the present dormant state of the volcano. Our results contribute to elucidate the evolution of the conduit dynamics that generated a drastic increase in the Volcanic Explosivity Index, associated to the ejection of huge amount of volcanic ash. Remarkably, our study shows that the main paroxysm was announced by robust changes in petrology consistent with seismology, thus suggesting that the development of monitoring methods to assess the nature of ejected juvenile material combined with conventional geophysical techniques can represent a powerful tool for forecasting the evolution of an eruption towards violent behavior. This in turn is a major goal in volcanology because this evidence can help decision-makers to implement an efficient safety strategy during the emergency (scale and pace of evacuation). PMID:25199537

  8. Pet Rock Project: A Semester-long Exercise for Igneous and Metamorphic Petrology

    NSDL National Science Digital Library

    Darrell Henry

    The pet rock project is a semester-long project in which each student randomly selects an igneous or metamorphic rock from the instructor or brings in a rock from an appropriate locality, and follows all of the steps a petrologist would take to interpret an igneous or metamorphic rock from an unknown area. This project runs in the background of the petrology class during the initial part of the semester while the student acquires the petrologic skills to make more sophisticated interpretations. The culmination of the project is for each student to spend several hours with the instructor using the electron microprobe to identify more difficult minerals with certainty, to produce high quality digital backscattered electron images and to obtain quantitative electron microprobe analyses of selected minerals that aid in the interpretation of the pet rock. Ultimately, the student interprets the rock, generally with the assistance of the instructor, writes a report explaining the process and results and presents the results to the class.

  9. Towards Calibrating the Vestan Regolith: Correlating the Petrology, Chemistry and Spectroscopy of Howardites

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Ammannito, E.; Hiroi, T.; De Angelis, S.; Di Iorio, T.; Pieters, C. M.; De Sanctis, C.

    2013-01-01

    The Dawn spacecraft carries a visible and infrared mapping spectrometer (VIR) [1] that has acquired spectra for the wavelength range 0.25-5.0 µm at various spatial resolutions covering much of the vestan surface [2]. Through comparison of VIR spectra with laboratory spectra of howardite, eucrite and diogenite meteorites, the distribution of more diogenite-rich and more eucrite-rich terranes on Vesta have been mapped [3], but these maps are qualitative in nature. The available laboratory spectra are not well-integrated with detailed sample petrology or composition limiting their utility for lithologic mapping. Importantly, howardites are now recognized to come in two subtypes, regolithic and fragmental [4]. The former are breccias assembled in part from true regolith, while the latter have had much less exposure to the space environment. We are attempting to develop a more quantitative basis for mapping the distribution of lithologic types on Vesta through acquiring laboratory spectra on splits of howardites that have been petrologically and chemically characterized [5]. Noble gas analyses have been done on some allowing identification of those howardites that have been exposed in the true regolith of Vesta [6].

  10. Petrology, geochemistry, and age of low-Ti mare-basalt meteorite Northeast Africa 003-A: A possible member

    E-print Network

    Petrology, geochemistry, and age of low-Ti mare-basalt meteorite Northeast Africa 003-A: A possible member of the Apollo 15 mare basaltic suite Jakub Haloda a,b,*, Patricie Ty´cova´ a,b , Randy L. Korotev for this study, (NEA 003-A) consists of mare-basalt and a smaller adjacent portion ($25 vol%) is a basaltic

  11. The Influence of Mantle Petrology on Basin Subsidence During Rifting Nina S.C. Simon & Yuri Y. Podladchikov

    E-print Network

    Simon, Nina

    The Influence of Mantle Petrology on Basin Subsidence During Rifting Nina S.C. Simon & Yuri Y-spinel and spinel plagioclase transitions in the lithospheric mantle have the most profound effect on uplift/subsidence- rift subsidence recorded in the basin is directly proportional to the total amount of plagioclase

  12. Detrital thermochronology and sediment petrology of the middle Siwaliks along the Muksar Khola section in eastern Nepal

    E-print Network

    Utrecht, Universiteit

    section in eastern Nepal François Chirouze a , Matthias Bernet a, , Pascale Huyghe a , Véronique Erens b Formation in eastern Nepal along the Muksar Khola section for thermochronologic and sediment petrologic Formation of eastern Nepal has some similarities but also differences with published data for western

  13. Mineralogic, petrologic, and geochemical studies of the volcanic rocks at Yucca Mountain, Nevada, for high-level waste disposal

    Microsoft Academic Search

    D. Vaniman; D. Bish; D. Broxton; F. Byers; B. Carlos; S. Levy; S. Chipera

    1988-01-01

    Studies of mineralogy, petrology, and geochemistry at a candidate high-level waste repository site must address three primary concerns: (a) possible future geologic events that can compromise waste isolation, (b) possible conflicting site uses, and (c) the natural ability of the site to contain radionuclide waste. Data are being collected to address these concerns for a potential unsaturated repository location at

  14. Origin of New Faculty in Sedimentary Petrology at Ph.D.-Granting Universities in the United States and Canada.

    ERIC Educational Resources Information Center

    Thornton, Scott E.

    1981-01-01

    To aid prospective graduate students in sedimentary petrology who wish to teach at colleges or universities, 121 doctoral graduates in this field are traced to their present appointments in higher education. Only 31 percent of these graduates attained this career goal. (Author/WB)

  15. Petrologic insights into basaltic volcanism at historically active Hawaiian volcanoes: Chapter 6 in Characteristics of Hawaiian volcanoes

    USGS Publications Warehouse

    Helz, Rosalind L.; Clague, David A.; Sisson, Thomas W.; Thornber, Carl R.

    2014-01-01

    Contributions to our knowledge of the nature of the mantle source(s) of Hawaiian basalts are reviewed briefly, although this is a topic where debate is ongoing. Finally, our accumulated petrologic observations impose constraints on the nature of the summit reservoirs at K?lauea and Mauna Loa, specifically whether the summit chamber has been continuous or segmented during past decades.

  16. Hydrothermal alteration and tectonic setting of intrusive rocks from East Brawley, Imperial Valley: an application of petrology to geothermal reservoir analysis

    SciTech Connect

    Keskinen, M.; Sternfeld, J.

    1982-01-01

    A geothermal well near East Brawley intersected a series of thin (3 to 35m) diabasic to dioritic intrusives. The petrology and chemistry of these meta-igneous rocks can provide insight into the thermal and fluid chemical characteristics of the reservoir and into the processes of magma generation at depth. A description of the rock types and their hydrothermal alteration is presented in order to increase the petrologic data base relating to this important facet of the geothermal potential of the Salton Trough and to provide a case study illustrating how detailed petrologic examination of well cuttings can provide important input in the construction of a geothermal reservoir model.

  17. VIRTUAL TYRE PRODUCTION: LEARNING INDUSTRIAL PROCESS THROUGH AN INFORMED VIRTUAL ENVIRONMENT

    E-print Network

    Paris-Sud XI, Université de

    VIRTUAL TYRE PRODUCTION: LEARNING INDUSTRIAL PROCESS THROUGH AN INFORMED VIRTUAL ENVIRONMENT J through an Informed Virtual Environ- ment integrating different aspects of human activity and ex- pertise-- Industrial training, informed virtual envi- ronnement, tyre production, virtual reality 1. INTRODUCTION

  18. Hyperbaric Hydrothermal Atomic Force Microscope

    DOEpatents

    Knauss, Kevin G. (Livermore, CA); Boro, Carl O. (Milpitas, CA); Higgins, Steven R. (Laramie, WY); Eggleston, Carrick M. (Laramie, WY)

    2003-07-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  19. Hyperbaric hydrothermal atomic force microscope

    DOEpatents

    Knauss, Kevin G. (Livermore, CA); Boro, Carl O. (Milpitas, CA); Higgins, Steven R. (Laramie, WY); Eggleston, Carrick M. (Laramie, WY)

    2002-01-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  20. Nanocarpets for Trapping Microscopic Particles

    NASA Technical Reports Server (NTRS)

    Noca, Flavio; Chen, Fei; Hunt, Brian; Bronikowski, Michael; Hoenk, Michael; Kowalczyk, Robert; Choi, Daniel

    2004-01-01

    Nanocarpets that is, carpets of carbon nanotubes are undergoing development as means of trapping microscopic particles for scientific analysis. Examples of such particles include inorganic particles, pollen, bacteria, and spores. Nanocarpets can be characterized as scaled-down versions of ordinary macroscopic floor carpets, which trap dust and other particulate matter, albeit not purposefully. Nanocarpets can also be characterized as mimicking both the structure and the particle-trapping behavior of ciliated lung epithelia, the carbon nanotubes being analogous to cilia. Carbon nanotubes can easily be chemically functionalized for selective trapping of specific particles of interest. One could, alternatively, use such other three-dimensionally-structured materials as aerogels and activated carbon for the purposeful trapping of microscopic particles. However, nanocarpets offer important advantages over these alternative materials: (1) Nanocarpets are amenable to nonintrusive probing by optical means; and (2) Nanocarpets offer greater surface-to-volume ratios.

  1. One-Angstrom microscope update

    SciTech Connect

    O'Keefe, Michael A.

    1999-04-04

    The One-Angstrom Microscope project has attained its goal, and is now producing images down to 1 Angstrom resolution. We have demonstrated transmission electron microscopy of defect structures down to a resolution of 1.1 Angstrom, with evidence that 0.89 Angstrom will be possible. This level of resolution will soon be made available to all those NCEM users who have a requirement for sub-Angstrom resolution.

  2. Science 101 : How Do Microscopes Work?

    NSDL National Science Digital Library

    Sarah Zimov

    2004-01-01

    Microscopes allow scientists to examine everyday objects in extraordinary ways. They provide high-resolution images that show objects in fine detail. This articles includes details on how microscopes work and how they enhance the scientific process.

  3. The virtual tricorder: a uniform interface for virtual reality

    Microsoft Academic Search

    Matthias M. Wloka; Eliot Greenfield

    1995-01-01

    We describe a new user-interface metaphor for immersive virtual reality — the virtual tricorder. The virtual tricor der visually duplicates a six-degrees-of-freedom input devic e in the virtual environment. Since we map the input device to the tricorder one-to-one at all times, the user identifies the two. Thus, the resulting interface is visual as well as tacti le, multipurpose, and

  4. Microscope Image of Scavenged Particles

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image from NASA's Phoenix Mars Lander's Optical Microscope shows a strongly magnetic surface which has scavenged particles from within the microscope enclosure before a sample delivery from the lander's Robotic Arm. The particles correspond to the larger grains seen in fine orange material that makes up most of the soil at the Phoenix site. They vary in color, but are of similar size, about one-tenth of a millimeter.

    As the microscope's sample wheel moved during operation, these particles also shifted, clearing a thin layer of the finer orange particles that have also been collected. Together with the previous image, this shows that the larger grains are much more magnetic than the fine orange particles with a much larger volume of the grains being collected by the magnet. The image is 2 milimeters across.

    It is speculated that the orange material particles are a weathering product from the larger grains, with the weathering process both causing a color change and a loss of magnetism.

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

  5. Compact Microscope Imaging System Developed

    NASA Technical Reports Server (NTRS)

    McDowell, Mark

    2001-01-01

    The Compact Microscope Imaging System (CMIS) is a diagnostic tool with intelligent controls for use in space, industrial, medical, and security applications. The CMIS can be used in situ with a minimum amount of user intervention. This system, which was developed at the NASA Glenn Research Center, can scan, find areas of interest, focus, and acquire images automatically. Large numbers of multiple cell experiments require microscopy for in situ observations; this is only feasible with compact microscope systems. CMIS is a miniature machine vision system that combines intelligent image processing with remote control capabilities. The software also has a user-friendly interface that can be used independently of the hardware for post-experiment analysis. CMIS has potential commercial uses in the automated online inspection of precision parts, medical imaging, security industry (examination of currency in automated teller machines and fingerprint identification in secure entry locks), environmental industry (automated examination of soil/water samples), biomedical field (automated blood/cell analysis), and microscopy community. CMIS will improve research in several ways: It will expand the capabilities of MSD experiments utilizing microscope technology. It may be used in lunar and Martian experiments (Rover Robot). Because of its reduced size, it will enable experiments that were not feasible previously. It may be incorporated into existing shuttle orbiter and space station experiments, including glove-box-sized experiments as well as ground-based experiments.

  6. Microscopic NDE of hidden corrosion

    NASA Astrophysics Data System (ADS)

    Blackshire, James L.; Hoffmann, Jochen; Kropas-Hughes, Claudia V.; Tansel, Ibrahim

    2003-07-01

    The detection and microscopic characterization of hidden corrosion has recently been a focus of several advanced NDE research efforts. A variety of approaches have been suggested, with laser ultrasonic (LU), scanning acoustic microscopy (SAM), thermography,and x-ray systems being four of the most promising NDE techniques. In this effort, a side-by-side comparison of each of these four techniques was conducted with the goal of assessing the detailed microscopic features of engineered and realistic hidden pitting corrosion reference samples. The reference samples included laser-etched cutouts and electro-chemically created surface pits ranging in size for 250 ?m to 5 mm in surface extent, and depths of 25 ?m to 1 mm. The effects of material loss/topography, corrosion-byproduct, and paint thickness levels were all addressed. Variations in measurement sensitivity, detectivity, and spatial resolution were studied, with particular attention being focused on the ability of the NDE technique to not only detect the hidden corrosion, but to provide any additional information regarding the microscopic nature of the corrosion area, its roughness, material loss levels, and pitting sharpness. In all cases, the NDE techniques provided an 'image' of the hidden corrosion areas, with some capability for assessing the internal structures of the pits from the measured signal levels or brightness levels of the measured image fields.

  7. Virtual Field Trip

    NSDL National Science Digital Library

    This immersive multimedia application was developed to provide students with the ability to virtually explore areas on Earth that have been identified as analog sites to regions on Mars. Users zoom in from a global view down to a surface view of a site, where they are placed into a 360 degree spherical virtual reality surface panorama. They can navigate around the site selecting various objects and listening to scientists to learn more about how and why the site was chosen, how it relates to Mars, and why it is of interest. The environment consists of various linked 360 degree spherical stitched virtual reality environments, 3D based layered environments, global fly downs, as well as compressed streaming video files for each area of research. The software is downloadable as compressed files for PC or Mac.

  8. Virtual Courseware: Earthquake

    NSDL National Science Digital Library

    Gary Novak

    2000-04-25

    Virtual Earthquake is an interactive web-based program designed to introduce the concepts of how an earthquake epicenter is located and how the Richter magnitude of an earthquake is determined. Virtual Earthquake shows the recordings of an earthquake's seismic waves detected by instruments far away from the earthquake. The instrument recording the seismic waves is called a seismograph and the recording is a seismogram. The point of origin of an earthquake is called its focus and the point on the earth's surface directly above the focus is the epicenter. You are to locate the epicenter of an earthquake by making simple measurements on three seismograms that are generated by the Virtual Earthquake program. Additionally, you will be required to determine the Richter Magnitude of that quake from the same recordings. Richter Magnitude is an estimate of the amount of energy released during an earthquake.

  9. Pulsar virtual observatory

    E-print Network

    M. Keith; B. Harbulot; A. Lyne; J. Brooke

    2007-01-04

    The Pulsar Virtual Observatory will provide a means for scientists in all fields to access and analyze the large data sets stored in pulsar surveys without specific knowledge about the data or the processing mechanisms. This is achieved by moving the data and processing tools to a grid resource where the details of the processing are seen by the users as abstract tasks. By developing intelligent scheduling middle-ware the issues of interconnecting tasks and allocating resources are removed from the user domain. This opens up large sets of radio time-series data to a wider audience, enabling greater cross field astronomy, in line with the virtual observatory concept. Implementation of the Pulsar Virtual Observatory is underway, utilising the UK National Grid Service as the principal grid resource.

