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Sample records for environmental scanning orientado

  1. Environmental Scanning Report, 1992.

    ERIC Educational Resources Information Center

    Yao, Min

    In response to the change in the provincial economy from natural-resource-based industries to service-oriented industries, Vancouver Community College (VCC) in British Columbia (BC) conducted an environmental scan of the social and economic trends in the college's service region that will most likely affect prospective students' educational and…

  2. Environmental Scanning, Vancouver Community College.

    ERIC Educational Resources Information Center

    Yao, Min

    This 1994 environmental scanning report from Vancouver Community College (VCC) reviews the expected effects of the separation of VCC into a new Vancouver Community College and Langara College (LC). The report examines the projected service area student-intake capacity; student characteristics; population growth trends; other postsecondary…

  3. South Carolina Course Alignment Project: Environmental Scan

    ERIC Educational Resources Information Center

    Educational Policy Improvement Center (NJ1), 2007

    2007-01-01

    An "environmental scan" is designed to identify key issues of policy and practice in an area of interest so that action can be taken. By definition, an environmental scan focuses upon areas of concern. However, the results of an environmental scan are not designed to be either an indictment or endorsement of the current way of doing…

  4. Scans Solo: A One-Person Environmental Scanning Process.

    ERIC Educational Resources Information Center

    Clagett, Craig A.

    An effective environmental scan will improve the quality of community college planning and decision making by alerting institutional leaders to the challenges and opportunities in the environment. Scanning can be done in three ways: (1) establishing a scanning committee to gather and synthesize information to guide planning; (2) sponsoring a…

  5. Service Area Market Analysis: Environmental Scanning.

    ERIC Educational Resources Information Center

    Front Range Community Coll., Westminster, CO.

    This environmental scanning report presents, in brief, various key indicators: political climate, population demographics, secondary education, postsecondary education, welfare, unemployment, industry, labor, and general conclusions. General conclusions made in this report are as follows: higher education is expected to receive a slight increase…

  6. Environmental Scanning: Assessing Local Business Training Needs.

    ERIC Educational Resources Information Center

    Clagett, Craig A.; Huntington, Robin B.

    Environmental scanning (ES) is a formal process of assessing trends and forecasting events which can influence an institution so that the potential challenges and opportunities can be effectively anticipated during strategic planning activities. The goal of ES is the implementation of proactive, anticipatory policies that will be robust under a…

  7. 2006 Environmental Scan. ACAATO Archive Document

    ERIC Educational Resources Information Center

    Colleges Ontario, 2006

    2006-01-01

    The Association of Colleges of Applied Arts and Technology of Ontario (ACAATO) is pleased to present this report. The 2006 Environmental Scan provides an aggregate synopsis of the key trends which will impact on Ontario's Colleges of Applied Arts and Technology in the future and will assist colleges in their advocacy and strategic planning…

  8. 2005 Environmental Scan. ACAATO Archive Document

    ERIC Educational Resources Information Center

    Colleges Ontario, 2005

    2005-01-01

    The Association of Colleges of Applied Arts and Technology of Ontario (ACAATO) is pleased to present this report. The 2005 Environmental Scan provides an aggregate synopsis of the key trends which will impact on Ontario's Colleges of Applied Arts and Technology in the future and will assist colleges in their advocacy and strategic planning…

  9. The need for environmental horizon scanning.

    PubMed

    Sutherland, William J; Woodroof, Harry J

    2009-10-01

    Policymakers and practitioners in most fields, including conservation and the environment, often make decisions based on insufficient evidence. One reason for this is that issues appear unexpectedly, when with hindsight, many of them were foreseeable. A solution to the problem of being insufficiently prepared is routine horizon scanning, which we describe as the systematic search for potential threats and opportunities that are currently poorly recognized. Researchers can then decide which issues might be most worthwhile to study. Practitioners can also use horizon scanning to ensure timely policy development and research procurement. Here, we suggest that horizon scanning is an underused tool that should become a standard element of environmental and conservation practice. We make recommendations for its incorporation into research, policy and practice. We argue that, as an ecological and conservation community, we are failing to provide timely advice owing to a weakness in identifying forthcoming issues. We outline possible horizon-scanning methods, and also make recommendations as to how horizon scanning could have a more central role in environmental and conservation practice.

  10. Environmental scanning electron microscopy in cell biology.

    PubMed

    McGregor, J E; Staniewicz, L T L; Guthrie Neé Kirk, S E; Donald, A M

    2013-01-01

    Environmental scanning electron microscopy (ESEM) (1) is an imaging technique which allows hydrated, insulating samples to be imaged under an electron beam. The resolution afforded by this technique is higher than conventional optical microscopy but lower than conventional scanning electron microscopy (CSEM). The major advantage of the technique is the minimal sample preparation needed, making ESEM quick to use and the images less susceptible to the artifacts that the extensive sample preparation usually required for CSEM may introduce. Careful manipulation of both the humidity in the microscope chamber and the beam energy are nevertheless essential to prevent dehydration and beam damage artifacts. In some circumstances it is possible to image live cells in the ESEM (2).In the following sections we introduce the fundamental principles of ESEM imaging before presenting imaging protocols for plant epidermis, mammalian cells, and bacteria. In the first two cases samples are imaged using the secondary electron (topographic) signal, whereas a transmission technique is employed to image bacteria.

  11. Environmental Scanning Workshop (Lansing, Michigan, June 10-11, 1992).

    ERIC Educational Resources Information Center

    Morrison, James L.

    This publication presents an environmental scanning workshop for administrators in higher education institutions to help them incorporate environmental scanning into their planning and anticipation of future events. In particular, the workshop shows how to establish and sustain a comprehensive environmental scanning system and how to use the…

  12. Environmental Scan for the Colorado Community College System.

    ERIC Educational Resources Information Center

    2003

    This document addresses an environmental scan done in the Colorado Community College System (CCCS). The goals of an environmental scan include collecting external information, predicting future trends, and analyzing how these trends might affect an organization. The environmental scan completed for the CCCS focused on emerging trends that may…

  13. Environmental scan of cystic fibrosis research worldwide.

    PubMed

    Kelly, Janice

    2017-05-01

    Cystic fibrosis (CF) is a rare fatal genetic disease, affecting 70,000 to 100,000 people worldwide [1]. Numerous countries have specific charitable organizations dedicated to CF, with many funding research to find a cure or effective control for the disease. Cystic Fibrosis Canada, the largest charity in Canada dedicated to funding research and care in CF, conducted an environmental scan of these organizations to learn and better understand their research goals and funding process. A set of questions was sent to 25 CF charitable organizations around the world by email. Responses were consolidated to identify common practices and innovative approaches. Among respondents, there were variations in the amount of funds invested in research annually and the number of studies supported. Common themes identified included practicing an open call for research applications, evaluating applications using a peer review process, and placing an increased emphasis on patient engagement. Innovative approaches included funding one larger project; funding a series of sub-projects on a common theme; partially funding a research project; and, indefinitely funding part of a researcher's salary. Among CF charitable organizations, there are numerous approaches to research funding. Both similarities and differences were noted between these organizations, all of which share the common goal of working towards improving quality of life and survival for people with CF. Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  14. Environmental Scan: Literacy Work in Canada. Summary Report

    ERIC Educational Resources Information Center

    Movement for Canadian Literacy, 2007

    2007-01-01

    During the fall of 2007, Movement for Canadian Literacy (MCL) conducted an environmental scan of the Anglophone literacy field in Canada. Data was gathered through the use of key informant interviews (19) and a literature review. A cross-national working group guided the development of the scan. Interviews with key informants for the scan revealed…

  15. Focus on the Future: Environmental Scanning at Columbia Basin College.

    ERIC Educational Resources Information Center

    Knutzen, Judi, Comp.

    As the first step of the process of developing a strategic plan, the Institutional Research Director at Columbia Basin College (Washington) was asked to perform an environmental scan. Environmental scanning is a careful and continuous process of tracking and analyzing trends relevant to an institution's goals. It involves making forecasts of…

  16. [Environmental scanning electron microscopy for biofilm detection in tonsils].

    PubMed

    Ramírez-Camacho, Rafael; González-Tallón, Ana Isabel; Gómez, David; Trinidad, Almudena; Ibáñez, Andrés; García-Berrocal, José Ramón; Verdaguer, José María; González-García, José Angel; San Román, Julio

    2008-01-01

    To describe an environmental scanning electron microscopic method for the study of biofilms in clinical samples. A comparison with standard scanning electron microscopy is performed. Nine patients with a past history of recurrent tonsillitis underwent tonsillectomy. Samples from each patient were obtained for both conventional and environmental scanning electron microscopy. The tonsils removed from 2 patients with sleep apnoea syndrome were used as controls. Eight of nine tonsils had biofilms on their surface. Scanning electron microscopy showed accumulations of bacteria covered by fibrillar structures resulting from the sample dehydration process. Environmental scanning electron microscopy provided a view of bacteria embedded in a homogeneous, amorphous substance that was preserved during the examination. Environmental scanning electron microscopy permits the imaging of wet systems at different degrees of dehydration. It therefore allows researchers to observe biofilms in their natural hydrated state.

  17. Kinematic analysis of conically scanned environmental properties

    NASA Technical Reports Server (NTRS)

    Wilkerson, Thomas D. (Inventor); Sanders, Jason A. (Inventor); Andrus, Ionio Q. (Inventor)

    2003-01-01

    A method for determining the velocity of features such as wind. The method preferably includes producing sensor signals and projecting the sensor signals sequentially along lines lying on the surface of a cone. The sensor signals may be in the form of lidar, radar or sonar for example. As the sensor signals are transmitted, the signals contact objects and are backscattered. The backscattered sensor signals are received to determine the location of objects as they pass through the transmission path. The speed and direction the object is moving may be calculated using the backscattered data. The data may be plotted in a two dimensional array with a scan angle on one axis and a scan time on the other axis. The prominent curves that appear in the plot may be analyzed to determine the speed and direction the object is traveling.

  18. Environmental Scanning on a Shoe-String Budget.

    ERIC Educational Resources Information Center

    Kramer, Arthur

    An environmental scan was conducted to assess the demographic and economic conditions in Passaic County (New Jersey) as a way of providing information helpful to Passaic County Community College (PCCC) in its planning activities. The environment scan focused on immigration patterns, job creation and loss trends, business hiring needs, PCCC…

  19. Environmental Scan of BC Post-Secondary Admissions: 2009

    ERIC Educational Resources Information Center

    Heath, Nick

    2009-01-01

    In 2008, British Columbia Council on Admissions and Transfer (BCCAT) commissioned an environmental scan on the possible need for system-wide work on institutional admissions processes and practices. This scan is intended to seek system input and to provide guidance on the choice of research projects and other related work in the coming year. This…

  20. 2020 Perfect Vision for the Next Century: An Environmental Scan.

    ERIC Educational Resources Information Center

    Friedel, Jan

    Focusing on the future of the Eastern Iowa Community College District (EICCD), this environmental scan examines changes occurring in both local and worldwide populations and workforces; political, societal, and economic environs; and technology. Section I describes the changing population and demographics in the United States, focusing on the…

  1. Information Source Characteristics and Environmental Scanning by Academic Library Managers

    ERIC Educational Resources Information Center

    Babalhavaeji, Fahimeh; Farhadpoor, Mohammad Reza

    2013-01-01

    Purpose: This article examines characteristics of the external environment of library and information centres of Islamic Azad University in Iran, focusing on perceived environmental uncertainty and perceived source accessibility and quality, and their impacts on the amount of scanning and the frequency of information source use. Methods: This…

  2. An Environmental Scan of Adventure Therapy in Canada

    ERIC Educational Resources Information Center

    Ritchie, Stephen D.; Patrick, Krysten; Corbould, Gordon Marcus; Harper, Nevin J.; Oddson, Bruce E.

    2016-01-01

    We report on an environmental scan (ES) of adventure therapy (AT) literature, organizations, and activities in Canada. The ES methodology involved (a) an examination of final reports related to a series of national symposiums on AT in Canada, (b) a review of academic literature related to AT in Canada, and (c) a summary of AT programs and courses…

  3. An Environmental Scan of Adventure Therapy in Canada

    ERIC Educational Resources Information Center

    Ritchie, Stephen D.; Patrick, Krysten; Corbould, Gordon Marcus; Harper, Nevin J.; Oddson, Bruce E.

    2016-01-01

    We report on an environmental scan (ES) of adventure therapy (AT) literature, organizations, and activities in Canada. The ES methodology involved (a) an examination of final reports related to a series of national symposiums on AT in Canada, (b) a review of academic literature related to AT in Canada, and (c) a summary of AT programs and courses…

  4. Environmental scanning electron microscope imaging examples related to particle analysis.

    PubMed

    Wight, S A; Zeissler, C J

    1993-08-01

    This work provides examples of some of the imaging capabilities of environmental scanning electron microscopy applied to easily charged samples relevant to particle analysis. Environmental SEM (also referred to as high pressure or low vacuum SEM) can address uncoated samples that are known to be difficult to image. Most of these specimens are difficult to image by conventional SEM even when coated with a conductive layer. Another area where environmental SEM is particularly applicable is for specimens not compatible with high vacuum, such as volatile specimens. Samples from which images were obtained that otherwise may not have been possible by conventional methods included fly ash particles on an oiled plastic membrane impactor substrate, a one micrometer diameter fiber mounted on the end of a wire, uranium oxide particles embedded in oil-bearing cellulose nitrate, teflon and polycarbonate filter materials with collected air particulate matter, polystyrene latex spheres on cellulosic filter paper, polystyrene latex spheres "loosely" sitting on a glass slide, and subsurface tracks in an etched nuclear track-etch detector. Surface charging problems experienced in high vacuum SEMs are virtually eliminated in the low vacuum SEM, extending imaging capabilities to samples previously difficult to use or incompatible with conventional methods.

  5. Miniaturized Environmental Scanning Electron Microscope for In Situ Planetary Studies

    NASA Technical Reports Server (NTRS)

    Gaskin, Jessica; Abbott, Terry; Medley, Stephanie; Gregory, Don; Thaisen, Kevin; Taylor , Lawrence; Ramsey, Brian; Jerman, Gregory; Sampson, Allen; Harvey, Ralph

    2010-01-01

    The exploration of remote planetary surfaces calls for the advancement of low power, highly-miniaturized instrumentation. Instruments of this nature that are capable of multiple types of analyses will prove to be particularly useful as we prepare for human return to the moon, and as we continue to explore increasingly remote locations in our Solar System. To this end, our group has been developing a miniaturized Environmental-Scanning Electron Microscope (mESEM) capable of remote investigations of mineralogical samples through in-situ topographical and chemical analysis on a fine scale. The functioning of an SEM is well known: an electron beam is focused to nanometer-scale onto a given sample where resulting emissions such as backscattered and secondary electrons, X-rays, and visible light are registered. Raster scanning the primary electron beam across the sample then gives a fine-scale image of the surface topography (texture), crystalline structure and orientation, with accompanying elemental composition. The flexibility in the types of measurements the mESEM is capable of, makes it ideally suited for a variety of applications. The mESEM is appropriate for use on multiple planetary surfaces, and for a variety of mission goals (from science to non-destructive analysis to ISRU). We will identify potential applications and range of potential uses related to planetary exploration. Over the past few of years we have initiated fabrication and testing of a proof-of-concept assembly, consisting of a cold-field-emission electron gun and custom high-voltage power supply, electrostatic electron-beam focusing column, and scanning-imaging electronics plus backscatter detector. Current project status will be discussed. This effort is funded through the NASA Research Opportunities in Space and Earth Sciences - Planetary Instrument Definition and Development Program.

  6. Environmental scanning electron microscopy gold immunolabeling in cell biology.

    PubMed

    Rosso, Francesco; Papale, Ferdinando; Barbarisi, Alfonso

    2013-01-01

    Immunogold labeling (IGL) technique has been utilized by many authors in combination with scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to obtain the identification/localization of receptors and antigens, both in cells and tissues. Environmental scanning electron microscopy (ESEM) represents an important tool in biomedical research, since it does not require any severe processing of the sample, lowering the risk of generating artifacts and interfere with the IGL procedure. The absence of metal coating could yield further advantages for our purpose as the labeling detection is based on the atomic number difference between nanogold spheres and the biological material. Using the gaseous secondary electron detector, compositional contrast is easily revealed by the backscattered electron component of the signal. In spite of this fact, only few published papers present a combination of ESEM and IGL. Hereby we present our method, optimized to improve the intensity and the specificity of the labeling signal, in order to obtain a semiquantitative evaluation of the labeling signal.In particular, we used a combination of IGL and ESEM to detect the presence of a protein on the cell surface. To achieve this purpose, we chose as an experimental system 3T3 Swiss albino mouse fibroblasts and galectin-3.

  7. Probing Individual Ice Nucleation Events with Environmental Scanning Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Wang, Bingbing; China, Swarup; Knopf, Daniel; Gilles, Mary; Laskin, Alexander

    2016-04-01

    Heterogeneous ice nucleation is one of the processes of critical relevance to a range of topics in the fundamental and the applied science and technologies. Heterogeneous ice nucleation initiated by particles proceeds where microscopic properties of particle surfaces essentially control nucleation mechanisms. Ice nucleation in the atmosphere on particles governs the formation of ice and mixed phase clouds, which in turn influence the Earth's radiative budget and climate. Heterogeneous ice nucleation is still insufficiently understood and poses significant challenges in predictive understanding of climate change. We present a novel microscopy platform allowing observation of individual ice nucleation events at temperature range of 193-273 K and relative humidity relevant for ice formation in the atmospheric clouds. The approach utilizes a home built novel ice nucleation cell interfaced with Environmental Scanning Electron Microscope (IN-ESEM system). The IN-ESEM system is applied for direct observation of individual ice formation events, determining ice nucleation mechanisms, freezing temperatures, and relative humidity onsets. Reported microanalysis of the ice nucleating particles (INP) include elemental composition detected by the energy dispersed analysis of X-rays (EDX), and advanced speciation of the organic content in particles using scanning transmission x-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). The performance of the IN-ESEM system is validated through a set of experiments with kaolinite particles with known ice nucleation propensity. We demonstrate an application of the IN-ESEM system to identify and characterize individual INP within a complex mixture of ambient particles.

  8. Environmental Scanning Electron Microscope Imaging of Vesicle Systems.

    PubMed

    Perrie, Yvonne; Ali, Habib; Kirby, Daniel J; Mohammed, Afzal U R; McNeil, Sarah E; Vangala, Anil

    2017-01-01

    The structural characteristics of liposomes have been widely investigated and there is certainly a strong understanding of their morphological characteristics. Imaging of these systems, using techniques such as freeze-fracturing methods, transmission electron microscopy, and cryo-electron imaging, has allowed us to appreciate their bilayer structures and factors which can influence this. However, there are few methods which all us to study these systems in their natural hydrated state; commonly the liposomes are visualized after drying, staining, and/or fixation of the vesicles. Environmental Scanning Electron Microscopy (ESEM) offers the ability to image a liposome in its hydrated state without the need for prior sample preparation. Within our studies we were the first to use ESEM to study liposomes and niosomes and we have been able to dynamically follow the hydration of lipid films and changes in liposome suspensions as water condenses on to, or evaporates from, the sample in real time. This provides insight into the resistance of liposomes to coalescence during dehydration, thereby providing an alternative assay of liposome formulation and stability.

  9. An international environmental scan of quality indicators for cardiovascular care.

    PubMed

    Abrahamyan, Lusine; Boom, Nicole; Donovan, Linda R; Tu, Jack V

    2012-01-01

    Quality indicators (QIs) are increasingly being used to measure and improve the quality of cardiac care. We conducted an international environmental scan to identify and critically appraise published QI development initiatives addressing cardiovascular disease (CVD). A review of the peer-reviewed and grey English-language literature was conducted to identify published CVD QI development initiatives. The quality of identified studies was assessed using a modified version of the Appraisal of Guidelines for Research and Evaluation (AGREE) II QI tool-an instrument originally developed for the assessment of the quality of clinical practice guidelines. An initial literature search identified 2314 potentially relevant abstracts of peer-reviewed articles. After a review of the abstracts, 120 full text articles were retrieved and reviewed. Of these, 20 articles and 1 peer-reviewed monograph were selected for critical appraisal (n = 21). Most of the initiatives were conducted in North America (76%) and were published after 2005 (62%). The majority (5 of 6) of the AGREE II QI domain scores were skewed toward higher values, including the median score for the 'overall quality' rating (83.3%). Of the CVD categories addressed within the 21 initiatives, heart failure was the most common (n = 10 QI indicator sets), followed by acute coronary syndromes (n = 8). Considerable variation was observed in the methods utilized and the degree of scientific rigour applied in the published international CVD QI development initiatives. Adoption of standardized methods could help improve the quality of QI development initiatives.

  10. Characterization of humic substances by environmental scanning electron microscopy.

    PubMed

    Redwood, Paul S; Lead, Jamie R; Harrison, Roy M; Jones, Ian P; Stoll, Serge

    2005-04-01

    Environmental scanning electron microscopy (ESEM) is a new technique capable of imaging micron and submicron particles. Here, we have applied it to image and quantify natural aquatic organic matter (standard Suwannee River humic acid, SRHA). Uniquely, we have observed the humic aggregate structures as a function of humidity and pH. Large aggregates of tens of micrometers were observed as the dominant material under all conditions, although much smaller material was also observed. Fractal dimensions (D) were calculated between 1.48 and 1.70, although these values were not statistically different under conditions of low humidity. However, D values calculated at high humidities (85%) during the rehydration phase were significantly lower (1.48+/-0.01) than in the initial dehydration phase (1.69+/-0.01). This hysteresis indicated that full rehydration of the HS was either kinetically slow or irreversible after dehydration. Fractal analysis of ESEM images was also performed to probe the change in aggregate structure as a function of pH. Minimum values were calculated at neutral pHs, rising by 0.1-0.2 at both high and low pHs because of a combination of the physical chemistry of HS and the impacts of the drying regime within the ESEM. Thus, ESEM was an important complementary technique to other analytical methods. At present, ESEM cannot be used to image nonperturbed natural samples. However, the method is an ideal method for probing the changes in colloid structure as function of hydration state and has the potential to perform fully quantitative and nonperturbing analysis of colloidal structure.

  11. Establishing an Environmental Scanning/Forecasting System to Augment College and University Planning.

    ERIC Educational Resources Information Center

    Morrison, James L.

    1987-01-01

    The major benefit of an environmental scanning/forecasting system is in providing critical information for strategic planning. Such a system allows the institution to detect social, technological, economic, and political trends and potential events. The environmental scanning database developed by United Way of America is described. (MLW)

  12. Developing Environmental Scanning/Forecasting Systems To Augment Community College Planning.

    ERIC Educational Resources Information Center

    Morrison, James L.; Held, William G.

    A description is provided of a conference session that was conducted to explore the structure and function of an environmental scanning/forecasting system that could be used in a community college to facilitate planning. Introductory comments argue that a college that establishes an environmental scanning and forecasting system is able to identify…

  13. SCAN+

    SciTech Connect

    Kenneth Krebs, John Svoboda

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determine the positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.

  14. Environmental Scanning as a Public Health Tool: Kentucky’s Human Papillomavirus Vaccination Project

    PubMed Central

    Wilburn, Amanda; Knight, Jennifer R.

    2016-01-01

    Borrowing from business, quality improvement programs, and strategic planning principles, environmental scanning is gaining popularity in public health practice and research and is advocated as an assessment and data collection tool by federal funding agencies and other health-related organizations. Applicable to a range of current and emerging health topics, environmental scans — through various methods — assess multiple facets of an issue by engaging stakeholders who can ask or answer research questions, exploring related policy, critiquing published and gray literature, collecting and analyzing qualitative and quantitative data in both primary and secondary forms, disseminating findings to internal and external stakeholders, and informing subsequent planning and decision making. To illustrate the environmental scanning process in a public health setting and showcase its value to practitioners in the field, we describe a federally funded environmental scan for a human papillomavirus vaccination project in Kentucky. PMID:27536901

  15. The Environmental Scan Component of the Strategic Plan for California Community Colleges.

    ERIC Educational Resources Information Center

    Hom, Willard

    This paper describes the environmental scan that the California Community Colleges Chancellor's Office initiated in preparation for its development of a strategic plan. In this scanning effort, environment is defined as "a search for information about the system's external setting." The trends are roughly grouped into five areas:…

  16. The Necessity of Environmental Scanning Prior to Long-Range Planning Activities at Higher Education Institutions.

    ERIC Educational Resources Information Center

    Handy, Ty J.

    Formal environmental scanning procedures can provide key administrators of higher education institutions with valuable external information regarding both the probability and impact of external trends and forces. Such information may then be used in various strategic planning stages including scenario development, institutional mission and goals…

  17. An Environmental Scan Update, 1992-93. 2020: Perfect Vision for the Next Century.

    ERIC Educational Resources Information Center

    Friedel, J. N., Ed.

    1992-01-01

    A key component to Eastern Iowa Community College District's (EICCD) strategic planning process, called "2020 Vision: A Perfect Vision for the Future," was the publication of the report "An Environmental Scan" in 1989, which summarized major trends occurring in the external environment which may impact the community college,…

  18. Environmental Scan of Weight Bias Exposure in Primary Health Care Training Programs

    ERIC Educational Resources Information Center

    Russell-Mayhew, Shelly; Nutter, Sarah; Alberga, Angela; Jelinski, Susan; Ball, Geoff D. C.; Edwards, Alun; Oddie, Scott; Sharma, Arya M.; Pickering, Barbara; Forhan, Mary

    2016-01-01

    Negative attitudes and beliefs about individuals with obesity (also known as weight bias) have negative consequences for physical and mental health for individuals with obesity and impact the quality of care provided by health professionals. A preliminary environmental scan of college and university training programs was conducted consisting of 67…

  19. Association of Colleges of Applied Arts and Technology of Ontario 2001 Environmental Scan.

    ERIC Educational Resources Information Center

    Association of Colleges of Applied Arts and Technology of Ontario, Toronto.

    The 2001 Environmental Scan for the Colleges of Applied Arts and Technology of Ontario is designed to assist colleges in their strategic planning processes. It provides information about economy and labor, various trends in education and training, postsecondary enrollment and demographics, transfer payments and operating grants, Ontario's…

  20. Higher Learning and the Labour Market in a Changing World: Environmental Scan for British Columbia

    ERIC Educational Resources Information Center

    Ministry of Advanced Education, 2008

    2008-01-01

    In a knowledge-based economy, economic and social well-being depend on the development of human resources, and those with access to education benefit from higher lifetime earnings, lower rates of unemployment and poverty, a greater sense of engagement at work and society, and healthier lifestyles. This environmental scan considers the major…

  1. Association of Colleges of Applied Arts and Technology of Ontario 2002 Environmental Scan.

    ERIC Educational Resources Information Center

    Association of Colleges of Applied Arts and Technology of Ontario, Toronto.

    This environmental scan is designed to assist Ontario's colleges in their strategic planning processes. Ontario's colleges have supported a 35% increase in enrollment, with a 40% decrease in funding, over the last ten years, while operating costs have risen. In addition, Ontario eliminated the secondary school Ontario Academic Courses (OACs),…

  2. Looking Beyond School Walls: An Environmental Scan of Minneapolis Public Schools, 2004-2008

    ERIC Educational Resources Information Center

    Alexander, Nicola A.; Choi, Wonseok

    2015-01-01

    We provide an expanded environmental scan to assess the strengths, weaknesses, opportunities, and threats (SWOT) faced by education communities. Grounded in the literature, we identified 48 indicators and grouped them into 6 broad categories: (1) budget levels, (2) funding patterns, (3) community needs, (4) external economic conditions, (5)…

  3. Higher Learning and the Labour Market in a Changing World: Environmental Scan for British Columbia

    ERIC Educational Resources Information Center

    Ministry of Advanced Education, 2008

    2008-01-01

    In a knowledge-based economy, economic and social well-being depend on the development of human resources, and those with access to education benefit from higher lifetime earnings, lower rates of unemployment and poverty, a greater sense of engagement at work and society, and healthier lifestyles. This environmental scan considers the major…

  4. Using GIS Tools and Environmental Scanning to Forecast Industry Workforce Needs

    ERIC Educational Resources Information Center

    Gaertner, Elaine; Fleming, Kevin; Marquez, Michelle

    2009-01-01

    The Centers of Excellence (COE) provide regional workforce data on high growth, high demand industries and occupations for use by community colleges in program planning and resource enhancement. This article discusses the environmental scanning research methodology and its application to data-driven decision making in community college program…

  5. Variables Associated with Environmental Scanning among Clinicians at Substance Abuse Treatment Clinics

    ERIC Educational Resources Information Center

    Koch, Alison L.; Arfken, Cynthia L.; Agius, Elizabeth; Dickson, Marcus W.; Mitchelson, Jacqueline K.

    2005-01-01

    Introduction: Environmental scanning, as a component of absorptive capacity, has been shown to be associated with increased use of innovative treatment techniques at substance abuse treatment programmes. As the transfer of innovative, evidence-based treatment techniques from research to practice is gaining attention, we aimed to identify variables…

  6. Using GIS Tools and Environmental Scanning to Forecast Industry Workforce Needs

    ERIC Educational Resources Information Center

    Gaertner, Elaine; Fleming, Kevin; Marquez, Michelle

    2009-01-01

    The Centers of Excellence (COE) provide regional workforce data on high growth, high demand industries and occupations for use by community colleges in program planning and resource enhancement. This article discusses the environmental scanning research methodology and its application to data-driven decision making in community college program…

  7. Developing an Environmental Scanning System in an Educational Organization: Lessons Learned. AIR 1990 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Morrison, James L.; Ptaszynski, James G.

    An environmental scanning system was developed by the admissions office of a graduate school of management in a small southeastern university. The school's strategic planning committee felt that it would be beneficial to acquire information concerning issues, trends, and possible events that might impact upon the school in the future and to…

  8. INNOVATIVE TECHNOLOGY VERIFICATION REPORT "FIELD MEASUREMENT TECHNOLOGIES FOR TOTAL PETROLEUM HYDROCARBONS IN SOIL" ENVIRONMENTAL SYSTEMS CORPORATION SYNCHRONOUS SCANNING LUMINOSCOPE

    EPA Science Inventory


    The Synchronous Scanning Luminoscope (Luminoscope) developed by the Oak Ridge National Laboratory in collaboration with Environmental Systems Corporation (ESC) was demonstrated under the U.S. Environmental Protection Agency Superfund Innovative Technology Evaluation Program i...

  9. INNOVATIVE TECHNOLOGY VERIFICATION REPORT "FIELD MEASUREMENT TECHNOLOGIES FOR TOTAL PETROLEUM HYDROCARBONS IN SOIL" ENVIRONMENTAL SYSTEMS CORPORATION SYNCHRONOUS SCANNING LUMINOSCOPE

    EPA Science Inventory


    The Synchronous Scanning Luminoscope (Luminoscope) developed by the Oak Ridge National Laboratory in collaboration with Environmental Systems Corporation (ESC) was demonstrated under the U.S. Environmental Protection Agency Superfund Innovative Technology Evaluation Program i...

  10. Environmental Scanning for Occupational Education. A Facilitator's Guide. A Model for Environmental Scanning to Systematically Assess Future Occupational Education and Training Needs of a Michigan Community College Service Area.

    ERIC Educational Resources Information Center

    Kellogg Foundation, Battle Creek, MI.

    This manual is designed to facilitate the planning and implementation of an environmental scanning project in Michigan's community colleges. (Environmental scanning is a systematic process for gathering and analyzing information about the external environment and relating it to an organization's internal environment.) This facilitator's guide is…

  11. Statistical Characterization of Environmental Error Sources Affecting Electronically Scanned Pressure Transducers

    NASA Technical Reports Server (NTRS)

    Green, Del L.; Walker, Eric L.; Everhart, Joel L.

    2006-01-01

    Minimization of uncertainty is essential to extend the usable range of the 15-psid Electronically Scanned Pressure [ESP) transducer measurements to the low free-stream static pressures found in hypersonic wind tunnels. Statistical characterization of environmental error sources inducing much of this uncertainty requires a well defined and controlled calibration method. Employing such a controlled calibration system, several studies were conducted that provide quantitative information detailing the required controls needed to minimize environmental and human induced error sources. Results of temperature, environmental pressure, over-pressurization, and set point randomization studies for the 15-psid transducers are presented along with a comparison of two regression methods using data acquired with both 0.36-psid and 15-psid transducers. Together these results provide insight into procedural and environmental controls required for long term high-accuracy pressure measurements near 0.01 psia in the hypersonic testing environment using 15-psid ESP transducers.

  12. Statistical Characterization of Environmental Error Sources Affecting Electronically Scanned Pressure Transducers

    NASA Technical Reports Server (NTRS)

    Green, Del L.; Walker, Eric L.; Everhart, Joel L.

    2006-01-01

    Minimization of uncertainty is essential to extend the usable range of the 15-psid Electronically Scanned Pressure (ESP) transducer measurements to the low free-stream static pressures found in hypersonic wind tunnels. Statistical characterization of environmental error sources inducing much of this uncertainty requires a well defined and controlled calibration method. Employing such a controlled calibration system, several studies were conducted that provide quantitative information detailing the required controls needed to minimize environmental and human induced error sources. Results of temperature, environmental pressure, over-pressurization, and set point randomization studies for the 15-psid transducers are presented along with a comparison of two regression methods using data acquired with both 0.36-psid and 15-psid transducers. Together these results provide insight into procedural and environmental controls required for long term high-accuracy pressure measurements near 0.01 psia in the hypersonic testing environment using 15-psid ESP transducers.

  13. Health literacy environmental scans of community-based dental clinics in Maryland.

    PubMed

    Horowitz, Alice M; Maybury, Catherine; Kleinman, Dushanka V; Radice, Sarah D; Wang, Min Qi; Child, Wendy; Rudd, Rima E

    2014-08-01

    We conducted health literacy environmental scans in 26 Maryland community-based dental clinics to identify institutional characteristics and provider practices that affect dental services access and dental caries education. In 2011-2012 we assessed user friendliness of the clinics including accessibility, signage, facility navigation, educational materials, and patient forms. We interviewed patients and surveyed dental providers about their knowledge and use of communication techniques. Of 32 clinics, 26 participated. Implementation of the health literacy environmental scan tools was acceptable to the dental directors and provided clinic directors with information to enhance care and outreach. We found considerable variation among clinic facilities, operations, and content of educational materials. There was less variation in types of insurance accepted, no-show rates, methods of communicating with patients, and electronic health records use. Providers who had taken a communication skills course were more likely than those who had not to use recommended communication techniques. Our findings provide insight into the use of health literacy environmental scan tools to identify clinic and provider characteristics and practices that can be used to make dental environments more user friendly and health literate.

  14. Health Literacy Environmental Scans of Community-Based Dental Clinics in Maryland

    PubMed Central

    Maybury, Catherine; Kleinman, Dushanka V.; Radice, Sarah D.; Wang, Min Qi; Child, Wendy; Rudd, Rima E.

    2014-01-01

    Objectives. We conducted health literacy environmental scans in 26 Maryland community-based dental clinics to identify institutional characteristics and provider practices that affect dental services access and dental caries education. Methods. In 2011–2012 we assessed user friendliness of the clinics including accessibility, signage, facility navigation, educational materials, and patient forms. We interviewed patients and surveyed dental providers about their knowledge and use of communication techniques. Results. Of 32 clinics, 26 participated. Implementation of the health literacy environmental scan tools was acceptable to the dental directors and provided clinic directors with information to enhance care and outreach. We found considerable variation among clinic facilities, operations, and content of educational materials. There was less variation in types of insurance accepted, no-show rates, methods of communicating with patients, and electronic health records use. Providers who had taken a communication skills course were more likely than those who had not to use recommended communication techniques. Conclusions. Our findings provide insight into the use of health literacy environmental scan tools to identify clinic and provider characteristics and practices that can be used to make dental environments more user friendly and health literate. PMID:24922128

  15. The utility of the environmental scan for public health practice: lessons from an urban program to increase cancer screening.

    PubMed Central

    Rowel, Randolph; Moore, Natalie Dewberry; Nowrojee, Sia; Memiah, Peter; Bronner, Yvonne

    2005-01-01

    The environmental scan is a tool that can be utilized to collect data to design health programs uniquely tailored to the needs of communities. However, it remains relatively undefined, unevaluated and underutilized in the field of public health. While individual studies indicate the utility of the environmental scan for public health, it is difficult to find a theoretical framework or guidelines on how to design, implement or evaluate the process within public health practice. The purpose of this study was to elicit lessons learned to maximize the utility of the environmental scan as a tool for public health. This process occurred through the development and implementation of an environmental scan as part of the needs-assessment phase of a project to increase cancer screening among African Americans in Baltimore, MD. Data collection methods for the environmental scan included a review of community stakeholders, cancer incidence and community assets and liabilities in target communities, focus-group sessions and key informant interviews with service providers. The environmental scan was conducted in 2003 and allowed for rapid acquisition and use of information about events, trends and relationships in the neighborhoods targeted for our project and enabled researchers to move forward with implementing the cancer-screening project. The researchers conclude that the environmental scan has considerable potential to be a creative, responsive, cost-effective and mobilizing tool for public health practice. However, further application and critical review are necessary to make it a more effective public health tool and an established research methodology. PMID:15868772

  16. Epidermal growth factor receptor subunit locations determined in hydrated cells with environmental scanning electron microscopy.

    PubMed

    Peckys, Diana B; Baudoin, Jean-Pierre; Eder, Magdalena; Werner, Ulf; de Jonge, Niels

    2013-01-01

    Imaging single epidermal growth factor receptors (EGFR) in intact cells is presently limited by the available microscopy methods. Environmental scanning electron microscopy (ESEM) of whole cells in hydrated state in combination with specific labeling with gold nanoparticles was used to localize activated EGFRs in the plasma membranes of COS7 and A549 cells. The use of a scanning transmission electron microscopy (STEM) detector yielded a spatial resolution of 3 nm, sufficient to identify the locations of individual EGFR dimer subunits. The sizes and distribution of dimers and higher order clusters of EGFRs were determined. The distance between labels bound to dimers amounted to 19 nm, consistent with a molecular model. A fraction of the EGFRs was found in higher order clusters with sizes ranging from 32-56 nm. ESEM can be used for quantitative whole cell screening studies of membrane receptors, and for the study of nanoparticle-cell interactions in general.

  17. Epidermal growth factor receptor subunit locations determined in hydrated cells with environmental scanning electron microscopy

    PubMed Central

    Peckys, Diana B.; Baudoin, Jean-Pierre; Eder, Magdalena; Werner, Ulf; de Jonge, Niels

    2013-01-01

    Imaging single epidermal growth factor receptors (EGFR) in intact cells is presently limited by the available microscopy methods. Environmental scanning electron microscopy (ESEM) of whole cells in hydrated state in combination with specific labeling with gold nanoparticles was used to localize activated EGFRs in the plasma membranes of COS7 and A549 cells. The use of a scanning transmission electron microscopy (STEM) detector yielded a spatial resolution of 3 nm, sufficient to identify the locations of individual EGFR dimer subunits. The sizes and distribution of dimers and higher order clusters of EGFRs were determined. The distance between labels bound to dimers amounted to 19 nm, consistent with a molecular model. A fraction of the EGFRs was found in higher order clusters with sizes ranging from 32–56 nm. ESEM can be used for quantitative whole cell screening studies of membrane receptors, and for the study of nanoparticle-cell interactions in general. PMID:24022088

  18. THE INTEGRATED USE OF COMPUTATIONAL CHEMISTRY, SCANNING PROBE MICROSCOPY, AND VIRTUAL REALITY TO PREDICT THE CHEMICAL REACTIVITY OF ENVIRONMENTAL SURFACES

    EPA Science Inventory

    In the last decade three new techniques scanning probe microscopy (SPM), virtual reality (YR) and computational chemistry ave emerged with the combined capability of a priori predicting the chemically reactivity of environmental surfaces. Computational chemistry provides the cap...

  19. THE INTEGRATED USE OF COMPUTATIONAL CHEMISTRY, SCANNING PROBE MICROSCOPY, AND VIRTUAL REALITY TO PREDICT THE CHEMICAL REACTIVITY OF ENVIRONMENTAL SURFACES

    EPA Science Inventory

    In the last decade three new techniques scanning probe microscopy (SPM), virtual reality (YR) and computational chemistry ave emerged with the combined capability of a priori predicting the chemically reactivity of environmental surfaces. Computational chemistry provides the cap...

  20. Electron transparent graphene windows for environmental scanning electron microscopy in liquids and dense gases.

    PubMed

    Stoll, Joshua D; Kolmakov, Andrei

    2012-12-21

    Due to its ultrahigh electron transmissivity in a wide electron energy range, molecular impermeability, high electrical conductivity and excellent mechanical stiffness, suspended graphene membranes appear to be a nearly ideal window material for in situ (in vivo) environmental electron microscopy of nano- and mesoscopic objects (including bio-medical samples) immersed in liquids and/or in dense gaseous media. In this paper, taking advantage of a small modification of the graphene transfer protocol onto metallic and SiN supporting orifices, reusable environmental cells with exchangeable graphene windows have been designed. Using colloidal gold nanoparticles (50 nm) dispersed in water as model objects for scanning electron microscopy in liquids as proof of concept, different conditions for imaging through the graphene membrane were tested. Limiting factors for electron microscopy in liquids, such as electron beam induced water radiolysis and damage of the graphene membrane at high electron doses, are discussed.

  1. Geostationary Operational Environmental Satellite (GOES)-14 super rapid scan operations to prepare for GOES-R

    NASA Astrophysics Data System (ADS)

    Schmit, Timothy J.; Goodman, Steven J.; Lindsey, Daniel T.; Rabin, Robert M.; Bedka, Kristopher M.; Gunshor, Mathew M.; Cintineo, John L.; Velden, Christopher S.; Scott Bachmeier, A.; Lindstrom, Scott S.; Schmidt, Christopher C.

    2013-01-01

    Geostationary Operational Environmental Satellite (GOES)-14 imager was operated by National Oceanic and Atmospheric Administration (NOAA) in an experimental rapid scan 1-min mode that emulates the high-temporal resolution sampling of the Advanced Baseline Imager (ABI) on the next generation GOES-R series. Imagery with a refresh rate of 1 min of many phenomena were acquired, including clouds, convection, fires, smoke, and hurricanes, including 6 days of Hurricane Sandy through landfall. NOAA had never before operated a GOES in a nearly continuous 1-min mode for such an extended period of time, thereby making these unique datasets to explore the future capabilities possible with GOES-R. The next generation GOES-R imager will be able to routinely take mesoscale (1000 km×1000 km) images every 30 s (or two separate locations every minute). These images can be acquired even while scanning continental United States and full disk images. These high time-resolution images from the GOES-14 imager are being used to prepare for the GOES-R era and its advanced imager. This includes both the imagery and quantitative derived products such as cloud-top cooling. Several animations are included to showcase the rapid change of the many phenomena observed during super rapid scan operations for GOES-R (SRSOR).

  2. Environmental Scanning Activities in Higher Education as Reported at the 1986 Annual Meetings of AAHE, AIR, and SCUP.

    ERIC Educational Resources Information Center

    Morrison, James L.

    Environmental scanning activities in higher education were described in forums at the 1986 annual meetings of the American Association for Higher Education (AAHE), the Association for Institutional Research (AIR), and the Society of College and University Planning (SCUP). The forums were held to determine the extent of environmental scanning…

  3. Ontario primary care reform and quality improvement activities: an environmental scan

    PubMed Central

    2013-01-01

    Background Quality improvement is attracting the attention of the primary health care system as a means by which to achieve higher quality patient care. Ontario, Canada has demonstrated leadership in terms of its improvement in healthcare, but the province lacks a structured framework by which it can consistently evaluate its quality improvement initiatives specific to the primary healthcare system. The intent of this research was to complete an environmental scan and capacity map of quality improvement activities being built in and by the primary healthcare sector (QI-PHC) in Ontario as a first step to developing a coordinated and sustainable framework of primary healthcare for the province. Methods Data were collected between January and July 2011 in collaboration with an advisory group of stakeholder representatives and quality improvement leaders in primary health care. Twenty participants were interviewed by telephone, followed by review of relevant websites and documents identified in the interviews. Data were systematically examined using Framework Analysis augmented by Prior’s approach to document analysis in an iterative process. Results The environmental scan identified many activities (n = 43) designed to strategically build QI-PHC capacity, identify promising QI-PHC practices and outcomes, scale up quality improvement-informed primary healthcare practice changes, and make quality improvement a core organizational strategy in health care delivery, which were grouped into clusters. Cluster 1 was composed of initiatives in the form of on-going programs that deliberately incorporated long-term quality improvement capacity building through province-wide reach. Cluster 2 represented activities that were time-limited (research, pilot, or demonstration projects) with the primary aim of research production. The activities of most primary health care practitioners, managers, stakeholder organizations and researchers involved in this scan demonstrated a

  4. Advance care planning, culture and religion: an environmental scan of Australian-based online resources.

    PubMed

    Pereira-Salgado, Amanda; Mader, Patrick; Boyd, Leanne M

    2017-04-20

    Objectives Culture and religion are important in advance care planning (ACP), yet it is not well understood how this is represented in ACP online resources. The aim of the present study was to identify the availability of Australian-based ACP websites and online informational booklets containing cultural and religious information.Methods An environmental scanning framework was used with a Google search conducted from 30 June 2015 to 5 July 2015. Eligible Australian-based ACP websites and online informational booklets were reviewed by two analysts (APS & PM) for information pertaining to at least one culture or religion. Common characteristics were agreed upon and tabulated with narrative description.Results Seven Australian-based ACP websites were identified with varying degrees of cultural and religious information. Seven Australian-based ACP informational booklets were identified addressing culture or religion, namely of Aboriginal and Torres Strait Islander (n=5), Sikh (n=1) and Italian (n=1) communities. Twenty-one other online resources with cultural and religious information were identified, developed within the context of health and palliative care.Conclusions There is no comprehensive Australian-based ACP website or informational booklet supporting ACP across several cultural and religious contexts. Considering Australia's multicultural and multifaith population, such a resource may be beneficial in increasing awareness and uptake of ACP.What is known about the topic? Health professionals and consumers frequently use the Internet to find information. Non-regulation has resulted in the proliferation of ACP online resources (i.e. ACP websites and online informational booklets). Although this has contributed to raising awareness of ACP, the availability of Australian-based ACP online resources with cultural and religious information is not well known.What does this paper add? This paper is the first to use an environmental scanning methodology to identify

  5. The low-temperature method for study of coniferous tissues in the environmental scanning electron microscope.

    PubMed

    Neděla, Vilém; Tihlaříková, Eva; Hřib, Jiří

    2015-01-01

    The use of non-standard low-temperature conditions in environmental scanning electron microscopy might be promising for the observation of coniferous tissues in their native state. This study is aimed to analyse and evaluate the method based on the principle of low-temperature sample stabilization. We demonstrate that the upper mucous layer is sublimed and a microstructure of the sample surface can be observed with higher resolution at lower gas pressure conditions, thanks to a low-temperature method. An influence of the low-temperature method on sample stability was also studied. The results indicate that high-moisture conditions are not suitable for this method and often cause the collapse of samples. The potential improvement of stability to beam damage has been demonstrated by long-time observation at different operation parameters. We finally show high applicability of the low-temperature method on different types of conifers and Oxalis acetosella. © 2014 Wiley Periodicals, Inc.

  6. Determination of the coalescence temperature of latexes by environmental scanning electron microscopy.

    PubMed

    Gonzalez, Edurne; Tollan, Christopher; Chuvilin, Andrey; Barandiaran, Maria J; Paulis, Maria

    2012-08-01

    A new methodology for quantitative characterization of the coalescence process of waterborne polymer dispersion (latex) particles by environmental scanning electron microscopy (ESEM) is proposed. The experimental setup has been developed to provide reproducible latex monolayer depositions, optimized contrast of the latex particles, and a reliable readout of the sample temperature. Quantification of the coalescence process under dry conditions has been performed by image processing based on evaluation of the image autocorrelation function. As a proof of concept the coalescence of two latexes with known and differing glass transition temperatures has been measured. It has been shown that a reproducibility of better than 1.5 °C can be obtained for the measurement of the coalescence temperature.

  7. Preliminary report: laboratory-induced stain removal as assessed by environmental scanning electron microscopy.

    PubMed

    Habib, C M; Kugel, G; Marcus, A

    1998-01-01

    Environmental scanning electron microscopy (ESEM) was employed to observe stain removal during brushing with Arm & Hammer Dental Care and Crest Regular Toothpaste. ESEM allows serial examinations of the same sample, and does not require a destructive preparative process. Three extracted molars were cleaned, placed into a 96-hour broth culture of Streptococcus mutans, and stain was produced with undiluted chlorhexidine rinse, concentrated coffee and tea for a period of 23 days. After staining, the teeth were examined by ESEM, then brushed using a toothbrushing machine. Imaging was repeated after 5, 10, 15 and 30 seconds of brushing. As seen with ESEM, the Arm & Hammer product had different effects than those from the distilled water control, suggesting something other than that expected from abrasive and mechanical forces alone. There were also differences from the Crest dentifrice removal on this single sample, suggesting a possible difference between the two products. Further studies are needed to confirm and explain these effects.

