Science.gov

Sample records for non-destructive pollution exposure

  1. Non-destructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): II. Hair and spines as indicators of endogenous metal and As concentrations.

    PubMed

    D'Havé, Helga; Scheirs, Jan; Mubiana, Valentine Kayawe; Verhagen, Ron; Blust, Ronny; De Coen, Wim

    2006-08-01

    The role of hair and spines of the European hedgehog as non-destructive monitoring tools of metal (Ag, Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, Zn) and As pollution in terrestrial ecosystems was investigated. Our results showed that mean pollution levels of a random sample of hedgehogs in Flanders are low to moderate. Yet, individual hedgehogs may be at risk for metal toxicity. Tissue distribution analyses (hair, spines, liver, kidney, muscle and fat tissue) indicated that metals and As may reach considerable concentrations in external tissues, such as hair and spines. Positive relationships were observed between concentrations in hair and those in liver, kidney and muscle for Al, Co, Cr, Cu, and Pb (0.43 < r < 0.85). Spine concentrations were positively related to liver, kidney and muscle concentrations for Cd, Co, Cr, Cu and Pb (0.37 < r < 0.62). Hair Ag, As, Fe and Zn and spine Ag, Al, As and Fe were related to metal concentrations in one or two of the investigated internal tissues (0.31 < r < 0.45). The regression models presented here may be used to predict metal and As concentrations in internal tissues of hedgehogs when concentrations in hair or spines are available. The present study demonstrated the possibility of using hair and spines for non-destructive monitoring of metal and As pollution in hedgehogs.

  2. Non-destructive method for determining neutron exposure

    DOEpatents

    Gold, R.; McElroy, W.N.

    1983-11-01

    A non-destructive method for determination of neutron exposure in an object, such as a reactor pressure vessel, is based on the observation of characteristic gamma-rays emitted by activation products in the object by using a unique continuous gamma-ray spectrometer. The spectrometer views the object through appropriate collimators to determine the absolute emission rate of these characteristic gamma-rays, thereby ascertaining the absolute activity of given activation products in the object. These data can then be used to deduce the spatial and angular dependence of neutron exposure at regions of interest within the object.

  3. Non-destructive assessment of polycyclic aromatic hydrocarbon (PAH) exposure by fluorimetric analysis of crab urine.

    PubMed

    Koenig, Samuel; Savage, Candida; Kim, Jonathan P

    2008-12-01

    The detection of urinary polycyclic aromatic hydrocarbon (PAH) metabolites by fluorescence spectrophotometry is particularly effective as a practical means to assess PAH exposure in decapod crabs. However, the practical application of this technique has thus far only been tested for the European shore crab (Carcinus maenas) and only a few field studies have been conducted in heavily polluted areas. The present study evaluated the adaptability of this method as a rapid, cost-effective and non-destructive biomonitoring tool for the New Zealand crab species, Macrophthalmus hirtipes (stalk-eyed mud crab). A field gradient could be detected among the sites and different input sources of PAH contamination could be discerned through the differentiation of pyrogenic and petrogenic PAH signatures. The present study shows that the fluorescence screening method is sensitive to relatively low levels of PAH contamination and more broadly applicable to smaller crab species than C. maenas, for which the technique was developed.

  4. Can predatory bird feathers be used as a non-destructive biomonitoring tool of organic pollutants?

    PubMed Central

    Jaspers, Veerle L.B; Voorspoels, Stefan; Covaci, Adrian; Eens, Marcel

    2006-01-01

    The monitoring of different types of pollutants that are released into the environment and that present risks for both humans and wildlife has become increasingly important. In this study, we examined whether feathers of predatory birds can be used as a non-destructive biomonitor of organic pollutants. We demonstrate that polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and polybrominated diphenyl ethers (PBDEs) are measurable in one single tail feather of common buzzards (Buteo buteo) and that levels in this feather and internal tissues are significantly related to each other (0.35non-destructive biomonitoring of organic pollutants, although further validation may be necessary. PMID:17148383

  5. Non-destructive method for determining neutron exposure and constituent concentrations of a body

    DOEpatents

    Gold, Raymond; McElroy, William N.

    1986-01-01

    A non-destructive method for determination of neutron exposure and constituent concentrations in an object, such as reactor pressure vessel, is based on the observation of characteristic gamma-rays emitted by activation products in the object by using a unique continuous gamma-ray spectrometer. The spectrometer views the object through appropriate collimators to determine the absolute emission rate of these characteristic gamma-rays, thereby ascertaining the absolute activity of given activation products in the object. These data can then be used to deduce the spatial and angular dependence of neutron exposure or the spatial constituent concentration at regions of interest within the object.

  6. Non-destructive method for determining neutron exposure and constituent concentrations of a body

    DOEpatents

    Gold, R.; McElroy, W.N.

    1984-02-22

    A non-destructive method for determination of neutron exposure and constituent concentrations in an object, such as a reactor pressure vessel, is based on the observation of characteristic gamma-rays emitted by activation products in the object by using a unique continuous gamma-ray spectrometer. The spectrometer views the object through appropriate collimators to determine the absolute emission rate of these characteristic gamma-rays, thereby ascertaining the absolute activity of given activation products in the object. These data can then be used to deduce the spatial and angular dependence of neutron exposure or the spatial constituent concentrations at regions of interest within the object.

  7. Experimental evaluation of the usefulness of feathers as a non-destructive biomonitor for polychlorinated biphenyls (PCBs) using silastic implants as a novel method of exposure.

    PubMed

    Van den Steen, E; Covaci, A; Jaspers, V L B; Dauwe, T; Voorspoels, S; Eens, M; Pinxten, R

    2007-02-01

    Risk assessment of pollutants requires both monitoring studies in the field and experimental exposure studies. In this study, we evaluated silastic implants as an alternative method of exposure for use in toxicological studies and at the same time evaluated the usefulness of feathers as a non-destructive biomonitor for PCBs. European starlings (Sturnus vulgaris) were exposed to different doses (including a control group) of environmentally relevant concentrations of PCB 153 during a 15-week period using silastic implants with both ends/only one end sealed. After implantation, there was a rapid and significant increase in PCB 153 blood concentration in the exposed groups. The significant differences in blood concentrations among the treatment groups show that silastic implants are useful as a method of exposure. Moreover, the ratio between the tissue concentrations of two treatment groups reflected the difference in implantation doses between these groups. There was also a clear difference in tissue concentrations among the treatment groups, although we could not test this statistically due to the small sample sizes. The slow release kinetics for a prolonged period and the relatively stable blood concentrations during the 15-week period render silastic tubes very interesting to study the effects of chronic exposure to pollutants. Our results also revealed that sealing both ends of the implant instead of only one did not significantly affect the exposure. There were strong, significant positive correlations between the blood and the tissues, which confirm the use of blood to monitor PCBs. To evaluate the usefulness of feathers as a non-destructive biomonitor for PCBs, we plucked the original and newly grown wing and tail feathers. We observed strong, significant positive correlations between the concentrations in the newly grown feathers and concentrations in the muscle, liver, brain and blood. PCB 153 concentrations in the newly grown feathers differed among the

  8. A NEW NON-DESTRUCTIVE METHOD FOR CHEMICAL ANALYSIS OF PARTICULATE MATTER FILTERS: THE CASE OF MANGANESE AIR POLLUTION IN VALLECAMONICA (ITALY)

    PubMed Central

    Borgese, Laura; Zacco, Annalisa; Pal, Sudipto; Bontempi, Elza; Lucchini, Roberto; Zimmerman, Neil; Depero, Laura E.

    2011-01-01

    Total Reflection X-ray Fluorescence (TXRF) is a well-established technique for chemical analysis, but it is mainly employed for quality control in the electronics semiconductor industry. The capability to analyze liquid and uniformly thin solid samples makes this technique suitable for other applications, and especially in the very critical field of environmental analysis. Comparison with standard methods like Inductively Coupled Plasma (ICP) and Atomic Absorption Spectroscopy (AAS) show that TXRF is a practical, accurate, and reliable technique in occupational settings. Due to the greater sensitivity necessary in trace heavy metal detection, TXRF is also suitable for environmental chemical analysis. In this paper we show that based on appropriate standards, TXRF can be considered for non-destructive routine quantitative analysis of environmental matrices such as air filters. This work has been developed in the frame of the EU-FP6 PHIME (Public Health Impact of long-term, low-level Mixed element Exposure in susceptible population strata) Integrated Project (www.phime.org). The aim of this work was to investigate Mn air pollution in the area of Vallecamonica (Italy). PMID:21315919

  9. Air Pollution Exposure

    PubMed Central

    Balmes, John R.; Collard, Harold R.

    2015-01-01

    Air pollution exposure is a well-established risk factor for several adverse respiratory outcomes, including airways diseases and lung cancer. Few studies have investigated the relationship between air pollution and interstitial lung disease (ILD) despite many forms of ILD arising from environmental exposures. There are potential mechanisms by which air pollution could cause, exacerbate, or accelerate the progression of certain forms of ILD via pulmonary and systemic inflammation as well as oxidative stress. This article will review the current epidemiologic and translational data supporting the plausibility of this relationship and propose a new conceptual framework for characterizing novel environmental risk factors for these forms of lung disease. PMID:25846532

  10. Atlantis Non-destructive Testing

    NASA Image and Video Library

    2003-10-29

    In the Orbiter Processing Facility, the nose cap (foreground) removed from Atlantis (behind) waits to be shipped to the original manufacturing company, Vought in Ft. Worth, Texas, a subsidiary of Lockheed Martin, to undergo non-destructive testing such as CAT scan and thermography.

  11. Non-Destructive Testing Scanner

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Bio-Imaging Research's technology that originated in an aerospace program has come full circle with a new aerospace adaptation called the Advanced Computed Tomography Inspection System, or ACTIS. The medical version of CT scans the human body for tumors or other abnormalities, the ACTIS system finds imperfections in aerospace structures and components, such as castings, assemblies, rocket motors and nozzles. ACTIS is described by its developer as the most versatile CT scanner available for non-destructive testing applications. ACTIS is a variable geometry system. ACTIS source and detectors can be moved closer together or farther apart to optimize the geometry for different sizes of test objects. The combination of variable geometry, three sources, and focusing detectors makes ACTIS cost effective for a broad range of applications. System can scan anything from very small turbine blades to large rocket assemblies.

  12. Non-destructive identification of twisted light.

    PubMed

    Li, Pengyun; Wang, Bo; Song, Xinbing; Zhang, Xiangdong

    2016-04-01

    The non-destructive identification of the orbital angular momentum (OAM) is essential to various applications in the optical information processing. Here, we propose and demonstrate experimentally an efficient method to identify non-destructively the OAM by using a modified Mach-Zehnder interferometer. Our schemes are applicable not only to the case with integer charges, but also to optical vortices with noninteger charges. Our Letter presents the first experimental demonstration of the non-destructive identification of twisted light with integer or noninteger topological charges, which has potential applications in the OAM-based data transmission for optical communications.

  13. Method for non-destructive testing

    DOEpatents

    Akers, Douglas W [Idaho Falls, ID

    2011-08-30

    Non-destructive testing method may include providing a source material that emits positrons in response to bombardment of the source material with photons. The source material is exposed to photons. The source material is positioned adjacent the specimen, the specimen being exposed to at least some of the positrons emitted by the source material. Annihilation gamma rays emitted by the specimen are detected.

  14. Hybrid holographic non-destructive test system

    NASA Technical Reports Server (NTRS)

    Kurtz, R. L. (Inventor)

    1978-01-01

    An automatic hybrid holographic non-destructive testing (HNDT) method and system capable of detecting flaws or debonds contained within certain materials are described. This system incorporates the techniques of optical holography, acoustical/optical holography and holographic correlation in determining the structural integrity of a test object. An automatic processing system including a detector and automatic data processor is used in conjunction with the three holographic techniques for correlating and interpreting the information supplied by the non-destructive systems. The automatic system also includes a sensor which directly translates an optical data format produced by the holographic techniques into electrical signals and then transmits this information to a digital computer for indicating the structural properties of the test object. The computer interprets the data gathered and determines whether further testing is necessary as well as the format of this new testing procedure.

  15. Non-Destructive State Machine Reverse Engineering

    SciTech Connect

    Smith, Jessica L.

    2013-10-10

    Most of the integrated circuits (ICs) that are in electronic systems today are based on state machines. We are taking advantage of this to develop a hardware reverse engineering method that discovers the IC’s underlying state machine, rather than its transistors and gates. While there are other methods for destructively reverse engineering ICs or for non-destructively characterizing ICs, our method offers a fast and accurate analysis while remaining non-destructive. To do this, we present an intelligent brute-force method of exploring the logic of the IC using only the input and outputs designed into the IC - the I/O pins. From this exploration, we can apply a folding algorithm to discover the designed state machine.

  16. Non-Destructive Evaluation of Aerospace Composites

    DTIC Science & Technology

    2009-03-01

    Master of Science in Materials Science Jeremy D. Johnson, BS Captain, USAF March 2009 APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED...non-destructive material evaluation (NDE) were used to inspect various forms of damage commonly found in aerospace fiberglass composites: voids...ultrasound, and flash IR thermography were analyzed for the detection of defects. Test results and analysis of each NDE method’s capabilities

  17. FIRST 100 T NON-DESTRUCTIVE MAGNET

    SciTech Connect

    J. R. SIMS; ET AL

    1999-10-01

    The first 100 T non-destructive (100 T ND) magnet and power supplies as currently designed are described. This magnet will be installed as part of the user facility research equipment at the National High Magnetic Field Laboratory (NHMFL) Pulsed Field Facility at Los Alamos National Laboratory. The 100 T ND magnet will provide a 100 T pulsed field of 5 ms duration (above 90% of full field) in a 15 mm diameter bore once per hour. Magnet operation will be non-destructive. The magnet will consist of a controlled power outer coil set which produces a 47 T platform field in a 225 mm diameter bore. Located within the outer coil set will be a 220 mm outer diameter capacitor powered insert coil. Using inertial energy storage a synchronous motor/generator will provide ac power to a set of seven ac-dc converters rated at 64 MW/80 MVA each. These converters will energize three independent coil circuits to create 170 MJ of field energy in the outer coil set at the platform field of 47 T. The insert will then be energized to produce the balance of the 100 T peak field using a 2.3 MJ, 18 kV (charged to 15 kV), 14.4 mF capacitor bank controlled with solid-state switches. The magnet will be the first of its kind and the first non-destructive, reusable 100 T pulsed magnet. The operation of the magnet will be described along with special features of its design and construction.

  18. Complementary Electromagnetic Non-Destructive Evaluation

    NASA Astrophysics Data System (ADS)

    Tian, Gui Yun; Wilson, John; Morozov, Maxim

    2011-06-01

    The use of non-destructive evaluation (NDE) for defect detection and failure prediction in structures and specimens is widespread in energy industries, aimed at ageing power plants and pipelines, material degradation, fatigue and radiation damage, etc. At present there are no suitable electromagnetic NDE methods for the measurement and characterization of material degradation, in irradiated samples in particular, which is very important and timely for the nuclear power industry in the UK. This paper reports recent developments in the field of electromagnetic (EM) NDE at Newcastle University, including pulsed eddy current (PEC), pulsed magnetic flux leakage (PMFL), magnetic Barkhausen emission (MBE) and magneto-acoustic emission (MAE). As different EM methods have different strengths, an integrative EM framework is introduced. Case studies through the second round robin tests organized by the Universal Network for Magnetic Non-Destructive Evaluation (UNMNDE), representing eighteen leading research groups worldwide in the area of electromagnetic NDE, are reported. Twelve samples with different ageing times and rolling reduction ratios were tested using different magnetic methods among the UNMNDE members. Based on the studies, the complementary characteristics of electromagnetic techniques for NDE are discussed.

  19. Non-destructive testing method and apparatus

    DOEpatents

    Akers, Douglas W [Idaho Falls, ID

    2011-10-04

    Non-destructive testing apparatus may comprise a photon source and a source material that emits positrons in response to bombardment of the source material with photons. The source material is positionable adjacent the photon source and a specimen so that when the source material is positioned adjacent the photon source it is exposed to photons produced thereby. When the source material is positioned adjacent the specimen, the specimen is exposed to at least some of the positrons emitted by the source material. A detector system positioned adjacent the specimen detects annihilation gamma rays emitted by the specimen. Another embodiment comprises a neutron source and a source material that emits positrons in response to neutron bombardment.

  20. NON-DESTRUCTIVE FLAW DETECTION APPARATUS

    DOEpatents

    Stateman, M.J.; Holloway, H.R.

    1957-12-17

    An apparatus is described for the non-destructive detection of flaws in electrical conducting articles. The particular feature of the detection apparatus is that a flaw in the front or back of the test article will not be masked by signals caused by the passage of the end and front of the article through the detection apparatus. The present invention alleviates the above problem by mounting detection coils on directly opposite sides of the test passageway so that the axes of the pickup coils are perpendicular to the axis of an energizing coil through which the article is passed. A flaw in the article will cause a change in the voltage induced in one pickup coil, but passage of the end or front of the article will not produce unequal signals. The signals are compared in appropriate electrical circuitry to actuate a recorder only when unequal signals are present, indicating the presence of a flaw.

  1. Non-destructive evaluation of composites

    NASA Technical Reports Server (NTRS)

    Chu, Tsuchin Philip

    1996-01-01

    The composite materials have been used in aerospace industries for quite some time. Several non-destructive evaluation (NDE) methods have been developed to inspect composites in order to detect flaws, matrix cracking, and delamination. These methods include ultrasonics, acoustic emission, shearography, thermography, X-ray, and digital image correlation. The NDE Branch of Marshall Space Flight Center has recently acquired a thermal imaging NDE system. The same system has been used at NASA Langley Research Center for detecting disbonds. In order to compare different NDE methods, three carbon/carbon composite panels were used for experiment using ultrasonic C-scan, shearography, and thermography methods. These panels have teflon inserts to simulate the delamination between plies in a composite panel. All three methods have successfully located the insert. The experiment and results are presented in the following sections.

  2. Direct and indirect exposure to air pollution.

    PubMed

    Thron, R W

    1996-02-01

    Hazardous substances that originally are discharged as air pollutants may find their pathway to human exposure through multiple routes, including ingestion and dermal contact, as well as direct inhalation. The mechanisms for modeling and understanding the fate of air pollutants through atmospheric transport, deposition into water and soil, bioaccumulation, and ultimate uptake to receptor organs and systems in the human body are complex. Pollution prevention programs can be better engineered, pollution priorities can be identified, and greater environmental public health gains (attributable to pollution prevention) can be achieved by evaluating the multiple pathways to human exposure and through improved dosage calculations. A single contaminant source often may represent only a fraction of a total body pollutant burden. Further research is needed on source culpability and attributable risk, long-range transport of air pollutants, human dose contributions by various pathways, better techniques for health risk assessment, and an identification of human behavior patterns that affect exposure and dose.

  3. Air Pollution Exposure Modeling for Health Studies

    EPA Science Inventory

    Dr. Michael Breen is leading the development of air pollution exposure models, integrated with novel personal sensor technologies, to improve exposure and risk assessments for individuals in health studies. He is co-investigator for multiple health studies assessing the exposure ...

  4. Non destructive testing of soft body armor

    NASA Astrophysics Data System (ADS)

    Bhise, Karan

    Pristine bullet proof vests are extremely effective at halting pre-determined projectile threats and have saved over 3000 lives. However, the effectiveness of these vests to halt a bullet is seen to decrease over time.Owing to the importance of bullet proof vests over a period of time, tests to determine their effectiveness have been carried out on every batch of vests at the time of inception and at certain time intervals by shooting a bullet through them. A few vests from every batch are picked up and shot at to check for bullet penetration during this process while these results are extrapolated onto the other vests from the batch.One of the main issues with this method is the fact that testing a few jackets among a large set of jackets does not guarantee the safety of every jacket in the entire batch.Further the jackets that are shot-at have the possibility of undergoing substantial damage during the process thus compromising its safety rendering them unsafe for future use.As the vest penetration phenomenon is extremely complex too, there arose a need for a better testing procedure that could not only help ensure more safety, but also save time and money.The new testing procedure proposed a non-destructive evaluation of the jackets that would solve the issues previous faced in testing the vests. This would lead to the building of a portable set up which could be carried to any location to test jackets in a matter of minutes thus saving time and money.

  5. Cryogenic Storage Tank Non-Destructive Evaluation

    NASA Technical Reports Server (NTRS)

    Arens, Ellen

    2010-01-01

    This slide presentation reviews the work in non-destructive evaluation (NDE) of cryogenic storage tanks. Four large cryogenic tanks, constructed in 1965 with perlite insulation in the annular regions, are of concern. The construction of the tanks, two Liquid Oxygen (LOX) and two Liquid Hydrogen (LH2), are described. The loss rate for the LOX tank at Pad A is slightly higher than that for the one at Pad B. The concerns for the LH2 tank at Pad B are that there is a significantly higher boil-off rate than that at Pad A, that there is mold growth, indicative of increased heat flow, that there is a long down-time needed for repairs, and that 3 of 5 full thermal cycles have been used on the Pad B LH2 tank. The advantages and disadvantages of thermal imaging are given. A detailed description of what is visible of the structures in the infra-red is given and views of the thermal images are included. Missing Perlite is given as the probable cause of the cold spot on the Pad B LH2 tank. There is no indications of problematic cold regions on the Pad A LH2 tank, as shown by the thermal images given in the presentation. There is definite indication of a cold region on the Pad A LOX tank. There is however concerns with thermal imaging, as thermal images can be significantly effected by environmental conditions, image differences on similar days but with different wind speeds. Other effects that must be considered include ambient temperature, humidity levels/dew, and cloud reflections

  6. Using magnetic levitation for non-destructive quality control of plastic parts.

    PubMed

    Hennek, Jonathan W; Nemiroski, Alex; Subramaniam, Anand Bala; Bwambok, David K; Yang, Dian; Harburg, Daniel V; Tricard, Simon; Ellerbee, Audrey K; Whitesides, George M

    2015-03-04

    Magnetic levitation (MagLev) enables rapid and non-destructive quality control of plastic parts. The feasibility of MagLev as a method to: i) rapidly assess injection-molded plastic parts for defects during process optimization, ii) monitor the degradation of plastics after exposure to harsh environmental conditions, and iii) detect counterfeit polymers by density is demonstrated.

  7. Exposure measurement for air-pollution epidemiology

    SciTech Connect

    Ferris, B.G.; Ware, J.H.; Spengler, J.D.

    1988-08-01

    The chapter describes the evolution of air-pollution epidemiology over a period when changes in pollution technologies have both lowered total exposures and dispersed them over vastly greater areas. Since personal exposure and microenvironmental measurements are expensive, studies oriented toward measurements of total exposure will be smaller and more intensive. The shift in emphasis to total human exposure also will affect health risk assessment and raise difficult issues in the regulatory domain. Considering that outdoor exposures (for which EPA has a regulatory mandate) occur in the context of exposures from other sources, the potential effect of regulatory action would probably be small. The regulatory issues are even more difficult for particulate air pollution since cigarette smoking is the strongest determinant of indoor levels but the EPA lacks regulatory responsibility for cigarette smoke.

  8. NON-DESTRUCTIVE SOIL CARBON ANALYZER.

    SciTech Connect

    Wielopolski, Lucian; Hendrey, G.; Orion, I.; Prior, S.; Rogers, H.; Runion, B.; Torbert, A.

    2004-02-01

    This report describes the feasibility, calibration, and safety considerations of a non-destructive, in situ, quantitative, volumetric soil carbon analytical method based on inelastic neutron scattering (INS). The method can quantify values as low as 0.018 gC/cc, or about 1.2% carbon by weight with high precision under the instrument's configuration and operating conditions reported here. INS is safe and easy to use, residual soil activation declines to background values in under an hour, and no radiological requirements are needed for transporting the instrument. The labor required to obtain soil-carbon data is about 10-fold less than with other methods, and the instrument offers a nearly instantaneous rate of output of carbon-content values. Furthermore, it has the potential to quantify other elements, particularly nitrogen. New instrumentation was developed in response to a research solicitation from the U.S. Department of Energy (DOE LAB 00-09 Carbon Sequestration Research Program) supporting the Terrestrial Carbon Processes (TCP) program of the Office of Science, Biological and Environmental Research (BER). The solicitation called for developing and demonstrating novel techniques for quantitatively measuring changes in soil carbon. The report includes raw data and analyses of a set of proof-of-concept, double-blind studies to evaluate the INS approach in the first phase of developing the instrument. Managing soils so that they sequester massive amounts of carbon was suggested as a means to mitigate the atmospheric buildup of anthropogenic CO{sub 2}. Quantifying changes in the soils' carbon stocks will be essential to evaluating such schemes and documenting their performance. Current methods for quantifying carbon in soil by excavation and core sampling are invasive, slow, labor-intensive and locally destroy the system being observed. Newly emerging technologies, such as Laser Induced Breakdown Spectroscopy and Near-Infrared Spectroscopy, offer soil

  9. Non-Destructive Classification Approaches for Equilibrated Ordinary Chondrites

    NASA Astrophysics Data System (ADS)

    Righter, K.; Harrington, R.; Schroeder, C.; Morris, R. V.

    2013-09-01

    In order to compare a few non-destructive classification techniques with the standard approaches, we have characterized a group of chondrites from the Larkman Nunatak region using magnetic susceptibility and Mössbauer spectroscopy.

  10. NON-DESTRUCTIVE TESTING METHODS FOR GEOTHERMAL PIPING.

    SciTech Connect

    BERNDT,M.L.

    2001-03-23

    Non-destructive testing is a key component of optimized plant inspection and maintenance programs. Risk based inspection, condition based maintenance and reliability centered maintenance systems all require detection, location and sizing of defects or flaws by non-destructive methods. Internal damage of geothermal piping by corrosion and erosion-corrosion is an ongoing problem requiring inspection and subsequent maintenance decisions to ensure safe and reliable performance. Conventional manual ultrasonic testing to determine remaining wall thickness has major limitations, particularly when damage is of a random and localized nature. Therefore, it is necessary to explore alternative non-destructive methods that offer potential benefits in terms of accurate quantification of size, shape and location of damage, probability of detection, ability to use on-line over long ranges, and economics. A review of non-destructive methods and their applicability to geothermal piping was performed. Based on this, ongoing research will concentrate on long range guided wave and dynamic methods.

  11. A Review of Non-destructive Detection for Fruit Quality

    NASA Astrophysics Data System (ADS)

    Gao, Haisheng; Zhu, Fengmei; Cai, Jinxing

    An overview of non-destructive detection in quality of post-harvest fruit was presented in this paper, and the research and application were discussed. This paper elaborated the fruit quality detection methods which were based on one of the following properties: optical properties, sonic vibration, machine vision technique, nuclear magnetic resonance (NMR), electronic noses, electrical properties, computed tomography. At last, the main problems of non-destructive detection in application were also explained.

  12. Biomarkers: Non-destructive Method for Predicting Meat Tenderization.

    PubMed

    Singh, Arashdeep; Ahluwalia, Preeti; Rafiq, Aasima; Sharma, Savita

    2015-07-06

    Meat tenderness is the primary and most important quality attribute for the consumers worldwide. Tenderness is the process of breakdown of collagen tissue in meat to make it palatable. The earlier methods of tenderness evaluation like taste panels and shear force methods are destructive, time consuming and ill suited as they requires removing a piece of steak from the carcass for performing the test. Therefore, a non-destructive method for predicting the tenderness would be more desirable. The development of a meat quality grading and guarantee system through muscle profiling research can help to meet this demand. Biomarkers have the ability to identify if an exposure has occurred. Biomarkers of the meat quality are of prime importance for meat industry, which has ability to satisfy consumers' expectations. The biomarkers so far identified have been then sorted and grouped according to their common biological functions. All of them refer to a series of biological pathways including glycolytic and oxidative energy production, cell detoxification, protease inhibition and production of Heat Shock Proteins. On this basis, a detailed analysis of these metabolic pathways helps in identifying tenderization of meat having some domains of interest. It was, therefore, stressed forward that biomarkers can be used to determine meat tenderness. This review article summarizes the uses of several biomarkers for predicting the meat tenderness.

  13. Personal exposure of children to air pollution

    NASA Astrophysics Data System (ADS)

    Ashmore, M. R.; Dimitroulopoulou, C.