  10. Deep Seismic Reflectivity at Volcanic Margins: Reflections from the Petrological Moho or from within the Mantle?

    NASA Astrophysics Data System (ADS)

    Kusznir, Nick; Roberts, Alan; Bellingham, Paul

    2015-04-01

    Advances in deep long-offset seismic-reflection acquisition and processing now frequently provide imaging of strong and laterally continuous reflectors in the TWTT range of 10 to 14 seconds. While an initial interpretation might be that these reflectors correspond to the crust-mantle interface, this interpretation may in some cases be incorrect or over-simplistic. Do these deep reflectors correspond to the petrological Moho or could they be located within the mantle? Examples of deep laterally-coherent reflectivity can be seen within the ocean-continent transition of the Argentine, Uruguayan and S Brazilian volcanic margins of the S Atlantic. An initial qualitative interpretation of the seismic data suggests the presence of deep crustal "keels" or crustal roots underlying well developed seaward dipping reflectors (SDRs). Joint inversion of the PSTM time-domain seismic reflection and gravity anomaly data has been used to determine the average interval density and seismic velocity between base sediment and the deep seismic reflectivity. Joint inversion densities and seismic velocities for this depth interval reach values in excess of 3000 kg/m3 and 7.0 km/sec for the entire thickness of the interval, substantially in excess of densities and velocities observed for normal oceanic and continental crust. The high densities determined from joint seismic-gravity inversion under the SDR regions are also consistent with results from flexural subsidence analysis. We consider two interpretations of these results. One interpretation is that the strong deep reflectivity corresponds to the base of the petrological crust and that the crust has an abnormally high average density and seismic velocity due to high-temperature mantle-plume-related magmatism. An alternative interpretation is that the deep seismic reflectivity is located within the mantle beneath the petrological Moho, and that the high density and seismic velocity result from averaging of both crustal basement (~2850 kg/m3) and mantle (~3300 kg/m3) values. In some examples, additional analysis of the deep seismic reflection data suggests that the latter interpretation is correct i.e. the strong deep seismic reflectivity is located within the mantle. The presence of well developed SDRs above suggests that the strong deep seismic reflectivity within the mantle may be magmatic in origin.

  11. Petrology of Deep Storage, Ingassing, and Outgassing of Terrestrial Carbon (Invited)

    NASA Astrophysics Data System (ADS)

    Dasgupta, R.

    2010-12-01

    Fluxes of carbon between the mantle and the exosphere modulate Earth's atmosphere and climate on short to long time scales. Carbon geochemistry of mantle-derived samples suggests that the fluxes associated with deep cycle are in the order of 1012-13 g C/yr and the reservoir sizes involved in deep carbon are in the order of 1022-23 g C. Petrology of deep storage is critical to this long-term evolution and distribution of terrestrial carbon. Here I synthesize the petrologic constraints that are critical in understanding the evolution of deep terrestrial carbon. Carbon is a volatile, trace element in the Earth's mantle. But unlike most other trace elements including hydrogen, which in the Earth’s mantle is held in dominant silicate minerals, carbon is stored in accessory phases. The accessory phase of interest, with increasing depth, changes typically from fluids/melts ? calcite/dolomite ? magnesite ? diamond/ Fe-rich alloy/ Fe-metal carbide, assuming that the mass balance and oxidation state are buffered solely by silicates. If, however, carbon is sufficiently abundant, locally it may overwhelm the mass balance and redox buffer of the Earth’s interior. For example, carbon may reside as carbonate even in the deep mantle, which otherwise is thought to be reduced and not conducive for carbonate stability. If Earth's deep mantle is Fe-metal saturated, carbon storage in metal alloy and as metal carbide is difficult to avoid for depleted and enriched domains, respectively. Carbon ingassing to the interior is aided by modern subduction of the carbonated oceanic lithosphere, whereas outgassing from the mantle is controlled by decompression melting of carbon-bearing mantle. Carbonated melting at >300 km depth or redox melting of diamond-bearing or metal/metal carbide-bearing mantle at somewhat shallower depth generates carbonatitic and carbonated silicate melts, which are the chief agents for liberating carbon from the solid Earth to the exosphere. Petrology allows net ingassing of carbon into the mantle in the modern Earth, but in the hotter subduction zones that prevailed during the Hadean, Archean, and most of Proterozoic, recycled carbonate likely was released at shallow mantle wedge depths and may have returned to the exosphere more efficiently through arc volcanism. Release of primordial carbon through magmatism was also likely more vigorous owing to deeper intersection of solidi and hotter mantle adiabat. Inefficient ingassing, along with efficient outgassing, may have maintained the ancient mantle carbon-poor. If this is accurate, then the present-day carbon budget of the mantle is likely shaped mostly from NeoProterozoic through Phanerozoic, a time when thermal state of the planet allowed deep subduction of carbonated crustal rocks.

  12. Composition and Petrology of HED Polymict Breccias: The Regolith of (4) Vesta

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Cartwright, J. A.; Herrin, J. S.; Mertzman, S. A.; Mertzman, K. R.; Peng, Z. X.; Quinn, J. E.

    2012-01-01

    The polymict breccias of the howardite, eucrite and diogenite (HED) clan of meteorites preserve records of regolith processes that occur on Vesta, their putative home world. These breccias -- howardites, polymict eucrites and polymict diogenites -- are impact-engendered mixtures of diogenites and eucrites. The compositions of polymict breccias can be used to constrain the lithologic diversity of the vestan crust and the excavation depths of these materials. We have done petrological and compositional studies of multiple samples of 5 polymict eucrites and 28 howardites to investigate these issues. Older analyses were done on samples of approx 0.5 gram mass by INAA; newer analyses on samples of approx 5 gram mass by XRF and ICP-MS. We estimate the percentage of eucritic material (POEM) of polymict breccias by comparing their Al and/or Ca contents to those of average basaltic eucrite and diogenite. Our samples have POEM ranging from 28 to 98; adding two polymict diogenites from extends the range to POEM 10. One hypothesis is that ancient, well-mixed vestan regolith has POEM approx 67 and has a higher content of admixed impactor material. Several of our howardites have POEM of 59-74 (Al and/or Ca contents +/- 10% of POEM 67); about a third have Ni contents >300 micro g/g suggesting they contain >2% chondritic material (CM and/or CR). These may be regolithic howardites. Only one (LEW 85313) contains Ne dominated by a solar wind (SW) component. PCA 02066 is dominated by impact-melt material of polymict parentage and petrologically appears to be a mature regolith breccia, yet it does not contain SW-Ne. GRO 95602 falls within the POEM window, contains SW-Ne], yet has a Ni content of 193 micro g/g. Its petrologic characteristics suggest it was formed from immature regolith (no polymict breccia clasts; no glass). Trace element characteristics of the polymict breccias demonstrate the dominance of main-group eucrites as the basaltic component. Mixing diagrams of Zr, Nb, Ba, Hf and Ta with Al show no evidence for a significant contribution from Stannern-trend eucrites. An exception is polymict eucrite LEW 86001 (POEM 92), which is dominated by Stannern-trend basaltic debris. Howardite LAP 04838 (POEM 84) has higher incompatible trace concentrations than other polymict breccias (excluding LEW 86001), and either contains a Stannern-trend basaltic component, or has a significant contributions from evolved eucrites like Nuevo Laredo.

  13. Intraoperative virtual brain counseling

    NASA Astrophysics Data System (ADS)

    Jiang, Zhaowei; Grosky, William I.; Zamorano, Lucia J.; Muzik, Otto; Diaz, Fernando

    1997-06-01

    Our objective is to offer online real-tim e intelligent guidance to the neurosurgeon. Different from traditional image-guidance technologies that offer intra-operative visualization of medical images or atlas images, virtual brain counseling goes one step further. It can distinguish related brain structures and provide information about them intra-operatively. Virtual brain counseling is the foundation for surgical planing optimization and on-line surgical reference. It can provide a warning system that alerts the neurosurgeon if the chosen trajectory will pass through eloquent brain areas. In order to fulfill this objective, tracking techniques are involved for intra- operativity. Most importantly, a 3D virtual brian environment, different from traditional 3D digitized atlases, is an object-oriented model of the brain that stores information about different brain structures together with their elated information. An object-oriented hierarchical hyper-voxel space (HHVS) is introduced to integrate anatomical and functional structures. Spatial queries based on position of interest, line segment of interest, and volume of interest are introduced in this paper. The virtual brain environment is integrated with existing surgical pre-planning and intra-operative tracking systems to provide information for planning optimization and on-line surgical guidance. The neurosurgeon is alerted automatically if the planned treatment affects any critical structures. Architectures such as HHVS and algorithms, such as spatial querying, normalizing, and warping are presented in the paper. A prototype has shown that the virtual brain is intuitive in its hierarchical 3D appearance. It also showed that HHVS, as the key structure for virtual brain counseling, efficiently integrates multi-scale brain structures based on their spatial relationships.This is a promising development for optimization of treatment plans and online surgical intelligent guidance.

  14. VIRTUAL THEATER for Industrial Training: A Collaborative Virtual Environment

    E-print Network

    Ottawa, University of

    VIRTUAL THEATER for Industrial Training: A Collaborative Virtual Environment J.C.OLIVEIRA1 , S applications. In this paper we present a CVE prototype developed for industrial tele-training. We are showing, Virtual Theater, Multimedia, Video Processing, Industrial Training. 1 Introduction Over the past few years

  15. Virtual Putty: Reshaping the Physical Footprint of Virtual Machines

    Microsoft Academic Search

    Jason Sonnek; Abhishek Chandra

    Virtualization is a key technology underlying cloud computing platforms, where applications encapsulated within virtual machines are dynamically mapped onto a pool of physical servers. In this paper, we argue that cloud providers can significantly lower operational costs, and improve hosted application performance, by accounting for affinities and conflicts between co-placed virtual machines. We show how these affinities can be in-

  16. Petrological and geochronological constraints on the metamorphic evolution of high-pressure granulites and eclogites of the Snowbird tectonic zone, Canada

    E-print Network

    Baldwin, Julia A. (Julia Ann), 1974-

    2003-01-01

    This thesis examines the petrology and geochronology of high-pressure granulites and eclogites within the Snowbird tectonic zone of the western Canadian Shield. The focus of this study is the East Athabasca mylonite triangle ...

  17. Virtual reality welder training

    NASA Astrophysics Data System (ADS)

    White, Steven A.; Reiners, Dirk; Prachyabrued, Mores; Borst, Christoph W.; Chambers, Terrence L.

    2010-01-01

    This document describes the Virtual Reality Simulated MIG Lab (sMIG), a system for Virtual Reality welder training. It is designed to reproduce the experience of metal inert gas (MIG) welding faithfully enough to be used as a teaching tool for beginning welding students. To make the experience as realistic as possible it employs physically accurate and tracked input devices, a real-time welding simulation, real-time sound generation and a 3D display for output. Thanks to being a fully digital system it can go beyond providing just a realistic welding experience by giving interactive and immediate feedback to the student to avoid learning wrong movements from day 1.

  18. Virtual-Geology.Info

    NSDL National Science Digital Library

    At virtual-geology.info, Roger Suthren, a professor at Oxford Brookes University, offers educational materials on geologic phenomena throughout the world. Users can take virtual field trips to study the geology of Scotland, Alaska, and France. In the Regional Geology link, visitors can view wonderful pictures of the volcanoes of Germany, Italy, France, and Greece. Educators can find images of sediments and sedimentary rocks which can be used in a variety of classroom exercises. The website supplies descriptions and additional educational links about sedimentology and environmental geology.

  19. A VIRTUAL OPERATING SYSTEM

    SciTech Connect

    Hall, Dennis E.; Scherrer, Deborah K.; Sventek, Joseph S.

    1980-05-01

    Significant progress toward disentangling computing environments from their under lying operating systern has been made. An approach is presented that achieves inter-system uniformity at all three levels of user interface - virtual machine, utilities, and command language. Under specifiable conditions, complete uniformity is achievable without disturbing the underlying operating system. The approach permits accurate computation of the cost to move both people and software to a new system. The cost of moving people is zero, and the cost of moving software is equal to the cost of implementing a virtual machine. Efficiency is achieved through optimization of the primitive functions.

  20. Astrophysical Virtual Observatory

    NSDL National Science Digital Library

    At this website, the European Commission and six European organizations discuss the creation of the Astrophysical Virtual Observatory Project (AVO) for European astronomy. Visitors can discover the function of a Virtual Observatory (VO) as "an international astronomical community-based initiative" aimed at allowing "global electronic access to the available astronomical data archives of space and ground-based observatories." Users can learn about the current problems associated with combining astronomical data collected all over the world and how a VO can streamline this data. The website supplies numerous images illustrating galactic scenarios, AVO prototypes, and AVO goals.

  1. Virtual Finance Library

    NSDL National Science Digital Library

    Search Partners, a provider of executive financial search services, presents the Virtual Finance Library, a packed collection of links to financial sites. The main page of Virtual Finance Library contains general information including reference and dictionary sites, calculators and converters, and interesting links. The rest of the library is accessible via the table of contents on the left side of the screen. The Websites are organized by topic, geographic location, or subtopic. Each topic begins with a short introduction to the subject, several pages long, and most links are descriptively annotated.

  2. A frameless stereotaxic operating microscope for neurosurgery

    Microsoft Academic Search

    E. M. Friets; J. W. Strohbehn; J. F. Hatch; D. W. Roberts

    1989-01-01

    A new system, which we call the frameless stereotaxic operating microscope, is discussed. Its purpose is to display CT or other image data in the operating microscope in the correct scale, orientation, and position without the use of a stereotaxic frame. A nonimaging ultrasonic rangefinder allows the position of the operating microscope and the position of the patient to be

  3. Microscopic Analysis of Activated Sludge. Training Manual.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This training manual presents material on the use of a compound microscope to analyze microscope communities, present in wastewater treatment processes, for operational control. Course topics include: sampling techniques, sample handling, laboratory analysis, identification of organisms, data interpretation, and use of the compound microscope.…

  4. Thermoreflectance based thermal microscope James Christoffersona

    E-print Network

    Thermoreflectance based thermal microscope James Christoffersona and Ali Shakouri Jack Baskin microscope has been built which achieves 34 mK resolution for real time 1 s frames, and 0.34 K resolution is used as the basis for the thermal imag- ing microscope. This system exhibits a speedup factor of 256

  5. Inverted Fluorescent Microscope Procedure Taking an Image

    E-print Network

    Inverted Fluorescent Microscope Procedure Taking an Image 1. Load the program "QCapture Pro" 2 on the White Light Source using the button on the main body of the microscope (it is coordinate with the box. Click on the "Preview" Tab. 8. Click on "Start Preview" to get a live feed from the Microscope. 9

  6. Cryogenic magnetic force microscope M. Rosemana)

    E-print Network

    Grütter, Peter

    Cryogenic magnetic force microscope M. Rosemana) and P. Gru¨tter Centre for the Physics for publication 27 June 2000 We describe our cryogenic magnetic force microscope, operating between 4.2 and 300 K. As an effective means of vibration isolation, we suspend the microscope from a soft bellows which attenuates

  7. Virtual reality for emergency training

    SciTech Connect

    Altinkemer, K. [Purdue Univ., West Lafayette, IN (United States). Krannert Graduate School of Management

    1995-12-31

    Virtual reality is a sequence of scenes generated by a computer as a response to the five different senses. These senses are sight, sound, taste, touch, smell. Other senses that can be used in virtual reality include balance, pheromonal, and immunological senses. Many application areas include: leisure and entertainment, medicine, architecture, engineering, manufacturing, and training. Virtual reality is especially important when it is used for emergency training and management of natural disasters including earthquakes, floods, tornados and other situations which are hard to emulate. Classical training methods for these extraordinary environments lack the realistic surroundings that virtual reality can provide. In order for virtual reality to be a successful training tool the design needs to include certain aspects; such as how real virtual reality should be and how much fixed cost is entailed in setting up the virtual reality trainer. There are also pricing questions regarding the price per training session on virtual reality trainer, and the appropriate training time length(s).