  8. Gold nanoparticle uptake in whole cells in liquid examined by environmental scanning electron microscopy.

    PubMed

    Peckys, Diana B; de Jonge, Niels

    2014-02-01

    The size of gold nanoparticles (AuNPs) can influence various aspects of their cellular uptake. Light microscopy is not capable of resolving most AuNPs, while electron microscopy (EM) is not practically capable of acquiring the necessary statistical data from many cells and the results may suffer from various artifacts. Here, we demonstrate the use of a fast EM method for obtaining high-resolution data from a much larger population of cells than is usually feasible with conventional EM. A549 (human lung carcinoma) cells were subjected to uptake protocols with 10, 15, or 30 nm diameter AuNPs with adsorbed serum proteins. After 20 min, 24 h, or 45 h, the cells were fixed and imaged in whole in a thin layer of liquid water with environmental scanning electron microscopy equipped with a scanning transmission electron microscopy detector. The fast preparation and imaging of 145 whole cells in liquid allowed collection of nanoscale data within an exceptionally small amount of time of ~80 h. Analysis of 1,041 AuNP-filled vesicles showed that the long-term AuNP storing lysosomes increased their average size by 80 nm when AuNPs with 30 nm diameter were uptaken, compared to lysosomes of cells incubated with AuNPs of 10 and 15 nm diameter.

  9. Copper thick film sintering studies in an environmental scanning electron microscope.

    PubMed

    Link, L F; Gerristead, W R; Tamhankar, S

    1993-08-01

    The significance of the ElectroScan environmental scanning electron microscope (ESEM) as a processing tool for studying dynamic morphological changes under controlled temperature/atmosphere conditions was evaluated. The ability to observe dynamic processes in situ, which cannot be achieved by other means, is critical to understanding microstructural formation. Processing of printed copper thick films on ceramics was used as a test case, wherein morphological changes associated with the steps of organic binder removal and sintering of copper particles were observed/examined in real time. Good agreement was seen between microstructures obtained in the ESM and those achieved in a belt furnace when similar process variables were used. When processed in atmospheres which were proven to induce sintering in a conventional belt furnace, sintering was evident in both cases, and the microstructural changes were documented on video-tapes in real time. Determination of critical event temperatures was achieved--that is, binder burnout occurring between 270 degrees and 350 degrees C, onset of oxidation at 520 degrees C, and sintering starting at 770 degrees C. It was thus verified that the microstructural changes during the copper thick film sintering process can be observed in situ using an ESEM.

  10. Microfluidic device for a rapid immobilization of zebrafish larvae in environmental scanning electron microscopy.

    PubMed

    Akagi, Jin; Zhu, Feng; Skommer, Joanna; Hall, Chris J; Crosier, Philip S; Cialkowski, Michal; Wlodkowic, Donald

    2015-03-01

    Small vertebrate model organisms have recently gained popularity as attractive experimental models that enhance our understanding of human tissue and organ development. Despite a large body of evidence using optical spectroscopy for the characterization of small model organism on chip-based devices, no attempts have been so far made to interface microfabricated technologies with environmental scanning electron microscopy (ESEM). Conventional scanning electron microscopy requires high vacuum environments and biological samples must be, therefore, submitted to many preparative procedures to dehydrate, fix, and subsequently stain the sample with gold-palladium deposition. This process is inherently low-throughput and can introduce many analytical artifacts. This work describes a proof-of-concept microfluidic chip-based system for immobilizing zebrafish larvae for ESEM imaging that is performed in a gaseous atmosphere, under low vacuum mode and without any need for sample staining protocols. The microfabricated technology provides a user-friendly and simple interface to perform ESEM imaging on zebrafish larvae. Presented lab-on-a-chip device was fabricated using a high-speed infrared laser micromachining in a biocompatible poly(methyl methacrylate) thermoplastic. It consisted of a reservoir with multiple semispherical microwells designed to hold the yolk of dechorionated zebrafish larvae. Immobilization of the larvae was achieved by a gentle suction generated during blotting of the medium. Trapping region allowed for multiple specimens to be conveniently positioned on the chip-based device within few minutes for ESEM imaging.

  11. In-Situ Imaging of Langmuir Films using Environmental Scanning Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Miller, Aline

    2002-03-01

    Environmental scanning electron microscopy (ESEM) has been applied to image the organization of spread films at the air-water interface directly. This recent extension of conventional scanning electron microscopy permits the resolution of electron microscopy to be applied to insulated and hydrated samples maintained in their natural state. We demonstrate the great potential of this technique by in-situ imaging of both synthetic and natural polymer spread films at the air-water interface. A brief synopsis of the background to ESEM will be given followed by a discussion of the pertinent experimental conditions for the study of Langmuir layers. Experimental results for two systems will be presented. Firstly results for a nylon 6 6 polymer film will be given and discussed in relation to external reflection FTIR studies and those using the more conventional analytical techniques of surface pressure isotherms and optical microscopy. Secondly the kinetics of the interaction of a cationic intercalator amphiphile with double stranded DNA at the air-water interface will be presented and the structure of the densely packed two-dimensional arrays formed will be discussed.

  12. Environmental scanning electron microscopy analysis of Proteus mirabilis biofilms grown on chitin and stainless steel.

    PubMed

    Fernández-Delgado, Milagro; Duque, Zoilabet; Rojas, Héctor; Suárez, Paula; Contreras, Monica; García-Amado, María A; Alciaturi, Carlos

    Proteus mirabilis is a human pathogen able to form biofilms on the surface of urinary catheters. Little is known about P. mirabilis biofilms on natural or industrial surfaces and the potential consequences for these settings. The main aim of this work was to assess and compare the adhesion and biofilm formation of P. mirabilis strains from different origins on chitin and stainless steel surfaces within 4 to 96 h. Using environmental scanning electron microscopy, the biofilms of a clinical strain grown on chitin at 4 h showed greater adhesion, aggregation, thickness, and extracellular matrix production than those grown on stainless steel, whereas biofilms of an environmental strain had less aggregation on both surfaces. Biofilms of both P. mirabilis strains developed different structures on chitin, such as pillars, mushrooms, channels, and crystalline-like precipitates between 24 and 96 h, in contrast with flat-layer biofilms produced on stainless steel. Significant differences (p < 0.05) were found in the frequency of pillars and channels. Images of transmission electron microscopy demonstrated abundant fimbriae in 100 % of cells from both strains, which could be related to surface adherence and biofilm formation. This represents the first study of P. mirabilis showing adhesion, biofilm formation, and development of different structures on surfaces found outside the human host.

  13. Toward quantitative electrochemical measurements on the nanoscale by scanning probe microscopy: environmental and current spreading effects.

    PubMed

    Arruda, Thomas M; Kumar, Amit; Jesse, Stephen; Veith, Gabriel M; Tselev, Alexander; Baddorf, Arthur P; Balke, Nina; Kalinin, Sergei V

    2013-09-24

    The application of electric bias across tip-surface junctions in scanning probe microscopy can readily induce surface and bulk electrochemical processes that can be further detected though changes in surface topography, Faradaic or conductive currents, or electromechanical strain responses. However, the basic factors controlling tip-induced electrochemical processes, including the relationship between applied tip bias and the thermodynamics of local processes, remains largely unexplored. Using the model Li-ion reduction reaction on the surface in Li-ion conducting glass ceramic, we explore the factors controlling Li-metal formation and find surprisingly strong effects of atmosphere and back electrode composition on the process. We find that reaction processes are highly dependent on the nature of the counter electrode and environmental conditions. Using a nondepleting Li counter electrode, Li particles could grow significantly larger and faster than a depleting counter electrode. Significant Li ion depletion leads to the inability for further Li reduction. Time studies suggest that Li diffusion replenishes the vacant sites after ∼12 h. These studies suggest the feasibility of SPM-based quantitative electrochemical studies under proper environmental controls, extending the concepts of ultramicroelectrodes to the single-digit nanometer scale.

  14. Environmental scanning as a moderator of strategy-performance relationships: an empirical analysis of physical therapy facilities.

    PubMed

    Davis, Mark A; Miles, Grant; McDowell, William C

    2008-05-01

    To date, strategic management research in health care is largely confined to the acute care sector of the industry. This research examines the linkages among environmental scanning, competitive strategy and performance in physical therapy facilities. Nontrivial differences between acute and subacute care firms suggest the role of environmental scanning may change in non-acute care settings. Consistent with previous research, these results indicate that the frequency of internal and external scanning is related to the strategic orientation of physical therapy facilities. Contrary to the expectations, broader scope of scanning is positively related to an increasing market-focused and increasing efficiency strategic orientation. A key objective of the research is to test the impact of strategy/scanning alignment on facility performance. These findings support predictions on the moderating role of scanning activities in the strategy-performance relationship. However, a paradoxical pattern of results has possible implications for clinician managers in subacute care settings as well as the interpretation of scanning activities.

  15. The surface topography of the choroid plexus. Environmental, low and high vacuum scanning electron microscopy.

    PubMed

    Mestres, Pedro; Pütz, Norbert; Garcia Gómez de Las Heras, Soledad; García Poblete, Eduardo; Morguet, Andrea; Laue, Michael

    2011-05-01

    Environmental scanning electron microscopy (ESEM) allows the examination of hydrated and dried specimens without a conductive metal coating which could be advantageous in the imaging of biological and medical objects. The aim of this study was to assess the performance and benefits of wet-mode and low vacuum ESEM in comparison to high vacuum scanning electron microscopy (SEM) using the choroid plexus of chicken embryos as a model, an organ of the brain involved in the formation of cerebrospinal fluid in vertebrates. Specimens were fixed with or without heavy metals and examined directly or after critical point drying with or without metal coating. For wet mode ESEM freshly excised specimens without any pre-treatment were also examined. Conventional high vacuum SEM revealed the characteristic morphology of the choroid plexus cells at a high resolution and served as reference. With low vacuum ESEM of dried but uncoated samples the structure appeared well preserved but charging was a problem. It could be reduced by a short beam dwell time and averaging of images or by using the backscattered electron detector instead of the gaseous secondary electron detector. However, resolution was lower than with conventional SEM. Wet mode imaging was only possible with tissue that had been stabilized by fixation. Not all surface details (e.g. microvilli) could be visualized and other structures, like the cilia, were deformed. In summary, ESEM is an additional option for the imaging of bio-medical samples but it is problematic with regard to resolution and sample stability during imaging. Copyright © 2011 Elsevier GmbH. All rights reserved.

  16. Environmental scanning electron microscopy study of the interaction of carbon nanotubes with fluids

    NASA Astrophysics Data System (ADS)

    Rossi, Maria Pia

    The behavior of fluids at the nanoscale is currently of interest, as nanotechnology promises tools for the precise delivery and analysis of minute volumes of liquids. Because of their reported properties, ease of manipulation and hollow cavity, carbon nanotubes have attracted attention for fluidic delivery. Thus far, experimental studies on wetting of carbon nanotubes have been limited, and other work revolves around theoretical modeling. Consequently, there is a considerable lack of experimental data on the subject. In this work, environmental scanning electron microscopy was employed for visualization of the interaction of carbon nanotubes with fluids such as water, liquid crystals, and biological solutions. Carbon nanotubes of diverse surface structure and chemistry were evaluated, and hydrophobic and hydrophilic behavior was observed. Nanotubes made by catalytic chemical vapor deposition showed highly hydrophobic behavior by the formation of spherical water droplets on nanotube agglomerates. This behavior was caused by roughness of the agglomerates as well as pinning of the droplets on defects and functional groups along the walls of the nanotubes. On highly graphitic carbon nanotube agglomerates, no droplet formation was observed due to the lack of defects and terminations on the surface. Formation of "barrel" and "clam-shell" shaped droplets on individual nanotubes was also observed. Capillary condensation inside carbon nanotubes made by non-catalytic chemical vapor deposition was also observed in the environmental scanning electron microscope. Condensation was marked by the formation of a thin film of water on the inner walls of the nanotubes, followed by growth of a meniscus of low contact angle, indicating the hydrophilic nature of the nanotubes. Spontaneous elastic deformation of the nanotubes was observed upon the formation of the film due to surface tension effects. By annealing, the carbon nanotubes were graphitized, and highly hydrophobic behavior was

  17. Shape of allied health: an environmental scan of 27 allied health professions in Victoria.

    PubMed

    Nancarrow, Susan A; Young, Gretchen; O'Callaghan, Katy; Jenkins, Mathew; Philip, Kathleen; Barlow, Kegan

    2016-08-11

    Objective In 2015, the Victorian Department of Health and Human Services commissioned the Victorian Allied Health Workforce Research Program to provide data on allied health professions in the Victorian public, private and not-for-profit sectors. Herein we present a snapshot of the demographic profiles and distribution of these professions in Victoria and discuss the workforce implications.Methods The program commenced with an environmental scan of 27 allied health professions in Victoria. This substantial scoping exercise identified existing data, resources and contexts for each profession to guide future data collection and research. Each environmental scan reviewed existing data relating to the 27 professions, augmented by an online questionnaire sent to the professional bodies representing each discipline.Results Workforce data were patchy but, based on the evidence available, the allied health professions in Victoria vary greatly in size (ranging from just 17 child life therapists to 6288 psychologists), are predominantly female (83% of professions are more than 50% female) and half the professions report that 30% of their workforce is aged under 30 years. New training programs have increased workforce inflows to many professions, but there is little understanding of attrition rates. Professions reported a lack of senior positions in the public sector and a concomitant lack of senior specialised staff available to support more junior staff. Increasing numbers of allied health graduates are being employed directly in private practice because of a lack of growth in new positions in the public sector and changing funding models. Smaller professions reported that their members are more likely to be professionally isolated within an allied health team or larger organisations. Uneven rural-urban workforce distribution was evident across most professions.Conclusions Workforce planning for allied health is extremely complex because of the lack of data, fragmented

  18. Structure and characteristics of community-based multidisciplinary wound care teams in Ontario: an environmental scan.

    PubMed

    Abrahamyan, Lusine; Wong, Josephine; Pham, Ba'; Trubiani, Gina; Carcone, Steven; Mitsakakis, Nicholas; Rosen, Laura; Rac, Valeria E; Krahn, Murray

    2015-01-01

    Multidisciplinary team approach is an essential component of evidence-based wound management in the community. The objective of this study was to identify and describe community-based multidisciplinary wound care teams in Ontario. For the study, a working definition of a multidisciplinary wound care team was developed, and a two-phase field evaluation was conducted. In phase I, a systematic survey with three search strategies (environmental scan) was conducted to identify all multidisciplinary wound care teams in Ontario. In phase II, the team leads were surveyed about the service models of the teams. We identified 49 wound care teams in Ontario. The highest ratio of Ontario seniors to wound team within each Ontario health planning region was 82,358:1; the lowest ratio was 14,151:1. Forty-four teams (90%) participated in the survey. The majority of teams existed for at least 5 years, were established as hospital outpatient clinics, and served patients with chronic wounds. Teams were heterogeneous in on-site capacity of specialized diagnostic testing and wound treatment, team size, and patient volume. Seventy-seven percent of teams had members from three or more disciplines. Several teams lacked essential disciplines. More research is needed to identify optimal service models leading to improved patient outcomes. © 2014 by the Wound Healing Society.

  19. Contact angle analysis on polymethylmethacrylate and commercial wax by using an environmental scanning electron microscope.

    PubMed

    Brugnara, Marco; Della Volpe, Claudio; Siboni, Stefano; Zeni, Dario

    2006-01-01

    The environmental scanning electron microscope (ESEM) represents one of the most exciting breakthroughs in electron microscopy since the invention of the electron microscope. Its ability to observe uncoated and hydrated samples enhances the possibility for investigating the wettability of surfaces at a microscopic level; by varying the relative vapour pressure or the temperature inside the chamber, it is possible to condense water drops on a micron scale. A large problem in measuring contact angles by ESEM is that the observation angle is not parallel or perpendicular to the surface; thus, the study of the droplets profile using the common algorithms such as spherical approximation or axisymmetric drop shape analysis (ADSA) is not possible, because only a spherical cap shape is commonly observed. In this paper we provide a useful mathematical model to calculate the real contact angle from the initial images. Initially, some simulated spherical caps with different contact and observation angles were created by an appropriate graphic package in order to test the mathematical model. Some real drops obtained by ESEM on wax and polymethylmethacrylate (PMMA) were then studied and the results compared with contact angles measured by common methods on the same materials.

  20. An environmental scan of policies in support of chronic disease self-management in Canada.

    PubMed

    Liddy, C; Mill, K

    2014-02-01

    The evidence supporting chronic disease self-management warrants further attention. Our aim was to identify existing policies, strategies and frameworks that support self-management initiatives. This descriptive study was conducted as an environmental scan, consisting of an Internet search of government and other publicly available websites, and interviews with jurisdictional representatives identified through the Health Council of Canada and academic networking. We interviewed 16 representatives from all provinces and territories in Canada and found 30 publicly available and relevant provincial and national documents. Most provinces and territories have policies that incorporate aspects of chronic disease self-management. Alberta and British Columbia have the most detailed policies. Both feature primary care prominently and are not disease specific. Both also have provincial level implementation of chronic disease self-management programming. Canada's northern territories all lacked specific policies supporting chronic disease self-management despite a significant burden of disease. Engaging patients in self-management of their chronic diseases is important and effective. Although most provinces and territories have policies that incorporate aspects of chronic disease self-management, they were often embedded within other initiatives and/or policy documents framed around specific diseases or populations. This approach could limit the potential reach and effect of self-management.

  1. In situ study of single-walled carbon nanotube growth in an environmental scanning electron microscope.

    PubMed

    Mehedi, H-A; Ravaux, J; Tahir, S; Podor, R; Jourdain, V

    2016-12-16

    Monitoring individual single-walled carbon nanotubes (SWCNTs) during their growth is a highly sought-after goal in view of understanding the processes involved in the nucleation, elongation and termination which ultimately control the diameter and chiral selectivity. Here, we report on the first truly in situ observations of SWCNT growth in an environmental scanning electron microscope (ESEM). The CNT growth from lithographically patterned catalysts was investigated as a function of the catalyst type (Fe, Co or Ni), temperature, type of precursor (ethanol or acetylene), gas phase composition and pressure, and pretreatment conditions, and we report on the most appropriate conditions for SWCNT growth in ESEM conditions. We show that this approach allows the observation at the submicron scale of the different steps of the nanotube synthesis including the catalyst reduction, the growth and percolation of the nanotube network, and the deposition of individual nanotubes grown in the gas phase on the substrate. Despite these obvious advantages, we identified a few limitations which will need to be tackled for fully taking advantage of the approach, for instance for monitoring the growth of individual SWCNTs by ESEM, including the short lifetime of the catalyst nanoparticles, the preference for kite growth (by opposition to surface growth) and the influence of the electron beam on the nanotube growth.

  2. Swelling-shrinkage measurements of bentonite using coupled environmental scanning electron microscopy and digital image analysis.

    PubMed

    Montes-H, G

    2005-04-01

    The swelling clays have been proposed as engineered barriers in geological disposal systems for waste because these materials are assumed to build a better impermeable zone around wastes by swelling. However, the swelling potential of soils is also considered a prevalent cause of damage to buildings and constructions. For these reasons, it is fundamental to investigate the physicochemical and mechanical behavior of swelling clays. In the current study, the swelling-shrinkage potential (aggregates scale) was estimated using an environmental scanning electron microscope (ESEM) coupled with a digital image analysis (DIA) program (Visilog). In fact, the isolated aggregates of raw and cation-exchanged bentonite were directly observed at different relative humidities in an ESEM chamber. Then the "Visilog" software was used to estimate the percent augmentation of the aggregate surface as a function of time and as a function of relative humidity. This estimation allows for the calculation of the swelling-shrinkage potential (%) of bentonite. Finally, a kinetic model of first order was tested to fit the kinetic experimental data of swelling-shrinkage potential. The results show that ESEM-DIA coupling can be a powerful method of estimating the swelling-shrinkage potential of expansive clays. In addition, the exponential models fit well with the kinetic experimental data.

  3. An optimized methodology to analyze biopolymer capsules by environmental scanning electron microscopy.

    PubMed

    Conforto, Egle; Joguet, Nicolas; Buisson, Pierre; Vendeville, Jean-Eudes; Chaigneau, Carine; Maugard, Thierry

    2015-02-01

    The aim of this paper is to describe an optimized methodology to study the surface characteristics and internal structure of biopolymer capsules using scanning electron microscopy (SEM) in environmental mode. The main advantage of this methodology is that no preparation is required and, significantly, no metallic coverage is deposited on the surface of the specimen, thus preserving the original capsule shape and its surface morphology. This avoids introducing preparation artefacts which could modify the capsule surface and mask information concerning important feature like porosities or roughness. Using this method gelatin and mainly fatty coatings, difficult to be analyzed by standard SEM technique, unambiguously show fine details of their surface morphology without damage. Furthermore, chemical contrast is preserved in backscattered electron images of unprepared samples, allowing visualizing the internal organization of the capsule, the quality of the envelope, etc... This study provides pointers on how to obtain optimal conditions for the analysis of biological or sensitive material, as this is not always studied using appropriate techniques. A reliable evaluation of the parameters used in capsule elaboration for research and industrial applications, as well as that of capsule functionality is provided by this methodology, which is essential for the technological progress in this domain.

  4. In situ study of single-walled carbon nanotube growth in an environmental scanning electron microscope

    NASA Astrophysics Data System (ADS)

    Mehedi, H.-A.; Ravaux, J.; Tahir, S.; Podor, R.; Jourdain, V.

    2016-12-01

    Monitoring individual single-walled carbon nanotubes (SWCNTs) during their growth is a highly sought-after goal in view of understanding the processes involved in the nucleation, elongation and termination which ultimately control the diameter and chiral selectivity. Here, we report on the first truly in situ observations of SWCNT growth in an environmental scanning electron microscope (ESEM). The CNT growth from lithographically patterned catalysts was investigated as a function of the catalyst type (Fe, Co or Ni), temperature, type of precursor (ethanol or acetylene), gas phase composition and pressure, and pretreatment conditions, and we report on the most appropriate conditions for SWCNT growth in ESEM conditions. We show that this approach allows the observation at the submicron scale of the different steps of the nanotube synthesis including the catalyst reduction, the growth and percolation of the nanotube network, and the deposition of individual nanotubes grown in the gas phase on the substrate. Despite these obvious advantages, we identified a few limitations which will need to be tackled for fully taking advantage of the approach, for instance for monitoring the growth of individual SWCNTs by ESEM, including the short lifetime of the catalyst nanoparticles, the preference for kite growth (by opposition to surface growth) and the influence of the electron beam on the nanotube growth.

  5. Experimental evaluation of environmental scanning electron microscopes at high chamber pressure.

    PubMed

    Fitzek, H; Schroettner, H; Wagner, J; Hofer, F; Rattenberger, J

    2015-11-01

    In environmental scanning electron microscopy (ESEM) high pressure applications have become increasingly important. Wet or biological samples can be investigated without time-consuming sample preparation and potential artefacts from this preparation can be neglected. Unfortunately, the signal-to-noise ratio strongly decreases with increasing chamber pressure. To evaluate the high pressure performance of ESEM and to compare different electron microscopes, information about spatial resolution and detector type is not enough. On the one hand, the scattering of the primary electron beam increases, which vanishes the contrast in images; and on the other hand, the secondary electrons (SE) signal amplification decreases. The stagnation gas thickness (effective distance the beam has to travel through the imaging gas) as well as the SE detection system depend on the microscope and for a complete and serious evaluation of an ESEM or low vacuum SEM it is necessary to specify these two parameters. A method is presented to determine the fraction of scattered and unscattered electrons and to calculate the stagnation gas thickness (θ). To evaluate the high pressure performance of the SE detection system, a method is presented that allows for an analysis of a single image and the calculation of the signal-to-noise ratio of this image. All investigations are performed on an FEI ESEM Quanta 600 (field emission gun) and an FEI ESEM Quanta 200 (thermionic gun). These methods and measurements should represent opportunities for evaluating the high pressure performance of an ESEM.

  6. Engineering and Characterization of Collagen Networks Using Wet Atomic Force Microscopy and Environmental Scanning Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Osborn, Jenna; Coffey, Tonya; Conrad, Brad; Burris, Jennifer; Hester, Brooke

    2014-03-01

    Collagen is an abundant protein and its monomers covalently crosslink to form fibrils which form fibers which contribute to forming macrostructures like tendon or bone. While the contribution is well understood at the macroscopic level, it is not well known at the fibril level. We wish to study the mechanical properties of collagen for networks of collagen fibers that vary in size and density. We present here a method to synthesize collagen networks from monomers and that allows us to vary the density of the networks. By using biotynilated collagen and a surface that is functionalized with avidin, we generate two-dimensional collagen networks across the surface of a silicon wafer. During network synthesis, the incubation time is varied from 30 minutes to 3 hours or temperature is varied from 25°C to 45°C. The two-dimensional collagen network created in the process is characterized using environmental atomic force microscopy (AFM) and scanning electron microscopy (SEM). The network density is measured by the number of strands in one frame using SPIP software. We expect that at body temperature (37°C) and with longer incubation times, the network density should increase.

  7. Using environmental scanning electron microscopy to determine the hygroscopic properties of agricultural aerosols

    NASA Astrophysics Data System (ADS)

    Hiranuma, Naruki; Brooks, Sarah D.; Auvermann, Brent W.; Littleton, Rick

    A field study at a cattle feedlot in the Texas Panhandle was conducted to characterize the hygroscopic, morphological, and chemical properties of agricultural aerosols and to identify possible correlations between these properties. To explore the hygroscopic nature of the agricultural particles, we have collected size-resolved aerosol samples using a cascade impactor system and have used an environmental scanning electron microscope (ESEM) to determine the water uptake by individual particles in those samples as a function of relative humidity (RH). In addition, complementary determination of the elemental composition of single particles was performed using energy dispersive X-ray spectroscopy (EDS). Our results indicate that most of the agricultural particles do not take up significant amounts of water when exposed to up to 96% RH. However, a small fraction of particles in the coarse mode deliquesced at approximately 75% RH and reached twice their original sizes by 96% RH. The observed changes in particle size with increased RH may significantly impact total aerosol extinction, visibility, and human health.

  8. The current state of electronic consultation and electronic referral systems in Canada: an environmental scan.

    PubMed

    Liddy, Clare; Hogel, Matthew; Blazkho, Valerie; Keely, Erin

    2015-01-01

    Access to specialist care is a point of concern for patients, primary care providers, and specialists in Canada. Innovative e-health platforms such as electronic consultation (eConsultation) and referral (eReferral) can improve access to specialist care. These systems allow physicians to communicate asynchronously and could reduce the number of unnecessary referrals that clog wait lists, provide a record of the patient's journey through the referral system, and lead to more efficient visits. Little is known about the current state of eConsultation and eReferral in Canada. The purpose of this work was to identify current systems and gain insight into the design and implementation process of existing systems. An environmental scan approach was used, consisting of a systematic and grey literature review, and targeted semi-structured key informant interviews. Only three eConsultation/eReferral systems are currently in operation in Canada. Four themes emerged from the interviews: eReferral is an end goal for those provinces without an active eReferral system, re-organization of the referral process is a necessity prior to automation, engaging the end-user is essential, and technological incompatibilities are major impediments to progress. Despite the acknowledged need to improve the referral system and increase government spending on health information technology, eConsultation and eReferral systems remain scarce as Canada lags behind the rest of the developed world.

  9. Intelligent Agent Appropriation in the Tracking Phase of an Environmental Scanning Process: A Case Study of a French Trade Union

    ERIC Educational Resources Information Center

    Lafaye, Christophe

    2009-01-01

    Introduction: The rapid growth of the Internet has modified the boundaries of information acquisition (tracking) in environmental scanning. Despite the numerous advantages of this new medium, information overload is an enormous problem for Internet scanners. In order to help them, intelligent agents (i.e., autonomous, automated software agents…

  10. From Reactionary to Responsive: Applying the Internal Environmental Scan Protocol to Lifelong Learning Strategic Planning and Operational Model Selection

    ERIC Educational Resources Information Center

    Downing, David L.

    2009-01-01

    This study describes and implements a necessary preliminary strategic planning procedure, the Internal Environmental Scanning (IES), and discusses its relevance to strategic planning and university-sponsored lifelong learning program model selection. Employing a qualitative research methodology, a proposed lifelong learning-centric IES process…

  11. An environmental scan of advance care planning decision AIDS for patients undergoing major surgery: a study protocol.

    PubMed

    Aslakson, Rebecca A; Schuster, Anne L R; Miller, Judith; Weiss, Matthew; Volandes, Angelo E; Bridges, John F P

    2014-01-01

    Patients who undergo major surgery are at risk for perioperative morbidity and mortality. It would be appropriate to initiate advance care planning with patients prior to surgery, but surgeons may experience difficulty initiating such conversations. Rather than focus on changing clinician behavior, advance care planning decision aids can be an innovative vehicle to motivate advance care planning among surgical patients and their families. The purpose of this paper is to describe a study protocol for conducting an environmental scan concerning advance care planning decision aids that may be relevant to patients undergoing high-risk surgery. This study will gather information from written or verbal data sources that incorporate professional and lay perspectives: a systematic review, a grey literature review, key informant interviews, and patient and family engagement. It is envisioned that this study will generate three outcomes: a synthesis of current evidence, a summary of gaps in knowledge, and a taxonomy of existing advance care planning decision aids. This environmental scan will demonstrate principles of patient-centered outcomes research, and it will exemplify a pioneering approach for reviewing complex interventions. Anticipated limitations are that information will be gathered from a small sample of patients and families, and that potentially relevant information could also be missing from the environmental scan due to the inclusion/exclusion criteria. Outcomes from the environmental scan will inform future patient-centered research to develop and evaluate a new decision aid.

  12. From Reactionary to Responsive: Applying the Internal Environmental Scan Protocol to Lifelong Learning Strategic Planning and Operational Model Selection

    ERIC Educational Resources Information Center

    Downing, David L.

    2009-01-01

    This study describes and implements a necessary preliminary strategic planning procedure, the Internal Environmental Scanning (IES), and discusses its relevance to strategic planning and university-sponsored lifelong learning program model selection. Employing a qualitative research methodology, a proposed lifelong learning-centric IES process…

  13. Use of environmental scanning electron microscopy to evaluate dental stain removal.

    PubMed

    Zammitti, S; Habib, C; Kugel, G

    1997-01-01

    The purpose of the study was to assess the usefulness of environmental scanning electron microscopy (ESEM) to evaluate stain removal from extracted teeth. The ESEM differs from conventional SEM in that no sample preparation is needed, eliminating artifactual changes. Furthermore, the same sample can be viewed on multiple occasions, allowing "before" and "after" pictures of the same tooth. As a model stain removal device, we tested the Sonicare sonic toothbrush, which has previously been shown to remove dental stain in vivo. Twelve freshly extracted teeth with extrinsic coffee, tea or tobacco stain were obtained for the study. Nine of these had heavy stain (stain covering more than one-third buccal or lingual surface) and were used without further modification. Three teeth were treated in vitro with chlorhexidine and a mixture of coffee and tea to enhance staining. All teeth were examined by ESEM at three times: prior to brushing, after 15-30 seconds of brushing, and after 60-80 seconds of brushing. Light microscopy and 35 mm photography was also done to correlate the ultrastructural changes with those visible at low magnification. Water, mouthwash and 30% slurry of toothpaste were used as fluid vehicles during brushing, but little difference in stain removal was noted among these three fluids. Approximately half the stain was removed within 15-30 seconds, and most visible stain was removed in 60-80 seconds of brushing. Pits and crevices of tooth enamel that were smaller than the bristle diameter, and thus would be inaccessible to abrasive cleaning by direct bristle contact, were generally found to be stain-free. These findings confirm previous reports of the stain removal effectiveness of the Sonicare, and demonstrate the usefulness of ESEM for stain removal studies.

  14. Assessing access for prospective adoptive parents living with HIV: an environmental scan of Ontario's adoption agencies.

    PubMed

    Underhill, Angela A; Kennedy, V Logan; Lewis, Johanna; Ross, Lori E; Loutfy, Mona

    2016-10-01

    Work has been underway to increase the availability of parenting options for people living with and affected by HIV. One option, adoption, has not yet been explored in the literature. The study aimed to gain a better understanding of the potential of adoption for individuals/couples living with HIV in Ontario, and to assess potential structural barriers or facilitators that may impact their experience navigating the adoption system by conducting an environmental scan of adoption service providers in Ontario. A list of adoption service providers was compiled using the Ontario government's website. Information relevant to the study's measures was collected using service providers' websites. Service providers without websites, or with websites that did not address all of the research measures, were contacted via telephone to complete a structured interview. Online data extraction was possible for 2 and telephone surveys were completed with 75 adoption service providers (total n = 77). Most service providers reported that HIV status is not an exclusion criterion for prospective parents (64%). However, more than one-fifth of the participants acknowledged they were not sure if people with HIV were eligible to adopt. Domestic service providers were the only providers who did not report knowledge of restrictions due to HIV status. Private domestic adoption presented social barriers as birth parent(s) of a child can access health records of a prospective parent and base their selection of an adoptive parent based on health status. Adoption practitioners and licensees involved in international adoptions reported the most structural barriers for prospective parent(s) living with HIV, attributed to the regulations established by the host country of the child(ren) eligible for adoption. Although international adoptions may present insurmountable barriers for individuals living with HIV, public and private domestic adoption appears to be a viable option.

  15. Specialized multi-disciplinary heart failure clinics in Ontario, Canada: an environmental scan

    PubMed Central

    2012-01-01

    Background Multi-disciplinary heart failure (HF) clinics have been shown to improve outcomes for HF patients in randomized clinical trials. However, it is unclear how widely available specialized HF clinics are in Ontario. Also, the service models of current clinics have not been described. It is therefore uncertain whether the efficacy of HF clinics in trials is generalizable to the HF clinics currently operating in the province. Methods As part of a comprehensive evaluation of HF clinics in Ontario, we performed an environmental scan to identify all HF clinics operating in 2010. A semi-structured interview was conducted to understand the scope of practice. The intensity and complexity of care offered were quantified through the use of a validated instrument, and clinics were categorized as high, medium or low intensity clinics. Results We identified 34 clinics with 143 HF physicians. We found substantial regional disparity in access to care across the province. The majority of HF physicians were cardiologists (81%), with 81% of the clinics physically based in hospitals, of which 26% were academic centers. There was a substantial range in the complexity of services offered, most notably in the intensity of education and medication management services offered. All the clinics focused on ambulatory care, with only one having an in-patient focus. None of the HF clinics had a home-based component to care. Conclusions Multiple HF clinics are currently operating in Ontario with a wide spectrum of care models. Further work is necessary to understand which components lead to improved patient outcomes. PMID:22863276

  16. National, State, and Local Trends: Environmental Scan of Trends and Key Issues Affecting Planning.

    ERIC Educational Resources Information Center

    Kangas, Jon; Budros, Kathleen; Yoshioka, Joyce

    This document is a collection of one-page summaries, or "Trends Newsletters" (Numbers 50, 54-7, 59-60, 67-71, and 73-91), that analyze the national, state, and local trends affecting planning for the San Jose/Evergreen Community College District in California. The document is divided into two sections: External Scan and Internal Scan.…

  17. Horizon scanning for environmental foresight: a review of issues and approaches

    Treesearch

    David N. Bengston

    2013-01-01

    Natural resource management organizations carry out a range of activities to examine possible future conditions and trends as part of their planning process, but the distinct approach of formal horizon scanning is often a missing component of strategic thinking and strategy development in these organizations. Horizon scanning is a process for finding and interpreting...

  18. Worldwide Emerging Environmental Issues Affecting the U.S. Military. Summarizing Environmental Security Monthly Scanning. July 2008 - June 2009

    DTIC Science & Technology

    2009-06-01

    16 A Preventing or repairing military damage to the environment B Preventing or responding to environmentally caused conflicts C Protecting...to implement current legal agreements and make new more-powerful legal instruments are being strengthened. As a result, environmental damages that... damage to the environment, • preventing or responding to environmentally caused conflicts, and • protecting the environment due to its inherent moral

  19. Focusing on Environmental Biofilms With Variable-Pressure Scanning Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Joubert, L.; Wolfaardt, G. M.; Du Plessis, K.

    2006-12-01

    Since the term biofilm has been coined almost 30 years ago, visualization has formed an integral part of investigations on microbial attachment. Electron microscopic (EM) biofilm studies, however, have been limited by the hydrated extracellular matrix which loses structural integrity with conventional preparative techniques, and under required high-vacuum conditions, resulting in a loss of information on spatial relationships and distribution of biofilm microbes. Recent advances in EM technology enable the application of Variable Pressure Scanning Electron Microscopy (VP SEM) to biofilms, allowing low vacuum and hydrated chamber atmosphere during visualization. Environmental biofilm samples can be viewed in situ, unfixed and fully hydrated, with application of gold-sputter-coating only, to increase image resolution. As the impact of microbial biofilms can be both hazardous and beneficial to man and his environment, recognition of biofilms as a natural form of microbial existence is needed to fully assess the potential role of microbial communities on technology. The integration of multiple techniques to elucidate biofilm processes has become imperative for unraveling complex phenotypic adaptations of this microbial lifestyle. We applied VP SEM as integrative technique with traditional and novel analytical techniques to (1)localize lignocellulosic microbial consortia applied for producing alternative bio-energy sources in the mining wastewater industry, (2) characterize and visualize wetland microbial communities in the treatment of winery wastewater, and (3)determine the impact of recombinant technology on yeast biofilm behavior. Visualization of microbial attachment to a lignocellulose substrate, and degradation of exposed plant tissue, gave insight into fiber degradation and volatile fatty acid production for biological sulphate removal from mining wastewater. Also, the 3D-architecture of complex biofilms developing in constructed wetlands was correlated with

  20. Elemental line scanning of an increment core using EDXRF: from fundamental research to environmental forensics applications

    Treesearch

    Kevin T. Smith; Jean Christophe Balouet; Gil Oudijk

    2008-01-01

    Environmental forensics seeks to determine the responsible parties for contamination from leaks or spills of petroleum or other toxic products. Dendrochemistry contributes to environmental forensics at the intersection of analytical chemistry, tree biology, and environmental responsibility. To be useful, dendrochemistry requires the rigorous application of analytical...

  1. An environmental scan of an aged care workplace using the PARiHS model: assessing preparedness for change.

    PubMed

    Gibb, Heather

    2013-03-01

    The environmental scan aimed to deepen our understanding of the aged care work culture and to ascertain the readiness of the workers to advance towards team-based quality care provision. The workplace context was a high-care unit within a large residential aged care facility. We used the Promoting Action on Research Implementation in Health Services (PARiHS) framework to assess workplace readiness via interviews, individual surveys and observation of practice. A profile of current culture emerged as mutually supportive and task focused, but at the same time lacking corporate team features of shared decision-making and feedback for practice improvement. However, latent within the frontline leaders and personal care staff, there was evidence of some embedded knowledge and capacity for corporate team performance. This study has validated an evidence-based method for conducting environmental scanning in aged care, recommended before any major change is introduced. Environmental scanning helps gauge workforce capacity and limitations; this information can enable managers to capitalize on identified cultural strengths to fortify change and avoid pitfalls of personal and collective vulnerabilities. © 2012 Blackwell Publishing Ltd.

  2. Improving three-tier environmental assessment model by using a 3D scanning FLS-AM series hyperspectral lidar

    NASA Astrophysics Data System (ADS)

    Samberg, Andre; Babichenko, Sergei; Poryvkina, Larisa

    2005-05-01

    Delay between the time when natural disaster, for example, oil accident in coastal water, occurred and the time when environmental protection actions, for example, water and shoreline clean-up, started is of significant importance. Mostly remote sensing techniques are considered as (near) real-time and suitable for multiple tasks. These techniques in combination with rapid environmental assessment methodologies would form multi-tier environmental assessment model, which allows creating (near) real-time datasets and optimizing sampling scenarios. This paper presents the idea of three-tier environmental assessment model. Here all three tiers are briefly described to show the linkages between them, with a particular focus on the first tier. Furthermore, it is described how large-scale environmental assessment can be improved by using an airborne 3-D scanning FLS-AM series hyperspectral lidar. This new aircraft-based sensor is typically applied for oil mapping on sea/ground surface and extracting optical features of subjects. In general, a sampling network, which is based on three-tier environmental assessment model, can include ship(s) and aircraft(s). The airborne 3-D scanning FLS-AM series hyperspectral lidar helps to speed up the whole process of assessing of area of natural disaster significantly, because this is a real-time remote sensing mean. For instance, it can deliver such information as georeferenced oil spill position in WGS-84, the estimated size of the whole oil spill, and the estimated amount of oil in seawater or on ground. All information is produced in digital form and, thus, can be directly transferred into a customer"s GIS (Geographical Information System) system.

  3. Early- to Mid-Holocene environmental and climate changes in the southern Baltic lowland using XRF scanning data

    NASA Astrophysics Data System (ADS)

    Tjallingii, Rik; Ott, Florian; Dräger, Nadine; Kramkowski, Mateusz; Slowinski, Michal; Brauer, Achim

    2016-04-01

    The ICLEA project includes several annually laminated (varved) lake records from the southern Baltic lowlands for detailed climatic and environmental reconstructions. Continuous geochemical records have been obtained by XRF scanning and reveal the dominant depositional processes of the German lake Tiefer See and the Polish lakes Głęboczek, Czechowskie and Jelonek. Each lake record has been independently dated by means of varve counting, AMS 14C dating and tephrochronology. The unprecedented age control allows accurate age correlation of individual lake records even over large distances. The detailed stratigraphy is used in combination with micro-XRF core scanning records to link depositional variability with past environmental and climatic changes. However, in each lake the major sedimentological transitions are reflected by different geochemical elements due to the different depositional conditions. Here we present a statistical concept for XRF core scanning data to evaluate the timing and frequency of the most prominent sedimentological transitions of the Early to Mid Holocene. Preliminary results reveal that depositional conditions prevail over relatively long periods (102-103 yrs) between the Younger Dryas and ~6000 yrs. The sedimentological transitions during this period are associated to regional climatic changes in the southern Baltic lowlands during this period. After ~6000 yrs BP, depositional conditions vary at a much higher frequency (10-102 yrs), which are associated with a stronger local and lake internal environmental variability. Ongoing research focuses on a multi-proxy approach to further constrain possible links between depositional changes recorded in these varved lacustrine sediments with Early- to Mid-Holocene climatic and environmental variations. This study is a contribution to the Virtual Institute of Integrated Climate and Landscape Evolution Analysis - ICLEA - of the Helmholtz Association.

  4. Identification of outliers in a genomic scan for selection along environmental gradients in the bamboo locust, Ceracris kiangsu

    PubMed Central

    Feng, Xiao-Jing; Jiang, Guo-Fang; Fan, Zhou

    2015-01-01

    Identification of loci under divergent selection is a key step in understanding the evolutionary process because those loci are responsible for the genetic variations that affect fitness in different environments. Understanding how environmental forces give rise to adaptive genetic variation is a challenge in pest control. Here, we performed an amplified fragment length polymorphism (AFLP) genome scan in populations of the bamboo locust, Ceracris kiangsu, to search for candidate loci that are influenced by selection along an environmental gradient in southern China. In outlier locus detection, loci that demonstrate significantly higher or lower among-population genetic differentiation than expected under neutrality are identified as outliers. We used several outlier detection methods to study the features of C. kiangsu, including method DFDIST, BayeScan, and logistic regression. A total of 97 outlier loci were detected in the C. kiangsu genome with very high statistical supports. Moreover, the results suggested that divergent selection arising from environmental variation has been driven by differences in temperature, precipitation, humidity and sunshine. These findings illustrate that divergent selection and potential local adaptation are prevalent in locusts despite seemingly high levels of gene flow. Thus, we propose that native environments in each population may induce divergent natural selection. PMID:26333424

  5. Visualisation of natural aquatic colloids and particles -- a comparison of conventional high vacuum and environmental scanning electron microscopy.

    PubMed

    Doucet, Frederic J; Lead, Jamie R; Maguire, Leanne; Achterberg, Eric P; Millward, Geoff E

    2005-02-01

    The applicability of environmental scanning electron microscopy (ESEM; imaging of hydrated samples) and conventional high vacuum scanning electron microscopy (SEM; imaging of dried samples at high vacuum) for the observation of natural aquatic colloids and particles was explored and compared. Specific attention was given to the advantages and limitations of these two techniques when used to assess the sizes and morphologies of complex and heterogeneous environmental systems. The observation of specimens using SEM involved drying and coating, whereas ESEM permitted their examination in hydrated form without prior sample preparation or conductive coating. The two techniques provided significantly different micrographs of the same sample. SEM provided sharper images, lower resolution limits (10 nm or lower), but more densely packed particles, suggesting aggregation, and different morphological features than ESEM, suggesting artefacts due to drying. ESEM produced less easily visualised materials, more complex interpretation, slightly higher resolution limits (30-50 nm), but these limitations were more than compensated for by the fact that ESEM samples retained, at least to some extent, their morphological integrity. The results in this paper show that SEM and ESEM should be regarded as complementary techniques for the study of aquatic colloids and particles and that ESEM should be more widely applied to aquatic environmental systems than hitherto.

  6. Organizations as Information Processing Systems. Environmental Characteristics, Company Performance, and Chief Executive Scanning: An Empirical Study.

    DTIC Science & Technology

    1986-04-01

    perhaps more than any other factor, affects organizatlonal structure, internal processes, and managerial decision making (Duncan, 1972; Ptetfer and...company, call. an immediate subordinate, or read an internal report or professional journal. Top management scanning tends to be irregular rather than...Mode is derived from Aguilar’s (19b7) designation of information sources as personal, impersonal, internal or external.. Scanni ngj fretncy. Research

  7. Visible infrared spin-scan radiometers (VISSR) for the Geostationary Operational Environmental Satellite (GOES) B and C application

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Two visible infrared spin scan radiometer (VISSR) instruments provided for the Geostationary Operational Environmental Satellite B and C (GOES B and C) spacecrafts are described. The instruments are identical to those supplied previously are summarized. A significant number of changes primarily involving corrections of drawing errors and omissions were also performed. All electrical changes were breadboarded (where complexity required this), were incorporated into the test module, and subjected to verification of proper operation throughout fall instrument temperature range. Evaluation of the changes also included design operating safety margins to account for component variations and life.

  8. Observation of a brine layer on an ice surface with an environmental scanning electron microscope at higher pressures and temperatures.

    PubMed

    Krausko, Ján; Runštuk, Jiří; Neděla, Vilém; Klán, Petr; Heger, Dominik

    2014-05-20

    Observation of a uranyl-salt brine layer on an ice surface using backscattered electron detection and ice surface morphology using secondary-electron detection under equilibrium conditions was facilitated using an environmental scanning electron microscope (ESEM) at temperatures above 250 K and pressures of hundreds of Pa. The micrographs of a brine layer over ice grains prepared by either slow or shock freezing provided a complementary picture of the contaminated ice grain boundaries. Fluorescence spectroscopy of the uranyl ions in the brine layer confirmed that the species exists predominately in the solvated state under experimental conditions of ESEM.

  9. Quality improvement of environmental secondary electron detector signal using helium gas in variable pressure scanning electron microscopy.

    PubMed

    Oho, Eisaku; Suzuki, Kazuhiko; Yamazaki, Sadao

    2007-01-01

    The quality of the image signal obtained from the environmental secondary electron detector (ESED) employed in a variable pressure (VP) SEM can be dramatically improved by using helium gas. The signal-to-noise ratio (SNR) increases gradually in the range of the pressures that can be used in our modified SEM. This method is especially useful in low-voltage VP SEM as well as in a variety of SEM operating conditions, because helium gas can more or less maintain the amount of unscattered primary electrons. In order to measure the SNR precisely, a digital scan generator system for obtaining two images with identical views is employed as a precondition.

  10. Study of environmental biodegradation of LDPE films in soil using optical and scanning electron microscopy.

    PubMed

    Mumtaz, Tabassum; Khan, M R; Hassan, Mohd Ali

    2010-07-01

    An outdoor soil burial test was carried out to evaluate the degradation of commercially available LDPE carrier bags in natural soil for up to 2 years. Biodegradability of low density polyethylene films in soil was monitored using both optical and scanning electron microscopy (SEM). After 7-9 months of soil exposure, microbial colonization was evident on the film surface. Exposed LDPE samples exhibit progressive changes towards degradation after 17-22 months. SEM images reveal signs of degradation such as exfoliation and formation of cracks on film leading to disintegration. The possible degradation mode and consequences on the use and disposal of LDPE films is discussed.

  11. On the Horizon. The Environmental Scanning Newsletter for Leaders in Education, 1993-1994.

    ERIC Educational Resources Information Center

    Morrison, James L., Ed.

    1994-01-01

    This compilation of five newsletter issues focuses on potential developments and critical trends in higher education. It reports news from the social, technological, economic, environmental, and political sectors. It also includes a regular column titled "The Situation Room," a column on instructional tools, a column about Internet, and…

  12. Bottlenecks in bog pine multiplication by somatic embryogenesis and their visualization with the environmental scanning electron microscope.