    Changes over recent decades in outdoor concentrations of air pollutants are well documented. However, the impacts of air pollution on an individual's health actually relate not to these outdoor concentrations but to their personal exposure in the different locations in which they spend time. Assessing how personal exposures differ from outdoor concentrations, and how they have changed over recent decades, is challenging. This review focuses on the exposure of children, since they are a particularly sensitive group. Much of children's time is spent indoors, and childhood exposure is closely related to concentrations in the home, at school, and in transport. For this reason, children's personal exposures to air pollutants differ significantly from both those of adults and from outdoor concentrations. They depend on a range of factors, including urbanisation, energy use, building design, travel patterns, and activity profiles; analysis of these factors can identify a wider range of policy measures to reduce children's exposure than direct emission control. There is a very large variation in personal exposure between individual children, caused by differences in building design, indoor and outdoor sources, and activity patterns. Identifying groups of children with high personal exposure, and their underlying causes, is particularly important in regions of the world where emissions are increasing, but there are limited resources for environmental and health protection. Although the science of personal exposure assessment, with the associated measurement and modelling techniques, has developed to maturity in North America and western Europe over the last 50 years, there is an urgent need to apply this science in other parts of the world where the effects of air pollution are now much more serious.

  14. Measurement error in air pollution exposure assessment.

    PubMed

    Navidi, W; Lurmann, F

    1995-01-01

    The exposure of an individual to an air pollutant can be assessed indirectly, with a "microenvironmental" approach, or directly with a personal sampler. Both methods of assessment are subject to measurement error, which can cause considerable bias in estimates of health effects. If the exposure estimates are unbiased and the measurement error is nondifferential, the bias in a linear model can be corrected when the variance of the measurement error is known. Unless the measurement error is quite large, estimates of health effects based on individual exposures appear to be more accurate than those based on ambient levels.

  15. Characterizing climate change impacts on human exposures to air pollutants

    EPA Science Inventory

    Human exposures to air pollutants such as ozone (O3) have the potential to be altered by changes in climate through multiple factors that drive population exposures, including: ambient pollutant concentrations, human activity patterns, population sizes and distributions, and hous...

  16. Characterizing climate change impacts on human exposures to air pollutants

    EPA Science Inventory

    Human exposures to air pollutants such as ozone (O3) have the potential to be altered by changes in climate through multiple factors that drive population exposures, including: ambient pollutant concentrations, human activity patterns, population sizes and distributions, and hous...

  17. NonDestructive Evaluation for Industrial & Development Applications

    SciTech Connect

    Hunter, James F.

    2016-10-12

    Provide overview of weld inspection for Non-Destructive Testing at LANL. This includes radiography (RT/DR/CR/CT for x-ray & neutron sources), ultrasonic testing (UT/PAUT), dye penetrant inspection (PT), eddy current inspection (ET) and magnetic particle testing (MT). Facilities and capabilities for weld inspection will be summarized with examples.

  18. Non-destructive methods for food texture assessment

    USDA-ARS?s Scientific Manuscript database

    Food texture is important to the successful marketing and profitability of food products. Non-destructive sensing would allow food producers and processors to inspect, sort, grade, or track individual product items, so that they can deliver consistent, superior food products to the marketplace. Over...

  19. Elderly exposure to indoor air pollutants

    NASA Astrophysics Data System (ADS)

    Almeida-Silva, M.; Wolterbeek, H. T.; Almeida, S. M.

    2014-03-01

    The aim of this work was to characterize the indoor air quality in Elderly Care Centers (ECCs) in order to assess the elders' daily exposure to air pollutants. Ten ECCs hosting 384 elderly were selected in Lisbon and Loures. Firstly, a time-budget survey was created based on questionnaires applied in the studied sites. Results showed that in average elders spend 95% of their time indoors splitted between bedrooms and living-rooms. Therefore, a set of physical and chemical parameters were measured continuously during the occupancy period in these two indoor micro-environments and in the outdoor. Results showed that indoor was the main environment contributing for the elders' daily exposure living in ECCs. In the indoor, the principal micro-environment contributing for the elders' daily exposure varied between bedrooms and living-rooms depending not only on the characteristics of the ECCs but also on the pollutants. The concentrations of CO2, VOCt, O3 and PM10 exceeded the limit values predominantly due to the insufficient ventilation preconized in the studied sites.

  20. Non-destructive microstructural analysis with depth resolution

    NASA Astrophysics Data System (ADS)

    Zolotoyabko, E.; Quintana, J. P.

    2003-01-01

    A depth-sensitive X-ray diffraction technique has been developed with the aim of studying microstructural modifications in inhomogeneous polycrystalline materials. In that method, diffraction profiles are measured at different X-ray energies varied by small steps. X-rays at higher energies probe deeper layers of material. Depth-resolved structural information is retrieved by comparing energy-dependent diffraction profiles. The method provides non-destructive depth profiling of the preferred orientation, grain size, microstrain fluctuations and residual strains. This technique is applied to the characterization of seashells. Similarly, energy-variable X-ray diffraction can be used for the non-destructive characterization of different laminated structures and composite materials.

  1. Non-destructive examination system of vitreous body

    NASA Astrophysics Data System (ADS)

    Shibata, Takuma; Gong, Jin; Watanabe, Yosuke; Kabir, M. Hasnat; Masato, Makino; Furukawa, Hidemitsu; Nishitsuka, Koichi

    2014-04-01

    Eyeball plays a quite important role in acquiring the vision. Vitreous body occupies the largest part of the eyeball and consists of biological, elastic, transparent, gel materials. In the present medical examination, the non-destructive examination method of the vitreous body has not been well established. Here, we focus on an application of dynamic light scattering to this topic. We tried to apply our lab-made apparatus, scanning microscopic light scattering (SMILS), which was specially designed for observing the nanometer-scale network structure in gel materials. In order to examine the vitreous body using SMILS method, a commercial apparatus, nano Partica (Horiba Co. Ltd.) was also customized. We analyzed vitreous body using both the SMILS and the customized nano Partica. We successfully examined the vitreous bodies of healthy pigs in non-destructive way.

  2. Infrared Thermography for Temperature Measurement and Non-Destructive Testing

    PubMed Central

    Usamentiaga, Rubèn; Venegas, Pablo; Guerediaga, Jon; Vega, Laura; Molleda, Julio; Bulnes, Francisco G.

    2014-01-01

    The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed. PMID:25014096

  3. Infrared thermography for temperature measurement and non-destructive testing.

    PubMed

    Usamentiaga, Rubén; Venegas, Pablo; Guerediaga, Jon; Vega, Laura; Molleda, Julio; Bulnes, Francisco G

    2014-07-10

    The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed.

  4. Non-destructive NIR FT Raman analysis of plants

    NASA Astrophysics Data System (ADS)

    Schrader, B.; Klump, H. H.; Schenzel, K.; Schulz, H.

    1999-10-01

    Non-destructive analyses of animal and plant cells and tissues by 'classical' Raman spectroscopy with excitation in the visible range have not been possible since the samples are destroyed photochemically or their fluorescence conceals the Raman spectra completely. When excited with the Nd:YAG laser line at 1064 nm fluorescence-free Raman spectra of animal or plant cells and tissues can be recorded without special preparation. In this paper we concentrate on plants and its constituents: essential oils, natural dyes, flavors, spices, alkaloids and fibers can be characterized. The spectra allow the observation of biochemical processes, to observe the distribution of natural products, application to taxonomy, optimizing plant breeding, the harvesting time and control of food—everything non-destructively in living plants!

  5. Non-destructive techniques based on eddy current testing.

    PubMed

    García-Martín, Javier; Gómez-Gil, Jaime; Vázquez-Sánchez, Ernesto

    2011-01-01

    Non-destructive techniques are used widely in the metal industry in order to control the quality of materials. Eddy current testing is one of the most extensively used non-destructive techniques for inspecting electrically conductive materials at very high speeds that does not require any contact between the test piece and the sensor. This paper includes an overview of the fundamentals and main variables of eddy current testing. It also describes the state-of-the-art sensors and modern techniques such as multi-frequency and pulsed systems. Recent advances in complex models towards solving crack-sensor interaction, developments in instrumentation due to advances in electronic devices, and the evolution of data processing suggest that eddy current testing systems will be increasingly used in the future.

  6. Non-Destructive Techniques Based on Eddy Current Testing

    PubMed Central

    García-Martín, Javier; Gómez-Gil, Jaime; Vázquez-Sánchez, Ernesto

    2011-01-01

    Non-destructive techniques are used widely in the metal industry in order to control the quality of materials. Eddy current testing is one of the most extensively used non-destructive techniques for inspecting electrically conductive materials at very high speeds that does not require any contact between the test piece and the sensor. This paper includes an overview of the fundamentals and main variables of eddy current testing. It also describes the state-of-the-art sensors and modern techniques such as multi-frequency and pulsed systems. Recent advances in complex models towards solving crack-sensor interaction, developments in instrumentation due to advances in electronic devices, and the evolution of data processing suggest that eddy current testing systems will be increasingly used in the future. PMID:22163754

  7. A non-destructive DNA sampling technique for herbarium specimens.

    PubMed

    Shepherd, Lara D

    2017-01-01

    Herbarium specimens are an important source of DNA for plant research but current sampling methods require the removal of material for DNA extraction. This is undesirable for irreplaceable specimens such as rare species or type material. Here I present the first non-destructive sampling method for extracting DNA from herbarium specimens. DNA was successfully retrieved from robust leaves and/or stems of herbarium specimens up to 73 years old.

  8. Embedded Non-Destructive Evaluation for Glass Armor

    DTIC Science & Technology

    2011-12-05

    Unclassified In House NDE and Electromagnetic Compatibility Capabilities Millimeter wave Scanning Imager Phased Array Ultrasound Immersion Tank Low...DISTRIBUTION A: Approved for public release; distribution is unlimited Embedded NDE for Glass Armor Sensor Enhanced Armor- Non-Destructive...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Unclassified Armor Solutions Tested with Ultrasonics NDT/E leading to Sensor Enhanced

  9. Non-Destructive Testing for Control of Radioactive Waste Package

    NASA Astrophysics Data System (ADS)

    Plumeri, S.; Carrel, F.

    2015-10-01

    Characterization and control of radioactive waste packages are important issues in the management of a radioactive waste repository. Therefore, Andra performs quality control inspection on radwaste package before disposal to ensure the compliance of the radwast characteristics with Andra waste disposal specifications and to check the consistency between Andra measurements results and producer declared properties. Objectives of this quality control are: assessment and improvement of producer radwaste packages quality mastery, guarantee of the radwaste disposal safety, maintain of the public confidence. To control radiological characteristics of radwaste package, non-destructive passive methods (gamma spectrometry and neutrons counting) are commonly used. These passive methods may not be sufficient, for instance to control the mass of fissile material contained inside radwaste package. This is particularly true for large concrete hull of heterogeneous radwaste containing several actinides mixed with fission products like 137Cs. Non-destructive active methods, like measurement of photofission delayed neutrons, allow to quantify the global mass of actinides and is a promising method to quantify mass of fissile material. Andra has performed different non-destructive measurements on concrete intermediate-level short lived nuclear waste (ILW-SL) package to control its nuclear material content. These tests have allowed Andra to have a first evaluation of the performance of photofission delayed neutron measurement and to identify development needed to have a reliable method, especially for fissile material mass control in intermediate-level long lived waste package.

  10. Uncertainty in exposure to air pollution

    NASA Astrophysics Data System (ADS)

    Pebesma, Edzer; Helle, Kristina; Christoph, Stasch; Rasouli, Soora; Timmermans, Harry; Walker, Sam-Erik; Denby, Bruce

    2013-04-01

    To assess exposure to air pollution for a person or for a group of people, one needs to know where the person or group is as a function of time, and what the air pollution is at these times and locations. In this study we used the Albatross activity-based model to assess the whereabouts of people and the uncertainties in this, and a probabilistic air quality system based on TAPM/EPISODE to assess air quality probabilistically. The outcomes of the two models were combined to assess exposure to air pollution, and the errors in it. We used the area around Rotterdam (Netherlands) as a case study. As the outcomes of both models come as Monte Carlo realizations, it was relatively easy to cancel one of the sources of uncertainty (movement of persons, air pollution) in order to identify their respective contributions, and also to compare evaluations for individuals with averages for a population of persons. As the output is probabilistic, and in addition spatially and temporally varying, the visual analysis of the complete results poses some challenges. This case study was one of the test cases in the UncertWeb project, which has built concepts and tools to realize the uncertainty-enabled model web. Some of the tools and protocols will be shown and evaluated in this presentation. For the uncertainty of exposure, the uncertainty of air quality was more important than the uncertainty of peoples locations. This difference was stronger for PM10 than for NO2. The workflow was implemented as generic Web services in UncertWeb that also allow for other inputs than the simulated activity schedules and air quality with other resolution. However, due to this flexibility, the Web services require standardized formats and the overlay algorithm is not optimized for the specific use case resulting in a data and processing overhead. Hence, we implemented the full analysis in parallel in R, for this specific case as the model web solution had difficulties with massive data.

  11. Human exposure to urban air pollution.

    PubMed Central

    Boström, C E; Almén, J; Steen, B; Westerholm, R

    1994-01-01

    This study deals with some methods of making human exposure estimates, aimed at describing the human exposure for selected air pollutants in Sweden that are suspected carcinogens. Nitrogen oxides (NOx) have been chosen as an indicator substance for estimating the concentration of the urban plume. Earlier investigations have shown that the traffic in Swedish cities contributes around 85% to the measured NOx concentrations, and that most of the mutagenicity in urban air originates from traffic. The first section of this paper describes measurements in Stockholm of some unregulated light hydrocarbons, such as ethene, ethyne, propane, propene, butane, and isobutane. In addition, measurements of some volatile aromatic hydrocarbons are presented. Simultaneous measurements of carbon monoxide (CO) were made. The ratios between CO and the individual specific compounds were determined by linear regression analysis. By analysis of relationships between CO and NOx, NOx concentrations can be used as a tracer to describe the exposure for these specific compounds. NOx are considered to be a better tracer than CO, because NOx or NO2 values exist for many places over a long time, while CO is measured mostly in streets with high concentrations. At low concentrations, instruments that measure normal CO levels give no detectable signals. Through use of atmospheric dispersion models and models that describe how people live and work in urban areas it has been possible to describe the average exposure to NOx in cities of different sizes. The exposure to NOx for people living in the countryside has also been estimated. In this way, it has been possible to calculate the average exposure dose for NOx for the Swedish population. This figure is 23 micrograms/m3. By use of the relationships between NOx and specific compounds the average dose has been calculated for the following compounds: polyaromatic compounds (PAH); ethene, propene, and butadiene; benzene, toluene, and xylene; formaldehyde

  12. Controlled human exposures to ambient pollutant particles in susceptible populations

    EPA Science Inventory

    Epidemiologic studies have established an association between exposures to air pollution particles and human mortality and morbidity at concentrations of particles currently found in major metropolitan areas. The adverse effects of pollution particles are most prominent in suscep...

  13. Controlled human exposures to ambient pollutant particles in susceptible populations

    EPA Science Inventory

    Epidemiologic studies have established an association between exposures to air pollution particles and human mortality and morbidity at concentrations of particles currently found in major metropolitan areas. The adverse effects of pollution particles are most prominent in suscep...

  14. Effects of Ambient Air Pollution Exposure on Olfaction: A Review.

    PubMed

    Ajmani, Gaurav S; Suh, Helen H; Pinto, Jayant M

    2016-11-01

    Olfactory dysfunction affects millions of people worldwide. This sensory impairment is associated with neurodegenerative disease and significantly decreased quality of life. Exposure to airborne pollutants has been implicated in olfactory decline, likely due to the anatomic susceptibility of the olfactory nerve to the environment. Historically, studies have focused on occupational exposures, but more recent studies have considered effects from exposure to ambient air pollutants. To examine all relevant human data evaluating a link between ambient pollution exposure and olfaction and to review supporting animal data in order to examine potential mechanisms for pollution-associated olfactory loss. We identified and reviewed relevant articles from 1950 to 2015 using PubMed and Web of Science and focusing on human epidemiologic and pathophysiologic studies. Animal studies were included only to support pertinent data on humans. We reviewed findings from these studies evaluating a relationship between environmental pollutant exposure and olfactory function. We identified and reviewed 17 articles, with 1 additional article added from a bibliography search, for a total of 18 human studies. There is evidence in human epidemiologic and pathologic studies that increased exposure to ambient air pollutants is associated with olfactory dysfunction. However, most studies have used proxies for pollution exposure in small samples of convenience. Human pathologic studies, with supporting animal work, have also shown that air pollution can contact the olfactory epithelium, translocate to the olfactory bulb, and migrate to the olfactory cortex. Pollutants can deposit at each location, causing direct damage and disruption of tissue morphology or inducing local inflammation and cellular stress responses. Ambient air pollution may impact human olfactory function. Additional studies are needed to examine air pollution-related olfactory impacts on the general population using measured

  15. The use of non destructive biomarkers in the study of marine mammals.

    PubMed

    M Cristina Fossi And Letizia Marsili

    1997-01-01

    Marine mammals have been subject to heavy anthropogenic pressure by direct killing and chemical pollution all over the world. Most studies of contamination and biomarker responses in marine mammals have been conducted using animals killed by hunting out of a total of 12 cetacean species studied, 45 of the specimens were obtained by sacrificing the animal; out of a total of eight pinniped species studied, 40 of the specimens were obtained by killing. The development of a series of non destructive techniques to evaluate biomarker responses and residue levels is recommended for the hazard assessment and conservation of endangered species of marine mammals. Here we review the current status of the non destructive biomarker approach in marine mammals, describing the biological materials available for non destructive tests in stranded brain, liver, blood, skin, subcutaneous blubber, muscle and fur and free ranging animals blood, skin biopsy, fur and faeces and the respective biomarker techniques mixed function oxidase activity and DNA damage in skin biopsy samples; porphyrins in faeces and fur; esterases, porphyrins, clinical biochemical parameter, vitamin A and micronuclei in blood samples. Residue analysis can be carried out in the various biological materials. We also report the results of applying this methodological approach to cetaceans minke whale Balaenoptera acutorostrata, fin whale-- Balaenoptera physalus, beluga whale-- Delphinapterus leucas, short finned pilot whale-- Globicephala macrorhynchus, harbour porpoise -- Phocoena phocoena, Rissos dolphin-- Risso s Grampus griseus, Dall s porpoise-- Phocoenoides dalli dalli, melon headed whale-- Peponocephala electra, bottlenose dolphin -- Tursiops truncatus, striped dolphin-- Stenella coeruleoalba, spinner dolphin-- Stenella longirostris, killer whale-- Orcinus orca and pinnipeds northern fur seal- Callorhinus ursinus, hooded seal-- Cystophora cristata, grey seal-- Halichoerus grypus, harbour seal-- Phoca vitulina

  16. Monitoring human exposure to urban air pollutants

    SciTech Connect

    Barale, R.; Barrai, I.; Marrazzini, A.

    1993-10-01

    A multidisciplinary study on a general population exposed to vehicle exhaust was undertaken in Pisa in 1991. Environmental factors such as air pollution and those associated with lifestyle were studied. Meanwhile, biological and medical indicators of health condition were investigated. Chromosomal aberrations, sister chromatid exchanges (SCEs), and micronuclei in lymphocytes were included for the assessment of the genotoxic risk. Because of the large number (3800) of subjects being investigated, standardization of protocols was compulsory. The results on data reproducibility are reported. To assess the reliability of the protocol on a large scale, the population of Porto Tolle, a village located in northeast Italy, was studied and compared to a subset of the Pisa population. Preliminary results showed that probable differences between the two populations and individuals were present in terms of SCE frequencies. The study was potentially able to detect the effects of several factors such as age, smoking, genetics, and environment. The in vitro treatment of lymphocytes with diepoxybutane confirmed the presence of more responsive individuals and permitted us to investigate the genetic predisposition to genetic damage. The possible influence of environmental factors was studied by correlation analyses with external exposure to air pollutants as well as with several lifestyle factors. 10 refs., 5 figs., 1 tab.

  17. Oxidative Stress and Air Pollution Exposure

    PubMed Central

    Lodovici, Maura; Bigagli, Elisabetta

    2011-01-01

    Air pollution is associated with increased cardiovascular and pulmonary morbidity and mortality. The mechanisms of air pollution-induced health effects involve oxidative stress and inflammation. As a matter of fact, particulate matter (PM), especially fine (PM2.5, PM < 2.5 μm) and ultrafine (PM0.1, PM < 0.1 μm) particles, ozone, nitrogen oxides, and transition metals, are potent oxidants or able to generate reactive oxygen species (ROS). Oxidative stress can trigger redox-sensitive pathways that lead to different biological processes such as inflammation and cell death. However, it does appear that the susceptibility of target organ to oxidative injury also depends upon its ability to upregulate protective scavenging systems. As vehicular traffic is known to importantly contribute to PM exposure, its intensity and quality must be strongly relevant determinants of the qualitative characteristics of PM spread in the atmosphere. Change in the composition of this PM is likely to modify its health impact. PMID:21860622

  18. APPARATUS FOR NON-DESTRUCTIVE INSPECTION OF CANTILEVERED MEMBERS

    DOEpatents

    Taylor, E.R.; Mahoney, C.H.; Lay, C.R.

    1961-10-24

    An apparatus for non-destructive inspection of cantilevered members, such as compressor blades, is described. The member under inspection is vibrated with a regulated source of air under pressure. The amplitude of vibration of the member is maintained at its natural frequency. The frequency of vibration of the member is measured. An indication of an excessive decay or erratic shifting in the measured frequency above an allowable hysteretic decay is provided as an indication of a fault in the member. The member is vibrated for a selected test period. (AEC)

  19. Non-Destructive Inspection Methods for Propulsion Systems and Components

    DTIC Science & Technology

    1979-04-01

    Oftopulsion and Energetics Panel", et du "Consuiltant and Exchange Programm" d. 1’AGARD. RII* a pour but d’exarniner et do commenter l𔃾tat actual do l’art...Exchange Program" of AGARD. Its aim is to examine and comment on to-day’s state of the art, and the foreseeable or hoped progress of the non-destructive...should be recognised as such. These notes will therefore review and comment on the general problem, but emphaais will be on the application of minute

  20. MODELING POPULATION EXPOSURES TO OUTDOOR SOURCES OF HAZARDOUS AIR POLLUTANTS

    EPA Science Inventory

    Accurate assessment of human exposures is an important part of environmental health effects research. However, most air pollution epidemiology studies rely upon imperfect surrogates of personal exposures, such as information based on available central-site outdoor concentration ...

  1. Human exposure to pollutants in Poland

    SciTech Connect

    Wesolowski, J.J.; Jedrychowski, W.; Flak, E. )

    1992-07-01

    Serious environmental problems caused by decades of mismanagement of Poland's natural resources have been brought to light in recent years. All environmental media--air, water, food, and soil--have been burdened with toxic chemicals. Some environmental problems are so severe that the sources of pollution and the mitigation techniques needed are obvious, requiring no further research, but rather common sense, monies, and determination to implement the necessary controls and mitigation procedures. This paper will not address these obvious cases. Rather it will address that spectrum of environmental problems which requires a better understanding of public health risk in order to develop effective risk management strategies. Because these problems are numerous and monies limited, policy makers will need to set priorities both for research projects and control options. Using environmental concentration data presently available from Poland (especially for air), the paper will estimate human exposures, will point out research and monitoring needs, and hopefully, will lend credence to the concept that environmental policies and risk reduction strategies will be most effective if the Total Human Exposure Concept is used as the guiding scientific principle in risk assessment and management programs.

  2. CHARACTERIZATION OF INDOOR AND OUTDOOR AIR POLLUTION EXPOSURES AND SOURCES

    EPA Science Inventory

    Human exposures to indoor and outdoor pollutants vary depending on the sources and concentrations of pollutants as well as human behavioral factors that determine the extent of an individual's contact with indoor or outdoor pollutants. In general, the older populations spend more...

  3. Laser active thermography for non-destructive testing

    NASA Astrophysics Data System (ADS)

    Semerok, A.; Grisolia, C.; Fomichev, S. V.; Thro, P.-Y.

    2013-11-01

    Thermography methods have found their applications in different fields of human activity. The non-destructive feature of these methods along with the additional advantage by automated remote control and tests of nuclear installations without personnel attendance in the contaminated zone are of particular interest. Laser active pyrometry and laser lock-in thermography for in situ non-destructive characterization of micrometric layers on graphite substrates from European tokamaks were under extensive experimental and theoretical studies in CEA (France). The studies were aimed to obtain layer characterization with cross-checking the layer thermal contact coefficients determined by active laser pyrometry and lock-in thermography. The experimental installation comprised a Nd-YAG pulsed repetition rate laser (1 Hz - 10 kHz repetition rate frequency, homogeneous spot) and a home-made pyrometer system based on two pyrometers for the temperature measurements in 500 - 2600 K range. For both methods, the layer characterization was provided by the best fit of the experimental results and simulations. The layer thermal contact coefficients determined by both methods were quite comparable. Though there was no gain in the measurements accuracy, lock-in measurements have proved their advantage as being much more rapid. The obtained experimental and theoretical results are presented. Some practical applications and possible improvements of the methods are discussed.

  4. Local defect resonance for sensitive non-destructive testing

    NASA Astrophysics Data System (ADS)

    Adebahr, W.; Solodov, I.; Rahammer, M.; Gulnizkij, N.; Kreutzbruck, M.

    2016-02-01

    Ultrasonic wave-defect interaction is a background of ultrasound activated techniques for imaging and non-destructive testing (NDT) of materials and industrial components. The interaction, primarily, results in acoustic response of a defect which provides attenuation and scattering of ultrasound used as an indicator of defects in conventional ultrasonic NDT. The derivative ultrasonic-induced effects include e.g. nonlinear, thermal, acousto-optic, etc. responses also applied for NDT and defect imaging. These secondary effects are normally relatively inefficient so that the corresponding NDT techniques require an elevated acoustic power and stand out from conventional ultrasonic NDT counterparts for their specific instrumentation particularly adapted to high-power ultrasonic. In this paper, a consistent way to enhance ultrasonic, optical and thermal defect responses and thus to reduce an ultrasonic power required is suggested by using selective ultrasonic activation of defects based on the concept of local defect resonance (LDR). A strong increase in vibration amplitude at LDR enables to reliably detect and visualize the defect as soon as the driving ultrasonic frequency is matched to the LDR frequency. This also provides a high frequency selectivity of the LDR-based imaging, i.e. an opportunity of detecting a certain defect among a multitude of other defects in material. Some examples are shown how to use LDR in non-destructive testing techniques, like vibrometry, ultrasonic thermography and shearography in order to enhance the sensitivity of defect visualization.

  5. Non destructive testing of works of art by terahertz analysis

    NASA Astrophysics Data System (ADS)

    Bodnar, Jean-Luc; Metayer, Jean-Jacques; Mouhoubi, Kamel; Detalle, Vincent

    2013-11-01

    Improvements in technologies and the growing security needs in airport terminals lead to the development of non destructive testing devices using terahertz waves. Indeed, these waves have the advantage of being, on one hand, relatively penetrating. They also have the asset of not being ionizing. It is thus potentially an interesting contribution in the non destructive testing field. With the help of the VISIOM Company, the possibilities of this new industrial analysis method in assisting the restoration of works of art were then approached. The results obtained within this framework are presented here and compared with those obtained by infrared thermography. The results obtained show first that the THZ method, like the stimulated infrared thermography allows the detection of delamination located in murals paintings or in marquetries. They show then that the THZ method seems to allow detecting defects located relatively deeply (10 mm) and defects potentially concealed by other defects. It is an advantage compared to the stimulated infra-red thermography which does not make it possible to obtain these results. Furthermore, they show that the method does not seem sensitive to the various pigments constituting the pictorial layer, to the presence of a layer of "Japan paper" and to the presence of a layer of whitewash. It is not the case of the stimulated infrared thermography. It is another advantage of the THZ method. Finally, they show that the THZ method is limited in the detection of low-size defects. It is a disadvantage compared to the stimulated infrared thermography.

  6. Application of non-destructive techniques to assess the state of Hagia Sophia's mosaics

    NASA Astrophysics Data System (ADS)

    Moropoulou, Antonia; Karoglou, Maria; Labropoulos, Kyriakos C.; Delegou, Ekaterini T.; Katsiotis, Nikolaos K.; Karagiannis-Bakolas, Asterios

    2012-04-01

    The church of Hagia Sophia in Istanbul is a world heritage monument that epitomizes the byzantine ecclesiastic architecture. The church is decorated with mosaics from various historic periods. The preservation state of the mosaics is of high importance. In this study, non-destructive techniques (ground penetrating radar, infra-red thermography, fibreoptics microscopy) were employed on south upper gallery mosaic areas. The main aim of this on-site investigation was the evaluation of the preservation state of the mosaics and the previous interventions (materials characterization and decay diagnosis) in order to assess the performance of previous conservation/restoration interventions, as well as to verify the presence of mosaics in layers below the external plaster surfaces. Results indicated that is indeed possible to locate the grid of rendered mosaics. Regarding the preservation state of the mosaics, it was indicated that the main environmental decay factors were the high relative humidity levels with co-action of salt damp as well as the air pollutants. Moreover, it was revealed that previous incompatible restoration/conservation interventions have often accelerated the mosaics' degradation processes. Using non-destructive techniques it was possible to identify areas where the mosaic materials (tesserae and mortars) presented decay problems and in addition identify sub-layers that pose risk of detachment or decay intensification. In this way, NDT can contribute to the development of a strategic planning for mosaics conservation, protection and revealing.