  8. Virtual-Channel Flow Control

    Microsoft Academic Search

    William J. Dally

    1992-01-01

    Abstract Network throughput,can be increased by dividing the buffer storage associated with each network channel into several virtual channels [DalSei]. Each physical channel is associated with several small queues, virtual channels, rather than a single deep queue. The virtual channels associated with one physical channel,are allocated in- dependently,but compete,with each other for physical bandwidth.,Virtual channels,decouple,buffer resources from transmission resources. This

  9. Mineralogic and Petrologic Overview of Core Samples From the Dept. of Energy's Western Gas Sands Project Multiwell Experiment, Piceance Basin, Colorado

    Microsoft Academic Search

    M. O. Eatough

    1983-01-01

    The Petrology Laboratory of Bendix Field Engineering Corporation (BFEC) at Grand Junction, Colorado, is performing mineralogic and petrologic analyses on core samples from the Multi-Well Experiment (MWX) project for Sandia National Laboratories. The samples studied to date include some fluvial sands, transitional sands, and shoreline blanket sands. The sands are generally fine-grained feldspar and lithic-rich quartz sandstones, with minimal textural

  10. Petrology and geochemistry of lithic fragments separated from the Apollo 15 deep-drill core

    NASA Technical Reports Server (NTRS)

    Lindstrom, M. M.; Nielsen, R. L.; Drake, M. J.

    1977-01-01

    Petrological and geochemical analysis of lithic fragments separated from the Apollo 15 deep-drill core showed these fragments to fall into the essentially the same range of rock types as observed in surface soil samples and large rock samples. Three particles are singled out as being of special interest. One sample is a mare basalt containing extremely evolved phases. The particle may represent small-scale imperfect crystal/liquid separation in a lava flow. A green glass particle is not the ultramafic emerald green glass described from the Apollo 15 site, but rather an ANT-like light green color, and has a quite different chemical composition from the ultramafic variety. One mare basalt displays a positive Eu anomaly and is enriched in plagioclase relative to olivine plus pyroxene.

  11. Petrologic monitoring of 1981 and 1982 eruptive products from mount st. Helens.

    PubMed

    Cashman, K V; Taggart, J E

    1983-09-30

    New material from the dacite lava dome of Mount St. Helens, collected soon after the start of each successive extrusion, is subjected to rapid chemical and petrologic analysis. The crystallinity of the dacite lava produced in 1981 and 1982 is 38 to 42 percent, about 10 percent higher than for products of the explosive 1980 eruptions. This increase in crystallinity accompanies a decrease in the ratio of hornblende to hornblende plus orthopyroxene, which suggests that the volatile-rich, crystal-poor material explosively erupted in 1980 came from the top of a zoned magma chamber and that a lower, volatile-poor and crystal-rich region is now being tapped. The major-element chemistry of the dacite lava has remained essentially constant (62 to 63 percent silica) since August 1980, ending a trend of decreasing silica seen in the products of the explosive eruptions of May through August 1980. PMID:17759011

  12. The petrology, geochemistry and petrogenesis of the Edough igneous rocks, Annaba, NE Algeria

    NASA Astrophysics Data System (ADS)

    Ahmed-Said, Y.; Leake, B. E.; Rogers, G.

    1993-07-01

    Microgranites and rhyolites of the Edough complex, Annaba, NE Algeria are described. Their petrology and geochemistry indicate that these calc-alkaline, probable Tertiary rocks, evolved by feldspar-dominated fractional crystallization of a basic magma. Trace elements and isotopic ratios of Sr ( 87Sr/ 86Sr 16.0 = 0.71947-0.72404) and detailed petrogenetic modelling exclude the granites from being produced solely by simple crystal fractionation of a basaltic magma and the similarities of these ratios to those of the Edough biotite gneisses ( 87Sr/ 86Sr 16.0 = 0.71840-0.73008) confirm a genetic link. We conclude that the Edough Tertiary magmatic rocks and perhaps many of the Tertiary igneous rocks of NE Algeria were produced by crystal fractionation of mantle-derived basaltic magma which subsequently assimilated substantial amounts of crustal material of the type Edough biotite gneisses.

  13. Petrology and provenance of the Great Valley Group. Southern Klamath Mountains and northern Sacramento Valley

    SciTech Connect

    Short, P.F.; Ingersoll, R.V. (Univ. of California, Los Angeles (USA))

    1990-05-01

    Lower Cretaceous sandstone and conglomerate of the Great Valley Group rest depositionally on the southern Klamath Mountains at the north end of the Sacramento Valley. Exposures include nonmarine, shallow marine, and deep marine sediments, which are part of the Platina Formation (petrofacies). Approximately 150 sandstone point counts (500 points per section using Gazzi-Dickinson method) and 32 conglomerate clast counts indicate a Klamath provenance of mixed magmatic-arc and recycled orogenic character. Standard triangular plots and multivariate analyses (combined with paleocurrent and paleogeographic data) suggest discrete source areas within the Klamath terrane. However, the general homogeneity of both sandstone and conglomerate petrology is consistent with all of the units being included within the Platina petrofacies.

  14. Geochemical and petrological sampling and studies at the first moon base

    NASA Technical Reports Server (NTRS)

    Haskin, L. A.; Korotev, R. L.; Lindstrom, D. J.; Lindstrom, M. M.

    1985-01-01

    Strategic sampling appropriate to the first-order lunar base can advance a variety of first-order lunar geochemical and petrological problems. Field observation and collection of samples would be done on the lunar surface, but detailed analysis would be done mainly in terrestrial laboratories. Among the most important areas of investigation for which field observations can be made and samples can be collected at the initial base are regolith studies, studies of mare and highlands stratigraphy, and a search for rare materials such as mantle nodules. Since the range of exploration may be limited to a radius of about 20 km from the first lunar base, locating the base near a mare-highlands boundary would enable the greatest latitude in addressing these problems.

  15. An Automated Virtualization Performance Analysis Platform

    Microsoft Academic Search

    Kyle E Stewart; Jeffrey W Humphries; Todd R Andel

    2012-01-01

    This research compares three traditional categories of virtualization to a technique known as hybrid virtualization. Each technique is evaluated in terms of both capability and performance. The traditional methods of platform virtualization such as full virtualization, paravirtualization and operating system virtualization each comes with its own set of capabilities and engineering trade-offs. Hybrid virtualization attempts to leverage the benefits of

  16. Parallel techniques for Virtual Cell

    Microsoft Academic Search

    Sanguthevar Rajasekaran; Reda Ammar; B. Cheriyan; L. Loew

    2004-01-01

    The Virtual Cell is a simulation package created by the National Resource for Cell Analysis and Modeling (NRCAM). It enables users to model cell biological processes [J.C. Schaff et al. (2001)]. The core of the Virtual Cell is solving a system of PDEs. Sequential runs of the Virtual Cell can take large amounts of time and hence parallelization is needed.

  17. What Is a Virtual School?

    ERIC Educational Resources Information Center

    Tuttle, Harry G.

    1998-01-01

    Describes six models of virtual schools which use e-mail, online chats, Internet resources, and archived resources to teach courses. Discusses advantages and limitations of virtual schools, and presents some questions for evaluating them. A sidebar lists 10 virtual school Web sites. (AEF)

  18. Virtual Economies: Threats and Risks

    NASA Astrophysics Data System (ADS)

    Thorpe, Christopher; Hammer, Jessica; Camp, Jean; Callas, Jon; Bond, Mike

    In virtual economies, human and computer players produce goods and services, hold assets, and trade them with other in-game entities, in the same way that people and corporations participate in "real-world" economies. As the border between virtual worlds and the real world grows more and more permeable, privacy and security in virtual worlds matter more and more.

  19. Constructing Meaning with Virtual Reality.

    ERIC Educational Resources Information Center

    Iaonnou-Georgiou, Sophie

    2002-01-01

    Presents a constructivist rationale for introducing virtual reality in language learning and teaching and describes various virtual reality environments that are available. Ways of implementing constuctivist learning through virtual reality are suggested as well as basic guidelines for successful implementation in the classroom. (Author/VWL)

  20. A Virtual Assembly Design Environment

    Microsoft Academic Search

    Sankar Jayaram; Yong Wang; Uma Jayaram; Kevin W. Lyons; Peter Hart

    1999-01-01

    The Virtual Assembly Design Environment (VADE) is a Virtual Reality (VR)-based engineering application that allows engineers to evaluate, analyze, and plan the assembly of mechanical systems. This system focuses on utilizing an immersive, virtual environment tightly coupled with commercial computer aided design (CAD) systems. Salient features of VADE include: 1) data integration (two-way) with a parametric CAD system, 2) realistic

  1. Leading Virtual Teams: Three Cases

    ERIC Educational Resources Information Center

    Johnson, James R.; Jeris, Laurel

    2004-01-01

    This study investigated virtual team members' and leaders' perceptions of the role of the leader, and hindering and helping forces within virtual teams and their host organizations for developing leaders of such teams. It addresses the expressed need of virtual team leaders for the field of HRD to guide leadership development for this emerging…

  2. Virtual Worlds in Computing Education

    ERIC Educational Resources Information Center

    Crellin, Jonathan; Duke-Williams, Emma; Chandler, Jane; Collinson, Timothy

    2009-01-01

    This article reports on the use of a virtual world ("Second Life") in computing education, and identifies the precursors of current virtual world systems. The article reviews the potential for virtual worlds as tools in computing education. It describes two areas where "Second Life" has been used in computing education: as a development…

  3. Ethnography in a Virtual World

    ERIC Educational Resources Information Center

    Shumar, Wesley; Madison, Nora

    2013-01-01

    This article situates the discussion of virtual ethnography within the larger political/economic changes of twenty-first century consumer capitalism and suggests that increasingly our entire social world is a virtual world and that there were very particular utopian and dystopian framings of virtual community growing out of that history. The…

  4. Report on State Virtual Schools

    ERIC Educational Resources Information Center

    Southern Regional Education Board (SREB), 2005

    2005-01-01

    This report on state virtual schools outlines the recent trends associated with virtual high schools over the last 15 years. It notes that early trends indicate that virtual schools are on the rise. The report provides reasons for why the trends have occurred, and describes the Southern Regional Education Board's role in providing information and…

  5. Virtual Environments for Corporate Education

    E-print Network

    -1-61520-620-9 (ebook) 1. Virtual reality in management. 2. Employees-- Training of. 3. Virtual reality in education. IVirtual Environments for Corporate Education: Employee Learning and Solutions William Ritke of the trademark or registered trademark. Library of Congress Cataloging-in-Publication Data Virtual environments

  6. Basaltic Magmatism: The Dominant Factor in the Petrologic and Tectonic Evolution of the Earth

    NASA Technical Reports Server (NTRS)

    Lowman, Paul D., Jr.

    2003-01-01

    Silicate bodies such as the Moon, Mars, probably Mercury, and possibly Venus, appear to have evolved in three main stages: a first (felsic) differentiation, a late heavy bombardment, and a second (basaltic) differentiation. It has been proposed that the Earth underwent a similar sequence. This paper argues that the second differentiation, basaltic magmatism, has dominated the petrologic and tectonic evolution of the Earth for four billion years. A global andesitic crust, formed during and after accretion of the planet, was disrupted by major impacts that triggered mantle upwelling and sea-floor spreading about 4 billion years ago. The oceanic crust collectively has since been formed by basaltic volcanism, from spreading centers and mantle plumes. However, the continental crust has also been greatly affected. Basaltic underplating has promoted anatexis and diapiric intrusion of granitoids in granite-greenstone terrains, as well as providing heat for regional metamorphism. Basaltic intrusions, such as the Nipissing diabase of the Sudbury area, have added to the thickness of continental crust. Satellite magnetic surveys suggest that there are more such basaltic intrusions than previously realized; examples include the Bangui anomaly of central Africa and the Kentucky anomaly. Basaltic overplating from mafic dike swarms has repeatedly flooded continents; had it not been for erosion, they would be covered with basalt as Venus is today. The tectonic effects of basaltic volcanism on continents have only recently been realized. The World Stress Map project has discovered that continents are under horizontal compressive stress, caused by push from mid-ocean ridges, i.e., by basaltic volcanism. The stress fields are generally uniform over large intraplate areas, and could contribute to intraplate tectonism. Seafloor spreading has demonstrably been effective for at least 200 million years, and ridge push thus a contributor to tectonic activity for that long. Collectively, the petrologic and tectonic evolution of the Earth has been dominated for about 4 billion years by the 'second differentiation,' i.e., by basaltic magmatism.

  7. Petrological-thermomechanical modeling of Precambrian continental collision: geodynamical effects of subcontinental lithospheric mantle thickness

    NASA Astrophysics Data System (ADS)

    Zakharov, Vladimir; Perchuk, Alexei; Zavyalov, Sergei; Sineva, Tamara; Gerya, Taras

    2015-04-01

    The Precambrian collision and orogeny remains enigmatic and contentious. Different tectonic styles of orogeny in the Precambrian compared to modern Earth are suggested by interpretations of geological, petrological and geochemical observations from Proterozoic and Archean orogenic belts. Here, we present results of 2D petrological-thermomechanical numerical modeling of continental collision at crustal thickness of 35 km and convergence rate of 5 cm/year with variable thickness of subcontinental lithospheric mantle (SCLM). The numerical experiments cover the range of SCLM thickness from 65 km to 165 km, the upper mantle temperature exceeded the modern temperature by 150 oC, and the radiogenic heat production of continental crust is 1.5 times higher than that at present. The numerical modeling has shown that in the case of SCLM thickness of 65 to 125 km the subduction terminates with slab break-off followed by the formation of a large igneous province in between the two continents instead of an orogenic belt. The time and the place of the slab break-off depend on SCLM thickness. The thinner it is, the earlier and the closer to the surface the slab breaks-off. For instance, the slab is detached in 10.3 m.y. at the depth 150 km when the model with SCLM of 115 km, whereas in the case of SCLM of 65 km the slab detaches in 5.1 m.y. almost near the very surface. In the latter case, the magmatic province is very large due to development at the both sides of the oceanic slab (instead of one side provinces in the other experiments). Continental collision with a very thick SCLM (of 165 km and more) proceeds without slab break-off and rather limited volcanism. This work was supported by the Russian Foundation for Basic Research, grant 13-05-01033 and by the Supercomputing Centre of Lomonosov Moscow State University.