    PubMed

    Vlašínová, Helena; Neděla, Vilem; Đorđević, Biljana; Havel, Ladislav

    2016-10-25

    Somatic embryogenesis (SE) is an important biotechnological technique used for the propagation of many pine species in vitro. However, in bog pine, one of the most endangered tree species in the Czech Republic, limitations were observed, which negatively influenced the development and further germination of somatic embryos. Although initiation frequency was very low-0.95 %, all obtained cell lines were subjected to maturation. The best responding cell line (BC1) was used and subjected to six different variants of the maturation media. The media on which the highest number of early-precotyledonary/cotyledonary somatic embryos was formed was supplemented with 121 μM abscisic acid (ABA) and with 6 % maltose. In the end of maturation experiments, different abnormalities in formation of somatic embryos were observed. For visualization and identification of abnormalities in meristem development during proliferation and maturation processes, the environmental scanning electron microscope was used. In comparison to the classical light microscope, the non-commercial environmental scanning electron microscope AQUASEM II has been found as a very useful tool for the quick recognition of apical meristem disruption and abnormal development. To our knowledge, this is the first report discussing somatic embryogenesis in bog pine. Based on this observation, the cultivation procedure could be enhanced and the method for SE of bog pine optimized.

  13. The Debrecen Scanning Nuclear Microprobe and its Applications in Biology and Environmental Science

    SciTech Connect

    Kertesz, Zsofia

    2007-11-26

    Nuclear microscopy is one of the most powerful tools which are able to determine quantitative trace element distributions in complex samples on a microscopic scale. The advantage of nuclear microprobes are that different ion beam analytical techniques, like PIXE, RBS, STIM and NRA can be applied at the same time allowing the determination of the sample structure, major, minor and trace element distribution simultaneously.In this paper a nuclear microprobe setup developed for the microanalysis of thin complex samples of organic matrix at the Debrecen Scanning Nuclear Microprobe Facility is presented. The application of nuclear microscopy in life sciences is shown through an example, the study of penetration of TiO{sub 2} nanoparticles of bodycare cosmetics in skin layers.

  14. Miniature environmental chamber enabling in situ scanning probe microscopy within reactive environments.

    PubMed

    Nonnenmann, Stephen S; Bonnell, Dawn A

    2013-07-01

    Developments in solid oxide fuel cells (SOFCs) continue to be one of the most intensely studied areas involving energy-producing systems, in an attempt to partially alleviate rapidly growing energy concerns. Direct, experimental observation of the governing electrochemical processes have remained largely elusive, due to high operating temperatures in the range of 400 °C-1000 °C. Here we outline the design and development of a miniature environmental chamber that enables a standard atomic force microscopes access to realistic SOFC operating conditions (T = 600 °C) for direct interrogation of electrochemical phenomena within SOFC cross-sections.

  15. Quantification of rapid environmental redox processes with quick-scanning x-ray absorption spectroscopy (Q-XAS).

    PubMed

    Ginder-Vogel, Matthew; Landrot, Gautier; Fischel, Jason S; Sparks, Donald L

    2009-09-22

    Quantification of the initial rates of environmental reactions at the mineral/water interface is a fundamental prerequisite to determining reaction mechanisms and contaminant transport modeling and predicting environmental risk. Until recently, experimental techniques with adequate time resolution and elemental sensitivity to measure initial rates of the wide variety of environmental reactions were quite limited. Techniques such as electron paramagnetic resonance and Fourier transform infrared spectroscopies suffer from limited elemental specificity and poor sensitivity to inorganic elements, respectively. Ex situ analysis of batch and stirred-flow systems provides high elemental sensitivity; however, their time resolution is inadequate to characterize rapid environmental reactions. Here we apply quick-scanning x-ray absorption spectroscopy (Q-XAS), at sub-second time-scales, to measure the initial oxidation rate of As(III) to As(V) by hydrous manganese(IV) oxide. Using Q-XAS, As(III) and As(V) concentrations were determined every 0.98 s in batch reactions. The initial apparent As(III) depletion rate constants (t < 30 s) measured with Q-XAS are nearly twice as large as rate constants measured with traditional analytical techniques. Our results demonstrate the importance of developing analytical techniques capable of analyzing environmental reactions on the same time scale as they occur. Given the high sensitivity, elemental specificity, and time resolution of Q-XAS, it has many potential applications. They could include measuring not only redox reactions but also dissolution/precipitation reactions, such as the formation and/or reductive dissolution of Fe(III) (hydr)oxides, solid-phase transformations (i.e., formation of layered-double hydroxide minerals), or almost any other reaction occurring in aqueous media that can be measured using x-ray absorption spectroscopy.

  16. Nanogold In Situ Hybridization for Phylogenetic Identification in Geologic Samples Using Environmental Scanning Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Ehrhardt, C.; Haymon, R.; Sievert, S.; Holden, P.

    2006-12-01

    Collecting phylogenetic information simultaneously with mineral textures and associations for geomicrobiological studies has always been a challenge. Recently a new type of nucleotide reporter system has been developed that utilizes small particles of nanogold (1.4 nm) covalently attached to oligonucelotide probes. Due to the small size and electron density of these nanogold reporter molecules, this in situ hybridization technique allows for the phylogenetic identification of microbial targets with a scanning electron microscope. Here we present new applications of the nanogold hybridization technique for pure cultures and natural microbial communities in a range of geologic samples including sand grains, basalt chips incubated on deep sea hydrothermal vents, and gypsum crusts sampled from a saline lake. While we do observe nonspecific binding of nanogold probes to minerals and organic compounds in geologic matrices, this can be distinguished from positive hybridization events with a spatial variety analysis. To assess the potential of nanogold hybridizations for quantitative assessments of microbial communities, fluorescent in situ hybridizations (FISH) were performed on all samples and compared to cell counts generated from nanogold hybridizations.

  17. Characterization of self-healing glassy composites by high-temperature environmental scanning electron microscopy (HT-ESEM).

    PubMed

    Coillot, Daniel; Podor, Renaud; Méar, François O; Montagne, Lionel

    2010-01-01

    In situ high-temperature healing of cracks in composites made of glass and vanadium boride (VB) particles was observed using an environmental scanning electron microscope equipped with a high-temperature chamber (HT-ESEM). HT-ESEM is an adequate tool for studying the self-healing property of these materials. The change in crack length as a function of redox atmospheric conditions is reported. No self-healing behaviour was observed under reducing conditions, while a complete and rapid healing of the cracks was measured under oxidizing conditions. HT-ESEM image analyses enabled the monitoring of the healing effect. The self-healing mechanism was identified as a consequence of the VB active particles oxidation and subsequent pouring of fluid oxides into the cracks. These innovative composites offer an interesting potential in the domain of solid oxide fuel cell sealants.

  18. Comparative analysis of Trichuris muris surface using conventional, low vacuum, environmental and field emission scanning electron microscopy.

    PubMed

    Lopes Torres, Eduardo José; de Souza, Wanderley; Miranda, Kildare

    2013-09-23

    The whipworm of the genus Trichuris Roederer, 1791, is a nematode of worldwide distribution and comprises species that parasitize humans and other mammals. Infections caused by Trichuris spp. in mammals can lead to various intestinal diseases of human and veterinary interest. The morphology of Trichuris spp. and other helminths has been mostly studied using conventional scanning electron microscopy of chemically fixed, dried and metal-coated specimens, although this kind of preparation has been shown to introduce a variety of artifacts such as sample shrinking, loss of secreted products and/or hiding of small structures due to sample coating. Low vacuum (LVSEM) and environmental scanning electron microscopy (ESEM) have been applied to a variety of insulator samples, also used in the visualization of hydrated and/or live specimens in their native state. In the present work, we used LVSEM and ESEM to analyze the surface of T. muris and analyze its interaction with the host tissue using freshly fixed or unfixed hydrated samples. Analysis of hydrated samples showed a set of new features on the surface of the parasite and the host tissue, including the presence of the secretory products of the bacillary glands on the surface of the parasite, and the presence of mucous material and eggs on the intestinal surface. Field emission scanning electron microscopy (FESEM) was also applied to reveal the detailed structure of the glandular chambers in fixed, dried and metal coated samples. Taken together, the results show that analysis of hydrated samples may provide new insights in the structural organization of the surface of helminth parasites and its interaction with the infected tissue, suggesting that the application of alternative SEM techniques may open new perspectives for analysis in taxonomy, morphology and host-parasite interaction fields. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Post-market drug evaluation research training capacity in Canada: an environmental scan of Canadian educational institutions.

    PubMed

    Wiens, Matthew O; Soon, Judith A; MacLeod, Stuart M; Sharma, Sunaina; Patel, Anik

    2014-01-01

    Ongoing efforts by Health Canada intended to modernize the legislation and regulation of pharmaceuticals will help improve the safety and effectiveness of drug products. It will be imperative to ensure that comprehensive and specialized training sites are available to train researchers to support the regulation of therapeutic products. The objective of this educational institution inventory was to conduct an environmental scan of educational institutions in Canada able to train students in areas of post-market drug evaluation research. A systematic web-based environmental scan of Canadian institutions was conducted. The website of each university was examined for potential academic programs. Six core programmatic areas were determined a priori as necessary to train competent post-market drug evaluation researchers. These included biostatistics, epidemiology, pharmacoepidemiology, health economics or pharmacoeconomics, pharmacogenetics or pharmacogenomics and patient safety/pharmacovigilance. Twenty-three academic institutions were identified that had the potential to train students in post-market drug evaluation research. Overall, 23 institutions taught courses in epidemiology, 22 in biostatistics, 17 in health economics/pharmacoeconomics, 5 in pharmacoepidemiology, 5 in pharmacogenetics/pharmacogenomics, and 3 in patient safety/pharmacovigilance. Of the 23 institutions, only the University of Ottawa offered six core courses. Two institutions offered five, seven offered four and the remaining 14 offered three or fewer. It is clear that some institutions may offer programs not entirely reflected in the nomenclature used for this review. As Heath Canada moves towards a more progressive licensing framework, augmented training to increase research capacity and expertise in drug safety and effectiveness is timely and necessary.

  20. Medical versus surgical methods of early abortion: protocol for a systematic review and environmental scan of patient decision aids

    PubMed Central

    Donnelly, Kyla Z; Thompson, Rachel

    2015-01-01

    Introduction Currently, we lack understanding of the content, quality and impact of patient decision aids to support decision-making between medical and surgical methods of early abortion. We plan to undertake a systematic review of peer-reviewed literature to identify, appraise and describe the impact of early abortion method decision aids evaluated quantitatively (Part I), and an environmental scan to identify and appraise other early abortion method decision aids developed in the US (Part II). Methods and analysis For the systematic review, we will search PubMed, Cochrane Library, CINAHL, EMBASE and PsycINFO databases for articles describing experimental and observational studies evaluating the impact of an early abortion method decision aid on women's decision-making processes and outcomes. For the environmental scan, we will identify decision aids by supplementing the systematic review search with Internet-based searches and key informant consultation. The primary reviewer will assess all studies and decision aids for eligibility, and a second reviewer will also assess a subset of these. Both reviewers will independently assess risk of bias in the studies and abstract data using a piloted form. Finally, both reviewers will assess decision aid quality using the International Patient Decision Aid Standards criteria, ease of readability using Flesch/Flesch-Kincaid tests, and informational content using directed content analysis. Ethics and dissemination As this study does not involve human subjects, ethical approval will not be sought. We aim to disseminate the findings in a scientific journal, via academic and/or professional conferences and among the broader community to contribute knowledge about current early abortion method decision-making support. Trial registration number This protocol is registered in the International Prospective Register of Systematic Reviews (CRD42015016717). PMID:26173718

  1. The Effect of Electron Beam Irradiation in Environmental Scanning Transmission Electron Microscopy of Whole Cells in Liquid.

    PubMed

    Hermannsdörfer, Justus; Tinnemann, Verena; Peckys, Diana B; de Jonge, Niels

    2016-06-01

    Whole cells can be studied in their native liquid environment using electron microscopy, and unique information about the locations and stoichiometry of individual membrane proteins can be obtained from many cells thus taking cell heterogeneity into account. Of key importance for the further development of this microscopy technology is knowledge about the effect of electron beam radiation on the samples under investigation. We used environmental scanning electron microscopy (ESEM) with scanning transmission electron microscopy (STEM) detection to examine the effect of radiation for whole fixed COS7 fibroblasts in liquid. The main observation was the localization of nanoparticle labels attached to epidermal growth factor receptors (EGFRs). It was found that the relative distances between the labels remained mostly unchanged (<1.5%) for electron doses ranging from the undamaged native state at 10 e-/Å2 toward 103 e-/Å2. This dose range was sufficient to determine the EGFR locations with nanometer resolution and to distinguish between monomers and dimers. Various different forms of radiation damage became visible at higher doses, including severe dislocation, and the dissolution of labels.

  2. Evaluation of environmental scanning electron microscopy for analysis of Proteus mirabilis crystalline biofilms in situ on urinary catheters.

    PubMed

    Holling, Nina; Dedi, Cinzia; Jones, Caroline E; Hawthorne, Joseph A; Hanlon, Geoffrey W; Salvage, Jonathan P; Patel, Bhavik A; Barnes, Lara M; Jones, Brian V

    2014-06-01

    Proteus mirabilis is a common cause of catheter-associated urinary tract infections and frequently leads to blockage of catheters due to crystalline biofilm formation. Scanning electron microscopy (SEM) has proven to be a valuable tool in the study of these unusual biofilms, but entails laborious sample preparation that can introduce artefacts, undermining the investigation of biofilm development. In contrast, environmental scanning electron microscopy (ESEM) permits imaging of unprocessed, fully hydrated samples, which may provide much insight into the development of P. mirabilis biofilms. Here, we evaluate the utility of ESEM for the study of P. mirabilis crystalline biofilms in situ, on urinary catheters. In doing so, we compare this to commonly used conventional SEM approaches for sample preparation and imaging. Overall, ESEM provided excellent resolution of biofilms formed on urinary catheters and revealed structures not observed in standard SEM imaging or previously described in other studies of these biofilms. In addition, we show that energy-dispersive X-ray spectroscopy (EDS) may be employed in conjunction with ESEM to provide information regarding the elemental composition of crystalline structures and demonstrate the potential for ESEM in combination with EDS to constitute a useful tool in exploring the mechanisms underpinning crystalline biofilm formation.

  3. Immobilization of zebrafish larvae on a chip-based device for environmental scanning electron microscopy (ESEM) imaging

    NASA Astrophysics Data System (ADS)

    Akagi, Jin; Hall, Chris J.; Crosier, Kathryn E.; Crosier, Philip S.; Wlodkowic, Donald

    2013-12-01

    Small vertebrate model organisms have recently gained popularity as attractive experimental models that enhance our understanding of human tissue and organ development. Laser microsurgery on zebrafish larvae combined with Scanning Electron Microscopy (SEM) imaging can in particular provide accelerated insights into the tissue regeneration phenomena. Conventional SEM exposes, however, specimens to high vacuum environments, and often requires laborintensive and time-consuming pretreatments and manual positioning. Moreover, there are virtually no technologies available that can quickly immobilize the zebrafish larvae for high definition SEM imaging. This work describes the proof-of-concept design and validation of a microfluidic chip-based system for immobilizing zebrafish larvae and it's interfacing with Environmental Scanning Electron Microscope (ESEM) imaging. The Lab-on-a-Chip (LOC) device was fabricated using a high-speed infrared laser micromachining and consists of a reservoir with multiple semispherical microwells, which hold the yolk of zebrafish larvae, and drain channels that allow removing excess of medium during SEM imaging. Paper filter is used to actuate the chip and immobilization of the larvae by gentle suction that occurs during water drainage. The trapping region allows multiple specimens to be positioned on the chip. The device is then inserted directly inside the ESEM and imaged in a near 100% humidity atmosphere. This facilitates ESEM imaging of untreated biological samples.

  4. Evaluation of environmental scanning electron microscopy for analysis of Proteus mirabilis crystalline biofilms in situ on urinary catheters

    PubMed Central

    Holling, Nina; Dedi, Cinzia; Jones, Caroline E; Hawthorne, Joseph A; Hanlon, Geoffrey W; Salvage, Jonathan P; Patel, Bhavik A; Barnes, Lara M; Jones, Brian V

    2014-01-01

    Proteus mirabilis is a common cause of catheter-associated urinary tract infections and frequently leads to blockage of catheters due to crystalline biofilm formation. Scanning electron microscopy (SEM) has proven to be a valuable tool in the study of these unusual biofilms, but entails laborious sample preparation that can introduce artefacts, undermining the investigation of biofilm development. In contrast, environmental scanning electron microscopy (ESEM) permits imaging of unprocessed, fully hydrated samples, which may provide much insight into the development of P. mirabilis biofilms. Here, we evaluate the utility of ESEM for the study of P. mirabilis crystalline biofilms in situ, on urinary catheters. In doing so, we compare this to commonly used conventional SEM approaches for sample preparation and imaging. Overall, ESEM provided excellent resolution of biofilms formed on urinary catheters and revealed structures not observed in standard SEM imaging or previously described in other studies of these biofilms. In addition, we show that energy-dispersive X-ray spectroscopy (EDS) may be employed in conjunction with ESEM to provide information regarding the elemental composition of crystalline structures and demonstrate the potential for ESEM in combination with EDS to constitute a useful tool in exploring the mechanisms underpinning crystalline biofilm formation. PMID:24786314

  5. Hydrogen-enhanced cracking revealed by in situ micro-cantilever bending test inside environmental scanning electron microscope.

    PubMed

    Deng, Yun; Hajilou, Tarlan; Barnoush, Afrooz

    2017-07-28

    To evaluate the hydrogen (H)-induced embrittlement in iron aluminium intermetallics, especially the one with stoichiometric composition of 50 at.% Al, a novel in situ micro-cantilever bending test was applied within an environmental scanning electron microscope (ESEM), which provides both a full process monitoring and a clean, in situ H-charging condition. Two sets of cantilevers were analysed in this work: one set of un-notched cantilevers, and the other set with focused ion beam-milled notch laying on two crystallographic planes: (010) and (110). The cantilevers were tested under two environmental conditions: vacuum (approximately 5 × 10(-4) Pa) and ESEM (450 Pa water vapour). Crack initiation at stress-concentrated locations and propagation to cause catastrophic failure were observed when cantilevers were tested in the presence of H; while no cracking occurred when tested in vacuum. Both the bending strength for un-notched beams and the fracture toughness for notched beams were reduced under H exposure. The hydrogen embrittlement (HE) susceptibility was found to be orientation dependent: the (010) crystallographic plane was more fragile to HE than the (110) plane.This article is part of the themed issue 'The challenges of hydrogen and metals'. © 2017 The Author(s).

  6. Hydrogen-enhanced cracking revealed by in situ micro-cantilever bending test inside environmental scanning electron microscope

    NASA Astrophysics Data System (ADS)

    Deng, Yun; Hajilou, Tarlan; Barnoush, Afrooz

    2017-06-01

    To evaluate the hydrogen (H)-induced embrittlement in iron aluminium intermetallics, especially the one with stoichiometric composition of 50 at.% Al, a novel in situ micro-cantilever bending test was applied within an environmental scanning electron microscope (ESEM), which provides both a full process monitoring and a clean, in situ H-charging condition. Two sets of cantilevers were analysed in this work: one set of un-notched cantilevers, and the other set with focused ion beam-milled notch laying on two crystallographic planes: (010) and (110). The cantilevers were tested under two environmental conditions: vacuum (approximately 5 × 10-4 Pa) and ESEM (450 Pa water vapour). Crack initiation at stress-concentrated locations and propagation to cause catastrophic failure were observed when cantilevers were tested in the presence of H; while no cracking occurred when tested in vacuum. Both the bending strength for un-notched beams and the fracture toughness for notched beams were reduced under H exposure. The hydrogen embrittlement (HE) susceptibility was found to be orientation dependent: the (010) crystallographic plane was more fragile to HE than the (110) plane. This article is part of the themed issue 'The challenges of hydrogen and metals'.

  7. Inspection of anode and field wires for the COMPASS drift chamber, DC5, with Environmental Scanning Electron Microscope

    NASA Astrophysics Data System (ADS)

    Cyuzuzo, Sonia

    2014-09-01

    The COMPASS experiment at CERN uses a secondary pion beam from the Super Proton Synchrotron (SPS) at CERN to explore the spin structure of nucleons. A new drift chamber, DC5, will be integrated into the COMPASS spectrometer to replace an aging straw tube detector. DC5 will detect muon pairs from Drell-Yan scattering of a pion-beam off a transversely polarized proton target. This data will be used to determine the correlation between transverse proton spin and the intrinsic transverse momentum of up-quarks inside the proton, the Sivers effect. DC5 is a large area planar drift chamber with 8 layers of anode-frames made of G10 fiberglass-epoxy. The G10 frames support printed circuit boards for soldering 20 μm diameter anode and 100 μm diameter field wires. The anode planes are sandwiched by 13 graphite coated Mylar cathode planes. To ensure a well-functioning of DC5, the wires were carefully tested. An optical inspection and a spectral analysis was performed with an Environmental Scanning Electron Microscope (ESEM) to verify the composition and dimensions and the integrity of the gold plating on the surface of these wires. The spectra of the wires were studied at 10 and 30 keV. The COMPASS experiment at CERN uses a secondary pion beam from the Super Proton Synchrotron (SPS) at CERN to explore the spin structure of nucleons. A new drift chamber, DC5, will be integrated into the COMPASS spectrometer to replace an aging straw tube detector. DC5 will detect muon pairs from Drell-Yan scattering of a pion-beam off a transversely polarized proton target. This data will be used to determine the correlation between transverse proton spin and the intrinsic transverse momentum of up-quarks inside the proton, the Sivers effect. DC5 is a large area planar drift chamber with 8 layers of anode-frames made of G10 fiberglass-epoxy. The G10 frames support printed circuit boards for soldering 20 μm diameter anode and 100 μm diameter field wires. The anode planes are sandwiched by 13

  8. CSSP Environmental Scan 2013

    DTIC Science & Technology

    2014-09-01

    human cases and 377 fatalities according to the World Health Organization (WHO) [52]. Another particularly deadly strain of influenza ( H7N9 ) appeared...EN_GIP_20130705CumulativeNum berH5N1cases_2.pdf. [53] World Health Organization, “Human Infection with Avian Influenza A ( H7N9 ) Virus – Update,” 20 July 2013

  9. Comparison of Environmental Scanning Electron Microscopy in Low Vacuum or wet mode for the investigation of cell biomaterial interactions.

    PubMed

    Mattarozzi, Monica; Manfredi, Edoardo; Lorenzi, Andrea; Smerieri, Arianna; Di Blasio, Alberto; Macaluso, Guido; Lumetti, Simone; Galli, Carlo

    2016-05-06

    The aim of the present study was to investigate the efficacy of environmental scanning electron microscopy (ESEM), in low vacuum mode (LV-ESEM) and in wet mode (wet-ESEM) in the assessment of cell-material interactions. Mouse calvaria MC3T3 cells (ATCC) were seeded on commercially pure machined titanium discs of 10 mm diameter in Dulbecco modified MEM, 10% Fetal Bovine Serum, 1% Penicillin and Streptomycin and 1% Glutamine. Samples were then processed for microscope observation by rinse in Phosphate Buffer saline and fixation in 4.5% Glutaraldehyde. Samples were then rinsed in Sodium Cacodylate buffer and observed or dehydrated in alcohol prior to LV-ESEM observation. Fresh samples in 0.9% NaCl solution were observed in wet- ESEM. No significant loss of detail was observed when dehydrated or non dehydrated samples were analysed at LV-ESEM.The observation of fresh samples in wet-ESEM however proved difficult for the need to eliminate water which forms a layer covering the sample, thus hiding cell surface details. When reducing the vapor pressure in the chamber, the layer evaporated and NaCl immediately started to precipitate and cells collapsed, thus no further investigation was possible. The use of low vacuum-ESEM after cell fixation, but without dehydration or gold sputter coating proved a viable alternative to traditional high vacuum SEM observation.

  10. An environmental scan of emergency response systems and services in remote First Nations communities in Northern Ontario

    PubMed Central

    Mew, E. J.; Ritchie, S. D.; VanderBurgh, D.; Beardy, J. L.; Gordon, J.; Fortune, M.; Mamakwa, S.; Orkin, A. M.

    2017-01-01

    ABSTRACT Background: Approximately 24,000 Ontarians live in remote Indigenous communities with no road access. These communities are a subset of Nishnawbe Aski Nation (NAN), a political grouping of 49 First Nations communities in Northern Ontario, Canada. Limited information is available regarding the status of emergency care in these communities. Objective: We aimed to understand emergency response systems, services, and training in remote NAN communities. Design: We used an environmental scan approach to compile information from multiple sources including community-based participatory research. This included the analysis of data collected from key informant interviews (n=10) with First Nations community health leaders and a multi-stakeholder roundtable meeting (n=33) in October 2013. Results: Qualitative analysis of the interview data revealed four issues related to emergency response systems and training: (1) inequity in response capacity and services, (2) lack of formalised dispatch systems, (3) turnover and burnout in volunteer emergency services, and (4) challenges related to first aid training. Roundtable stakeholders supported the development of a community-based emergency care system to address gaps. Conclusions: Existing first response, paramedical, and ambulance service models do not meet the unique geographical, epidemiological and cultural needs in most NAN communities. Sustainable, context-appropriate, and culturally relevant emergency care systems are needed. PMID:28494638

  11. Monitoring the osmotic response of single yeast cells through force measurement in the environmental scanning electron microscope

    NASA Astrophysics Data System (ADS)

    Jansson, Anna; Nafari, Alexandra; Hedfalk, Kristina; Olsson, Eva; Svensson, Krister; Sanz-Velasco, Anke

    2014-02-01

    We present a measurement system that combines an environmental scanning electron microscope (ESEM) and an atomic force microscope (AFM). This combination enables studies of static and dynamic mechanical properties of hydrated specimens, such as individual living cells. The integrated AFM sensor provides direct and continuous force measurement based on piezoresistive force transduction, allowing the recording of events in the millisecond range. The in situ ESEM-AFM setup was used to study Pichia pastoris wild-type yeast cells. For the first time, a quantified measure of the osmotic response of an individual yeast cell inside an ESEM is presented. With this technique, cell size changes due to humidity variations can be monitored with nanometre accuracy. In addition, mechanical properties were extracted from load-displacement curves. A Young's modulus of 13-15 MPa was obtained for the P. pastoris yeast cells. The developed method is highly interesting as a complementary tool for the screening of drugs directed towards cellular water transport activity and provides new possibilities of studying mechanosensitive regulation of aquaporins.

  12. Fiber-optic Based Spectral Cathodoluminescence: Simple and Economic Option for Use in Conventional and Environmental Scanning Electron Microscopy.

    PubMed

    Griffin; Browne

    2000-01-01

    A fiber-optic based spectral cathodoluminescence (CL) system has been successfully installed on a variable pressure "environmental" scanning electron microscope (ESEM). The fine size of the fiber (50 µm) has been found to require careful alignment. To provide this alignment, a simple X-Y translator has been used. The aligned fiber exhibits high efficiency and the system has recorded spectra at up to 3 million "counts" per sec on strongly cathodoluminescent doped yttrium aluminium garnet (YAG) samples, at 30 kV and approximately 3 nA. A resolution of 3 nm [full width half maximum (FWHM)] at 621 nm has been measured from a red laser diode spectrum, on the ESEM column. A range of uncoated materials has been measured to characterize the CL system; these materials ranged from strongly luminescent YAG to weakly luminescent polymers. Well-characterized doped zircons have also been investigated. These data suggest that the previously reported intrinsic peak from zircon is a consequence of high-beam currents.

  13. The hygroscopic behaviour of individual aerosol particles in nickel refineries as investigated by environmental scanning electron microscopy.

    PubMed

    Inerle-Hof, Marion; Weinbruch, Stephan; Ebert, Martin; Thomassen, Yngvar

    2007-04-01

    The hygroscopic properties of individual aerosol particles (1-35 microm equivalent projected area diameter) from the Roasting, Anode Casting and Electrorefining Departments of two Ni refineries were studied by environmental scanning electron microscopy (ESEM) and energy-dispersive X-ray microanalysis (EDX) at a relative humidity of 96-98% (at a temperature of 5 degrees C). In the Roasting and Anode Casting Departments, most particles (60-85% by number) showed no visible change in size or surface morphology when exposed to high relative humidity. Approximately 15-30% of the particles developed a thin water film (growth factors between 1.006 and 1.06) indicating the presence of thin surface coatings of sulfates. About 10% of the particles in the Roasting Department formed droplets (growth factors between 1.1 and 2.6) which always contained a large portion of insoluble material. In the Electrorefining Department, most particles (approximately 60%) were residues from the electrolysis bath solution. At a relative humidity of 96-98% these particles formed a solution which contained only small insoluble inclusions. About 30% of the particles in the Electrorefining Department developed thin water films. As only a small fraction of the particles increased substantially in size when exposed to high relative humidity, the deposition pattern of the total aerosol mass fraction will not be changed substantially by hygroscopic growth. The frequent occurrence of thin surface coatings of soluble material on insoluble Ni compounds has to be considered for health assessment purposes.

  14. A tensometer to study strain deformation and failure behavior of hydrated systems via in situ environmental scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Rizzieri, R.; Baker, F. S.; Donald, A. M.

    2003-10-01

    Large strain deformation and failure behavior of the mixed biopolymer gels have been investigated via in situ Environmental scanning electron microscopy (ESEM). ESEM has been employed to explore the changes in the structure of the material, while allowing the sample to stay hydrated as it was subjected to tensile strain. The "dog-bone" shaped samples were placed in a specially designed tensometer that fitted inside the ESEM specimen chamber. It was possible, therefore, to measure for the first time not only the mechanical properties of the hydrated material, but also to observe any morphological changes occurring as it was being stretched. By using a tensometer capable of keeping a sample moist over large strains, it was possible to observe hitherto unreported structural changes in gelatin-based systems subjected to uniaxial stretching. It was shown that bands were formed in the direction of the applied strain and that particles of maltodextrin included in the gelatin underwent deformation and fracture. Such observations have led to the conclusion that previous models were sometime inadequate due to the lack of in situ observation and novel approaches are required to describe these phenomena.

  15. Critical Trends and Events Affecting the Future of Texas Higher Education. Proceedings of the Texas Association for Institutional Research (TAIR) Preconference Workshop on Environmental Scanning (1995).

    ERIC Educational Resources Information Center

    Morrison, James L.

    This proceedings report describes exercises used in a workshop on environmental scanning, designed to assist institutional research officers to develop competency in establishing and maintaining an external analysis capability on their campuses. The workshop offered an opportunity for participants to experience several techniques used in…

  16. Implementation of HPV vaccination guidelines in a diverse population in Los Angeles: Results from an environmental scan of local HPV resources and needs.

    PubMed

    Baezconde-Garbanati, Lourdes; Lienemann, Brianna A; Robles, Marisela; Johnson, Ethel; Sanchez, Kathleen; Singhal, Rita; Steinberg, Jane; Jaque, Jenny M; Pentz, Mary Ann; Gruber, Stephen

    2017-09-05

    Research shows that vaccination against human papillomavirus (HPV) infection is one of the most effective methods for reducing risk for cervical cancer; it also protects against other HPV-related cancers. Controversies exist regarding HPV vaccination in several communities; which may in part explain why although rates of HPV vaccination are increasing nationwide, Los Angeles County (LAC) data show that many adolescents are still not vaccinated. These adolescents remain at high-risk for infection. Using community-based participatory principles, we conducted an environmental scan that included a literature review, the development of a community advisory board, community feedback from HPV community meetings, and interviews with stakeholders to understand attitudes toward HPV vaccination and their impact in follow through with HPV vaccines. Twenty-eight key stakeholders participated in our coalition comprised of community organizations and clinics with strong ties to the local community. This is the only coalition dedicated exclusively to improving HPV vaccine uptake in LAC. Of these, twenty-one participated in an environmental scan via qualitative interviews about HPV vaccination programs, service delivery priorities, and proposed steps to increase HPV vaccination uptake in LAC. The environmental scan revealed targets for future efforts, barriers to HPV uptake, and next steps for improving local HPV vaccination uptake rates. The environmental scan also identified local HPV vaccination interventions and resources. Although LAC has developed important efforts for vaccination, some interventions are no longer being implemented due to lack of funds; others have not been evaluated with sufficient outcome data. The risk for cervical and other HPV-related cancers could be greatly reduced in LAC if a multilevel, multicultural, and multilingual approach is taken to better understand rates of HPV vaccination uptake, particularly among racial/ethnic minorities and LGBTQ youth

  17. Recycling stainless steel orthodontic brackets with Er:YAG laser - An environmental scanning electron microscope and shear bond strength study.

    PubMed

    Chacko, Prince K; Kodoth, Jithesh; John, Jacob; Kumar, Kishore

    2013-07-01

    TO DETERMINE THE EFFICIENCY OF ERBIUM: Yttrium aluminum garnet (Er:YAG) laser with Environmental Scanning Electron Microscope (ESEM) and shear bond strength analysis as a method of recycling stainless steel orthodontic brackets and compare with other methods of recycling. Eighty samples of extracted premolar teeth bonded to SS brackets were tested for rebonded shear bond strength after recycling by four methods and compared with a control group of 20 samples. These 80 samples were randomized into four groups which were recycled by four methods, namely, sandblasting, thermal method, adhesive grinding by tungsten carbide bur, and Er: YAG laser method. After recycling, ESEM and shear bond strength analysis were used to analyze the efficiency of the recycling methods. ER: YAG laser group was found to be having the greatest bond strength among the recycled brackets (8.33±2.51 followed by the sandblasting at 6.12±1.12 MPa, thermal and electropolishing at 4.44±0.95 MPa, and lastly the adhesive grinding method at 3.08±1.07 MPa. The shear bond strength of Er: YAG laser group was found to be having no statistically significant difference with that of the control group (P>0.05 and had statistical signifance with sandblasting, thermal and electropolishing and adhesive grinding groups at P>0.001. ESEM analysis showed complete removal of adhesive from the brackets recycled with Er: YAG laser which mimicked that of the control group. ER: YAG laser (2940 nm) was found to be the most efficient method for recycling, followed by the sandblasting, thermal, and the tungsten carbide methods, which had the least shear bond strength value and is not fit for clinical usage.

  18. Visualizing the Cu/Cu2O Interface Transition in Nanoparticles with Environmental Scanning Transmission Electron Microscopy.

    PubMed

    LaGrow, Alec P; Ward, Michael R; Lloyd, David C; Gai, Pratibha L; Boyes, Edward D

    2017-01-11

    Understanding the oxidation and reduction mechanisms of catalytically active transition metal nanoparticles is important to improve their application in a variety of chemical processes. In nanocatalysis the nanoparticles can undergo oxidation or reduction in situ, and thus the redox species are not what are observed before and after reactions. We have used the novel environmental scanning transmission electron microscope (ESTEM) with 0.1 nm resolution in systematic studies of complex dynamic oxidation and reduction mechanisms of copper nanoparticles. The oxidation of copper has previously been reported to be dependent on its crystallography and its interaction with the substrate. By following the dynamic oxidation process in situ in real time with high-angle annular dark-field imaging in the ESTEM, we use conditions ideal to track the oxidation front as it progresses across a copper nanoparticle by following the changes in the atomic number (Z) contrast with time. The oxidation occurs via the nucleation of the oxide phase (Cu2O) from one area of the nanoparticle which then progresses unidirectionally across the particle, with the Cu-to-Cu2O interface having a relationship of Cu{111}//Cu2O{111}. The oxidation kinetics are related to the temperature and oxygen pressure. When the process is reversed in hydrogen, the reduction process is observed to be similar to the oxidation, with the same crystallographic relationship between the two phases. The dynamic observations provide unique insights into redox mechanisms which are important to understanding and controlling the oxidation and reduction of copper-based nanoparticles.

  19. Scanning electron microscopy coupled with energy-dispersive X-ray spectrometry for quick detection of sulfur-oxidizing bacteria in environmental water samples

    NASA Astrophysics Data System (ADS)

    Sun, Chengjun; Jiang, Fenghua; Gao, Wei; Li, Xiaoyun; Yu, Yanzhen; Yin, Xiaofei; Wang, Yong; Ding, Haibing

    2017-01-01

    Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry (EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time (within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples.

  20. Monitoring the environmental impact of aerosol loading and dispersion from distinct industrial sources in Cubatao, Brazil, using a scanning lidar

    NASA Astrophysics Data System (ADS)

    da Costa, Renata F.; Marques, Márcia Talita Amorim; Lopes, Daniel Silveira; Guardani, Maria Lucia Goncalves; Macedo, Fernanda d. M.; Landulfo, Eduardo; Guardani, Roberto

    2016-10-01

    This paper reports the results of campaigns carried out with a scanning lidar system in an industrial area for monitoring the spatial distribution of atmospheric aerosol. The aim of the study was to verify the possibility of applying a lidar system to identify fixed sources of aerosol emission, as well as to monitor the dispersion of the emitted plume, and the ability of the system to evaluate pertinent properties of the suspended particles, such as particle number concentration and representative particle size. The data collection was carried out with a scanning backscatter lidar system in the biaxial mode with a three-wavelength light source, based on a commercial Nd:YAG laser, operating at 355 nm, 532 nm, and 1064 nm. The campaigns were carried out in an industrial site close to the city of Cubatao, Brazil, 23° 53' S and 46° 25' W, one of the largest industrial sites of the Country, comprising a steel plant, two fertilizer complexes, a cement plant and a petrochemical complex. Backscattered light intensity plots were made from the primary data collected via 360-degree scans at 15 degree elevation. The collected data correspond to distances ranging from 200 m to 1500 m from the measurement location. The results indicate that the technique can provide valuable information on the spatial and temporal distribution of aerosol concentration in the area, which therefore can represent a valuable tool in source apportionment and to validate plume dispersion models.

  1. Environmental scanning electron microscopy study of the fine structure of the triple line and cassie-wenzel wetting transition for sessile drops deposited on rough polymer substrates.

    PubMed

    Bormashenko, Edward; Bormashenko, Yelena; Stein, Tamir; Whyman, Gene; Pogreb, Roman; Barkay, Zahava

    2007-04-10

    The wetting of rough honeycomb micrometrically scaled polymer substrates was studied. A very strong dependence of the apparent contact angle on the drop volume has been established experimentally. The environmental scanning electron microscopy study of the fine structure of the triple line is reported first. The triple line is not smooth and prefers grasping the polymer matrix over air holes. The precursor rim surrounding the drop has been observed. The revealed dependence of the apparent contact angle on the drop volume is explained by the transition between the pure Cassie and combined Wenzel-Cassie wetting regimes, which is induced by capillarity penetration of water into the holes of relief.

  2. Visualising reacting single atoms under controlled conditions: Advances in atomic resolution in situ Environmental (Scanning) Transmission Electron Microscopy (E(S)TEM)

    NASA Astrophysics Data System (ADS)

    Boyes, Edward D.; Gai, Pratibha L.

    2014-02-01

    Advances in atomic resolution Environmental (Scanning) Transmission Electron Microscopy (E(S)TEM) for probing gas-solid catalyst reactions in situ at the atomic level under controlled reaction conditions of gas environment and temperature are described. The recent development of the ESTEM extends the capability of the ETEM by providing the direct visualisation of single atoms and the atomic structure of selected solid state heterogeneous catalysts in their working states in real-time. Atomic resolution E(S)TEM provides a deeper understanding of the dynamic atomic processes at the surface of solids and their mechanisms of operation. The benefits of atomic resolution-E(S)TEM to science and technology include new knowledge leading to improved technological processes with substantial economic benefits, improved healthcare, reductions in energy needs and the management of environmental waste generation. xml:lang="fr"

  3. Preparation and Loading Process of Single Crystalline Samples into a Gas Environmental Cell Holder for In Situ Atomic Resolution Scanning Transmission Electron Microscopic Observation.

    PubMed

    Straubinger, Rainer; Beyer, Andreas; Volz, Kerstin

    2016-06-01

    A reproducible way to transfer a single crystalline sample into a gas environmental cell holder for in situ transmission electron microscopic (TEM) analysis is shown in this study. As in situ holders have only single-tilt capability, it is necessary to prepare the sample precisely along a specific zone axis. This can be achieved by a very accurate focused ion beam lift-out preparation. We show a step-by-step procedure to prepare the sample and transfer it into the gas environmental cell. The sample material is a GaP/Ga(NAsP)/GaP multi-quantum well structure on Si. Scanning TEM observations prove that it is possible to achieve atomic resolution at very high temperatures in a nitrogen environment of 100,000 Pa.

  4. Step-Scan T-Cell Fourier Transform Infrared Photoacoustic Spectroscopy (FTIR-PAS) for Monitoring Environmental Air Pollutants

    NASA Astrophysics Data System (ADS)

    Liu, Lixian; Mandelis, Andreas; Melnikov, Alexander; Michaelian, Kirk; Huan, Huiting; Haisch, Christoph

    2016-07-01

    Air pollutants have adverse effects on the Earth's climate system. There is an urgent need for cost-effective devices capable of recognizing and detecting various ambient pollutants. An FTIR photoacoustic spectroscopy (FTIR-PAS) method based on a commercial FTIR spectrometer developed for air contamination monitoring will be presented. A resonant T-cell was determined to be the most appropriate resonator in view of the low-frequency requirement and space limitations in the sample compartment. Step-scan FTIR-PAS theory for regular cylinder resonator has been described as a reference for prediction of T-cell vibration principles. Both simulated amplitude and phase responses of the T-cell show good agreement with measurement data Carbon dioxide IR absorption spectra were used to demonstrate the capacity of the FTIR-PAS method to detect ambient pollutants. The theoretical detection limit for carbon dioxide was found to be 4 ppmv. A linear response to carbon dioxide concentration was found in the range from 2500 ppmv to 5000 ppmv. The results indicate that it is possible to use step-scan FTIR-PAS with a T-cell as a quantitative method for analysis of ambient contaminants.

  5. Quick Detection of Sulfur Bacteria in Environmental Water Sample with SEM(scanning electron microscopy) coupled with Energy Dispersive X-ray Spectrometry

    NASA Astrophysics Data System (ADS)

    Sun, C.; Ding, H.; Wang, Y.; Jiang, F.; Li, X.; Gao, W.; Yin, X.

    2015-12-01

    Sulfur-oxidizing bacteria play important roles in global sulfur cycle. Sulfur bacteria detection has been largely dependent on targeted gene sequencing technology or traditional cell cultivation which usually takes from days to months to finish. This cannot meet the requirements of some time-sensitive samples and/or complicated environmental samples. Since Energy-Dispersive X-ray Spectrometry (EDS) can be used to simultaneously detect multiple elements including sulfur in a sample with minimal sample treatment, the technology was applied to detect sulfur bacteria through the high sulfur content in the bacteria cell. We report the application of SEM (scanning electron microscopy) imaging coupled with EDS mapping for direct and quick detection of sulfur oxidizer in contaminated environmental water samples. The presence of sulfur bacteria can be confirmed within 24 hours after sampling. Subsequent 16S RNA gene sequencing results found the bacteria detected had over 99% similarity to Chromatium Okenii, confirming the bacterium was a sulfur oxidizer. The developed technique made it possible to quickly detect sulfur oxidizer in environmental sample and could have wide applications in sulfur bacteria detection in environmental water samples.

  6. Genome scan to assess the respective role of host-plant and environmental constraints on the adaptation of a widespread insect.

    PubMed

    Manel, Stéphanie; Conord, Cyrille; Després, Laurence

    2009-12-10

    The evolutionary success of phytophagous insects could result from their adaptation to different host-plants. Alternatively, the diversification of widespread species might be driven by adaptation along environmental gradients. To disentangle the respective roles of host-plant versus abiotic environmental variables acting on the genome of an oligophagous insect, we performed a genome scan using 83 unlinked AFLP markers on larvae of the large pine weevil collected on two host-plants (pine and spruce) in four forestry regions across Europe. At this large geographic scale, the global genetic differentiation was low and there was no isolation by distance pattern, suggesting that migration is overwhelming genetic drift in this species. In this context, the widely used frequentist methods to detect outliers (e.g. Dfdist), which assume migration - drift equilibrium are not the most appropriate approach. The implementation of a recently developed Bayesian approach, conceived to detect outliers even in non-equilibrium situations, consistently detected 9 out of 83 loci as outliers. Eight of these were validated as outliers by multiple logistic regressions: six correlated with environmental variables, one with host-plant and one with the interaction between environmental variables and host-plant. These results suggest a relatively greater importance of abiotic environmental variables, as opposed to factors linked with the host-plant, in shaping genetic differentiation across the genome in this species. Logistic regression allows the nature of factors involved in locus-specific selection to be precisely identified and represents another step forward in the process of identifying adaptive loci.

  7. Nuclear Scans

    MedlinePlus

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  8. Light, Conventional and Environmental Scanning Electron Microscopy of the Trichomes of Cucurbita pepo subsp. pepo var. styriaca and Histochemistry of Glandular Secretory Products

    PubMed Central

    KOLB, DAGMAR; MÜLLER, MARIA

    2004-01-01

    • Background and Aims In the present study, the differences between glandular and non-glandular trichomes, the secretory process and the method of secretion were studied. Previous studies on leaves of Styrian oil pumpkin (Cucurbia pepo var. styriaca) plants have shown that four morphologically and ontogenetically independent glandular and non-glandular trichome types and one bristle hair type can be distinguished. The four types of trichomes can be categorized into three glandular trichome types: type I, a short-stalked trichome with four head cells including a ‘middle-cell’, two stalk cells and one basal cell; type II, a long-stalked trichome with two head cells, a ‘neck-cell’ region and a long stalk area; type IV, a ‘stipitate-capitate’ trichome with a mesophyll cell basement, a short stalk and a multicellular head; type III, a non-glandular ‘columnar-digit’ trichome, which consists of two head cells continuous with three-celled stalk, and the basal cell. • Methods The histochemical studies (the main classes of metabolite in secreted material of glandular trichomes) were conducted in fresh and fixed hand sections, using the following tests: Sudan black B, Nile blue A, osmium tetroxide, neutral red, Naturstoffreagent A, FSA (fuchsin–safranin–astra blue), NADI (naphthol + dimethylparaphenylenediamine) and ruthenium red. Each suggested differences in the intercalations during the ontogenetical development of each trichome during the development stage. • Key Results The histochemical reactions revealed the main components of the materials secreted by all types of trichomes, which include lipids, flavones and terpenes and the different cell wall compositions. Glandular secretions were observed during environmental scanning electron microscopy (ESEM) and the trichomes compared with those seen by conventional scanning electron microscopy (CSEM). • Conclusions Scanning electron microscopy and histochemical analysis demonstrated that each of

  9. Fish scale deformation analysis using scanning electron microscope: New potential biomarker in aquatic environmental monitoring of aluminum and iron contamination

    NASA Astrophysics Data System (ADS)

    Hidayati, Dewi; Sulaiman, Norela; Othman, Shuhaimi; Ismail, B. S.

    2013-11-01

    Fish scale has the potential to be a rapid biomarker due to its structure and high possibility to come into contact with any pollutant in the aquatic environment. The scale structure consists of osteoblastic cells and other bone materials such as collagen where it is possible to form a molecular complex with heavy metals such as aluminum and iron. Hence, aluminum and iron in water could possibly destroy the scale material and marked as a scale deformation that quantitatively could be analyzed by comparing it to the normal scale structure. Water sampling and fish cage experiment were performed between June and July 2011 in Porong river which represented the water body that has high aluminum and iron contamination. The filtered water samples were preserved and extracted using the acid-mixture procedure prior to measurement of the aluminum and iron concentrations using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), while samples for total suspended solid (TSS) analysis were kept at 4 °C in cool-boxes. The scales were cleaned with sterile water, then dehydrated in 30, 50, 70, and 90% ethanol and dried on filter papers. They were then mounted on an aluminum stub and coated with gold in a sputter coater prior to Scanning Electron Microscope (SEM) observation. According to the SEM analysis, it was found that there were several deformations on the scale samples taken from sites that have high concentrations of aluminum and iron i.e. the increasing number of pits, deformation and decreasing number of spherules and ridges while the control scale exhibited the normal features. However, the site with higher TSS and pH indicated lower aluminum effect. A moderate correlation was found between the number of pits with aluminum (r=0.43) and iron (r=0.41) concentrations. Fish scale deformation using SEM analysis can potentially be a rapid biomarker in aquatic monitoring of aluminum and iron contamination. However, the measurement must be accompanied by pH and

  10. Fish scale deformation analysis using scanning electron microscope: New potential biomarker in aquatic environmental monitoring of aluminum and iron contamination

    SciTech Connect

    Hidayati, Dewi; Sulaiman, Norela; Othman, Shuhaimi; Ismail, B. S.

    2013-11-27

    Fish scale has the potential to be a rapid biomarker due to its structure and high possibility to come into contact with any pollutant in the aquatic environment. The scale structure consists of osteoblastic cells and other bone materials such as collagen where it is possible to form a molecular complex with heavy metals such as aluminum and iron. Hence, aluminum and iron in water could possibly destroy the scale material and marked as a scale deformation that quantitatively could be analyzed by comparing it to the normal scale structure. Water sampling and fish cage experiment were performed between June and July 2011 in Porong river which represented the water body that has high aluminum and iron contamination. The filtered water samples were preserved and extracted using the acid-mixture procedure prior to measurement of the aluminum and iron concentrations using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), while samples for total suspended solid (TSS) analysis were kept at 4 °C in cool-boxes. The scales were cleaned with sterile water, then dehydrated in 30, 50, 70, and 90% ethanol and dried on filter papers. They were then mounted on an aluminum stub and coated with gold in a sputter coater prior to Scanning Electron Microscope (SEM) observation. According to the SEM analysis, it was found that there were several deformations on the scale samples taken from sites that have high concentrations of aluminum and iron i.e. the increasing number of pits, deformation and decreasing number of spherules and ridges while the control scale exhibited the normal features. However, the site with higher TSS and pH indicated lower aluminum effect. A moderate correlation was found between the number of pits with aluminum (r=0.43) and iron (r=0.41) concentrations. Fish scale deformation using SEM analysis can potentially be a rapid biomarker in aquatic monitoring of aluminum and iron contamination. However, the measurement must be accompanied by pH and

  11. Net ammonium and nitrate fluxes in wheat roots under different environmental conditions as assessed by scanning ion-selective electrode technique.