  7. POPULATION-BASED EXPOSURE MODELING FOR AIR POLLUTANTS AT EPA'S NATIONAL EXPOSURE RESEARCH LABORATORY

    EPA Science Inventory

    The US EPA's National Exposure Research Laboratory (NERL) has been developing, applying, and evaluating population-based exposure models to improve our understanding of the variability in personal exposure to air pollutants. Estimates of population variability are needed for E...

  8. MODELING INHALATION AND MULTIMEDIA MULTIPATHWAY HUMAN EXPOSURES TO ENVIRONMENTAL POLLUTANTS

    EPA Science Inventory

    Estimation of exposures of children and adults to air toxics or multimedia pollutants require careful consideration of sources and concentrations of pollutants that may be present in different media, as well as various routes and pathways of exposures associated with age-specif...

  9. MODELING INHALATION AND MULTIMEDIA MULTIPATHWAY HUMAN EXPOSURES TO ENVIRONMENTAL POLLUTANTS

    EPA Science Inventory

    Estimation of exposures of children and adults to air toxics or multimedia pollutants require careful consideration of sources and concentrations of pollutants that may be present in different media, as well as various routes and pathways of exposures associated with age-specif...

  10. Evaluation and Application of Alternative Air Pollution Exposure Metrics in Air Pollution Epidemiology Studies

    EPA Science Inventory

    ABSTRACT: Periodic review, revision and subsequent implementation of the National Ambient Air Quality Standards for criteria air pollutants rely upon various types of scientific air quality, exposure, toxicological dose-response and epidemiological information. Exposure assessmen...

  11. Air pollution exposure prediction approaches used in air pollution epidemiology studies

    EPA Science Inventory

    Epidemiological studies of the health effects of air pollution have traditionally relied upon surrogates of personal exposures, most commonly ambient concentration measurements from central-site monitors. However, this approach may introduce exposure prediction errors and miscla...

  12. Air pollution exposure prediction approaches used in air pollution epidemiology studies

    EPA Science Inventory

    Epidemiological studies of the health effects of air pollution have traditionally relied upon surrogates of personal exposures, most commonly ambient concentration measurements from central-site monitors. However, this approach may introduce exposure prediction errors and miscla...

  13. Evaluation and Application of Alternative Air Pollution Exposure Metrics in Air Pollution Epidemiology Studies

    EPA Science Inventory

    ABSTRACT: Periodic review, revision and subsequent implementation of the National Ambient Air Quality Standards for criteria air pollutants rely upon various types of scientific air quality, exposure, toxicological dose-response and epidemiological information. Exposure assessmen...

  14. Non-destructive shadowgraph imaging of ultra-cold atoms.

    PubMed

    Wigley, P B; Everitt, P J; Hardman, K S; Hush, M R; Wei, C H; Sooriyabandara, M A; Manju, P; Close, J D; Robins, N P; Kuhn, C C N

    2016-10-15

    An imaging system is presented that is capable of far-detuned non-destructive imaging of a Bose-Einstein condensate with the signal proportional to the second spatial derivative of the density. Whilst demonstrated with application to Rb85, the technique generalizes to other atomic species and is shown to be capable of a signal-to-noise of ∼25 at 1 GHz detuning with 100 in-trap images showing no observable heating or atom loss. The technique is also applied to the observation of individual trajectories of stochastic dynamics inaccessible to single shot imaging. Coupled with a fast optical phase locked loop, the system is capable of dynamically switching to resonant absorption imaging during the experiment.

  15. Non-destructive shadowgraph imaging of ultra-cold atoms

    NASA Astrophysics Data System (ADS)

    Wigley, P. B.; Everitt, P. J.; Hardman, K. S.; Hush, M. R.; Wei, C. H.; Sooriyabandara, M. A.; Manju, P.; Close, J. D.; Robins, N. P.; Kuhn, C. C. N.

    2016-10-01

    An imaging system is presented that is capable of far-detuned non-destructive imaging of a Bose-Einstein condensate with the signal proportional to the second spatial derivative of the density. Whilst demonstrated with application to $^{85}\\text{Rb}$, the technique generalizes to other atomic species and is shown to be capable of a signal to noise of ${\\sim}25$ at $1$GHz detuning with $100$ in-trap images showing no observable heating or atom loss. The technique is also applied to the observation of individual trajectories of stochastic dynamics inaccessible to single shot imaging. Coupled with a fast optical phase lock loop, the system is capable of dynamically switching to resonant absorption imaging during the experiment.

  16. Non-destructive photoacoustic imaging of metal surface defects

    NASA Astrophysics Data System (ADS)

    Jeon, Seungwan; Kim, Jeesu; Yun, Jong Pil; Kim, Chulhong

    2016-11-01

    The detection of metal surface defects is important in achieving the goals of product quality enhancement and manufacturing cost reduction. Identifying the defects with visual inspection is difficult, inaccurate, and time-consuming. Thus, several inspection methods using line cameras, magnetic field, and ultrasound have been proposed. However, identifying small defects on metal surfaces remains a challenge. To deal with this problem, we propose the use of photoacoustic imaging (PAI) as a new non-destructive imaging tool to detect metal surface defects. We successfully visualized two types of cracks (i.e., unclassified and seam cracks) in metal plate samples using PAI. In addition, we successfully extracted cracked edges from height-encoded photoacoustic maximum amplitude projection images using the Laplacian of Gaussian filtering method, and then, quantified the detected edges for a statistical analysis. We concluded that PAI can be useful in detecting metal surface defects reducing the defect rate and manufacturing cost during metal production.

  17. Non-destructive evaluation method employing dielectric electrostatic ultrasonic transducers

    NASA Technical Reports Server (NTRS)

    Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

    2003-01-01

    An acoustic nonlinearity parameter (.beta.) measurement method and system for Non-Destructive Evaluation (NDE) of materials and structural members novelly employs a loosely mounted dielectric electrostatic ultrasonic transducer (DEUT) to receive and convert ultrasonic energy into an electrical signal which can be analyzed to determine the .beta. of the test material. The dielectric material is ferroelectric with a high dielectric constant .di-elect cons.. A computer-controlled measurement system coupled to the DEUT contains an excitation signal generator section and a measurement and analysis section. As a result, the DEUT measures the absolute particle displacement amplitudes in test material, leading to derivation of the nonlinearity parameter (.beta.) without the costly, low field reliability methods of the prior art.

  18. Non-destructive evaluation of water ingress in photovoltaic modules

    DOEpatents

    Bora, Mihail; Kotovsky, Jack

    2017-03-07

    Systems and techniques for non-destructive evaluation of water ingress in photovoltaic modules include and/or are configured to illuminate a photovoltaic module comprising a photovoltaic cell and an encapsulant with at least one beam of light having a wavelength in a range from about 1400 nm to about 2700 nm; capture one or more images of the illuminated photovoltaic module, each image relating to a water content of the photovoltaic module; and determine a water content of the photovoltaic module based on the one or more images. Systems preferably include one or more of a light source, a moving mirror, a focusing lens, a beam splitter, a stationary mirror, an objective lens and an imaging module.

  19. Non-Destructive Classification Approaches for Equilbrated Ordinary Chondrites

    NASA Technical Reports Server (NTRS)

    Righter, K.; Harrington, R.; Schroeder, C.; Morris, R. V.

    2013-01-01

    Classification of meteorites is most effectively carried out by petrographic and mineralogic studies of thin sections, but a rapid and accurate classification technique for the many samples collected in dense collection areas (hot and cold deserts) is of great interest. Oil immersion techniques have been used to classify a large proportion of the US Antarctic meteorite collections since the mid-1980s [1]. This approach has allowed rapid characterization of thousands of samples over time, but nonetheless utilizes a piece of the sample that has been ground to grains or a powder. In order to compare a few non-destructive techniques with the standard approaches, we have characterized a group of chondrites from the Larkman Nunatak region using magnetic susceptibility and Moessbauer spectroscopy.

  20. Non-destructive monitoring of river embankments using GPR

    NASA Astrophysics Data System (ADS)

    di Prinzio, Monica; Bittelli, Marco; Castellarin, Attilio; Rossi Pisa, Paola

    2010-05-01

    Non-destructive investigations and controls of civil structures are improving day by day, however the scientific literature reports only a few documented cases of Ground Penetrating Radar (GPR) applications to the detection of voids and discontinuities in hydraulic defense structures such as river embankments and levee systems. GPR can assist decision making in a number of fields by enhancing our knowledge of subsurface features. We applied successfully GPR to the monitoring of river levees for the detectioning of animal burrows in river levees, which may trigger levee failures by piping. The manageability and the non-invasivity of GPR have resulted to be particularly suitable for this application. First because GPR is an extensive investigation method that enables one to rapidly cover a wide area, locating voids that are difficult and costly to locate using other intrusive methods. Second, GPR returns detailed information about the possible presence of voids and discontinuities within river embankments.

  1. Non-destructive Faraday imaging of dynamically controlled ultracold atoms

    SciTech Connect

    Gajdacz, Miroslav; Pedersen, Poul L.; Mørch, Troels; Hilliard, Andrew J.; Arlt, Jan; Sherson, Jacob F.

    2013-08-15

    We describe an easily implementable method for non-destructive measurements of ultracold atomic clouds based on dark field imaging of spatially resolved Faraday rotation. The signal-to-noise ratio is analyzed theoretically and, in the absence of experimental imperfections, the sensitivity limit is found to be identical to other conventional dispersive imaging techniques. The dependence on laser detuning, atomic density, and temperature is characterized in a detailed comparison with theory. Due to low destructiveness, spatially resolved images of the same cloud can be acquired up to 2000 times. The technique is applied to avoid the effect of shot-to-shot fluctuations in atom number calibration, to demonstrate single-run vector magnetic field imaging and single-run spatial imaging of the system's dynamic behavior. This demonstrates that the method is a useful tool for the characterization of static and dynamically changing properties of ultracold atomic clouds.

  2. Non-destructive diffraction enhanced imaging of seeds.

    PubMed

    Young, Lester W; Parham, Christopher; Zhong, Zhong; Chapman, Dean; Reaney, Martin J T

    2007-01-01

    Techniques that make possible the non-destructive continuous observation of plant anatomy and developmental processes provide novel insights into these phenomena. Non-destructive imaging of seeds was demonstrated using the synchrotron-based X-ray imaging technique, diffraction enhanced imaging (DEI). The seed images obtained had good contrast and definition, allowing anatomical structures and physiological events to be observed. Structures such as hypocotyl-root axes, cotyledons, seed coats, air cavities, and embryo-less Brassica napus L. seeds were readily observed using DEI. Embryo axes, scutella, pericarp furrows, coleoptiles, and roots were observable over a time-course in individual germinating Triticum aestivum L. caryopses. Novel anatomical and physiological observations were also made that would have been difficult to make continuously using other techniques. The physical principles behind DEI make it a unique imaging technique. Contrast in DEI is the result of X-ray refraction at the density differences occurring at tissue boundaries, scatter caused by regions containing ordered molecules such as cellulose fibres, and attenuation. Sectioning of samples and the infusion of stains or other contrast agents are not necessary. Furthermore, as high-energy X-rays are used (30-40 keV), little X-ray absorption occurs, resulting in low levels of radiation damage. Consequently, studies of developmental processes may be performed on individuals. Individual germinating B. napus and T. aestivum seeds were imaged at several time points without incurring any apparent radiation damage. DEI offers a unique way of examining plant anatomy, development, and physiology, and provides images that are complementary to those obtained through other techniques.

  3. Reducing indoor residential exposures to outdoor pollutants

    SciTech Connect

    Sherman, Max H.; Matson, Nance E.

    2003-07-01

    The basic strategy for providing indoor air quality in residences is to dilute indoor sources with outdoor air. This strategy assumes that the outdoor air does not have pollutants at harmful levels or that the outdoor air is, at least, less polluted than the indoor air. When this is not the case, different strategies need to be employed to ensure adequate air quality in the indoor environment. These strategies include ventilation systems, filtration and other measures. These strategies can be used for several types of outdoor pollution, including smog, particulates and toxic air pollutants. This report reviews the impacts that typical outdoor air pollutants can have on the indoor environment and provides design and operational guidance for mitigating them. Poor quality air cannot be used for diluting indoor contaminants, but more generally it can become an indoor contaminant itself. This paper discusses strategies that use the building as protection against potentially hazardous outdoor pollutants, including widespread pollutants, accidental events, and potential attacks.

  4. Usage of FTIR-ATR as Non-Destructive Analysis of Selected Toxic Dyes

    NASA Astrophysics Data System (ADS)

    Bartošová, Alica; Blinová, Lenka; Sirotiak, Maroš; Michalíková, Anna

    2017-06-01

    The degradation of the environment which is due to the discharge of polluting wastewater from industrial sources poses a real problem in several countries. Textile industries use large volumes of water in their operations, discharging thus large volume of wastewater into the environment, most of which is untreated. The wastewater contains a variety of chemicals from various stages of process operations, including desizing, scouring, bleaching and dyeing. The main purpose of this paper is to introduce Infrared Spectrometry with Fourier transformation as a non-destructive method for study, identifation and rapid determination of selected representatives of cationic (Methylene Blue), azo (Congo Red, Eriochrome Black T) and nitroso (Naphthol Green B) dyes. In conjunction with the ATR technique, FTIR offers a reliable detection method of dyes without extraction by other dangerous substances. Spectral interpretation of dye spectra revealed valuable information about the identification and characterization of each group of dyes.

  5. Effects of Ambient Air Pollution Exposure on Olfaction: A Review

    PubMed Central

    Ajmani, Gaurav S.; Suh, Helen H.; Pinto, Jayant M.

    2016-01-01

    Background: Olfactory dysfunction affects millions of people worldwide. This sensory impairment is associated with neurodegenerative disease and significantly decreased quality of life. Exposure to airborne pollutants has been implicated in olfactory decline, likely due to the anatomic susceptibility of the olfactory nerve to the environment. Historically, studies have focused on occupational exposures, but more recent studies have considered effects from exposure to ambient air pollutants. Objectives: To examine all relevant human data evaluating a link between ambient pollution exposure and olfaction and to review supporting animal data in order to examine potential mechanisms for pollution-associated olfactory loss. Methods: We identified and reviewed relevant articles from 1950 to 2015 using PubMed and Web of Science and focusing on human epidemiologic and pathophysiologic studies. Animal studies were included only to support pertinent data on humans. We reviewed findings from these studies evaluating a relationship between environmental pollutant exposure and olfactory function. Results: We identified and reviewed 17 articles, with 1 additional article added from a bibliography search, for a total of 18 human studies. There is evidence in human epidemiologic and pathologic studies that increased exposure to ambient air pollutants is associated with olfactory dysfunction. However, most studies have used proxies for pollution exposure in small samples of convenience. Human pathologic studies, with supporting animal work, have also shown that air pollution can contact the olfactory epithelium, translocate to the olfactory bulb, and migrate to the olfactory cortex. Pollutants can deposit at each location, causing direct damage and disruption of tissue morphology or inducing local inflammation and cellular stress responses. Conclusions: Ambient air pollution may impact human olfactory function. Additional studies are needed to examine air pollution

  6. Air Pollution Exposure Modeling for Health Studies | Science ...

    EPA Pesticide Factsheets

    Dr. Michael Breen is leading the development of air pollution exposure models, integrated with novel personal sensor technologies, to improve exposure and risk assessments for individuals in health studies. He is co-investigator for multiple health studies assessing the exposure and effects of air pollutants. These health studies include participants with asthma, diabetes, and coronary artery disease living in various U.S. cities. He has developed, evaluated, and applied novel exposure modeling and time-activity tools, which includes the Exposure Model for Individuals (EMI), GPS-based Microenvironment Tracker (MicroTrac) and Exposure Tracker models. At this seminar, Dr. Breen will present the development and application of these models to predict individual-level personal exposures to particulate matter (PM) for two health studies in central North Carolina. These health studies examine the association between PM and adverse health outcomes for susceptible individuals. During Dr. Breen’s visit, he will also have the opportunity to establish additional collaborations with researchers at Harvard University that may benefit from the use of exposure models for cohort health studies. These research projects that link air pollution exposure with adverse health outcomes benefit EPA by developing model-predicted exposure-dose metrics for individuals in health studies to improve the understanding of exposure-response behavior of air pollutants, and to reduce participant

  7. Air Pollution Exposure Model for Individuals (EMI) in Health Studies

    EPA Science Inventory

    In health studies, traffic-related air pollution is associated with adverse respiratory effects. Due to cost and participant burden of personal measurements, health studies often estimate exposures using local ambient air monitors. Since outdoor levels do not necessarily reflect ...

  8. Air Pollution Exposure Model for Individuals (EMI) in Health Studies

    EPA Science Inventory

    In health studies, traffic-related air pollution is associated with adverse respiratory effects. Due to cost and participant burden of personal measurements, health studies often estimate exposures using local ambient air monitors. Since outdoor levels do not necessarily reflect ...

  9. Novel Approaches for Estimating Human Exposure to Air Pollutants

    EPA Science Inventory

    Numerous health studies have used measurements from a few central-site ambient monitors to characterize air pollution exposures. Relying on solely on central-site ambient monitors does not account for the spatial-heterogeneity of ambient air pollution patterns, the temporal varia...

  10. Novel Approaches for Estimating Human Exposure to Air Pollutants

    EPA Science Inventory

    Numerous health studies have used measurements from a few central-site ambient monitors to characterize air pollution exposures. Relying on solely on central-site ambient monitors does not account for the spatial-heterogeneity of ambient air pollution patterns, the temporal varia...

  11. Air pollution exposure prediction approaches used in air pollution epidemiology studies.

    PubMed

    Özkaynak, Halûk; Baxter, Lisa K; Dionisio, Kathie L; Burke, Janet

    2013-01-01

    Epidemiological studies of the health effects of outdoor air pollution have traditionally relied upon surrogates of personal exposures, most commonly ambient concentration measurements from central-site monitors. However, this approach may introduce exposure prediction errors and misclassification of exposures for pollutants that are spatially heterogeneous, such as those associated with traffic emissions (e.g., carbon monoxide, elemental carbon, nitrogen oxides, and particulate matter). We review alternative air quality and human exposure metrics applied in recent air pollution health effect studies discussed during the International Society of Exposure Science 2011 conference in Baltimore, MD. Symposium presenters considered various alternative exposure metrics, including: central site or interpolated monitoring data, regional pollution levels predicted using the national scale Community Multiscale Air Quality model or from measurements combined with local-scale (AERMOD) air quality models, hybrid models that include satellite data, statistically blended modeling and measurement data, concentrations adjusted by home infiltration rates, and population-based human exposure model (Stochastic Human Exposure and Dose Simulation, and Air Pollutants Exposure models) predictions. These alternative exposure metrics were applied in epidemiological applications to health outcomes, including daily mortality and respiratory hospital admissions, daily hospital emergency department visits, daily myocardial infarctions, and daily adverse birth outcomes. This paper summarizes the research projects presented during the symposium, with full details of the work presented in individual papers in this journal issue.

  12. Contamination of Outer Surfaces of International Space Station Studied by Non-Destructive Techniques

    NASA Astrophysics Data System (ADS)

    Borisov, V. A.; Naumov, S. F.; Sokolova, S. P.; Kurilenok, A. O.; Skurat, V. E.; Zhigach, A. N.; Beriozkina, N. G.; Leipunsky, I. O.; Pshechenkov, P. A.; Zotova, E. S.; Volkov, I. O.; Naumkin, A. V.; Artemov, V. V.

    The aim of this work is to study non -volatile components of contamination deposits on outer surfaces of International Space Station (Russian segment) by a complex of non-destructive techniques - X-ray photoelectron spectroscopy (XPS), diffuse reflection infrared spectroscopy, scanning electron microscopy and local X-ray microanalysis (LXMA). These methods were used for investigation of 40 samples of materials and coatings after their exposure to residual atmosphere of Earth and external conditions of spacecraft. Elemental and chemical composition of surface and sub-surface layers is varied in very broad limits due to concurrence of many processes changing the sample composition. Contamination deposits contain nitrogenous components besides ubiquitous carbonaceous and siliceous components that are typical for spacecraft surface contamination.

  13. A Novel Application of Non-Destructive Readout Technology to Localisation Microscopy

    PubMed Central

    Barnett, Samuel F. H.; Snape, Mary; Hunter, C. Neil; Juárez, Miguel A.; Cadby, Ashley J.

    2017-01-01

    The fitting precision in localisation microscopy is highly dependent on the signal to noise ratio. To increase the quality of the image it is therefore important to increase the signal to noise ratio of the measurements. We present an imaging system for localisation microscopy based on non-destructive readout camera technology that can increase the signal to noise ratio of localisation based microscopy. This approach allows for much higher frame rates through subsampling a traditional camera frame. By matching the effective exposure to both the start time and duration of a single molecule we diminish the effects of read noise and temporal noise. We demonstrate the application of this novel method to localisation microscopy and show both an increase in the attainable signal to noise ratio of data collection and an increase in the number of detected events. PMID:28195127

  14. A Novel Application of Non-Destructive Readout Technology to Localisation Microscopy

    NASA Astrophysics Data System (ADS)

    Barnett, Samuel F. H.; Snape, Mary; Hunter, C. Neil; Juárez, Miguel A.; Cadby, Ashley J.

    2017-02-01

    The fitting precision in localisation microscopy is highly dependent on the signal to noise ratio. To increase the quality of the image it is therefore important to increase the signal to noise ratio of the measurements. We present an imaging system for localisation microscopy based on non-destructive readout camera technology that can increase the signal to noise ratio of localisation based microscopy. This approach allows for much higher frame rates through subsampling a traditional camera frame. By matching the effective exposure to both the start time and duration of a single molecule we diminish the effects of read noise and temporal noise. We demonstrate the application of this novel method to localisation microscopy and show both an increase in the attainable signal to noise ratio of data collection and an increase in the number of detected events.

  15. Non-destructive monitoring of curing process in precast concrete

    NASA Astrophysics Data System (ADS)

    Aparicio, S.; Ranz, J.; Fernández, R.; Albert, V.; Fuente, J. V.; Hernández, M. G.

    2012-12-01

    Currently, the use of precast concrete elements has gained importance because it offers many advantages over site-cast concrete. A disadvantage of site-cast concrete is that its properties vary according to the manufacturing method, the environment and even the operator who carried out the mixing, pouring and implementation of the concrete. Precast concrete elements are manufactured in a controlled environment (typically referred to as a precast plant) and this reduces the shrinkage and creep. One of the key properties of precast concrete is the capability to gain compressive strength rapidly under the appropriate conditions. The compressive strength determines if the precast can be stripped from the form or manipulated. This parameter is measured using destructive testing over cylindrical or cubic samples. The quality control of precast is derived from the fracture suffered by these elements, resulting in a "pass or fail" evaluation. In most cases, the solution to this problem is to allow the material to cure for a few hours until it acquires sufficient strength to handle the precast element. The focus of this paper is the description of the research project "CUREND". This project aims to design a non-destructive methodology to monitor the curing process in precast concrete. The monitoring will be performed using wireless sensor networks.

  16. Method of non-destructively inspecting a curved wall portion

    DOEpatents

    Fong, James T.

    1996-01-01

    A method of non-destructively inspecting a curved wall portion of a large and thick walled vessel for a defect by computed tomography is provided. A collimated source of radiation is placed adjacent one side of the wall portion and an array of detectors for the radiation is placed on the other side adjacent the source. The radiation from the source passing through the wall portion is then detected with the detectors over a limited angle, dependent upon the curvature of the wall of the vessel, to obtain a dataset. The source and array are then coordinately moved relative to the wall portion in steps and a further dataset is obtained at each step. The plurality of datasets obtained over the limited angle is then processed to produce a tomogram of the wall portion to determine the presence of a defect therein. In a preferred embodiment, the curved wall portion has a center of curvature so that the source and the array are positioned at each step along a respective arc curved about the center. If desired, the detector array and source can be reoriented relative to a new wall portion and an inspection of the new wall portion can be easily obtained. Further, the source and detector array can be indexed in a direction perpendicular to a plane including the limited angle in a plurality of steps so that by repeating the detecting and moving steps at each index step, a three dimensional image can be created of the wall portion.

  17. Non-destructive evaluation of mechanical properties of magnetic materials

    SciTech Connect

    Kankolenski, K.P.; Hua, S.Z.; Yang, D.X.; Hicho, G.E.; Swartzendruber, L.J.; Zang, Z.; Chopra, H.D.

    2000-07-01

    A magnetic-based non-destructive evaluation (NDE) method, which employs Barkhausen effect and measurement of the hysteresis loops, is used to correlate the magnetic and mechanical properties of ultra low carbon (ULC) steel. In particular, the NDE method was used to detect small deviations from linearity that occur in the stress-strain curve well below the 0.2% offset strain, and which generally defines the yield point in materials. Results show that three parameters: jumpsum and jumpsum rate (derived from the Barkhausen spectrum), and the relative permeability (derived from the B-H loops) varies sensitively with small permanent strains, and can be related to the plastic deformation in ULC steels. Investigation of micromagnetic structure revealed that plastic deformation leaves a residual stress state in the samples; the associated magneto-elastic energy makes the favorable easy axis of magnetization in a given grain to be the one that lies closest to the tensile axis. The consequence of this realignment of domains is that wall motion becomes intergranular in nature (as opposed to intragranular in unstrained samples). As a result, the more complex grain boundaries instead of dislocations, become the dominant pinning sites for domain walls. These observations provide a microscopic interpretation of the observed changes in the measured magnetic properties.

  18. A non-destructive method for dating human remains

    USGS Publications Warehouse

    Lail, Warren K.; Sammeth, David; Mahan, Shannon; Nevins, Jason

    2013-01-01

    The skeletal remains of several Native Americans were recovered in an eroded state from a creek bank in northeastern New Mexico. Subsequently stored in a nearby museum, the remains became lost for almost 36 years. In a recent effort to repatriate the remains, it was necessary to fit them into a cultural chronology in order to determine the appropriate tribe(s) for consultation pursuant to the Native American Grave Protection and Repatriation Act (NAGPRA). Because the remains were found in an eroded context with no artifacts or funerary objects, their age was unknown. Having been asked to avoid destructive dating methods such as radiocarbon dating, the authors used Optically Stimulated Luminescence (OSL) to date the sediments embedded in the cranium. The OSL analyses yielded reliable dates between A.D. 1415 and A.D. 1495. Accordingly, we conclude that the remains were interred somewhat earlier than A.D. 1415, but no later than A.D. 1495. We believe the remains are from individuals ancestral to the Ute Mouache Band, which is now being contacted for repatriation efforts. Not only do our methods contribute to the immediate repatriation efforts, they provide archaeologists with a versatile, non-destructive, numerical dating method that can be used in many burial contexts.

  19. Non-destructive characterization of archaeological glasses by neutron tomography

    NASA Astrophysics Data System (ADS)

    Fiori, F.; Giunta, G.; Hilger, A.; Kardjilov, N.; Rustichelli, F.

    2006-11-01

    The present work is carried out in the framework of a National Italian Project, whose aim is the assessment of innovative physical non-destructive techniques applied to archaeology. Towards this end, some archaeological artefacts have been studied by our group, in collaboration with the National Museum of Altino (VE) and EniTecnologie S.p.A. The objects come from the excavations in Altino, near Venice, where at least three different historical layers are present, corresponding to ages starting from approximately VII century B.C. In particular, in this work the results of neutron tomography investigations on three I-II century A.D. glass fragments are reported. The experiments were performed at the cold neutron radiography facility CONRAD at HMI (Berlin). For the 3D tomographical reconstruction of the sample, 200 projections were collected while the sample was rotated around a defined axis. The rotation interval was 180 degrees. The results show that the technique is able to reconstruct well the structural features of the investigated objects such as, in particular, highly absorbing zones and the presence of defects in the bulk.

  20. FIRST 100 T NON-DESTRUCTIVE MAGNET OUTER COIL SET

    SciTech Connect

    J. BACON; A. BACA; ET AL

    1999-09-01

    The controlled power outer coil set of the first 100 T non-destructive (100 T ND) magnet is described. This magnet will be installed as part of the user facility research equipment at the National High Magnetic Field laboratory (NHMFL) Pulsed Field Facility at Los Alamos National Laboratory. The 100 T ND controlled power outer coil set consists of seven nested, mechanically independent externally reinforced coils. These coils, in combination, will produce a 47 T platform field in a 225-mm diameter bore. Using inertial energy storage a synchronous motor/generator provides ac power to a set of seven ac-dc converters rated at 64 MW/80 MVA each. These converters energize three independent coil circuits to create 170 MJ of field energy in the outer coil set at the platform field of 47 T. Each coil consists of a multi-layer winding of high strength conductor supported by an external high strength stainless steel shell. Coils with the highest magnetic loads will utilize a reinforcing shell fabricated from highly cold worked 301 stainless steel strip. The autofrettage conditioning method will be used to pre-stress the coils and thereby limit conductor and reinforcement strains to the elastic range. The purpose of pre-stressing the coils is to attain a design life of 10,000 full field pulses. The operation and conditioning of the coil set will be described along with special features of its design, magnetic and structural analyses and construction.