  8. The distinct morphological and petrological features of shock melt veins in the Suizhou L6 chondrite

    NASA Astrophysics Data System (ADS)

    Xie, Xiande; Sun, Zhenya; Chen, Ming

    2011-03-01

    The morphology and petrology of distinct melt veins in the Suizhou L6 chondrite have been investigated using scanning electron microscopy, electron microprobe analyses, and Raman spectroscopy, synchrotron energy-dispersive diffraction, and transmission electron microscopy. It is found that the melt veins in the Suizhou meteorite morphologically are the simplest, straightest, and thinnest among all shock veins known from meteorites. At first glance, these veins look like fine fractures, but petrologically they are solid melt veins of chondritic composition and consist of fully crystalline materials of two distinct lithological assemblages, with no glassy material remaining. The Suizhou melt veins contain the most abundant high-pressure mineral species when compared with all other veins known in chondrites. Thus, these veins in Suizhou are classified as shock veins. All rock-forming and almost all accessory minerals in the Suizhou shock veins have been transformed to their high-pressure polymorphs, and no fragments of the precursor minerals remain in the veins. Among the 11 high-pressure mineral phases identified in the Suizhou veins, three are new high-pressure minerals, namely, tuite after whitlockite, xieite, and the CF phase after chromite. On the basis of transformation of plagioclase into maskelynite, it is estimated that the Suizhou meteorite experienced shock pressures and shock temperatures up to 22 GPa and 1000 °C, respectively. Shearing and friction along shock veins raised the temperature up to 1900-02000 °C and the pressure up to 24 GPa within the veins. Hence, phase transition and crystallization of high-pressure minerals took place only in the Suizhou shock veins. Fast cooling of the extremely thin shock veins is regarded as the main reason that up to 11 shock-induced high-pressure mineral phases could be preserved in these veins.

  9. Potential contributions of metamorphic petrology studies in an ultra-deep drillhole in the southern Appalachians

    SciTech Connect

    Speer, J.A.

    1985-01-01

    The proposed, ultra-deep hole in the southeast U.S. will penetrate allochthonous, medium- to high-grade metamorphic rocks of the Inner Piedmont and Blue Ridge thrust sheets. It is anticipated that the hole will then encounter autochthonous low-grade, metasedimentary cover rocks before bottoming out in crystalline Precambrian basement rocks. Metamorphic petrology in the recent past has concentrated on unraveling the physical and chemical history (P, T, X/sub fluid/, etc.) of metamorphic rocks. The techniques that have been developed are ideally suited to the study of relatively limited samples from drill core. Detailed studies of the allochthonous and autochthonous rocks from the drillhole, combined with comparable studies of the surface rocks, by metamorphic petrologists experimented with these approaches, would give a 3-dimensional picture of the PTX evolution in the region of the ultra-deep hole, and thus an idea of the geometrical, chemical, and physical changes the rocks experienced. This would place constraints on conditions of the rocks before and after thrusting and thus any tectonic models of thrusting in the southern Appalachians. With limited sampling this could be a problem, with more complete sampling it will be an advantage. The metamorphic petrology of the rocks will provide basic support for the other studies of the drill core and drillhole, most notably geochronology and stable isotopes. It should not be forgotten that in addition to the historical metamorphism, the expected, present-day conditions in the drillhole are those of burial metamorphism. The hole will present an excellent opportunity to study such active metamorphic conditions.

  10. The Distant Morphological and Petrological Features of Shock Melt Veins in the Suizhou L6 Condrite

    SciTech Connect

    X Xie; Z Sun; M Chen

    2011-12-31

    The morphology and petrology of distinct melt veins in the Suizhou L6 chondrite have been investigated using scanning electron microscopy, electron microprobe analyses, and Raman spectroscopy, synchrotron energy-dispersive diffraction, and transmission electron microscopy. It is found that the melt veins in the Suizhou meteorite morphologically are the simplest, straightest, and thinnest among all shock veins known from meteorites. At first glance, these veins look like fine fractures, but petrologically they are solid melt veins of chondritic composition and consist of fully crystalline materials of two distinct lithological assemblages, with no glassy material remaining. The Suizhou melt veins contain the most abundant high-pressure mineral species when compared with all other veins known in chondrites. Thus, these veins in Suizhou are classified as shock veins. All rock-forming and almost all accessory minerals in the Suizhou shock veins have been transformed to their high-pressure polymorphs, and no fragments of the precursor minerals remain in the veins. Among the 11 high-pressure mineral phases identified in the Suizhou veins, three are new high-pressure minerals, namely, tuite after whitlockite, xieite, and the CF phase after chromite. On the basis of transformation of plagioclase into maskelynite, it is estimated that the Suizhou meteorite experienced shock pressures and shock temperatures up to 22 GPa and 1000 C, respectively. Shearing and friction along shock veins raised the temperature up to 1900-2000 C and the pressure up to 24 GPa within the veins. Hence, phase transition and crystallization of high-pressure minerals took place only in the Suizhou shock veins. Fast cooling of the extremely thin shock veins is regarded as the main reason that up to 11 shock-induced high-pressure mineral phases could be preserved in these veins.

  11. Petrologic considerations for hot dry rock geothermal site selection in the Clear Lake Region, California

    SciTech Connect

    Stimac, J.; Goff, F. (Los Alamos National Lab., NM (United States)); Hearn, B.C. Jr. (US Geological Survey, Reston, VA, Branch of Lithospheric Processes (United States))

    1992-01-01

    The Clear Lake area is well known for anomalous heat flow, thermal springs, hydrothermal mineral deposits, and Quaternary volcanism. These factors, along with the apparent lack of a large reservoir of geothermal fluid north of Collayomi fault make the Clear Lake area an attractive target for hot dry rock (HDR) geothermal development. Petrologic considerations provide some constraints on site selection for HDR development. Spatial and temporal trends in volcanism in the Coast Ranges indicate that magmatism has migrated to the north with time, paralleling passage of the Mendocino triple junction and propagation of the San Andreas fault. Volcanism in the region may have resulted from upwelling of hot asthenosphere along the southern margin of the subducted segment of the Gorda plate. Spatial and temporal trends of volcanism within the Clear Lake volcanic field are similar to larger-scale trends of Neogene volcanism in the Cost Ranges. Volcanism (especially for silicic compositions) shows a general migration to the north over the {approximately}2 Ma history of the field, with the youngest two silicic centers located at Mt. Konocti and Borax Lake. The Mt. Konocti system (active from {approximately} 0.6 to 0.3 Ma) was large and long-lived, whereas the Borax Lake system is much smaller but younger (0.09 Ma). Remnants of silicic magma bodies under Mt. Konocti may be in the latter stages of cooling, whereas a magma body centered under Borax Lake may be in the early stages of development. The existence of an upper crustal silicic magma body of under Borax Lake has yet to be demonstrated by passive geophysics, however, subsurface temperatures in the area as high (> 200{degrees}C at 2000 m) as those beneath the Mt. Konocti area. Based on petrologic considerations alone, the Mt. Konocti-Borax Lake area appears to be the most logical choice for HDR geothermal development in the region.

  12. Virtual Human Project

    Microsoft Academic Search

    R. C. Ward; K. L. Kruse; G. O. Allgood; L. M. Hively; K. N. Fischer; N. B. Munro; C. E. Easterly

    This paper describes the development of a comprehensive human modeling environment, the Virtual Human, which will be used initially to model the human respiratory system for purposes of predicting pulmonary disease or injury using lung sounds. The details of the computational environment, including the development of a V irtual Human Thorax, a database for storing models, model parameters, and experimental

  13. Virtual machine performance benchmarking.

    PubMed

    Langer, Steve G; French, Todd

    2011-10-01

    The attractions of virtual computing are many: reduced costs, reduced resources and simplified maintenance. Any one of these would be compelling for a medical imaging professional attempting to support a complex practice on limited resources in an era of ever tightened reimbursement. In particular, the ability to run multiple operating systems optimized for different tasks (computational image processing on Linux versus office tasks on Microsoft operating systems) on a single physical machine is compelling. However, there are also potential drawbacks. High performance requirements need to be carefully considered if they are to be executed in an environment where the running software has to execute through multiple layers of device drivers before reaching the real disk or network interface. Our lab has attempted to gain insight into the impact of virtualization on performance by benchmarking the following metrics on both physical and virtual platforms: local memory and disk bandwidth, network bandwidth, and integer and floating point performance. The virtual performance metrics are compared to baseline performance on "bare metal." The results are complex, and indeed somewhat surprising. PMID:21207096

  14. Learning in Virtual Reality.

    ERIC Educational Resources Information Center

    Bricken, William

    The essence of the computer revolution is yet to come, for computers are essentially generators of realities. Virtual reality (VR) is the next step in the evolutionary path; the user is placed inside the image and becomes a participant within the computational space. A VR computer generates a direct experience of the computational environment. The…

  15. Virtual Field Trips.

    ERIC Educational Resources Information Center

    Walter, Virginia A.

    1997-01-01

    Virtual field trips can provide experiences beyond the reach of average K-12 students. Describes multimedia products for school use: Africa Trail, Dinosaur Hunter, Louvre Museum, Magic School Bus Explores the Rainforest, and Up to the Himalayas: Kingdoms in the Clouds and provides book and Internet connections for additional learning, highlighting…

  16. Virtual Human Anatomy

    Microsoft Academic Search

    Lin Yong; J. X. Chen; Yanling Liu

    2005-01-01

    To learn human anatomy, medical students must practice on cadavers, as must physicians when they want to brush up on their anatomy knowledge. However, cadavers are in short supply in medical schools worldwide. One potential solution to this problem is the virtual human anatomy and surgery system. VHASS uses cryosection images - cross-section natural-color images generated by slicing a frozen

  17. Virtual Cardiology Lab

    NSDL National Science Digital Library

    Joseph Perpich, M.D., J.D. (Howard Hughes Medical Institute; )

    2008-04-16

    The focus of this lab is on heritable diseases of the heart. You are cast here as a virtual intern to accompany a doctor examining three different patients. Each patient is examined, using more than one diagnostic tool, and at each stage, the doctor will invite you to examine the patient yourself and ask for your opinion.

  18. Virtual Libraries: Service Realities.

    ERIC Educational Resources Information Center

    Novak, Jan

    This paper discusses client service issues to be considered when transitioning to a virtual library situation. Themes related to the transitional nature of society in the knowledge era are presented, including: paradox and a contradictory nature; blurring of boundaries; networks, systems, and holistic thinking; process/not product, becoming/not…

  19. Adventures in Virtual Reality

    NSDL National Science Digital Library

    In this activity, students look at the topography and cross-section of El Paso Texas and Edwards Aquifer in virtual reality, using historical data of the Edwards Aquifer that contains information on recharge, discharge and precipitation. From this data, conclusions can be made about future discharges of the aquifer.

  20. Virtual Seismic Atlas

    NSDL National Science Digital Library

    Virtual Seismic Atlas

    The Virtual Seismic Atlas is an open access community resource to share the geological interpretation of seismic data. By browsing freely through the site you will find seismic images and interpretations. And you can down load higher resolution images for your use.

  1. War Games Go Virtual

    ERIC Educational Resources Information Center

    Carlson, Scott

    2006-01-01

    This article describes how researchers work with military to create the next generation of training technology. This article also describes the features of Flatworld, a virtual military training technology. Flatworld is one of many projects under development at the Institute for Creative Technologies, a research group that is supported primarily…

  2. Energy Savers Virtual Home

    NSDL National Science Digital Library

    This web-based computer simulation allows the participant to calculate energy savings in various types of virtual residential dwellings by making changes in the appliances, light bulbs, insulation, energy sources, etc. that are used. This is a totally interactive simulation that would be suitable for junior high school through college classes. This simulation also contains links where students can access research information.

  3. Optimizing Embedded Virtual Machines

    Microsoft Academic Search

    Joel Koshy; Raju Pandey; Ingwar Wirjawan

    2009-01-01

    Virtual machines (VMs) play an important role in mainstream computing by enabling interoperability, security, and higher levels of abstraction. Their use in embedded computing systems is deterred primarily by the resource constraints of embedded microcontrollers. In this paper, we show how various optimizations can significantly decrease these overheads, making VMs viable as system software for even low-end (8- or 16-bit)

  4. Virtual Tide Pool

    NSDL National Science Digital Library

    Science NetLinks (PBS; )

    2003-04-29

    Virtual Tide Pool features a three dimensional view of a tide pool during both low and high tides. Students can see animals that live under, above, and at the waters surface. This site offers the ability to pan the tide pool for a 360 degree view, with zoom options, and gives descriptions of the animals found during both low and high tides.

  5. Interactive Virtual Environments Introduction

    E-print Network

    Petriu, Emil M.

    - visual, auditory, haptic or other nature - sensor-based and/or synthetic models of 3D objects the virtual environment. This technology has already found promising applications in industry, communications, tele-robotics, medicine and healthcare, security and entertainment. #12;The first part of the course

  6. Virtual Bridge Design Challenge

    ERIC Educational Resources Information Center

    Mitts, Charles R.

    2013-01-01

    This design/problem-solving activity challenges students to design a replacement bridge for one that has been designated as either structurally deficient or functionally obsolete. The Aycock MS Technology/STEM Magnet Program Virtual Bridge Design Challenge is an authentic introduction to the engineering design process. It is a socially relevant…

  7. Evolving virtual creatures

    Microsoft Academic Search

    Karl Sims

    1994-01-01

    This paper describes a novel system for creating virtual creatures that move and behave in simulated three-dimensional physical worlds. The morphologies of creatures and the neural systems for controlling their muscle forces are both generated automatically using genetic algorithms. Different fitness evaluation functions are used to direct simulated evolutions towards specific behaviors such as swimming, walking, jumping, and following.A genetic

  8. Virtual Bead Loom

    NSDL National Science Digital Library

    This site uses the example of Native American beadwork to demonstrate mathematical concepts (specifically, Cartesian coordinates). The materials include an interactive virtual beadloom with which students can create their own beadwork design. The interdisciplinary lesson may be used in conjunction with instruction on Native American culture and traditions.

  9. A Virtual, Shoestring Vacation

    NSDL National Science Digital Library

    Juliana Texley

    2009-07-01

    If there is a discrepancy between the scope of your imagination and the depth of your bank account, this may be the ideal summer to stretch your horizons by diving into a good book. You can take a virtual vacation to almost any place or time by reading. Y

  10. Virtual Inquiry Experiences

    ERIC Educational Resources Information Center

    Harlow, Danielle; Nilsen, Katy

    2011-01-01

    Children in classrooms and scientists in laboratories engage in similar activities: they observe, ask questions, and try to explain phenomena. Video conferencing technology can remove the wall between the classroom and the laboratory, bringing children and scientists together. Virtual experiences and field trips can provide many of the benefits of…

  11. Virtual Coin Toss

    NSDL National Science Digital Library

    2008-01-01

    Have you ever wondered what would happen if you tossed a coin one hundred times? What about 1,000? What about 10,000? Would you end up with more heads or more tails? Cyberspace has made it easy for you to find out using their virtual coin toss machine. This site is very helpful when studying probability!

  12. The Virtual Clinical Campus.

    ERIC Educational Resources Information Center

    Friedman, Charles P.

    1996-01-01

    To provide medical students in community-based clinical settings with access to the same range of educational resources (medical literature, student colleagues, feedback, faculty) available at the academic medical center, this paper proposes that advancing information technology be applied to create a "virtual clinical campus" in the community…

  13. The virtual time machine

    Microsoft Academic Search

    Richard M. Fujimoto

    1989-01-01

    A parallel computer architecture is proposed that is based on an optimistic style of execution. Specifically, the Virtual Time Machine (VTM) detects violations of data depen- dence constraints at runtime, and automatically recovers from them. In order to efficiently implement this mecha- nism, a sophisticated, two-dimensional memory system is proposed that is addressed using both a spatial and a tern.