    PubMed

    Zhong, Yangquanwei; Yan, Weiming; Chen, Juan; Shangguan, Zhouping

    2014-11-27

    Wheat is one of the most important food crops in the world, its availability affects global food security. In this study, we investigated variations in NH4(+) and NO3(-) fluxes in the fine roots of wheat using a scanning ion-selective electrode technique in the presence of different nitrogen (N) forms, N concentrations, and pH levels as well as under water stress. Our results show that the fine roots of wheat demonstrated maximum NH4(+) and NO3(-) influxes at 20 mm and 25 mm from the root tip, respectively. The maximal net NH4(+) and NO3(-) influxes were observed at pH 6.2 in the presence of a 1/4 N solution. We observed N efflux in two different cultivars following the exposure of roots to a 10% PEG-6000 solution. Furthermore, the drought-tolerant cultivar generally performed better than the drought-intolerant cultivar. Net NH4(+) and NO3(-) fluxes may be determined by plant growth status, but environmental conditions can also affect the magnitude and direction of N flux. Interestingly, we found that NO3(-) was more sensitive to environmental changes than NH4(+). Our results may be used to guide future hydroponic experiments in wheat as well as to aid in the development of effective fertilisation protocols for this crop.

  12. Net ammonium and nitrate fluxes in wheat roots under different environmental conditions as assessed by scanning ion-selective electrode technique

    PubMed Central

    Zhong, Yangquanwei; Yan, Weiming; Chen, Juan; Shangguan, Zhouping

    2014-01-01

    Wheat is one of the most important food crops in the world, its availability affects global food security. In this study, we investigated variations in NH4+ and NO3- fluxes in the fine roots of wheat using a scanning ion-selective electrode technique in the presence of different nitrogen (N) forms, N concentrations, and pH levels as well as under water stress. Our results show that the fine roots of wheat demonstrated maximum NH4+ and NO3− influxes at 20 mm and 25 mm from the root tip, respectively. The maximal net NH4+ and NO3− influxes were observed at pH 6.2 in the presence of a 1/4 N solution. We observed N efflux in two different cultivars following the exposure of roots to a 10% PEG-6000 solution. Furthermore, the drought-tolerant cultivar generally performed better than the drought-intolerant cultivar. Net NH4+ and NO3− fluxes may be determined by plant growth status, but environmental conditions can also affect the magnitude and direction of N flux. Interestingly, we found that NO3− was more sensitive to environmental changes than NH4+. Our results may be used to guide future hydroponic experiments in wheat as well as to aid in the development of effective fertilisation protocols for this crop. PMID:25428199

  13. High-quality imaging in environmental scanning electron microscopy--optimizing the pressure limiting system and the secondary electron detection of a commercially available ESEM.

    PubMed

    Fitzek, H; Schroettner, H; Wagner, J; Hofer, F; Rattenberger, J

    2016-04-01

    In environmental scanning electron microscopy applications in the kPa regime are of increasing interest for the investigation of wet and biological samples, because neither sample preparation nor extensive cooling are necessary. Unfortunately, the applications are limited by poor image quality. In this work the image quality at high pressures of a FEI Quanta 600 (field emission gun) and a FEI Quanta 200 (thermionic gun) is greatly improved by optimizing the pressure limiting system and the secondary electron (SE) detection system. The scattering of the primary electron beam strongly increases with pressure and thus the image quality vanishes. The key to high-image quality at high pressures is to reduce scattering as far as possible while maintaining ideal operation conditions for the SE-detector. The amount of scattering is reduced by reducing both the additional stagnation gas thickness (aSGT) and the environmental distance (ED). A new aperture holder is presented that significantly reduces the aSGT while maintaining the same field-of-view (FOV) as the original design. With this aperture holder it is also possible to make the aSGT even smaller at the expense of a smaller FOV. A new blade-shaped SE-detector is presented yielding better image quality than usual flat SE-detectors. The electrode of the new SE detector is positioned on the sample table, which allows the SE-detector to operate at ideal conditions regardless of pressure and ED.

  14. Individual Cell Based Traits Obtained by Scanning Flow-Cytometry Show Selection by Biotic and Abiotic Environmental Factors during a Phytoplankton Spring Bloom

    PubMed Central

    Pomati, Francesco; Kraft, Nathan J. B.; Posch, Thomas; Eugster, Bettina; Jokela, Jukka; Ibelings, Bas W.

    2013-01-01

    In ecology and evolution, the primary challenge in understanding the processes that shape biodiversity is to assess the relationship between the phenotypic traits of organisms and the environment. Here we tested for selection on physio-morphological traits measured by scanning flow-cytometry at the individual level in phytoplankton communities under a temporally changing biotic and abiotic environment. Our aim was to study how high-frequency temporal changes in the environment influence biodiversity dynamics in a natural community. We focused on a spring bloom in Lake Zurich (Switzerland), characterized by rapid changes in phytoplankton, water conditions, nutrients and grazing (mainly mediated by herbivore ciliates). We described bloom dynamics in terms of taxonomic and trait-based diversity and found that diversity dynamics of trait-based groups were more pronounced than those of identified phytoplankton taxa. We characterized the linkage between measured phytoplankton traits, abiotic environmental factors and abundance of the main grazers and observed weak but significant correlations between changing abiotic and biotic conditions and measured size-related and fluorescence-related traits. We tested for deviations in observed community-wide distributions of focal traits from random patterns and found evidence for both clustering and even spacing of traits, occurring sporadically over the time series. Patterns were consistent with environmental filtering and phenotypic divergence under herbivore pressure, respectively. Size-related traits showed significant even spacing during the peak of herbivore abundance, suggesting that morphology-related traits were under selection from grazing. Pigment distribution within cells and colonies appeared instead to be associated with acclimation to temperature and water chemistry. We found support for trade-offs among grazing resistance and environmental tolerance traits, as well as for substantial periods of dynamics in which

  15. CT Scans

    MedlinePlus

    ... cross-sectional pictures of your body. Doctors use CT scans to look for Broken bones Cancers Blood clots Signs of heart disease Internal bleeding During a CT scan, you lie still on a table. The table ...

  16. Serious Choices: A Protocol for an Environmental Scan of Patient Decision Aids for Seriously Ill People at Risk of Death Facing Choices about Life-Sustaining Treatments.

    PubMed

    Saunders, Catherine H; Elwyn, Glyn; Kirkland, Kathryn; Durand, Marie-Anne

    2017-08-20

    Seriously ill people at high risk of death face difficult decisions, especially concerning the extent of medical intervention. Given the inherent difficulty and complexity of these decisions, the care they receive often does not align with their preferences. Patient decision aids that educate individuals about options and help them construct preferences about life-sustaining care may reduce the mismatch between the care people say they want and the care they receive. The quantity and quality of patient decision aids for those at high risk of death, however, are unknown. This protocol describes an approach for conducting an environmental scan of life-sustaining treatment patient decision aids for seriously ill patients, identified online and through informant analysis. We intend for the outcome to be an inventory of all life-sustaining treatment patient decision aids for seriously ill patients currently available (either publicly or proprietarily) along with information about their content, quality, and known use. We will identify patient decision aids in a three-step approach (1) mining previously published systematic reviews; (2) systematically searching online and in two popular app stores; and (3) undertaking a key informant survey. We will screen and assess the quality of each patient decision aid identified using the latest published draft of the U.S. National Quality Forum National Standards for the Certification of Patient Decision Aids. Additionally, we will evaluate readability via readable.io and content via inductive content analysis. We will also use natural language processing to assess the content of the decision aids. Researchers increasingly recognize the environmental scan as an optimal method for studying real-world interventions, such as patient decision aids. This study will advance our understanding of the availability, quality, and use of decision aids for life-sustaining interventions targeted at seriously ill patients. We also aim to provide

  17. The Scanning Process: Getting Started.

    ERIC Educational Resources Information Center

    Renfro, William L.; Morrison, James L.

    1983-01-01

    Scanning the external environment will become more essential to colleges in the coming decade. Developing an environmental scanning system can identify important emerging issues that may constitute either threats or opportunities. The organizational features of a mature scanning process are described. (MLW)

  18. Morphology, Spatial Distribution, and Concentration of Flame Retardants in Consumer Products and Environmental Dusts using Scanning Electron Microscopy and Raman Micro-spectroscopy

    PubMed Central

    WAGNER, JEFF; GHOSAL, SUTAPA; WHITEHEAD, TODD; METAYER, CATHERINE

    2013-01-01

    We characterized flame retardant (FR) morphologies and spatial distributions in 7 consumer products and 7 environmental dusts to determine their implications for transfer mechanisms, human exposure, and the reproducibility of gas chromatography-mass spectrometry (GC-MS) dust measurements. We characterized individual particles using scanning electron microscopy / energy dispersive x-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS). Samples were screened for the presence of 3 FR constituents (bromine, phosphorous, non-salt chlorine) and 2 metal synergists (antimony and bismuth). Subsequent analyses of select samples by RMS enabled molecular identification of the FR compounds and matrix materials. The consumer products and dust samples possessed FR elemental weight percents of up to 36% and 31%, respectively. We identified 24 FR-containing particles in the dust samples and classified them into 9 types based on morphology and composition. We observed a broad range of morphologies for these FR-containing particles, suggesting FR transfer to dust via multiple mechanisms. We developed an equation to describe the heterogeneity of FR-containing particles in environmental dust samples. The number of individual FR-containing particles expected in a 1-mg dust sample with a FR concentration of 100 ppm ranged from <1 to >1000 particles. The presence of rare, high-concentration bromine particles was correlated with decabromodiphenyl ether concentrations obtained via GC-MS. When FRs are distributed heterogeneously in highly concentrated dust particles, human exposure to FRs may be characterized by high transient exposures interspersed by periods of low exposure, and GC-MS FR concentrations may exhibit large variability in replicate subsamples. Current limitations of this SEM/EDS technique include potential false negatives for volatile and chlorinated FRs and greater quantitation uncertainty for brominated FR in aluminum-rich matrices. PMID:23739093

  19. Scanning SQUID microscopy of a ferromanganese crust from the northwestern Pacific: Submillimeter scale magnetostratigraphy as a new tool for age determination and mapping of environmental magnetic parameters

    NASA Astrophysics Data System (ADS)

    Noguchi, A.; Oda, H.; Yamamoto, Y.; Usui, A.; Sato, M.; Kawai, J.

    2017-06-01

    Ferromanganese crusts record long-term deep-sea environmental changes. Thus, providing their reliable high-resolution age models is important. We applied a magnetostratigraphic technique to estimate the growth rate of a ferromanganese crust using scanning SQUID (superconducting quantum interference device) microscope (SSM). SSM is designed to map the magnetic field across thin sections with submillimeter resolution. The crust sample was taken from the Takuyo-Daigo Seamount, northwestern Pacific, and recorded a limited supply of dust and sediment from continents. After drift correction and removal of spike noises, the magnetic field values were stacked within the areas of high signal-to-noise ratios. By correlating the obtained profiles with a standard geomagnetic polarity timescale, we obtained an average growth rate of 3.37 ± 0.06 mm/Ma, which is consistent with that obtained by 10Be/9Be geochronology (2.93 ± 0.15 mm/Ma). S ratio mapping shows low values after 3 Ma, associated with voids between columnar structures.

  20. Environmental Scanning Electron Microscopy characterization of the adhesion of conidia from Penicillium expansum to cedar wood substrata at different pH values.

    PubMed

    El Abed, Soumya; Ibnsouda, Saad Koraichi; Latrache, Hassan; Meftah, Hasna; Tahri, Nezha Joutey; Hamadi, Fatima

    2012-04-01

    Initial microbial adhesion to surfaces is a complicated process that is affected by a number of factors. An important property of a solution that may influence adhesion is pH. The surface properties of the cedar wood were characterized by the sessile drop technique. Moreover, the interfacial free energy of surface adhesion to the cedar wood was determined under pH values (2, 3, 5, 7, 9 and 11). The results showed that cedar wood examined at different pH levels could be considered hydrophobic ranged from Giwi = -13.1 mJ/m(2) to Giwi = -75 mJ/m(2). We noted that the electron-donor character of cedar wood was important at both basic and limit acidic conditions (pH 11 and pH 3) and it decreased at intermediate pH (pH 5). The cedar wood substratum presents a weak electron acceptor under various pH's. In addition, the adhesion of conidia from Penicilllium expansum to the cedar wood surfaces at different pH values (2, 3, 5, 7, 9 and 11) was investigated using Environmental Scanning Electron Microscopy and image analysis was assessed with the Mathlab(®) program. The data analysis showed that the conidia from P. expansum were strongly influenced by the pH. The maximum adhesion occurs in the pH 11 and pH 3 and decreased to 24% at pH 5.

  1. New insight in understanding oxygen reduction and evolution in solid-state lithium-oxygen batteries using an in situ environmental scanning electron microscope.

    PubMed

    Zheng, Hao; Xiao, Dongdong; Li, Xing; Liu, Yali; Wu, Yang; Wang, Jiaping; Jiang, Kaili; Chen, Chun; Gu, Lin; Wei, Xianlong; Hu, Yong-Sheng; Chen, Qing; Li, Hong

    2014-08-13

    Via designing a facile microscale all-solid-state lithium-oxygen battery system constructed in an environmental scanning electron microscope, direct visualization of discharge and charge processes of the lithium-oxygen battery is achieved. Different morphologies of the discharge product are observed, including a sphere, conformal film, and red-blood-cell-like shape, with a particle size up to 1.5 μm; whereas upon charge, the decomposition initiates at their surface and continues along a certain direction, instead of from the contact point at the electrode. These new findings indicate that the electron and lithium ion conductivities of Li2O2 could support the growth and decomposition of the discharge product in our system. In addition, our results indicate that various morphologies of Li2O2 arise from the different current density and surface chemistry of CNT, and the growth and decomposition of the particle are related to the uneven distribution of the ionic and electronic conductivities of Li2O2.

  2. Environmental, scanning electron and optical microscope image analysis software for determining volume and occupied area of solid-state fermentation fungal cultures.

    PubMed

    Osma, Johann F; Toca-Herrera, José L; Rodríguez-Couto, Susana

    2011-01-01

    Here we propose a software for the estimation of the occupied area and volume of fungal cultures. This software was developed using a Matlab platform and allows analysis of high-definition images from optical, electronic or atomic force microscopes. In a first step, a single hypha grown on potato dextrose agar was monitored using optical microscopy to estimate the change in occupied area and volume. Weight measurements were carried out to compare them with the estimated volume, revealing a slight difference of less than 1.5%. Similarly, samples from two different solid-state fermentation cultures were analyzed using images from a scanning electron microscope (SEM) and an environmental SEM (ESEM). Occupied area and volume were calculated for both samples, and the results obtained were correlated with the dry weight of the cultures. The difference between the estimated volume ratio and the dry weight ratio of the two cultures showed a difference of 10%. Therefore, this software is a promising non-invasive technique to determine fungal biomass in solid-state cultures.

  3. Macrophages and dendritic cells in the rat meninges and choroid plexus: three-dimensional localisation by environmental scanning electron microscopy and confocal microscopy.

    PubMed

    McMenamin, Paul G; Wealthall, Rosamund J; Deverall, Marie; Cooper, Stephanie J; Griffin, Brendan

    2003-09-01

    The present investigation provides novel information on the topographical distribution of macrophages and dendritic cells (DCs) in normal meninges and choroid plexus of the rat central nervous system (CNS). Whole-mounts of meninges and choroid plexus of Lewis rats were incubated with various anti-leucocyte monoclonal antibodies and either visualised with gold-conjugated secondary antibody followed by silver enhancement and subsequent examination by environmental scanning electron microscopy or by the use of fluorochromes and confocal microscopy. Large numbers of MHC class II(+) putative DCs were identified on the internal or subarachnoid aspect of dural whole-mounts, on the surface of the cortex (pia/arachnoid) and on the surface of the choroid plexus. Occupation of these sites would allow DCs access to cerebrospinal fluid (CSF) and therefore allow antigens into the subarachnoid space and ventricles. By contrast, macrophages were less evident at sites exposed to CSF and were more frequently located within the connective tissue of the dura/arachnoid and choroid plexus stroma and also in a sub-pial location. The present data suggest that DC may be strategically located within the CNS to sample CSF-borne antigens. Furthermore, the data suggest that CNS tissue samples collected without careful removal of the meninges may inadvertently be contaminated by DCs and meningeal macrophages.

  4. Environmental scan of infection prevention and control practices for containment of hospital-acquired infectious disease outbreaks in acute care hospital settings across Canada.

    PubMed

    Ocampo, Wrechelle; Geransar, Rose; Clayden, Nancy; Jones, Jessica; de Grood, Jill; Joffe, Mark; Taylor, Geoffrey; Missaghi, Bayan; Pearce, Craig; Ghali, William; Conly, John

    2017-07-18

    Ward closure is a method of controlling hospital-acquired infectious diseases outbreaks and is often coupled with other practices. However, the value and efficacy of ward closures remains uncertain. To understand the current practices and perceptions with respect to ward closure for hospital-acquired infectious disease outbreaks in acute care hospital settings across Canada. A Web-based environmental scan survey was developed by a team of infection prevention and control (IPC) experts and distributed to 235 IPC professionals at acute care sites across Canada. Data were analyzed using a mixed-methods approach of descriptive statistics and thematic analysis. A total of 110 completed responses showed that 70% of sites reported at least 1 outbreak during 2013, 44% of these sites reported the use of ward closure. Ward closure was considered an "appropriate," "sometimes appropriate," or "not appropriate" strategy to control outbreaks by 50%, 45%, and 5% of participants, respectively. System capacity issues and overall risk assessment were main factors influencing the decision to close hospital wards following an outbreak. Results suggest the use of ward closure for containment of hospital-acquired infectious disease outbreaks in Canadian acute care health settings is mixed, with outbreak control methods varying. The successful implementation of ward closure was dependent on overall support for the IPC team within hospital administration. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  5. Renal scan

    MedlinePlus

    ... and urinate often to help remove the radioactive material from the body. How to Prepare for the Test Tell your health care provider if you take ... drink additional fluids before the scan. How the Test will ... into the vein. However, you will not feel the radioactive material. The scanning table may be hard and cold. ...

  6. Environmental factors controlling the distribution of rhodoliths: An integrated study based on seafloor sampling, ROV and side scan sonar data, offshore the W-Pontine Archipelago

    NASA Astrophysics Data System (ADS)

    Sañé, E.; Chiocci, F. L.; Basso, D.; Martorelli, E.

    2016-10-01

    The effects of different environmental factors controlling the distribution of different morphologies, sizes and growth forms of rhodoliths in the western Pontine Archipelago have been studied. The analysis of 231 grab samples has been integrated with 68 remotely operated vehicle (ROV) videos (22 h) and a high resolution (<1 m) side scan sonar mosaic of the seafloor surrounding the Archipelago, covering an area of approximately 460 km2. Living rhodoliths were collected in approximately 10% of the grab samples and observed in approximately 30% of the ROV dives. The combination of sediment sampling, video surveys and acoustic facies mapping suggested that the presence of rhodoliths can be associated to the dishomogeneous high backscatter sonar facies and high backscatter facies. Both pralines and unattached branches were found to be the most abundant morphological groups (50% and 41% of samples, respectively), whereas boxwork rhodoliths were less common, accounting only for less than 10% of the total number of samples. Pralines and boxwork rhodoliths were almost equally distributed among large (28%), medium (36%) and small sizes (36%). Pralines generally presented a fruticose growth form (49% of pralines) even if pralines with encrusting-warty (36% of pralines) or lumpy (15% of pralines) growth forms were also present. Morphologies, sizes and growth forms vary mainly along the depth gradient. Large rhodoliths with a boxwork morphology are abundant at depth, whereas unattached branches and, in general, rhodoliths with a high protuberance degree are abundant in shallow waters. The exposure to storm waves and bottom currents related to geostrofic circulation could explain the absence of rhodoliths off the eastern side of the three islands forming the Archipelago.

  7. Recycling stainless steel orthodontic brackets with Er:YAG laser – An environmental scanning electron microscope and shear bond strength study

    PubMed Central

    Chacko, Prince K; Kodoth, Jithesh; John, Jacob; Kumar, Kishore

    2013-01-01

    Aim: To determine the efficiency of erbium: Yttrium aluminum garnet (Er:YAG) laser with Environmental Scanning Electron Microscope (ESEM) and shear bond strength analysis as a method of recycling stainless steel orthodontic brackets and compare with other methods of recycling. Materials and Methods: Eighty samples of extracted premolar teeth bonded to SS brackets were tested for rebonded shear bond strength after recycling by four methods and compared with a control group of 20 samples. These 80 samples were randomized into four groups which were recycled by four methods, namely, sandblasting, thermal method, adhesive grinding by tungsten carbide bur, and Er: YAG laser method. After recycling, ESEM and shear bond strength analysis were used to analyze the efficiency of the recycling methods Results: Er: YAG laser group was found to be having the greatest bond strength among the recycled brackets (8.33±2.51 followed by the sandblasting at 6.12±1.12 MPa, thermal and electropolishing at 4.44±0.95 MPa, and lastly the adhesive grinding method at 3.08±1.07 MPa. The shear bond strength of Er: YAG laser group was found to be having no statistically significant difference with that of the control group (P>0.05 and had statistical signifance with sandblasting, thermal and electropolishing and adhesive grinding groups at P>0.001. ESEM analysis showed complete removal of adhesive from the brackets recycled with Er: YAG laser which mimicked that of the control group. Conclusion: Er: YAG laser (2940 nm) was found to be the most efficient method for recycling, followed by the sandblasting, thermal, and the tungsten carbide methods, which had the least shear bond strength value and is not fit for clinical usage. PMID:24987647

  8. Group 13 allergens as environmental and immunological markers for grass pollen allergy: studies by immunogold field emission scanning and transmission electron microscopy.

    PubMed

    Grote, Monika; Swoboda, Ines; Valenta, Rudolf; Reichelt, Rudolf

    2005-04-01

    Polygalacturonases were recently identified as important grass pollen allergens and designated group 13 allergens. The objective of the present study was to investigate the presence of group 13 grass pollen allergens in different grass species, their release and ultrastructural location in dry and hydrated grass pollen. Nitrocellulose-blotted allergen extracts from 12 wild and cultivated grass genera were probed with a rabbit antiserum raised against purified recombinant timothy grass pollen allergen, Phl p 13. The release kinetics of Phl p 13 from timothy grass pollen hydrated for 0.5 min to 3 h were analyzed by immunoblotting. Phl p 13 was localized in dry and hydrated grass pollen grains by immunogold field emission scanning and transmission electron microscopy. Group 13 allergens were detected in all 12 wild and cultivated grass genera representing the major subfamilies of the Poaceae. Ultrastructurally, the allergen was located in the wall and in the cytoplasm of timothy grass pollen grains. In the cytoplasm, Phl p 13 was associated with polysaccharide particles and as yet undescribed stacks of microtubule-like structures. After hydration in rain water, pollen grains expel cytoplasmic particles of respirable size containing Phl p 13, which becomes detectable in aqueous supernatants already after 0.5 min. Group 13 allergens represent one set of marker allergens which specifically occur in pollen of the major grass subfamilies and are rapidly released in association with respirable particles after pollen hydration. They may be considered as environmental markers for grass pollen exposure and group 13-specific IgE antibodies as immunological markers for genuine grass pollen sensitization. Copyright (c) 2005 S. Karger AG, Basel

  9. Thyroid scan

    MedlinePlus

    ... rays given off by the radioactive material. A computer displays images of the thyroid gland. Other scans ... It is an even gray color on the computer image without darker or lighter areas. What Abnormal ...

  10. Gallium scan

    MedlinePlus

    ... material called gallium and is a type of nuclear medicine exam. A related test is gallium scan ... Brown ML, Forstrom LA, et al. Society of nuclear medicine procedure guideline for gallium scintigraphy in inflammation. ...

  11. Liver scan

    MedlinePlus

    ... cirrhosis or hepatitis ) Superior vena cava obstruction Splenic infarction (tissue death) Tumors Risks Radiation from any scan ... Hepatitis Liver cancer - hepatocellular carcinoma Liver disease Splenic infarction SVC obstruction Review Date 1/18/2015 Updated ...

  12. 3D Micro-topography of Transferred Laboratory and Natural Ice Crystal Surfaces Imaged by Cryo and Environmental Scanning Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Magee, N. B.; Boaggio, K.; Bancroft, L.; Bandamede, M.

    2015-12-01

    Recent work has highlighted micro-scale roughness on the surfaces of ice crystals grown and imaged in-situ within the chambers of environmental scanning electron microscopes (ESEM). These observations appear to align with theoretical and satellite observations that suggest a prevalence of rough ice in cirrus clouds. However, the atmospheric application of the lab observations are indeterminate because the observations have been based only on crystals grown on substrates and in pure-water vapor environments. In this work, we present details and results from the development of a transfer technique which allows natural and lab-grown ice and snow crystals to be captured, preserved, and transferred into the ESEM for 3D imaging. Ice crystals were gathered from 1) natural snow, 2) a balloon-borne cirrus particle capture device, and 3) lab-grown ice crystals from a diffusion chamber. Ice crystals were captured in a pre-conditioned small-volume (~1 cm3) cryo-containment cell. The cell was then sealed closed and transferred to a specially-designed cryogenic dewer (filled with liquid nitrogen or crushed dry ice) for transport to a new Hitachi Field Emission, Variable Pressure SEM (SU-5000). The cryo-cell was then removed from the dewer and quickly placed onto the pre-conditioned cryo transfer stage attached to the ESEM (Quorum 3010T). Quantitative 3D topographical digital elevation models of ice surfaces are reported from SEM for the first time, including a variety of objective measures of statistical surface roughness. The surfaces of the transported crystals clearly exhibit signatures of mesoscopic roughening that are similar to examples of roughness seen in ESEM-grown crystals. For most transported crystals, the habits and crystal edges are more intricate that those observed for ice grown directly on substrates within the ESEM chamber. Portions of some crystals do appear smooth even at magnification greater than 1000x, a rare observation in our ESEM-grown crystals. The

  13. Head CT scan

    MedlinePlus

    Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... conditions: Birth (congenital) defect of the head or brain Brain infection Brain tumor Buildup of fluid inside ...

  14. Absolute distance measurement system with micron-grade measurement uncertainty and 24 m range using frequency scanning interferometry with compensation of environmental vibration.

    PubMed

    Lu, Cheng; Liu, Guodong; Liu, Bingguo; Chen, Fengdong; Gan, Yu

    2016-12-26

    We establish a theoretical model of the Doppler effect in absolute distance measurements using frequency scanning interferometry (FSI) and propose a novel FSI absolute distance measurement system. This system incorporates a basic FSI system and a laser Doppler velocimeter (LDV). The LDV results are used to correct for the Doppler effect in the absolute distance measurement signal obtained by the basic FSI system. In the measurement of a target located at 16 m, a measurement resolution of 65.5 μm is obtained, which is close to the theoretical resolution, and a standard deviation of 3.15 μm is obtained. The theoretical measurement uncertainty is 8.6 μm + 0.16 μm/m Rm (k = 2) within a distance range of 1 m to 24 m neglecting the influence of air refractive index, which has been verified with experiments.

  15. Comparison of data from the Scanning Multifrequency Microwave Radiometer (SMMR) with data from the Advanced Very High Resolution Radiometer (AVHRR) for terrestrial environmental monitoring - An overview

    NASA Technical Reports Server (NTRS)

    Townshend, J. R. G.; Choudhury, B. J.; Tucker, C. J.; Giddings, L.; Justice, C. O.

    1989-01-01

    Comparison between the microwave polarized difference temperature (MPDT) derived from 37 GHz band data and the normalized difference vegetation index (NDVI) derived from near-infrared and red bands, from several empirical investigations are summarized. These indicate the complementary character of the two measures in environmental monitoring. Overall the NDVI is more sensitive to green leaf activity, whereas the MPDT appears also to be related to other elements of the above-ground biomass. Monitoring of hydrological phenomena is carried out much more effectively by the MPDT. Further work is needed to explain spectral and temporal variation in MPDT both through modelling and field experiments.

  16. Comparison of data from the Scanning Multifrequency Microwave Radiometer (SMMR) with data from the Advanced Very High Resolution Radiometer (AVHRR) for terrestrial environmental monitoring - An overview

    NASA Technical Reports Server (NTRS)

    Townshend, J. R. G.; Choudhury, B. J.; Tucker, C. J.; Giddings, L.; Justice, C. O.

    1989-01-01

    Comparison between the microwave polarized difference temperature (MPDT) derived from 37 GHz band data and the normalized difference vegetation index (NDVI) derived from near-infrared and red bands, from several empirical investigations are summarized. These indicate the complementary character of the two measures in environmental monitoring. Overall the NDVI is more sensitive to green leaf activity, whereas the MPDT appears also to be related to other elements of the above-ground biomass. Monitoring of hydrological phenomena is carried out much more effectively by the MPDT. Further work is needed to explain spectral and temporal variation in MPDT both through modelling and field experiments.

  17. Correlated Raman micro-spectroscopy and scanning electron microscopy analyses of flame retardants in environmental samples: a micro-analytical tool for probing chemical composition, origin and spatial distribution.

    PubMed

    Ghosal, Sutapa; Wagner, Jeff

    2013-07-07

    We present correlated application of two micro-analytical techniques: scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS) for the non-invasive characterization and molecular identification of flame retardants (FRs) in environmental dusts and consumer products. The SEM/EDS-RMS technique offers correlated, morphological, molecular, spatial distribution and semi-quantitative elemental concentration information at the individual particle level with micrometer spatial resolution and minimal sample preparation. The presented methodology uses SEM/EDS analyses for rapid detection of particles containing FR specific elements as potential indicators of FR presence in a sample followed by correlated RMS analyses of the same particles for characterization of the FR sub-regions and surrounding matrices. The spatially resolved characterization enabled by this approach provides insights into the distributional heterogeneity as well as potential transfer and exposure mechanisms for FRs in the environment that is typically not available through traditional FR analysis. We have used this methodology to reveal a heterogeneous distribution of highly concentrated deca-BDE particles in environmental dust, sometimes in association with identifiable consumer materials. The observed coexistence of deca-BDE with consumer material in dust is strongly indicative of its release into the environment via weathering/abrasion of consumer products. Ingestion of such enriched FR particles in dust represents a potential for instantaneous exposure to high FR concentrations. Therefore, correlated SEM/RMS analysis offers a novel investigative tool for addressing an area of important environmental concern.

  18. Chemical Imaging Analysis of Environmental Particles Using the Focused Ion Beam/Scanning Electron Microscopy Technique. Microanalysis Insights into Atmospheric Chemistry of Fly Ash

    SciTech Connect

    Chen, Haihan; Grassian, Vicki H.; Saraf, Laxmikant V.; Laskin, Alexander

    2012-11-08

    Airborne fly ash from coal combustion may represent a source of bioavailable iron (Fe) in the open ocean. However, few studies have been made focusing on Fe speciation and distribution in coal fly ash. In this study, chemical imaging of fly ash has been performed using a dual-beam FIB/SEM (focused ion beam/scanning electron microscope) system for a better understanding of how simulated atmospheric processing modify the morphology, chemical compositions and element distributions of individual particles. A novel approach has been applied for cross-sectioning of fly ash specimen with a FIB in order to explore element distribution within the interior of individual particles. Our results indicate that simulated atmospheric processing causes disintegration of aluminosilicate glass, a dominant material in fly ash particles. Aluminosilicate-phase Fe in the inner core of fly ash particles is more easily mobilized compared with oxide-phase Fe present as surface aggregates on fly ash spheres. Fe release behavior depends strongly on Fe speciation in aerosol particles. The approach for preparation of cross-sectioned specimen described here opens new opportunities for particle microanalysis, particular with respect to inorganic refractive materials like fly ash and mineral dust.

  19. External Scan 2000: Environmental Scan of the Greater Sacramento Area.

    ERIC Educational Resources Information Center

    Beachler, Judith

    This document provides a summary of the social, economic, and political changes at state and national levels that affect the Los Rios Community College District (LRCCD) in California. LRCCD consists of American River College (ARC), Cosumnes River College (CRC), and Sacramento City College (SCC). Demographic trends show that Greater Sacramento is…

  20. Arm CT scan

    MedlinePlus

    CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... your provider should weigh this risk against the benefits of getting a correct diagnosis for a medical ...

  1. Scanning ultrafast electron microscopy.

    PubMed

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

    2010-08-24

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

  2. Scanning ultrafast electron microscopy

    PubMed Central

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

    2010-01-01

    Progress has been made in the development of four-dimensional ultrafast electron microscopy, which enables space-time imaging of structural dynamics in the condensed phase. In ultrafast electron microscopy, the electrons are accelerated, typically to 200 keV, and the microscope operates in the transmission mode. Here, we report the development of scanning ultrafast electron microscopy using a field-emission-source configuration. Scanning of pulses is made in the single-electron mode, for which the pulse contains at most one or a few electrons, thus achieving imaging without the space-charge effect between electrons, and still in ten(s) of seconds. For imaging, the secondary electrons from surface structures are detected, as demonstrated here for material surfaces and biological specimens. By recording backscattered electrons, diffraction patterns from single crystals were also obtained. Scanning pulsed-electron microscopy with the acquired spatiotemporal resolutions, and its efficient heat-dissipation feature, is now poised to provide in situ 4D imaging and with environmental capability. PMID:20696933

  3. Dynamic scan control in STEM: Spiral scans

    DOE PAGES

    Lupini, Andrew R.; Borisevich, Albina Y.; Kalinin, Sergei V.; ...

    2016-06-13

    Here, scanning transmission electron microscopy (STEM) has emerged as one of the foremost techniques to analyze materials at atomic resolution. However, two practical difficulties inherent to STEM imaging are: radiation damage imparted by the electron beam, which can potentially damage or otherwise modify the specimen and slow-scan image acquisition, which limits the ability to capture dynamic changes at high temporal resolution. Furthermore, due in part to scan flyback corrections, typical raster scan methods result in an uneven distribution of dose across the scanned area. A method to allow extremely fast scanning with a uniform residence time would enable imaging atmore » low electron doses, ameliorating radiation damage and at the same time permitting image acquisition at higher frame-rates while maintaining atomic resolution. The practical complication is that rastering the STEM probe at higher speeds causes significant image distortions. Non-square scan patterns provide a solution to this dilemma and can be tailored for low dose imaging conditions. Here, we develop a method for imaging with alternative scan patterns and investigate their performance at very high scan speeds. A general analysis for spiral scanning is presented here for the following spiral scan functions: Archimedean, Fermat, and constant linear velocity spirals, which were tested for STEM imaging. The quality of spiral scan STEM images is generally comparable with STEM images from conventional raster scans, and the dose uniformity can be improved.« less

  4. Gallbladder radionuclide scan

    MedlinePlus

    Radionuclide - gallbladder; Gallbladder scan; Biliary scan; Cholescintigraphy; HIDA; Hepatobiliary nuclear imaging scan ... It will then flow with bile into the gallbladder and then the duodenum or small intestine. For ...

  5. SETAC launches global horizon scanning/research prioritization project

    EPA Science Inventory

    The SETAC World Council is pleased to announce the initiation of a Global Horizon Scanning and Prioritization Project aimed at identifying geographically specific research needs to address stressor impacts on environmental quality. In recent years, horizon scanning and research ...

  6. SETAC launches global horizon scanning/research prioritization project

    EPA Science Inventory

    The SETAC World Council is pleased to announce the initiation of a Global Horizon Scanning and Prioritization Project aimed at identifying geographically specific research needs to address stressor impacts on environmental quality. In recent years, horizon scanning and research ...

  7. An Environmental Scan of Northern Alameda County.

    ERIC Educational Resources Information Center

    Galloro, Nicholas

    A study was conducted to provide an overview of the demographic and economic characteristics of the geographical area served by the Peralta Community College District and to provide population and economic projections up to the year 2000. Historical data from the Alameda County Planning Commission, census data, and projections from the Association…

  8. Scanning the periphery.

    PubMed

    Day, George S; Schoemaker, Paul J H

    2005-11-01

    Companies often face new rivals, technologies, regulations, and other environmental changes that seem to come out of left field. How can they see these changes sooner and capitalize on them? Such changes often begin as weak signals on what the authors call the periphery, or the blurry zone at the edge of an organization's vision. As with human peripheral vision, these signals are difficult to see and interpret but can be vital to success or survival. Unfortunately, most companies lack a systematic method for determining where on the periphery they should be looking, how to interpret the weak signals they see, and how to allocate limited scanning resources. This article provides such a method-a question-based framework for helping companies scan the periphery more efficiently and effectively. The framework divides questions into three categories: learning from the past (What have been our past blind spots? What instructive analogies do other industries offer? Who in the industry is skilled at picking up weak signals and acting on them?); evaluating the present (What important signals are we rationalizing away? What are our mavericks, outliers, complainers, and defectors telling us? What are our peripheral customers and competitors really thinking?); and envisioning the future (What future surprises could really hurt or help us? What emerging technologies could change the game? Is there an unthinkable scenario that might disrupt our business?). Answering these questions is a good first step toward anticipating problems or opportunities that may appear on the business horizon. The article concludes with a self-test that companies can use to assess their need and capability for peripheral vision.

  9. CONFOCAL LASER SCANNING MICROSCOPY OF APOPTOSIS IN WHOLE MOUSE OVARIES

    EPA Science Inventory

    Confocal Laser Scanning Microscopy of Apoptosis in Whole Mouse Ovaries. Robert M. Zucker Susan C. Jeffay and Sally D. Perreault Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle...

  10. CONFOCAL LASER SCANNING MICROSCOPY OF APOPTOSIS IN WHOLE MOUSE OVARIES

    EPA Science Inventory

    Confocal Laser Scanning Microscopy of Apoptosis in Whole Mouse Ovaries. Robert M. Zucker Susan C. Jeffay and Sally D. Perreault Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle...

  11. RBC nuclear scan

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003835.htm RBC nuclear scan To use the sharing features on this page, please enable JavaScript. An RBC nuclear scan uses small amounts of radioactive material to ...

  12. Heart PET scan

    MedlinePlus

    Heart nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... Udelson JE, Dilsizian V, Bonow RO. Nuclear cardiology. In: Mann DL, ... A Textbook of Cardiovascular Medicine . 10th ed. Philadelphia, ...

  13. Abdominal CT scan

    MedlinePlus

    Computed tomography scan - abdomen; CT scan - abdomen; CT abdomen and pelvis ... 2016:chap 133. Radiologyinfo.org. Computed tomography (CT) - abdomen and pelvis. Updated June 16, 2016. www.radiologyinfo. ...

  14. Scanning mirror arrangement

    SciTech Connect

    Stetson, N.B.

    1982-08-31

    An image forming scanning mechanism without obturation in its optical path comprises first and second reflectors that are pivotally actuated about respective orthogonal axes. The scanning reflectors are positioned so that radiant energy in a first optical path from an object field impinges upon a vertical-scan reflector where it is directed to a horizontal-scan reflector and whereupon it is directed back onto the vertical-scan reflector from whence it is reflected along a second optical path in a different plane from the first optical path. The pivotal axes of the vertical-scan reflector and the horizontal-scan reflector are perpendicular to path of radiant energy reflected therefrom. A detector is positioned to receive radiant energy from elemental areas of an object field. The orthogonal disposition of the first and second pivotal axes provides a distortion free image signal from the detector that is comparable with the x-y scan pattern of conventional television display circuits.

  15. Bone density scan (image)

    MedlinePlus

    A bone density scan measures the density of bone in a person. The lower the density of a bone the ... and whether any preventative treatment is needed. A bone density scan has the advantage of being painless and ...

  16. Multipurpose binocular scanning apparatus

    NASA Technical Reports Server (NTRS)

    Chamberlain, F. R.; Parker, G. L.

    1969-01-01

    Optical gimballing apparatus directs narrow fields of view throughout solid angle approaching 4 pi steradians. Image rotation produced by scanning can be eliminated or altered by gear trains directly linked to the scanning drive assembly. It provides the basis for a binocular scanning capability.

  17. Scanning the Front Range Environment: A Statistical Snapshot of the Front Range Community College Service Area.

    ERIC Educational Resources Information Center

    Front Range Community Coll., Westminster, CO.

    This environmental scanning report from Front Range Community College (FRCC) in Colorado examines trends in population, demographics, income, and education in the college's service area. The report begins with Kathleen Cain's essay, "Environmental Scanning," indicating that the four major objectives of environmental scanning are to…

  18. Rapid frequency scan EPR.

    PubMed

    Tseitlin, Mark; Rinard, George A; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2011-08-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x, y plane decays to baseline at the end of the scan, which typically is about 5T(2) after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5T(2). However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded with a total scan period of 5T(2), even if some spins are excited later in the scan. This scan time is similar to polyphase excitation methods. The peak power required for either polyphase excitation or rapid frequency scans is substantially smaller than for pulsed EPR. The use of an arbitrary waveform generator (AWG) and cross loop resonator facilitated implementation of the rapid frequency scan experiments reported here. The use of constant continuous low B(1), periodic excitation waveform, and constant external magnetic field is similar to polyphase excitation, but could be implemented without the AWG that is required for polyphase excitation.

  19. Rapid Frequency Scan EPR

    PubMed Central

    Tseitlin, Mark; Rinard, George A.; Quine, Richard W.; Eaton, Sandra S.; Eaton, Gareth R.

    2011-01-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x,y plane decays to baseline at the end of the scan, which typically is about 5 T2 after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5 T2. However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded with a total scan period of 5 T2, even if some spins are excited later in the scan. This scan time is similar to polyphase excitation methods. The peak power required for either polyphase excitation or rapid frequency scans is substantially smaller than for pulsed EPR. The use of an arbitrary waveform generator (AWG) and cross loop resonator facilitated implementation of the rapid frequency scan experiments reported here. The use of constant continuous low B1, periodic excitation waveform, and constant external magnetic field is similar to polyphase excitation, but could be implemented without the AWG that is required for polyphase excitation. PMID:21664848

  20. Line-scanning, stage scanning confocal microscope

    NASA Astrophysics Data System (ADS)

    Carucci, John A.; Stevenson, Mary; Gareau, Daniel

    2016-03-01

    We created a line-scanning, stage scanning confocal microscope as part of a new procedure: video assisted micrographic surgery (VAMS). The need for rapid pathological assessment of the tissue on the surface of skin excisions very large since there are 3.5 million new skin cancers diagnosed annually in the United States. The new design presented here is a confocal microscope without any scanning optics. Instead, a line is focused in space and the sample, which is flattened, is physically translated such that the line scans across its face in a direction perpendicular to the line its self. The line is 6mm long and the stage is capable of scanning 50 mm, hence the field of view is quite large. The theoretical diffraction-limited resolution is 0.7um lateral and 3.7um axial. However, in this preliminary report, we present initial results that are a factor of 5-7 poorer in resolution. The results are encouraging because they demonstrate that the linear array detector measures sufficient signal from fluorescently labeled tissue and also demonstrate the large field of view achievable with VAMS.

  1. Environmental scanning electron microscopy connected with energy dispersive x-ray analysis and Raman techniques to study ProRoot mineral trioxide aggregate and calcium silicate cements in wet conditions and in real time.

    PubMed

    Gandolfi, Maria Giovanna; Van Landuyt, Kirsten; Taddei, Paola; Modena, Enrico; Van Meerbeek, Bart; Prati, Carlo

    2010-05-01

    ProRoot mineral trioxide aggregate (MTA) and calcium silicate cements are able to set in a moist environment. The aim of the study was to examine the surface structure and composition of a cement paste under wet conditions and in real time during setting by environmental scanning electron microscopy connected with energy dispersive x-ray analysis (ESEM-EDX) and micro-Raman techniques. White ProRoot MTA and experimental white tetrasilicate cement (wTC) and wTC containing bismuth oxide (wTC-Bi) were studied. Cement disks were analyzed 10 minutes after powder-liquid mixing (freshly prepared samples) and after immersion in Dulbecco phosphate-buffered saline at 37 degrees C for 24 hours (24-hour-aged samples). Freshly prepared wet cements at ESEM-EDX exposed an irregular surface (displaying calcium, silicon, aluminum, chlorine reflexes, and bismuth traces in MTA and wTC-Bi) with needle-like and cubic-hexagonal shaped crystals. Aggregates of spheroidal Ca-P-rich crystals (spherulites) appeared on the surface of 24-hour-aged samples. The starting unhydrated powders displayed the typical Raman bands of Portland cement components: alite, belite, and calcium sulfate (only as anhydrite in MTA and as both anhydrite and gypsum in wTC and wTC-Bi). MTA powder showed higher amount of calcium carbonate and lower quantities of anhydrite and higher crystallinity of the silicate component, leading to a slower hydration reaction. Products/markers of hydration reactions were present on fresh samples; ettringite formed on the surface of all the cements; calcium hydroxide (portlandite) was detected only on the surface of wTC, but no conclusion can be drawn on wTC-Bi and MTA because of the interference of bismuth oxide. Calcium phosphate and calcite/aragonite bands were detected on all 24-hour-aged cements; portlandite was no longer detected on wTC. ESEM and micro-Raman are powerful and suitable techniques to investigate endodontic calcium silicate hydrated cements in real time and in

  2. Radionucleotide scanning in osteomyelitis

    SciTech Connect

    Sachs, W.; Kanat, I.O.

    1986-07-01

    Radionucleotide bone scanning can be an excellent adjunct to the standard radiograph and clinical findings in the diagnosis of osteomyelitis. Bone scans have the ability to detect osteomyelitis far in advance of the standard radiograph. The sequential use of technetium and gallium has been useful in differentiating cellulitis and osteomyelitis. Serial scanning with technetium and gallium may be used to monitor the response of osteomyelitis to antibiotic therapy.

  3. Abscess scan - radioactive

    MedlinePlus

    ... procedures, or treatments, as they can interfere with test results: Gallium (Ga) scan within the past month Hemodialysis ... Not feeling well (malaise) Pain Often, other imaging tests such as an ultrasound or CT scan may be done first. Normal Results Normal findings would show no abnormal gathering of ...

  4. PET scan for breast cancer

    MedlinePlus

    ... CT scan. This combination scan is called a PET/CT. ... A PET scan is most often used when other tests, such as MRI scan or CT scan, DO NOT provide enough information. A breast PET scan is used only after a woman has ...

  5. Resonant scanning mechanism

    NASA Astrophysics Data System (ADS)

    Wallace, John; Newman, Mike; Gutierrez, Homero; Hoffman, Charlie; Quakenbush, Tim; Waldeck, Dan; Leone, Christopher; Ostaszewski, Miro

    2014-10-01

    Ball Aerospace & Technologies Corp. developed a Resonant Scanning Mechanism (RSM) capable of combining a 250- Hz resonant scan about one axis with a two-hertz triangular scan about the orthogonal axis. The RSM enables a rapid, high-density scan over a significant field of regard (FOR) while minimizing size, weight, and power requirements. The azimuth scan axis is bearing mounted allowing for 30° of mechanical travel, while the resonant elevation axis is flexure and spring mounted with five degrees of mechanical travel. Pointing-knowledge error during quiescent static pointing at room temperature across the full range is better than 100 μrad RMS per axis. The compact design of the RSM, roughly the size of a soda can, makes it an ideal mechanism for use on low-altitude aircraft and unmanned aerial vehicles. Unique aspects of the opto-mechanical design include i) resonant springs which allow for a high-frequency scan axis with low power consumption; and ii) an independent lower-frequency scan axis allowing for a wide FOR. The pointing control system operates each axis independently and employs i) a position loop for the azimuth axis; and ii) a unique combination of parallel frequency and amplitude control loops for the elevation axis. All control and pointing algorithms are hosted on a 200-MHz microcontroller with 516 KB of RAM on a compact 3"×4" digital controller, also of Ball design.

  6. Cardiac CT Scan

    MedlinePlus

    ... rate. Before the test, a contrast dye, often iodine, may be injected into a vein in your ... should not receive more CT scans than the number that clinical guidelines recommend. Another risk is that ...

  7. Nuclear Heart Scan

    MedlinePlus

    ... into your blood and travels to your heart. Nuclear heart scans use single photon emission computed tomography (SPECT) or cardiac positron emission tomography (PET) to detect the energy from the tracer to make pictures of your ...

  8. Cervical MRI scan

    MedlinePlus

    ... magnetic resonance imaging) scan uses energy from strong magnets to create pictures of the part of the ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  9. Leg MRI scan

    MedlinePlus

    ... resonance imaging) scan of the leg uses strong magnets to create pictures of the leg. This may ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  10. Arm MRI scan

    MedlinePlus

    ... arm MRI (magnetic resonance imaging) scan uses strong magnets to create pictures of the upper and lower ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  11. Photothermal imaging scanning microscopy

    DOEpatents

    Chinn, Diane; Stolz, Christopher J.; Wu, Zhouling; Huber, Robert; Weinzapfel, Carolyn

    2006-07-11

    Photothermal Imaging Scanning Microscopy produces a rapid, thermal-based, non-destructive characterization apparatus. Also, a photothermal characterization method of surface and subsurface features includes micron and nanoscale spatial resolution of meter-sized optical materials.