  1. Non-destructive testing of the MEGAPIE target

    NASA Astrophysics Data System (ADS)

    Dai, Y.; Wohlmuther, M.; Boutellier, V.; Hahl, S.; Lagotzki, A.; Leu, H.; Linder, H. P.; Schwarz, R.; Spahr, A.; Zanini, L.; Kuster, D.; Gavillet, D.; Wagner, W.

    2016-01-01

    Non-destructive testing (NDT) is one important part of the post-irradiation examination (PIE) of the MEGAPIE target. It includes visual inspection and ultrasonic measurement of the beam window of the T91 LBE container and gamma mapping of the beam window of the AlMg3 safety-container. The visual inspection showed no visible failure in the proton beam window area of the T91 LBE container. The ultrasonic measurement demonstrated no detectable change in the wall thickness of the T91 beam window, which implies no severe corrosion effect induced by flowing LBE during the four-month irradiation period. The gamma mapping provided the distribution of 22Na, a spallation product, in the proton beam window area of the AlMg3 safety-container. The result was used to evaluate the accumulated proton fluence distribution profile, the input data for determining irradiation parameters. A maximum proton fluence of 1.9 × 1025 p/m2 was deduced. The corresponding displacement damage degree in the T91 beam window was 7.1 dpa.

  2. Non-destructive investigation of thermoplastic reinforced composites

    SciTech Connect

    Hassen, Ahmed; Taheri, Hossein; Vaidya, Uday

    2016-05-09

    This paper studies various manufacturing defects in glass fiber/Polypropylene (PP) composite parts and their methods of detection. Foreign Object Inclusion (FOI) of different shapes, sizes, and materials were placed in a glass fiber/PP panel made by compression molding. The paper aims to characterize the fiber orientation and fiber related defects such as fiber waviness in the composite specimen. Comprehensive investigation for different Non Destructive Evaluation (NDE) techniques, namely X-ray radiography and Ultrasonic Testing (UT) techniques to trace and characterize the embedded defects and the composite texture are presented. Conventional X-ray radiography successfully identified the fiber orientation in two dimension (2-D) plane; however, information for the sample depth was not captured. The radiography techniques showed low relative errors for the defect size measurements (maximum error was below 9.5%) when compared to the ultrasonic techniques. Ultrasonic techniques were able to map all the embedded artificial defects. Phase Array (PA) ultrasonic technique was able to precisely locate the FOI in the glass fiber/PP specimen. Nerveless, the shape and size of the defects were not accurately determined due to the high signal attenuation and distortion characteristics of the E-glass fiber.

  3. Non-Destructive Evaluation (NDE) Applications of THz Radiation

    NASA Astrophysics Data System (ADS)

    Zimdars, David

    2005-03-01

    The technology and applications of time domain terahertz (THz) imaging to non-destructive evaluation (NDE) will be discussed. THz imaging has shown great promise in 2 and 3 dimensional non-contact inspection of non-conductive materials such as plastics, foam, composites, ceramics, paper, wood and glass. THz imaging employs safe low power non-ionizing electromagnetic pulses, with lateral resolution < 200 um, and depth resolution < 50 um. THz pulses can be analyzed spectroscopically to reveal chemical content. Recently, highly integrated turn-key THz imaging systems have been introduced commercially. We will demonstrate the detection of voids and disbonds intentionally incorporated within the sprayed on foam insulation of a space shuttle external tank mock-up segments. An industrially hardened THz scanning system which has been deployed to scan the space shuttle tank with small remote transceiver will be described. Additional terahertz security imaging applications for the detection of weapons and explosives will also be discussed, as well as the application of terahertz sensors for high speed industrial process monitoring and quality control.

  4. Non-destructive sub-THz CW imaging

    NASA Astrophysics Data System (ADS)

    Karpowicz, Nicholas; Zhong, Hua; Xu, Jingzhou; Lin, Kuang-I.; Hwang, Jenn-Shyong; Zhang, Xi-Cheng

    2005-03-01

    A simple, compact CW sub-THz imaging system, utilizing a 0.2 and 0.6 THz Gunn diode source is presented. A silicon beam lead diode detector and a Golay cell are used for the detection. Various results are presented, which show that the CW THz imaging modality is suitable for diverse applications, such as non-destructive testing and security. The key components of the system include the Gunn diode assembly, an optical chopper, a polyethylene lens, a detector, a lock-in amplifier, and two translation stages. The beam from the Gunn diode is focused on the sample being imaged by the polyethylene lens, the transmitted or reflected beam is measured by the detector. The energy transmitted through the sample at each point in the plane of the sample is detected. Since the system has relatively few components compared to pulsed THz imaging systems, it is less expensive and easier to design and operate, although it does not provide depth or spectral information about the sample. Since no time-delay scans take place, scanning can be done quickly compared to a time-domain system, limited by the maximum velocity of the translation stages and response of the detectors. It provides information about the macroscopic features of hidden structures within materials that are transparent to sub THz radiation, such as space shuttle insulating foam, articles of clothing, and luggage.

  5. Non-destructive acoustic defect detection in drug tablets.

    PubMed

    Akseli, Ilgaz; Mani, Girindra N; Cetinkaya, Cetin

    2008-08-06

    For physical defect detection in drug tablets, a non-destructive and non-contact technique based on air coupled excitation and interferometric detection is presented. Physical properties and mechanical integrity of drug tablets can often affect their therapeutic and structural functions. The monitoring for defects and the characterization of tablet mechanical properties therefore have been of practical interest for solid oral dosage forms. The presented monitoring approach is based on the analysis of the transient vibrational responses of an acoustically excited tablet in both in temporal and spectral domains. The pulsed acoustic field exciting the tablet is generated by an air-coupled transducer. Using a laser vibrometer, the out-of-plane vibrational transient response of the tablet is detected and acquired in a non-contact manner. The physical state of the tablet is evaluated based on the spectral properties of these transient responses. In the current study, the effectiveness of three types of simple similarity measures is evaluated for their potential uses as defect detection norms, and for their potential use in quantifying the extent of tablet defect is discussed. It is found that these quantities can not only be used for identification of defective tablets, but could also provide a measure for the extent of the damage.

  6. Non-destructive compositional analysis of historic organ reed pipes

    NASA Astrophysics Data System (ADS)

    Manescu, A.; Fiori, F.; Giuliani, A.; Kardjilov, N.; Kasztovszky, Z.; Rustichelli, F.; Straumal, B.

    2008-03-01

    In order to be able to reproduce historic organ reed pipes, a bulk non-destructive chemical composition analysis was performed on the tongues and shallots, focusing mainly on the ratio between copper and zinc and on the presence of lead. Prompt gamma activation analysis results allowed us to observe for the first time that the ratio between the two main components of the brass alloy changed from Cu:Zn = 3:1 for the old tongues and shallots to Cu:Zn = 2:1 around the middle of the 18th century, which is typical also for the modern alloys offered to the organ builders nowadays. We also discovered that the Pb content in the old historic brass alloy diminished until the middle of 18th century when the brass alloy became mainly Pb free. The non-uniform lead distribution inside one of the shallots obtained from a prompt gamma activation analysis (PGAA) experiment was studied by neutron tomography. It gave us a three-dimensonal (3D) distribution of the lead inclusions inside the shallots. The lead particles are concentrated towards the base of the shallot.

  7. Non-Destructive Assay of Curium Contaminated Transuranic Waste Drums

    SciTech Connect

    Foster, L.A.

    1998-11-01

    At the Plutonium Facility at Los Alamos National Laboratory, a series of non-destructive assays were performed on five transuranic waste (TRU) drums containing non-plutonium scrap metal that was potentially contaminated with weapons grade plutonium and trace quantities of curium. Typically, waste drums containing metal matrices are assayed for plutonium content using passive neutron coincidence counting techniques. The presence of trace quantities of Cm-244 prevents this type of analysis because of the strong coincidence signal created by spontaneous fission of Cm-244. To discriminate between the plutonium and curium materials present, an active neutron measurement technique was used. A Cf shuffler designed for measurement of uranium bearing materials was calibrated for plutonium in the active mode. The waste drums were then assayed for plutonium content in the shuffler using the active-mode calibration. The curium contamination levels were estimated from the difference between the active-mode measurement in the shuffler and a passive assay in a neutron coincidence counter. Far field gamma-ray measurements were made to identify additional radioactive contaminants and to corroborate the plutonium measurement results obtained from the active-mode assay. This report describes in detail the measurement process used for characterization of these waste drums. The measurement results and the estimated uncertainty will be presented.

  8. Non-destructive investigation of thermoplastic reinforced composites

    SciTech Connect

    Hassen, Ahmed; Taheri, Hossein; Vaidya, Uday

    2016-05-09

    This paper studies various manufacturing defects in glass fiber/Polypropylene (PP) composite parts and their methods of detection. Foreign Object Inclusion (FOI) of different shapes, sizes, and materials were placed in a glass fiber/PP panel made by compression molding. The paper aims to characterize the fiber orientation and fiber related defects such as fiber waviness in the composite specimen. Comprehensive investigation for different Non Destructive Evaluation (NDE) techniques, namely X-ray radiography and Ultrasonic Testing (UT) techniques to trace and characterize the embedded defects and the composite texture are presented. Conventional X-ray radiography successfully identified the fiber orientation in two dimension (2-D) plane; however, information for the sample depth was not captured. The radiography techniques showed low relative errors for the defect size measurements (maximum error was below 9.5%) when compared to the ultrasonic techniques. Ultrasonic techniques were able to map all the embedded artificial defects. Phase Array (PA) ultrasonic technique was able to precisely locate the FOI in the glass fiber/PP specimen. Nerveless, the shape and size of the defects were not accurately determined due to the high signal attenuation and distortion characteristics of the E-glass fiber.

  9. Evaluation of Transportation Options for Intermediate Non-destructive Examinations

    SciTech Connect

    Case, Susan; Hoggard, Gary

    2013-11-01

    Idaho National Laboratory (INL) shipments of irradiated experiments from the Advanced Test Reactor (ATR) to the Hot Fuels Examination Facility (HFEF) have historically been accomplished using the General Electric Model 2000 (GE 2000) Type B shipping container. Battelle Energy Alliance (BEA) concerns regarding the future availability and leasing and handling costs associated with the GE 2000 cask have warranted an evaluation of alternative shipping options. One or more of these shipping options may be utilized to perform non-destructive examinations (NDE) such as neutron radiography and precision gamma scans of irradiated experiments at HFEF and then return the experiments to ATR for further irradiation, hereafter referred to as “intermediate NDE.” This evaluation includes transportation options for intermediate NDE using the GE 2000 cask, BEA Research Reactor (BRR) package, Dry Transfer Cubicle (DTC) insert, and the General Electric Model 100 (GE 100) cask. The GE 2000 cask is the only Type B shipping container currently in use for shipments of irradiated material (exceeding Type A quantities) from ATR to HFEF; therefore it is included as one of the four shipping options in this evaluation. Cost and schedule estimates are provided for performing neutron radiography and precision gamma scans of a five-capsule drop-in-type ATR experiment for each transportation option. All costs provided in this evaluation are rough order-of-magnitude costs based on input from knowledgeable vendor employees and individuals at INL facilities.

  10. A novel thermosonic imaging system for non-destructive testing

    NASA Astrophysics Data System (ADS)

    Willey, C. L.; Xiang, D.; Long, M.

    2017-02-01

    Thermosonic infrared (Sonic IR) imaging is a new non-destructive testing (NDT) technique that uses high-frequency sonic excitation together with infrared (IR) detection to image surface and subsurface defects. A conventional Sonic IR imaging system employs an ultrasonic welder, which is designed to operate at a single frequency. This single frequency ultrasonic source has been found to yield a "blind zone" for NDT due to the formation of standing waves inside the test piece. To overcome this limitation, a spring loaded ultrasonic transducer was used to generate the desired multi-frequency acoustic chaos in the test object [1]. The limitation of the spring loaded ultrasonic transducer is its repeatability and reproducibility for field applications. In this work, we present the development of a novel thermosonic imaging system, which is capable of exciting the ultrasonic transducer at difflerent frequencies for thermosonic NDT to overcome the limitations associated with a single frequency power source as well as the spring loaded transducer design. A comparison of experimental results will be made between the single frequency and the developed multi-frequency thermosonic NDT systems.

  11. Non-destructive investigation of thermoplastic reinforced composites

    DOE PAGES

    Hassen, Ahmed; Taheri, Hossein; Vaidya, Uday

    2016-05-09

    This paper studies various manufacturing defects in glass fiber/Polypropylene (PP) composite parts and their methods of detection. Foreign Object Inclusion (FOI) of different shapes, sizes, and materials were placed in a glass fiber/PP panel made by compression molding. The paper aims to characterize the fiber orientation and fiber related defects such as fiber waviness in the composite specimen. Comprehensive investigation for different Non Destructive Evaluation (NDE) techniques, namely X-ray radiography and Ultrasonic Testing (UT) techniques to trace and characterize the embedded defects and the composite texture are presented. Conventional X-ray radiography successfully identified the fiber orientation in two dimension (2-D)more » plane; however, information for the sample depth was not captured. The radiography techniques showed low relative errors for the defect size measurements (maximum error was below 9.5%) when compared to the ultrasonic techniques. Ultrasonic techniques were able to map all the embedded artificial defects. Phase Array (PA) ultrasonic technique was able to precisely locate the FOI in the glass fiber/PP specimen. Nerveless, the shape and size of the defects were not accurately determined due to the high signal attenuation and distortion characteristics of the E-glass fiber.« less

  12. Non-Destructive Evaluation of Materials via Ultraviolet Spectroscopy

    NASA Technical Reports Server (NTRS)

    Pugel, Betsy

    2008-01-01

    A document discusses the use of ultraviolet spectroscopy and imaging for the non-destructive evaluation of the degree of cure, aging, and other properties of resin-based composite materials. This method can be used in air, and is portable for field use. This method operates in reflectance, absorbance, and luminescence modes. The ultraviolet source is used to illuminate a composite surface of interest. In reflectance mode, the reflected response is acquired via the imaging system or via the spectrometer. The spectra are analyzed for organic compounds (conjugated organics) and inorganic compounds (semiconducting band-edge states; luminescing defect states such as silicates, used as adhesives for composite aerospace applications; and metal oxides commonly used as thermal coating paints on a wide range of spacecraft). The spectra are compared with a database for variation in conjugation, substitution, or length of molecule (in the case of organics) or band edge position (in the case of inorganics). This approach is useful in the understanding of material quality. It lacks the precision in defining the exact chemical structure that is found in other materials analysis techniques, but it is advantageous over methods such as nuclear magnetic resonance, infrared spectroscopy, and chromatography in that it can be used in the field to assess significant changes in chemical structure that may be linked to concerns associated with weaknesses or variations in structural integrity, without disassembly of or destruction to the structure of interest.

  13. Non-destructive evaluation of anchorage zones by ultrasonics techniques.

    PubMed

    Kharrat, M; Gaillet, L

    2015-08-01

    This work aims to evaluate the efficiency and reliability of two Non-Destructive Testing (NDT) methods for damage assessment in bridges' anchorages. The Acousto-Ultrasonic (AU) technique is compared to classical Ultrasonic Testing (UT) in terms of defect detection and structural health classification. The AU technique is firstly used on single seven-wire strands damaged by artificial defects. The effect of growing defects on the waves traveling through the strands is evaluated. Thereafter, three specimens of anchorages with unknown defects are inspected by the AU and UT techniques. Damage assessment results from both techniques are then compared. The structural health conditions of the specimens can be then classified by a damage severity criterion. Finally, a damaged anchorage socket with mastered defects is controlled by the same techniques. The UT allows the detection and localization of damaged wires. The AU technique is used to bring out the effect of defects on acoustic features by comparing a healthy and damaged anchorage sockets. It is concluded that the UT method is suitable for local and crack-like defects, whereas the AU technique enables the assessment of the global structural health of the anchorage zones.

  14. Data fusion for automated non-destructive inspection

    PubMed Central

    Brierley, N.; Tippetts, T.; Cawley, P.

    2014-01-01

    In industrial non-destructive evaluation (NDE), it is increasingly common for data acquisition to be automated, driving a recent substantial increase in the availability of data. The collected data need to be analysed, typically necessitating the painstaking manual labour of a skilled operator. Moreover, in automated NDE a region of an inspected component is typically interrogated several times, be it within a single data channel due to multiple probe passes, across several channels acquired simultaneously or over the course of repeated inspections. The systematic combination of these diverse readings is recognized to offer an opportunity to improve the reliability of the inspection, but is not achievable in a manual analysis. This paper describes a data-fusion-based software framework providing a partial automation capability, allowing component regions to be declared defect-free to a very high probability while readily identifying defect indications, thereby optimizing the use of the operator's time. The system is designed to applicable to a wide range of automated NDE scenarios, but the processing is exemplified using the industrial ultrasonic immersion inspection of aerospace turbine discs. Results obtained for industrial datasets demonstrate an orders-of-magnitude reduction in false-call rates, for a given probability of detection, achievable using the developed software system. PMID:25002828

  15. Confounding and exposure measurement error in air pollution epidemiology.

    PubMed

    Sheppard, Lianne; Burnett, Richard T; Szpiro, Adam A; Kim, Sun-Young; Jerrett, Michael; Pope, C Arden; Brunekreef, Bert

    2012-06-01

    Studies in air pollution epidemiology may suffer from some specific forms of confounding and exposure measurement error. This contribution discusses these, mostly in the framework of cohort studies. Evaluation of potential confounding is critical in studies of the health effects of air pollution. The association between long-term exposure to ambient air pollution and mortality has been investigated using cohort studies in which subjects are followed over time with respect to their vital status. In such studies, control for individual-level confounders such as smoking is important, as is control for area-level confounders such as neighborhood socio-economic status. In addition, there may be spatial dependencies in the survival data that need to be addressed. These issues are illustrated using the American Cancer Society Cancer Prevention II cohort. Exposure measurement error is a challenge in epidemiology because inference about health effects can be incorrect when the measured or predicted exposure used in the analysis is different from the underlying true exposure. Air pollution epidemiology rarely if ever uses personal measurements of exposure for reasons of cost and feasibility. Exposure measurement error in air pollution epidemiology comes in various dominant forms, which are different for time-series and cohort studies. The challenges are reviewed and a number of suggested solutions are discussed for both study domains.

  16. Pollution exposure on marine protected areas: A global assessment.

    PubMed

    Partelow, Stefan; von Wehrden, Henrik; Horn, Olga

    2015-11-15

    Marine protected areas (MPAs) face many challenges in their aim to effectively conserve marine ecosystems. In this study we analyze the extent of pollution exposure on the global fleet of MPAs. This includes indicators for current and future pollution and the implications for regionally clustered groups of MPAs with similar biophysical characteristics. To cluster MPAs into characteristic signature groups, their bathymetry, baseline biodiversity, distance from shore, mean sea surface temperature and mean sea surface salinity were used. We assess the extent at which each signature group is facing exposure from multiple pollution types. MPA groups experience similar pollution exposure on a regional level. We highlight how the challenges that MPAs face can be addressed through governance at the appropriate scale and design considerations for integrated terrestrial and marine management approaches within regional level networks. Furthermore, we present diagnostic social-ecological indicators for addressing the challenges facing unsuccessful MPAs with practical applications.

  17. Genomics and the respiratory effects of air pollution exposure.

    PubMed

    Holloway, John W; Savarimuthu Francis, Santiyagu; Fong, Kwun M; Yang, Ian A

    2012-05-01

    Adverse health effects from air pollutants remain important, despite improvement in air quality in the past few decades. The exact mechanisms of lung injury from exposure to air pollutants are not yet fully understood. Studying the genome (e.g. single-nucleotide polymorphisms (SNP) ), epigenome (e.g. methylation of genes), transcriptome (mRNA expression) and microRNAome (microRNA expression) has the potential to improve our understanding of the adverse effects of air pollutants. Genome-wide association studies of SNP have detected SNP associated with respiratory phenotypes; however, to date, only candidate gene studies of air pollution exposure have been performed. Changes in epigenetic processes, such DNA methylation that leads to gene silencing without altering the DNA sequence, occur with air pollutant exposure, especially global and gene-specific methylation changes. Respiratory cell line and animal models demonstrate distinct gene expression signatures in the transcriptome, arising from exposure to particulate matter or ozone. Particulate matter and other environmental toxins alter expression of microRNA, which are short non-coding RNA that regulate gene expression. While it is clearly important to contain rising levels of air pollution, strategies also need to be developed to minimize the damaging effects of air pollutant exposure on the lung, especially for patients with chronic lung disease and for people at risk of future lung disease. Careful study of genomic responses will improve our understanding of mechanisms of lung injury from air pollution and enable future clinical testing of interventions against the toxic effects of air pollutants. © 2012 The Authors. Respirology © 2012 Asian Pacific Society of Respirology.

  18. Metal Pollutant Exposure and Behavior Disorders: Implications for School Practices.

    ERIC Educational Resources Information Center

    Marlowe, Mike

    1986-01-01

    The article summarizes research on relationships between low (below metal poisoning) metal exposure and childhood behavior disorders. Symptoms, assessment techniques (hair analysis), and environmental and dietary factors that may increase the risk of metal pollutant exposure are described. School programs emphasizing education and the role of…

  19. Geophysical Methods for Non-Destructive Testing in Civil Engineering

    NASA Astrophysics Data System (ADS)

    Niederleithinger, E.

    2013-12-01

    Many non-destructive testing (NDT) methods for civil engineering (e. g. ultrasonics, radar) are similar to geophysical techniques. They just differ in scale, material under investigation and vocabulary used. In spite of the fact that the same principles of physics and mathematics apply to both fields, exchange has been limited in the past. But since a few years more and more geophysical knowledge is used in civil engineering. One of the focal points in research is to improve ultrasonic testing of concrete to be able to image the inside even of large, complex structures and to detect any deterioration as early as possible. One of the main issues is the heterogeneity of concrete, including aggregates, reinforcement, cracks and many other features. Our current research focuses on three points. One is the application of state of the art geophysical migration techniques as Reverse Time Migration (RTM) to image vertical faces or the backside of voids and ducts in thick concrete structures, which isn't possible with conventional techniques used in NDT. Second, we have started to use seismic interferometric techniques to interpolate ultrasonic traces, which can't be measured directly for technical reasons. Third, we are using coda wave interferometry to detect concrete degradation due to load, fatigue, temperature or other influences as early as possible. Practical examples of the application of these techniques are given and potential future research directions will be discussed. It will be shown, how a subset of these techniques can be used for innovative monitoring systems for civil infrastructure. Imaging the interior of a concrete body by ultrasonics and reverse time migration(simulated data).

  20. Non Destructive Analysis of Fsw Welds using Ultrasonic Signal Analysis

    NASA Astrophysics Data System (ADS)

    Pavan Kumar, T.; Prabhakar Reddy, P.

    2017-08-01

    Friction Stir Welding is an evolving metal joining technique and is mostly used in joining materials which cannot be easily joined by other available welding techniques. It is a technique which can be used for welding dissimilar materials also. The strength of the weld joint is determined by the way in which these material are mixing with each other, since we are not using any filler material for the welding process the intermixing has a significant importance. The complication with the friction stir welding process is that there are many process parameters which effect this intermixing process such as tool geometry, rotating speed of the tool, transverse speed etc., In this study an attempt is made to compare the material flow and weld quality of various weldments by changing the parameters. Ultrasonic signal Analysis is used to characterize the microstructure of the weldments. use of ultrasonic waves is a non destructive, accurate and fast way of characterization of microstructure. In this method the relationship between the ultrasonic measured parameters and microstructures are evaluated using background echo and backscattered signal process techniques. The ultrasonic velocity and attenuation measurements are dependent on the elastic modulus and any change in the microstructure is reflected in the ultrasonic velocity. An insight into material flow is essential to determine the quality of the weld. Hence an attempt is made in this study to know the relationship between tool geometry and the pattern of material flow and resulting weld quality the experiments are conducted to weld dissimilar aluminum alloys and the weldments are characterized using and ultra Sonic signal processing. Characterization is also done using Scanning Electron Microscopy. It is observed that there is a good correlation between the ultrasonic signal processing results and Scanning Electron Microscopy on the observed precipitates. Tensile tests and hardness tests are conducted on the

  1. Non-destructive detection of corrosion for life management

    NASA Astrophysics Data System (ADS)

    Bruce, David A.

    1995-01-01

    In recent years, aircraft operators have been driven to increased use of Non-Destructive Evaluation (NDE) to ensure airworthiness during life extensions for ageing aircraft or as an integral part of a damage tolerant lifting philosophy. Major airframe static and fatigue tests are routinely used to highlight problem areas on airframes where design limitations or changes of usage may lead to early failures. The results of such tests become progressively less reliable as the age of the airframe increases and the operating conditions diverge from those under which the tests were conducted. Increased inspection, whether by visual or other means is usually the only alternative to wholesale refurbishment or replacement of aircraft or components. Almost all of the development to date of NDE techniques for corrosion detection and characterization has been concentrated on existing airframe materials, principally Aluminum alloys and steels. The current capabilities of corrosion detection techniques will be reviewed and current research aimed at areas where there is a requirement for improved detection capability will be described. New materials, such as Polymer Matrix Composites, will experience different types of 'corrosive' deterioration. The capability of NDE methods to detect material degradation in new composite materials will be discussed. Finally, reliance on NDE, choice of NDE technique and optimal scheduling of inspections all require an assessment of the reliability of NDE methods. It will be shown that a range of NDE techniques with differing capabilities and characteristics will be required to ensure compatibility with maintenance schedules if full use is to be made of NDE for life management of structures which may be subject to corrosion.

  2. Rapid, non-destructive coral paleothermometry by synchrotron XR

    NASA Astrophysics Data System (ADS)

    Tangri, N.; Mehta, A.; Marks, R.; Dunbar, R. B.

    2016-12-01

    We present advances in the use of synchrotron x-ray fluorescence (XRF) to recover climate signals from coral exoskeleton. Corals record sea surface temperature (SST), salinity, and other environmental conditions in the density and composition of their exoskeletons; in particular, SST is reflected in both the Sr/Ca ratio and the annual density banding. Synchrotron XRF has previously been used to examine the fine-scaled variability of Sr concentrations in the exoskeleton structure, but has not yet yielded any long-term SST reconstructions. Modern XRF techniques allow the detection of sub-ppm trace element concentrations and appear ideally suited to long climate reconstructions, as they are non-destructive, high-resolution (250 um) and potentially quite rapid ( 40 years of sample in 24 hours of instrument time). The low Sr content of the coral and its low change in concentration require a high brightness synchrotron source to generate a high signal-to-background ratio. However, difficulties arise from the local heterogeneity of Sr that is unrelated to environmental conditions. These variations of biological origin in Sr concentrations often mask the smaller-amplitude, annual and interannual SST signals. The challenge is to normalize the local variability in order to extract the climate signal. Other techniques have normalized against Ca, but in XRF the Ca signal is sensitive to only the surface 50 um of material, whereas the Sr signal comes from 1mm, so the values are not comparable. Instead, we normalize against density as calculated from beam transmission. We also explore the use of Rb normalization to filter out collection artifacts. Both Sr and Rb show strong annual signals and interesting departures from the density signal. Finally, we pair the XRF results with δ18O measurements to recover a convincing record of SST variation. Although challenges remain, we believe that synchrotron XRF techniques hold considerable promise to rapidly and accurately recover

  3. An empirical assessment of exposure measurement error and effect attenuation in bi-pollutant epidemiologic models

    EPA Science Inventory

    Background: Using multipollutant models to understand combined health effects of exposure to multiple pollutants is becoming more common. However, complex relationships between pollutants and differing degrees of exposure error across pollutants can make health effect estimates f...

  4. An empirical assessment of exposure measurement errors and effect attenuation in bi-pollutant epidemiologic models

    EPA Science Inventory

    Using multipollutant models to understand the combined health effects of exposure to multiple pollutants is becoming more common. However, the complex relationships between pollutants and differing degrees of exposure error across pollutants can make health effect estimates from ...

  5. An empirical assessment of exposure measurement errors and effect attenuation in bi-pollutant epidemiologic models

    EPA Science Inventory

    Using multipollutant models to understand the combined health effects of exposure to multiple pollutants is becoming more common. However, the complex relationships between pollutants and differing degrees of exposure error across pollutants can make health effect estimates from ...

  6. An empirical assessment of exposure measurement error and effect attenuation in bi-pollutant epidemiologic models

    EPA Science Inventory

    Background: Using multipollutant models to understand combined health effects of exposure to multiple pollutants is becoming more common. However, complex relationships between pollutants and differing degrees of exposure error across pollutants can make health effect estimates f...