  14. Virtual environments in neuroscience

    Microsoft Academic Search

    Giuseppe Riva

    1998-01-01

    Virtual environments (VEs) let users navigate and interact with computer generated three dimensional (3D) environments in real time, allowing for the control of complex stimuli presentation. These VEs have attracted much attention in medicine, especially in remote or augmented surgery, and surgical training, which are critically dependent on hand-eye coordination. Recently, however, some research projects have begun to test the

  15. Virtual Sensor Test Instrumentation

    NASA Technical Reports Server (NTRS)

    Wang, Roy

    2011-01-01

    Virtual Sensor Test Instrumentation is based on the concept of smart sensor technology for testing with intelligence needed to perform sell-diagnosis of health, and to participate in a hierarchy of health determination at sensor, process, and system levels. A virtual sensor test instrumentation consists of five elements: (1) a common sensor interface, (2) microprocessor, (3) wireless interface, (4) signal conditioning and ADC/DAC (analog-to-digital conversion/ digital-to-analog conversion), and (5) onboard EEPROM (electrically erasable programmable read-only memory) for metadata storage and executable software to create powerful, scalable, reconfigurable, and reliable embedded and distributed test instruments. In order to maximize the efficient data conversion through the smart sensor node, plug-and-play functionality is required to interface with traditional sensors to enhance their identity and capabilities for data processing and communications. Virtual sensor test instrumentation can be accessible wirelessly via a Network Capable Application Processor (NCAP) or a Smart Transducer Interlace Module (STIM) that may be managed under real-time rule engines for mission-critical applications. The transducer senses the physical quantity being measured and converts it into an electrical signal. The signal is fed to an A/D converter, and is ready for use by the processor to execute functional transformation based on the sensor characteristics stored in a Transducer Electronic Data Sheet (TEDS). Virtual sensor test instrumentation is built upon an open-system architecture with standardized protocol modules/stacks to interface with industry standards and commonly used software. One major benefit for deploying the virtual sensor test instrumentation is the ability, through a plug-and-play common interface, to convert raw sensor data in either analog or digital form, to an IEEE 1451 standard-based smart sensor, which has instructions to program sensors for a wide variety of functions. The sensor data is processed in a distributed fashion across the network, providing a large pool of resources in real time to meet stringent latency requirements.

  16. Atomic force microscope mediated chromatography.

    PubMed

    Anderson, M S

    2013-02-01

    An atomic force microscope (AFM) is presented as an instrument for rapid, miniaturized chromatography. The AFM is used to inject a sample, provide shear driven liquid flow over a functionalized substrate, and detect separated components. The components are then analyzed with surface enhanced Raman spectroscopy using AFM deposition of gold nanoparticles on the separated bands. This AFM mediated chromatography (AFM-MC) is demonstrated using lipophilic dyes and normal phase chemistry. A significant reduction in both size and separation time scales is achieved with 25 ?m length scale and 1 s separation times. AFM-MC has general applications to trace chemical analysis and microfluidics. PMID:23464258

  17. Integration of a Balanced Virtual Manikin in a Virtual Reality Platform aimed at Virtual Prototyping

    Microsoft Academic Search

    Antoine Rennuit; Alain Micaelli; Xavier Merlhiot; Claude Andriot; François Guillaume; Nicolas Chevassus; Damien Chablat; Patrick Chedmail

    2007-01-01

    the work presented here is aimed at introducing a virtual human controller in a virtual prototyping framework. After a brief introduction describing the problem solved in the paper, we describe the interest as for digital humans in the context of concurrent engineering. This leads us to draw a control architecture enabling to drive virtual humans in a real- time immersed

  18. Industrial applications' simulation technologies in virtual environments Part II: Virtual Manufacturing and Virtual Assembly

    E-print Network

    Aristomenis, Antoniadis

    antoniadis@chania.teicrete.gr Abstract: Virtual Reality technology when combined with the existing computer simulation environments, employing Virtual Reality technology. The characteristics of the simulation developed have been indicatively reported and the potentials of Virtual Reality technology as a simulation

  19. TECHNOLOGY APPLICATION: VIRTUAL FIELD TRIPS

    NSDL National Science Digital Library

    Mr. Hoskins

    2006-03-23

    This webquest will assist in furthering your understanding of the ins and outs of virtual fieldtrips, provide links to ready-made virtual fieldtrips, and provide a link so you can create your own virtual field trip. Virtual field trips have become increasingly popular with the extensive use of the world wide web. One reason for this is probably the ease with which this technology can be delivered. All that is required is a computer with internet access. Occasionally a virtual field trip will require some plug-ins ...

  20. Sensing mode atomic force microscope

    DOEpatents

    Hough, Paul V.; Wang, Chengpu

    2004-11-16

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  1. Martian Magnets Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit acquired this microscopic imager view of its capture magnet on sol 92 (April 6, 2004). Both Spirit and the Mars Exploration Rover Opportunity are equipped with a number of magnets. The capture magnet, as seen here, has a stronger charge than its sidekick, the filter magnet. The lower-powered filter magnet captures only the most magnetic airborne dust with the strongest charges, while the capture magnet picks up all magnetic airborne dust.

    The magnets' primary purpose is to collect the martian magnetic dust so that scientists can analyze it with the rovers' Moessbauer spectrometers. While there is plenty of dust on the surface of Mars, it is difficult to confirm where it came from, and when it was last airborne. Because scientists are interested in learning about the properties of the dust in the atmosphere, they devised this dust-collection experiment.

    The capture magnet is about 4.5 centimeters (1.8 inches) in diameter and is constructed with a central cylinder and three rings, each with alternating orientations of magnetization. Scientists have been monitoring the continual accumulation of dust since the beginning of the mission with panoramic camera and microscopic imager images. They had to wait until enough dust accumulated before they could get a Moessbauer spectrometer analysis. The results of that analysis, performed on sol 92, have not been sent back to Earth yet.

  2. Measurement in the confocal microscope.

    PubMed

    Cox, Guy

    2014-01-01

    All measurements require that the microscope must be aligned as accurately as possible, and the gain (or PMT voltage) and black level must be set to avoid any overflow or underflow. Measuring surface profiles and relative depths is straightforward and can be carried out to a higher accuracy than the depth resolution of the microscopes, even though the actual images may look poor. Measuring the thickness of objects which are labeled throughout is less accurate. Length and 2D area measurements are common image analysis problems and easily carried out with image analysis software. Volume measurements are conceptually equally simple but require manual techniques or 3D analysis software. 3D surface area measurements require specialist software, or can be carried out with stereological techniques. Fluorescence intensity measurements require careful calibration. For ratiometric measurements filters and/or laser lines should be chosen to optimize the response and calibration should be done in conditions as close as possible to the experimental ones. FLIM allows exploration of the chemical environment, and multiple labelling even where spectra overlap. When the hardware is available it is also usually the method of choice for measuring FRET, which can measure molecular interactions in the nanometer range. Without FLIM hardware, either intensity measurements with correction for bleed-through and cross talk or acceptor bleaching are the most popular methods of measuring FRET. PMID:24052358

  3. Inspection with Robotic Microscopic Imaging

    NASA Technical Reports Server (NTRS)

    Pedersen, Liam; Deans, Matthew; Kunz, Clay; Sargent, Randy; Chen, Alan; Mungas, Greg

    2005-01-01

    Future Mars rover missions will require more advanced onboard autonomy for increased scientific productivity and reduced mission operations cost. One such form of autonomy can be achieved by targeting precise science measurements to be made in a single command uplink cycle. In this paper we present an overview of our solution to the subproblems of navigating a rover into place for microscopic imaging, mapping an instrument target point selected by an operator using far away science camera images to close up hazard camera images, verifying the safety of placing a contact instrument on a sample or finding nearby safe points, and analyzing the data that comes back from the rover. The system developed includes portions used in the Multiple Target Single Cycle Instrument Placement demonstration at NASA Ames in October 2004, and portions of the MI Toolkit delivered to the Athena Microscopic Imager Instrument Team for the MER mission still operating on Mars today. Some of the component technologies are also under consideration for MSL mission infusion.

  4. Effect of display resolution on time to diagnosis with virtual pathology slides in a systematic search task.

    PubMed

    Randell, Rebecca; Ambepitiya, Thilina; Mello-Thoms, Claudia; Ruddle, Roy A; Brettle, David; Thomas, Rhys G; Treanor, Darren

    2015-02-01

    Performing diagnoses using virtual slides can take pathologists significantly longer than with glass slides, presenting a significant barrier to the use of virtual slides in routine practice. Given the benefits in pathology workflow efficiency and safety that virtual slides promise, it is important to understand reasons for this difference and identify opportunities for improvement. The effect of display resolution on time to diagnosis with virtual slides has not previously been explored. The aim of this study was to assess the effect of display resolution on time to diagnosis with virtual slides. Nine pathologists participated in a counterbalanced crossover study, viewing axillary lymph node slides on a microscope, a 23-in 2.3-megapixel single-screen display and a three-screen 11-megapixel display consisting of three 27-in displays. Time to diagnosis and time to first target were faster on the microscope than on the single and three-screen displays. There was no significant difference between the microscope and the three-screen display in time to first target, while the time taken on the single-screen display was significantly higher than that on the microscope. The results suggest that a digital pathology workstation with an increased number of pixels may make it easier to identify where cancer is located in the initial slide overview, enabling quick location of diagnostically relevant regions of interest. However, when a comprehensive, detailed search of a slide has to be made, increased resolution may not offer any additional benefit. PMID:25128321

  5. Geochemistry and petrology of Oligocene and Miocene ash-flow tuffs of the southeastern Great Basin, Nevada

    USGS Publications Warehouse

    du Bray, Edward A.

    1995-01-01

    The White River Narrows area of Southeast Nevada contains 18 regionally distributed middle Tertiary dacite to rhyolite ash-flow tuffs. Geochemical data provide an excellent opportunity to study stratigraphic and petrologic relations of these tuffs. Chemical data for each of the tuffs are distinctive and provide a significant addition to other data used to identify and correlate these units. Relatively minor compositional variation within the tuffs is noteworthy.

  6. 52. PETROLOGY OF HYDROTHERMALLY METAMORPHOSED SEDIMENTS AT DEEP SEA DRILLING SITE 477, SOUTHERN GUAYMAS BASIN RIFT, GULF OF CALIFORNIA 1

    Microsoft Academic Search

    Kerry Kelts

    At DSDP Site 477, late Quaternary diatomaceous muds and delta-derived silty-sand turbidites at 2000 meters water depth have been extensively and progressively altered by a deep-seated heat source beneath a sill. Bulk petrologic and microprobe analyses have identified a crudely zoned paragenesis within 260 meters sub-bottom which ranges from unaltered to slightly altered oozes (0-50 m), anhydrite-dolomite claystones (105-125 m),

  7. An automated system for whole microscopic image acquisition and analysis.

    PubMed

    Bueno, Gloria; Déniz, Oscar; Fernández-Carrobles, María Del Milagro; Vállez, Noelia; Salido, Jesús

    2014-09-01

    The field of anatomic pathology has experienced major changes over the last decade. Virtual microscopy (VM) systems have allowed experts in pathology and other biomedical areas to work in a safer and more collaborative way. VMs are automated systems capable of digitizing microscopic samples that were traditionally examined one by one. The possibility of having digital copies reduces the risk of damaging original samples, and also makes it easier to distribute copies among other pathologists. This article describes the development of an automated high-resolution whole slide imaging (WSI) system tailored to the needs and problems encountered in digital imaging for pathology, from hardware control to the full digitization of samples. The system has been built with an additional digital monochromatic camera together with the color camera by default and LED transmitted illumination (RGB). Monochrome cameras are the preferred method of acquisition for fluorescence microscopy. The system is able to digitize correctly and form large high resolution microscope images for both brightfield and fluorescence. The quality of the digital images has been quantified using three metrics based on sharpness, contrast and focus. It has been proved on 150 tissue samples of brain autopsies, prostate biopsies and lung cytologies, at five magnifications: 2.5×, 10×, 20×, 40×, and 63×. The article is focused on the hardware set-up and the acquisition software, although results of the implemented image processing techniques included in the software and applied to the different tissue samples are also presented. PMID:24916187

  8. Petrologic model of the northern Mississippi Embayment based on satellite magnetic and ground-based geophysical data

    NASA Technical Reports Server (NTRS)

    Thomas, H. H.

    1984-01-01

    A petrologic model of the northern Mississippi Embayment, derived from gravity, seismic and rift data, is evaluated by converting the model to a magnetization model which is compared with satellite magnetic anomaly models. A magnetization contrast of approximately -0.54 A/m, determined from the petrologic model of the embayment compares favorably to values of -0.62 A/m and -0.45 A/m from a Magsat United States Apparent Magnetization Contrast Map and a published POGO magnetization contrast model, respectively. The petrologic model suggests that the magnetic anomaly low associated with the Mississippi Embayment may be largely due to the intrusion under non-oxidizing conditions of low Curie temperature gabbroic material at the base of the crust of the embayment. Near-surface mafic plutons, bordering the Mississippi Valley Graben, appear from aeromagnetic data to have higher magnetizations than the deeper gabbroic material; however, it is impossible to ascertain if this is due to compositional differences or similar material at shallower (lower temperature) depths. These results indicate that variations in the Curie temperatures of intrusions accompanying rifting may account for a large part of the wide range of magnetic anomalies associated with presently inactive rifts with normal heat flow.

  9. Virtual reality systems

    NASA Technical Reports Server (NTRS)

    Johnson, David W.

    1992-01-01

    Virtual realities are a type of human-computer interface (HCI) and as such may be understood from a historical perspective. In the earliest era, the computer was a very simple, straightforward machine. Interaction was human manipulation of an inanimate object, little more than the provision of an explicit instruction set to be carried out without deviation. In short, control resided with the user. In the second era of HCI, some level of intelligence and control was imparted to the system to enable a dialogue with the user. Simple context sensitive help systems are early examples, while more sophisticated expert system designs typify this era. Control was shared more equally. In this, the third era of the HCI, the constructed system emulates a particular environment, constructed with rules and knowledge about 'reality'. Control is, in part, outside the realm of the human-computer dialogue. Virtual reality systems are discussed.

  10. The Virtual Bookshelf

    NSDL National Science Digital Library

    Island Multimedia has created a virtual library of full-text electronic books, many of which are geared toward a young adult audience. The current selection of 18 titles includes works by American authors Willa Cather, Nathaniel Hawthorne, Edgar Allan Poe, and Mark Twain. The difference between this site and those of other electronic publishers is that here Internauts can register for their own free "virtual bookshelf." With registration comes the ability to highlight favorite passages to return to later, as well as the ability to state preferences for font and background color of the books on your personal bookshelf. Unregistered visitors can click on any "Add to Shelf" box to bring up a registration form. The site has also provided a toll-free phone number for a help line.

  11. Virtual Yeast Cell

    NSDL National Science Digital Library

    Learning about the various parts of a cell can be tricky business, but this virtual yeast cell offered by The University of Nottingham will come in handy for biology students and science instructors. This learning resource was created to help students in the brewing science program learn about yeast cytology, though just about anyone with an interest in cells will learn something from visiting the site. After entering the interactive cell, visitors can click on different parts of the cell (such as the cytoplasm or the nucleus) in order to learn more about the importance of each one. Visitors should remember that they can also download the virtual yeast cell and use it in the classroom or just with a group of friends.