  12. Fiber-Scanned Microdisplays

    NASA Technical Reports Server (NTRS)

    Crossman-Bosworth, Janet; Seibel, Eric

    2010-01-01

    Helmet- and head-mounted display systems, denoted fiber-scanned microdisplays, have been proposed to provide information in an "augmented reality" format (meaning that the information would be optically overlaid on the user's field of view).

  13. Pediatric CT Scans

    Cancer.gov

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  14. Slow Scan Telemedicine

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Originally developed under contract for NASA by Ball Bros. Research Corporation for acquiring visual information from lunar and planetary spacecraft, system uses standard closed circuit camera connected to a device called a scan converter, which slows the stream of images to match an audio circuit, such as a telephone line. Transmitted to its destination, the image is reconverted by another scan converter and displayed on a monitor. In addition to assist scans, technique allows transmission of x-rays, nuclear scans, ultrasonic imagery, thermograms, electrocardiograms or live views of patient. Also allows conferencing and consultation among medical centers, general practitioners, specialists and disease control centers. Commercialized by Colorado Video, Inc., major employment is in business and industry for teleconferencing, cable TV news, transmission of scientific/engineering data, security, information retrieval, insurance claim adjustment, instructional programs, and remote viewing of advertising layouts, real estate, construction sites or products.

  15. 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.

  16. Coronary Calcium Scan

    MedlinePlus

    ... Intramural Research Research Resources Research Meeting Summaries Technology ... complete. A coronary calcium scan uses a special scanner such as an electron beam CT or a multidetector CT (MDCT) machine. ...

  17. Multiple Reflector Scanning Antennas

    NASA Astrophysics Data System (ADS)

    Shen, Bing

    Narrow beamwidth antenna systems are important to remote sensing applications and point-to-point communication systems. In many applications the main beam of the antenna radiation pattern must be scannable over a region of space. Scanning by mechanically skewing the entire antenna assembly is difficult and in many situations is unacceptable. Performance during scan is, of course, also very important. Traditional reflector systems employing the well-focused paraboloidal -shaped main reflector accomplish scan by motion of a few feeds, or by phase steering a focal plane feed array. Such scanning systems can experience significant gain loss. Traditional reflecting systems with a spherical main reflector have low aperture efficiency and poor side lobe and cross polarization performance. This dissertation introduces a new approach to the design of scanning spherical reflector systems, in which the performance weaknesses of high cross polarization and high side lobe levels are avoided. Moreover, the low aperture utilization common in spherical reflectors is overcome. As an improvement to this new spherical main reflector configuration, a flat mirror reflector is introduced to minimize the mechanical difficulties to scan the main beam. In addition to the reflector system design, reflector antenna performance evaluation is also important. The temperature resolution issue important for earth observation radiometer antennas is studied, and a new method to evaluate and optimize such temperature resolution is introduced.

  18. Wide scanning spherical antenna

    NASA Technical Reports Server (NTRS)

    Shen, Bing (Inventor); Stutzman, Warren L. (Inventor)

    1995-01-01

    A novel method for calculating the surface shapes for subreflectors in a suboptic assembly of a tri-reflector spherical antenna system is introduced, modeled from a generalization of Galindo-Israel's method of solving partial differential equations to correct for spherical aberration and provide uniform feed to aperture mapping. In a first embodiment, the suboptic assembly moves as a single unit to achieve scan while the main reflector remains stationary. A feed horn is tilted during scan to maintain the illuminated area on the main spherical reflector fixed throughout the scan thereby eliminating the need to oversize the main spherical reflector. In an alternate embodiment, both the main spherical reflector and the suboptic assembly are fixed. A flat mirror is used to create a virtual image of the suboptic assembly. Scan is achieved by rotating the mirror about the spherical center of the main reflector. The feed horn is tilted during scan to maintain the illuminated area on the main spherical reflector fixed throughout the scan.

  19. Femtosecond scanning tunneling microscope

    SciTech Connect

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

    1998-11-01

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

  20. Vector generator scan converter

    DOEpatents

    Moore, James M.; Leighton, James F.

    1990-01-01

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  1. Vector generator scan converter

    DOEpatents

    Moore, J.M.; Leighton, J.F.

    1988-02-05

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  2. Adaptive Optical Scanning Holography

    PubMed Central

    Tsang, P. W. M.; Poon, Ting-Chung; Liu, J.-P.

    2016-01-01

    Optical Scanning Holography (OSH) is a powerful technique that employs a single-pixel sensor and a row-by-row scanning mechanism to capture the hologram of a wide-view, three-dimensional object. However, the time required to acquire a hologram with OSH is rather lengthy. In this paper, we propose an enhanced framework, which is referred to as Adaptive OSH (AOSH), to shorten the holographic recording process. We have demonstrated that the AOSH method is capable of decreasing the acquisition time by up to an order of magnitude, while preserving the content of the hologram favorably. PMID:26916866

  3. Adaptive Optical Scanning Holography

    NASA Astrophysics Data System (ADS)

    Tsang, P. W. M.; Poon, Ting-Chung; Liu, J.-P.

    2016-02-01

    Optical Scanning Holography (OSH) is a powerful technique that employs a single-pixel sensor and a row-by-row scanning mechanism to capture the hologram of a wide-view, three-dimensional object. However, the time required to acquire a hologram with OSH is rather lengthy. In this paper, we propose an enhanced framework, which is referred to as Adaptive OSH (AOSH), to shorten the holographic recording process. We have demonstrated that the AOSH method is capable of decreasing the acquisition time by up to an order of magnitude, while preserving the content of the hologram favorably.

  4. Beam scanning binary logic

    NASA Astrophysics Data System (ADS)

    Itoh, Hideo; Mukai, Seiji; Watanabe, Masanobu; Mori, Masahiko; Yajima, Hiroyoshi

    1990-07-01

    A beam-scanning laser diode (BSLD) is presently applied to a novel optoelectronic logic operation, designated 'beam-scanning binary logic' (BSBL), that covers the implementation of both the basic logic gates and a spatial code encoder for photodetection, while allowing a greater reduction of the number of active devices than ordinary binary logic operations. BSBL executes multifunctional logic operations simultaneously. The data connections between logic gates in BSLD are flexible, due to the ability to electrically control both output power and laser-beam direction.

  5. Scanning computed confocal imager

    DOEpatents

    George, John S.

    2000-03-14

    There is provided a confocal imager comprising a light source emitting a light, with a light modulator in optical communication with the light source for varying the spatial and temporal pattern of the light. A beam splitter receives the scanned light and direct the scanned light onto a target and pass light reflected from the target to a video capturing device for receiving the reflected light and transferring a digital image of the reflected light to a computer for creating a virtual aperture and outputting the digital image. In a transmissive mode of operation the invention omits the beam splitter means and captures light passed through the target.

  6. Planning for the State Early Childhood Comprehensive Systems Initiative (SECCS): An Environmental Scan of Opportunities and Readiness for Building Systems. Building State Early Childhood Comprehensive Systems Series, No. 2.

    ERIC Educational Resources Information Center

    Halfon, Neal; Uyeda, Kimberly; Inkelas, Moira; Kumar, Vani; Tullis, Ericka; Rice, Thomas

    2004-01-01

    This report outlines the national and state environmental context for the SECCS Initiative in supporting MCH strategic planning in early childhood systems building. This strategic context has implications for roles, relationships, and activities within a planning process and ultimately an implementation process. It summarizes the opportunities and…

  7. Ultrafast scanning probe microscopy

    DOEpatents

    Weiss, Shimon; Chemla, Daniel S.; Ogletree, D. Frank; Botkin, David

    1995-01-01

    An ultrafast scanning probe microscopy method for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample.

  8. CT Scans - Multiple Languages

    MedlinePlus

    ... Tomography) Scan - العربية (Arabic) Bilingual PDF Health Information Translations Chinese, Simplified (Mandarin dialect) (简体中文) Expand Section CT ( ... Chinese, Simplified (Mandarin dialect)) Bilingual PDF Health Information Translations Chinese, Traditional (Cantonese dialect) (繁體中文) Expand Section CT ( ...

  9. The Organizational Scan.

    ERIC Educational Resources Information Center

    Tosti, Donald; Jackson, Stephanie D.

    1997-01-01

    Performance technologists like quick, cheap analysis that is rigorous and comprehensive. This article presents the organization scan model which makes successful compromises between the technologist's obligation to be rigorous and comprehensive and the sponsor's obligation to save money and time. Includes "Societal Bottom Line: Measurable…

  10. ICV Echo Ultrasound Scan

    NASA Image and Video Library

    2012-12-31

    View of Integrated Cardiovascular (ICV) Echo Ultrasound Scan,in the Columbus module. ICV aims to quantify the extent,time course and clinical significance of cardiac atrophy (decrease in the size of the heart muscle) in space. Photo was taken during Expedition 34.

  11. Teaching the SCANS Competencies.

    ERIC Educational Resources Information Center

    Department of Labor, Washington, DC. Secretary's Commission on Achieving Necessary Skills.

    SCANS (the Secretary's Commission on Achieving Necessary Skills) provides definitions of the knowledge students and workers need for workplace success and methods for applying these principles in communities throughout the United States. This document contains six articles that give education and training practitioners practical suggestions for…

  12. SCANS: The Missing Link.

    ERIC Educational Resources Information Center

    Price-Machado, Donna

    Three specific classroom techniques for teaching vocational English as a Second Language to adults are discussed. They are three items on the SCANS (Secretary's Commission on Achieving Necessary Skills) list of "easy things" to do to integrate workplace basics into the classroom, designed to encourage a student-focused classroom. They…

  13. Ultrafast scanning probe microscopy

    DOEpatents

    Weiss, S.; Chemla, D.S.; Ogletree, D.F.; Botkin, D.

    1995-05-16

    An ultrafast scanning probe microscopy method is described for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample. 6 Figs.

  14. Bone scanning in clinical practice

    SciTech Connect

    Fogelman, I. )

    1987-01-01

    The topics covered in this book include the history of bone scanning, mechanisms of uptake of diphosphonate in bone, the normal bone scan, and the role of bone scanning in clinical practice. The aim of this book is to provide a source of reference relating to bone scan imaging for all those who are interested in the skeleton.

  15. Scanning thermal plumes

    NASA Technical Reports Server (NTRS)

    Scarpace, F. L.; Madding, R. P.; Green, T., III

    1975-01-01

    Over a three-year period 800 thermal line scans of power plant plumes were made by an airborne scanner, with ground truth measured concurrently at the plants. Computations using centered finite differences in the thermal scanning imagery show a lower bound in the horizontal temperature gradient in excess of 1.6 C/m. Gradients persist to 3 m below the surface. Vector plots of the velocity of thermal fronts are constructed by tracing the front motion in successive thermal images. A procedure is outlined for the two-point ground calibration of a thermal scanner from an equation describing the scanner signal and the voltage for two known temperatures. The modulation transfer function is then calculated by input of a thermal step function and application of digital time analysis techniques using Fast Fourier Transforms to the voltage output. Field calibration tests are discussed. Data accuracy is limited by the level of ground truth effort chosen.

  16. Scanning thermal plumes

    NASA Technical Reports Server (NTRS)

    Scarpace, F. L.; Madding, R. P.; Green, T., III

    1975-01-01

    Over a three-year period 800 thermal line scans of power plant plumes were made by an airborne scanner, with ground truth measured concurrently at the plants. Computations using centered finite differences in the thermal scanning imagery show a lower bound in the horizontal temperature gradient in excess of 1.6 C/m. Gradients persist to 3 m below the surface. Vector plots of the velocity of thermal fronts are constructed by tracing the front motion in successive thermal images. A procedure is outlined for the two-point ground calibration of a thermal scanner from an equation describing the scanner signal and the voltage for two known temperatures. The modulation transfer function is then calculated by input of a thermal step function and application of digital time analysis techniques using Fast Fourier Transforms to the voltage output. Field calibration tests are discussed. Data accuracy is limited by the level of ground truth effort chosen.

  17. The Scanning Photogrammetry

    NASA Astrophysics Data System (ADS)

    Ke, T.; Zhang, Z. X.; Huang, S.

    2012-07-01

    The paper proposes a new photogrammetry method, the scanning photogrammetry, to solve the problem that large targets can hardly be processed as a whole one in close-range photogrammetry. The method enlarges the view angle and intersection angle effectively by rotating camera in horizontal and vertical direction when photographing large targets. Meanwhile, it is a kind of multi-baseline photogrammetry which increases matching reliability and improves the quality and quantity of observations. Besides, in order to acquire images automatically, we develop the photograph scanner which ensures the efficiency and quality of photography. And the scanning photogrammetry system has been successfully used in deformation monitoring of Wumen Circumvallation in the Forbidden City. In the experiments, data is processed automatically by classical triangulation and self-calibration bundle adjustment. The result proves that the precision can meet with the deformation monitoring requirements and data processing efficiency accomplishes to engineering measurement applications.

  18. Photon scanning tunneling microscopy

    SciTech Connect

    Goudonnet, J.P.; Salomon, L.; De Fornel, F.; Chabrier, G. . Lab. de Physique du Solide); Warmack, R.J.; Ferrell, T.L. )

    1990-01-01

    The Photon Scanning Tunneling Microscopy (PSTM) is the photon analogue of the electron Scanning Tunneling Microscope (STM). It uses the evanescent field due to the total internal reflection of a light beam in a Total Internal Reflection (TIR) prism. The sample, mounted on the base of the prism, modulates the evanescent field. A sharpened optical fiber probes this field, and the collected light is processed to generate an image of the topography and the chemical composition of the surface. We give, in this paper, a description of the microscope and discuss the influence of several parameters such as -- polarization of light, angle of incidence, shape of the end of the fiber -- on the resolution. Images of various samples -- glass samples, teflon spheres -- are presented. 8 refs., 7 figs.

  19. Scanning holographic optical tweezers.

    PubMed

    Shaw, L A; Panas, Robert M; Spadaccini, C M; Hopkins, J B

    2017-08-01

    The aim of this Letter is to introduce a new optical tweezers approach, called scanning holographic optical tweezers (SHOT), which drastically increases the working area (WA) of the holographic-optical tweezers (HOT) approach, while maintaining tightly focused laser traps. A 12-fold increase in the WA is demonstrated. The SHOT approach achieves its utility by combining the large WA of the scanning optical tweezers (SOT) approach with the flexibility of the HOT approach for simultaneously moving differently structured optical traps in and out of the focal plane. This Letter also demonstrates a new heuristic control algorithm for combining the functionality of the SOT and HOT approaches to efficiently allocate the available laser power among a large number of traps. The proposed approach shows promise for substantially increasing the number of particles that can be handled simultaneously, which would enable optical tweezers additive fabrication technologies to rapidly assemble microgranular materials and structures in reasonable build times.

  20. Scanning micro-sclerometer

    DOEpatents

    Oliver, Warren C.; Blau, Peter J.

    1994-01-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch.

  1. Fly-scan ptychography

    DOE PAGES

    Huang, Xiaojing; Lauer, Kenneth; Clark, Jesse N.; ...

    2015-03-13

    We report an experimental ptychography measurement performed in fly-scan mode. With a visible-light laser source, we demonstrate a 5-fold reduction of data acquisition time. By including multiple mutually incoherent modes into the incident illumination, high quality images were successfully reconstructed from blurry diffraction patterns. Thus, this approach significantly increases the throughput of ptychography, especially for three-dimensional applications and the visualization of dynamic systems.

  2. Optical scanning holographic microscopy

    NASA Astrophysics Data System (ADS)

    Poon, Ting-Chung; Doh, Kyu B.; Schilling, Bradley W.; Wu, Ming H.; Shinoda, Kazunori K.; Suzuki, Yoshiji

    1995-03-01

    We first review a newly developed 3D imaging technique called optical scanning holography (OSH), and discuss recording and reconstruction of a point object using the principle of OSH. We then derive 3D holographic magnification, using three points configured as a 3D object. Finally, we demonstrated 3D imaging capability of OSH by holographically recording two planar objects at different depths and reconstructing the hologram digitally.

  3. Scanning drop sensor

    DOEpatents

    Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Shinde, Aniketa A.; Guevarra, Dan W.; Jones, Ryan J.; Marcin, Martin R.; Mitrovic, Slobodan

    2017-05-09

    Electrochemical or electrochemical and photochemical experiments are performed on a collection of samples by suspending a drop of electrolyte solution between an electrochemical experiment probe and one of the samples that serves as a test sample. During the electrochemical experiment, the electrolyte solution is added to the drop and an output solution is removed from the drop. The probe and collection of samples can be moved relative to one another so the probe can be scanned across the samples.

  4. Scanning drop sensor

    DOEpatents

    Jin, Jian; Xiang, Chengxiang; Gregoire, John

    2017-05-09

    Electrochemical experiments are performed on a collection of samples by suspending a drop of electrolyte solution between an electrochemical experiment probe and one of the samples that serves as a test sample. During the electrochemical experiment, the electrolyte solution is added to the drop and an output solution is removed from the drop. The probe and collection of samples can be moved relative to one another so the probe can be scanned across the samples.

  5. Fly-scan ptychography

    SciTech Connect

    Huang, Xiaojing; Lauer, Kenneth; Clark, Jesse N.; Xu, Weihe; Nazaretski, Evgeny; Harder, Ross; Robinson, Ian K.; Chu, Yong S.

    2015-03-13

    We report an experimental ptychography measurement performed in fly-scan mode. With a visible-light laser source, we demonstrate a 5-fold reduction of data acquisition time. By including multiple mutually incoherent modes into the incident illumination, high quality images were successfully reconstructed from blurry diffraction patterns. This approach significantly increases the throughput of ptychography, especially for three-dimensional applications and the visualization of dynamic systems.

  6. Scanning micro-sclerometer

    DOEpatents

    Oliver, W.C.; Blau, P.J.

    1994-11-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch. 2 figs.

  7. Underwater laser scanning system

    NASA Astrophysics Data System (ADS)

    Austin, Roswell W.; Duntley, Seibert Q.; Ensminger, Richard L.; Petzold, Theodore J.; Smith, Raymond C.

    1991-12-01

    A system is described that produces high quality images through turbid waters by means of time encoded reflected light transmitted by scattering. The system consists of a compact battery operated laser scanning unit that scans the underwater scene with the laser beam in a manner similar to a television raster. Light reflected from any object in the scene varies in accordance with the reflectance of the minute spot being illuminated. This time varying intensity (TVI) signal is transmitted through the water to a remote receiver by both scattered and unscattered light where the received signal may be stored and/or displayed. The underwater laser scanning unit can be moved freely about the field of interest by scuba diver or ROV, unencumbered by entangling umbilicals, and can send real-time images over distances of 15 to 20 attenuation lengths to observers in a shirt-sleeve environment for critical viewing on an image display monitor. This previously undescribed system was developed in the early 1970s for proof of concept tests and used technology that is now 18 or more years old. The physical principles and the experimental hardware are described and examples are given of images providing exquisite detail that were made in an experimental tank together with some images obtained in ocean trials.

  8. Forensic Scanning Electron Microscope

    NASA Astrophysics Data System (ADS)

    Keeley, R. H.

    1983-03-01

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

  9. CONFOCAL LASER SCANNING MICROSCOPY OF APOPTOSIS IN WHOLE MOUSE AND RAT OVARIES

    EPA Science Inventory

    Confocal Laser Scanning Microscopy of Apoptosis in Whole Mouse and Rat Ovaries. Robert M. Zucker Susan C. Jeffay and Sally D. Perreault Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research ...

  10. CONFOCAL LASER SCANNING MICROSCOPY OF APOPTOSIS IN WHOLE MOUSE AND RAT OVARIES

    EPA Science Inventory

    Confocal Laser Scanning Microscopy of Apoptosis in Whole Mouse and Rat Ovaries. Robert M. Zucker Susan C. Jeffay and Sally D. Perreault Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research ...

  11. Scanning radiographic apparatus

    SciTech Connect

    Albert, R.D.

    1980-04-01

    Visual display of dental, medical or other radiographic images is realized with an x-ray tube in which an electron beam is scanned through an x-y raster pattern on a broad anode plate, the scanning being synchronized with the x-y sweep signals of a cathode ray tube display and the intensity signal for the display being derived from a small x-ray detector which receives x-rays that have passed through the subject to be imaged. Positioning and support of the detector are provided for by disposing the detector in a probe which may be attached to the x-ray tube at any of a plurality of different locations and by providing a plurality of such probes of different configuration in order to change focal length, to accommodate to different detector placements relative to the subject, to enhance patient comfort and to enable production of both periapical images and wider angle pantomographic images. High image definition with reduced radiation dosage is provided for by a lead glass collimator situated between the x-ray tube and subject and having a large number of spaced-apart minute radiation transmissive passages convergent on the position of the detector. Releasable mounting means enable changes of collimator in conjunction with changes of the probe to change focal length. A control circuit modifies the x-y sweep signals applied to the x-ray tube and modulates electron beam energy and current in order to correct for image distortions and other undesirable effects which can otherwise be present in a scanning x-ray system.

  12. Battery scanning system

    SciTech Connect

    Dieu, L.F.

    1984-11-20

    A battery scanning system which is capable of monitoring and displaying the voltage of each cell in a battery or upon command provides the cell voltage distribution by displaying the cell number and voltage value of highest and lowest cell. The system has a digital logic system, display, input switches for operator generated variables, an alarm, relays, relay selection gates, an optically coupled isolation amplifier, power source and an analog-digital converter. The optically coupled analog amplifier electrically isolates the system from the battery so that large voltage offsets will not adversely affect the automatic measuring of the cells.

  13. Real Scan Evolution.

    DTIC Science & Technology

    1982-02-01

    Computer Image Generation Visual Simulation Computer Graphics Al gortthm Geometric Model tng 1%ABSTRACT (C.tla. -mm. .00n ad N ue-e""V ONd Ofmi* OF 61"knsee...envtronments. modeled as a single valued el evatYo fnction of horizontal location. The objecttve of the development was to analyze the feasibility of a real...generator capable of creating complex Imagery .in real time? Is the solution amenable to efficient off-lne modeling of complex environments? The Real Scan

  14. Scanning Quantum Dot Microscopy

    NASA Astrophysics Data System (ADS)

    Wagner, Christian; Green, Matthew F. B.; Leinen, Philipp; Deilmann, Thorsten; Krüger, Peter; Rohlfing, Michael; Temirov, Ruslan; Tautz, F. Stefan

    2015-07-01

    We introduce a scanning probe technique that enables three-dimensional imaging of local electrostatic potential fields with subnanometer resolution. Registering single electron charging events of a molecular quantum dot attached to the tip of an atomic force microscope operated at 5 K, equipped with a qPlus tuning fork, we image the quadrupole field of a single molecule. To demonstrate quantitative measurements, we investigate the dipole field of a single metal adatom adsorbed on a metal surface. We show that because of its high sensitivity the technique can probe electrostatic potentials at large distances from their sources, which should allow for the imaging of samples with increased surface roughness.

  15. Controlled Scanning Probe Lithography

    NASA Astrophysics Data System (ADS)

    Ruskell, Todd G.; Sarid, Dror; Workman, Richard K.; Pyle, Jason L.

    1997-03-01

    A method for real-time monitoring of the quality and quantity of silicon oxide grown on silicon using conducting-tip scanning probe lithography has been developed. The sub-picoampere tip-sample currents measured during lithography in ambient conditions are shown to be proportional to the amount of silicon oxide being grown. In addition, we have demonstrated the ability to control the composition of the grown material by altering the lithographic environment. Silicon nitride growth is shown to result from lithography on silicon samples in an environment of annhydrous ammonia.

  16. Free motion scanning system

    DOEpatents

    Sword, Charles K.

    2000-01-01

    The present invention relates to an ultrasonic scanner system and method for the imaging of a part system, the scanner comprising: a probe assembly spaced apart from the surface of the part including at least two tracking signals for emitting radiation and a transmitter for emitting ultrasonic waves onto a surface in order to induce at least a portion of the waves to be reflected from the part, at least one detector for receiving the radiation wherein the detector is positioned to receive the radiation from the tracking signals, an analyzer for recognizing a three-dimensional location of the tracking signals based on the emitted radiation, a differential converter for generating an output signal representative of the waveform of the reflected waves, and a device such as a computer for relating said tracking signal location with the output signal and projecting an image of the resulting data. The scanner and method are particularly useful to acquire ultrasonic inspection data by scanning the probe over a complex part surface in an arbitrary scanning pattern.

  17. Ultrafast scanning tunneling microscopy

    SciTech Connect

    Botkin, D.A. |

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  18. Photon scanning tunneling microscopy

    SciTech Connect

    Reddick, R.C.; Warmack, R.J.; Chilcott, D.W.; Sharp, S.L.; Ferrell, T.L. Department of Physics and Astronomy, University of Tennessee, Knoxville, TN )

    1990-12-01

    An optical tunneling microscope is presented that operates in exactly the same way as the electron scanning tunneling microscope (ESTM). It takes advantage of evanescent fields generated by the total internal reflection (TIR) of light at the interface between materials of different optical densities. The photon scanning tunneling microscope (PSTM) employs an optically conducting probe tip to map spatial variations in the evanescent and scattered field intensity distributions adjacent to a sample surface, which forms or is placed on the TIR surface. These variations are due to the local topography, morphology, and optical activity of the surface and form the basis of imaging. Evanescent field theory is discussed and the evanescent field intensity as a function of surface-probe separation is calculated using several probe tip models. After a description of PSTM construction and operation, evanescent field intensity measurements are shown to agree with the model calculations. PSTM images of various sample surfaces demonstrate subwavelength resolution exceeding that of conventional optical microscopy, especially in the vertical dimension. Limitations and interpretation of PSTM images are discussed as well as the PSTMs applicability to other forms of surface analysis.

  19. Pulmonary ventilation/perfusion scan

    MedlinePlus

    ... JavaScript. A pulmonary ventilation/perfusion scan involves two nuclear scan tests to measure breathing (ventilation) and circulation ( ... In: Mettler FA, Guiberteau MJ, eds. Essentials of Nuclear Medicine Imaging . 6th ed. Philadelphia, PA: Elsevier Saunders; ...

  20. Rotational scanning atomic force microscopy.

    PubMed

    Ulčinas, A; Vaitekonis, Š

    2017-03-10

    A non-raster scanning technique for atomic force microscopy (AFM) imaging which combines rotational and translational motion is presented. The use of rotational motion for the fast scan axis allows us to significantly increase the scanning speed while imaging a large area (diameter > 30 μm). An image reconstruction algorithm and the factors influencing the resolution of the technique are discussed. The experimental results show the potential of the rotational scanning technique for high-throughput large area AFM investigation.

  1. Rotational scanning atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Ulčinas, A.; Vaitekonis, Š.

    2017-03-01

    A non-raster scanning technique for atomic force microscopy (AFM) imaging which combines rotational and translational motion is presented. The use of rotational motion for the fast scan axis allows us to significantly increase the scanning speed while imaging a large area (diameter > 30 μm). An image reconstruction algorithm and the factors influencing the resolution of the technique are discussed. The experimental results show the potential of the rotational scanning technique for high-throughput large area AFM investigation.

  2. Telescopic horizon scanning.

    PubMed

    Koenderink, Jan

    2014-12-20

    The problem of "distortionless" viewing with terrestrial telescopic systems (mainly "binoculars") remains problematic. The so called "globe effect" is only partially counteracted in modern designs. Theories addressing the phenomenon have never reached definitive closure. In this paper, we show that exact distortionless viewing with terrestrial telescopic systems is not possible in general, but that it is in principle possible in-very frequent in battle field and marine applications-the case of horizon scanning. However, this involves cylindrical optical elements. For opto-electronic systems, a full solution is more readily feasible. The solution involves a novel interpretation of the relevant constraints and objectives. For final design decisions, it is not necessary to rely on a corpus of psychophysical (or ergonomic) data, although one has to decide whether the instrument is intended as an extension of the eye or as a "pictorial" device.

  3. Fetal cardiac scanning today.

    PubMed

    Allan, Lindsey

    2010-07-01

    The ability to examine the structure of the fetal heart in real-time started over 30 years ago now. The field has seen very great advances since then, both in terms of technical improvements in ultrasound equipment and in dissemination of operator skills. A great deal has been learnt about normal cardiac function in the human fetus throughout gestation and how it is affected by pathologies of pregnancy. There is increasing recognition of abnormal heart structure during routine obstetric scanning, allowing referral for specialist diagnosis and counselling. It is now possible to make accurate diagnosis of cardiac malformations as early as 12 weeks of gestation. Early diagnosis of a major cardiac malformation in the fetus can provide the parents with a comprehensive prognosis, enabling them to make the most informed choice about the management of the pregnancy.

  4. A scanning cavity microscope

    PubMed Central

    Mader, Matthias; Reichel, Jakob; Hänsch, Theodor W.; Hunger, David

    2015-01-01

    Imaging the optical properties of individual nanosystems beyond fluorescence can provide a wealth of information. However, the minute signals for absorption and dispersion are challenging to observe, and only specialized techniques requiring sophisticated noise rejection are available. Here we use signal enhancement in a high-finesse scanning optical microcavity to demonstrate ultra-sensitive imaging. Harnessing multiple interactions of probe light with a sample within an optical resonator, we achieve a 1,700-fold signal enhancement compared with diffraction-limited microscopy. We demonstrate quantitative imaging of the extinction cross-section of gold nanoparticles with a sensitivity less than 1 nm2; we show a method to improve the spatial resolution potentially below the diffraction limit by using higher order cavity modes, and we present measurements of the birefringence and extinction contrast of gold nanorods. The demonstrated simultaneous enhancement of absorptive and dispersive signals promises intriguing potential for optical studies of nanomaterials, molecules and biological nanosystems. PMID:26105690

  5. Earth observing scanning polarimeter

    NASA Technical Reports Server (NTRS)

    Travis, Larry

    1993-01-01

    Climate forcing by tropospheric aerosols is receiving increased attention because of the realization that the climate effects may be large, while our knowledge of global aerosol characteristics and temporal changes is very poor. Tropospheric aerosols cause a direct radiative forcing due simply to their scattering and absorption of solar radiation, as well as an indirect effect as cloud condensation nuclei which can modify the shortwave reflectivity of clouds. Sulfate aerosols tend to increase planetary albedo through both the direct and indirect effects; a cooling due to anthropogenic sulfate aerosols has been estimated of order 1 W/sq m, noting that this is similar in magnitude to the present anthropogenic greenhouse gas warming. Other aerosols, including those from biomass burning and wind-blown desert dust are also of potential climatic importance. At present, the only global monitoring of tropospheric aerosols is a NOAA operational product, aerosol optical thickness, obtained using channel-1 (0.58-0.68 mu m) radiances from the AVHRR. With this single channel radiance data, one must use an approach which is based on the inferred excess of reflected radiance owing to scattering by the aerosols over that expected from theoretical calculations. This approach is suited only for situations where the surface has a low albedo that is well known a priori. Thus, the NOAA operational product is restricted to coverage over the ocean at AVHRR scan angles well away from sun glint, and aerosol changes are subject to confusion with changes caused by either optically thin or subpixel clouds. Because optically thin aerosols have only a small effect on the radiance, accurate measurements for optical thickness less than 0.1 (which is a typical background level) are precluded. Moreover, some of the largest and most important aerosol changes are expected over land. The Earth Observing Scanning Polarimeter (EOSP) instrument, based upon design heritage and analysis techniques

  6. Differential scanning calorimetry.

    PubMed

    Spink, Charles H

    2008-01-01

    Differential scanning calorimetry (DSC) has emerged as a powerful experimental technique for determining thermodynamic properties of biomacromolecules. The ability to monitor unfolding or phase transitions in proteins, polynucleotides, and lipid assemblies has not only provided data on thermodynamic stability for these important molecules, but also made it possible to examine the details of unfolding processes and to analyze the characteristics of intermediate states involved in the melting of biopolymers. The recent improvements in DSC instrumentation and software have generated new opportunities for the study of the effects of structure and changes in environment on the behavior of proteins, nucleic acids, and lipids. This review presents some of the details of application of DSC to the examination of the unfolding of biomolecules. After a brief introduction to DSC instrumentation used for the study of thermal transitions, the methods for obtaining basic thermodynamic information from the DSC curve are presented. Then, using DNA unfolding as an example, methods for the analysis of the melting transition are presented that allow deconvolution of the DSC curves to determine more subtle characteristics of the intermediate states involved in unfolding. Two types of transitions are presented for analysis, the first example being the unfolding of two large synthetic polynucleotides, which display high cooperativity in the melting process. The second example shows the application of DSC for the study of the unfolding of a simple hairpin oligonucleotide. Details of the data analysis are presented in a simple spreadsheet format.

  7. GPR scan assessment

    NASA Astrophysics Data System (ADS)

    Abbas, Abbas M.; Salah, Hany; Massoud, Usama; Fouad, Mona; Abdel-Hafez, Mahmoud

    2015-06-01

    Mekaad Radwan monument is situated in the neighborhood of Bab Zuweila in the historical Cairo, Egypt. It was constructed at the middle XVII century (1635 AD). The building has a rectangle shape plan (13 × 6 m) with the longitudinal sides approximately WNW-ESE. It comprises three storages namely; the ground floor; the opened floor (RADWAN Bench) and the living floor with a total elevation of 15 m above the street level. The building suffers from severe deterioration phenomena with patterns of damage which have occurred over time. These deterioration and damages could be attributed to foundation problems, subsoil water and also to the earthquake that affected the entire Greater Cairo area in October 1992. Ground Penetrating Radar (GPR) scan was accomplished against the walls of the opened floor (RADWAN Bench) to evaluate the hazard impact on the walls textures and integrity. The results showed an anomalous feature through the southern wall of RADWAN Bench. A mathematical model has been simulated to confirm the obtained anomaly and the model response exhibited a good matching with the outlined anomaly.

  8. LANL Robotic Vessel Scanning

    SciTech Connect

    Webber, Nels W.

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  9. Electrically scanning microwave radiometer for Nimbus E

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An electronically scanning microwave radiometer system has been designed, developed, and tested for measurement of meteorological, geomorphological and oceanographic parameters from NASA/GSFC's Nimbus E satellite. The system is a completely integrated radiometer designed to measure the microwave brightness temperature of the earth and its atmosphere at a microwave frequency of 19.35 GHz. Calibration and environmental testing of the system have successfully demonstrated its ability to perform accurate measurements in a satellite environment. The successful launch and data acquisition of the Nimbus 5 (formerly Nimbus E) gives further demonstration to its achievement.

  10. Continuous scanning mode for ptychography

    SciTech Connect

    Clark, Jesse N.; Huang, Xiaojing; Harder, Ross; Robinson, Ian K.

    2014-10-15

    We outline how ptychographic imaging can be performed without the need for discrete scan positions. Through an idealized experiment, we demonstrate how a discrete-position scan regime can be replaced with a continuously scanned one with suitable modification of the reconstruction scheme based on coherent modes. The impact of this is that acquisition times can be reduced, significantly aiding ptychographic imaging with x rays, electrons, or visible light.

  11. Continuous scanning mode for ptychography

    SciTech Connect

    Clark, Jesse N.; Huang, Xiaojing; Harder, Ross J.; Robinson, Ian K.

    2014-10-15

    We outline how ptychographic imaging can be performed without the need for discrete scan positions. Through an idealized experiment, we demonstrate how a discrete-position scan regime can be replaced with a continuously scanned one with suitable modification of the reconstruction scheme based on coherent modes. Thus, the impact of this is that acquisition times can be reduced, significantly aiding ptychographic imaging with x rays, electrons, or visible light.

  12. Continuous scanning mode for ptychography

    SciTech Connect

    Clark, Jesse N.; Huang, Xiaojing; Harder, Ross J.; Robinson, Ian K.

    2014-01-01

    Here, we outline how ptychographic imaging can be performed without the need for discrete scan positions. Through an idealized experiment, we demonstrate how a discrete-position scan regime can be replaced with a continuously scanned one with suitable modification of the reconstruction scheme based on coherent modes. Furthermore, the impact of this is that acquisition times can be reduced, significantly aiding ptychographic imaging with x rays, electrons, or visible light.

  13. Lung Ventilation/Perfusion Scan

    MedlinePlus

    ... Scan Lung VQ Scan Related Topics Arrhythmia Cough Deep Vein Thrombosis Pulmonary Embolism Send a link to NHLBI to someone by ... this topic. Related reading Chest X Ray Cough Deep Vein Thrombosis Pulmonary Embolism Rate This Content: Updated: December 9, 2016 Twitter ...

  14. An interchangeable scanning Hall probe/scanning SQUID microscope

    SciTech Connect

    Tang, Chiu-Chun; Lin, Hui-Ting; Wu, Sing-Lin; Chen, Tse-Jun; Wang, M. J.; Ling, D. C.; Chi, C. C.; Chen, Jeng-Chung

    2014-08-15

    We have constructed a scanning probe microscope for magnetic imaging, which can function as a scanning Hall probe microscope (SHPM) and as a scanning SQUID microscope (SSM). The scanning scheme, applicable to SHPM and SSM, consists of a mechanical positioning (sub) micron-XY stage and a flexible direct contact to the sample without a feedback control system for the Z-axis. With the interchangeable capability of operating two distinct scanning modes, our microscope can incorporate the advantageous functionalities of the SHPM and SSM with large scan range up to millimeter, high spatial resolution (⩽4 μm), and high field sensitivity in a wide range of temperature (4.2 K-300 K) and magnetic field (10{sup −7} T-1 T). To demonstrate the capabilities of the system, we present magnetic images scanned with SHPM and SSM, including a RbFeB magnet and a nickel grid pattern at room temperature, surface magnetic domain structures of a La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin film at 77 K, and superconducting vortices in a striped niobium film at 4.2 K.

  15. The value of brain scanning

    PubMed Central

    Riddoch, D.; Drolc, Z.

    1972-01-01

    Over a 3-year period, 667 brain scans were performed, of which the results in 632 have been analysed. Positive scans were found in 68% of 204 cerebral tumours. There was a high rate of detection of meningiomas and malignant gliomas. Scanning was less helpful in visualizing slowly growing gliomas, and those tumours situated in the mid-line or posterior fossa. Metastases occupied an intermediate position. Positive scans occurred in a proportion of patients following acute cerebro-vascular accidents, and in a few other miscellaneous disorders. Virtually all patients with transient cerebral ischaemia, migraine, epilepsy and presenile dementia had normal brain scans. The value and limitations of this investigation have been discussed. PMID:5076491

  16. Multitip scanning bio-Kelvin probe

    NASA Astrophysics Data System (ADS)

    Baikie, I. D.; Smith, P. J. S.; Porterfield, D. M.; Estrup, P. J.

    1999-03-01

    We have developed a novel multitip scanning Kelvin probe which can measure changes in biological surface potential ΔVs to within 2 mV and, quasisimultaneously monitor displacement to <1 μm. The control and measurement subcomponents are PC based and incorporate a flexible user interface permitting software control of each individual tip, measurement, and scan parameters. We review the mode of operation and design features of the scanning bio-Kelvin probe including tip steering, signal processing, tip calibration, and novel tip tracking/dithering routines. This system uniquely offers both tip-to-sample spacing control (which is essential to avoid spurious changes in ΔVs due to variations in mean spacing) and a dithering routine to maintain tip orientation to the biological specimen, irrespective of the latter's movement. These features permit long term (>48 h) "active" tracking of the displacement and biopotentials developed along and around a plant shoot in response to an environmental stimulus, e.g., differential illumination (phototropism) or changes in orientation (gravitropism).

  17. Rapid-scan EPR imaging

    NASA Astrophysics Data System (ADS)

    Eaton, Sandra S.; Shi, Yilin; Woodcock, Lukas; Buchanan, Laura A.; McPeak, Joseph; Quine, Richard W.; Rinard, George A.; Epel, Boris; Halpern, Howard J.; Eaton, Gareth R.

    2017-07-01

    In rapid-scan EPR the magnetic field or frequency is repeatedly scanned through the spectrum at rates that are much faster than in conventional continuous wave EPR. The signal is directly-detected with a mixer at the source frequency. Rapid-scan EPR is particularly advantageous when the scan rate through resonance is fast relative to electron spin relaxation rates. In such scans, there may be oscillations on the trailing edge of the spectrum. These oscillations can be removed by mathematical deconvolution to recover the slow-scan absorption spectrum. In cases of inhomogeneous broadening, the oscillations may interfere destructively to the extent that they are not visible. The deconvolution can be used even when it is not required, so spectra can be obtained in which some portions of the spectrum are in the rapid-scan regime and some are not. The technology developed for rapid-scan EPR can be applied generally so long as spectra are obtained in the linear response region. The detection of the full spectrum in each scan, the ability to use higher microwave power without saturation, and the noise filtering inherent in coherent averaging results in substantial improvement in signal-to-noise relative to conventional continuous wave spectroscopy, which is particularly advantageous for low-frequency EPR imaging. This overview describes the principles of rapid-scan EPR and the hardware used to generate the spectra. Examples are provided of its application to imaging of nitroxide radicals, diradicals, and spin-trapped radicals at a Larmor frequency of ca. 250 MHz.

  18. Advantages of Environmental Scanning Electron Microscopy in Studies of Microorganisms

    DTIC Science & Technology

    1993-01-01

    disruption of sporangia. Uncoated algal cells of Euglena gracilis and Spirogyra sp. were examined using the backscatter electron detector (BSE) and the...agar. (Fig. 7). Uncoated, freeze-dried Euglena sp. cells exam- ined with either ESD or BSE detectors did not exhibit Specimen Preparation for ESEM...P.L. (1967) Observations in the fine struc- Biofilms: An ESEM evaluation of artifacts introduced during SEM ture of the pellicle pores of Euglena

  19. An Exploration of Open Innovation: An Environmental Scanning Perspective

    ERIC Educational Resources Information Center

    Elci, Nuray

    2009-01-01

    Globalization and direction toward a knowledge economy, along with an economic downturn, is creating a competitive environment that calls for corporations to become more innovative. As the business environment becomes more competitive and dynamic, corporations are looking for new ways of achieving innovation. Open innovation is one approach that…

  20. Using External Environmental Scanning and Forecasting to Improve Strategic Planning

    ERIC Educational Resources Information Center

    Lapin, Joel D.

    2004-01-01

    The effectiveness of community colleges is increasingly dependent on their understanding of the external environment and their capacity to forecast and respond to the changing external landscape. As a result, they need to establish a system to continuously monitor changes in that environment and to identify and weigh the implications of changes on…

  1. An Exploration of Open Innovation: An Environmental Scanning Perspective

    ERIC Educational Resources Information Center

    Elci, Nuray

    2009-01-01

    Globalization and direction toward a knowledge economy, along with an economic downturn, is creating a competitive environment that calls for corporations to become more innovative. As the business environment becomes more competitive and dynamic, corporations are looking for new ways of achieving innovation. Open innovation is one approach that…

  2. Using External Environmental Scanning and Forecasting to Improve Strategic Planning

    ERIC Educational Resources Information Center

    Lapin, Joel D.

    2004-01-01

    The effectiveness of community colleges is increasingly dependent on their understanding of the external environment and their capacity to forecast and respond to the changing external landscape. As a result, they need to establish a system to continuously monitor changes in that environment and to identify and weigh the implications of changes on…

  3. Environmental Scan, 2002-03: Governance and Accountability.

    ERIC Educational Resources Information Center

    Association of Colleges of Applied Arts and Technology of Ontario, North York.

    Ontario's Colleges of Applied Arts and Technology have been governed by the Ministry of Training, Colleges, and Universities Act (MTCU) and related regulations and policies since their inception in 1965. In June 2002, the Ontario Colleges of Applied Arts and Technology Act, 2002 (OCAATA) was passed by the Ontario legislature; proclamation is…

  4. ONS 2002 environmental scan: a basis for strategic planning.

    PubMed

    Mafrica, Leonard; Ballon, Layla G; Culhane, Bridget; McCorkle, Michele; Miller Murphy, Cynthia; Worrall, Linda

    2002-10-01

    To analyze information about the environments in which the Oncology Nursing Society (ONS) operates as a basis for strategic planning. Published reports and ONS internal surveys. Analysis of internal and external trends resulted in a list of implications with regard to managing change, avoiding mistakes, and identifying critical issues for ONS leadership. The team presented ONS leaders with a tool that helped to guide the development of the 2003-2006 Strategic Plan. The continuing vitality of professional nursing societies such as ONS is critical to the vitality of the profession of nursing itself. Monitoring the environment in which these organizations operate--and effectively using the knowledge that is gained--contributes to their long-term viability and growth. A stronger ONS is in a position to better serve its members, who ensure high-quality care to people with cancer.

  5. Environmental Scan of the Greater Sacramento Area, 1999.

    ERIC Educational Resources Information Center

    Los Rios Community Coll. District, Sacramento, CA. Office of Planning and Research.

    This report provides a comprehensive look at the external environment impacting Los Rios Community College District (LRCCD) (California). It summarizes the social, economic, and political changes at the state and national levels, in general, and in the Sacramento-Yolo Consolidated Metropolitan Statistical Area (CMSA) served by LRCCD, more…

  6. An Environmental Scan of Northern Alameda County. Revised.

    ERIC Educational Resources Information Center

    Peralta Community Coll. District, Oakland, CA. Office of Research, Planning and Development.

    An overview is provided of the demographic and economic characteristics of the geographical area defined by the Peralta Community College District's boundaries in Northern Alameda County, California. In addition, projections are presented concerning the population and economy of the county until the year 2005. Highlighted findings of the…

  7. Re-scan confocal microscopy: scanning twice for better resolution

    PubMed Central

    De Luca, Giulia M.R.; Breedijk, Ronald M.P.; Brandt, Rick A.J.; Zeelenberg, Christiaan H.C.; de Jong, Babette E.; Timmermans, Wendy; Azar, Leila Nahidi; Hoebe, Ron A.; Stallinga, Sjoerd; Manders, Erik M.M.

    2013-01-01

    We present a new super-resolution technique, Re-scan Confocal Microscopy (RCM), based on standard confocal microscopy extended with an optical (re-scanning) unit that projects the image directly on a CCD-camera. This new microscope has improved lateral resolution and strongly improved sensitivity while maintaining the sectioning capability of a standard confocal microscope. This simple technology is typically useful for biological applications where the combination high-resolution and high-sensitivity is required. PMID:24298422

  8. Circular Scan Streak Tube Development

    NASA Technical Reports Server (NTRS)

    Nevin, S.

    1980-01-01

    A streak tube having circular scan was designed, built and tested. Continuous circular scan, easily derived from out of phase sine waves applied to the conventional deflection plates, permits the timing of pulses traveling long baselines. At the tube's output a circular array of 720 elements is scanned to provide 30 to 40 picosecond resolution. Initial difficulties with electron bombarded silicon arrays were circumvented by using microchannel plates within the streak tube to provide the needed electronic amplification and digital sensitivity and coupling the 720 element arrays to the electron beam by means of a phosphor on a fiber optics. Two ceramic body tubes with S-20 photocathodes were tested and delivered.

  9. Radioisotope scanning of the lungs

    PubMed Central

    Bell, T. K.; Ferguson, R.; McIlrath, E. I.; Weaver, J. A.

    1968-01-01

    Lung scanning with macroaggregated albumin 131I was carried out in 128 patients. The technique appears to be without hazard. It is particularly useful in the detection of pulmonary embolism, but the pattern is non-specific and changes occur in other cardio-respiratory diseases. On the basis of these observations pulmonary scanning is regarded as a useful adjunct in the study of pulmonary embolism, but it cannot serve as a specific diagnostic procedure since similar patterns of scan may be found in many conditions. Images PMID:4230042

  10. 3D Scan Systems Integration

    DTIC Science & Technology

    2007-11-02

    AGENCY USE ONLY (Leave Blank) 2. REPORT DATE 5 Feb 98 4. TITLE AND SUBTITLE 3D Scan Systems Integration REPORT TYPE AND DATES COVERED...2-89) Prescribed by ANSI Std. Z39-1 298-102 [ EDO QUALITY W3PECTEDI DLA-ARN Final Report for US Defense Logistics Agency on DDFG-T2/P3: 3D...SCAN SYSTEMS INTEGRATION Contract Number SPO100-95-D-1014 Contractor Ohio University Delivery Order # 0001 Delivery Order Title 3D Scan Systems

  11. Bone Densitometry (Bone Density Scan)

    MedlinePlus

    ... In some communities, a CT scan with special software can also be used to diagnose or monitor ... patient's bone mineral density. DEXA machines feature special software that compute and display the bone density measurements ...

  12. Studies in Scanning Probe Microscopy.

    DTIC Science & Technology

    2007-11-02

    refereed journals, as well as two books titled Scanning Force Microscopy, With Applications to Electric, Magnetic, and Atomic Forces published by Oxford University Press in 1991 and a revised edition in 1994.