  7. Non-Destructive Damping Measurement for Wafer-Level Packaged Microelectromechanical System (MEMS) Acceleration Switches

    DTIC Science & Technology

    2014-09-01

    logarithmic decrement of those amplitudes.7,8 Experiments that did not rely on resonant frequencies used capacitance measurements or pressure sensors to relate...Non-destructive Damping Measurement for Wafer- level Packaged Microelectromechanical System (MEMS) Acceleration Switches by Ryan Knight and...Laboratory Adelphi, MD 20783-1138 ARL-TR-7094 September 2014 Non-destructive Damping Measurement for Wafer- level Packaged

  8. Recent advances in the use of non-destructive near infrared spectroscopy on intact olive fruits

    USDA-ARS?s Scientific Manuscript database

    The objective of this review is to illustrate the state of the art in the use of non-destructive near infrared (NIR) spectroscopy for quality evaluation of intact fruit in the olive industry. First, the most recent studies regarding the application of non-destructive NIR spectroscopy methods to asse...

  9. Non-destructive determination of maize leaf and canopy chlorophyll content

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to develop a rapid non-destructive technique to estimate total chlorophyll (Chl) content in a maize canopy using Chl content in a single leaf. The approach was (1) to calibrate and validate a reflectance-based non-destructive technique to estimate leaf Chl in maize; (...

  10. A case of azoospermia in a non-destructive testing worker exposed to radiation.

    PubMed

    Park, Jaechan; Lee, Sanggil; Park, Chulyong; Eom, Huisu

    2017-01-01

    Interest in radiation-related health problems has been growing with the increase in the number of workers in radiation-related jobs. Although an occupational level of radiation exposure would not likely cause azoospermia, several studies have reported the relation between radiation exposure and azoospermia after accidental or therapeutic radiation exposure. We describe a case of azoospermia in a non-destructive testing (NDT) worker exposed to radiation and discuss the problems of the related monitoring system. A 39-year-old man who was childless after 8 years of marriage was diagnosed with azoospermia through medical evaluations, including testicular biopsy. He did not have any abnormal findings on biochemical evaluations, other risk factors, or evidence of congenital azoospermia. He had been working in an NDT facility from 2005 to 2013, attaching and arranging gamma-ray films on the structures and inner spaces of ships. The patient's thermoluminescent dosimeter (TLD) badge recorded an exposure level of 0.01781 Gy for 80 months, whereas results of his florescence in situ hybridization (FISH) translocation assay showed an exposure level of up to 1.926 Gy of cumulative radiation, which was sufficient to cause azoospermia. Thus, we concluded that his azoospermia was caused by occupational radiation exposure. The difference between the exposure dose records measured through TLD badge and the actual exposure dose implies that the monitor used by the NDT worker did not work properly, and such a difference could threaten the health and safety of workers. Thus, to protect the safety and health of NDT workers, education of workers and strengthening of law enforcement are required to ensure that regulations are strictly followed, and if necessary, random sampling of NDT workers using a cytogenetic dosimeter, such as FISH, should be considered.

  11. Urban atmospheric pollution: personal exposure versus fixed monitoring station measurements.

    PubMed

    Violante, Francesco S; Barbieri, Anna; Curti, Stefania; Sanguinetti, Giovanni; Graziosi, Francesca; Mattioli, Stefano

    2006-09-01

    We initiated the PETER (pedestrian environmental traffic pollutant exposure research) project to investigate pedestrians' exposure to traffic related atmospheric pollutants, based on data obtained with the collaboration of selected categories of pedestrian urban workers. We investigated relations between roadside personal exposure levels of volatile aromatic hydrocarbons (including benzene) and particulate matter <10 microm (PM10) among traffic police (n = 126) and parking wardens (n = 50) working in downtown Bologna, Italy. Data were collected from workshifts throughout four 1-week periods in different seasons of 2000-2001. For benzene and PM10, comparisons were made with measurements by fixed monitoring stations, and influence of localized traffic intensity and meteorological parameters was examined. Roadside personal exposure to benzene correlated more strongly with other volatile aromatic hydrocarbons (toluene, xylenes and ethylbenzene) than with PM10. Benzene and PM10 personal exposure levels were higher than fixed monitoring station values (both p<0.0001). At multivariate analysis, benzene and PM10 data from fixed monitoring stations both correlated with meteorological variables, and were also influenced by localized traffic intensity. Plausibly because of the downtown canyon-like streets, weather conditions (during a period of drought) only marginally affected benzene personal exposure, and moderately affected PM10 personal exposure. These findings reinforce the concept that urban atmospheric pollution data from fixed air monitoring stations cannot automatically be taken as indications of roadside exposures.

  12. Ambient air pollution exposure and blood pressure changes during pregnancy

    PubMed Central

    Lee, Pei-Chen; Talbott, Evelyn O.; Roberts, James M.; Catov, Janet M.; Bilonick, Richard A.; Stone, Roslyn A.; Sharma, Ravi K.; Ritz, Beate

    2013-01-01

    Background Maternal exposure to ambient air pollution has been associated with adverse birth outcomes such as preterm delivery. However, only one study to date has linked air pollution to blood pressure changes during pregnancy, a period of dramatic cardiovascular function changes. Objectives We examined whether maternal exposures to criteria air pollutants, including particles of less than 10 µm (PM10) or 2.5 µm diameter (PM2.5), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3), in each trimester of pregnancy are associated with magnitude of rise of blood pressure between the first 20 weeks of gestation and late pregnancy in a prospectively followed cohort of 1684 pregnant women in Allegheny County, PA. Methods Air pollution measures for maternal ZIP code areas were derived using Kriging interpolation. Using logistic regression analysis, we evaluated the associations between air pollution exposures and blood pressure changes between the first 20 weeks of gestation and late pregnancy. Results First trimester PM10 and ozone exposures were associated with blood pressure changes between the first 20 weeks of gestation and late pregnancy, most strongly in non-smokers. Per interquartile increases in first trimester PM10 and O3 concentrations were associated with mean increases in systolic blood pressure of 1.88 mmHg (95% CI = 0.84 to 2.93) and 1.84 (95% CI = 1.05 to 4.63), respectively, and in diastolic blood pressure of 0.63 mmHg (95% CI= −0.50 to 1.76) and 1.13 (95% CI= −0.46 to 2.71) in non-smokers. Conclusions Our novel finding suggests that first trimester PM10 and O3 air pollution exposures increase blood pressure in the later stages of pregnancy. These changes may play a role in mediating the relationships between air pollution and adverse birth outcomes. PMID:22835955

  13. Thermal history sensors for non-destructive temperature measurements in harsh environments

    SciTech Connect

    Pilgrim, C. C.; Heyes, A. L.; Feist, J. P.

    2014-02-18

    The operating temperature is a critical physical parameter in many engineering applications, however, can be very challenging to measure in certain environments, particularly when access is limited or on rotating components. A new quantitative non-destructive temperature measurement technique has been proposed which relies on thermally induced permanent changes in ceramic phosphors. This technique has several distinct advantages over current methods for many different applications. The robust ceramic material stores the temperature information allowing long term thermal exposures in harsh environment to be measured at a convenient time. Additionally, rare earth dopants make the ceramic phosphorescent so that the temperature information can be interpreted by automated interrogation of the phosphorescent light. This technique has been demonstrated by application of YAG doped with dysprosium and europium as coatings through the air-plasma spray process. Either material can be used to measure temperature over a wide range, namely between 300°C and 900°C. Furthermore, results show that the material records the peak exposure temperature and prolonged exposure at lower temperatures would have no effect on the temperature measurement. This indicates that these materials could be used to measure peak operating temperatures in long-term testing.

  14. MANAGING EXPOSURES TO NEUROTOXIC AIR POLLUTANTS.

    EPA Science Inventory

    Researchers at EPA's National Health and Environmental Effects Research Laboratory are developing a biologically-based dose-response model to describe the neurotoxic effects of exposure to volatile organic compounds (VOCs). The model is being developed to improve risk assessment...

  15. MANAGING EXPOSURES TO NEUROTOXIC AIR POLLUTANTS.

    EPA Science Inventory

    Researchers at EPA's National Health and Environmental Effects Research Laboratory are developing a biologically-based dose-response model to describe the neurotoxic effects of exposure to volatile organic compounds (VOCs). The model is being developed to improve risk assessment...

  16. Assessing human exposure to airborne pollutants: Advances and opportunities

    SciTech Connect

    Lioy, P.J. )

    1991-08-01

    A committee which was convened by the National Research Council, recently completed an analysis of new methods and technologies for assessing exposure to air pollutants. The committee identified three major ways of determining human exposure to airborne pollutants. Monitoring the air around an individual with a portable personal air sampler is, of course, the most comprehensive and most accurate. It is also the costliest and most time consuming. The second method is more indirect and involves techniques such as measuring the amount of a contaminant with a stationary monitor and extrapolating exposure by means of personal activity records or mathematical models. Exposure to carbon monoxide inside a car, for example, might be roughly calculated from the amount of time spent in the car and the quantity of carbon monoxide in the car under typical operating conditions. The third method involves biological markers as a measure of the integrated dose within the body and of past contact with pollutants. For example, a marker for airborne lead exposure can be elevated lead levels in the blood. However, this must be weighed against contributions from other media. A final and major point made in the report is the need to have accurate and realistic assessments to ensure optimal reduction of human exposure. To accomplish this, exposure assessment research should be supported by government programs. Although not stated, such research should also be supported by other sectors, including the regulated community.

  17. Non-destructive hyperspectral imaging of quarantined Mars Returned Samples

    NASA Astrophysics Data System (ADS)

    Simionovici, Alexandre; Viso, Michel; Beck, Pierre; Lemelle, Laurence; Westphal, Andrew; Vincze, Laszlo; Schoonjans, Tom; Fihman, Francois; Chazalnoel, Pascale; Ferroir, Tristan; Solé, Vicente Armando; Tucoulou, R.

    Introduction: In preparation for the upcoming International Mars Sample Return mission (MSR), returning samples containing potential biohazards, we have implemented a hyperspec-tral method of in-situ analysis of grains performed in BSL4 quarantine conditions, by combining several non-destructive imaging diagnostics. This allows sample transportation on optimized experimental setups, while monitoring the sample quarantine conditions. Our hyperspectral methodology was tested during analyses of meteorites [1-2] and cometary and interstellar grains from the recent NASA Stardust mission [3-6]. Synchrotron Radiation protocols: X-ray analysis methods are widely accepted as the least destructive probes of fragile, unique samples. Diffraction, X-ray fluorescence and ab-sorption micro/nano-spectroscopies were performed on chondritic test samples using focused monochromatic beams at the ESRF synchrotron in Grenoble, France. 2D maps of grain com-position down to ppm concentrations and polycrystalline structure have simultaneously been acquired, followed by X-ray absorption performed on elements of Z 26. Ideally, absorption micro-tomography can later be performed in full-beam mode to record the 3D morphology of the grain followed by fluorescence-tomography in focus-beam mode which complements this picture with a 3D elemental image of the grain. Lab-based protocols: Raman and IR-based spectroscopies have been performed in reflection mode for mineralogical imaging of the grains in the laboratory using commercial microscopes. The spatial resolution varied in the 1-10 m range. Laser limited penetration of opaque samples permits only 2D imaging of the few nanometer-thick outer layers of the grains. Mineralogical maps are now routinely acquired using Raman spectroscopy at sub-micron scales through the 3 container walls of the Martian sample holder, followed by IR few-micrometer spot measurements recording C-based and potential aqueous alteration distributions. Sample Holder: A

  18. Assessment of planctomycetes cell viability after pollutants exposure.

    PubMed

    Flores, Carlos; Catita, José A M; Lage, Olga Maria

    2014-08-01

    In this study, the growth of six different planctomycetes, a particular ubiquitous bacterial phylum, was assessed after exposure to pollutants. In addition and for comparative purposes, Pseudomonas putida, Escherichia coli and Vibrio anguillarum were tested. Each microorganism was exposed to several concentrations of 21 different pollutants. After exposure, bacteria were cultivated using the drop plate method. In general, the strains exhibited a great variation of sensitivity to pollutants in the order: V. anguillarum > planctomycetes > P. putida > E. coli. E. coli showed resistance to all pollutants tested, with the exception of phenol and sodium azide. Copper, Ridomil® (fungicide), hydrazine and phenol were the most toxic pollutants. Planctomycetes were resistant to extremely high concentrations of nitrate, nitrite and ammonium but they were the only bacteria sensitive to Previcur N® (fungicide). Sodium azide affected the growth on plates of E. coli, P. putida and V. anguillarum, but not of planctomycetes. However, this compound affected planctomycetes cell respiration but with less impact than in the aforementioned bacteria. Our results provide evidence for a diverse response of bacteria towards pollutants, which may influence the structuring of microbial communities in ecosystems under stress, and provide new insights on the ecophysiology of planctomycetes.

  19. Approaches to characterize inequities in air pollution exposures

    EPA Science Inventory

    Certain populations bear a disproportionate burden of air pollutant exposures resulting in inequity of risk. This may be due to proximity to outdoor sources such as major roadways and industry or increased prevalence of indoor sources such as cigarette smoking or gas stoves. Ther...

  20. RESPIRATORY EPIDEMIOLOGY OF HOUSEHOLD AIR POLLUTION EXPOSURES IN DEVELOPING COUNTRIES

    EPA Science Inventory

    Acute and chronic respiratory diseases impose a huge public health burden in the developing world. A large and growing body of scientific evidence indicates that household air pollution exposures contribute substantially to this burden. The most important source of indoor air p...

  1. RESPIRATORY EPIDEMIOLOGY OF HOUSEHOLD AIR POLLUTION EXPOSURES IN DEVELOPING COUNTRIES

    EPA Science Inventory

    Acute and chronic respiratory diseases impose a huge public health burden in the developing world. A large and growing body of scientific evidence indicates that household air pollution exposures contribute substantially to this burden. The most important source of indoor air p...

  2. Approaches to characterize inequities in air pollution exposures

    EPA Science Inventory

    Certain populations bear a disproportionate burden of air pollutant exposures resulting in inequity of risk. This may be due to proximity to outdoor sources such as major roadways and industry or increased prevalence of indoor sources such as cigarette smoking or gas stoves. Ther...

  3. Assessment of human exposure to gaseous pollutants

    SciTech Connect

    Baskin, L.B.; Falco, J.W. )

    1989-09-01

    A mathematical model to aid in assessment of human environmental exposure to volatile organic substances is presented. The model simulates the convective and diffusive transport of gas from the ambient environment into the human body by way of the respiratory and circulatory systems. Data required include easily obtained physical and chemical properties of substances as well as several estimated or measured physiological parameters. Transient and steady-state tissue concentrations resulting from an input atmospheric partial pressure are predicted. From these concentrations, an effective dose may be calculated, allowing for the determination of an exposure-response relationship based upon independently obtained dose-response data. The model's results compare favorably to experimental data on oxygen and halothane. Steady-state conditions are reached very rapidly. These results suggest that uptake of these substances is limited by both ventilation and perfusion. Rates are demonstrated to be essentially linear within the current neighborhoods. Conditions in which the primary processes of ventilation, diffusion, perfusion, and elimination limit uptake of gases are considered. Expressions describing the conditions necessary for a single process to limit gas uptake are derived. Accompanying equations for estimating tissue concentrations under these limiting conditions are presented.

  4. Assessing Exposure to Household Air Pollution: A Systematic ...

    EPA Pesticide Factsheets

    ACKGROUND: Household air pollution from solid fuel burning is a leading contributor to disease burden globally. Fine particulate matter (PM2.5) is thought to be responsible for many of these health impacts. A co-pollutant, carbon monoxide (CO) has been widely used as a surrogate measure of PM2.5 in studies of household air pollution. OBJECTIVE: The goal was to evaluate the validity of exposure to CO as a surrogate of exposure to PM2.5 in studies of household air pollution and the consistency of the PM2.5–CO relationship across different study settings and conditions. METHODS: We conducted a systematic review of studies with exposure and/or cooking area PM2.5 and CO measurements and assembled 2,048 PM2.5 and CO measurements from a subset of studies (18 cooking area studies and 9 personal exposure studies) retained in the systematic review. We conducted pooled multivariate analyses of PM2.5–CO associations, evaluating fuels, urbanicity, season, study, and CO methods as covariates and effect modifiers. RESULTS: We retained 61 of 70 studies for review, representing 27 countries. Reported PM2.5–CO correlations (r) were lower for personal exposure (range: 0.22–0.97; median=0.57) than for cooking areas (range: 0.10–0.96; median=0.71). In the pooled analyses of personal exposure and cooking area concentrations, the variation in ln(CO) explained 13% and 48% of the variation in ln(PM2.5), respectively. CONCLUSIONS: Our results suggest that exposure to CO is not

  5. A novel method for non-destructive determination of hair photo-induced damage based on multispectral imaging technology

    PubMed Central

    Cao, Yue; Qu, Hao; Xiong, Can; Liu, Changhong; Zheng, Lei

    2017-01-01

    Extended exposure to sunlight may give rise to chemical and physical damages of human hairs. In this work, we report a novel method for non-destructive quantification of hair photodamage via multispectral imaging (MSI) technology. We show that the multispectral reflectance value in near-infrared region has a strong correlation with hair photodamage. More specifically, the hair segments with longer growing time and the same hair root segment after continuous ultraviolet (UV) irradiation displaying more severe photodamage observed via scanning electron microscopy (SEM) micrographs showed significantly higher multispectral reflectance value. Besides, the multispectral reflectance value of hair segments with different growing time was precisely reproduced by exposing the same hair root segment to specific durations of UV irradiation, suggesting that MSI can be adequately applied to determine the sunlight exposure time of the hair. The loss of cystine content of photodamaged hairs was identified to be the main factor that physiologically contributed to the morphological changes of hair surface fibers and hence the variation of their multispectral reflectance spectra. Considering the environmental information recording nature of hairs, we believe that MSI for non-destructive evaluation of hair photodamage would prove valuable for assessing sunlight exposure time of a subject in the biomedical fields. PMID:28361876

  6. A novel method for non-destructive determination of hair photo-induced damage based on multispectral imaging technology.

    PubMed

    Cao, Yue; Qu, Hao; Xiong, Can; Liu, Changhong; Zheng, Lei

    2017-03-31

    Extended exposure to sunlight may give rise to chemical and physical damages of human hairs. In this work, we report a novel method for non-destructive quantification of hair photodamage via multispectral imaging (MSI) technology. We show that the multispectral reflectance value in near-infrared region has a strong correlation with hair photodamage. More specifically, the hair segments with longer growing time and the same hair root segment after continuous ultraviolet (UV) irradiation displaying more severe photodamage observed via scanning electron microscopy (SEM) micrographs showed significantly higher multispectral reflectance value. Besides, the multispectral reflectance value of hair segments with different growing time was precisely reproduced by exposing the same hair root segment to specific durations of UV irradiation, suggesting that MSI can be adequately applied to determine the sunlight exposure time of the hair. The loss of cystine content of photodamaged hairs was identified to be the main factor that physiologically contributed to the morphological changes of hair surface fibers and hence the variation of their multispectral reflectance spectra. Considering the environmental information recording nature of hairs, we believe that MSI for non-destructive evaluation of hair photodamage would prove valuable for assessing sunlight exposure time of a subject in the biomedical fields.

  7. The Evaluation of Alternative Exposure Metrics for Traffic-related Air Pollutant Exposure in North Carolina

    EPA Science Inventory

    Transportation plays an important role in the modern society but can cause significant health impacts. To quantify the associated health impacts, an appropriate traffic-related air pollution exposure metric is required. In this study, we evaluate the suitability of four exposure ...

  8. The Evaluation of Alternative Exposure Metrics for Traffic-related Air Pollutant Exposure in North Carolina

    EPA Science Inventory

    Transportation plays an important role in the modern society but can cause significant health impacts. To quantify the associated health impacts, an appropriate traffic-related air pollution exposure metric is required. In this study, we evaluate the suitability of four exposure ...

  9. Exposure scenarios and guidance values for urban soil pollutants.

    PubMed

    Boyd, H B; Pedersen, F; Cohr, K H; Damborg, A; Jakobsen, B M; Kristensen, P; Samsøe-Petersen, L

    1999-12-01

    In general, risk assessments of urban soil pollution are prepared by comparing the levels of pollutants with soil quality criteria. However, large urban areas are contaminated with concentrations of pollutants far exceeding the existing soil quality criteria and would consequently be considered to be of potential risk to humans. This is, however, a rather rigid approach, and for risk management purposes it would be desirable to have more than just one level of soil quality criteria. Therefore, a generic risk assessment model was developed for five different use scenarios: child-care centers, kitchen gardens, ornamental gardens, parks, and sports grounds. In each of the scenarios, three different types of expected behavior are described for children and adults, respectively, resulting in different levels of exposure to the pollutants. For risk management purposes, various guidance values can then be derived for each use scenario. Below a lower guidance value, a free use of the area according to the defined use is possible without an unacceptable risk to the public. Above an upper value, a cutoff of the exposure is necessary. In between, the use may be regulated by different types of advice. The model is still preliminary but was, however, used for derivation of guidance values for five commonly found soil pollutants, of which the results for benzo[a]pyrene and lead are presented.

  10. Simultaneous Exposure to Multiple Air Pollutants Influences Alveolar Epithelial Cell Ion Transport

    EPA Science Inventory

    Purpose. Air pollution sources generally release multiple pollutants simultaneously and yet, research has historically focused on the source-to-health linkages of individual air pollutants. We recently showed that exposure of alveolar epithelial cells to a combination of particul...

  11. Theoretical neutron damage calculations in industrial robotic manipulators used for non-destructive imaging applications

    SciTech Connect

    Hashem, Joseph; Schneider, Erich; Pryor, Mitch; Landsberger, Sheldon

    2017-01-01

    Our paper describes how to use MCNP to evaluate the rate of material damage in a robot incurred by exposure to a neutron flux. The example used in this work is that of a robotic manipulator installed in a high intensity, fast, and collimated neutron radiography beam port at the University of Texas at Austin's TRIGA Mark II research reactor. Our effort includes taking robotic technologies and using them to automate non-destructive imaging tasks in nuclear facilities where the robotic manipulator acts as the motion control system for neutron imaging tasks. Simulated radiation tests are used to analyze the radiation damage to the robot. Once the neutron damage is calculated using MCNP, several possible shielding materials are analyzed to determine the most effective way of minimizing the neutron damage. Furthermore, neutron damage predictions provide users the means to simulate geometrical and material changes, thus saving time, money, and energy in determining the optimal setup for a robotic system installed in a radiation environment.

  12. Theoretical neutron damage calculations in industrial robotic manipulators used for non-destructive imaging applications

    DOE PAGES

    Hashem, Joseph; Schneider, Erich; Pryor, Mitch; ...

    2017-01-01

    Our paper describes how to use MCNP to evaluate the rate of material damage in a robot incurred by exposure to a neutron flux. The example used in this work is that of a robotic manipulator installed in a high intensity, fast, and collimated neutron radiography beam port at the University of Texas at Austin's TRIGA Mark II research reactor. Our effort includes taking robotic technologies and using them to automate non-destructive imaging tasks in nuclear facilities where the robotic manipulator acts as the motion control system for neutron imaging tasks. Simulated radiation tests are used to analyze the radiationmore » damage to the robot. Once the neutron damage is calculated using MCNP, several possible shielding materials are analyzed to determine the most effective way of minimizing the neutron damage. Furthermore, neutron damage predictions provide users the means to simulate geometrical and material changes, thus saving time, money, and energy in determining the optimal setup for a robotic system installed in a radiation environment.« less

  13. The relationship between exposure to air pollution and sperm disomy.

    PubMed

    Jurewicz, Joanna; Radwan, Michał; Sobala, Wojciech; Polańska, Kinga; Radwan, Paweł; Jakubowski, Lucjusz; Ulańska, Anna; Hanke, Wojciech

    2015-01-01

    The causes of the chromosome abnormalities have been studied for decades. It has been suggested that exposure to various environmental agents can induce chromosomal abnormalities in germ cells. This study was designed to address the hypothesis that exposure to specific air pollutants increases sperm disomy. The study population consisted of 212 men who were attending an infertility clinic for diagnostic purposes. They represented a subset of men in a multicenter parent study conducted in Poland to evaluate environmental factors and male fertility. Sperm aneuploidy for chromosomes 13, 18, 21, X, and Y was assessed using multicolor fluorescence in situ hybridization. Air quality data were obtained from the AirBase database. After adjusting for age, smoking, alcohol consumption, temperature (90 days), season, past diseases, abstinence interval, distance from the monitoring station, concentration, motility and morphology, positive associations were observed between exposure to PM2.5 and disomy Y (P = 0.001), sex chromosome disomy (P = 0.05) and disomy 21 (P = 0.03). Exposure to PM10 was associated with disomy 21 (P = 0.02). Conversely, exposure to ozone, CO, SO2, and NOx did not affect sperm aneuploidy. A separate analysis conducted among men who were nonsmokers (n = 117) showed that the relationship between PM2.5 and disomy Y and disomy 21 remained significant (P = 0.01, P = 0.05, respectively). The present findings indicate that exposure to air pollution induces sperm aneuploidy. © 2014 Wiley Periodicals, Inc.

  14. Commuting behaviors and exposure to air pollution in Montreal, Canada.

    PubMed

    Miao, Qun; Bouchard, Michèle; Chen, Dongmei; Rosenberg, Mark W; Aronson, Kristan J

    2015-03-01

    Vehicular traffic is a major source of outdoor air pollution in urban areas, and studies have shown that air pollution is worse during hours of commuting to and from work and school. However, it is unclear to what extent different commuting behaviors are a source of air pollution compared to non-commuters, and if air pollution exposure actually differs by the mode of commuting. This study aimed to examine the relationships between commuting behaviors and air pollution exposure levels measured by urinary 1-OHP (1-hydroxypyrene), a biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs). A cross-sectional study of 174 volunteers living in Montreal, 92 females and 82 males, aged 20 to 53 years was conducted in 2011. Each participant completed a questionnaire regarding demographic factors, commuting behaviors, home and workplace addresses, and potential sources of PAH exposure, and provided a complete first morning void urine sample for 1-OHP analysis. Multivariable general linear regression models were used to examine the relationships between different types of commuting and urinary 1-OHP levels. Compared to non-commuters, commuters traveling by foot or bicycle and by car or truck had a significantly higher urinary 1-OHP concentration in urine (p=0.01 for foot or bicycle vs. non-commuters; p=0.02 for car or truck vs. non-commuters); those traveling with public transportation and combinations of two or more types of modes tended to have an increased 1-OHP level in urine (p=0.06 for public transportation vs. non-commuters; p=0.05 for commuters with combinations of two or more types of modes vs. non-commuters). No significant difference in urinary 1-OHP variation was found by mode of commuting. This preliminary study suggests that despite the mode of commuting, all types of commuting during rush hours increase exposure to air pollution as measured by a sensitive PAH metabolite biomarker, and mode of commuting did not explain exposure variation. Copyright

  15. Modeling Air Pollution Exposure Metrics for the Diabetes and Environment Panel Study (DEPS)

    EPA Science Inventory

    Air pollution health studies of fine particulate matter (PM) often use outdoor concentrations as exposure surrogates. To improve exposure assessments, we developed and evaluated an exposure model for individuals (EMI), which predicts five tiers of individual-level exposure metric...

  16. Modeling Air Pollution Exposure Metrics for the Diabetes and Environment Panel Study (DEPS)

    EPA Science Inventory

    Air pollution health studies of fine particulate matter (PM) often use outdoor concentrations as exposure surrogates. To improve exposure assessments, we developed and evaluated an exposure model for individuals (EMI), which predicts five tiers of individual-level exposure metric...

  17. A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP)

    EPA Science Inventory

    The Pilot Study of Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) investigated the aggregate exposures of 257 preschool children and their primary adult caregivers to pollutants commonly detected in their everyday environments. ...

  18. A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP)

    EPA Science Inventory

    The Pilot Study of Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) investigated the aggregate exposures of 257 preschool children and their primary adult caregivers to pollutants commonly detected in their everyday environments. ...