  12. Virtualization Gate Benjamin Petit

    E-print Network

    -camera 3D modeling, phys- ical simulation and tracked HMD for a full-body immersion and presence in virtual. It can also be rendered into a HMD. The user sees his 3D model superposed with his real body occluded by the HMD. Because the displays are hold in front of the e-mail: benjamin.petit@inria.fr e-mail: jean

  13. The Virtual Body

    NSDL National Science Digital Library

    1999-01-01

    The Virtual Body from MEDtropolis.com is an interactive overview of some of the basic structure and function of the human body. The site, available in both English and Spanish, is a mix of information and activities focused on four areas -- the brain, skeleton, heart, and digestive tract. The site's extensive array of diagrams and images, as well as its interactive nature, enhance the site's appeal and educational potential.

  14. Virtual nuclear weapons

    SciTech Connect

    Pilat, J.F.

    1997-08-01

    The term virtual nuclear weapons proliferation and arsenals, as opposed to actual weapons and arsenals, has entered in recent years the American lexicon of nuclear strategy, arms control, and nonproliferation. While the term seems to have an intuitive appeal, largely due to its cyberspace imagery, its current use is still vague and loose. The author believes, however, that if the term is clearly delineated, it might offer a promising approach to conceptualizing certain current problems of proliferation. The first use is in a reference to an old problem that has resurfaced recently: the problem of growing availability of weapon-usable nuclear materials in civilian nuclear programs along with materials made `excess` to defense needs by current arms reduction and dismantlement. It is argued that the availability of these vast materials, either by declared nuclear-weapon states or by technologically advanced nonweapon states, makes it possible for those states to rapidly assemble and deploy nuclear weapons. The second use has quite a different set of connotations. It is derived conceptually from the imagery of computer-generated reality. In this use, one thinks of virtual proliferation and arsenals not in terms of the physical hardware required to make the bomb but rather in terms of the knowledge/experience required to design, assemble, and deploy the arsenal. Virtual weapons are a physics reality and cannot be ignored in a world where knowledge, experience, materials, and other requirements to make nuclear weapons are widespread, and where dramatic army reductions and, in some cases, disarmament are realities. These concepts are useful in defining a continuum of virtual capabilities, ranging from those at the low end that derive from general technology diffusion and the existence of nuclear energy programs to those at the high end that involve conscious decisions to develop or maintain militarily significant nuclear-weapon capabilities.

  15. Virtual Communities of Practice

    Microsoft Academic Search

    Kathryn Hibbert; Sharon Rich

    There is an increased interest in the use of virtual technology and distance courses in professional education. Teacher education\\u000a is no exception, particularly with pressures to maintain professional standards. The problem of course is that the conception\\u000a of what it is to be a professional teacher influences the development of such courses and programs. If teacher is characterized\\u000a as discerner,

  16. Virtual Biology Labs

    NSDL National Science Digital Library

    This Rutgers University Web site contains a set of online biology labs each so detailed and comprehensive, they could nearly replace the real thing. Each virtual lab contains pages and pages of background information and procedures, helpful images and diagrams, online exercises, and more. Seven labs are currently available: Cell Structure, Cell Reproduction, Protists, Plant Evolution, Angiosperm Reproduction, Transport Systems in Plants, and Chromosome Structure and Meiosis.

  17. Distributed virtual instrumentation architecture

    Microsoft Academic Search

    V. Groza; V. Cretu; M. Bogoevici; E. M. Petriu

    2001-01-01

    This paper presents a virtual instrumentation architecture that was conceived by these authors to address specific issues of real-time data acquisition and remote processing in distributed environments for monitoring or C2 (command and control) applications. An object-oriented approach is considered to make full use of the state-of-the-art design and development techniques and technologies. An implementation based on Real-Time Java is

  18. Gallery of Virtual Topography

    NSDL National Science Digital Library

    Stephen Reynolds

    The Gallery of Virtual Topography features virtual depictions of topography, including 3D perspectives and QuickTime Virtual Reality (QTVR) movies, created from Digital Elevation Models (DEM's). The site showcases QTVR object movies where the user can spin a 3D terrain to view it from different perspectives. It also includes static 3D-perspective images (JPEG files) of the 3D terrains for those users with slower Internet connections. Some movies and images depict only the form of the landscape, but in others topographic contours are draped over the landscape to better illustrate how contours portray different types of topography (cliffs versus badlands, for example). Some animations illustrate the significance of contours, by allowing the user to progressively fill the landscape up with water to see the water interact with different topographic features. The site also contains a topographic contour map for each 3D terrain, so that instructors can develop student exercises, such as locating points on a map and constructing topographic profiles. Some QTVR movies contain numbered topographic features just for this purpose.

  19. High efficiency virtual impactor

    DOEpatents

    Loo, Billy W. (Oakland, CA)

    1981-01-01

    Environmental monitoring of atmospheric air is facilitated by a single stage virtual impactor (11) for separating an inlet flow (Q.sub.O) having particulate contaminants into a coarse particle flow (Q.sub.1) and a fine particle flow (Q.sub.2) to enable collection of such particles on different filters (19a, 19b) for separate analysis. An inlet particle acceleration nozzle (28) and coarse particle collection probe member (37) having a virtual impaction opening (41) are aligned along a single axis (13) and spaced apart to define a flow separation region (14) at which the fine particle flow (Q.sub.2) is drawn radially outward into a chamber (21) while the coarse particle flow (Q.sub.1) enters the virtual impaction opening (41). Symmetrical outlet means (47) for the chamber (21) provide flow symmetry at the separation region (14) to assure precise separation of particles about a cutpoint size and to minimize losses by wall impaction and gravitational settling. Impulse defocusing means (42) in the probe member (37) provides uniform coarse particle deposition on the filter (19a) to aid analysis. Particle losses of less than 1% for particles in the 0 to 20 micron range may be realized.

  20. Virtual blood bank.

    PubMed

    Wong, Kit Fai

    2011-01-01

    Virtual blood bank is the computer-controlled, electronically linked information management system that allows online ordering and real-time, remote delivery of blood for transfusion. It connects the site of testing to the point of care at a remote site in a real-time fashion with networked computers thus maintaining the integrity of immunohematology test results. It has taken the advantages of information and communication technologies to ensure the accuracy of patient, specimen and blood component identification and to enhance personnel traceability and system security. The built-in logics and process constraints in the design of the virtual blood bank can guide the selection of appropriate blood and minimize transfusion risk. The quality of blood inventory is ascertained and monitored, and an audit trail for critical procedures in the transfusion process is provided by the paperless system. Thus, the virtual blood bank can help ensure that the right patient receives the right amount of the right blood component at the right time. PMID:21383930

  1. Canada Virtual Science Fair

    NSDL National Science Digital Library

    2008-01-01

    Real science fairs can be great fun, but there's nothing wrong with a virtual science fair, and in the case of the Canada Virtual Science Fair, there's so much that's right. Started in 1999, the Virtual Science Fair is an annual online science and technology contest open to all Canadian students in grades K-12. While non-Canadians aren't eligible to participate, everyone can benefit from the tremendous science education resources on the site. First off, visitors will want to learn about the past winning projects by clicking on the "All Projects" section on the site. Visitors to this section will learn about each project, their team, and so on. Along the right side of the homepage visitors can view the "Special Awards" area. Here they will find information about interesting projects that include "Harvesting Our Nature's Gas Station", "Ice: A Slippery Topic", and "River Pollutants Effect on River Bacteria". Additionally, visitors should be sure to check out their weblog and their online forum.

  2. What is an Atomic Force Microscope? The Lego Scanning Force Microscope (LSPM) is a model of an Atomic Force Microscope (AFM), a very

    E-print Network

    5/28/2008 What is an Atomic Force Microscope? The Lego Scanning Force Microscope (LSPM) is a model of an Atomic Force Microscope (AFM), a very high resolution type of Scanning Probe Microscope at the nanoscale level. The term "microscope" implies looking, while in fact the information is gathered

  3. Microscopic feather fractures in the faulting process

    E-print Network

    Conrad, Robert Eugene

    1974-01-01

    MICROSCOPIC FEATHER I'RACTURES IN THE FAULTING PROCESS A Thesis by ROBERT EUGENE CONRAD II Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1974... Major Subject: Geology MICROSCOPIC FEATHER FRACTURES IN THE FAULTING PROCESS A Thesis by ROBERT EUGENE CONRAD II Approved as to style and content by: ( airman Committee) (Head of Department) mber) (Member) August 197A ABSTRACT Microscopic...

  4. Virtual Humans for Team Training in Virtual Reality

    Microsoft Academic Search

    Jeff Rickel; W. Lewis Johnson

    1999-01-01

    This paper describes the use of virtual humans anddistributed virtual reality to support team training,where students must learn their individual role in theteam as well as how to coordinate their actions withtheir teammates. Students, instructors, and virtualhumans cohabit a 3d, simulated mock-up of their workenvironment, where they can practice together in realisticsituations. The virtual humans can serve asinstructors for individual

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

    PubMed

    Edwards, C S; Christensen, P R

    2013-04-10

    The diversity of investigations of planetary surfaces, especially Mars, using in situ instrumentation over the last decade is unprecedented in the exploration history of our solar system. The style of instrumentation that landed spacecraft can support is dependent on several parameters, including mass, power consumption, instrument complexity, cost, and desired measurement type (e.g., chemistry, mineralogy, petrology, morphology, etc.), all of which must be evaluated when deciding an appropriate spacecraft payload. We present a laboratory technique for a microscopic emission and reflectance spectrometer for the analysis of martian analog materials as a strong candidate for the next generation of in situ instruments designed to definitively assess sample mineralogy and petrology while preserving geologic context. We discuss the instrument capabilities, signal and noise, and overall system performance. We evaluate the ability of this instrument to quantitatively determine sample mineralogy, including bulk mineral abundances. This capability is greatly enhanced. Whereas the number of mineral components observed from existing emission spectrometers is high (often >5 to 10 depending on the number of accessory and alteration phases present), the number of mineral components at any microscopic measurement spot is low (typically <2 to 3). Since this style of instrument is based on a long heritage of thermal infrared emission spectrometers sent to orbit (the thermal emission spectrometer), sent to planetary surfaces [the mini-thermal emission spectrometers (mini-TES)], and evaluated in laboratory environments (e.g., the Arizona State University emission spectrometer laboratory), direct comparisons to existing data are uniquely possible with this style of instrument. The ability to obtain bulk mineralogy and atmospheric data, much in the same manner as the mini-TESs, is of significant additional value and maintains the long history of atmospheric monitoring for Mars. Miniaturization of this instrument has also been demonstrated, as the same microscope objective has been mounted to a flight-spare mini-TES. Further miniaturization of this instrument is straightforward with modern electronics, and the development of this instrument as an arm-mounted device is the end goal. PMID:23670748

  6. Scanning evanescent electro-magnetic microscope

    DOEpatents

    Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Alameda, CA)

    2001-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  7. Foldscope: Origami-based paper microscope

    E-print Network

    Cybulski, James; Prakash, Manu

    2014-01-01

    Here we describe an ultra-low-cost origami-based approach for large-scale manufacturing of microscopes, specifically demonstrating brightfield, darkfield, and fluorescence microscopes. Merging principles of optical design with origami enables high-volume fabrication of microscopes from 2D media. Flexure mechanisms created via folding enable a flat compact design. Structural loops in folded paper provide kinematic constraints as a means for passive self-alignment. This light, rugged instrument can survive harsh field conditions while providing a diversity of imaging capabilities, thus serving wide-ranging applications for cost-effective, portable microscopes in science and education.

  8. Virtual Reality Liver Biopsy Simulator Virtual Reality, Ultrasound-guided Liver Biopsy Simulator

    E-print Network

    Paris-Sud XI, Université de

    Virtual Reality Liver Biopsy Simulator Virtual Reality, Ultrasound-guided Liver Biopsy Simulator: Development and Performance Discrimination1 Running head: Virtual Reality Liver Biopsy Simulator Word count (exc. Figures / tables): 4210 Key Words: Interventional Radiology, Simulation, Virtual Reality

  9. Evolution of the Taupo Volcanic Center, New Zealand: petrological and thermal constraints from the Omega dacite

    NASA Astrophysics Data System (ADS)

    Gelman, Sarah E.; Deering, Chad D.; Gutierrez, Francisco J.; Bachmann, Olivier

    2013-11-01

    The 20 ka ~0.1 km3 Omega dacite, which erupted shortly after the 26.5 ka Oruanui super-eruption, compositionally stands out among Taupo Volcanic Zone (TVZ) magmas, which are overwhelmingly characterized by rhyolites (>90 % by volume). The previously reported presence of inherited zircons in this zircon-undersaturated magma has provided unequivocal evidence for the involvement of upper-crustal material in a 1-10 year timescale prior to the Omega eruption. However, whether this crustal involvement is characterized by wholesale, melting of preexisting crust or subordinate bulk assimilation into an already differentiated magma body remains unclear. To disentangle these processes, we describe the mineral chemistry of the major phases present in the Omega dacite and determine intensive parameters describing magma chamber conditions. Dominantly unimodal populations of plagioclase (An50-60), orthopyroxene (Mg# from 58 to 68), and clinopyroxene (Mg# from 65 to 73), along with coexisting equilibrium pairs of Fe-Ti oxides, constrain pre-eruptive temperatures to 850-950 °C, a pressure between ~3 and 7 kbars, and an oxygen fugacity of ~NNO. MELTS thermodynamic modeling suggests that this phase assemblage is in equilibrium with the bulk rock and glass compositions of the Omega dacite at these estimated P- T- fO2 pre-eruptive conditions. Combining these petrological observations with insights into conductive thermal models of magma-crust interactions, we argue that the Omega dacite more likely formed in the mid-to-lower crust via protracted processing through fractional crystallization coupled with some assimilation (AFC). Incorporation of crustal material is likely to have occurred at various stages, with the inherited zircons (and potentially parts of glomerocrysts) representing late and subordinate upper-crustal assimilants. This petrogenetic model is consistent with the presence of a differentiating crustal column, consisting of a polybaric fractional crystallization and assimilation history. On the basis of petrological, thermal, and geophysical considerations, upper-crustal reservoirs, which feed large-scale rhyolitic volcanism in the TVZ, most likely take the form of large, long-lived crystal mush zones. Following large eruptions, such as the Oruanui event, this mush is expected to crystallize significantly (up to 70-80 vol% crystals) due to syn-eruptive decompression. Hence, the Omega dacite, immediately post-dating the Oruanui event, potentially represents incoming deeper recharge of less-evolved magma that was able to penetrate the nearly solidified upper-crustal mush. Over the past 20,000 years, similar intermediate recharge magmas have incrementally reheated, reconstructed, and reactivated the upper-crustal mush zone, allowing a gradual return to rhyolitic volcanism at the Taupo Volcanic Center.

  10. Morphological study of Insoluble Organic Matter from carbonaceous chondrites: Correlation with petrologic grade

    NASA Astrophysics Data System (ADS)

    Changela, Hitesh G.