  13. Retinal locus for scanning text.

    PubMed

    Timberlake, George T; Sharma, Manoj K; Grose, Susan A; Maino, Joseph H

    2006-01-01

    A method of mapping the retinal location of text during reading is described in which text position is plotted cumulatively on scanning laser ophthalmoscope retinal images. Retinal locations that contain text most often are the brightest in the cumulative plot, and locations that contain text least often are the darkest. In this way, the retinal area that most often contains text is determined. Text maps were plotted for eight control subjects without vision loss and eight subjects with central scotomas from macular degeneration. Control subjects' text maps showed that the fovea contained text most often. Text maps of five of the subjects with scotomas showed that they used the same peripheral retinal area to scan text and fixate. Text maps of the other three subjects with scotomas showed that they used separate areas to scan text and fixate. Retinal text maps may help evaluate rehabilitative strategies for training individuals with central scotomas to use a particular retinal area to scan text.

  14. Liver echinococcus - CT scan (image)

    MedlinePlus

    This upper abdominal CT scan shows multiple cysts in the liver, caused by dog tapeworm (echinococcus). Note the large circular cyst (seen on the left side of the screen) and multiple smaller cysts throughout ...

  15. Transverse section radionuclide scanning system

    DOEpatents

    Kuhl, David E.; Edwards, Roy Q.

    1976-01-01

    This invention provides a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format in order to permit accurate assessment of regional brain function localized in three-dimensions. High sensitivity crucially depends on overcoming the heretofore known raster type scanning, which requires back and forth detector movement involving dead-time or partial enclosure of the scan field. Accordingly, this invention provides a detector array having no back and forth movement by interlaced detectors that enclose the scan field and rotate as an integral unit around one axis of rotation in a slip ring that continuously transmits the detector data by means of laser emitting diodes, with the advantages that increased amounts of data can be continuously collected, processed and displayed with increased sensitivity according to a suitable computer program.

  16. MOEM scan engine for bar code reading and factory automation

    NASA Astrophysics Data System (ADS)

    Motamedi, M. Edward; Park, Sangtae; Melendes, Robert; Wang, A.; Andrews, Angus P.; Garcia-Nunez, Dawn S.; Jinar, Dan; Richardson, Patti D.; Studer, J.; Chen, J. K.; DeNatale, Jeffrey F.; Moranski, Jeffrey A.

    1998-03-01

    Rockwell is in the state of technology transfer to manufacturing of a micro-opto-electro-mechanical scan engine with superior scanning performance for bar code reading and factory automation. The scan engine consists of three main components: actuator, mirrors, and control electronics. The first two components are fabricated on a silicon cantilever beam while the control electronics are presently hybrid. The actuator comprises of a bimorph layer covered with two metal layers. The mirror has a large area (several mm2) and it is micromachined with a surface flatness better than (lambda) /2. Actuator scan-angles greater than 22 degree(s) with high repeatability in performance are achieved. The scan engine was integrated with an existing Rockwell commercial bar code reader/decoder and successfully proven to read a two-character code 39 bar code. The system was capable of decoding the 13-mil label at 360 scans per second with a 100% successful read performance. Environmental testing of the device indicates that the scanner can operate at elevated temperatures up to 70 degree(s)C with minor fluctuations in frequency and scan angle. The scanner has also gone through a lifetime cycle test and it has survived more than 8 billion cycles during a period of 18 months. To increase the yield and the performance level of the device, theoretical study as well as dynamic simulation by finite elements modeling have been investigated and will be reported separately.

  17. Lidar arc scan uncertainty reduction through scanning geometry optimization

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-01

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annual energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.

  18. Deconvolution of sinusoidal rapid EPR scans.

    PubMed

    Tseitlin, Mark; Rinard, George A; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2011-02-01

    In rapid scan EPR the magnetic field is scanned through the signal in a time that is short relative to electron spin relaxation times. Previously it was shown that the slow-scan lineshape could be recovered from triangular rapid scans by Fourier deconvolution. In this paper a general Fourier deconvolution method is described and demonstrated to recover the slow-scan lineshape from sinusoidal rapid scans. Since an analytical expression for the Fourier transform of the driving function for a sinusoidal scan was not readily apparent, a numerical method was developed to do the deconvolution. The slow scan EPR lineshapes recovered from rapid triangular and sinusoidal scans are in excellent agreement for lithium phthalocyanine, a trityl radical, and the nitroxyl radical, tempone. The availability of a method to deconvolute sinusoidal rapid scans makes it possible to scan faster than is feasible for triangular scans because of hardware limitations on triangular scans.

  19. Immersion ultrasonography: simultaneous A-scan and B-scan.

    PubMed

    Coleman, D J; Dallow, R L; Smith, M E

    1979-01-01

    In eyes with opaque media, ophthalmic ultrasound provides a unique source of information that can dramatically affect the course of patient management. In addition, when an ocular abnormality can be visualized, ultrasonography provides information that supplements and complements other diagnostic testing. It provides documentation and differentiation of abnormal states, such as vitreous hemorrhage and intraocular tumor, as well as differentiation of orbital tumors from inflammatory causes of exophthalmos. Additional capabilities of ultrasound are biometric determinations for calculation of intraocular lens implant powers and drug-effectiveness studies. Maximal information is derived from ultrasonography when A-scan and B-scan techniques are employed simultaneously. Flexibility of electronics, variable-frequency transducers, and the use of several different manual scanning patterns aid in detection and interpretation of results. The immersion system of ultrasonography provides these features optimally.

  20. Obstacles to Industrial Implementation of Scanning Systems

    Treesearch

    Anders Astrom; Olog Broman; John Graffman; Anders Gronlund; Armas Jappinene; Jari Luostarinen; Jan Nystrom; Daniel L. Schmoldt

    1998-01-01

    Initially the group discussed what is meant by scanning systems. An operational definition was adopted to consider scanning system in the current context to be nontraditional scanning. Where, traditional scanning is defined as scanning that has been industrially operational and relatively common for several years-a mature technology. For example,...

  1. Environmentally conscious patent histories

    NASA Astrophysics Data System (ADS)

    Crouch, Dennis D.; Crouch, Henry L.

    2004-02-01

    There is a need for investigators, legislators, and business leaders to understand the magnitude of innovation and discovery in the field of environmentally conscious technologies (ECTs). Knowledge of the "big picture" is important to providing a national and global account of actual environmental stewardship over the last twenty-five years. A recitation of the Environmental Protection Agency (EPA) supported Acts which have been enacted into law reveals one facet of the multifaceted dynamic of environmental consciousness. The popular discussion and debate, as well as partisan lobbying, which created the political forces leading to environmentally conscious legislation is another facet. A third facet is the corporate response to the threats and opportunities predicted by CEO"s and others through environmental scanning. This paper examines changes in environmentally conscious inventive effort by comparing data from United States Patents issued from 1976 through 2003. Patents are useful tool for measuring technological innovation because they are publicly available records of innovative activity. Although not all inventions result in patent applications, the monopoly rights granted on the invention give the inventor a strong incentive to obtain patents on any viable product or process. Among the results, we found a significant increase in patents relating to environmentally conscious products and processes during the period in question. Specifically, a dramatic increase in patent activity was seen for the decade of the 1990"s. Surprisingly, the patenting rate from 2000 to 2003 seems to have stabilized. Additionally public discussion of ECTs appears to have a positive impact on patent filings.

  2. Micromachined microscanners for optical scanning

    NASA Astrophysics Data System (ADS)

    Kiang, Meng-Hsiung; Solgaard, Olav; Muller, Richard S.; Lau, Kam Y.

    1997-04-01

    We present the design and fabrication of surface- micromachined electrostatic-comb driven microscanners that have high angular precision over a large scan angle. When used as resonant scanners, these mirrors have fast scan rates with very low operating power. We use polysilicon microhinges, which allow the micromirrors to be lifted out of the plane of the substrate after processing is completed, to create high-aspect-ratio optical surfaces with dimensions in the hundreds of micrometers s while taking advantage of the planar surface-micromachining processing technology. Microscanners that are capable of high-speed scanning over large scan angles with high precision have been fabricated. Application of these actuated micromirrors in laser barcode scanning and optical-fiber switches have been demonstrated. These single-mirror scanners can be combined to form more complicated microscanners such as a two-mirror, two-axis raster scanner that have a wide range of applications in areas such as medicine, displays, printing, data storage, and communications.

  3. EVALUATION OF COMPUTER-CONTROLLED SCANNING ELECTRON MICROSCOPY APPLIED TO AN AMBIENT URBAN AEROSOL SAMPLE

    EPA Science Inventory

    Concerns about the environmental and public health effects of particulate matter (PM) have stimulated interest in analytical techniques capable of measuring the size and chemical composition of individual aerosol particles. Computer-controlled scanning electron microscopy (CCSE...

  4. EVALUATION OF COMPUTER-CONTROLLED SCANNING ELECTRON MICROSCOPY APPLIED TO AN AMBIENT URBAN AEROSOL SAMPLE

    EPA Science Inventory

    Concerns about the environmental and public health effects of particulate matter (PM) have stimulated interest in analytical techniques capable of measuring the size and chemical composition of individual aerosol particles. Computer-controlled scanning electron microscopy (CCSE...

  5. Part A. The effect of the dimensions of learning model on the epistemological beliefs of students enrolled in general chemistry laboratory for post-baccalaureate pre-medical students, and, Part B. Environmental quality survey utilizing TRI Explorer and USGS water data and the analysis and characterization of particulate matter using scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Wallace, Darcie

    The first part of this dissertation deals with the dimension of learning model was developed by Robert Marzano in response to a comprehensive research and theory based framework on cognition and learning. The strategy forms a background that can be used in instruction, curriculum, and assessment. The experimental group was exposed to the model and the control group was exposed to normal instruction for three lab activities in a summer general chemistry laboratory. The students were assessed for content knowledge via review of pre-laboratory and post-laboratory questions and for attitudinal changes via the Epistemological Beliefs Assessment for Physical Science Students. The study indicates that there were no attitudinal changes between the two groups. On the other hand, the instructional model is a variable technique, and the experimental group performed better on the post laboratory questions. The second part of this dissertation presents the results of an environmental quality survey utilizing the Environmental Protection Agency's TRI Explorer database as well as the United States Geological Survey water quality database could provide a valuable tool for the assessment of land, air, and water contamination. The top three air, water, and land releases will be obtained from 1988 to 2002 for counties surrounding major cities in Tennessee. There was found to be a poor correlation between the TRI Explorer and USGS data for the counties in this study. This poor correlation may be due to the degradation pathways of the chemicals released. It should be noted that there has been a decrease in many of the compounds, such as chlorofluorocarbons, which have been addressed in legislation. Air samples were collected on mixed cellulose ester filters and silver membrane using a GS Cyclone particle size selector and analyzed using Scanning Electron Microscopy with Energy Dispersive X-ray Analysis. Unlike quartz filters, sample loss and change was minimal with the use of the mixed

  6. Studies in scanning probe microscopy

    NASA Astrophysics Data System (ADS)

    Sarid, Dror

    1995-06-01

    The following is a final report on our work in the field of Scanning Probe Microscopy (SPM), which has been funded by the AFOSR under Contract #F49620-92-J-0164. The AFOSR funding was instrumental in the establishment of a multi-lab facility at the Optical Sciences Center, which performs research in SPM using two ultrahigh vacuum (UHV) STM facilities, and several Atomic Force Microscopy (AFM) facilities. The fabrication and characterization work performed in the SPM Laboratory is supplemented by infrared (IR) spectroscopy, high resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM), available in other departments on campus. The report covers the following areas: (1) GaAs and CdSe Structures, (2) Optical Interactions on a nm and nsec Scales, (3) Fullerenes on Gold, (4) Fullerenes on MoS2, (5) Fullerenes on Si, (6) SiC, (7) Nanotubes, (8) Scanning Force Microscopy, and (9) Biology.

  7. Security scanning at 94GHz

    NASA Astrophysics Data System (ADS)

    Anderton, Rupert N.; Appleby, Roger; Beale, John E.; Coward, Peter R.; Price, Sean

    2006-05-01

    It is well known that millimetre waves can pass through clothing. In short range applications such as in the scanning of people for security purposes, operating at W band can be an advantage. The size of the equipment is decreased when compared to operation at Ka band and the equipments have similar performance. In this paper a W band mechanically scanned imager designed for imaging weapons and contraband hidden under clothing is discussed. This imager is based on a modified folded conical scan technology previously reported. In this design an additional optical element is added to give a Cassegrain configuration in image space. This increases the effective focal length and enables improved sampling of the image and provides more space for the receivers. This imager is constructed from low cost materials such as polystyrene, polythene and printed circuit board materials. The trade off between image spatial resolution and thermal sensitivity is discussed.

  8. Footwear scanning systems and methods

    DOEpatents

    Fernandes, Justin L.; McMakin, Douglas L.; Sheen, David M.; Tedeschi, Jonathan R.

    2017-07-25

    Methods and apparatus for scanning articles, such as footwear, to provide information regarding the contents of the articles are described. According to one aspect, a footwear scanning system includes a platform configured to contact footwear to be scanned, an antenna array configured to transmit electromagnetic waves through the platform into the footwear and to receive electromagnetic waves from the footwear and the platform, a transceiver coupled with antennas of the antenna array and configured to apply electrical signals to at least one of the antennas to generate the transmitted electromagnetic waves and to receive electrical signals from at least another of the antennas corresponding to the electromagnetic waves received by the others of the antennas, and processing circuitry configured to process the received electrical signals from the transceiver to provide information regarding contents within the footwear.

  9. Scanning laser polarimetry - a review.

    PubMed

    Da Pozzo, Stefano; Marchesan, Roberta; Ravalico, Giuseppe

    2009-01-01

    Glaucoma is a leading cause of irreversible blindness worldwide. Retinal ganglion cells and their axons represent the selective target of the disease. When visual function is still intact on standard automated perimetry and optic disc appearance is suspicious, an early diagnosis may be supported by the identification of a retinal nerve fibre layer (RNFL) defect in the peripapillary area. At present days, computer-based, real-time imaging of the peripapillary RNFL is available through instruments of easy use and with high levels of accuracy and reproducibility. Scanning laser polarimetry is performed by a confocal scanning laser ophthalmoscope with an integrated polarimeter (GDx-VCC). There is a considerable amount of scientific evidence about the role of this imaging technique for glaucoma diagnosis. The aim of this review is to describe the principles of operation, the examination procedure, the clinical role, the results of main diagnostic studies and the future development of the software for the scanning laser polarimetry.

  10. Nanobits: customizable scanning probe tips

    NASA Astrophysics Data System (ADS)

    Rajendra Kumar, R. T.; Hassan, S. U.; Sardan Sukas, O.; Eichhorn, V.; Krohs, F.; Fatikow, S.; Boggild, P.

    2009-09-01

    We present here a proof-of-principle study of scanning probe tips defined by planar nanolithography and integrated with AFM probes using nanomanipulation. The so-called 'nanobits' are 2-4 µm long and 120-150 nm thin flakes of Si3N4 or SiO2, fabricated by electron beam lithography and standard silicon processing. Using a microgripper they were detached from an array and fixed to a standard pyramidal AFM probe or alternatively inserted into a tipless cantilever equipped with a narrow slit. The nanobit-enhanced probes were used for imaging of deep trenches, without visible deformation, wear or dislocation of the tips of the nanobit after several scans. This approach allows an unprecedented freedom in adapting the shape and size of scanning probe tips to the surface topology or to the specific application.

  11. Nanobits: customizable scanning probe tips.

    PubMed

    Rajendra Kumar, R T; Hassan, S U; Sardan Sukas, O; Eichhorn, V; Krohs, F; Fatikow, S; Boggild, P

    2009-09-30

    We present here a proof-of-principle study of scanning probe tips defined by planar nanolithography and integrated with AFM probes using nanomanipulation. The so-called 'nanobits' are 2-4 microm long and 120-150 nm thin flakes of Si(3)N(4) or SiO(2), fabricated by electron beam lithography and standard silicon processing. Using a microgripper they were detached from an array and fixed to a standard pyramidal AFM probe or alternatively inserted into a tipless cantilever equipped with a narrow slit. The nanobit-enhanced probes were used for imaging of deep trenches, without visible deformation, wear or dislocation of the tips of the nanobit after several scans. This approach allows an unprecedented freedom in adapting the shape and size of scanning probe tips to the surface topology or to the specific application.

  12. Scanning Terahertz Heterodyne Imaging Systems

    NASA Technical Reports Server (NTRS)

    Siegel, Peter; Dengler, Robert

    2007-01-01

    Scanning terahertz heterodyne imaging systems are now at an early stage of development. In a basic scanning terahertz heterodyne imaging system, (see Figure 1) two far-infrared lasers generate beams denoted the local-oscillator (LO) and signal that differ in frequency by an amount, denoted the intermediate frequency (IF), chosen to suit the application. The LO beam is sent directly to a mixer as one of two inputs. The signal beam is focused to a spot on or in the specimen. After transmission through or reflection from the specimen, the beams are focused to a spot on a terahertz mixer, which extracts the IF outputs. The specimen is mounted on a translation stage, by means of which the focal spot is scanned across the specimen to build up an image.

  13. The combination of scanning electron and scanning probe microscopy

    SciTech Connect

    Sapozhnikov, I. D.; Gorbenko, O. M. Felshtyn, M. L.; Golubok, A. O.

    2016-06-17

    We suggest the SPM module to combine SEM and SPM methods for studying surfaces. The module is based on the original mechanical moving and scanning system. The examples of studies of the steel surface microstructure in both SEM and SPM modes are presented.

  14. Conically scanned holographic lidar telescope

    NASA Technical Reports Server (NTRS)

    Schwemmer, Geary (Inventor)

    1993-01-01

    An optical scanning device utilizing a source of optical energy such as laser light backscattered from the earth's atmosphere or transmitted outward as in a lidar, a rotating holographic optical element having an axis of rotation perpendicular to the plane of its substrate, and having a stationary focus which may or may not be located on its axis of rotation, with the holographic optical element diffracting the source of optical energy at an angle to its rotation axis enabling a conical scanning area and a motor for supporting and rotating the rotating holographic optical element, is described.

  15. Digital laser scanning fundus camera.

    PubMed

    Plesch, A; Klingbeil, U; Bille, J

    1987-04-15

    Imaging and documentation of the human retina for clinical diagnostics are conventionally achieved by classical optical methods. We designed a digital laser scanning fundus camera. The optoelectronical instrument is based on scanning laser illumination of the retina and a modified video imaging procedure. It is coupled to a digital image buffer and a microcomputer for image storage and processing. Aside from its high sensitivity the LSF incorporates new ophthalmic imaging methods like polarization differential contrast. We give design considerations as well as a description of the instrument and its performance.

  16. Research With Scanning Tip Microscopy

    DTIC Science & Technology

    1991-12-31

    08ro P noiwe bae?041Le Research With Scanning Tip Microscopy AFOSR-89-0498 V AUTHOS)i Professor Dror Sarid 7. PFOUImNG 00ANIZATION NAMEIS) AND...forces and (b) surfaces. UNCLASS UNCLASS UNCLASS UL FINAL REPORT TO THE AFOSR ൱-, to J4ti. r Aat io Research in Scanning Tip Microscopy Dror Sarid Dtst...microscopy have been used to investigate (a) forces and (b) surfaces. a. Forces 1. Dror Sarid , Douglas lams, Volker Weissenberger, and L. Stephen Bell

  17. Scanning color optical tomography (SCOT)

    PubMed Central

    Hosseini, Poorya; Sung, Yongjin; Choi, Youngwoon; Lue, Niyom; Yaqoob, Zahid; So, Peter

    2015-01-01

    We have developed an interferometric optical microscope that provides three-dimensional refractive index map of a specimen by scanning the color of three illumination beams. Our design of the interferometer allows for simultaneous measurement of the scattered fields (both amplitude and phase) of such a complex input beam. By obviating the need for mechanical scanning of the illumination beam or detection objective lens; the proposed method can increase the speed of the optical tomography by orders of magnitude. We demonstrate our method using polystyrene beads of known refractive index value and live cells. PMID:26367632

  18. High precision prism scanning system

    NASA Astrophysics Data System (ADS)

    García-Torales, G.; Flores, J. L.; Muñoz, Roberto X.

    2007-03-01

    Risley prisms are commonly used in continuous scanning manner. Each prism is capable of rotating separately about a common axis at different speeds. Scanning patterns are determined by the ratios of the wedge angles, the speed and direction of rotation of both prisms. The use of this system is conceptually simple. However, mechanical action in most applications becomes a challenge often solved by the design of complex control algorithms. We propose an electronic servomotor system that controls incremental and continuous rotations of the prisms wedges by means of an auto-tuning PID control using a Adaline Neural Network Algorithm, NNA.

  19. Lidar arc scan uncertainty reduction through scanning geometry optimization

    DOE PAGES

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; ...

    2016-04-13

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annualmore » energy production prediction. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30% of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. As a result, large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.« less

  20. CT scans through metal scanning technique versus hardware composition.

    PubMed

    Haramati, N; Staron, R B; Mazel-Sperling, K; Freeman, K; Nickoloff, E L; Barax, C; Feldman, F

    1994-01-01

    Streak artifact on CT scans of metal containing areas has been a long standing problem. Although several artifact reducing methods have been used to improve image quality, most have been limited by requiring specialized equipment or lengthy complex calculations that are not automated. Others have shown that increasing the beam energy results in increased thickness of metal that may be imaged by CT without severe image degradation. We have studied the image quality of bone surrounding metal both with titanium and cobalt-chrome prostheses using various scanning techniques. In a double blind fashion, 28 radiology residents and attendings were surveyed as to the best technique for imaging bone detail surrounding metal. A series of images was arranged of an implanted titanium prosthesis, a cobalt-chrome prosthesis and a pelvis repaired with stainless steel pelvic reconstruction plates. Scans were performed using three techniques: 120 kVp, 170 mA, 2 s, 360 degrees rotation, 140 kVp, 140 mA, 3 s, 360 degrees rotation, 140 kVp, 140 mA, 4 s, 420 degrees rotation. Titanium was superior to cobalt-chrome (p < .0001 Wilcoxon Signed Rank Test). No advantage was noted for higher kVp or increased scan arc of 420 degrees compared to the standard 360 degrees. Titanium allows improved bone detail surround the metal than CT cobalt-chrome. We have found no advantage to using either high kVp or a 420 degrees scan arc to improve the image quality of bone surrounded by metal.

  1. Error correction based on micro-scanning preprocessing for an optical micro-scanning thermal microscope imaging system

    NASA Astrophysics Data System (ADS)

    Gao, Meijing; Xu, Jie; Tan, Ailing; Zu, Zhenlong; Yang, Ming; Wang, Jingyuan

    2017-06-01

    In recent years, various thermal microscope imaging systems have been developed to meet the demands of micro-thermal analysis for large-scale integrated circuits, biomedical, science, and research fields. However, conventional thermal microscope imaging systems, which use cooled infrared detectors are heavy and expensive. In order to solve this problem, we developed a thermal microscope imaging system based on an uncooled infrared detector. However, the spatial resolution of the thermal microscope imaging system based on an uncooled infrared detector is low. With optical micro-scanning technology, the spatial resolution of the thermal microscope imaging system can be increased without increasing the detector dimension or reducing the detector unit size. In order to improve its spatial resolution, a micro-scanning system based on optical plate rotation was developed, and an optical microscanning thermal microscope imaging system was obtained after the integrated design. Due to environmental factors, mechanical vibration, alignment error and other factors, there is micro-scanning error in the designed micro-scanning thermal microscope imaging system. The four low-resolution images collected by micro-scanning thermal microscope imaging system are not standard down-sampled images. The quality of the image interpolated directly by four collected images is reduced and the performance of the micro-scanning system isn't fully exploited. Therefore, based on the proposed second-order oversampling reconstruction micro-scanning error correction algorithm and the new edge directed interpolation algorithm, a new micro-scanning error correction technique is proposed. Simulations and experiments show that the proposed technique can effectively reduce optical micro-scanning error, improve the systems spatial resolution and optimize the effect of the imaging system. It can be applied to other electro-optical imaging systems to improve their spatial resolution.

  2. Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber

    SciTech Connect

    Nguyen, Kayla X.; Holtz, Megan E.; Richmond-Decker, Justin; Muller, David A.

    2016-07-25

    Abstract

    A long-standing goal of electron microscopy has been the high-resolution characterization of specimens in their native environment. However, electron optics require high vacuum to maintain an unscattered and focused probe, a challenge for specimens requiring atmospheric or liquid environments. Here, we use an electron-transparent window at the base of a scanning electron microscope’s objective lens to separate column vacuum from the specimen, enabling imaging under ambient conditions, without a specimen vacuum chamber. We demonstrate in-air imaging of specimens at nanoscale resolution using backscattered scanning electron microscopy (airSEM) and scanning transmission electron microscopy. We explore resolution and contrast using Monte Carlo simulations and analytical models. We find that nanometer-scale resolution can be obtained at gas path lengths up to 400μm, although contrast drops with increasing gas path length. As the electron-transparent window scatters considerably more than gas at our operating conditions, we observe that the densities and thicknesses of the electron-transparent window are the dominant limiting factors for image contrast at lower operating voltages. By enabling a variety of detector configurations, the airSEM is applicable to a wide range of environmental experiments including the imaging of hydrated biological specimens andin situchemical and electrochemical processes.

  3. Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber.

    PubMed

    Nguyen, Kayla X; Holtz, Megan E; Richmond-Decker, Justin; Muller, David A

    2016-08-01

    A long-standing goal of electron microscopy has been the high-resolution characterization of specimens in their native environment. However, electron optics require high vacuum to maintain an unscattered and focused probe, a challenge for specimens requiring atmospheric or liquid environments. Here, we use an electron-transparent window at the base of a scanning electron microscope's objective lens to separate column vacuum from the specimen, enabling imaging under ambient conditions, without a specimen vacuum chamber. We demonstrate in-air imaging of specimens at nanoscale resolution using backscattered scanning electron microscopy (airSEM) and scanning transmission electron microscopy. We explore resolution and contrast using Monte Carlo simulations and analytical models. We find that nanometer-scale resolution can be obtained at gas path lengths up to 400 μm, although contrast drops with increasing gas path length. As the electron-transparent window scatters considerably more than gas at our operating conditions, we observe that the densities and thicknesses of the electron-transparent window are the dominant limiting factors for image contrast at lower operating voltages. By enabling a variety of detector configurations, the airSEM is applicable to a wide range of environmental experiments including the imaging of hydrated biological specimens and in situ chemical and electrochemical processes.

  4. Improvement of CAT scanned images

    NASA Technical Reports Server (NTRS)

    Roberts, E., Jr.

    1980-01-01

    Digital enhancement procedure improves definition of images. Tomogram is generated from large number of X-ray beams. Beams are collimated and small in diameter. Scanning device passes beams sequentially through human subject at many different angles. Battery of transducers opposite subject senses attenuated signals. Signals are transmitted to computer where they are used in construction of image on transverse plane through body.

  5. A CAT scan for cells

    SciTech Connect

    2009-01-01

    Recently, a team of scientists from Berkeley Lab, Stanford University, and the University of California, San Francisco used Berkeley Lab's National Center for X-ray Tomography to capture the changes that occur when Candida albicans is exposed to a new and promising antifungal therapy. http://newscenter.lbl.gov/feature-stories/2009/12/10/cat-scan-cells/

  6. Infrared Scanning For Electrical Maintenance

    NASA Astrophysics Data System (ADS)

    Eisenbath, Steven E.

    1983-03-01

    Given the technological age that we have now entered, the purpose of this paper is to relate how infrared scanning can be used for an electrical preventative maintenance program. An infrared scanner is able to produce an image because objects give off infrared radiation in relationship to their temperature. Most electrical problems will show up as an increase in temperature, thereby making the infrared scanner a useful preventative maintenance tool. Because of the sensitivity of most of the scanners, .1 to .2 of a degree, virtually all electrical problems can be pinpointed long before they become a costly failure. One of the early uses of infrared scanning was to check the power company's electrical distribution system. Most of this was performed via aircraft or truck mounted scanning devices which necessitated its semi-permanent mounting. With the advent of small hand held infrared imagers, along with more portability of the larger systems, infrared scanning has gained more popularity in checking electrical distribution systems. But the distribution systems are now a scaled down model, mainly the in-plant electrical systems. By in-plant, I mean any distribution of electricity; once it leaves the power company's grid. This can be in a hospital, retail outlet, warehouse or manufacturing facility.

  7. Improvement of CAT scanned images

    NASA Technical Reports Server (NTRS)

    Roberts, E., Jr.

    1980-01-01

    Digital enhancement procedure improves definition of images. Tomogram is generated from large number of X-ray beams. Beams are collimated and small in diameter. Scanning device passes beams sequentially through human subject at many different angles. Battery of transducers opposite subject senses attenuated signals. Signals are transmitted to computer where they are used in construction of image on transverse plane through body.

  8. Line-scanning laser ophthalmoscope

    NASA Astrophysics Data System (ADS)

    Hammer, Daniel X.; Ferguson, R. Daniel; Ustun, Teoman E.; Bigelow, Chad E.; Iftimia, Nicusor V.; Webb, Robert H.

    2006-07-01

    Scanning laser ophthalmoscopy (SLO) is a powerful imaging tool with specialized applications limited to research and ophthalmology clinics due in part to instrument size, cost, and complexity. Conversely, low-cost retinal imaging devices have limited capabilities in screening, detection, and diagnosis of diseases. To fill the niche between these two, a hand-held, nonmydriatic line-scanning laser ophthalmoscope (LSLO) is designed, constructed, and tested on normal human subjects. The LSLO has only one moving part and uses a novel optical approach to produce wide-field confocal fundus images. Imaging modes include multiwavelength illumination and live stereoscopic imaging with a split aperture. Image processing and display functions are controlled with two stacked prototype compact printed circuit boards. With near shot-noise limited performance, the digital LSLO camera requires low illumination power (<500 µW) at near-infrared wavelengths. The line-scanning principle of operation is examined in comparison to SLO and other imaging modes. The line-scanning approach produces high-contrast confocal images with nearly the same performance as a flying-spot SLO. The LSLO may significantly enhance SLO utility for routine use by ophthalmologists, optometrists, general practitioners, and also emergency medical personnel and technicians in the field for retinal disease detection and other diverse applications.

  9. Scanning tunneling microscope nanoetching method

    DOEpatents

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

    1990-01-01

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

  10. Thermal radiation scanning tunnelling microscopy.

    PubMed

    De Wilde, Yannick; Formanek, Florian; Carminati, Rémi; Gralak, Boris; Lemoine, Paul-Arthur; Joulain, Karl; Mulet, Jean-Philippe; Chen, Yong; Greffet, Jean-Jacques

    2006-12-07

    In standard near-field scanning optical microscopy (NSOM), a subwavelength probe acts as an optical 'stethoscope' to map the near field produced at the sample surface by external illumination. This technique has been applied using visible, infrared, terahertz and gigahertz radiation to illuminate the sample, providing a resolution well beyond the diffraction limit. NSOM is well suited to study surface waves such as surface plasmons or surface-phonon polaritons. Using an aperture NSOM with visible laser illumination, a near-field interference pattern around a corral structure has been observed, whose features were similar to the scanning tunnelling microscope image of the electronic waves in a quantum corral. Here we describe an infrared NSOM that operates without any external illumination: it is a near-field analogue of a night-vision camera, making use of the thermal infrared evanescent fields emitted by the surface, and behaves as an optical scanning tunnelling microscope. We therefore term this instrument a 'thermal radiation scanning tunnelling microscope' (TRSTM). We show the first TRSTM images of thermally excited surface plasmons, and demonstrate spatial coherence effects in near-field thermal emission.

  11. Phase multiplying electronic scanning array

    NASA Technical Reports Server (NTRS)

    Seaton, A. F.

    1969-01-01

    Scanning array was designed with properties of low RF loss and phase control. The array consists of a series of special waveguides, hybrids made up of two variable reactance branch arms for input signals, an edge slot for the difference port, and a sum arm for the unradiated signal.

  12. Scanning Quantum Cryogenic Atom Microscope

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Kollár, Alicia J.; Taylor, Stephen F.; Turner, Richard W.; Lev, Benjamin L.

    2017-03-01

    Microscopic imaging of local magnetic fields provides a window into the organizing principles of complex and technologically relevant condensed-matter materials. However, a wide variety of intriguing strongly correlated and topologically nontrivial materials exhibit poorly understood phenomena outside the detection capability of state-of-the-art high-sensitivity high-resolution scanning probe magnetometers. We introduce a quantum-noise-limited scanning probe magnetometer that can operate from room-to-cryogenic temperatures with unprecedented dc-field sensitivity and micron-scale resolution. The Scanning Quantum Cryogenic Atom Microscope (SQCRAMscope) employs a magnetically levitated atomic Bose-Einstein condensate (BEC), thereby providing immunity to conductive and blackbody radiative heating. The SQCRAMscope has a field sensitivity of 1.4 nT per resolution-limited point (approximately 2 μ m ) or 6 nT /√{Hz } per point at its duty cycle. Compared to point-by-point sensors, the long length of the BEC provides a naturally parallel measurement, allowing one to measure nearly 100 points with an effective field sensitivity of 600 pT /√{Hz } for each point during the same time as a point-by-point scanner measures these points sequentially. Moreover, it has a noise floor of 300 pT and provides nearly 2 orders of magnitude improvement in magnetic flux sensitivity (down to 10-6 Φ0/√{Hz } ) over previous atomic probe magnetometers capable of scanning near samples. These capabilities are carefully benchmarked by imaging magnetic fields arising from microfabricated wire patterns in a system where samples may be scanned, cryogenically cooled, and easily exchanged. We anticipate the SQCRAMscope will provide charge-transport images at temperatures from room temperature to 4 K in unconventional superconductors and topologically nontrivial materials.

  13. Environmental Management.

    ERIC Educational Resources Information Center

    Bandhu, Desh, Ed.

    The Indian Environmental Society, in association with the International Programme on Environmental Management Education, organized two seminars on World Environment Day and Environmental Impact Assessment during June 1980. A large number of papers on various aspects of environmental management were presented during the seminars. The papers…

  14. Environmental Management.

    ERIC Educational Resources Information Center

    Bandhu, Desh, Ed.

    The Indian Environmental Society, in association with the International Programme on Environmental Management Education, organized two seminars on World Environment Day and Environmental Impact Assessment during June 1980. A large number of papers on various aspects of environmental management were presented during the seminars. The papers…

  15. Ultrasonic scanning of multilayer ceramic chip capacitors

    NASA Technical Reports Server (NTRS)

    Bradley, F. N.

    1981-01-01

    Ultrasonic scanning is compared to neutron radiography and scanning laser acoustic microscopy (SLAM). Data show that SLAM and ultrasonic scanning evaluations are in good agreement. There is poor agreement between N-ray and both ultrasonic techniques because N-ray is insensitive to all but the grossest delaminations. Statistical analysis show a good correlation between ultrasonic scanning and destructive physical analysis.

  16. Differential Multiphoton Laser Scanning Microscopy

    SciTech Connect

    Field, Jeffrey J.; Sheetz, Kraig E.; Chandler, Eric V.; Hoover, Erich E.; Young, Michael D.; Ding, Shi-you; Sylvester, Anne W.; Kleinfeld, David; Squier, Jeff A.

    2012-01-01

    Multifocal multiphoton laser scanning microscopy (mfMPLSM) in the biological and medical sciences has the potential to become a ubiquitous tool for obtaining high-resolution images at video rates. While current implementations of mfMPLSM achieve very high frame rates, they are limited in their applicability to essentially those biological samples that exhibit little or no scattering. In this paper, we report on a method for mfMPLSM in which whole-field detection with a single detector, rather than detection with a matrix of detectors, such as a charge-coupled device (CCD) camera, is implemented. This advance makes mfMPLSM fully compatible for use in imaging through scattering media. Further, we demonstrate that this method makes it possible to simultaneously obtain multiple images and view differences in excitation parameters in a single scan of the specimen.

  17. A spectrum scanning Stokes polarimeter

    NASA Astrophysics Data System (ADS)

    Baur, T. G.; House, L. L.; Hull, H. K.

    1980-02-01

    A photoelectric polarimeter for measuring line profiles in all four Stokes parameters has been built and operates on the SPO 40 cm coronagraph in a joint project with Sacramento Peak Observatory. A description of the optical and electronic systems and the calibration scheme is presented. Performance parameters determined from observations are also given. The polarimeter package consisting of a pair of KDP's, a quarter wave plate, and a polarizing beam splitter is located at the prime focus of the coronagraph. Modulation of the KDP's encodes polarization information into intensity signals that are electronically detected. The scanning of the spectrum, accomplished by rotating the grating, permits Stokes line profiles to be recorded on magnetic tape for processing. The instrument can be used to scan any line from 3900 to 7000 A with a spectral resolution of 0.01 A. Polarizations as small as 0.001% are detectable. The polarimeter and observing system are computer controlled.

  18. Vertically scanned laser sheet microscopy.

    PubMed

    Dong, Di; Arranz, Alicia; Zhu, Shouping; Yang, Yujie; Shi, Liangliang; Wang, Jun; Shen, Chen; Tian, Jie; Ripoll, Jorge

    2014-01-01

    Laser sheet microscopy is a widely used imaging technique for imaging the three-dimensional distribution of a fluorescence signal in fixed tissue or small organisms. In laser sheet microscopy, the stripe artifacts caused by high absorption or high scattering structures are very common, greatly affecting image quality. To solve this problem, we report here a two-step procedure which consists of continuously acquiring laser sheet images while vertically displacing the sample, and then using the variational stationary noise remover (VSNR) method to further reduce the remaining stripes. Images from a cleared murine colon acquired with a vertical scan are compared with common stitching procedures demonstrating that vertically scanned light sheet microscopy greatly improves the performance of current light sheet microscopy approaches without the need for complex changes to the imaging setup and allows imaging of elongated samples, extending the field of view in the vertical direction.

  19. Scanning Probe Microscopy Markup Language

    NASA Astrophysics Data System (ADS)

    Bolhuis, T.; Pasop, J. R.; Abelmann, L.; Lodder, J. C.

    2003-12-01

    The numerous, proprietary file formats for Scanning Probe Microscopy (SPM) have caused problems in the field of both off-line quantitative, data analysis and comparison, as well as long-term archiving of measurement results. Because of the eminent roll SPM's are playing in the multidisciplinary scientific world of today, an open, XML-based, standard SPM data format, called Scanning Probe Microscopy Markup Language (SPML) is proposed. XML (eXtensible Markup Language) has proven to be well applicable for standardized, structured, scientific data formats in many other disciplines. The structure of SPML will be explained briefly. The versatility of SPML as well as the possibilities of documenting, publishing, searching and exchanging SPM-data will be shown in examples. This paper gives an overview of the proposed data format, while the complete description can be found at http://spml.net.

  20. Scanned Laser Illuminator/Receiver

    DTIC Science & Technology

    1976-11-01

    matching high sensitivity, high resolution receiver. A CW- pumped Nd:YAG laser operated in a pulsed mode and providing a fan-shaped illumination beam...greatly improve the linearity of the scanner and to permit variable scan rate (non-resonant) operation. A cw- pumped NdiYAG laser is used as the...illustrate parallel development of the PIN diode /CCD sensor hybrid and the 100W laser . Al- though a detailed cost analysis for procurement of this large

  1. Scanning phononic lattices with ultrasound

    SciTech Connect

    Vines, R.E.; Wolfe, J.P.; Every, A.V.

    1999-11-01

    A method for probing the elastic properties of newly developed periodic structures using acoustic waves is introduced. Highly anisotropic transmission of surface acoustic waves is observed by continuously scanning the wave vector angle. Preliminary models of wave propagation through multilayers and two-dimensional lattices explain some of the experimental features, while other features can be attributed to the resonant excitation of interface waves. {copyright} {ital 1999} {ital The American Physical Society}

  2. Differential scanning calorimetry of coal

    NASA Technical Reports Server (NTRS)

    Gold, P. I.

    1978-01-01

    Differential scanning calorimetry studies performed during the first year of this project demonstrated the occurrence of exothermic reactions associated with the production of volatile matter in or near the plastic region. The temperature and magnitude of the exothermic peak were observed to be strongly affected by the heating rate, sample mass and, to a lesser extent, by sample particle size. Thermal properties also were found to be influenced by oxidation of the coal sample due to weathering effects.

  3. Cloud Top Scanning radiometer (CTS)

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A scanning radiometer to be used for measuring cloud radiances in each of three spectral regions is described. Significant features incorporated in the Cloud Top Scanner design are: (1) flexibility and growth potential through use of easily replaceable modular detectors and filters; (2) full aperture, multilevel inflight calibration; (3) inherent channel registration through employment of a single shared field stop; and (4) radiometric sensitivity margin in a compact optical design through use of Honeywell developed (Hg,Cd)Te detectors and preamplifiers.

  4. Mechanically scanned deployable antenna study

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The conceptual design of a Mechanically Scanned Deployable Antenna which is launched by the STS (Space Shuttle) to provide radiometric brightness temperature maps of the Earth and oceans at selected frequency bands in the frequency range of 1.4 GHz to 11 GHz is presented. Unlike previous scanning radiometric systems, multiple radiometers for each frequency are required in order to fill in the resolution cells across the swath created by the 15 meter diameter spin stabilized system. This multiple beam radiometric system is sometimes designated as a ""whiskbroom'' system in that it combines the techniques of the scanning and ""pushbroom'' type systems. The definition of the feed system including possible feed elements and location, determination of the fundamental reflector feed offset geometry including offset angles and f/D ratio, preliminary estimates of the beam efficiency of the feed reflector system, a summary of reflector mesh losses at the proposed radiometric frequency bands, an overall conceptual configuration design and preliminary structural and thermal analyses are included.

  5. MAMMALIAN APOPTOSIS IN WHOLE NEONATAL OVARIES USING CONFOCAL LASER SCANNING MICROSCOPY

    EPA Science Inventory

    MAMMALIAN APOPTOSIS IN WHOLE NEONATAL OVARIES USING CONFOCAL LASER SCANNING MICROSCOPY

    Robert M. Zucker Susan C. Jeffery and Sally D. Perreault

    Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Prot...

  6. MAMMALIAN APOPTOSIS IN WHOLE NEONATAL OVARIES USING CONFOCAL LASER SCANNING MICROSCOPY

    EPA Science Inventory

    MAMMALIAN APOPTOSIS IN WHOLE NEONATAL OVARIES USING CONFOCAL LASER SCANNING MICROSCOPY

    Robert M. Zucker Susan C. Jeffery and Sally D. Perreault

    Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Prot...

  7. Quantum inertia stops superposition: Scan Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Gato-Rivera, Beatriz

    2017-08-01

    Scan Quantum Mechanics is a novel interpretation of some aspects of quantum mechanics in which the superposition of states is only an approximate effective concept. Quantum systems scan all possible states in the superposition and switch randomly and very rapidly among them. A crucial property that we postulate is quantum inertia, that increases whenever a constituent is added, or the system is perturbed with all kinds of interactions. Once the quantum inertia Iq reaches a critical value Icr for an observable, the switching among its different eigenvalues stops and the corresponding superposition comes to an end, leaving behind a system with a well defined value of that observable. Consequently, increasing the mass, temperature, gravitational strength, etc. of a quantum system increases its quantum inertia until the superposition of states disappears for all the observables and the system transmutes into a classical one. Moreover, the process could be reversible. Entanglement can only occur between quantum systems because an exact synchronization between the switchings of the systems involved must be established in the first place and classical systems do not have any switchings to start with. Future experiments might determine the critical inertia Icr corresponding to different observables, which translates into a critical mass Mcr for fixed environmental conditions as well as critical temperatures, critical electric and magnetic fields, etc. In addition, this proposal implies a new radiation mechanism from astrophysical objects with strong gravitational fields, giving rise to non-thermal synchrotron emission, that could contribute to neutron star formation. Superconductivity, superfluidity, Bose-Einstein condensates, and any other physical phenomena at very low temperatures must be reanalyzed in the light of this interpretation, as well as mesoscopic systems in general.

  8. Preoperative nuclear scans in patients with melanoma

    SciTech Connect

    Au, F.C.; Maier, W.P.; Malmud, L.S.; Goldman, L.I.; Clark, W.H. Jr.

    1984-05-15

    One hundred forty-one liver scans, 137 brain scans, and 112 bone scans were performed in 192 patients with clinical Stage 1 melanoma. One liver scan was interpreted as abnormal; liver biopsy of that patient showed no metastasis. There were 11 suggestive liver scans; three of the patients with suggestive liver scans had negative liver biopsies. The remaining eight patients were followed from 4 to 6 years and none of those patients developed clinical evidence of hepatic metastases. All of the brain scans were normal. Five patients had suggestive bone scans and none of those patients had manifested symptoms of osseous metastases with a follow-up of 2 to 4.5 years. This study demonstrates that the use of preoperative liver, brain and bone scan in the evaluation of patients with clinical Stage 1 melanoma is virtually unproductive.

  9. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... converters used with scanning receivers. (a) Except as provided in paragraph (c) of this section, scanning... in paragraph (c) of this section, scanning receivers shall reject any signals from the Cellular.... (c) Scanning receivers and frequency converters designed or marketed for use with scanning...

  10. Environmental leadership

    SciTech Connect

    Langton, S.

    1984-01-01

    A resource for professional and volunteer managers of environmental organizations, this book provides instruction for raising funds, writing proposals, lobbying, utilizing the media, and maximizing human resources. Langton also assesses the environmental movement's future.

  11. Environmental Modeling

    EPA Pesticide Factsheets

    EPA's modeling community is working to gain insights into certain parts of a physical, biological, economic, or social system by conducting environmental assessments for Agency decision making to complex environmental issues.

  12. Environmental Measurement

    EPA Pesticide Factsheets

    Environmental measurement is any data collection activity involving the assessment of chemical, physical, or biological factors in the environment which affect human health. Learn more about these programs and tools that aid in environmental decisions

  13. Environmental Geology

    ERIC Educational Resources Information Center

    Dunn, James R.

    1977-01-01

    Discusses ways that geologic techniques can be used to help evaluate our environment, make economic realities and environmental requirements more compatible, and expand the use of geology in environmental analyses. (MLH)

  14. Environmental Geophysics

    EPA Pesticide Factsheets

    The Environmental Geophysics website features geophysical methods, terms and references; forward and inverse geophysical models for download; and a decision support tool to guide geophysical method selection for a variety of environmental applications.

  15. Scanning Miniature Microscopes without Lenses

    NASA Technical Reports Server (NTRS)

    Wang, Yu

    2009-01-01

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

  16. Scanning probe microscopy in catalysis.

    PubMed

    Yeung, King Lun; Yao, Nan

    2004-09-01

    This review discusses the recent progress in the application of scanning probe microscopy (SPM) in catalysis. SPM proves to be an invaluable technique for imaging catalytic surfaces and interfaces. Most SPM research is related to the structural and morphological transformation associated with catalyst preparation and use. Real-time SPM observation of surface dynamics including adsorption, diffusion and reaction, provides invaluable insights to the mechanism of catalysis. SPM is also used to shape and manipulate surfaces and surface processes. Fabrication of nanostructured catalysts, direct manipulation of adsorbed atoms and molecules and tip-mediated reactions are some examples of new SPM approach in catalyst research.

  17. High Resolution Scanning Reflectarray Antenna

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R. (Inventor); Miranda, Felix A. (Inventor)

    2000-01-01

    The present invention provides a High Resolution Scanning Reflectarray Antenna (HRSRA) for the purpose of tracking ground terminals and space craft communication applications. The present invention provides an alternative to using gimbaled parabolic dish antennas and direct radiating phased arrays. When compared to a gimbaled parabolic dish, the HRSRA offers the advantages of vibration free steering without incurring appreciable cost or prime power penalties. In addition, it offers full beam steering at a fraction of the cost of direct radiating arrays and is more efficient.

  18. Electronic imaging and scanning system

    NASA Technical Reports Server (NTRS)

    Jain, A.

    1977-01-01

    Frequency-variable illumination has been used previously to provide high resolution imaging in one dimension. The paper extends the results on this imaging by frequency scanning to derive the expression for a two-dimensional image. This is the Fourier transformation, with respect to the angle and frequency of illumination, of the electric field detected in the far-field region of the object. The case is considered of a rough object and it is shown that for roughness finer than the resolution of the imaging system, the image has a granular appearance corresponding to the classical speckle effect. Large scale phase perturbations lead to the elevation displacement effect.

  19. Aperture scanning Fourier ptychographic microscopy

    PubMed Central

    Ou, Xiaoze; Chung, Jaebum; Horstmeyer, Roarke; Yang, Changhuei

    2016-01-01

    Fourier ptychographic microscopy (FPM) is implemented through aperture scanning by an LCOS spatial light modulator at the back focal plane of the objective lens. This FPM configuration enables the capturing of the complex scattered field for a 3D sample both in the transmissive mode and the reflective mode. We further show that by combining with the compressive sensing theory, the reconstructed 2D complex scattered field can be used to recover the 3D sample scattering density. This implementation expands the scope of application for FPM and can be beneficial for areas such as tissue imaging and wafer inspection. PMID:27570705

  20. Environmental Professionals

    DTIC Science & Technology

    1992-08-01

    schools as business are realizing the need to improve environmental literacy among their students. As recently as 1986, American business schools were...devoid of courses on how to manage environmental issties. The current trend, however, has been for university business schools to include environmental...Approximately 25 U.S. business schools now teach environmental management. The Corporate Conservation Council. an arm of the National Wildlife Federation

  1. Environmental Analysis

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Burns & McDonnell Engineering's environmental control study is assisted by NASA's Computer Software Management and Information Center's programs in environmental analyses. Company is engaged primarily in design of such facilities as electrical utilities, industrial plants, wastewater treatment systems, dams and reservoirs and aviation installations. Company also conducts environmental engineering analyses and advises clients as to the environmental considerations of a particular construction project. Company makes use of many COSMIC computer programs which have allowed substantial savings.