  19. "Non-destructive" dimensional metrology of EUV resist gratings (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kline, R. Joseph; Sunday, Daniel F.; Windover, Donald; Kulmala, Tero S.; Ekinci, Yasin

    2017-03-01

    New critical dimension metrology methods such as critical dimension small angle X-ray scattering (CDSAXS) are being developed to meet the measurement challenges of next generation devices. Two key requirements for any new CD metrology method are non-destructiveness and the measurement speed. We will report on a study of beam damage and scattering strength of two model photoresist systems, HSQ and PMMA. We also will report on the status and initial results from NIST's upgraded lab CDSAXS system. 50 nm pitch line gratings were fabricated in HSQ and PMMA films using EUV interference lithography at the Swiss Light Source. The lines were about 30 nm tall and 20-30 nm wide. The 17 keV CDSAXS exposure time was varied from 0.1 s to 60 s to determine the minimum X-ray exposure required to obtain a satisfactory fit. Normal incident measurements separated by a blanket X-ray exposure were repeated to measure the decrease in scattering intensity with X-ray dose. The PMMA scattering signal was found to decrease by about 80 % before stabilizing at around 15 % of the original scattering intensity. The HSQ scattering signal decreased much less and stabilized at about 80 % of the original scattering intensity. We also conducted a series of variable-angle CDSAXS measurements as a function of blanket X-ray exposure to determine how the shape of the photoresist lines changed during X-ray exposure. For PMMA, we found the line width to remain constant and the line height to decrease from 25 nm to 10 nm during the exposure series. The exposures that damaged the samples corresponded to several hours of exposure to the synchrotron beam in a 100 µm spot and were much longer than what was required to characterize the line gratings. Smaller targets result in a larger dose and could potentially damage the resist in the time required to make a CDSAXS measurement. The large differences in beam damage between PMMA and HSQ show that resist damage from CDSAXS will depend on the particular resist

  20. Mapping Exposure to Multi-Pollutants Using Environmental Biomonitors-A Multi-Exposure Index.

    PubMed

    Serrano, Helena C; Köbel, Melanie; Palma-Oliveira, José; Pinho, Pedro; Branquinho, Cristina

    2017-06-01

    Atmosphere is a major pathway for transport and deposition of pollutants in the environment. In industrial areas, organic compounds are released or formed as by-products, such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F's). Inorganic chemical elements, including lead and arsenic, are also part of the pollutants mixture, and even in low concentrations may potentially be toxic and carcinogenic. However, assessing the spatial pattern of their deposition is difficult due to high spatial and temporal heterogeneity. Lichens have been used as biomonitors of atmospheric deposition, because these organisms encompass greater spatial detail than air monitoring stations and provide an integration of overall pollution. Based upon the ability of lichens to concentrate pollutants such as PCDD/F and chemical elements, the main objectives of this study were to develop a new semi-quantitative multi-pollutant toxicity exposure index (TEQ-like), derived from risk estimates, in an attempt to correlate several atmospheric pollutants to human exposure levels. The actual pollutant concentrations were measured in the environment, from biomonitors (organisms that integrate multi-pollutants), enabling interpolation and mapping of contaminant deposition within the region. Thus, the TEQ-like index provides a spatial representation not from absolute accumulation of the different pollutants, but from the accumulation weighted by their relative risk. The assessment of environmental human exposure to multi-pollutants through atmospheric deposition may be applied to industries to improve mitigation processes or to health stakeholders to target populations for a comprehensive risk assessment, epidemiological studies, and health recommendations.

  1. Socioeconomic Disparities and Air Pollution Exposure: A Global Review

    PubMed Central

    Hsia, Charlene; O’Neill, Marie S.

    2015-01-01

    The existing reviews and meta-analyses addressing unequal exposure of environmental hazards on certain populations have focused on several environmental pollutants or on the siting of hazardous facilities. This review updates and contributes to the environmental inequality literature by focusing on ambient criteria air pollutants (including NOx), by evaluating studies related to inequality by socioeconomic status (as opposed to race/ethnicity) and by providing a more global perspective. Overall, most North American studies have shown that areas where low socioeconomic status (SES) communities dwell experience higher concentrations of criteria air pollutants, while European research has been mixed. Research from Asia, Africa and other parts of the world has shown a general trend similar to that of North America, but research in these parts of the world is limited. PMID:26381684

  2. Socioeconomic Disparities and Air Pollution Exposure: a Global Review.

    PubMed

    Hajat, Anjum; Hsia, Charlene; O'Neill, Marie S

    2015-12-01

    The existing reviews and meta-analyses addressing unequal exposure of environmental hazards on certain populations have focused on several environmental pollutants or on the siting of hazardous facilities. This review updates and contributes to the environmental inequality literature by focusing on ambient criteria air pollutants (including NOx), by evaluating studies related to inequality by socioeconomic status (as opposed to race/ethnicity) and by providing a more global perspective. Overall, most North American studies have shown that areas where low-socioeconomic-status (SES) communities dwell experience higher concentrations of criteria air pollutants, while European research has been mixed. Research from Asia, Africa, and other parts of the world has shown a general trend similar to that of North America, but research in these parts of the world is limited.

  3. Commuter exposure to aerosol pollution on public transport in Singapore

    NASA Astrophysics Data System (ADS)

    Tan, S.; Velasco, E.; Roth, M.; Norford, L.

    2013-12-01

    Personal exposure to aerosol pollutants in the transport microenvironment of Singapore has not been well documented. Studies from many cities suggest that brief periods of exposure to high concentrations of airborne pollutants may have significant health impacts. Thus, a large proportion of aerosol exposure may be experienced during daily commuting trips due to the proximity to traffic. A better understanding of the variability across transport modes is therefore needed to design transport policies that minimize commuters' exposure. In light of this, personal exposure measurements of PM10 and PM2.5, particle number (PN), black carbon (BC), carbon monoxide (CO), particle-bound polycyclic aromatic hydrocarbons (pPAH), and active surface area (SA) were conducted on a selected route in downtown Singapore. Portable and real-time monitoring instruments were carried onto three different modes of public transport (bus, taxi, subway) and by foot. Simultaneous measurements were taken at a nearby park to capture the background concentrations. Large variability was observed amongst the various transport modes investigated. For example, the particle number concentration was on average 1.5, 1.6, 0.8, and 2.2 times higher inside buses, taxis, subway and by foot, respectively, than at the background site. Based on the results, it is possible to come up with a ranking of the 'cleanest' transport mode for Singapore.

  4. Video filming and pollution measurement as a teaching aid in reducing exposure to airborne pollutants.

    PubMed

    Rosén, G; Andersson, I M

    1989-01-01

    A method called PIMEX has been developed for investigation of the causes of exposure to airborne pollutants at workplaces. The method involves measurement of the subject's exposure with a personal, direct-reading instrument. The sampling signal is transmitted by telemetry to a special video mixer. A video camera is also connected to the video mixer. The camera is used for filming the subject. The video mixer's output signal is fed to a monitor which continuously shows how the subject works and how exposure varies. The method has been used for producing two films on the causes of exposure to solvent and effective measures for reducing exposure: one deals with screen printing and the other with surface treatment at wood-processing plants. The films have been shown at a large number of workplaces at discussions about workplace conditions, proving useful tools in efforts to reduce workplace risks and giving rise to concrete measures and increased interest in the workplace environment.

  5. Method and Apparatus for Non-Destructive Evaluation of Materials

    NASA Technical Reports Server (NTRS)

    Goldfine, Neil J. (Inventor); Washabaugh, Andrew P. (Inventor); Lyons, Robert (Inventor); Thomas, Zachary (Inventor); Jablonski, David A. (Inventor); Martin, Christopher (Inventor)

    2015-01-01

    Methods and apparatus for characterizing composite materials for manufacturing quality assurance (QA), periodic inspection during the useful life, or for forensic analysis/material testing. System are provided that relate eddy-current sensor responses to the fiber layup of a composite structure, the presence of impact damage on a composite structure with or without a metal liner, volumetric stress within the composite, fiber tow density, and other NDE inspection requirements. Also provided are systems that determine electromagnetic material properties and material dimensions of composite materials from capacitive sensor inspection measurements. These properties are related to the presence of buried defects in non-conductive composite materials, moisture ingress, aging of the material due to service or environmental/thermal exposure, or changes in manufacturing quality.

  6. Non-Destructive Lichen Biomass Estimation in Northwestern Alaska: A Comparison of Methods

    PubMed Central

    Rosso, Abbey; Neitlich, Peter; Smith, Robert J.

    2014-01-01

    Terrestrial lichen biomass is an important indicator of forage availability for caribou in northern regions, and can indicate vegetation shifts due to climate change, air pollution or changes in vascular plant community structure. Techniques for estimating lichen biomass have traditionally required destructive harvesting that is painstaking and impractical, so we developed models to estimate biomass from relatively simple cover and height measurements. We measured cover and height of forage lichens (including single-taxon and multi-taxa “community” samples, n = 144) at 73 sites on the Seward Peninsula of northwestern Alaska, and harvested lichen biomass from the same plots. We assessed biomass-to-volume relationships using zero-intercept regressions, and compared differences among two non-destructive cover estimation methods (ocular vs. point count), among four landcover types in two ecoregions, and among single-taxon vs. multi-taxa samples. Additionally, we explored the feasibility of using lichen height (instead of volume) as a predictor of stand-level biomass. Although lichen taxa exhibited unique biomass and bulk density responses that varied significantly by growth form, we found that single-taxon sampling consistently under-estimated true biomass and was constrained by the need for taxonomic experts. We also found that the point count method provided little to no improvement over ocular methods, despite increased effort. Estimated biomass of lichen-dominated communities (mean lichen cover: 84.9±1.4%) using multi-taxa, ocular methods differed only nominally among landcover types within ecoregions (range: 822 to 1418 g m−2). Height alone was a poor predictor of lichen biomass and should always be weighted by cover abundance. We conclude that the multi-taxa (whole-community) approach, when paired with ocular estimates, is the most reasonable and practical method for estimating lichen biomass at landscape scales in northwest Alaska. PMID:25079228

  7. Non-destructive lichen biomass estimation in northwestern Alaska: a comparison of methods.

    PubMed

    Rosso, Abbey; Neitlich, Peter; Smith, Robert J

    2014-01-01

    Terrestrial lichen biomass is an important indicator of forage availability for caribou in northern regions, and can indicate vegetation shifts due to climate change, air pollution or changes in vascular plant community structure. Techniques for estimating lichen biomass have traditionally required destructive harvesting that is painstaking and impractical, so we developed models to estimate biomass from relatively simple cover and height measurements. We measured cover and height of forage lichens (including single-taxon and multi-taxa "community" samples, n = 144) at 73 sites on the Seward Peninsula of northwestern Alaska, and harvested lichen biomass from the same plots. We assessed biomass-to-volume relationships using zero-intercept regressions, and compared differences among two non-destructive cover estimation methods (ocular vs. point count), among four landcover types in two ecoregions, and among single-taxon vs. multi-taxa samples. Additionally, we explored the feasibility of using lichen height (instead of volume) as a predictor of stand-level biomass. Although lichen taxa exhibited unique biomass and bulk density responses that varied significantly by growth form, we found that single-taxon sampling consistently under-estimated true biomass and was constrained by the need for taxonomic experts. We also found that the point count method provided little to no improvement over ocular methods, despite increased effort. Estimated biomass of lichen-dominated communities (mean lichen cover: 84.9±1.4%) using multi-taxa, ocular methods differed only nominally among landcover types within ecoregions (range: 822 to 1418 g m-2). Height alone was a poor predictor of lichen biomass and should always be weighted by cover abundance. We conclude that the multi-taxa (whole-community) approach, when paired with ocular estimates, is the most reasonable and practical method for estimating lichen biomass at landscape scales in northwest Alaska.

  8. Multi-pollutant exposures in an asthmatic cohort

    NASA Astrophysics Data System (ADS)

    Williams, Ron; Rappold, Ana G.; Case, Martin; Schmitt, Mike; Stone, Susan; Jones, Paul; Thornburg, Jonathan; Devlin, Robert B.

    2012-12-01

    An investigation of personal fine and coarse particulate matter (PM2.5, PM10-2.5), nitrogen dioxide (NO2), and ozone (O3) exposures was conducted with an adult asthmatic cohort as part of the U.S. Environmental Protection Agency's Moderate and Severe Asthmatics and their Environment Study (MASAES). The overall goal of the MASAES was to determine the association of particulate matter on the degree of resulting lung inflammation, with those having severe asthma hypothesized to be more highly susceptible to such outcomes. The primary exposure objective was to determine the spatial (personal versus ambient) and temporal relationships associated with the aforementioned air pollutants and establish the precision of a new dual PM2.5, PM10-2.5 monitor (CPEM) for personal exposure monitoring. A total of 16 non-smoking adults of various asthma severities were monitored over the course of a 14 month period during 2008-2009. Participants were monitored for 24 continuous hours each monitoring day with a maximum of five events per participant. Median personal PM2.5 and PM10-2.5 exposures were 16.5 and 10.1 μg m-3, respectively. Daily ambient mass concentrations accounted for less than 1% of the observed variability in personal PM2.5 or PM10-2.5 exposures. Duplicate personal measures yielded R2 values of 0.92 PM2.5 and 0.77 PM10-2.5, respectively. Maximum daily personal exposures of 17.0 ppb NO2 and 21.7 ppb O3 occurred with respective mean exposures of 5.8 and 3.4 ppb. Ambient NO2 and O3 measures were observed to be poorly associated with personal exposures (R2 < 0.08) when viewed independent of the participant. The poor correlation between personal and ambient concentrations of PM as well as the various gaseous copollutants indicates the complexity of the multi-pollutant environment and the impact of non-ambient sources on these pollutants relative to total personal exposures.

  9. Air pollution exposure: An activity pattern approach for active transportation

    NASA Astrophysics Data System (ADS)

    Adams, Matthew D.; Yiannakoulias, Nikolaos; Kanaroglou, Pavlos S.

    2016-09-01

    In this paper, we demonstrate the calculation of personal air pollution exposure during trips made by active transportation using activity patterns without personal monitors. We calculate exposure as the inhaled dose of particulate matter 2.5 μg or smaller. Two modes of active transportation are compared, and they include cycling and walking. Ambient conditions are calculated by combining mobile and stationary monitoring data in an artificial neural network space-time model. The model uses a land use regression framework and has a prediction accuracy of R2 = 0.78. Exposure is calculated at 10 m or shorter intervals during the trips using inhalation rates associated with both modes. The trips are children's routes between home and school. The average dose during morning cycling trips was 2.17 μg, during morning walking trips was 3.19 μg, during afternoon cycling trips was 2.19 μg and during afternoon walking trips was 3.23 μg. The cycling trip dose was significantly lower than the walking trip dose. The air pollution exposure during walking or cycling trips could not be strongly predicted by either the school or household ambient conditions, either individually or in combination. Multiple linear regression models regressing both the household and school ambient conditions against the dose were only able to account for, at most, six percent of the variance in the exposure. This paper demonstrates that incorporating activity patterns when calculating exposure can improve the estimate of exposure compared to its calculation from ambient conditions.

  10. Air pollution exposure, cause-specific deaths and hospitalizations in a highly polluted Italian region.

    PubMed

    Carugno, Michele; Consonni, Dario; Randi, Giorgia; Catelan, Dolores; Grisotto, Laura; Bertazzi, Pier Alberto; Biggeri, Annibale; Baccini, Michela

    2016-05-01

    The Lombardy region in northern Italy ranks among the most air polluted areas of Europe. Previous studies showed air pollution short-term effects on all-cause mortality. We examine here the effects of particulate matter with aerodynamic diameter ≤10µm (PM10) and nitrogen dioxide (NO2) exposure on deaths and hospitalizations from specific causes, including cardiac, cerebrovascular and respiratory diseases. We considered air pollution, mortality and hospitalization data for a non-opportunistic sample of 18 highly polluted and most densely populated areas of the region in the years 2003-2006. We obtained area-specific effect estimates for PM10 and NO2 from a Poisson regression model on the daily number of total deaths or cause-specific hospitalizations and then combined them in a Bayesian random-effects meta-analysis. For cause-specific mortality, we applied a case-crossover analysis. Age- and season-specific analyses were also performed. Effect estimates were expressed as percent variation in mortality or hospitalizations associated with a 10µg/m(3) increase in PM10 or NO2 concentration. Natural mortality was positively associated with both pollutants (0.30%, 90% Credibility Interval [CrI]: -0.31; 0.78 for PM10; 0.70%, 90%CrI: 0.10; 1.27 for NO2). Cardiovascular deaths showed a higher percent variation in association with NO2 (1.12%, 90% Confidence Interval [CI]: 0.14; 2.11), while the percent variation for respiratory mortality was highest in association with PM10 (1.64%, 90%CI: 0.35; 2.93). The effect of both pollutants was more evident in the summer season. Air pollution was also associated to hospitalizations, the highest variations being 0.77% (90%CrI: 0.22; 1.43) for PM10 and respiratory diseases, and 1.70% (90%CrI: 0.39; 2.84) for NO2 and cerebrovascular diseases. The effect of PM10 on respiratory hospital admissions appeared to increase with age. For both pollutants, effects on cerebrovascular hospitalizations were more evident in subjects aged less than

  11. Prediction of Eggshell Ultrastructure via Some Non-destructive and Destructive Measurements in Fayoumi Breed

    PubMed Central

    Radwan, Lamiaa M.; Galal, A.; Shemeis, A. R.

    2015-01-01

    Possibilities of predicting eggshell ultrastructure from direct non-destructive and destructive measurements were examined using 120 Fayoumi eggs collected from the flock at 45 weeks of age. The non-destructive measurements included weight, length and width of the egg. The destructive measurements were breaking strength and shell thickness. The eggshell ultrastructure traits involved the total thickness of eggshell layer, thickness of palisade layer, cone layer and total score. Prediction of total thickness of eggshell layer based on non-destructive measurements individually or simultaneously was not possible (R2 = 0.01 to 0.16). The destructive measurements were far more accurate than the non-destructive in predicting total thickness of eggshell layer. Prediction based on breaking strength alone was more accurate (R2 = 0.85) than that based on shell thickness alone (R2 = 0.72). Adding shell thickness to breaking strength (the best predictor) increased the accuracy of prediction by 5%. The results obtained indicated that both non-destructive and destructive measurements were not useful in predicting the cone layer (R2 not exceeded 18%). The maximum accuracy of prediction of total score (R2 = 0.48) was obtained from prediction based on breaking strength alone. Combining shell thicknesses and breaking strength into one equation was no help in improving the accuracy of prediction. PMID:26104404

  12. Prediction of Eggshell Ultrastructure via Some Non-destructive and Destructive Measurements in Fayoumi Breed.

    PubMed

    Radwan, Lamiaa M; Galal, A; Shemeis, A R

    2015-07-01

    Possibilities of predicting eggshell ultrastructure from direct non-destructive and destructive measurements were examined using 120 Fayoumi eggs collected from the flock at 45 weeks of age. The non-destructive measurements included weight, length and width of the egg. The destructive measurements were breaking strength and shell thickness. The eggshell ultrastructure traits involved the total thickness of eggshell layer, thickness of palisade layer, cone layer and total score. Prediction of total thickness of eggshell layer based on non-destructive measurements individually or simultaneously was not possible (R(2) = 0.01 to 0.16). The destructive measurements were far more accurate than the non-destructive in predicting total thickness of eggshell layer. Prediction based on breaking strength alone was more accurate (R(2) = 0.85) than that based on shell thickness alone (R(2) = 0.72). Adding shell thickness to breaking strength (the best predictor) increased the accuracy of prediction by 5%. The results obtained indicated that both non-destructive and destructive measurements were not useful in predicting the cone layer (R(2) not exceeded 18%). The maximum accuracy of prediction of total score (R(2) = 0.48) was obtained from prediction based on breaking strength alone. Combining shell thicknesses and breaking strength into one equation was no help in improving the accuracy of prediction.

  13. Improving estimates of air pollution exposure through ubiquitous sensing technologies

    PubMed Central

    de Nazelle, Audrey; Seto, Edmund; Donaire-Gonzalez, David; Mendez, Michelle; Matamala, Jaume; Nieuwenhuijsen, Mark J; Jerrett, Michael

    2013-01-01

    Traditional methods of exposure assessment in epidemiological studies often fail to integrate important information on activity patterns, which may lead to bias, loss of statistical power or both in health effects estimates. Novel sensing technologies integrated with mobile phones offer potential to reduce exposure measurement error. We sought to demonstrate the usability and relevance of the CalFit smartphone technology to track person-level time, geographic location, and physical activity patterns for improved air pollution exposure assessment. We deployed CalFit-equipped smartphones in a free living-population of 36 subjects in Barcelona, Spain. Information obtained on physical activity and geographic location was linked to space-time air pollution mapping. For instance, we found on average travel activities accounted for 6% of people’s time and 24% of their daily inhaled NO2. Due to the large number of mobile phone users, this technology potentially provides an unobtrusive means of collecting epidemiologic exposure data at low cost. PMID:23416743

  14. Ecological and spatial factors drive intra- and interspecific variation in exposure of subarctic predatory bird nestlings to persistent organic pollutants.

    PubMed

    Eulaers, Igor; Jaspers, Veerle L B; Bustnes, Jan O; Covaci, Adrian; Johnsen, Trond V; Halley, Duncan J; Moum, Truls; Ims, Rolf A; Hanssen, Sveinn A; Erikstad, Kjell E; Herzke, Dorte; Sonne, Christian; Ballesteros, Manuel; Pinxten, Rianne; Eens, Marcel

    2013-07-01

    contamination). In conclusion, the combined analysis of POPs and stable isotopes in body feathers from fully-grown nestlings has identified ecological and spatial factors that may drive POP exposure over the larger part of the nestling stage. This methodological approach further promotes the promising use of nestling predatory bird body feathers as a non-destructive sampling strategy to integrate various toxicological and ecological proxies.

  15. Race, socioeconomic status, and air pollution exposure in North Carolina.

    PubMed

    Gray, Simone C; Edwards, Sharon E; Miranda, Marie Lynn

    2013-10-01

    Although studies suggest that exposure to pollutants is associated with race/ethnicity and socio-economic status (SES), many studies are limited to the geographic regions where monitoring stations are located. This study uses modeled predictive surfaces to examine the relationship between air pollution exposure, race/ethnicity, and measures of SES across the entire State of North Carolina. The daily predictions of particulate matter <2.5 µm in aerodynamic diameter (PM2.5) and ozone (O3) were determined using a spatial model that fused data from two sources: point air monitoring data and gridded numerical output. These daily predicted pollution levels for 2002 were linked with Census data. We examine the relationship between the census-tract level predicted concentration measures, SES, and racial composition. SES and race/ethnicity were related to predicted concentrations of both PM2.5 and O3 for census tracts in North Carolina. Lower SES and higher proportion minority population were associated with higher levels of PM2.5. An interquartile range (IQR) increase of median household income reduced the predicted average PM2.5 level by 0.10 µg/m3. The opposite relationship was true for O3. An IQR increase of median household income increased the predicted average O3 measure by 0.11 ppb. The analyses demonstrate that SES and race/ethnicity are related to predicted estimates of PM2.5 and O3 for census tracts in North Carolina. These findings offer a baseline for future exposure modeling work involving SES and air pollution for the entire state and not just among the populations residing near monitoring networks. Published by Elsevier Inc.

  16. Proximity analysis of air pollution exposure and its potential risk.

    PubMed

    Thepanondh, Sarawut; Toruksa, Wassana

    2011-05-01

    Proximity analysis and spatial variability of the ambient nitrogen dioxide (NO(2)) concentration in Rayong province, Thailand, were analyzed using geostatistics and spatial modeling techniques. Annual concentrations of nitrogen dioxide were predicted and spatially interpolated using various interpolation techniques (i.e. kriging, IDW and spline). Sensitivity analysis was carried out to assure the accuracy of the predicted results. The GIS-based exposure map was simulated and was assisted to identify high exposure areas. A health risk warning system was set for "action" (exceeds 100% of the annual average NO(2) guideline), for "alert" (between 66-100% of the annual average NO(2) guideline) and for "some concern" (between 33-66% of the annual average NO(2) guideline). Although no areas were exposed to an action level, many locations in the study area could have levels of "some concern". Potential risk to the population was analyzed by spatial interpolation of the nitrogen dioxide concentration with population data. The result indicated the number of people exposed to air pollution, as well as the areas which have a high risk to air pollution. About 88.3% of the total population in the study area live in areas where levels of air pollution are designated as being in the "some concern" zone. About 6.7% of the registered population have their residence in an area where action should be taken for air quality management. The study demonstrates the application of GIS-based prediction for the evaluation of exposure mapping, in order to determine the spatial extent and frequency of areas where pollution levels exceed target values, and their potential health impacts.

  17. Pediatric Conjunctivitis and Air Pollution Exposure: A Prospective Observational Study.

    PubMed

    Nucci, Paolo; Sacchi, Matteo; Pichi, Francesco; Allegri, Pia; Serafino, Massimiliano; Dello Strologo, Marika; De Cillà, Stefano; Villani, Edoardo

    2017-01-01

    To investigate, in pediatric patients, the rate and clinical features of unspecific conjunctivitis of unknown origin (UCUO) and to evaluate their relationship with air pollution. From January to December 2013, we consecutively screened all of the patients referred for symptomatic ocular surface inflammation. Inclusion criteria for this study were age<14, diagnosis of conjunctivitis, residence in the Lombardia region. UCUO was defined as conjunctivitis of unknown etiology, not clearly due to infection or allergy. Based on addresses of residence and sites of 73 automatic air pollution monitoring stations (locations and mean annual particulate matter (PM) 10 and 2.5 concentrations were provided by the Regional Environmental Protection Agency (ARPA) Lombardia), each patient was paired with a value of exposure to PM. Relationship between UCUO and PM exposure was investigated. A total of 132 of 251 screened children were included in this study. UCUO was diagnosed in 48/132 patients. The most common symptoms and signs in UCUO children were foreign body sensation (37/48) and conjunctival hyperemia (45/48), respectively. PM10 exposure value was significantly higher in UCUO (33.5±5.4µg/m3) compared to other groups (P<0.001, ANOVA). UCUO/total conjunctivitis ratio was significantly higher in residents in areas with more than 75 (Q3) days/year exceeding 50µg/m3 (EU legal limit) compared to areas with less than 45 (Q1) exceedances/year: 24/39: 61% vs 8/35: 23%; P>0.001, Chi-square test. Our data suggest a relationship between UCUO and air pollution. This form of conjunctivitis is not rare in pediatric patients and may be the most frequent in most polluted areas.

  18. Estimates of health risk from exposure to radioactive pollutants

    SciTech Connect

    Sullivan, R.E.; Nelson, N.S.; Ellett, W.H.; Dunning, D.E. Jr.; Leggett, R.W.; Yalcintas, M.G.; Eckerman, K.F.

    1981-11-01

    A dosimetric and health effects analysis has been performed for the Office of Radiation Programs of the Environmental Protection Agency (EPA) to assess potential hazards from radioactive pollutants. Contemporary dosimetric methods were used to obtain estimates of dose rates to reference organs from internal exposures due to either inhalation of contaminated air or ingestion of contaminated food, or from external exposures due to either immersion in contaminated air or proximity to contaminated ground surfaces. These dose rates were then used to estimate the number of premature cancer deaths arising from such exposures and the corresponding number of years of life lost in a cohort of 100,000 persons, all simultaneously liveborn and all going through life with the same risks of dying from competing causes. The risk of dying from a competing cause for a given year was taken to be the probability of dying from all causes as given in a recent actuarial life table for the total US population.

  19. Maternal Exposure to Air Pollution and Birth Outcomes

    PubMed Central

    Malmqvist, Ebba; Rignell-Hydbom, Anna; Tinnerberg, Håkan; Björk, Jonas; Stroh, Emilie; Jakobsson, Kristina; Rittner, Ralf; Rylander, Lars

    2011-01-01

    Background The knowledge about air pollution effects on birth weight, prematurity, and small for gestational age (SGA) in low-exposure areas is insufficient. Objectives The aim of this birth cohort study was to investigate whether low-level exposure to air pollution was associated with prematurity and fetal growth and whether there are sex-specific effects. Method We combined high-quality registry information on 81,110 births with individually modeled exposure data at residence for nitrogen oxides (NOx) and proximity to roads with differing traffic density. The data were analyzed by logistic and linear regression with and without potential confounders. Results We observed an increased risk for babies being SGA when we compared highest and lowest NOx quartiles, adjusting for maternal age, smoking, sex, and year of birth. After additional adjustment for maternal country of origin and parity (which were highly intercorrelated), the increase was no longer statistically significant. However, in subgroup analyses when we compared highest and lowest NOx quartiles we still observed an increased risk for SGA for girls [odds ratio (OR) = 1.12; 95% confidence interval (CI), 1.01–1.24); we also observed increased risk among mothers who had not changed residency during pregnancy (OR = 1.09; 95% CI, 1.01–1.18). The confounders with the greatest impact on SGA were parity and country of origin. Concerning prematurity, the prevalence was lower in the three higher NOx exposure quartiles compared with the lowest category. Conclusion For future studies on air pollution effects on birth outcomes, careful control of confounding is crucial. PMID:21212043

  20. Evaluation of noise pollution level based upon community exposure and response data

    NASA Technical Reports Server (NTRS)

    Edmiston, R. D.