    2015-06-01

    The major form of organic material delivered to Earth from an extraterrestrial origin is Insoluble Organic Matter (IOM). A morphological study of IOM in the CR (Renazzo-type) and CM (Mighei-type) carbonaceous chondrites was performed in order to constrain its origins and processing history. IOM residues from the following CR chondrites: GRO 95577 (CR1), Al Rais (CR1/2), EET 92042 (CR2), QUE 99177 (CR3) and the CM chondrites: MET 01070 (CM2.2), Cold Bokkeveld (CM2.3), Murchison (CM2.4) and QUE 97990 (CM2.5) were studied using Annular Dark Field STEM imaging. Characteristic features of the IOM, organic nanoglobules, were manually identified and measured for their abundances and size distributions. The IOM residues were also compared holistically for their degree of average 'roughness' or 'coarsening' using fractal image analysis. Manually identified nanoglobules have abundances making up less than 10% of the total IOM, which is consistent with previous studies. Their measured abundances do not correlate with petrologic grade. Thus parent body processing did not systematically deplete their abundances. The IOM is however on average 'smoother' or 'coarser' in the more altered chondrites, demonstrated by a lower fractal dimension using fractal box counting (DB). The DB values for the IOM in the CR chondrites are distinctive: QUE 99177 has the largest DB value (average = 1.54 ± 0.004) and GRO 99577 has the lowest (average = 1.45 ± 0.011). Al Rais and EET 92042 have IOM with average DB values within this range (average, 1.46 ± 0.009 and 1.50 ± 0.006). The CMs record a similar but less distinctive trend in DB, with QUE 97990 having the largest value (1.52 ± 0.004), MET 01070 the lowest (1.45 ± 0.019), and Cold Bokkeveld (1.50 ± 0.011) and Murchison (1.49 ± 0.017) equivalent to one another within error. The identified nanoglobules in the IOM of the CM chondrites are on average larger than those in the CR chondrites. The 'coarsening' or 'smoother' texture of the IOM (lower DB) in the more altered chondrites coupled with a tentative increase in the size of large features (identified nanoglobules) demonstrates that the aqueous processes leading to the lower petrologic types also formed the overall IOM morphology. In addition, observations of fluid-like textures more frequently found in the more altered carbonaceous chondrite residues suggests that organic and aqueous fluids determined at least some of these morphologies. The polymerization of organic solutions is consistent with these morphologies. Their formation conditions are more favorable under the containment of carbonaceous chondrite parent bodies.

  11. Petrological and geochemical characterization of Proterozoic ophiolitic mélange, Nellore-Khammam schist belt, SE India

    NASA Astrophysics Data System (ADS)

    Dharma Rao, C. V.; Reddy, U. V. B.

    2009-10-01

    The ophiolitic mélange occurs close to a major fault within the metavolcanics of Kanigiri area in the western margin of the Khammam-Nellore schist belt, Andhra Pradesh, India. The unique feature of Kanigiri mélange is the occurrence of ophiolitic bodies of various sizes, most of which display petrological and geochemical characteristics typical of supra-subduction zone oceanic crust. The ophiolitic mélange is composed mainly of blocks of variably deformed and metamorphosed pillow basalts, serpentinized ultramafic rocks, meta-gabbros, cherts and pelagic sediments in a pervasive scaly argillite matrix. The mélange has a tectonic contact with a granite intrusion and numerous thrust faults cut across the mélange exposures. Primary magmatic features such as drainage cavities in pillow basalts, magmatic layering in gabbros, and clinopyroxene cumulates in ultramafic rocks are well preserved in low-strain domains. Mafic components enclosed in the mélange are characterized by low pressure secondary mineral assemblages retrograded from amphibolite down to greenschist facies as commonly observed in subducted and exhumed orogens. All amphiboles in the studied fragments are calcic and cluster in the range from winchite, actinolite to hornblende. Amphibole compositions are characterized by Al 2O 3 (2.4-13.8%), FeO (5-13%), K 2O (0.04-0.7%) and X Mg (0.67-0.77). The metabasalt and wherlite samples exhibit light rare earth element (LREE) - enriched patterns and negative high field strength element (HFSE: Zr and Ti) consistent with a suprasubduction zone geodynamic setting. A notable feature of both metabasalt and wherlite samples is their pronounced negative Ce anomaly and a positive Eu anomaly as observed in a number of modern island arc suites. As the petrological features and the geochemical characteristics of the remnant fragments we analyzed in this study are reminiscent of their Phanerozoic ophiolite counterparts, we suggest that these rocks were derived from a Proterozoic oceanic plate belonging to a suprasubduction ophiolite assemblage. Subduction zone geochemical signatures and ophiolite-like crustal lithologies in the study region are consistent with the accretion of juvenile oceanic fragments to the pre-existing continental blocks through a forearc-continent collision.

  12. Petrology of 1977 to 1998 eruptions of Piton de la Fournaise, La Réunion Island

    NASA Astrophysics Data System (ADS)

    Boivin, Pierre; Bachèlery, Patrick

    2009-07-01

    Geochemical and petrological variations in 35 historical eruptions from the April 1977 eruption to the March-September 1998 eruption at Piton de la Fournaise have been analyzed for their major elements abundances, mineralogical compositions and oxygen isotopes. During these 21 years, samplings were repeated several times during eruptions as well as temperature measurements. Since the end of 1977 to 1998, all erupted lavas, except 1998-Hudson basalt, belong to the group of the "steady state basalts". However, evidences for small degrees of differentiation can be observed. During a single eruption, the earliest lava emitted contains less phenocrysts and has almost always a lower MgO* (= MgO/[MgO + FeOt]) than the lavas emitted later, suggesting that it is more differentiated. From one eruption to the next, between 1977 and 1998, bulk compositions are more and more differentiated towards the first lava of 1998. A process of low-pressure fractional crystallisation, involving small proportions of olivine, clinopyroxene and plagioclase, allows to explain this evolution. A major result of our study is to show that this evolution does not correspond to a unique fractionation trend. Over the considered period, different types of magmas have been distinguished. The first magma type, erupted from October 1977 to November 1987, was richer in potassium (0.82 wt.% in average) than the second one, and apparently derived from the liquid of the 1977 oceanite. The second magma type, erupted from February 1988 to September 1998, was poorer in K 2O (0.69 wt.% in average). In March 1998, a third magma type (Hudson basalt) erupted simultaneously with the second one. Hudson basalt has undergone a wehrlitic fractionation and is supposed to come from a deeper magma reservoir than other erupted magmas for this period. From 1977 to 1998, the ? 18O of lavas progressively decreases with time, together with the increasing chemical differentiation of the magmas by low-pressure fractional crystallisation. This variation agrees with the hypothesis of magma contamination at shallow level in the altered volcanic edifice (Vlastélic, I., Deniel, C., Bosq, C., Télouk, P., Boivin, P., Bachèlery, P., Famin, V., Staudacher, T., 2009-this issue. Pb isotope geochemistry of Piton de la Fournaise historical lavas. Journal of Volcanology and Geothermal Research, 184, 63-78 (this issue)). Overall, petrological variations are in good agreement with a model of a shallow reservoir discontinuously supplied between 1977 and 1998. The speed of the variations, the coexistence of different liquids, the chemical evolution of the lavas during the same eruption, lead us to favour a model of chemically stratified reservoir, constituted by a complex of dykes, sills and laccoliths close to the surface and located above larger magma bodies.

  13. The Morne Aux Diables volcano, Dominica, Lesser Antilles: A stratigraphic and petrologic study.

    NASA Astrophysics Data System (ADS)

    Daly, G. L.; Smith, A. L.; Rheubottom, A. N.; Fryxell, J. E.

    2008-12-01

    Morne Aux Diables is a topographically distinct stratovolcano located at the northernmost end of the island of Dominica, Lesser Antilles. In 2007, observations were conducted, and over 3,000 digital photographs were taken, of the well-exposed sea cliffs around Dominica. These observations, together with photogeological analysis of approximately 500 of these digital photographs of sea cliffs around the northern part of Dominica, have significantly improved our understanding of the geology of Morne aux Diables volcano, which previously had been based on scattered land exposures. The photographs were used to identify genetic packages of strata related to volcanogenic events and trace them around large sectors of the volcano's flanks. Based on these new studies, together with previous data, Morne aux Diables appears to have undergone two periods of activity, an older period dated between 2.1-1.5 Ma and a younger period dated at around 50,000 years B.P. Deposits associated with the older cone-forming activity are primarily composed of block and ash flows and surges associated with Pelean-style activity. These can be subdivided into a number of sequences based on the presence of paleosols. Domes associated with these eruptions are found both in the central vent area as well as around the flanks of the volcano. The upper deposits in the sea cliffs on the eastern, northern and western flanks are a thick sequence of surges that have been provisionally correlated with a well-exposed sequence of semi-vesicular block and ash flows and surge deposits at Morne a Louis on the west coast. The presence of these surge deposits at the top of the sea cliffs suggests that the older period of activity ended with open-crater Asama-style eruptions. Following an extensive quiescent period, renewed Pelean-style activity produced valley-fill block and ash flow and surge deposits, exposed on both the eastern and western sides of the volcano, together with associated domes (both central and parasitic). Petrographic studies show that Morne Aux Diables volcano is composed of andesites and dacites with a mineral assemblage of plagioclase+augite±hypersthene with minor hornblende and quartz. Geochemically both the older and younger volcanic rocks show trends, especially in terms of alkalis, that are slightly lower and cross- cut from those shown by the other centers on Dominica. These stratigraphic and petrologic studies will help further elucidate the volcanic history of Morne aux Diables and allow a petrologic-stratigraphic model of its formation.

  14. Radio-induced alteration in cordierite - Implications for petrology, gemmology and materials science

    NASA Astrophysics Data System (ADS)

    Krickl, R.; Nasdala, L.; Grambole, D.; Kaindl, R.

    2009-04-01

    Cordierite is a common metamorphic and magmatic mineral, which is used as petrologic tool for reconstructing the history of its host rock. Further applications include cordierite gemstones and the use of synthetic analogs in ceramics. Cordierite is stable over a wide temperature and pressure range and relatively resistant to chemical alteration; however, its properties can be significantly changed upon the impact of external irradiation. In the course of a comprehensive study, natural radiohaloes in cordierite (a widespread feature caused by the impact of alpha-particles originating from radioactive inclusions) as well as artificial analogs produced by implantation of 8.8 MeV He2+ ions were investigated using modern micro-techniques. Additional irradiation experiments were performed using O6+ ions, electrons and gamma-rays. Ion irradiation causes yellow colouration that is strongly pleochroic, and fades at higher doses. The possibility of radiation-treatment for enhancing the quality of gem-cordierite is discussed. While samples remain crystalline up to doses of 1016 He2+/cm2, the same material is fully amorphised when irradiated with the same dose of 30 MeV O6+ ions. These different observations may help to estimate the performance assessment of cordierite-ceramics in radiated environments. A very important result concerning the petrological use of cordierite is the radio-induced transformation of channel constituents: Inside the irradiated areas the vibrational bands of CO2 decrease in intensity, whereas two new bands appear at 2135 cm-1 (both IR- and Raman-active; cf. Nasdala et al., 2006) and 1550 cm-1 (only Raman-activ). They are assigned to stretching vibrations of carbon monoxide and molecular oxygen, respectively, thus indicating a radio-chemical transformation 2CO2 ? 2CO + O2 in alpha-irradiated cordierite. This study yields the first spectroscopic evidence for the irradiation-induced formation of molecular oxygen in cordierite. Polarised vibrational spectra of oriented samples give evidence that not only CO2 but also CO and O2 are preferentially oriented parallel [100], most probably being located at the Ch

  15. Petrology and Geochemistry of the Northeast Seamounts of the Galapagos Platform

    NASA Astrophysics Data System (ADS)

    Sinton, C. W.; Harpp, K. S.; Christie, D. M.

    2010-12-01

    One of the best locations to study hotspot-ridge interactions is the Northern Galápagos Province (NGP), the region that lies between the Galapagos Spreading Center (GSC) and the central portion of the Galapagos Archipelago. The Galapagos hotspot is currently located off-axis from the GSC but still has a profound influence on the ridge in terms of axial lava composition and ridge bathymetry. The NGP is characterized by an array of volcanic lineaments that are composed of seamounts and five small islands. The eastern edge of the NGP is defined by a group of at least five seamounts (the Northeast Seamounts), three of which were mapped and dredged in 1990 during Leg 2 of the PLUME expedition of the R/V Thomas Washington. We report petrological and geochemical data from the basalts recovered at six dredge sites. All basalts are tholeiitic with a general MORB-like composition, but with considerable variation within some individual dredge hauls and between seamounts. Previously published isotopic data are limited but 3He/4He ratios (Graham et al. 1993) and Sr-Nd-Pb isotopic data (Harpp and White 2000) are consistent with a depleted mantle source for all three seamounts. Based on geochemistry and petrological observations, the basalts can be divided into at least thirteen distinct groups. The bulk of the analyzed glass samples have compositions more than MORB with MgO content of 8-10% wt., although two of the groups are in the 6-7% range. In addition, the primitive lavas have high CaO and Al2O3 . The mineralogy ranges from aphyric for the more evolved lavas to olivine + plagioclase-phyric or plagioclase ultraphyric for the more primitive basalts. The plagioclase appear to be very calcic (up to An91) xenocrysts that are often hosting aluminous spinel (Al2O3 46-48% wt.) and primitive melt inclusions (Sinton et al., 1993). Initial trace element data show light rare earth (LREE)-depleted signatures, although several samples are slightly enriched in the LREE. Taken together, the data indicate that the seamounts were produced by variable extents of melting of a depleted mantle source. The mineralogy and geochemistry of the Northeastern Seamounts is similar to off-axis volcanoes, such as the Lamont Seamounts. We suggest that the Northeast Seamounts formed by passive rifting of young oceanic crust in which partial melts in the underlying mantle migrate in response to regional stresses. The primitive nature of the melts indicates the lack of a large magma chamber typical of those underlying mid-ocean ridges.

  16. Surgery applications of virtual reality

    NASA Technical Reports Server (NTRS)

    Rosen, Joseph

    1994-01-01

    Virtual reality is a computer-generated technology which allows information to be displayed in a simulated, bus lifelike, environment. In this simulated 'world', users can move and interact as if they were actually a part of that world. This new technology will be useful in many different fields, including the field of surgery. Virtual reality systems can be used to teach surgical anatomy, diagnose surgical problems, plan operations, simulate and perform surgical procedures (telesurgery), and predict the outcomes of surgery. The authors of this paper describe the basic components of a virtual reality surgical system. These components include: the virtual world, the virtual tools, the anatomical model, the software platform, the host computer, the interface, and the head-coupled display. In the chapter they also review the progress towards using virtual reality for surgical training, planning, telesurgery, and predicting outcomes. Finally, the authors present a training system being developed for the practice of new procedures in abdominal surgery.

  17. Research and Applications of Virtual Medicine

    Microsoft Academic Search

    Pheng Ann Heng

    2005-01-01

    In this paper, we would like to share our experience in developing various virtual medicine applications, including virtual arthroscopy, virtual acupuncture and virtual anatomy. We have deployed the latest graphics processor to develop these virtual reality based learning and training systems. Having utilized various visible human datasets, the visual quality of the applications has been greatly improved

  18. VIRTUAL KNOT GROUPS Daniel S. Silver

    E-print Network

    Williams, Susan

    VIRTUAL KNOT GROUPS Daniel S. Silver Susan G. Williams ABSTRACT. Virtual knot groups, generalizing the usual notion of Fox n-coloring, is introduced for virtual oriented links. 1. INTRODUCTION. We the concept of a virtual knot [Ka1]. He did this by allowing a third type of crossing, a so-called virtual

  19. The virtual environment display system

    NASA Technical Reports Server (NTRS)

    Mcgreevy, Michael W.

    1991-01-01

    Virtual environment technology is a display and control technology that can surround a person in an interactive computer generated or computer mediated virtual environment. It has evolved at NASA-Ames since 1984 to serve NASA's missions and goals. The exciting potential of this technology, sometimes called Virtual Reality, Artificial Reality, or Cyberspace, has been recognized recently by the popular media, industry, academia, and government organizations. Much research and development will be necessary to bring it to fruition.