  2. Environmental Education.

    ERIC Educational Resources Information Center

    Bandhu, Desh, Ed.; Aulakh, G. S., Ed.

    In India, environmental education (EE) is introduced at various levels. Goals of this country's EE programs include: improving the quality of environment to create awareness among the people on environmental problems and conservation; developing skills to solve environmental problems; creating the necessary atmosphere for citizen participation in…

  3. Environmental Technology.

    ERIC Educational Resources Information Center

    Columbus State Community Coll., OH.

    This document contains materials developed for and about the environmental technology tech prep program of the South-Western City Schools in Ohio. Part 1 begins with a map of the program, which begins with an environmental science technology program in grades 11 and 12 that leads to entry-level employment or a 2-year environmental technology…

  4. Environmental Education.

    ERIC Educational Resources Information Center

    Bandhu, Desh, Ed.; Aulakh, G. S., Ed.

    In India, environmental education (EE) is introduced at various levels. Goals of this country's EE programs include: improving the quality of environment to create awareness among the people on environmental problems and conservation; developing skills to solve environmental problems; creating the necessary atmosphere for citizen participation in…

  5. Environmental awareness

    SciTech Connect

    Not Available

    1992-12-31

    This brochure is intended to provide guidance on environmental regulations to National Fertilizer and Environmental Research Center (NFERC) employees. Topics covered include: handling of hazardous materials, disposal of hazardous wastes, spill prevention and remediation, pcb contamination, pesticide use, asbestos remediation, solid waste disposal, and environmental laws. Safety aspects are emphasized.

  6. Breast ultrasound scans - surgeons' expectations.

    PubMed

    Bednarski, Piotr; Dobruch-Sobczak, Katarzyna; Chrapowicki, Eryk; Jakubowski, Wiesław

    2015-06-01

    Recent years have witnessed a dynamic development of mammary gland imaging techniques, particularly ultrasonography and magnetic resonance imaging. A challenge related to these studies is the increase in the precision of the anatomical assessment of breast, particularly for early detection of subclinical lesions, performance of ultrasound- guided biopsy procedures, and accurate preoperative location of pathological lesions so as to optimize the surgical treatment. Ultrasound imaging is a primary and baseline diagnostic procedure the patient with suspected pathological lesions within breast is referred to by the surgeon. Lesions visualized in ultrasound scans are classified according to the BI-RADS US assessment categories. The successive categories (2 through 6) encompass individual pathological lesions, estimating the risk of malignancy and provide guidelines for further diagnostic and therapeutic management. This article described the important aspects of ultrasonographic imaging of focal lesions within the breasts as significant from the standpoint of surgical treatment of patients falling within BI-RADS US categories 3, 4, 5, and 6. Attention is drawn to the importance of ultrasound scans in the assessment of axillary fossa lymph nodes before the decision regarding the surgical treatment.

  7. Schistosomiasis collection at NHM (SCAN)

    PubMed Central

    2012-01-01

    Background The Natural History Museum (NHM) is developing a repository for schistosomiasis-related material, the Schistosomiasis Collection at NHM (SCAN) as part of its existing Wolfson Wellcome Biomedical Laboratory (WWBL). This is timely because a major research and evaluation effort to understand control and move towards elimination of schistosomiasis in Africa has been initiated by the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), resulting in the collection of many important biological samples, including larval schistosomes and snails. SCAN will collaborate with a number of research groups and control teams and the repository will acquire samples relevant to both immediate and future research interest. The samples collected through ongoing research and field activities, WWBL’s existing collections, and other acquisitions will be maintained over the long term and made available to the global research community for approved research purposes. Goals include: · Consolidation of the existing NHM schistosome and snail collections and transfer of specimens into suitable long-term storage systems for DNA retrieval, · Long-term and stable storage of specimens collected as part of on going field programmes initially in Africa especially relating to the SCORE research programmes, · Provision of access to snail and schistosome collections for approved research activities. PMID:22943137

  8. Three-dimensional scanning confocal laser microscope

    DOEpatents

    Anderson, R. Rox; Webb, Robert H.; Rajadhyaksha, Milind

    1999-01-01

    A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.

  9. Defect scanning technology in the works

    Treesearch

    Philip A. Araman; R. Conners

    1994-01-01

    This article describes the defect scanning technology being developed by Virginia Tech and U.S. Forest Service scientists in Blacksburg, Virginia to scan full sized hardwood lumber at industrial speeds.

  10. Optical analysis of scanning microstereolithography systems

    NASA Astrophysics Data System (ADS)

    Deshmukh, Suhas P.; Dubey, Shashikant; Gandhi, P. S.

    2006-01-01

    Microstereolithography (MSL) is rapidly developing technique for micro-fabrication. Vector-by-vector scanning MSL has a potential to create true 3D micro-devices as compared to mostly planar (2D-2 1/2 D) devices fabricated by conventional MEMS techniques. Previous literature shows two different scanning methods:(1) Galvanomirror scanning, (2) Photoreactor tank scanning. Galvanomirror scanning technique has higher fabrication speed but poor resolution because of defocusing of laser spot on the resin surface. Photo-reactor tank scanning has higher resolution but produces a wavy structures and limited speed of fabrication. This paper proposes and develops an offaxis lens scanning technique for MSL and carries out optical analysis to compare its performance with the existing techniques mentioned above. The comparison clearly demonstrates improved performance with the proposed offaxis lens scanning technique.

  11. Rapid-scan EPR of immobilized nitroxides.

    PubMed

    Yu, Zhelin; Quine, Richard W; Rinard, George A; Tseitlin, Mark; Elajaili, Hanan; Kathirvelu, Velavan; Clouston, Laura J; Boratyński, Przemysław J; Rajca, Andrzej; Stein, Richard; Mchaourab, Hassane; Eaton, Sandra S; Eaton, Gareth R

    2014-10-01

    X-band electron paramagnetic resonance spectra of immobilized nitroxides were obtained by rapid scan at 293 K. Scan widths were 155 G with 13.4 kHz scan frequency for (14)N-perdeuterated tempone and for T4 lysozyme doubly spin labeled with an iodoacetamide spirocyclohexyl nitroxide and 100 G with 20.9 kHz scan frequency for (15)N-perdeuterated tempone. These wide scans were made possible by modifications to our rapid-scan driver, scan coils made of Litz wire, and the placement of highly conducting aluminum plates on the poles of a Bruker 10″ magnet to reduce resistive losses in the magnet pole faces. For the same data acquisition time, the signal-to-noise for the rapid-scan absorption spectra was about an order of magnitude higher than for continuous wave first-derivative spectra recorded with modulation amplitudes that do not broaden the lineshapes.

  12. Can Scans Predict Some Autism Cases?

    MedlinePlus

    ... Services. More Health News on Autism Spectrum Disorder MRI Scans Recent Health News Related MedlinePlus Health Topics Autism Spectrum Disorder MRI Scans About MedlinePlus Site Map FAQs Customer Support Get ...

  13. Three-dimensional scanning confocal laser microscope

    DOEpatents

    Anderson, R. Rox; Webb, Robert H.; Rajadhyaksha, Milind

    1999-01-01

    A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.

  14. Rapid-Scan EPR of Immobilized Nitroxides

    PubMed Central

    Yu, Zhelin; Quine, Richard W.; Rinard, George A.; Tseitlin, Mark; Elajaili, Hanan; Kathirvelu, Velavan; Clouston, Laura J.; Boratyński, Przemysław J.; Rajca, Andrzej; Stein, Richard; Mchaourab, Hassane; Eaton, Sandra S.; Eaton, Gareth R.

    2014-01-01

    X-band electron paramagnetic resonance spectra of immobilized nitroxides were obtained by rapid scan at 293 K. Scan widths were 155 G with 13.4 kHz scan frequency for 14N-perdeuterated tempone and for T4 lysozyme doubly spin labeled with an iodoacetamide spirocyclohexyl nitroxide and 100 G with 20.9 kHz scan frequency for 15N-perdeuterated tempone. These wide scans were made possible by modifications to our rapid-scan driver, scan coils made of Litz wire, and the placement of highly conducting aluminum plates on the poles of a Bruker 10" magnet to reduce resistive losses in the magnet pole faces. For the same data acquisition time, the signal-to-noise for the rapid-scan absorption spectra was about an order of magnitude higher than for continuous wave first-derivative spectra recorded with modulation amplitudes that do not broaden the lineshapes. PMID:25240151

  15. (Environmental technology)

    SciTech Connect

    Boston, H.L.

    1990-10-12

    The traveler participated in a conference on environmental technology in Paris, sponsored by the US Embassy-Paris, US Environmental Protection Agency (EPA), the French Environmental Ministry, and others. The traveler sat on a panel for environmental aspects of energy technology and made a presentation on the potential contributions of Oak Ridge National Laboratory (ORNL) to a planned French-American Environmental Technologies Institute in Chattanooga, Tennessee, and Evry, France. This institute would provide opportunities for international cooperation on environmental issues and technology transfer related to environmental protection, monitoring, and restoration at US Department of Energy (DOE) facilities. The traveler also attended the Fourth International Conference on Environmental Contamination in Barcelona. Conference topics included environmental chemistry, land disposal of wastes, treatment of toxic wastes, micropollutants, trace organics, artificial radionuclides in the environment, and the use biomonitoring and biosystems for environmental assessment. The traveler presented a paper on The Fate of Radionuclides in Sewage Sludge Applied to Land.'' Those findings corresponded well with results from studies addressing the fate of fallout radionuclides from the Chernobyl nuclear accident. There was an exchange of new information on a number of topics of interest to DOE waste management and environmental restoration needs.

  16. A collection of Schottky-scan notes

    SciTech Connect

    Sabersky, A.P.

    1980-10-01

    This paper is a republication of ISR-RF notes and performance reports on work done in 1974-1975. The original notes have been edited, corrected and, in most cases, shortened. Discussed in this note are the following topics: noise, errors and the Schottky scan; speeding up the Schottky scan; Schottky markers and fast Schottky scans; and some engineering aspects of the fast Schottky scan.

  17. Scan speed control for tapping mode SPM

    PubMed Central

    2012-01-01

    In order to increase the imaging speed of a scanning probe microscope in tapping mode, we propose to use a dynamic controller on 'parachuting' regions. Furthermore, we propose to use variable scan speed on 'upward step' regions, with the speed determined by the error signal of the closed-loop control. We offer line traces obtained on a calibration grating with 25-nm step height, using both standard scanning and our scanning method, as experimental evidence. PMID:22333220

  18. Comparing laser printing and barcode scanning designs

    NASA Astrophysics Data System (ADS)

    MacArthur, Thomas D.

    1991-02-01

    A comparison of requirements and designs for barcode and non-impact printer scanners reveals similarities and differences that may be useful in leading to new solutions for barcode scanner problems. The non-impact printer scanner has been in volume production for over 10 years successfully achieving low cost high performance and high quality targets. Where requirements are found to overlap solutions already implemented and proven for printer applications may fmd further application in bar code scanners. Typical technologies used for printing include flying spot scanners liquid crystal shutters scophony scanners and LED arrays. Of primary concern in measuring figure of merit are such critical parameters as cost lifetime reliability conformance to regulatory standards environmental ruggedness power consumption compactness insensitivity to orientation acoustic noise produced modularity spot size depth of field exposure level and uniformity data rate scan length and uniformity and many more. A comparison of printing technologies their capabilities and their limitations with those used in barcode scanners may reveal common problems where we can take advantage of work already completed in similar application where requirements are found to overlap.

  19. Scanning tunneling microscopy of sulfide surfaces

    SciTech Connect

    Eggleston, C.M.; Hochella, M.F. Jr. )

    1990-05-01

    A fundamental understanding of reactions that occur at mineral surfaces, many of which have bearing on important environmental issues, requires knowledge of atomic surface structures. Scanning tunneling microscopy (STM) is a new technique which can be used to image atomic surface structures in real space. We briefly review STM theory and interpret STM images of galena (PbS) and pyrite (FeS{sub 2}) surfaces by comparing the bias-voltage dependence of the images to the electronic structures of the materials. This approach amounts to a form of tunneling spectroscopy which may ultimately be used to identify individual atoms on mineral surfaces. STM imaging was accomplished on fresh fracture surfaces as well as on surfaces that had been exposed to air for long periods of time. For galena, the Pb and S sites are distinguishable, and the S sites appear to be imaged preferentially. A galena surface which had been oxidized in air for several months was imaged, suggesting either that oxidation products are very thin, occur in local patches on the surface, or are both non-conductive and not coherently bound to the galena surface. Iron appears to be imaged preferentially on fresh fracture surfaces of pyrite. Atomic positions on a pyrite growth surface were not those expected for a termination of the bulk pyrite structure; it is likely that a surface oxidation product was imaged.

  20. Suspension system for gimbal supported scanning payloads

    NASA Technical Reports Server (NTRS)

    Polites, Michael E. (Inventor)

    1995-01-01

    Gimballed scanning devices or instruments are the subject of this invention. Scanning is an important aspect of space science. To achieve a scan pattern some means must be provided which impart to the payload an oscillatory motion. Various forms of machines have been employed for controllably conferring on scanning instruments predetermined scan patterns. They include control moment gyroscopes, reaction wheels, torque motors, reaction control systems, and the like. But rotating unbalanced mass (RUM) devices are a new and efficient way to generate scans in gimballed payloads. RUM devices are superior to previous scanning apparatus, but they require power consuming and frequently complex auxiliary control systems to position and reposition the particular scan pattern relative to a target or a number of targets. Herein the control system is simplified. The most frequently employed method for achieving the various scan patterns is to gimbal the scanning device. Gimbals are suspended in such a way that they can be activated to generate the scan pattern. The suspension means described is for payloads supported in gimbals wherein the payload rotation is restricted by a flex pivot so that the payload oscillates, thereby moving in a scan pattern.

  1. Immobilization of DNA for scanning probe microscopy.

    PubMed Central

    Allison, D P; Bottomley, L A; Thundat, T; Brown, G M; Woychik, R P; Schrick, J J; Jacobson, K B; Warmack, R J

    1992-01-01

    Reproducible scanning tunneling microscope and atomic force microscope images of entire molecules of uncoated plasmid DNA chemically bound to surfaces are presented. The chemically mediated immobilization of DNA to surfaces and subsequent scanning tunneling microscope imaging of DNA molecules demonstrate that the problem of molecular instability to forces exerted by the probe tip, inherent with scanning probe microscopes, can be prevented. Images PMID:1438201

  2. Suspension system for gimbal supported scanning payloads

    NASA Astrophysics Data System (ADS)

    Polites, Michael E.

    1995-03-01

    Gimballed scanning devices or instruments are the subject of this invention. Scanning is an important aspect of space science. To achieve a scan pattern some means must be provided which impart to the payload an oscillatory motion. Various forms of machines have been employed for controllably conferring on scanning instruments predetermined scan patterns. They include control moment gyroscopes, reaction wheels, torque motors, reaction control systems, and the like. But rotating unbalanced mass (RUM) devices are a new and efficient way to generate scans in gimballed payloads. RUM devices are superior to previous scanning apparatus, but they require power consuming and frequently complex auxiliary control systems to position and reposition the particular scan pattern relative to a target or a number of targets. Herein the control system is simplified. The most frequently employed method for achieving the various scan patterns is to gimbal the scanning device. Gimbals are suspended in such a way that they can be activated to generate the scan pattern. The suspension means described is for payloads supported in gimbals wherein the payload rotation is restricted by a flex pivot so that the payload oscillates, thereby moving in a scan pattern.

  3. Mouse manipulation through single-switch scanning.

    PubMed

    Blackstien-Adler, Susie; Shein, Fraser; Quintal, Janet; Birch, Shae; Weiss, Patrice L Tamar

    2004-01-01

    Given the current extensive reliance on the graphical user interface, independent access to computer software requires that users be able to manipulate a pointing device of some type (e.g., mouse, trackball) or be able to emulate a mouse by some other means (e.g., scanning). The purpose of the present study was to identify one or more optimal single-switch scanning mouse emulation strategies. Four alternative scanning strategies (continuous Cartesian, discrete Cartesian, rotational, and hybrid quadrant/continuous Cartesian) were selected for testing based on current market availability as well as on theoretical considerations of their potential speed and accuracy. Each strategy was evaluated using a repeated measures study design by means of a test program that permitted mouse emulation via any one of four scanning strategies in a motivating environment; response speed and accuracy could be automatically recorded and considered in view of the motor, cognitive, and perceptual demands of each scanning strategy. Ten individuals whose disabilities required them to operate a computer via single-switch scanning participated in the study. Results indicated that Cartesian scanning was the preferred and most effective scanning strategy. There were no significant differences between results from the Continuous Cartesian and Discrete Cartesian scanning strategies. Rotational scanning was quite slow with respect to the other strategies, although it was equally accurate. Hybrid Quadrant scanning improved access time but at the cost of fewer correct selections. These results demonstrated the importance of testing and comparing alternate single-switch scanning strategies.

  4. Optical scanning tests of complex CMOS microcircuits

    NASA Technical Reports Server (NTRS)

    Levy, M. E.; Erickson, J. J.

    1977-01-01

    The new test method was based on the use of a raster-scanned optical stimulus in combination with special electrical test procedures. The raster-scanned optical stimulus was provided by an optical spot scanner, an instrument that combines a scanning optical microscope with electronic instrumentation to process and display the electric photoresponse signal induced in a device that is being tested.

  5. Optimizing Lidar Scanning Strategies for Wind Energy Measurements (Invited)

    NASA Astrophysics Data System (ADS)

    Newman, J. F.; Bonin, T. A.; Klein, P.; Wharton, S.; Chilson, P. B.

    2013-12-01

    Environmental concerns and rising fossil fuel prices have prompted rapid development in the renewable energy sector. Wind energy, in particular, has become increasingly popular in the United States. However, the intermittency of available wind energy makes it difficult to integrate wind energy into the power grid. Thus, the expansion and successful implementation of wind energy requires accurate wind resource assessments and wind power forecasts. The actual power produced by a turbine is affected by the wind speeds and turbulence levels experienced across the turbine rotor disk. Because of the range of measurement heights required for wind power estimation, remote sensing devices (e.g., lidar) are ideally suited for these purposes. However, the volume averaging inherent in remote sensing technology produces turbulence estimates that are different from those estimated by a sonic anemometer mounted on a standard meteorological tower. In addition, most lidars intended for wind energy purposes utilize a standard Doppler beam-swinging or Velocity-Azimuth Display technique to estimate the three-dimensional wind vector. These scanning strategies are ideal for measuring mean wind speeds but are likely inadequate for measuring turbulence. In order to examine the impact of different lidar scanning strategies on turbulence measurements, a WindCube lidar, a scanning Halo lidar, and a scanning Galion lidar were deployed at the Southern Great Plains Atmospheric Radiation Measurement (ARM) site in Summer 2013. Existing instrumentation at the ARM site, including a 60-m meteorological tower and an additional scanning Halo lidar, were used in conjunction with the deployed lidars to evaluate several user-defined scanning strategies. For part of the experiment, all three scanning lidars were pointed at approximately the same point in space and a tri-Doppler analysis was completed to calculate the three-dimensional wind vector every 1 second. In another part of the experiment, one of

  6. Scanning laser polarimetry in glaucoma

    PubMed Central

    Dada, Tanuj; Sharma, Reetika; Angmo, Dewang; Sinha, Gautam; Bhartiya, Shibal; Mishra, Sanjay K; Panda, Anita; Sihota, Ramanjit

    2014-01-01

    Glaucoma is an acquired progressive optic neuropathy which is characterized by changes in the optic nerve head and retinal nerve fiber layer (RNFL). White-on-white perimetry is the gold standard for the diagnosis of glaucoma. However, it can detect defects in the visual field only after the loss of as many as 40% of the ganglion cells. Hence, the measurement of RNFL thickness has come up. Optical coherence tomography and scanning laser polarimetry (SLP) are the techniques that utilize the evaluation of RNFL for the evaluation of glaucoma. SLP provides RNFL thickness measurements based upon the birefringence of the retinal ganglion cell axons. We have reviewed the published literature on the use of SLP in glaucoma. This review elucidates the technological principles, recent developments and the role of SLP in the diagnosis and monitoring of glaucomatous optic neuropathy, in the light of scientific evidence so far. PMID:25494244

  7. Scanning laser polarimetry in glaucoma.

    PubMed

    Dada, Tanuj; Sharma, Reetika; Angmo, Dewang; Sinha, Gautam; Bhartiya, Shibal; Mishra, Sanjay K; Panda, Anita; Sihota, Ramanjit

    2014-11-01

    Glaucoma is an acquired progressive optic neuropathy which is characterized by changes in the optic nerve head and retinal nerve fiber layer (RNFL). White-on-white perimetry is the gold standard for the diagnosis of glaucoma. However, it can detect defects in the visual field only after the loss of as many as 40% of the ganglion cells. Hence, the measurement of RNFL thickness has come up. Optical coherence tomography and scanning laser polarimetry (SLP) are the techniques that utilize the evaluation of RNFL for the evaluation of glaucoma. SLP provides RNFL thickness measurements based upon the birefringence of the retinal ganglion cell axons. We have reviewed the published literature on the use of SLP in glaucoma. This review elucidates the technological principles, recent developments and the role of SLP in the diagnosis and monitoring of glaucomatous optic neuropathy, in the light of scientific evidence so far.

  8. Scanning Electrochemical Microscopy in Neuroscience

    NASA Astrophysics Data System (ADS)

    Schulte, Albert; Nebel, Michaela; Schuhmann, Wolfgang

    2010-07-01

    This article reviews recent work involving the application of scanning electrochemical microscopy (SECM) to the study of individual cultured living cells, with an emphasis on topographical and functional imaging of neuronal and secretory cells of the nervous and endocrine system. The basic principles of biological SECM and associated negative amperometric-feedback and generator/collector-mode SECM imaging are discussed, and successful use of the methodology for screening soft and fragile membranous objects is outlined. The drawbacks of the constant-height mode of probe movement and the benefits of the constant-distance mode of SECM operation are described. Finally, representative examples of constant-height and constant-distance mode SECM on a variety of live cells are highlighted to demonstrate the current status of single-cell SECM in general and of SECM in neuroscience in particular.

  9. Scanning ARM Cloud Radar Handbook

    SciTech Connect

    Widener, K; Bharadwaj, N; Johnson, K

    2012-06-18

    The scanning ARM cloud radar (SACR) is a polarimetric Doppler radar consisting of three different radar designs based on operating frequency. These are designated as follows: (1) X-band SACR (X-SACR); (2) Ka-band SACR (Ka-SACR); and (3) W-band SACR (W-SACR). There are two SACRs on a single pedestal at each site where SACRs are deployed. The selection of the operating frequencies at each deployed site is predominantly determined by atmospheric attenuation at the site. Because RF attenuation increases with atmospheric water vapor content, ARM's Tropical Western Pacific (TWP) sites use the X-/Ka-band frequency pair. The Southern Great Plains (SGP) and North Slope of Alaska (NSA) sites field the Ka-/W-band frequency pair. One ARM Mobile Facility (AMF1) has a Ka/W-SACR and the other (AMF2) has a X/Ka-SACR.

  10. UAVSAR Active Electronically Scanned Array

    NASA Technical Reports Server (NTRS)

    Sadowy, Gregory, A.; Chamberlain, Neil F.; Zawadzki, Mark S.; Brown, Kyle M.; Fisher, Charles D.; Figueroa, Harry S.; Hamilton, Gary A.; Jones, Cathleen E.; Vorperian, Vatche; Grando, Maurio B.

    2011-01-01

    The Uninhabited Airborne Vehicle Synthetic Aperture Radar (UAVSAR) is a pod-based, L-band (1.26 GHz), repeatpass, interferometric, synthetic aperture radar (InSAR) used for Earth science applications. Repeat-pass interferometric radar measurements from an airborne platform require an antenna that can be steered to maintain the same angle with respect to the flight track over a wide range of aircraft yaw angles. In order to be able to collect repeat-pass InSAR data over a wide range of wind conditions, UAVSAR employs an active electronically scanned array (AESA). During data collection, the UAVSAR flight software continuously reads the aircraft attitude state measured by the Embedded GPS/INS system (EGI) and electronically steers the beam so that it remains perpendicular to the flight track throughout the data collection

  11. New Research by CCD Scanning for Comets and Asteroids

    NASA Technical Reports Server (NTRS)

    Gehrels, Tom

    1997-01-01

    Spacewatch was begun in 1980; its purpose is to explore the various populations of small objects within the solar system. Spacewatch provides data for studies of comets and asteroids, finds potential targets for space missions, and provides information on the environmental problem of possible impacts. Moving objects are discovered by scanning the sky with charge-coupled devices (CCDS) on the 0.9-meter Spacewatch Telescope of the University of Arizona on Kitt Peak. Each Spacewatch scan consists of three drift scan passes over an area of sky using a CCD filtered to a bandpass of 0.5-1.0 pm (approximately V+R+I with peak sensitivity at 0.7 pm). The effective exposure time for each pass is 143 seconds multiplied by the secant of the declination. The area covered by each scan is 32 arcminutes in declination by about 28 minutes of time in right ascension. The image scale is 1.05 arcseconds per pixel. Three passes take about 1.5 hours to complete and show motions of individual objects over a one hour time baseline. The limiting magnitude is about 21.5 in single scans. CCD scanning was developed by Spacewatch in the early 1980s, with improvements still being made - particularly by bringing a new 1.8-m Spacewatch Telescope on line. In the meantime, we have been finding some 30,000 new asteroids per year and applying their statistics to the study of the collisional history of the solar system. Spacewatch had found a total of 150 Near-Earth Asteroids (NEAS) and 8 new comets, and had recovered one lost comet (P/Spitaler in 1993). Spacewatch is also efficient in recovery of known comets and has detected and reported positions for more than 137,000 asteroids, mostly new ones in the main belt, including more than 10,882 asteroids designated by the Minor Planet Center (MPC).

  12. Fast scanning mode and its realization in a scanning acoustic microscope

    SciTech Connect

    Ju Bingfeng; Bai Xiaolong; Chen Jian

    2012-03-15

    The scanning speed of the two-dimensional stage dominates the efficiency of mechanical scanning measurement systems. This paper focused on a detailed scanning time analysis of conventional raster and spiral scan modes and then proposed two fast alternative scanning modes. Performed on a self-developed scanning acoustic microscope (SAM), the measured images obtained by using the conventional scan mode and fast scan modes are compared. The total scanning time is reduced by 29% of the two proposed fast scan modes. It will offer a better solution for high speed scanning without sacrificing the system stability, and will not introduce additional difficulties to the configuration of scanning measurement systems. They can be easily applied to the mechanical scanning measuring systems with different driving actuators such as piezoelectric, linear motor, dc motor, and so on. The proposed fast raster and square spiral scan modes are realized in SAM, but not specially designed for it. Therefore, they have universal adaptability and can be applied to other scanning measurement systems with two-dimensional mechanical scanning stages, such as atomic force microscope or scanning tunneling microscope.

  13. Fast scanning mode and its realization in a scanning acoustic microscope.

    PubMed

    Ju, Bing-Feng; Bai, Xiaolong; Chen, Jian

    2012-03-01

    The scanning speed of the two-dimensional stage dominates the efficiency of mechanical scanning measurement systems. This paper focused on a detailed scanning time analysis of conventional raster and spiral scan modes and then proposed two fast alternative scanning modes. Performed on a self-developed scanning acoustic microscope (SAM), the measured images obtained by using the conventional scan mode and fast scan modes are compared. The total scanning time is reduced by 29% of the two proposed fast scan modes. It will offer a better solution for high speed scanning without sacrificing the system stability, and will not introduce additional difficulties to the configuration of scanning measurement systems. They can be easily applied to the mechanical scanning measuring systems with different driving actuators such as piezoelectric, linear motor, dc motor, and so on. The proposed fast raster and square spiral scan modes are realized in SAM, but not specially designed for it. Therefore, they have universal adaptability and can be applied to other scanning measurement systems with two-dimensional mechanical scanning stages, such as atomic force microscope or scanning tunneling microscope.

  14. Simultaneously scanning two connected tips in a scanning tunneling microscope

    NASA Astrophysics Data System (ADS)

    Liao, Wan-Ting; Lobb, C. J.; Wellstood, F. C.; Dreyer, M.

    2017-06-01

    We have modified a dual-tip scanning tunneling microscope (STM) by electrically connecting the tips together with a short (3 mm) strip of flexible 25 μm thick Nb foil. For simultaneous topographic imaging with both tips, we moved each tip to within tunneling distance z of a surface and modulated one tip's z-piezo at 5 kHz and the other at 10 kHz. The resulting combined tunneling current has modulation at both frequencies which we detect using individual lock-in amplifiers. Each lock-in output is fed back to its corresponding tip's individual STM z-position controller to maintain a stable current in both junctions. During the tests at room temperature, simultaneous imaging was performed with both tips made of Pt-Ir on Au/mica and highly oriented pyrolytic graphite (HOPG) samples, where a small tip-to-tip mechanical coupling was observed. We describe the system's performance, show results from simultaneous imaging, and discuss the potential application of the system to imaging superconducting phase differences.

  15. Scanning Tunneling Optical Resonance Microscopy

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Wilt, Dave; Raffaelle, Ryne; Gennett, Tom; Tin, Padetha; Lau, Janice; Castro, Stephanie; Jenkins, Philip; Scheiman, Dave

    2003-01-01

    Scanning tunneling optical resonance microscopy (STORM) is a method, now undergoing development, for measuring optoelectronic properties of materials and devices on the nanoscale by means of a combination of (1) traditional scanning tunneling microscopy (STM) with (2) tunable laser spectroscopy. In STORM, an STM tip probing a semiconductor is illuminated with modulated light at a wavelength in the visible-to-near-infrared range and the resulting photoenhancement of the tunneling current is measured as a function of the illuminating wavelength. The photoenhancement of tunneling current occurs when the laser photon energy is sufficient to excite charge carriers into the conduction band of the semiconductor. Figure 1 schematically depicts a proposed STORM apparatus. The light for illuminating the semiconductor specimen at the STM would be generated by a ring laser that would be tunable across the wavelength range of interest. The laser beam would be chopped by an achromatic liquid-crystal modulator. A polarization-maintaining optical fiber would couple the light to the tip/sample junction of a commercial STM. An STM can be operated in one of two modes: constant height or constant current. A STORM apparatus would be operated in the constant-current mode, in which the height of the tip relative to the specimen would be varied in order to keep the tunneling current constant. In this mode, a feedback control circuit adjusts the voltage applied to a piezoelectric actuator in the STM that adjusts the height of the STM tip to keep the tunneling current constant. The exponential relationship between the tunneling current and tip-to-sample distance makes it relatively easy to implement this mode of operation. The choice of method by which the photoenhanced portion of the tunneling current would be measured depends on choice of the frequency at which the input illumination would be modulated (chopped). If the frequency of modulation were low enough (typically < 10 Hz) that the

  16. Advanced oxidation scanning probe lithography.

    PubMed

    Ryu, Yu K; Garcia, Ricardo

    2017-04-07

    Force microscopy enables a variety of approaches to manipulate and/or modify surfaces. Few of those methods have evolved into advanced probe-based lithographies. Oxidation scanning probe lithography (o-SPL) is the only lithography that enables the direct and resist-less nanoscale patterning of a large variety of materials, from metals to semiconductors; from self-assembled monolayers to biomolecules. Oxidation SPL has also been applied to develop sophisticated electronic and nanomechanical devices such as quantum dots, quantum point contacts, nanowire transistors or mechanical resonators. Here, we review the principles, instrumentation aspects and some device applications of o-SPL. Our focus is to provide a balanced view of the method that introduces the key steps in its evolution, provides some detailed explanations on its fundamentals and presents current trends and applications. To illustrate the capabilities and potential of o-SPL as an alternative lithography we have favored the most recent and updated contributions in nanopatterning and device fabrication.

  17. Scanning probe block copolymer lithography

    PubMed Central

    Chai, Jinan; Huo, Fengwei; Zheng, Zijian; Giam, Louise R.; Shim, Wooyoung; Mirkin, Chad A.

    2010-01-01

    Integration of individual nanoparticles into desired spatial arrangements over large areas is a prerequisite for exploiting their unique electrical, optical, and chemical properties. However, positioning single sub-10-nm nanoparticles in a specific location individually on a substrate remains challenging. Herein we have developed a unique approach, termed scanning probe block copolymer lithography, which enables one to control the growth and position of individual nanoparticles in situ. This technique relies on either dip-pen nanolithography (DPN) or polymer pen lithography (PPL) to transfer phase-separating block copolymer inks in the form of 100 or more nanometer features on an underlying substrate. Reduction of the metal ions via plasma results in the high-yield formation of single crystal nanoparticles per block copolymer feature. Because the size of each feature controls the number of metal atoms within it, the DPN or PPL step can be used to control precisely the size of each nanocrystal down to 4.8 ± 0.2 nm. PMID:21059942

  18. Advanced oxidation scanning probe lithography

    NASA Astrophysics Data System (ADS)

    Ryu, Yu K.; Garcia, Ricardo

    2017-04-01

    Force microscopy enables a variety of approaches to manipulate and/or modify surfaces. Few of those methods have evolved into advanced probe-based lithographies. Oxidation scanning probe lithography (o-SPL) is the only lithography that enables the direct and resist-less nanoscale patterning of a large variety of materials, from metals to semiconductors; from self-assembled monolayers to biomolecules. Oxidation SPL has also been applied to develop sophisticated electronic and nanomechanical devices such as quantum dots, quantum point contacts, nanowire transistors or mechanical resonators. Here, we review the principles, instrumentation aspects and some device applications of o-SPL. Our focus is to provide a balanced view of the method that introduces the key steps in its evolution, provides some detailed explanations on its fundamentals and presents current trends and applications. To illustrate the capabilities and potential of o-SPL as an alternative lithography we have favored the most recent and updated contributions in nanopatterning and device fabrication.

  19. A New First-Scan Method for Two-Scan Labeling Algorithms

    NASA Astrophysics Data System (ADS)

    He, Lifeng; Chao, Yuyan; Suzuki, Kenji

    This paper proposes a new first-scan method for two-scan labeling algorithms. In the first scan, our proposed method first scans every fourth image line, and processes the scan line and its two neighbor lines. Then, it processes the remaining lines from top to bottom one by one. Our method decreases the average number of times that must be checked to process a foreground pixel will; thus, the efficiency of labeling can be improved.

  20. Excitation-scanning hyperspectral imaging microscope.

    PubMed

    Favreau, Peter F; Hernandez, Clarissa; Heaster, Tiffany; Alvarez, Diego F; Rich, Thomas C; Prabhat, Prashant; Leavesley, Silas J

    2014-04-01

    Hyperspectral imaging is a versatile tool that has recently been applied to a variety of biomedical applications, notably live-cell and whole-tissue signaling. Traditional hyperspectral imaging approaches filter the fluorescence emission over a broad wavelength range while exciting at a single band. However, these emission-scanning approaches have shown reduced sensitivity due to light attenuation from spectral filtering. Consequently, emission scanning has limited applicability for time-sensitive studies and photosensitive applications. In this work, we have developed an excitation-scanning hyperspectral imaging microscope that overcomes these limitations by providing high transmission with short acquisition times. This is achieved by filtering the fluorescence excitation rather than the emission. We tested the efficacy of the excitation-scanning microscope in a side-by-side comparison with emission scanning for detection of green fluorescent protein (GFP)-expressing endothelial cells in highly autofluorescent lung tissue. Excitation scanning provided higher signal-to-noise characteristics, as well as shorter acquisition times (300  ms/wavelength band with excitation scanning versus 3  s/wavelength band with emission scanning). Excitation scanning also provided higher delineation of nuclear and cell borders, and increased identification of GFP regions in highly autofluorescent tissue. These results demonstrate excitation scanning has utility in a wide range of time-dependent and photosensitive applications.

  1. Excitation-scanning hyperspectral imaging microscope

    PubMed Central

    Favreau, Peter F.; Hernandez, Clarissa; Heaster, Tiffany; Alvarez, Diego F.; Rich, Thomas C.; Prabhat, Prashant; Leavesley, Silas J.

    2014-01-01

    Abstract. Hyperspectral imaging is a versatile tool that has recently been applied to a variety of biomedical applications, notably live-cell and whole-tissue signaling. Traditional hyperspectral imaging approaches filter the fluorescence emission over a broad wavelength range while exciting at a single band. However, these emission-scanning approaches have shown reduced sensitivity due to light attenuation from spectral filtering. Consequently, emission scanning has limited applicability for time-sensitive studies and photosensitive applications. In this work, we have developed an excitation-scanning hyperspectral imaging microscope that overcomes these limitations by providing high transmission with short acquisition times. This is achieved by filtering the fluorescence excitation rather than the emission. We tested the efficacy of the excitation-scanning microscope in a side-by-side comparison with emission scanning for detection of green fluorescent protein (GFP)-expressing endothelial cells in highly autofluorescent lung tissue. Excitation scanning provided higher signal-to-noise characteristics, as well as shorter acquisition times (300  ms/wavelength band with excitation scanning versus 3  s/wavelength band with emission scanning). Excitation scanning also provided higher delineation of nuclear and cell borders, and increased identification of GFP regions in highly autofluorescent tissue. These results demonstrate excitation scanning has utility in a wide range of time-dependent and photosensitive applications. PMID:24727909

  2. Environmental occurrences

    SciTech Connect

    Black, D.G.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the onsite and offsite releases of radioactive and regulated materials. The specific agencies notified of the releases depended on the type, amount, and location of the individual occurrences. The more significant of these off-normal environmental occurrences are summarized in this section.

  3. Environmental Cartoons.

    ERIC Educational Resources Information Center

    Rowell, Elizabeth H.; Goodkind, Thomas B.

    1989-01-01

    Analyzes editorial cartoons from 1972-87 to determine extent and type of attention to environmental issues. Explores cartoons' direct and indirect messages regarding outdoors. Describes cartoons about energy, environment, pollution, space. Discusses artists' use of animals, vegetation, and outdoor activities. Identifies environmental issues as…

  4. Environmental mastitis.

    PubMed

    Smith, K L; Hogan, J S

    1993-11-01

    Environmental mastitis affects all dairy farms and generally is the major mastitis problem on modern, well managed dairy farms. Control measures effective against contagious pathogens are of little value in controlling of environmental pathogens. Control of environmental mastitis is achieved by reducing exposure of teat ends to environmental pathogens and by maximizing the resistance of the cow to intramammary infection. Significant sources of environmental pathogens are organic bedding materials, manure covered alleyways, and wet or damp areas in barns, exercise lots, or pastures. Milking time hygiene can influence teat-end exposure. In general, exposure is minimized when all areas of the environment are clean, cool, and dry. Resistance is maximized by providing a stress-free environment that minimizes teat-end injury, and by feeding balanced diets sufficient in vitamin E and selenium. Antibiotic therapy during lactation or the dry period is of little value in the control of environmental mastitis in dairy herds, with the exception of preventing environmental streptococcal infection during the early dry period. Effective vaccines may help reduce the impact of environmental mastitis in the near future.

  5. Environmental Cartoons.

    ERIC Educational Resources Information Center

    Rowell, Elizabeth H.; Goodkind, Thomas B.

    1989-01-01

    Analyzes editorial cartoons from 1972-87 to determine extent and type of attention to environmental issues. Explores cartoons' direct and indirect messages regarding outdoors. Describes cartoons about energy, environment, pollution, space. Discusses artists' use of animals, vegetation, and outdoor activities. Identifies environmental issues as…

  6. Environmental Epigenetics

    PubMed Central

    Bollati, Valentina; Baccarelli, Andrea

    2011-01-01

    Purpose of the review Epigenetics investigates heritable changes in gene expression occurring without changes in DNA sequence. Several epigenetic mechanisms, including DNA methylation and histone modifications, can change genome function under exogenous influence. We review current evidence indicating that epigenetic alterations mediate effects from exposure to environmental toxicants. Recent findings Results from animal models indicate that in-utero or early-life environmental exposures produce effects that can be inherited transgenerationally and are accompanied by epigenetic alterations. The search for human equivalents of the epigenetic mechanisms identified in animal models is under way. Recent investigations have identified a number of environmental toxicants that cause altered methylation of human repetitive elements or genes. Some exposures can alter epigenetic states and the same and/or similar epigenetic alterations can be found in patients with the disease of concern. Based on current evidence, we propose possible models for the interplay between environmental exposures and the human epigenome. Summary Several investigations have examined the relation between exposure to environmental chemicals and epigenetics, and identified toxicants that modify epigenetic states. Whether environmental exposures have transgenerational epigenetic effects in humans remains to be elucidated. In spite of the current limitations, available evidence supports the concept that epigenetics holds substantial potential for furthering our understanding of the molecular mechanisms of environmental toxicants, as well as for predicting health-related risks due to conditions of environmental exposure and individual susceptibility. PMID:20179736

  7. ENVIRONMENTAL MANAGEMENT

    EPA Science Inventory

    This brochure is part of a series of information packages prepared by the United States Environmental Protection Agency (EPA). Aimed at the international community, the packages focus on key environmental and public health issues being investigated by EPA. The products highligh...

  8. ENVIRONMENTAL MANAGEMENT

    EPA Science Inventory

    This brochure is part of a series of information packages prepared by the United States Environmental Protection Agency (EPA). Aimed at the international community, the packages focus on key environmental and public health issues being investigated by EPA. The products highligh...

  9. Environmental assessment.

    PubMed

    Narayan, M C; Tennant, J

    1997-11-01

    The significance, standard elements, components, and documentation of an environmental assessment in home care are discussed. This assessment is delineated within Maslow's Hierarchy of Needs and from a functional perspective. An Environmental Assessment Form that can be used as a documentation tool is included.

  10. Environmental Health

    MedlinePlus

    ... Some environmental risks are a part of the natural world, like radon in the soil. Others are the result of human activities, like lead poisoning from paint, or exposure to asbestos or mercury from mining or industrial use. NIH: National Institute of Environmental Health Sciences

  11. Corporate environmentalism and environmental innovation.

    PubMed

    Chang, Ching-Hsing; Sam, Abdoul G

    2015-04-15

    Several papers have explored the effect of tighter environmental standards on environmental innovation. While mandatory regulation remains the central tenet of US environmental policy, the regulatory landscape has changed since the early 1990s with the increased recourse by federal and state agencies to corporate environmentalism--voluntary pollution prevention (P2) by firms--to achieve environmental improvements. We therefore estimate the effects of voluntary P2 activities on the patenting of environmental technologies by a sample of manufacturing firms. With our panel data of 352 firms over the 1991-2000 period, we adopt an instrumental variable Poisson framework to account for the count nature of patents and the endogeneity of the P2 adoption decision. Our results indicate that the adoption of voluntary P2 activities in the manufacturing sector has led to a statistically and economically significant increase in the number of environmental patents, suggesting that corporate environmentalism can act as a catalyst for investments in cleaner technologies. Our findings are internationally relevant given the increasing ubiquity of corporate environmentalism in both developed and developing economies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Correlation-steered scanning for scanning probe microscopes to overcome thermal drift for ultra-long time scanning.

    PubMed

    Zhang, Liansheng; Long, Qian; Liu, Yongbin; Zhang, Jie; Feng, Zhihua

    2016-07-01

    The thermal effect is one of the most important factors that influence the accuracy of nanoscale measurement and the surface topography of samples in scanning probe microscopes (SPMs). We propose a method called correlation-steered scanning, which is capable of overcoming three-dimensional thermal drifts in real time for ultra-long time scanned images. The image is scanned band by band with overlapping parts between adjacent bands. The vertical drift can be considered as linear and can thus be eliminated together with the tilt of the sample by applying the flattening method. Each band is artificially divided into several blocks for conveniently calculating lateral drifts on the basis of the overlapping area of adjacent bands through digital image correlation. The calculated lateral drifts are compensated to steer the scanning of the subsequent blocks, thus ensuring that all bands are parallel to one another. Experimental results proved that images scanned by the proposed method exhibited less distortions than those obtained from the traditional raster scanning method. The nanoscale measurement results based on the image obtained by the proposed method also showed high accuracy, with an error of less than 1.5%. By scanning as many bands as needed, the correlation-steered scanning method can obtain a highly precise SPM image of an ultra-large area.

  13. Correcting nonlinear drift distortion of scanning probe and scanning transmission electron microscopies from image pairs with orthogonal scan directions.

    PubMed

    Ophus, Colin; Ciston, Jim; Nelson, Chris T

    2016-03-01

    Unwanted motion of the probe with respect to the sample is a ubiquitous problem in scanning probe and scanning transmission electron microscopies, causing both linear and nonlinear artifacts in experimental images. We have designed a procedure to correct these artifacts by using orthogonal scan pairs to align each measurement line-by-line along the slow scan direction, by fitting contrast variation along the lines. We demonstrate the accuracy of our algorithm on both synthetic and experimental data and provide an implementation of our method. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Correcting nonlinear drift distortion of scanning probe and scanning transmission electron microscopies from image pairs with orthogonal scan directions

    DOE PAGES

    Ophus, Colin; Ciston, Jim; Nelson, Chris T.

    2015-12-10

    Unwanted motion of the probe with respect to the sample is a ubiquitous problem in scanning probe and scanning transmission electron microscopies, causing both linear and nonlinear artifacts in experimental images. We have designed a procedure to correct these artifacts by using orthogonal scan pairs to align each measurement line-by-line along the slow scan direction, by fitting contrast variation along the lines. We demonstrate the accuracy of our algorithm on both synthetic and experimental data and provide an implementation of our method.

  15. Environmental education.

    PubMed

    Lynch, D R; Hutchinson, C E

    1992-02-01

    The need for a new profession devoted to environmental matters is asserted. The qualities of such a profession are sketched, and it is argued that new initiatives in environmental education are needed in the form of graduate, professional programs with primary emphasis on practice. An example 2-year program is presented. A fundamental requirement is scientific competence; undergraduate preparation in the sciences or engineering is mandatory. The graduate curriculum itself is built on three primary cores: environmental science and engineering, business and management, and public policy. Additionally, an environmental round table is proposed as a focal point for academic, industrial, governmental, and public discussion on environmental matters. The round table would provide oversight for the professional educational program and an affiliated research institute.

  16. Environmental education.

    PubMed Central

    Lynch, D R; Hutchinson, C E

    1992-01-01

    The need for a new profession devoted to environmental matters is asserted. The qualities of such a profession are sketched, and it is argued that new initiatives in environmental education are needed in the form of graduate, professional programs with primary emphasis on practice. An example 2-year program is presented. A fundamental requirement is scientific competence; undergraduate preparation in the sciences or engineering is mandatory. The graduate curriculum itself is built on three primary cores: environmental science and engineering, business and management, and public policy. Additionally, an environmental round table is proposed as a focal point for academic, industrial, governmental, and public discussion on environmental matters. The round table would provide oversight for the professional educational program and an affiliated research institute. PMID:11607268

  17. Scanning Tunneling Microscopy analysis of space-exposed polymer films

    NASA Technical Reports Server (NTRS)

    Kalil, Carol R.; Young, Philip R.

    1993-01-01

    The characterization of the surface of selected space-exposed polymer films by Scanning Tunneling Microscopy (STM) is reported. Principles of STM, an emerging new technique for materials analysis, are reviewed. The analysis of several films which received up to 5.8 years of low Earth orbital (LEO) exposure onboard the NASA Long Duration Exposure Facility (LDEF) is discussed. Specimens included FEP Teflon thermal blanket material, Kapton film, and several experimental polymer films. Ultraviolet and atomic oxygen-induced crazing and erosion are described. The intent of this paper is to demonstrate how STM is enhancing the understanding of LEO space environmental effects on polymer films.

  18. Basis for optronic ScanSAR processing

    NASA Astrophysics Data System (ADS)

    Marchese, Linda; Bourqui, Pascal; Turgeon, Sandra; Harnish, Bernd; Suess, Martin; Châteauneuf, François; Bergeron, Alain

    2011-11-01

    ScanSAR is an important imaging mode of operation for SAR systems. It allows extended range coverage albeit at the expense of azimuth resolution. Compared to stripmap, ScanSAR is used more for large swath coverage for mapping and monitoring over a wide area. Applications are numerous and include boreal forest mapping, wetland mapping and soil moisture monitoring. The goal of the present work was thus to explore the possibility of processing ScanSAR data optronicaly. Tests were performed with artificially bursted ASAR stripmap data demonstrating that reconstruction of ScanSAR data using the optronic SAR processor is feasible. This paper describes specifically how the data control and handling of ScanSAR data is performed to make it compatible with the optronic processor that was otherwise specifically designed for stripmap processing. As well, the ScanSAR images generated optronicaly are presented.

  19. Image scanning microscopy with radially polarized light

    NASA Astrophysics Data System (ADS)

    Xiao, Yun; Zhang, Yunhai; Wei, Tongda; Huang, Wei; Shi, Yaqin

    2017-03-01

    In order to improve the resolution of image scanning microscopy, we present a method based on image scanning microscopy and radially polarized light. According to the theory of image scanning microscopy, we get the effective point spread function of image scanning microscopy with the longitudinal component of radially polarized light and a 1 AU detection area, and obtain imaging results of the analyzed samples using this method. Results show that the resolution can be enhanced by 7% compared with that in image scanning microscopy with circularly polarized light, and is 1.54-fold higher than that in confocal microscopy with a pinhole of 1 AU. Additionally, the peak intensity of ISM is 1.54-fold higher than that of a confocal microscopy with a pinhole of 1 AU. In conclusion, the combination of the image scanning microscopy and the radially polarized light could improve the resolution, and it could realize high-resolution and high SNR imaging at the same time.