    1972-01-01

    The results and procedures are reported from an evaluation of noise pollution level as a predictor of annoyance, based on aircraft noise exposure and community response data. The measures of noise exposure presented include composite noise rating, noise exposure forecast, noise and number index. A proposed measure as a universal noise exposure measure for noise pollution level (L sub NP) is discussed.

  1. Air pollution in moderately polluted urban areas: How does the definition of "neighborhood" impact exposure assessment?

    PubMed

    Tenailleau, Quentin M; Mauny, Frédéric; Joly, Daniel; François, Stéphane; Bernard, Nadine

    2015-11-01

    Environmental health studies commonly quantify subjects' pollution exposure in their neighborhood. How this neighborhood is defined can vary, however, leading to different approaches to quantification whose impacts on exposure levels remain unclear. We explore the relationship between neighborhood definition and exposure assessment. NO2, benzene, PM10 and PM2.5 exposure estimates were computed in the vicinity of 10,825 buildings using twelve exposure assessment techniques reflecting different definitions of "neighborhood". At the city scale, its definition does not significantly influence exposure estimates. It does impact levels at the building scale, however: at least a quarter of the buildings' exposure estimates for a 400 m buffer differ from the estimated 50 m buffer value (±1.0 μg/m(3) for NO2, PM10 and PM2.5; and ±0.05 μg/m(3) for benzene). This variation is significantly related to the definition of neighborhood. It is vitally important for investigators to understand the impact of chosen assessment techniques on exposure estimates. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Non-Destructive Testing A Developing Tool in Science and Engineering

    SciTech Connect

    Lin, Lianshan

    2013-01-01

    Non-destructive testing (NDT), sometimes also known as non-destructive inspection (NDI) or non-destructive examination (NDE), has been applied to solve a wide range of science and industry problems including construction, aerospace, nuclear engineering, manufacturing, space exploration, art objects, forensic studies, biological and medical fields, etc. Without any permanent changing or alteration of testing objects, NDT methods provide great advantages such as increased testing reliability, efficiency, and safety, as well as reduced time and cost. Since the second half of the 20th century, NDT technology has seen significant growth. Depending on the physical properties being measured, NDT techniques can be classified into several branches. This article will provide a brief overview of commonly used NDT methods and their up-to-date progresses including optical examination, radiography, acoustic emission, ultrasonic testing and eddy current testing. For extended reviews on many presently used NDT methods, please refer to articles by Mullins [1, 2].

  3. Non-destructive testing of composite materials using terahertz time-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Yakovlev, Egor V.; Zaytsev, Kirill I.; Chernomyrdin, Nikita V.; Gavdush, Arsenii A.; Zotov, Arsen K.; Nikonovich, Maxim Y.; Yurchenko, Stanislav O.

    2016-04-01

    Development of novel methods for non-destructive evaluation of composite materials (CMs) at manufacturing and operational stages remains challenging problem of applied physics, optics and material science. In this paper, we have considered the ability to use the terahertz (THz) time-domain spectroscopy (TDS) for non-destructive evaluation of CMs. By combining the TDS technique with appropriate methods of solving the inverse ill-posed problems, we have shown that TDS could be applied for CM testing. At first, we have demonstrated that TDS could be used to control the polymerization process and, as a consequence, the CM binder curing. Secondary, we have shown the ability to detect the internal defects (non-impregnated voids) inside the CMs via the TDS-based THz time-of-flight tomography. Thereby, the results of our study allow highlighting the prospective of non-destructive evaluation of CMs using the TDS.

  4. Assessment of exposure to mixture pollutants in Mexican indigenous children.

    PubMed

    Flores-Ramírez, R; Pérez-Vázquez, F J; Cilia-López, V G; Zuki-Orozco, B A; Carrizales, L; Batres-Esquivel, L E; Palacios-Ramírez, A; Díaz-Barriga, F

    2016-05-01

    The aim of the present work was to complete an exposure assessment in three Mexican indigenous communities using the community-based health risk assessment, which is the first step in the CHILD framework. We used 1-hydroxypyrene (1-OHP) as an exposure biomarker to polycyclic aromatic hydrocarbons (PAHs) and trans, trans-muconic acid (t,t-MA) as an exposure biomarker to benzene, persistent organic pollutants (POPs), lead, manganese, arsenic, and fluoride. Anthropometric measurements were also taken. In these communities, high percentages of children with chronic malnutrition were found (28 to 49 %) based on their weight and age. All communities showed a high percentage of children with detectable levels of four or more compounds (70 to 82 %). Additionally, our results showed that in indigenous communities, children are exposed to elevated levels of certain environmental pollutants, including manganese with 17.6, 16.8, and 7.3 μg/L from SMP, TOC, and CUA, respectively. Lead and HCB levels were similar in the indigenous communities (2.5, 3.1, and 4.2 μg/dL and 2.5, 3.1, and 3.7 ng/mL, respectively). 1-OHP and t,t-MA levels were higher in TOC (0.8 μmol/mol of creatinine, 476 μg/g of creatinine, respectively) when compared with SMP (0.1 μmol/mol of creatinine, 215.5 μg/g of creatinine, respectively) and CUA (0.1 μmol/mol of creatinine, 185.2 μg/g of creatinine, respectively). DDE levels were 30.7, 26.9, and 9.6 ng/mL in CUA, SMP, and TOC, respectively. The strength of this study is that it assesses exposure to pollutants with indications for the resultant risk before an intervention is made by the CHILD program to manage this risk in the indigenous communities. Considering the large number of people, especially children, exposed to multiple pollutants, it is important to design effective intervention programs that reduce exposure and the resultant risk in the numerous indigenous communities in Mexico.

  5. Comparative analysis of non-destructive methods to control fissile materials in large-size containers

    NASA Astrophysics Data System (ADS)

    Batyaev, V. F.; Sklyarov, S. V.

    2017-09-01

    The analysis of various non-destructive methods to control fissile materials (FM) in large-size containers filled with radioactive waste (RAW) has been carried out. The difficulty of applying passive gamma-neutron monitoring FM in large containers filled with concreted RAW is shown. Selection of an active non-destructive assay technique depends on the container contents; and in case of a concrete or iron matrix with very low activity and low activity RAW the neutron radiation method appears to be more preferable as compared with the photonuclear one. Note to the reader: the pdf file has been changed on September 22, 2017.

  6. Edward's sword? - A non-destructive study of a medieval king's sword

    SciTech Connect

    Segebade, Chr.

    2013-04-19

    Non-destructive and instrumental methods including photon activation analysis were applied in an examination of an ancient sword. It was tried to find indication of forgery or, if authentic, any later processing and alteration. Metal components of the hilt and the blade were analysed by instrumental photon activation. Non-destructive metallurgical studies (hardness measurements, microscopic microstructure analysis) are briefly described, too. The results of these investigations did not yield indication of non-authenticity. This stood in agreement with the results of stylistic and scientific studies by weapon experts.

  7. X-ray phase scanning setup for non-destructive testing using Talbot-Lau interferometer

    NASA Astrophysics Data System (ADS)

    Bachche, S.; Nonoguchi, M.; Kato, K.; Kageyama, M.; Koike, T.; Kuribayashi, M.; Momose, A.

    2016-09-01

    X-ray grating interferometry has a great potential for X-ray phase imaging over conventional X-ray absorption imaging which does not provide significant contrast for weakly absorbing objects and soft biological tissues. X-ray Talbot and Talbot-Lau interferometers which are composed of transmission gratings and measure the differential X-ray phase shifts have gained popularity because they operate with polychromatic beams. In X-ray radiography, especially for nondestructive testing in industrial applications, the feasibility of continuous sample scanning is not yet completely revealed. A scanning setup is frequently advantageous when compared to a direct 2D static image acquisition in terms of field of view, exposure time, illuminating radiation, etc. This paper demonstrates an efficient scanning setup for grating-based Xray phase imaging using laboratory-based X-ray source. An apparatus consisting of an X-ray source that emits X-rays vertically, optical gratings and a photon-counting detector was used with which continuously moving objects across the field of view as that of conveyor belt system can be imaged. The imaging performance of phase scanner was tested by scanning a long continuous moving sample at a speed of 5 mm/s and absorption, differential-phase and visibility images were generated by processing non-uniform moire movie with our specially designed phase measurement algorithm. A brief discussion on the feasibility of phase scanner with scanning setup approach including X-ray phase imaging performance is reported. The successful results suggest a breakthrough for scanning objects those are moving continuously on conveyor belt system non-destructively using the scheme of X-ray phase imaging.

  8. Diabetes Incidence and Long-Term Exposure to Air Pollution

    PubMed Central

    Andersen, Zorana J.; Raaschou-Nielsen, Ole; Ketzel, Matthias; Jensen, Steen S.; Hvidberg, Martin; Loft, Steffen; Tjønneland, Anne; Overvad, Kim; Sørensen, Mette

    2012-01-01

    OBJECTIVE Animal and cross-sectional epidemiological studies suggest a link between air pollution and diabetes, whereas the limited prospective data show mixed results. We studied the association between long-term exposure to traffic-related air pollution and incidence of diabetes. RESEARCH DESIGN AND METHODS We followed 57,053 participants of the Danish Diet, Cancer, and Health cohort in the Danish National Diabetes Register between baseline (1993–1997) and 27 June 2006. We estimated the mean levels of nitrogen dioxide (NO2) at the residential addresses of the cohort participants since 1971 and modeled the association between NO2 and diabetes incidence with a Cox regression model, separately for two definitions of diabetes: all cases and a more strict definition where unconfirmed cases were excluded. RESULTS Over a mean follow-up of 9.7 years of 51,818 eligible subjects, there were 4,040 (7.8%) incident diabetes cases in total and 2,877 (5.5%) with confirmed diagnoses. Air pollution was not associated with all diabetes cases (hazard ratio 1.00 [95% CI 0.97–1.04] per interquartile range of 4.9 μg/m3 mean NO2 levels since 1971), but a borderline statistically significant association was detected with confirmed cases of diabetes (1.04 [1.00–1.08]). Among confirmed diabetes cases, effects were significantly enhanced in nonsmokers (1.12 [1.05–1.20]) and physically active people (1.10 [1.03–1.16]). CONCLUSIONS Long-term exposure to traffic-related air pollution may contribute to the development of diabetes, especially in individuals with a healthy lifestyle, nonsmokers, and physically active individuals. PMID:22074722

  9. Satellite-aided evaluation of population exposure to air pollution

    NASA Technical Reports Server (NTRS)

    Todd, W. J.; George, A. J., Jr.; Bryant, N. A.

    1979-01-01

    The evaluation of population exposure to air pollution through the computer processing of Landsat digital land use data, along with total suspended particulate estimates and population data by census tracts, is demonstrated. Digital image processing was employed to analyze simultaneously data from Landsat MSS bands 4 through 7 in order to extract land use and land cover information. The three data sets were spatially registered in a digital format, compatible with integrated computer processing, and cross-tabulated. A map illustrating relative air quality by 2-sq km cells for the residential population in the Portland, Oregon area is obtained.

  10. Satellite-aided evaluation of population exposure to air pollution

    NASA Technical Reports Server (NTRS)

    Todd, W. J.; George, A. J., Jr.; Bryant, N. A.

    1979-01-01

    The evaluation of population exposure to air pollution through the computer processing of Landsat digital land use data, along with total suspended particulate estimates and population data by census tracts, is demonstrated. Digital image processing was employed to analyze simultaneously data from Landsat MSS bands 4 through 7 in order to extract land use and land cover information. The three data sets were spatially registered in a digital format, compatible with integrated computer processing, and cross-tabulated. A map illustrating relative air quality by 2-sq km cells for the residential population in the Portland, Oregon area is obtained.

  11. Human nasal mucosal changes after exposure to urban pollution.

    PubMed Central

    Calderon-Garcidueñas, L; Rodriguez-Alcaraz, A; Garcia, R; Sanchez, G; Barragan, G; Camacho, R; Ramirez, L

    1994-01-01

    Millions of people worldwide are living in areas where ozone (O3) concentrations exceed health standards (an hourly average of 235 micrograms/m3/0.12 ppm, not to be exceeded more than once per year). Ozone induces acute nasal inflammatory responses and significant epithelial lesions in experimental animals and humans. To determine the nasal effects of a 15-day exposure to an urban polluted atmosphere with O3 as the main pollutant, we studied a population of healthy, young males newly arrived to southwest metropolitan Mexico City (SWMMC). The study included 49 non-smoking residents in an unpolluted port, Veracruz City; 14 subjects stayed in the port and served as controls, while 35 subjects traveled to SWMMC and had serial nasal lavages at different times after arriving in SWMMC. Subjects had exposures to ambient O3 an average of 10.2 hr/day, with a total cumulative O3 exposure of 10.644 ppm.hr. Nasal inflammatory responses, polymorphonuclear leukocyte PMN-CD11b surface expression, rhinoscopic changes, and respiratory symptoms were evaluated. Exposed subjects had massive nasal epithelial shedding and significant responses in PMN nasal influx (p < 0.00001) and in PMN-CD11b expression (p < 0.05). Cumulative O3 exposure correlated with respiratory symptoms, PMNs (rs = 0.2374, p < 0.01), and CD11b (rs = 0.3094, p < 0.01); 94% of exposed subjects experienced respiratory symptoms, and 97% left the city with an abnormal nasal mucosa by rhinoscopy. Nasal epithelial changes persisted 2 weeks after the exposed subjects returned to their nonpolluted environment. Exposure to an urban polluted atmosphere induces significant and persistent nasal epithelial alterations in healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 1. Figure 2. A Figure 2. B Figure 2. C Figure 2. D Figure 2. E Figure 2. F Figure 3. A Figure 3. B Figure 4. A Figure 4. B Figure 5. A Figure 5. B PMID:7713020

  12. Acute Air Pollution Exposure and Risk of Suicide Completion

    PubMed Central

    Bakian, Amanda V.; Huber, Rebekah S.; Coon, Hilary; Gray, Douglas; Wilson, Phillip; McMahon, William M.; Renshaw, Perry F.

    2015-01-01

    Research into environmental factors associated with suicide has historically focused on meteorological variables. Recently, a heightened risk of suicide related to short-term exposure to airborne particulate matter was reported. Here, we examined the associations between short-term exposure to nitrogen dioxide, particulate matter, and sulfur dioxide and completed suicide in Salt Lake County, Utah (n = 1,546) from 2000 to 2010. We used a time-stratified case-crossover design to estimate adjusted odds ratios for the relationship between suicide and exposure to air pollutants on the day of the suicide and during the days preceding the suicide. We observed maximum heightened odds of suicide associated with interquartile-range increases in nitrogen dioxide during cumulative lag 3 (average of the 3 days preceding suicide; odds ratio (OR) = 1.20, 95% confidence interval (CI): 1.04, 1.39) and fine particulate matter (diameter ≤2.5 μm) on lag day 2 (day 2 before suicide; OR = 1.05, 95% CI: 1.01, 1.10). Following stratification by season, an increased suicide risk was associated with exposure to nitrogen dioxide during the spring/fall transition period (OR = 1.35, 95% CI: 1.09, 1.66) and fine particulate matter in the spring (OR = 1.28, 95% CI: 1.01, 1.61) during cumulative lag 3. Findings of positive associations between air pollution and suicide appear to be consistent across study locations with vastly different meteorological, geographical, and cultural characteristics. PMID:25673816

  13. A spatially offset Raman spectroscopy method for non-destructive detection of gelatin-encapsulated powders

    USDA-ARS?s Scientific Manuscript database

    Non-destructive subsurface detection of encapsulated, coated, or seal-packaged foods and pharmaceuticals can help prevent distribution and consumption of counterfeit or hazardous products. This study used a Spatially Offset Raman Spectroscopy (SORS) method to detect and identify urea, ibuprofen, and...

  14. Non-destructive method for inward leakage detection of a plate evaporator

    NASA Astrophysics Data System (ADS)

    Hribernik, Ales

    2007-05-01

    A new non-destructive method was developed for the detection of refrigerant leakage at an evaporator's inflow. Nitrogen and oxygen gas were successively blown through the evaporator. A gas analyser was applied at the outflow of the evaporator and the oxygen concentration measured. It was possible to detect any leakage by investigating the oxygen concentration-time history diagram.

  15. Non-destructive digital imaging in poplar allows detailed analysis of adventitious rooting dynamics

    Treesearch

    R.J. Kodrzycki; R.B. Michaels; A.L. Friend; R.S. Zalesny; Ch.P. Mawata; D.W. McDonald

    2008-01-01

    The dynamics of root formation are difficult to observe directly over time without disturbing the rooting environment. A novel system for a non-destructive, non-invasive root analysis (RootViz FS, Phenotype Screening Corp.) was evaluated for its ability to analyze root formation from cuttings over a 32 day period in three poplar genotypes (DN70, P. Deltoides x...

  16. Research on non-destructive testing method of silkworm cocoons based on image processing technology

    NASA Astrophysics Data System (ADS)

    Gan, Yong; Kong, Qing-hua; Wei, Li-fu

    2008-03-01

    The major studied in this dissertation is the non-destructive testing method of silkworm cocoon's quality, based on the digital image processing and photoelectricity technology. Through the images collection and the data analysis, procession and calculation of the tested silkworm cocoons with the non-destructive testing technology, internet applications automatically reckon all items of the classification indexes. Finally we can conclude the classification result and the purchase price of the silkworm cocoons. According to the domestic classification standard of the silkworm cocoons, the author investigates various testing methods of silkworm cocoons which are used or have been explored at present, and devices a non-destructive testing scheme of the silkworm cocoons based on the digital image processing and photoelectricity technology. They are dissertated about the project design of the experiment. The precisions of all the implements are demonstrated. I establish Manifold mathematic models, compare them with each other and analyze the precision with technology of databank to get the best mathematic model to figure out the weight of the dried silkworm cocoon shells. The classification methods of all the complementary items are designed well and truly. The testing method has less error and reaches an advanced level of the present domestic non-destructive testing technology of the silkworm cocoons.

  17. Measuring low-level porosity structures by using a non-destructive terahertz inspection system

    NASA Astrophysics Data System (ADS)

    Liu, Hongwei; Ke, Lin

    2017-09-01

    It is demanded a non-contact, non-destructive and reliable system and method of porosity measurement because conventional techniques are contact and cubersome. We have developed a method by using THz inspection system, which allows measuring the porosity rapidly and non-invasively, by introducing an external perturbation. The embodiments of the external perturbation can be mechanical or pulsed laser.

  18. Non-destructive assessment of human ribs mechanical properties using quantitative ultrasound.

    PubMed

    Mitton, David; Minonzio, Jean-Gabriel; Talmant, Maryline; Ellouz, Rafaa; Rongieras, Frédéric; Laugier, Pascal; Bruyère-Garnier, Karine

    2014-04-11

    Advanced finite element models of the thorax have been developed to study, for example, the effects of car crashes. While there is a need for material properties to parameterize such models, specific properties are largely missing. Non-destructive techniques applicable in vivo would, therefore, be of interest to support further development of thorax models. The only non-destructive technique available today to derive rib bone properties would be based on quantitative computed tomography that measures bone mineral density. However, this approach is limited by the radiation dose. Bidirectional ultrasound axial transmission was developed on long bones ex vivo and used to assess in vivo health status of the radius. However, it is currently unknown if the ribs are good candidates for such a measurement. Therefore, the goal of this study is to evaluate the relationship between ex vivo ultrasonic measurements (axial transmission) and the mechanical properties of human ribs to determine if the mechanical properties of the ribs can be quantified non-destructively. The results show statistically significant relationships between the ultrasonic measurements and mechanical properties of the ribs. These results are promising with respect to a non-destructive and non-ionizing assessment of rib mechanical properties. This ex vivo study is a first step toward in vivo studies to derive subject-specific rib properties.

  19. Modeling exposure to air pollution from the WTC disaster based on reports of perceived air pollution.

    PubMed

    Lederman, Sally Ann; Becker, Mark; Sheets, Stephen; Stein, Janet; Tang, Deliang; Weiss, Lisa; Perera, Frederica P

    2008-04-01

    We examined the utility of a newly developed perceived air pollution (PAP) scale and of a modeled air pollution (MAP) scale derived from it for predicting previously observed birth outcomes of pregnant women enrolled following September 11, 2001. Women reported their home and work locations in the four weeks after September 11, 2001 and the PAP at each site on a four-point scale designed for this purpose. Locations were geocoded and their distance from the World Trade Center (WTC) site determined. PAP values were used to develop a model of air pollution for a 20-mile radius from the WTC site. MAP values were assigned to each geocoded location. We examined the relationship of PAP and MAP values to maternal characteristics and to distance of home and work sites from the WTC site. Both PAP and MAP values were highly correlated with distance from the WTC. Maternal characteristics that were associated with PAP values reported for home or work sites (race, demoralization, material hardship, first trimester on September 11) were not associated with modeled MAP values. Relationships of several birth outcomes to proximity to the WTC, which we previously reported using this data set, were also seen when MAP values were used as the measure of exposure, instead of proximity. MAP developed from reports of PAP may be useful to identify high-risk areas and predict health outcomes when there are multiple sources of pollution and a "distance from source" analysis is impossible.

  20. Occupational Exposure to Urban Air Pollution and Allergic Diseases

    PubMed Central

    Vimercati, Luigi; Gatti, Maria Franca; Baldassarre, Antonio; Nettis, Eustachio; Favia, Nicola; Palma, Marco; Martina, Gabriella Lucia Maria; Di Leo, Elisabetta; Musti, Marina

    2015-01-01

    Exposure to air pollution is associated with increased morbidity from cardiovascular diseases, lung cancer, respiratory and allergic diseases. The aim of this study was to investigate allergic diseases in 111 traffic wardens compared to a control group of 101 administrative employees. All participating subjects underwent a physical examination, in which a complete medical history was taken and a dedicated allergological questionnaire administered. Spirometry, Specific IgE dosage (RAST) and skin prick tests (SPT) were done. Diagnostic investigations such as the nasal cytology, a specific nasal provocation test and rhinomanometry were also performed. Statistical analyses were performed using STATA version 11. The percentage of subjects with a diagnosis of allergy was higher in the exposed workers than in the controls. As regards the clinical tests, the positivity was higher for the group of exposed subjects. Among the exposed workers, those who worked on foot or motorcycle had a higher positivity in clinical trials compared to the traffic wardens who used the car. Our study showed a higher percentage of allergic subjects in the group of workers exposed to outdoor pollutants than in the controls. These results suggest that allergological tests should be included in the health surveillance protocols for workers exposed to outdoor pollutants. PMID:26501303

  1. Occupational Exposure to Urban Air Pollution and Allergic Diseases.

    PubMed

    Vimercati, Luigi; Gatti, Maria Franca; Baldassarre, Antonio; Nettis, Eustachio; Favia, Nicola; Palma, Marco; Martina, Gabriella Lucia Maria; Di Leo, Elisabetta; Musti, Marina

    2015-10-16

    Exposure to air pollution is associated with increased morbidity from cardiovascular diseases, lung cancer, respiratory and allergic diseases. The aim of this study was to investigate allergic diseases in 111 traffic wardens compared to a control group of 101 administrative employees. All participating subjects underwent a physical examination, in which a complete medical history was taken and a dedicated allergological questionnaire administered. Spirometry, Specific IgE dosage (RAST) and skin prick tests (SPT) were done. Diagnostic investigations such as the nasal cytology, a specific nasal provocation test and rhinomanometry were also performed. Statistical analyses were performed using STATA version 11. The percentage of subjects with a diagnosis of allergy was higher in the exposed workers than in the controls. As regards the clinical tests, the positivity was higher for the group of exposed subjects. Among the exposed workers, those who worked on foot or motorcycle had a higher positivity in clinical trials compared to the traffic wardens who used the car. Our study showed a higher percentage of allergic subjects in the group of workers exposed to outdoor pollutants than in the controls. These results suggest that allergological tests should be included in the health surveillance protocols for workers exposed to outdoor pollutants.

  2. Novel computational identification of highly selective biomarkers of pollutant exposure.

    PubMed

    Weisman, David; Liu, Hong; Redfern, Jessica; Zhu, Liya; Colón-Carmona, Adán

    2011-06-15

    The use of in vivo biosensors to acquire environmental pollution data is an emerging and promising paradigm. One major challenge is the identification of highly specific biomarkers that selectively report exposure to a target pollutant, while remaining quiescent under a diverse set of other, often unknown, environmental conditions. This study hypothesized that a microarray data mining approach can identify highly specific biomarkers, and, that the robustness property can generalize to unforeseen environmental conditions. Starting with Arabidopsis thaliana microarray data measuring responses to a variety of treatments, the study used the top scoring pair (TSP) algorithm to identify mRNA transcripts that respond uniquely to phenanthrene, a model polycyclic aromatic hydrocarbon. Subsequent in silico analysis with a larger set of microarray data indicated that the biomarkers remained robust under new conditions. Finally, in vivo experiments were performed with unforeseen conditions that mimic phenanthrene stress, and the biomarkers were assayed using qRT-PCR. In these experiments, the biomarkers always responded positively to phenanthrene, and never responded to the unforeseen conditions, thereby supporting the hypotheses. This data mining approach requires only microarray or next-generation RNA-seq data, and, in principle, can be applied to arbitrary biomonitoring organisms and chemical exposures.

  3. Development and Evaluation of Alternative Metrics of Ambient Air Pollution Exposure for Use in Epidemiologic Studies

    EPA Science Inventory

    Population-based epidemiologic studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available outdoor concentrations from central monitoring sites. This practice may in...

  4. MANAGING EXPOSURE TO INDOOR AIR POLLUTANTS IN RESIDENTIAL AND OFFICE ENVIRONMENTS

    EPA Science Inventory

    The paper discusses the factors to be considered in managing indoor air pollutants in residential and office environments to reduce occupant exposures. Techniques for managing indoor air pollution sources include: source elimination, substitution, modification, and pretreatment a...

  5. MANAGING EXPOSURE TO INDOOR AIR POLLUTANTS IN RESIDENTIAL AND OFFICE ENVIRONMENTS

    EPA Science Inventory

    The paper discusses the factors to be considered in managing indoor air pollutants in residential and office environments to reduce occupant exposures. Techniques for managing indoor air pollution sources include: source elimination, substitution, modification, and pretreatment a...

  6. Development and Evaluation of Alternative Metrics of Ambient Air Pollution Exposure for Use in Epidemiologic Studies

    EPA Science Inventory

    Population-based epidemiologic studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available outdoor concentrations from central monitoring sites. This practice may in...

  7. Spatial resolution requirements for traffic-related air pollutant exposure evaluations

    EPA Science Inventory

    Vehicle emissions represent one of the most important air pollution sources in most urban areas, and elevated concentrations of pollutants found near major roads have been associated with many adverse health impacts. To understand these impacts, exposure estimates should reflect ...

  8. ADDRESSING HUMAN EXPOSURES TO AIR POLLUTANTS AROUND BUILDINGS IN URBAN AREAS WITH COMPUTATIONAL FLUID DYNAMICS MODELS

    EPA Science Inventory

    This paper discusses the status and application of Computational Fluid Dynamics (CFD) models to address challenges for modeling human exposures to air pollutants around urban building microenvironments. There are challenges for more detailed understanding of air pollutant sour...

  9. ADDRESSING HUMAN EXPOSURES TO AIR POLLUTANTS AROUND BUILDINGS IN URBAN AREAS WITH COMPUTATIONAL FLUID DYNAMICS MODELS

    EPA Science Inventory

    This paper discusses the status and application of Computational Fluid Dynamics (CFD) models to address challenges for modeling human exposures to air pollutants around urban building microenvironments. There are challenges for more detailed understanding of air pollutant sour...

  10. Design and use of an exposure chamber for air pollution studies on microarthropods

    SciTech Connect

    Andre, H.M.

    1982-10-01

    An exposure chamber for studying the effects of air pollution on microarthropods is described. The chamber was tested on a corticolous mite, Humerobates rostrolamellatus Grandjean (Acari: Oribatida). In the absence of pollutants, the overall mortality was about 2.5%.

  11. Spatial resolution requirements for traffic-related air pollutant exposure evaluations

    EPA Science Inventory

    Vehicle emissions represent one of the most important air pollution sources in most urban areas, and elevated concentrations of pollutants found near major roads have been associated with many adverse health impacts. To understand these impacts, exposure estimates should reflect ...