  20. A virtual instrumentation support system

    Microsoft Academic Search

    L. F. F. Brito Palma; Adelino R. F. da Silva

    1998-01-01

    A virtual instrumentation support system that permits one to run several concurrent virtual instruments has been developed. In this paper, we present a multi-tasking graphical environment (named AGMT) and two main virtual instrumentation applications-a digital oscilloscope and a digital image processor. The AGMT was designed to work in real-time and interact with sensors and actuators via data acquisition boards, and

  1. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of gametes or embryos. Variations of microscopes and accessories used for these purposes would include phase contrast microscopes, dissecting...

  2. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of gametes or embryos. Variations of microscopes and accessories used for these purposes would include phase contrast microscopes, dissecting...

  3. 21 CFR 884.6190 - Assisted reproductive microscopes and microscope accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...which are classified under assisted reproduction accessories) are optical instruments used to enlarge images of gametes or embryos. Variations of microscopes and accessories used for these purposes would include phase contrast microscopes, dissecting...

  4. Microscopic linear liquid streams in vacuum: Injection of solvated biological samples into X-ray free electron lasers

    SciTech Connect

    Doak, R. B.; DePonte, D. P.; Nelson, G.; Camacho-Alanis, F.; Ros, A.; Spence, J. C. H.; Weierstall, U. [Arizona State University, Tempe, AZ 85287-1504 (United States); Centre for Free-Electron Laser Science, DESY, D-22607 Hamburg (Germany); Arizona State University, Tempe, AZ 85287-1504 (United States)

    2012-11-27

    Microscopic linear liquid free-streams offer a means of gently delivering biological samples into a probe beam in vacuum while maintaining the sample species in a fully solvated state. By employing gas dynamic forces to form the microscopic liquid stream (as opposed to a conventional solid-walled convergent nozzle), liquid free-streams down to 300 nm diameter have been generated. Such 'Gas Dynamic Virtual Nozzles' (GDVN) are ideally suited to injecting complex biological species into an X-ray Free Electron Laser (XFEL) to determine the structure of the biological species via Serial Femtosecond Crystallography (SFX). GDVN injector technology developed for this purpose is described.

  5. Scanning Microscopes Using X Rays and Microchannels

    NASA Technical Reports Server (NTRS)

    Wang, Yu

    2003-01-01

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

  6. Virtual Microscopy: A Useful Tool for Meeting Evolving Challenges in the Veterinary Medical Curriculum

    NASA Astrophysics Data System (ADS)

    Kogan, Lori R.; Dowers, Kristy L.; Cerda, Jacey R.; Schoenfeld-Tacher, Regina M.; Stewart, Sherry M.

    2014-12-01

    Veterinary schools, similar to many professional health programs, face a myriad of evolving challenges in delivering their professional curricula including expansion of class size, costs to maintain expensive laboratories, and increased demands on veterinary educators to use curricular time efficiently and creatively. Additionally, exponential expansion of the knowledge base through ongoing biomedical research, educational goals to increase student engagement and clinical reasoning earlier in the curriculum, and students' desire to access course materials and enhance their educational experience through the use of technology all support the need to reassess traditional microscope laboratories within Professional Veterinary Medical (PVM) educational programs. While there is clear justification for teaching veterinary students how to use a microscope for clinical evaluation of cytological preparations (i.e., complete blood count, urinalysis, fecal analysis, fine needle aspirates, etc.), virtual microscopy may be a viable alternative to using light microscopy for teaching and learning fundamental histological concepts. This article discusses results of a survey given to assess Professional Veterinary Medical students' perceptions of using virtual microscope for learning basic histology/microscopic anatomy and implications of these results for using virtual microscopy as a pedagogical tool in teaching first-year Professional Veterinary Medical students' basic histology.

  7. Diagnosis of major cancer resection specimens with virtual slides: impact of a novel digital pathology workstation.

    PubMed

    Randell, Rebecca; Ruddle, Roy A; Thomas, Rhys G; Mello-Thoms, Claudia; Treanor, Darren

    2014-10-01

    Digital pathology promises a number of benefits in efficiency in surgical pathology, yet the longer time required to review a virtual slide than a glass slide currently represents a significant barrier to the routine use of digital pathology. We aimed to create a novel workstation that enables pathologists to view a case as quickly as on the conventional microscope. The Leeds Virtual Microscope (LVM) was evaluated using a mixed factorial experimental design. Twelve consultant pathologists took part, each viewing one long cancer case (12-25 slides) on the LVM and one on a conventional microscope. Total time taken and diagnostic confidence were similar for the microscope and LVM, as was the mean slide viewing time. On the LVM, participants spent a significantly greater proportion of the total task time viewing slides and revisited slides more often. The unique design of the LVM, enabling real-time rendering of virtual slides while providing users with a quick and intuitive way to navigate within and between slides, makes use of digital pathology in routine practice a realistic possibility. With further practice with the system, diagnostic efficiency on the LVM is likely to increase yet more. PMID:25128229

  8. 3D reconstruction based on wavelet pyramid image fusion algorithm for digital microscope

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Liu, Peng; Liu, Yuling; Yu, Feihong

    2009-11-01

    Optical microscopy is an important technique in petrological and biological. However, because of the limited focus depth of a traditional optical microscope, 3D objects can't be observed with all its information in one scene. The commonly used method to solve this problem is to use a digital microscope to collect a sequence of multi-focus images with a constant change of the focal length and then get the final sharp image by fusing the images. Wavelet pyramid algorithm is one of the commonly used fusion algorithms and has a good performance. In this paper, a novel 3D reconstruction algorithm is presented based on the wavelet pyramid image fusion algorithm. First, a sequence of multi-focus images is collected with a digital microscope and then the images are fused with the wavelet pyramid fusion algorithm. After that, the deviation between the fused image and each of the original multi-focus images are calculated pixel by pixel. For convenience, the absolute value of the deviation is calculated. The smaller the deviation, the closer the corresponding pixel to the focal plane and vice versa. Thus a 3D deviation matrix is obtained. For each pixel position (x, y), the z index of the smallest deviation value in the third direction of the deviation matrix is considered the pixel's height index. A complete height index map is obtained by selecting the indices of these smallest deviation values. In order to eliminate the noise effect, a median filter is applied to the height index map. The height index map times the height factor (the unit step length along the optical axis when collecting the multi-focus images) is the object's actual height map. Finally, the surface of the 3D object is reconstructed with the object's height map. In order to test the reconstruction algorithm, a dedicated high resolution Complementary Metal Oxide Semiconductor (CMOS) digital microscope is designed and fabricated to collect the multi-focus images. Experimental results show that the proposed algorithm produces a nice looking surface of a 3D object.

  9. The Impacts of Animated-Virtual Actors' Visual Complexity and Simulator Sickness in Virtual Reality Applications

    E-print Network

    Cheng, Ken

    The Impacts of Animated-Virtual Actors' Visual Complexity and Simulator Sickness in Virtual Reality Virtual Actors' (AVAs) visual complexity on Simulator Sickness (SS) in Virtual Reality (VR) applications. Keywords-virtual actors; virtual reality; visual complexity; simulation sickness; visualisation I

  10. VIRTUAL TRAINING CENTRE FOR SHOE DESIGN: A SAMPLE VIRTUAL TRAINING ENVIRONMENT

    E-print Network

    Aristomenis, Antoniadis

    VIRTUAL TRAINING CENTRE FOR SHOE DESIGN: A SAMPLE VIRTUAL TRAINING ENVIRONMENT Aura Mihai1 , Mehmet@tex.tuiasi.ro Abstract It is a fact that virtual training has become a key issue in training. There are numerous virtual for creating a virtual learning environment. When we mention "virtual training", in fact, our stress is on two

  11. Navigating Virtual Agents in Online Virtual Worlds Russell Gayle Dinesh Manocha

    E-print Network

    North Carolina at Chapel Hill, University of

    Navigating Virtual Agents in Online Virtual Worlds Russell Gayle Dinesh Manocha Department://gamma.cs.unc.edu/SecondLife a b c Real agent Virtual agents Virtual tour guide Virtual tour group Figure 1: College campus: (a) Many areas in online virtual worlds, such as this college campus in Second Life R , are sparsely

  12. Virtual Wealth Realization in Virtual and Real Worlds Jingzhi Guo, Angelina Chow and Zhiguo Gong

    E-print Network

    Guo, Jingzhi

    Virtual Wealth Realization in Virtual and Real Worlds Jingzhi Guo, Angelina Chow and Zhiguo Gong This paper has investigated the issue of virtual wealth and its realization in both real and virtual worlds, and argued that the realization of virtual wealth is necessary and possible. On the formation of virtual

  13. Industrial applications' simulation technologies in virtual environments Part 1: Virtual Prototyping

    E-print Network

    Aristomenis, Antoniadis

    Prototypes for products. In the Virtual Prototypes that are developed with the use of Virtual Reality: Virtual Prototyping, Virtual Reality, Virtual Environment, Industrial Simulation #12;2 1. INTRODUCTION Reality head mounted display, data glove, etc.) in the virtual environment is essential mainly

  14. Scanning electron microscopic studies of cilia

    Microsoft Academic Search

    V. C. Barber; A. Boyde

    1967-01-01

    A simple method for the preparation of ciliated epithelia for study with the scanning electron microscope is described. Ciliary groups are well preserved and it is possible to discern individual cilia and work out their numbers and orientation. Following scanning electron microscopical study some of the material was prepared for transmission electron microscopy and the ultrastructure of the tissue was

  15. Electron Microscope Center Opens at Berkeley.

    ERIC Educational Resources Information Center

    Robinson, Arthur L.

    1981-01-01

    A 1.5-MeV High Voltage Electron Microscope has been installed at the Lawrence Berkeley Laboratory which will help materials scientists and biologists study samples in more true-to-life situations. A 1-MeV Atomic Resolution Microscope will be installed at the same location in two years which will allow scientists to distinguish atoms. (DS)

  16. A microscopic simulator for urban traffic systems

    Microsoft Academic Search

    Lin Yong; Cai Yuan Li

    2002-01-01

    Based on microscopic traffic models, the object-oriented method and visualization technology are applied to the microscopic simulation of urban traffic systems, and a concise and flexible traffic simulator is developed. For an urban traffic network with 3 by 3 intersections, simulation results show that the vehicle behaviors in the traffic network accord with human traffic experience, and the movement curves

  17. Community Engagement Under the Microscope Community Engagement

    E-print Network

    Rambaut, Andrew

    Community Engagement ­ Under the Microscope Community Engagement ­ Under the Microscope 12­15 June 2011 #12;#12;Contents Executive summary 4 Introduction 6 What is community engagement with health research? 7 Politics and power 11 Why do we engage with communities? 13 Who is the community? 15 Community

  18. Petrologic-petrophysical-engineering relationships, selected wells near the Arctic National Wildlife Refuge, Alaska

    SciTech Connect

    Mowatt, T.C.; Gibson, C.; Seidlitz, A.; Bascle, R.; Dygas, J. (U.S. Bureau of Land Management, Anchorage, AK (United States))

    1991-03-01

    In the context of the reservoir management and resource assessment programs of the U.S. Bureau of Land Management in Alaska, selected stratigraphic horizons were studied in a number of wells adjacent to the Arctic National Wildlife Refuge (ANWR), northeast Alaska. Petrographic analyses were integrated with petrophysical and engineering data, in order to provide a substantive knowledge base from which to infer reservoir potentials elsewhere in the region, using geological and geophysical methods. Of particular interest in the latter regard is the ANWR area. Horizons of concern with regard to reservoir characteristics include Franklinian through Brookian strata. Of particular interest are clastic Ellesmerian 'Break-up/Rift Sequence' sediments such as the Lower Cretaceous Thomson sand, and deeper-water marine clastics, as exemplified by the Brookian Colville Group 'turbidites.' Also of concern are pre-Ellesmerian 'basement' rocks, some of which are hosts to hydrocarbon accumulations in the Point Thomson field. Petrologic-mineralogic characteristics have been keyed to various wireline log responses and related to available engineering data, as feasible, for the wells considered. Synthesis of this information in terms of the regional geological framework, tied in with geophysical data, will facilitate more refined, effective resource assessment and management.

  19. Mineralogical, petrological and geochemical aspects of alkaline and alkaline-carbonatite associations from Brazil

    NASA Astrophysics Data System (ADS)

    Morbidelli, L.; Gomes, C. B.; Beccaluva, L.; Brotzu, P.; Conte, A. M.; Ruberti, E.; Traversa, G.

    1995-12-01

    A general description of Mesozoic and Tertiary (Fortaleza) Brazilian alkaline and alkaline-carbonatite districts is presented with reference to mineralogy, petrology, geochemistry and geochronology. It mainly refers to scientific results obtained during the last decade by an Italo-Brazilian research team. Alkaline occurrences are distributed across Brazilian territory from the southern (Piratini, Rio Grande do Sul State) to the northeastern (Fortaleza, Ceará State) regions and are mainly concentrated along the borders of the Paraná Basin generally coinciding with important tectonic lineaments. The most noteworthy characteristics of these alkaline and alkaline-carbonatite suites are: (i) prevalence of intrusive forms; (ii) abundance of cumulate assemblages (minor dunites, frequent clinopyroxenites and members of the ijolite series) and (iii) abundance of evolved rock-types. Many data demonstrate that crystal fractionation was the main process responsible for magma evolution of all Brazilian alkaline rocks. A hypothesis is proposed for the genesis of carbonatite liquids by immiscibility processes. The incidence of REE and trace elements for different major groups of lithotypes, belonging both to carbonatite-bearing and carbonatite-free districts, are documented. Sr and preliminary Nd isotopic data are indicative of a mantle origin for the least evolved magmas of all the studied occurrences. Mantle source material and melting models for the generation of the Brazilian alkaline magma types are also discussed.

  20. Petrology and geochemistry of mafic granulite xenoliths from the Lahtojoki kimberlite pipe, eastern Finland

    NASA Astrophysics Data System (ADS)

    Hölttä, P.; Huhma, H.; Mänttäri, I.; Peltonen, P.; Juhanoja, J.

    2000-03-01

    The Lahtojoki kimberlite pipe in Kaavi, eastern Finland contains lower crustal mafic granulite xenoliths with a mineral assemblage cpx-amph-pl±grt±opx±bt. The TWEEQU thermobarometry indicates crystallization at ca. 800-900°C and 0.75-1.25 GPa, which corresponds with crustal depths of ca. 22-38 km. Reaction textures and results of thermobarometry in some xenoliths indicate post-peak decompression with cooling. Chemical composition of the xenoliths suggest that their protoliths crystallized from basaltic melts, with some K-enrichment. Their REE patterns are slightly LREE-enriched, some xenoliths having small negative Eu anomalies. The U-Pb ion probe dating of zircons from two samples yielded variable ages for zircons even in the same xenolith, between ca. 2.6 and 1.7 Ga. These ages correspond with main late Archaean and Palaeoproterozoic orogenic events in the Fennoscandian shield. The Sm-Nd garnet-clinopyroxene isochron age from one dated sample is 1.6 Ga, which represents either a cooling or reheating of the lower crust by rapakivi magmatism. Because the petrology, geochemistry and ages of xenoliths do not correlate well with the nearest exposed Archaean mafic granulites, it is evident that the present lower crust, underlying the Archaean rocks, has a considerable Palaeoproterozoic component.