  20. Background removal procedure for rapid scan EPR.

    PubMed

    Tseitlin, Mark; Czechowski, Tomasz; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2009-01-01

    In rapid scan EPR the changing magnetic field creates a background signal with components at the scan frequency and its harmonics. The amplitude of the background signal increases with scan width and is more significant for weak EPR signals such as are obtained in the presence of magnetic field gradients. A procedure for distinguishing this background from the EPR signal is proposed, mathematically described, and tested for various experimental conditions.

  1. CT densities in delayed iodine hepatic scanning

    SciTech Connect

    Perkerson, R.B. Jr.; Erwin, B.C.; Baumgartner, B.R.; Phillips, V.M.; Torres, W.E.; Clements, J.L. Jr.; Gedgaudas-McClees, K.; Bernardino, M.E.

    1985-05-01

    Sixty patients underwent CT scanning of the liver prior to, immediately after, and four hours after intravenous administration of 60% meglumine diatrizoate. Twenty patients received a 50 ml bolus of contrast material, 20 received 100 ml, and 20 received 200 ml. In each group, delayed CT scanning safely raised the inherent density of the liver significantly. Thus, delayed scanning with doses presently used in abdominal and neurological CT examinations may be helpful in detecting hepatic lesions.

  2. Scanning Tip Microscopy With Applications To Biology

    NASA Astrophysics Data System (ADS)

    Sarid, Dror; Thall, Edmond H.; Iams, Douglas A.; Ingle, Jeffery T.; Henson, Tammy D.; Lee, Y. C.; Bell, L. Stephen

    1989-06-01

    Scanning tunneling microscopy and atomic force microscopy, denoted here scanning tip microscopy, are two powerful novel techniques for imaging surfaces with atomic resolution. We describe the underlying principles of these two techniques with special emphasis on an instrument developed in our laboratory that uses a laser diode to detect minute deflections of a tip as it raster scans the surface of a sample. Applications of these techniques to research in biology are assessed and their relative merits discussed.

  3. Radiogallium scan in P. carinii pneumonia

    SciTech Connect

    Parthasarathy, K.L.; Bakshi, S.P.; Bender, M.A.

    1982-02-01

    A gallium scan performed on a patient with fever of unknown origin (FUO) revealed an abnormal uptake of radiotracer in the lungs despite negative chest roentgenographic examination and other routine diagnostic studies. Subsequent lung biopsy results confirmed the presence of Pneumocystis (P.) carinii infection. A repeat gallium scan obtained following appropriate antibiotic therapy was essentially normal. The importance of radiogallium scanning in an immunosuppressed patient with FUO is emphasized.

  4. Scanning Tunneling Microscopy Studies of Quasicrystals

    NASA Astrophysics Data System (ADS)

    Becker, Russell S.; Kortan, A. Refik

    The following sections are included: * INTRODUCTION * EXPERIMENTAL * X-RAY DIFFRACTION * SCANNING TUNNELING MICROSCOPY * STRUCTURE MODELLING BASED ON STM * COMPARISON WITH MODELS BASED ON BULK STUDIES * CONCLUSION * REFERENCES

  5. Scanning Tunneling Microscope For Use In Vacuum

    NASA Technical Reports Server (NTRS)

    Abel, Phillip B.

    1993-01-01

    Scanning tunneling microscope with subangstrom resolution developed to study surface structures. Although instrument used in air, designed especially for use in vacuum. Scanning head is assembly of small, mostly rigid components made of low-outgassing materials. Includes coarse-positioning mechanical-translation stage, on which specimen mounted by use of standard mounting stub. Tunneling tip mounted on piezoelectric fine-positioning tube. Application of suitable voltages to electrodes on piezoelectric tube controls scan of tunneling tip across surface of specimen. Electronic subsystem generates scanning voltages and collects data.

  6. Scanning Tunneling Microscope For Use In Vacuum

    NASA Technical Reports Server (NTRS)

    Abel, Phillip B.

    1993-01-01

    Scanning tunneling microscope with subangstrom resolution developed to study surface structures. Although instrument used in air, designed especially for use in vacuum. Scanning head is assembly of small, mostly rigid components made of low-outgassing materials. Includes coarse-positioning mechanical-translation stage, on which specimen mounted by use of standard mounting stub. Tunneling tip mounted on piezoelectric fine-positioning tube. Application of suitable voltages to electrodes on piezoelectric tube controls scan of tunneling tip across surface of specimen. Electronic subsystem generates scanning voltages and collects data.

  7. Scanned probe microscope for biological applications

    NASA Astrophysics Data System (ADS)

    Baiburin, Vil B.; Konnov, Nikolai P.; Shcherbakov, Anatolyi A.; Malakhaeva, Alina N.; Zadnova, Svetlana P.; Volkov, Yuri P.

    1997-12-01

    In our biophysical laboratory has been developed a new scanned probe microscope (SPM) for biological application. The SPM allows to investigate a biological samples' surface by means of three different near field microscopes: scanning tunneling microscope (STM), atomic force microscope (AFM) and near field scanning optical microscope (NSOM). The SPM is very rigid and can be operated in ordinary laboratory without any vibration isolation. The scanning area of the microscope is about 10 by 10 micrometers. Some different biological objects were visualized by means of the SPM viz. bacteria (E. Coli, plague, cholera, staphylococcus), macromolecules (DNA, plague proteins) and phage (T2).

  8. Scanning electron microscopy: preparation and imaging for SEM.

    PubMed

    Jones, Chris G

    2012-01-01

    Scanning electron microscopy (SEM) has been almost universally applied for the surface examination and characterization of both natural and man-made objects. Although an invasive technique, developments in electron microscopy over the years has given the microscopist a much clearer choice in how invasive the technique will be. With the advent of low vacuum SEM in the 1970s (The environmental cold stage, 1970) and environmental SEM in the late 1980s (J Microsc 160(pt. 1):9-19, 1989), it is now possible in some circumstances to examine samples without preparation. However, for the examination of biological tissue and cells it is still advisable to chemically fix, dehydrate, and coat samples for SEM imaging and analysis. This chapter aims to provide an overview of SEM as an imaging tool, and a general introduction to some of the methods applied for the preparation of samples.

  9. ENVIRONMENTAL IMMUNOCHEMISTRY

    EPA Science Inventory

    Environmental immunochemical methods are responding to the changing needs of regulatory and monitoring programs and are meeting new analytical challenges as they arise. Immunoassays are being developed for screening multiple organophosphorous (OP) pesticides (0,0-diethyl thionate...

  10. ENVIRONMENTAL HYDRAULICS

    EPA Science Inventory

    The thermal, chemical, and biological quality of water in rivers, lakes, reservoirs, and near coastal areas is inseparable from a consideration of hydraulic engineering principles: therefore, the term environmental hydraulics. In this chapter we discuss the basic principles of w...

  11. ENVIRONMENTAL IMMUNOCHEMISTRY

    EPA Science Inventory

    Environmental immunochemical methods are responding to the changing needs of regulatory and monitoring programs and are meeting new analytical challenges as they arise. Immunoassays are being developed for screening multiple organophosphorous (OP) pesticides (0,0-diethyl thionate...

  12. ENVIRONMENTAL HYDRAULICS

    EPA Science Inventory

    The thermal, chemical, and biological quality of water in rivers, lakes, reservoirs, and near coastal areas is inseparable from a consideration of hydraulic engineering principles: therefore, the term environmental hydraulics. In this chapter we discuss the basic principles of w...

  13. Environmental decontamination

    SciTech Connect

    Cristy, G.A.; Jernigan, H.C.

    1981-02-01

    The record of the proceedings of the workshop on environmental decontamination contains twenty-seven presentations. Emphasis is placed upon soil and surface decontamination, the decommissioning of nuclear facilities, and assessments of instrumentation and equipment used in decontamination. (DLS)

  14. Environmental pathology

    SciTech Connect

    Mottet, N.K.

    1985-01-01

    This book contains 14 selections. Some of the titles are: Injury by Ionizing Radiations; Urinary System; Immune System; Chemical Carcinogenesis; The Molecular Basis of Environmental Mutagenesis; and Reproductive Toxicity.

  15. ENVIRONMENTAL PHOTOBIOLOGY

    EPA Science Inventory

    Environmental aquatic photobiology is most commonly known for its links to global climate change. Ozone depletion is, however, not the only factor that alters the effects of ultraviolet radiation on biological systems. Alterations in water clarity, by acidification, reduced disso...

  16. Environmental era

    SciTech Connect

    Tucker, W.

    1982-02-01

    The emergence of environmentalism is a post 1960 phenomenon that has become increasingly conservative and elite in its effort to protect privilege rather than promote progress. Subgroups have successfully lobbied for regulations that force the public to pay for standards that benefit a small portion of the population. The environmentalist elite has benefited from our economic system, but sets high environmental goals to make it more difficult for others to benefit. Its positions conform to those of the aristocracy throughout history. Environmental elitists oppose putting a price on clean air regardless of any benefit to other social goals. The new elite grew out of an awareness that the middle class was enlarging and diluting prestige. After seeking early alliances with the socially disadvantaged, liberalism later turned to the traditional conservatism of the rich and upper middle class. The author traces this development and its parallel with an underlying wish for an environmental reckoning. (DCK)

  17. Environmental quality

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The potential use of space systems to help determine the current state of air, water, and land environments was examined; the effects of man's activities on these parameters were also examined. Data are limited to pollutants introduced into the major environmental media, environmental changes manifested by such pollutants, and the effectiveness of abatement and control methods. Data also cover land quality as related to land use and public health.

  18. Lung Perfusion Scanning in Hepatic Cirrhosis

    PubMed Central

    Stanley, N. N.; Ackrill, P.; Wood, J.

    1972-01-01

    Abnormal lung perfusion scans using radioactive particles were found in five out of six cases of hepatic cirrhosis with arterial hypoxaemia. None had clinical evidence of cardiopulmonary disease or signs of pulmonary embolism on arteriography. The scan defects are probably caused by a disorder of the pulmonary microvasculature, which may show regional variation in severity. ImagesFIG. 1FIG. 2 PMID:4645896

  19. Scanning System -- Technology Worth a Look

    Treesearch

    Philip A. Araman; Daniel L. Schmoldt; Richard W. Conners; D. Earl Kline

    1995-01-01

    In an effort to help automate the inspection for lumber defects, optical scanning systems are emerging as an alternative to the human eye. Although still in its infancy, scanning technology is being explored by machine companies and universities. This article was excerpted from "Machine Vision Systems for Grading and Processing Hardwood Lumber," by Philip...

  20. A Student-Built Scanning Tunneling Microscope

    ERIC Educational Resources Information Center

    Ekkens, Tom

    2015-01-01

    Many introductory and nanotechnology textbooks discuss the operation of various microscopes including atomic force (AFM), scanning tunneling (STM), and scanning electron microscopes (SEM). In a nanotechnology laboratory class, students frequently utilize microscopes to obtain data without a thought about the detailed operation of the tool itself.…

  1. Live ultrasound volume reconstruction using scout scanning

    NASA Astrophysics Data System (ADS)

    Meyer, Amelie; Lasso, Andras; Ungi, Tamas; Fichtinger, Gabor

    2015-03-01

    Ultrasound-guided interventions often necessitate scanning of deep-seated anatomical structures that may be hard to visualize. Visualization can be improved using reconstructed 3D ultrasound volumes. High-resolution 3D reconstruction of a large area during clinical interventions is challenging if the region of interest is unknown. We propose a two-stage scanning method allowing the user to perform quick low-resolution scouting followed by high-resolution live volume reconstruction. Scout scanning is accomplished by stacking 2D tracked ultrasound images into a low-resolution volume. Then, within a region of interest defined in the scout scan, live volume reconstruction can be performed by continuous scanning until sufficient image density is achieved. We implemented the workflow as a module of the open-source 3D Slicer application, within the SlicerIGT extension and building on the PLUS toolkit. Scout scanning is performed in a few seconds using 3 mm spacing to allow region of interest definition. Live reconstruction parameters are set to provide good image quality (0.5 mm spacing, hole filling enabled) and feedback is given during live scanning by regularly updated display of the reconstructed volume. Use of scout scanning may allow the physician to identify anatomical structures. Subsequent live volume reconstruction in a region of interest may assist in procedures such as targeting needle interventions or estimating brain shift during surgery.

  2. Implementing SCANS. Highlight Zone: Research @ Work.

    ERIC Educational Resources Information Center

    Packer, Arnold C.; Brainard, Scott

    Foremost among efforts over the last decade to improve the work-related skills required of all young people to meet the demands of American's workplaces was the Secretary's Commission on Achieving Necessary Skills Commission (SCANS). Integral to SCANS were its three-part foundation (basic skills, thinking skills, and personal qualities) and these…

  3. A Student-Built Scanning Tunneling Microscope

    ERIC Educational Resources Information Center

    Ekkens, Tom

    2015-01-01

    Many introductory and nanotechnology textbooks discuss the operation of various microscopes including atomic force (AFM), scanning tunneling (STM), and scanning electron microscopes (SEM). In a nanotechnology laboratory class, students frequently utilize microscopes to obtain data without a thought about the detailed operation of the tool itself.…

  4. Camera Systems Rapidly Scan Large Structures

    NASA Technical Reports Server (NTRS)

    2013-01-01

    Needing a method to quickly scan large structures like an aircraft wing, Langley Research Center developed the line scanning thermography (LST) system. LST works in tandem with a moving infrared camera to capture how a material responds to changes in temperature. Princeton Junction, New Jersey-based MISTRAS Group Inc. now licenses the technology and uses it in power stations and industrial plants.

  5. Ultrasonic scanning for pallet part grading

    Treesearch

    Mohammed F. Kabir; Daniel L. Schmoldt; Mark E. Schafer; Philip A. Araman

    2000-01-01

    Sorting and grading of wooden pallet parts are key factors for pallet manufacturing quality and pallet durability. The feasibility of ultrasonic scanning for defect detection in pallet manufacturing is examined in this report. Scanning was conducted by two pressure-contact rolling transducers in a pitch-catch arrangement. Pallet part deckboards were fed through the...

  6. The phase-scanned commutated array network

    NASA Astrophysics Data System (ADS)

    Young, R.

    An array feed network has been developed to demonstrate the P-Scan principle incorporating separate elevation and azimuth antennas. The microwave lens, switches, phase shifters, and amplitude control are discussed, and beam formation is described. The increased scan of the system is addressed, and the results of tests on the system are discussed.

  7. Optical Scanning for Retrospective Conversion of Information.

    ERIC Educational Resources Information Center

    Hein, Morten

    1986-01-01

    This discussion of the use of optical scanning and computer formatting for retrospective conversion focuses on a series of applications known as Optical Scanning for Creation of Information Databases (OSCID). Prior research in this area and the usefulness of OSCID for creating low-priced machine-readable data representing older materials are…

  8. Torque-while-turnaround scan mirror assembly

    NASA Technical Reports Server (NTRS)

    Starkus, C. J.

    1977-01-01

    A scan mirror assembly which is part of a thematic mapper system is described with emphasis on mechanical aspects of the design. Features of the oscillating scan mirror mechanism include: a low level of structural vibration for the impact energies involved in mirror oscillation and return of energy lost during impact to the mirror by applying torque during the instant of impact.

  9. Adjustable Deflector For Ultrasonic C-Scan

    NASA Technical Reports Server (NTRS)

    Chern, E. James

    1994-01-01

    Adjustable deflector increases versatility of ultrasonic C-scan system equipped with two-axis (x-y) translation stage. Enables system to scan along additional axis perpendicular (z axis) or tilted (z' axis) with respect to y axis. Modification of two-axis scanner is economical alternative to more-complicated scanner.

  10. The Scanning Process: Methods and Uses.

    ERIC Educational Resources Information Center

    Renfro, William L.; Morrison, James L.

    1983-01-01

    Developing a rational scanning process that reaches a balance between what is needed and what is possible within the limitations of an institution's resources is discussed. The different kinds of scanning, which kind to use at each stage of the process, and why are described. (MLW)

  11. The white blood cell scan in orthopedics

    SciTech Connect

    Propst-Proctor, S.L.; Dillingham, M.F.; McDougall, I.R.; Goodwin, D.

    1982-08-01

    A new nuclear scanning technique was found more specific for bone, joint, and soft tissue infections than any previously described scanning technique. The leukocyte scan, whereby a patient's own cells are labeled with a radioactive tagging agent (/sup 111/In oxine), can distinguish an active infectious process from other pain-inducing conditions. Ninety-seven /sup 111/In labeled autologous leukocyte scans were performed in 88 patients. The findings in 17 of 40 patients scanned for possible acute osteomyelitis, six of nine for suspected septic arthritis, and six for possible soft tissue infections, were positive. Subsequent clinical courses verified the infectious nature of these processes in all patients. Patients who had chronic osteomyelitis (14), bony metastases (four patients), heterotopic ossification (three), and degenerative arthritis (two) demonstrated negative findings. Of the seven patients scanned for acute long-bone fractures, one demonstrated positive findings. Nine scans demonstrated positive findings without determined causes. The leukocyte scan is a useful addition to the diagnostic tools of the orthopedic surgeon.

  12. Rotation of images by scan mirrors

    NASA Technical Reports Server (NTRS)

    Katzberg, Stephen J.

    1989-01-01

    An analysis is presented of the effects of scan mirrors on scene orientation or rotation for image forming systems. Some simple vector relationships are presented, which when combined with the anticipated application conditions, make it possible to easily assess image orientation effects resulting from scan mirrors. Examples are cited to demonstrate the application of the analysis.

  13. Getting a CAT Scan (For Kids)

    MedlinePlus Videos and Cool Tools

    ... dientes Video: Getting an X-ray Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  14. CERES Spatial Extent and Scan Modes

    Atmospheric Science Data Center

    2017-08-09

    ... the images show top of atmosphere all sky longwave measurements. CERES ERBE-like instantaneous ES-8 and monthly ... to a Programmable Azimuth Plane Scan (PAPS) to collect measurements over the  Chesapeake Lighthouse and Aircraft Measurements for Satellites (CLAMS)  site. The Special-Scan image is an ...

  15. Full cycle rapid scan EPR deconvolution algorithm

    NASA Astrophysics Data System (ADS)

    Tseytlin, Mark

    2017-08-01

    Rapid scan electron paramagnetic resonance (RS EPR) is a continuous-wave (CW) method that combines narrowband excitation and broadband detection. Sinusoidal magnetic field scans that span the entire EPR spectrum cause electron spin excitations twice during the scan period. Periodic transient RS signals are digitized and time-averaged. Deconvolution of absorption spectrum from the measured full-cycle signal is an ill-posed problem that does not have a stable solution because the magnetic field passes the same EPR line twice per sinusoidal scan during up- and down-field passages. As a result, RS signals consist of two contributions that need to be separated and postprocessed individually. Deconvolution of either of the contributions is a well-posed problem that has a stable solution. The current version of the RS EPR algorithm solves the separation problem by cutting the full-scan signal into two half-period pieces. This imposes a constraint on the experiment; the EPR signal must completely decay by the end of each half-scan in order to not be truncated. The constraint limits the maximum scan frequency and, therefore, the RS signal-to-noise gain. Faster scans permit the use of higher excitation powers without saturating the spin system, translating into a higher EPR sensitivity. A stable, full-scan algorithm is described in this paper that does not require truncation of the periodic response. This algorithm utilizes the additive property of linear systems: the response to a sum of two inputs is equal the sum of responses to each of the inputs separately. Based on this property, the mathematical model for CW RS EPR can be replaced by that of a sum of two independent full-cycle pulsed field-modulated experiments. In each of these experiments, the excitation power equals to zero during either up- or down-field scan. The full-cycle algorithm permits approaching the upper theoretical scan frequency limit; the transient spin system response must decay within the scan

  16. AVIRIS scan drive design and performance

    NASA Technical Reports Server (NTRS)

    Miller, D. C.

    1987-01-01

    The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) images the ground with an instantaneous field of view (IFOV) of 1 mrad. The IFOV is scanned 30 deg from left to right to provide the cross-track dimension of the image, while the aircraft's motion provides the along-track dimension. The scanning frequency is 12 Hz, with a scan efficiency of 70 percent. The scan mirror has an effective diameter of 5.7 in, and its positional accuracy is a small fraction of a milliradian of the nominal position-time profile. Described are the design and performance of the scan drive mechanism. Tradeoffs among various approaches are discussed, and the reasons given for the selection of the cam drive.

  17. Scanning tunneling microscope assembly, reactor, and system

    SciTech Connect

    Tao, Feng; Salmeron, Miquel; Somorjai, Gabor A

    2014-11-18

    An embodiment of a scanning tunneling microscope (STM) reactor includes a pressure vessel, an STM assembly, and three spring coupling objects. The pressure vessel includes a sealable port, an interior, and an exterior. An embodiment of an STM system includes a vacuum chamber, an STM reactor, and three springs. The three springs couple the STM reactor to the vacuum chamber and are operable to suspend the scanning tunneling microscope reactor within the interior of the vacuum chamber during operation of the STM reactor. An embodiment of an STM assembly includes a coarse displacement arrangement, a piezoelectric fine displacement scanning tube coupled to the coarse displacement arrangement, and a receiver. The piezoelectric fine displacement scanning tube is coupled to the coarse displacement arrangement. The receiver is coupled to the piezoelectric scanning tube and is operable to receive a tip holder, and the tip holder is operable to receive a tip.

  18. Optical scanning holography for stereoscopic display

    NASA Astrophysics Data System (ADS)

    Liu, Jung-Ping; Wen, Hsuan-Hsuan

    2016-10-01

    Optical Scanning Holography (OSH) is a scanning-type digital holographic recording technique. One of OSH's most important properties is that the OSH can record an incoherent hologram, which is free of speckle and thus is suitable for the applications of holographic display. The recording time of a scanning hologram is proportional to the sampling resolution. Hence the viewing angle as well as the resolution of a scanning hologram is limited for avoid too long recording. As a result, the viewing angle is not large enough for optical display. To solve this problem, we recorded two scanning holograms at different viewing angles. The two holograms are synthesized to a single stereoscopic hologram with two main viewing angles. In displaying, two views at the two main viewing angles are reconstructed. Because both views contain full-depth-resolved 3D scenes, the problem of accommodation conflict in conventional stereogram is avoided.

  19. Bone scan in metabolic bone diseases. Review.

    PubMed

    Abdelrazek, Saeid; Szumowski, Piotr; Rogowski, Franciszek; Kociura-Sawicka, Agnieszka; Mojsak, Małgorzata; Szorc, Małgorzata

    2012-08-25

    Metabolic bone disease encompasses a number of disorders that tend to present a generalized involvement of the whole skeleton. The disorders are mostly related to increased bone turnover and increased uptake of radiolabelled diphosphonate. Skeletal uptake of 99mTc-labelled diphosphonate depends primarily upon osteoblastic activity, and to a lesser extent, skeletal vascularity. A bone scan image therefore presents a functional display of total skeletal metabolism and has valuable role to play in the assessment of patients with metabolic bone disorders. However, the bone scan appearances in metabolic bone disease are often non-specific, and their recognition depends on increased tracer uptake throughout the whole skeleton. It is the presence of local lesions, as in metastatic disease, that makes a bone scan appearance obviously abnormal. In the early stages, there will be difficulty in evaluating the bone scans from many patients with metabolic bone disease. However, in the more severe cases scan appearances can be quite striking and virtually diagnostic.

  20. Means for Positioning and Repositioning Scanning Instruments

    NASA Technical Reports Server (NTRS)

    Polites, Michael E. (Inventor); Alhorn, Dean C. (Inventor)

    1996-01-01

    A method is presented for positioning a scanning instrument to point toward the center of the desired scan wherein the scan is achieved by rotating unbalanced masses (RUMs) rotating about fixed axes of rotation relative to and associated with the instrument, the RUMs being supported on drive shafts spaced from the center of the mass of the instrument and rotating 180 degrees out-of-phase with each other and in planes parallel to each other to achieve the scan. The elevation and cross-elevation angles of the instrument are sensed to determine any offset and offset time rate-of-change, and the magnitude and direction are converted to a RUM cycle angular velocity component to be superimposed on the nominal velocity of the RUMs. This RUM angular velocity component modulates the RUM angular velocity to cause the speed of the RUMs to increase and decrease during each revolution to drive the instrument toward the desired center of the scan.

  1. An Introduction to PunchScan

    NASA Astrophysics Data System (ADS)

    Popoveniuc, Stefan; Hosp, Ben

    PunchScan is a precinct-read optical-scan balloting system that allows voters to take their ballot with them after scanning. This does not violate the secret ballot principle because the ballots cannot be read without secret information held by the distributed authority in charge of the election. In fact, this election authority will publish the ballots for everyone to see, allowing voters whose ballots were incorrectly omitted to complain. PunchScan vote-counting is performed in private by the election authority - who uses their secret information to decode the ballots - but is verified in public by an auditor.In this paper we describe how and why PunchScan works. We have kept most of the description at an outline level so that it may be used as a straw model of a cryptographic voting system.

  2. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  3. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  4. Environmental teratogens.

    PubMed Central

    Brent, R. L.; Beckman, D. A.

    1990-01-01

    By far the largest category of malformations, 65% falls into the group of those with an unknown cause(s). Purely genetic causes of malformations (autosomal and cytogenetic), estimated to produce 20 to 25% of all human malformations, comprise the largest group of congenital malformations with known etiology. Although environmental causes of human malformations account for 10% or fewer of malformations, most of these environmentally induced malformations are related to maternal disease states. Fewer than 1% of all human malformations are related to drug exposure, chemicals, or radiation, but studies of environmentally induced malformations are important because they may teach us how to predict and test for teratogenicity, understand the mechanisms of teratogenesis from all etiologies, and provide a means by which human malformations can be prevented. PMID:2194610

  5. Compact scanning lidar systems using holographic optics

    NASA Astrophysics Data System (ADS)

    Schwemmer, Geary K.; Wilkerson, Thomas D.; Guerra, David

    1998-08-01

    Two scanning lidar systems have been built using holographic optical elements (HOE) that function as a scanning telescope primary optic. One is a ground based lidar using a reflection HOE, and uses a frequency doubled Nd:YAG laser transmitter. The other system is an airborne/ground based system that uses a transmission HOE and operates at the 1064 nm fundamental of the Nd:YAG laser. Each HOE has a focal spot on the center- line, normal to the flat disk holding the hologram, and a field of view (FOV) that points approximately 45 degrees from the normal. Rotating the disk effects a conical scan of the FOV. In both systems, the same HOE is also used to collimate and steer the transmitted laser beam. The utility of using the HOEs to save weight and size in scanning lidars is evidenced by the atmospheric backscatter data collected with these systems. They also will lower the cost of commercial systems due to the low cost of replicating HOEs and the simplified mechanical scanning systems. Development of airborne scanning lidar altimeters and other lidars and passive instruments using holographic optics are underway, including the development of a one meter diameter, space qualified holographic scanning telescope for use in the ultraviolet.

  6. The bone scan in inflammatory osseous disease.

    PubMed

    Handmaker, H; Leonards, R

    1976-01-01

    The 99mTc-phosphate bone scan has become a sensitive, reliable, and safe method for evaluating the patient with suspected inflammatory disease of bone. The scan may become positive as early as the first 24 hr after the symptoms and 10-14 days before roentgenographic changes occur. It can be used to differentiate successfully a variety of diseases from osteomyelitis, and in conjunction with 67Ga-citrate scan has become a mainstay in the work-up of the patient with infectious disease. Applications of the bone scan to infectious diseases in pediatric practice are especially helpful, since these diseases are common problems in this age group. Increased experience with the 99mTc-phosphate bone scan has already defined several areas of "limitations" in evaluating inflammatory disease. "Cold" defects, negative scans in early stages of osteomyelitis, and "extended uptake" may all pose problems in interpretation, but careful correlation of the bone scan results with clinical history and physical findings, blood cultures, and roentgenography will significantly reduce these problems.

  7. Differential scanning calorimetry of the effects of temperature and humidity on phenol-formaldehyde resin cure

    Treesearch

    X.-M. Wang; B. Riedl; A.W. Christiansen; R.L. Geimer

    1994-01-01

    Phenol-formaldehyde (PF) resin is a widely used adhesive in the manufacture of wood composites. However, curing behaviour of the resin under various environmental conditions is not well known. A differential scanning calorimeter was employed to characterize the degree of resin cure in this study. Resin-impregnated glass cloth samples with varied moisture contents (0,31...

  8. Functional Scanning Probe Imaging of Nanostructured Solar Energy Materials.

    PubMed

    Giridharagopal, Rajiv; Cox, Phillip A; Ginger, David S

    2016-09-20

    From hybrid perovskites to semiconducting polymer/fullerene blends for organic photovoltaics, many new materials being explored for energy harvesting and storage exhibit performance characteristics that depend sensitively on their nanoscale morphology. At the same time, rapid advances in the capability and accessibility of scanning probe microscopy methods over the past decade have made it possible to study processing/structure/function relationships ranging from photocurrent collection to photocarrier lifetimes with resolutions on the scale of tens of nanometers or better. Importantly, such scanning probe methods offer the potential to combine measurements of local structure with local function, and they can be implemented to study materials in situ or devices in operando to better understand how materials evolve in time in response to an external stimulus or environmental perturbation. This Account highlights recent advances in the development and application of scanning probe microscopy methods that can help address such questions while filling key gaps between the capabilities of conventional electron microscopy and newer super-resolution optical methods. Focusing on semiconductor materials for solar energy applications, we highlight a range of electrical and optoelectronic scanning probe microscopy methods that exploit the local dynamics of an atomic force microscope tip to probe key properties of the solar cell material or device structure. We discuss how it is possible to extract relevant device properties using noncontact scanning probe methods as well as how these properties guide materials development. Specifically, we discuss intensity-modulated scanning Kelvin probe microscopy (IM-SKPM), time-resolved electrostatic force microscopy (trEFM), frequency-modulated electrostatic force microscopy (FM-EFM), and cantilever ringdown imaging. We explain these developments in the context of classic atomic force microscopy (AFM) methods that exploit the physics of

  9. A dynamic scanning method based on signal-statistics for scanning electron microscopy.

    PubMed

    Timischl, F

    2014-01-01

    A novel dynamic scanning method for noise reduction in scanning electron microscopy and related applications is presented. The scanning method dynamically adjusts the scanning speed of the electron beam depending on the statistical behavior of the detector signal and gives SEM images with uniform and predefined standard deviation, independent of the signal value itself. In the case of partially saturated images, the proposed method decreases image acquisition time without sacrificing image quality. The effectiveness of the proposed method is shown and compared to the conventional scanning method and median filtering using numerical simulations.

  10. [Vein Scanning Projection Instrument Based on Two-Dimensional Scanning Mirror].

    PubMed

    Meng, Ya; Wu, Zhichao; Xu, Changping; Qian, Yinbo

    2015-09-01

    With the development of science and technology, new medical equipments is toward the direction of intelligent and portable. In order to assist medical personnel to patients with blood, developing from previous devices, a new kind of vein locating projection instrument based on two-dimensional scanning mirror is put forward. It can scan and project vein image using a scanning mirror. The related algorithm is also be improved, make vein scan projection more practical. The system finally set up can perform well in vein scan projection.

  11. A microprocessor controlled pressure scanning system

    NASA Technical Reports Server (NTRS)

    Anderson, R. C.

    1976-01-01

    A microprocessor-based controller and data logger for pressure scanning systems is described. The microcomputer positions and manages data from as many as four 48-port electro-mechanical pressure scanners. The maximum scanning rate is 80 pressure measurements per second (20 ports per second on each of four scanners). The system features on-line calibration, position-directed data storage, and once-per-scan display in engineering units of data from a selected port. The system is designed to be interfaced to a facility computer through a shared memory. System hardware and software are described. Factors affecting measurement error in this type of system are also discussed.

  12. Gigahertz-band electronically scanned antennas

    NASA Astrophysics Data System (ADS)

    Bei, Nikolai A.

    2000-12-01

    Foundation and principles of radio lenses construction of centimeter and millimeter wave ranges with controlled refracting index, combining the quality of phased array antennas with optical devices are stated. Possibilities of the electronically scanning with wide-angle sector and high gain are maintained. Construction principles of scanning antennas with controlled lenses, combining the quality of phased array antennas with optical devices, are stated. Possibilities of electronically scanning with broad angle sector and high gain are maintained. Some examples of construction of antennas millimeter range of waves are listed here.

  13. HEAO-A nominal scanning observation schedule

    NASA Technical Reports Server (NTRS)

    Fishman, G. J.; Stone, R. L.

    1977-01-01

    The HEAO-A observatory, scheduled for launch in late June 1977, will spend most of its orbital lifetime in a scanning mode, spining from 0.03 to 0.1 rpm about an axis aligned with the sun. The dates of availability in the scan band are given for a list of 248 X-ray sources. Celestial maps of source locations and scan planes, and examples of the nighttime elevation of available sources are presented. This document is intended to aid ground-based observers in planning coordinated observations with HEAO-A.

  14. Scanning and georeferencing historical USGS quadrangles

    USGS Publications Warehouse

    Davis, Larry R.; Allord, G.J.

    2011-01-01

    The USGS Historical Quadrangle Scanning Project (HQSP) is scanning all scales and all editions of approximately 250,000 topographic maps published by the U.S. Geological Survey (USGS) since the inception of the topographic mapping program in 1884. This scanning will provide a comprehensive digital repository of USGS topographic maps, available to the public at no cost. This project serves the dual purpose of creating a master catalog and digital archive copies of the irreplaceable collection of topographic maps in the USGS Reston Map Library as well as making the maps available for viewing and downloading from the USGS Store and The National Map Viewer.

  15. Clinical applications of Genome Polymorphism Scans

    PubMed Central

    Weber, James L

    2006-01-01

    Applications of Genome Polymorphism Scans range from the relatively simple such as gender determination and confirmation of biological relationships, to the relatively complex such as determination of autozygosity and propagation of genetic information throughout pedigrees. Unlike nearly all other clinical DNA tests, the Scan is a universal test – it covers all people and all genes. In balance, I argue that the Genome Polymorphism Scan is the most powerful, affordable clinical DNA test available today. Reviewers: This article was reviewed by Scott Weiss (nominated by Neil Smalheiser), Roberta Pagon (nominated by Jerzy Jurka) and Val Sheffield (nominated by Neil Smalheiser). PMID:16756678

  16. Scanning-Pencil-Beam Radar Scatterometer

    NASA Technical Reports Server (NTRS)

    Long, David G.; Freilich, Michael H.; Leotta, Daniel F.; Noon, Don E.

    1992-01-01

    SCANSCAT conceptual scanning radar scatterometer placed in nearly polar orbit around Earth at altitude of 705 km aboard Spacecraft B of NASA's Earth Observing System. Measures radar backscattering from surface of ocean. Data processed on ground into normalized radar-backscattering cross sections, then processed into velocities of winds near surface of ocean by use of empirical mathematical model of relationship between normalized backscattering cross section, wind vector at scanned spot, and angle of incidence and azimuth angle of radar beam. Accuracy and coverage exceeds those of fan-beam scatterometer. Modified versions of scanning plan useful in laser inspection of surface finishes on machined parts.

  17. Scanning-Pencil-Beam Radar Scatterometer

    NASA Technical Reports Server (NTRS)

    Long, David G.; Freilich, Michael H.; Leotta, Daniel F.; Noon, Don E.

    1992-01-01

    SCANSCAT conceptual scanning radar scatterometer placed in nearly polar orbit around Earth at altitude of 705 km aboard Spacecraft B of NASA's Earth Observing System. Measures radar backscattering from surface of ocean. Data processed on ground into normalized radar-backscattering cross sections, then processed into velocities of winds near surface of ocean by use of empirical mathematical model of relationship between normalized backscattering cross section, wind vector at scanned spot, and angle of incidence and azimuth angle of radar beam. Accuracy and coverage exceeds those of fan-beam scatterometer. Modified versions of scanning plan useful in laser inspection of surface finishes on machined parts.

  18. Comparison of full-scan and half-scan for cone beam breast CT imaging

    NASA Astrophysics Data System (ADS)

    Chen, Lingyun; Shaw, Chris C.; Lai, Chao-jen; Altunbas, Mustafa C.; Wang, Tianpeng; Tu, Shu-ju; Liu, Xinming

    2006-03-01

    The half-scan cone beam technique, requiring a scan for 180° plus detector width only, can help achieve both shorter scan time as well as higher exposure in each individual projection image. This purpose of this paper is to investigate whether half-scan cone beam CT technique can provide acceptable images for clinical application. The half-scan cone beam reconstruction algorithm uses modified Parker's weighting function and reconstructs from slightly more than half of the projection views for full-scan, giving out promising results. A rotation phantom, stationary gantry bench top system was built to conduct experiments to evaluate half-scan cone beam breast CT technique. A post-mastectomy breast specimen, a stack of lunch meat slices embedded with various sizes of calcifications and a polycarbonate phantom inserted with glandular and adipose tissue equivalents are imaged and reconstructed for comparison study. A subset of full-scan projection images of a mastectomy specimen were extracted and used as the half-scan projection data for reconstruction. The results show half-scan reconstruction algorithm for cone beam breast CT images does not significantly degrade image quality when compared with the images of same or even half the radiation dose level. Our results are encouraging, emphasizing the potential advantages in the use of half-scan technique for cone beam breast imaging.

  19. Environmental Management

    SciTech Connect

    2014-11-12

    Another key aspect of the NNSS mission is Environmental Management program, which addresses the environmental legacy from historic nuclear weapons related activities while also ensuring the health and safety of present day workers, the public, and the environment as current and future missions are completed. The Area 5 Radioactive Waste Management site receives low-level and mixed low-level waste from some 28 different generators from across the DOE complex in support of the legacy clean-up DOE Environmental Management project. Without this capability, the DOE would not be able to complete the clean up and proper disposition of these wastes. The program includes environmental protection, compliance, and monitoring of the air, water, plants, animals, and cultural resources at the NNSS. Investigation and implementation of appropriate corrective actions to address the contaminated ground water facilities and soils resulting from historic nuclear testing activities, the demolition of abandoned nuclear facilities, as well as installation of ground water wells to identify and monitor the extent of ground water contamination.

  20. Environmental Quality

    ERIC Educational Resources Information Center

    Abelson, Philip H.

    1972-01-01

    Data from the Third Annual Report of the United States Council of Environmental Quality are used in an editorial advocating the use of some of the money committed to cleaning air and water to create a more adequate knowledge base for action. (AL)

  1. Environmental Pollutants

    USDA-ARS?s Scientific Manuscript database

    Managing animal production systems to reduce environmental impacts is most difficult for air quality. Water and soil quality responses to animal production can be managed through planning and understanding the risk of spills, overapplication, or improper use of manure. Escape of gaseous or particula...

  2. Environmental Education.

    ERIC Educational Resources Information Center

    Falkenstein, W. J.

    To assist teachers in knowing about environmental study and their availability for class studies, the West Linn, Oregon School District #3 has developed this "first step" survey. Information for each local study area describes its history, general physical appearance, vegetation, wildlife, special features, present physical development, seasonal…

  3. Environmental Science

    ERIC Educational Resources Information Center

    Eads, Ewin A.

    1973-01-01

    Discusses implementation of an interdisciplinary bachelor of science degree program in Lamar University, Beaumont, with emphases upon the training of pollution and environmental quality control. Indicates that graduates' job opportunities are created by the enactment of recent laws for cleaner air and water. (CC)

  4. Environmental Trends.

    ERIC Educational Resources Information Center

    Council on Environmental Quality, Washington, DC.

    This document consists of data which highlight trends in all sectors relevant to environmental policy. These data are presented in the form of charts and maps contained in 13 sections under the following headings: people and the land; critical areas (wetlands, wild areas, parks, historic places, and risk zones); human settlements; transportation;…

  5. Environmental Management

    ScienceCinema

    None

    2016-07-12

    Another key aspect of the NNSS mission is Environmental Management program, which addresses the environmental legacy from historic nuclear weapons related activities while also ensuring the health and safety of present day workers, the public, and the environment as current and future missions are completed. The Area 5 Radioactive Waste Management site receives low-level and mixed low-level waste from some 28 different generators from across the DOE complex in support of the legacy clean-up DOE Environmental Management project. Without this capability, the DOE would not be able to complete the clean up and proper disposition of these wastes. The program includes environmental protection, compliance, and monitoring of the air, water, plants, animals, and cultural resources at the NNSS. Investigation and implementation of appropriate corrective actions to address the contaminated ground water facilities and soils resulting from historic nuclear testing activities, the demolition of abandoned nuclear facilities, as well as installation of ground water wells to identify and monitor the extent of ground water contamination.

  6. Environmental Science

    ERIC Educational Resources Information Center

    Eads, Ewin A.

    1973-01-01

    Discusses implementation of an interdisciplinary bachelor of science degree program in Lamar University, Beaumont, with emphases upon the training of pollution and environmental quality control. Indicates that graduates' job opportunities are created by the enactment of recent laws for cleaner air and water. (CC)

  7. Environmental Education.

    ERIC Educational Resources Information Center

    Heiser, Ed

    Furnished in this comprehensive report is a resume of a five-year experimental program in environmental education conducted by the Eastern Montana College Laboratory School in conjunction with Eastern Montana College and the Billings School District #2. The basic purpose of the program is to make teachers, and in turn students, aware of the…

  8. Environmental Controls.

    ERIC Educational Resources Information Center

    Schneiderman, Helen, Ed.

    1994-01-01

    Environmental control units, or ECUs, are devices or systems which allow for alternate access to electronic or electrical devices and those objects, like draperies and doors, which may be adapted for use with electricity. Such devices offer the person with a mobility limitation the opportunity to control his or her environment, thus enhancing the…

  9. New Microscope Scans Breast Tumors During Surgery

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_166925.html New Microscope Scans Breast Tumors During Surgery The instrument ... 2017 WEDNESDAY, June 28, 2017 (HealthDay News) -- A new microscope could help surgeons remove breast tumors completely, ...

  10. Getting a CAT Scan (For Kids)

    MedlinePlus

    ... axial tomography." Translated, that means a scanner takes computer pictures of what's going on inside your body. The scan itself is ... Policy Privacy Policy & Terms of Use Visit the Nemours Web ...

  11. Indium-111 leukocyte scanning and fracture healing

    SciTech Connect

    Mead, L.P.; Scott, A.C.; Bondurant, F.J.; Browner, B.D. )

    1990-01-01

    This study was undertaken to determine the specificity of indium-111 leukocyte scans for osteomyelitis when fractures are present. Midshaft tibial osteotomies were performed in 14 New Zealand white rabbits, seven of which were infected postoperatively with Staphylococcus aureus per Norden's protocol. All 14 rabbits were scanned following injection with 75 microCi of indium 111 at 72 h after osteotomy and at weekly intervals for 4 weeks. Before the rabbits were killed, the fracture sites were cultured to document the presence or absence of infection. The results of all infected osteotomy sites were positive, whereas no positive scans were found in the noninfected osteotomies. We concluded from this study that uncomplicated fracture healing does not result in a positive indium-111 leukocyte scan.

  12. Noncontact dimensional measurement system using holographic scanning

    NASA Astrophysics Data System (ADS)

    Sagan, Stephen F.; Rosso, Robert S.; Rowe, David M.

    1997-07-01

    Holographic scanning systems have been used for years in point-of-sale bar code scanners and other low resolution applications. These simple scanning systems could not successfully provide the accuracy and precision required to measure, inspect and control the production of today's high tech optical fibers, medical extrusions and electrical cables. A new class of instruments for the precision measurement of industrial processes has been created by the development of systems with a unique combination of holographic optical elements that can compensate for the wavelength drift in laser diodes, the application of proprietary post-processing algorithms, and the advancements in replication methods to fabricate low cost holographic scanning discs. These systems have improved upon the performance of traditional polygon mirror scanners. This paper presents the optical configuration and design features that have been incorporated into a holographic scanning inspection system that provides higher productivity, increased product quality and lower production costs for many manufacturers.

  13. ReachScan - an Exposure Assessment Model

    EPA Pesticide Factsheets

    ReachScan estimates surface water concentrations downstream from industrial sites to assess impacts on the aquatic environment and potential dose rates for humans exposed via ingestion of drinking water and fish.

  14. Intelligent Classification and Visualization of Network Scans

    SciTech Connect

    Chen, L; Muelder, C; Ma, K; Bartoletti, A

    2007-03-01

    Network scans are a common first step in a network intrusion attempt. In order to gain information about a potential network intrusion, it is beneficial to analyze these network scans. Statistical methods such as wavelet scalogram analysis have been used along with visualization techniques in previous methods. However, applying these statistical methods to reduce the data causes a substantial amount of data loss. This paper presents a study of using associative memory learning techniques to directly compare network scans in order to create a classification which can be used by itself or in conjunction with existing visualization techniques to better characterize the sources of these scans. This produces an integrated system of visual and intelligent analysis which is applicable to real world data.

  15. The design of laser scanning galvanometer system

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoling; Zhou, Bin; Xie, Weihao; Zhang, Yuangeng

    2015-02-01

    In this paper, we designed the laser scanning galvanometer system according to our requirements. Based on scanning range of our laser scanning galvanometer system, the design parameters of this system were optimized. During this work, we focused on the design of the f-θ field lens. An optical system of patent lens in the optical manual book, which had three glasses structure, was used in our designs. Combining the aberration theory, the aberration corrections and image quality evaluations were finished using Code V optical design software. An optimum f-θ field lens was designed, which had focal length of 434 mm, pupil diameter of 30 mm, scanning range of 160 mm × 160 mm, and half field angle of 18°×18°. At the last, we studied the influences of temperature changes on our system.

  16. C-scan ultrasonography in orbital diagnosis.

    PubMed Central

    Restori, M; Wright, J E

    1977-01-01

    A C-scan imaging facility has recently been added to the ultrasonic system in use at Moorfields Eye Hospital, London. The technique is explained and typical C-scans are presented to demonstrate the normal orbital fat and optic nerve, together with selected pathological conditions in the orbit. The C-scan facility permits imaging of the orbital contents in the coronal plane. This coronal plane imaging, together with high resolution and sensitivity, makes this a useful technique for demonstrating orbital lesions and it is hoped helps in the accurate measurement of the diameters of the optic nerve along its length. The problems associated with C-scanning are discussed. Images PMID:603781

  17. New form of scanning optical microscopy

    SciTech Connect

    Reddick, R.C.; Warmack, R.J.; Ferrell, T.L.

    1989-01-01

    The exponential decay of the evanescent field due to the total internal reflection (TIR) of a light beam in a prism is used to advantage in a new form of scanning optical microscope, the photon scanning tunneling microscope (PSTM). The PSTM is the photon analogue of the electron scanning tunneling microscope. The sample is placed on or forms the TIR surface and spatially modulates the evanescent field. Changes in intensity are monitored by a probe tip scanned over the surface, and the data are processed to generate an image of the sample. Subwavelength resolution in three dimensions is obtained because of the exponential nature of the evanescent field intensity. Images produced by a prototype instrument using 633-nm light and a 1-..mu..m probe tip are shown to have a lateral resolution of about 200 nm.

  18. Ocular Health (OH) Ultrasound 2 Scan

    NASA Image and Video Library

    2013-06-06

    Astronaut Karen Nyberg,Expedition 37 flight engineer, assisted by astronaut Chris Cassidy, performs an Ocular Health (OH) Ultrasound 2 scan in the Destiny laboratory of the International Space Station.

  19. System and Method for Scan Range Gating

    NASA Technical Reports Server (NTRS)

    Zuk, David M. (Inventor); Lindemann, Scott (Inventor)

    2017-01-01

    A system for scanning light to define a range gated signal includes a pulsed coherent light source that directs light into the atmosphere, a light gathering instrument that receives the light modified by atmospheric backscatter and transfers the light onto an image plane, a scanner that scans collimated light from the image plane to form a range gated signal from the light modified by atmospheric backscatter, a control circuit that coordinates timing of a scan rate of the scanner and a pulse rate of the pulsed coherent light source so that the range gated signal is formed according to a desired range gate, an optical device onto which an image of the range gated signal is scanned, and an interferometer to which the image of the range gated signal is directed by the optical device. The interferometer is configured to modify the image according to a desired analysis.

  20. Electron Beam Scanning in Industrial Applications

    NASA Astrophysics Data System (ADS)

    Jongen, Yves; Herer, Arnold

    1996-05-01

    Scanned electron beams are used within many industries for applications such as sterilization of medical disposables, crosslinking of wire and cables insulating jackets, polymerization and degradation of resins and biomaterials, modification of semiconductors, coloration of gemstones and glasses, removal of oxides from coal plant flue gasses, and the curing of advanced composites and other molded forms. X-rays generated from scanned electron beams make yet other applications, such as food irradiation, viable. Typical accelerators for these applications range in beam energy from 0.5MeV to 10 MeV, with beam powers between 5 to 500kW and scanning widths between 20 and 300 cm. Since precise control of dose delivery is required in many of these applications, the integration of beam characteristics, product conveyance, and beam scanning mechanisms must be well understood and optimized. Fundamental issues and some case examples are presented.