  12. Effects of travel mode on exposures to particulate air pollution.

    PubMed

    Briggs, David J; de Hoogh, Kees; Morris, Chloe; Gulliver, John

    2008-01-01

    Monitoring was carried out of particulate concentrations whilst simultaneously walking and driving 48 routes in London, UK. Monitoring was undertaken during May and June 2005. Route lengths ranged from 601 to 1351 m, and most routes were travelled in both directions. Individual journey times ranged from 1.5 to 15 min by car (average 3.7 min) and 7.3 to 30 min (average 12.8 min) whilst walking; car trips were therefore repeated up to 5 times for each single walking trip and the results averaged for the route. Car trips were made with windows closed and the ventilation system on a moderate setting. Results show that mean exposures while walking are greatly in excess of those while driving, by a factor 4.7 for the coarse particle mass (PM10-PM2.5), 2.2 for the fine particle mass (PM2.5-PM1), 1.9 for the very fine particle mass (exposures appear to occur largely because the filtration system helps to prevent ingress of particles, so that the vehicle acts as a more-or-less independent micro-environment, insulated against much of air pollution present in the street. When account is also taken of the additional travel time involved in walking, these excesses are further increased: to factors of 15.6, 7.4, 6.5 and 4.4, respectively. Individuals who change their travel mode from car to walking in response to policies aimed at encouraging a modal shift in travel behavior are thus likely to experience considerably increased journey-time personal exposures to traffic-related air pollution. More effort is consequently needed to increase separation between road vehicles and pedestrians if negative effects of these policies are to be avoided.

  13. Air Quality Modeling in Support of the Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS)

    EPA Science Inventory

    A major challenge in traffic-related air pollution exposure studies is the lack of information regarding pollutant exposure characterization. Air quality modeling can provide spatially and temporally varying exposure estimates for examining relationships between traffic-related a...

  14. Windsor, Ontario Exposure Assessment Study: Design and Methods Validation of Personal, Indoor and Outdoor Air Pollution Monitoring

    EPA Science Inventory

    The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In addition, the role of personal, indoor, and outdoor air pollution exposures...

  15. Windsor, Ontario Exposure Assessment Study: Design and Methods Validation of Personal, Indoor and Outdoor Air Pollution Monitoring

    EPA Science Inventory

    The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In addition, the role of personal, indoor, and outdoor air pollution exposures...

  16. Air Quality Modeling in Support of the Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS)

    EPA Science Inventory

    A major challenge in traffic-related air pollution exposure studies is the lack of information regarding pollutant exposure characterization. Air quality modeling can provide spatially and temporally varying exposure estimates for examining relationships between traffic-related a...

  17. Satellite-aided evaluation of population exposure to air pollution

    USGS Publications Warehouse

    Todd, William J.; George, Anthony J.; Bryant, Nevin A.

    1979-01-01

    The Clean Air Act Amendments of 1977 set schedules for states to implement regional, spatial assessments of air quality impacts. Accordingly, the U.S. Environmental Protection Agency recently published guidelines for quantifying population exposure to adverse air quality impact by using air quality and population data by census tracts. Our research complements the EPA guidelines in that it demonstrates the ability to determine population exposure to air pollution through computer processing that utilizes Landsat satellite-derived land use information. Three variables-a 1985 estimate of total suspended particulates for 2-km2 grid cells, Landsat-derived residential land cover data for 0.45-ha cells, and population totals for census tracts-were spatially registered and cross-tabulated to produce tabular and map products illustrating relative air quality exposure for residential population by 2-km2 cells. It would cost $20,000 to replicate our analysis for an area similar in size to the 4000-km2 Portland area. Once completed, the spatially fine, computer-compatible air quality and population data are amenable to the timely and efficient generation of population-at-risk tabular and map information on a continuous or periodic basis.

  18. A study of spatial resolution in pollution exposure modelling

    PubMed Central

    Stroh, Emilie; Harrie, Lars; Gustafsson, Susanna

    2007-01-01

    Background This study is part of several ongoing projects concerning epidemiological research into the effects on health of exposure to air pollutants in the region of Scania, southern Sweden. The aim is to investigate the optimal spatial resolution, with respect to temporal resolution, for a pollutant database of NOx-values which will be used mainly for epidemiological studies with durations of days, weeks or longer periods. The fact that a pollutant database has a fixed spatial resolution makes the choice critical for the future use of the database. Results The results from the study showed that the accuracy between the modelled concentrations of the reference grid with high spatial resolution (100 m), denoted the fine grid, and the coarser grids (200, 400, 800 and 1600 meters) improved with increasing spatial resolution. When the pollutant values were aggregated in time (from hours to days and weeks) the disagreement between the fine grid and the coarser grids were significantly reduced. The results also illustrate a considerable difference in optimal spatial resolution depending on the characteristic of the study area (rural or urban areas). To estimate the accuracy of the modelled values comparison were made with measured NOx values. The mean difference between the modelled and the measured value were 0.6 μg/m3 and the standard deviation 5.9 μg/m3 for the daily difference. Conclusion The choice of spatial resolution should not considerably deteriorate the accuracy of the modelled NOx values. Considering the comparison between modelled and measured values we estimate that an error due to coarse resolution greater than 1 μg/m3 is inadvisable if a time resolution of one day is used. Based on the study of different spatial resolutions we conclude that for urban areas a spatial resolution of 200–400 m is suitable; and for rural areas the spatial resolution could be coarser (about 1600 m). This implies that we should develop a pollutant database that allows

  19. Systematic review and metaanalysis of air pollution exposure and risk of diabetes.

    PubMed

    Janghorbani, Mohsen; Momeni, Fatemeh; Mansourian, Marjan

    2014-04-01

    The present systematic review and metaanalysis of published observational studies was conducted to assess the health effects of exposure to air pollution on diabetes risk. Online databases were searched through January 2013, and the reference lists of pertinent articles reporting observational studies in humans were examined. Pooled relative risks and 95 % confidence intervals were calculated with a random-effects model. Exposure to air pollution was associated with slight increase in risk of diabetes and susceptibility of people with diabetes to air pollution. These results were consistent between time-series, case-crossover and cohort studies and between studies conducted in North America and Europe. The association between exposure to air pollution and diabetes was stronger for gaseous pollutants than for particulate matter. Our metaanalysis suggests that exposure to air pollution may be a risk factor for diabetes and increase susceptibility of people with diabetes to air pollution.

  20. Development and evaluation of alternative approaches for exposure assessment of multiple air pollutants in Atlanta, Georgia

    EPA Science Inventory

    Measurements from central site (CS) monitors are often used as estimates of exposure in air pollution epidemiological studies. As these measurements are typically limited in their spatiotemporal resolution, true exposure variability within a population is often obscured, leading ...

  1. COOPERATIVE RESEARCH AND DEVELOPMENT FOR APPLICATION OF CFD TO ESTIMATING HUMAN EXPOSURES TO ENVIRONMENTAL POLLUTANTS

    EPA Science Inventory

    Under a Cooperative Research and Development Agreement (CRADA), Fluent, Inc. and the US EPA National Exposure Research Laboratory (NERL) propose to improve the ability of environmental scientists to use computer modeling for environmental exposure to air pollutants in human exp...

  2. COOPERATIVE RESEARCH AND DEVELOPMENT FOR APPLICATION OF CFD TO ESTIMATING HUMAN EXPOSURES TO ENVIRONMENTAL POLLUTANTS

    EPA Science Inventory

    Under a Cooperative Research and Development Agreement (CRADA), Fluent, Inc. and the US EPA National Exposure Research Laboratory (NERL) propose to improve the ability of environmental scientists to use computer modeling for environmental exposure to air pollutants in human exp...

  3. Development and evaluation of alternative approaches for exposure assessment of multiple air pollutants in Atlanta, Georgia

    EPA Science Inventory

    Measurements from central site (CS) monitors are often used as estimates of exposure in air pollution epidemiological studies. As these measurements are typically limited in their spatiotemporal resolution, true exposure variability within a population is often obscured, leading ...

  4. Identifying exposure disparities in air pollution epidemiology specific to adverse birth outcomes

    NASA Astrophysics Data System (ADS)

    Geer, Laura A.

    2014-10-01

    More than 147 million people in the US live in areas where pollutant levels are above regulatory limits and pose a risk to health. Most of the vast network of air pollutant monitors in the US are located in places with higher pollution levels and a higher density of pollutant sources (e.g., point sources from industrial pollution). Vulnerable populations are more likely to live closer to pollutant sources, and thus closer to pollutant monitors. These differential exposures have an impact on maternal and child health; maternal air pollutant exposures have been linked to adverse outcomes such as preterm birth and infant low birth weight. Several studies are highlighted that address methodological approaches in the study of air pollution and health disparities.

  5. Post-Irradiation Non-Destructive Analyses of the AFIP-7 Experiment

    NASA Astrophysics Data System (ADS)

    Williams, W. J.; Robinson, A. B.; Rabin, B. H.

    2017-08-01

    This article reports the results and interpretation of post-irradiation non-destructive examinations performed on four curved full-size fuel plates that comprise the AFIP-7 experiment. These fuel plates, having a U-10 wt.%Mo monolithic design, were irradiated under moderate operating conditions in the Advanced Test Reactor to assess fuel performance for geometries that are prototypic of research reactor fuel assemblies. Non-destructive examinations include visual examination, neutron radiography, profilometry, and precision gamma scanning. This article evaluates the qualitative and quantitative data taken for each plate, compares corresponding data sets, and presents the results of swelling analyses. These characterization results demonstrate that the fuel meets established irradiation performance requirements for mechanical integrity, geometric stability, and stable and predictable behavior.

  6. Photoacoustic Spectroscopy as a Non-destructive Tool for Quantification of Pesticide Residue in Apple Cuticle

    NASA Astrophysics Data System (ADS)

    Liu, Lixian; Wang, Yafei; Gao, Chunming; Huan, Huiting; Zhao, Binxing; Yan, Laijun

    2015-06-01

    Photoacoustic spectroscopy (PAS), the non-destructive method to detect residue of dimethyl-dichloro-vinyl-phosphate (DDVP) pesticide in a cuticle of apple, is described. After constructing the PA experimental setup and identifying three characteristic peaks of DDVP in the near ultraviolet region, the PA spectra of an apple cuticle contaminated with DDVP were collected. The artificial neural network method was then applied to analyze data quantitatively. The results show a correlation coefficient exceeding 0.99 and a detection limit of 0.2 ppm, which is within the national food safety standard for maximum residue limits for pesticides in food (GB 2763-2012). This fact and the non-destructive character of PAS make the approach promising for detection of pesticide residue in fruits.

  7. Non-destructive quality control of kiwi fruits by hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Serranti, S.; Bonifazi, G.; Luciani, V.

    2017-05-01

    This study aimed to evaluate the possibility to perform a fast, reliable and robust non-destructive monitoring of kiwifruits characteristics adopting an HyperSpectral Imaging (HSI) based approach. HSI was thus utilized for two different purposes: i) to test whether the postharvest ripeness of kiwifruits could be non-destructively determined and ii) for the diagnosis of pseudomonas infection in the Kiwi orchards. To reach the 1st goal (i.e. fruit ripening evaluation) a NIR Spectral Camera acting in the range between 900 and 1700 nm has been used. To reach the 2nd goal a hyperspectral camera working in the VIS-NIR range (400 nm - 1000 nm) was used. For both the approaches "only" significance and robustness of the collected data, in respect of the selected operative conditions, was investigated and the results have been evaluated in terms of different Principal Components (PC) images.

  8. Microwaving Blood as a Non-Destructive Technique for Haemoglobin Measurements on Microlitre Samples

    PubMed Central

    Basey-Fisher, Toby H.; Guerra, Nadia; Triulzi, Chiara; Gregory, Andrew; Hanham, Stephen M.; Stevens, Molly M.; Maier, Stefan A.; Klein, Norbert

    2016-01-01

    The non-destructive ex vivo determination of haemoglobin (Hgb) concentration offers the capability to conduct multiple red blood cell haematological measurements on a single sample, an advantage that current optical techniques are unable to offer. Here, a microwave method and device for the accurate and non-destructive determination of Hgb concentration in microlitre blood samples are described. Using broadband microwave spectroscopy, a relationship is established between the dielectric properties of murine blood and Hgb concentration that is utilized to create a technique for the determination of Hgb concentration. Subsequently, a microwave dielectric resonator-microfluidic system is implemented in the analysis of 52 murine samples with microlitre volumes and Hgb concentrations ranging from 0 to 17 g dL−1. Using the characterized relationship, independent and minimally invasive Hgb measurements are made on nine healthy mice as well as seven with mutations in the Adenomatous polyposis coli (APC) gene that leads to colorectal cancer and consequently anaemia. PMID:24002989

  9. Non-destructive measurement and monitoring of separation of charged particle micro-bunches

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Konoplev, I. V.; Lancaster, A. J.; Harrison, H.; Doucas, G.; Aryshev, A.; Shevelev, M.; Terunuma, N.; Urakawa, J.

    2017-07-01

    Micro-bunched particle beams are used for a wide range of research including wakefield-based particle acceleration and tunable sources of radiation. In all applications, accurate and non-destructive monitoring of the bunch-to-bunch separation is required. With the development of femtosecond lasers, the generation of micro-bunched beams directly from a photocathode becomes routine; however, non-destructive monitoring of the separation is still a challenge. We present the results of proof-of-principle experiments conducted at the Laser Undulator Compact X-ray accelerator measuring the distance between micro-bunches via the amplitude modulation analysis of a monochromatic radiation signal. Good agreement with theoretical predictions is shown; limitations and further improvements are discussed.

  10. Probability of detection model for the non-destructive inspection of steam generator tubes of PWRs

    NASA Astrophysics Data System (ADS)

    Yusa, N.

    2017-06-01

    This study proposes a probability of detection (POD) model to discuss the capability of non-destructive testing methods for the detection of stress corrosion cracks appearing in the steam generator tubes of pressurized water reactors. Three-dimensional finite element simulations were conducted to evaluate eddy current signals due to stress corrosion cracks. The simulations consider an absolute type pancake probe and model a stress corrosion crack as a region with a certain electrical conductivity inside to account for eddy currents flowing across a flaw. The probabilistic nature of a non-destructive test is simulated by varying the electrical conductivity of the modelled stress corrosion cracking. A two-dimensional POD model, which provides the POD as a function of the depth and length of a flaw, is presented together with a conventional POD model characterizing a flaw using a single parameter. The effect of the number of the samples on the PODs is also discussed.

  11. Non-destructive optical methods for the study of soft tissues

    NASA Astrophysics Data System (ADS)

    Santiago-Lona, Cynthia V.; Hernández-Montes, María. del Socorro; Mendoza Santoyo, F.; Muñoz, Silvino; Mendoza, Fernando

    2015-08-01

    In optical metrology, non-destructive methods allow studying some mechanical properties of the samples to investigate by using light, which leads to non-contact testing. This paper shows recent results of the application of non-destructive optical methods based on Digital Holographic Interferometry to the study biological tissues; particularly vocal folds and the tympanic membrane. The displacements data and its corresponding patterns found generates information on its characteristics that can be correlated with their physiological state. These methods prove to be an alternative viable and appropriate to characterize these soft tissues so important for the proper function of the human body. The result shows a potential impact on its possible uses in the field of otorhinolaryngology.

  12. Non-destructive imaging of buried electronic interfaces using a decelerated scanning electron beam

    PubMed Central

    Hirohata, Atsufumi; Yamamoto, Yasuaki; Murphy, Benedict A.; Vick, Andrew J.

    2016-01-01

    Recent progress in nanotechnology enables the production of atomically abrupt interfaces in multilayered junctions, allowing for an increase in the number of transistors in a processor. However, uniform electron transport has not yet been achieved across the entire interfacial area in junctions due to the existence of local defects, causing local heating and reduction in transport efficiency. To date, junction uniformity has been predominantly assessed by cross-sectional transmission electron microscopy, which requires slicing and milling processes that can potentially introduce additional damage and deformation. It is therefore essential to develop an alternative non-destructive method. Here we show a non-destructive technique using scanning electron microscopy to map buried junction properties. By controlling the electron-beam energy, we demonstrate the contrast imaging of local junction resistances at a controlled depth. This technique can be applied to any buried junctions, from conventional semiconductor and metal devices to organic devices. PMID:27586090

  13. Non-destructive imaging of buried electronic interfaces using a decelerated scanning electron beam

    NASA Astrophysics Data System (ADS)

    Hirohata, Atsufumi; Yamamoto, Yasuaki; Murphy, Benedict A.; Vick, Andrew J.

    2016-09-01

    Recent progress in nanotechnology enables the production of atomically abrupt interfaces in multilayered junctions, allowing for an increase in the number of transistors in a processor. However, uniform electron transport has not yet been achieved across the entire interfacial area in junctions due to the existence of local defects, causing local heating and reduction in transport efficiency. To date, junction uniformity has been predominantly assessed by cross-sectional transmission electron microscopy, which requires slicing and milling processes that can potentially introduce additional damage and deformation. It is therefore essential to develop an alternative non-destructive method. Here we show a non-destructive technique using scanning electron microscopy to map buried junction properties. By controlling the electron-beam energy, we demonstrate the contrast imaging of local junction resistances at a controlled depth. This technique can be applied to any buried junctions, from conventional semiconductor and metal devices to organic devices.

  14. Non-destructive imaging of buried electronic interfaces using a decelerated scanning electron beam.

    PubMed

    Hirohata, Atsufumi; Yamamoto, Yasuaki; Murphy, Benedict A; Vick, Andrew J

    2016-09-02

    Recent progress in nanotechnology enables the production of atomically abrupt interfaces in multilayered junctions, allowing for an increase in the number of transistors in a processor. However, uniform electron transport has not yet been achieved across the entire interfacial area in junctions due to the existence of local defects, causing local heating and reduction in transport efficiency. To date, junction uniformity has been predominantly assessed by cross-sectional transmission electron microscopy, which requires slicing and milling processes that can potentially introduce additional damage and deformation. It is therefore essential to develop an alternative non-destructive method. Here we show a non-destructive technique using scanning electron microscopy to map buried junction properties. By controlling the electron-beam energy, we demonstrate the contrast imaging of local junction resistances at a controlled depth. This technique can be applied to any buried junctions, from conventional semiconductor and metal devices to organic devices.

  15. PANDA—A novel instrument for non-destructive sample analysis

    NASA Astrophysics Data System (ADS)

    Turunen, Jani; Peräjärvi, Kari; Pöllänen, Roy; Toivonen, Harri

    2010-01-01

    An instrument known as PANDA (Particles And Non-Destructive Analysis) for non-destructive sample analysis has been designed and built at the Finnish Radiation and Nuclear Safety Authority (STUK). In PANDA the measurement techniques and instruments designed for the basic research are applied to the analysis of environmental samples. PANDA has two vacuum chambers, one for loading samples and the other for measurements. In the measurement chamber there are two individual measurement positions. Currently the first one hosts an HPGe gamma detector and a position-sensitive alpha detector. The second measurement position is intended for precise characterization of found particles. PANDA's data are recorded in event mode and events are timestamped. In the present article the technical design of PANDA is presented in detail. In addition, its performance using depleted uranium particles and an air filter is demonstrated.

  16. The application of non-destructive techniques to the testing of a wind turbine blade

    SciTech Connect

    Sutherland, H.; Beattie, A.; Hansche, B.; Musial, W.; Allread, J.; Johnson, J.; Summers, M.

    1994-06-01

    NonDestructive Testing (NDT), also called NonDestructive Evaluation (NDE), is commonly used to monitor structures before, during, and after testing. This paper reports on the use of two NDT techniques to monitor the behavior of a typical wind turbine blade during a quasi-static test-to-failure. The two NDT techniques used were acoustic emission and coherent optical. The former monitors the acoustic energy produced by the blade as it is loaded. The latter uses electron shearography to measure the differences in surface displacements between two load states. Typical results are presented to demonstrate the ability of these two techniques to locate and monitor both high damage regions and flaws in the blade structure. Furthermore, this experiment highlights the limitations in the techniques that must be addressed before one or both can be transferred, with a high probability of success, to the inspection and monitoring of turbine blades during the manufacturing process and under normal operating conditions.

  17. Destructive and Non-Destructive Analysis Techniques for Failure Detection of QFN Packages

    NASA Astrophysics Data System (ADS)

    Adhila, M. N.; Wedianti, S.; Suhaimi, W. S. W. M.; Aishah, I.

    2010-03-01

    One of the latest developments in packaging technology is the QFN (Quad Flat Non-Lead) packages, which is both a chip scale package and plastic encapsulated package with lead pad at the bottom. In this paper, different type of commercial QFN single die packages were characterized by using destructive and non-destructive techniques. Non-destructive techniques such as Scanning Acoustic Microscope (SAM) and X-Ray analysis were used to observe package cracking, delamination and other failure mode. Application of SAM include detection of delaminations between lead frame, die face, paddle, heat sink, cracks and plastic encapsulant. In comparison to other techniques, SAM is sensitive to detect beneath the surface of devices which would be inaccessible otherwise by both conventional optical and electron microscopy inspection methods. Destructive technique such as Field Emission Electron Microscopy (FESEM) was implemented to address the failures of the QFN single die packages such as die cracking, lifted ball bonds and other failure mode.

  18. A novel quadruple excitation in high-Tc SQUID-based non-destructive evaluation

    NASA Astrophysics Data System (ADS)

    Kong, X. Y.; Ren, Y. F.; Li, J. W.; Yu, H. W.; Chen, G. H.; Yang, Q. S.

    2006-02-01

    A high-Tc SQUID-based non-destructive evaluation (NDE) system has been set up in our laboratory. The SQUID was made on a 24° bicystal SrTiO3 substrate. A novel quadruple excitation coil was proposed for the first time and applied in the artificial holes in the aluminium multilayer structure in a noisy unshielded environment. The experimental data shows that it has good balance and is very effective at detecting small hole defects.

  19. Non-Destructive Methods of Characterising the Strength of Adhesive-Bonded Joints.

    DTIC Science & Technology

    1985-10-01

    R D-RI68 191 NON-DESTRUCTIVE METHODS OF CHRACTERISING THE STRENGTH ±i𔃻 I OF ADHESIVE-BONDED..(U) ROYAL AIRCRAFT ESTABLISHMENT I FRNBOROUGH ( ENGLAND ... UK to monitor degrada- tion by means of ultrasound have used a conventional pulse-echo approach in which the .’#" direction of the ultrasonic wave is...UNCLASSIFIED 5. DRIC Code for Originator 6. Originator (Corporate Author) Name and Location 7673000W Royal Aircraft Establishment, Farnborough, Hants, UK 5a

  20. Conceptual design of non-destructive, time profile monitor for femtosecond-long electron bunches

    NASA Astrophysics Data System (ADS)

    Konoplev, I. V.; Harrison, H.; Lancaster, A. J.; Taheri, F. Bakkali; Doucas, G.; Aryshev, A.; Lekomtsev, K.; Shevelev, M.; Terunuma, N.; Urakawa, J.

    2017-03-01

    The main objective of the project is to build a high resolution time-profile monitor for femtosecond electron beams, based on the spectral analysis of coherent Smith-Purcell radiation (cSPr). The monitor will be capable of determining the electron bunch time profile non-destructively and on a shot-by-shot basis. The results of recent experimental and theoretical studies are presented, and the conceptual design of the monitor is discussed.

  1. Coded excitation for infrared non-destructive testing of carbon fiber reinforced plastics.

    PubMed

    Mulaveesala, Ravibabu; Venkata Ghali, Subbarao

    2011-05-01

    This paper proposes a Barker coded excitation for defect detection using infrared non-destructive testing. Capability of the proposed excitation scheme is highlighted with recently introduced correlation based post processing approach and compared with the existing phase based analysis by taking the signal to noise ratio into consideration. Applicability of the proposed scheme has been experimentally validated on a carbon fiber reinforced plastic specimen containing flat bottom holes located at different depths.

  2. Application of Non-destructive Methods of Stress-strain State at Hazardous Production Facilities

    NASA Astrophysics Data System (ADS)

    Shram, V.; Kravtsova, Ye; Selsky, A.; Bezborodov, Yu; Lysyannikova, N.; Lysyannikov, A.

    2016-06-01

    The paper deals with the sources of accidents in distillation columns, on the basis of which the most dangerous defects are detected. The analysis of the currently existing methods of non-destructive testing of the stress-strain state is performed. It is proposed to apply strain and acoustic emission techniques to continuously monitor dangerous objects, which helps prevent the possibility of accidents, as well as reduce the work.

  3. Development of the Portable Synchrotron MIRRORCLE-CV for High Precision Non-Destructive Testing

    SciTech Connect

    Hasegawa, Daisuke; Toyosugi, Norio; Noh, Young Deok; Yamada, Takanori; Morita, Masaki; Mantey, Edward; Masaoka, Sei; Yamada, Hironari

    2007-01-19

    We started the development of the portable synchrotron MIRRORCLE-CV series, which provides a high quality x-ray beam for high precision non-destructive testing (NDT). Computer simulations for the magnetic field design and electron dynamics reveal that the outer diameter of the synchrotron magnet can be as small as 30 cm. This synchrotron size approaches that of a conventional x-ray tube.

  4. MIRRORCLE-CV The Portable Synchrotron For Precise Non-Destructive Testing And Medical Diagnosis

    SciTech Connect

    Hasegawa, Daisuke; Yamada, Hironari

    2007-03-30

    We are developing the portable synchrotron MIRRORCLE-CV series, which provides a high quality x-ray beam for high precision non-destructive testing (NDT). Computer simulations for the magnetic field design and electron dynamics reveal that the outer diameter of the synchrotron magnet can be as small as 30 cm. This synchrotron size approaches that of a conventional x-ray tube.

  5. Metal Pollutants and Cardiovascular Disease: Mechanisms and Consequences of Exposure

    PubMed Central

    Solenkova, Natalia V.; Newman, Jonathan D.; Berger, Jeffrey S.; Thurston, George; Hochman, Judith S.; Lamas, Gervasio A.

    2014-01-01

    Introduction There is epidemiological evidence that metal contaminants may play a role in the development of atherosclerosis and its complications. Moreover, a recent clinical trial of a metal chelator had a surprisingly positive result in reducing cardiovascular events in a secondary prevention population, strengthening the link between metal exposure and cardiovascular disease (CVD). This is, therefore, an opportune moment to review evidence that exposure to metal pollutants, such as arsenic, lead, cadmium, and mercury, are significant risk factors for CVD. Methods We reviewed the English-speaking medical literature to assess and present the epidemiological evidence that 4 metals having no role in the human body (xenobiotic), mercury, lead, cadmium, and arsenic, have epidemiologic and mechanistic links to atherosclerosis and CVD. Moreover, we briefly review how the results of the Trial to Assess Chelation Therapy strengthen the link between atherosclerosis and xenobiotic metal contamination in humans. Conclusions There is strong evidence that xenobiotic metal contamination is linked to atherosclerotic disease and is a modifiable risk factor. PMID:25458643

  6. Non-destructive Phenotyping to Identify Brachiaria Hybrids Tolerant to Waterlogging Stress under Field Conditions

    PubMed Central

    Jiménez, Juan de la Cruz; Cardoso, Juan A.; Leiva, Luisa F.; Gil, Juanita; Forero, Manuel G.; Worthington, Margaret L.; Miles, John W.; Rao, Idupulapati M.

    2017-01-01

    Brachiaria grasses are sown in tropical regions around the world, especially in the Neotropics, to improve livestock production. Waterlogging is a major constraint to the productivity and persistence of Brachiaria grasses during the rainy season. While some Brachiaria cultivars are moderately tolerant to seasonal waterlogging, none of the commercial cultivars combines superior yield potential and nutritional quality with a high level of waterlogging tolerance. The Brachiaria breeding program at the International Center for Tropical Agriculture, has been using recurrent selection for the past two decades to combine forage yield with resistance to biotic and abiotic stress factors. The main objective of this study was to test the suitability of normalized difference vegetation index (NDVI) and image-based phenotyping as non-destructive approaches to identify Brachiaria hybrids tolerant to waterlogging stress under field conditions. Nineteen promising hybrid selections from the breeding program and three commercial checks were evaluated for their tolerance to waterlogging under field conditions. The waterlogging treatment was imposed by applying and maintaining water to 3 cm above soil surface. Plant performance was determined non-destructively using proximal sensing and image-based phenotyping and also destructively via harvesting for comparison. Image analysis of projected green and dead areas, NDVI and shoot biomass were positively correlated (r ≥ 0.8). Our results indicate that image analysis and NDVI can serve as non-destructive screening approaches for the identification of Brachiaria hybrids tolerant to waterlogging stress. PMID:28243249

  7. Giant Magnetoresistance Sensors: A Review on Structures and Non-Destructive Eddy Current Testing Applications

    PubMed Central

    Rifai, Damhuji; Abdalla, Ahmed N.; Ali, Kharudin; Razali, Ramdan

    2016-01-01

    Non-destructive eddy current testing (ECT) is widely used to examine structural defects in ferromagnetic pipe in the oil and gas industry. Implementation of giant magnetoresistance (GMR) sensors as magnetic field sensors to detect the changes of magnetic field continuity have increased the sensitivity of eddy current techniques in detecting the material defect profile. However, not many researchers have described in detail the structure and issues of GMR sensors and their application in eddy current techniques for nondestructive testing. This paper will describe the implementation of GMR sensors in non-destructive testing eddy current testing. The first part of this paper will describe the structure and principles of GMR sensors. The second part outlines the principles and types of eddy current testing probe that have been studied and developed by previous researchers. The influence of various parameters on the GMR measurement and a factor affecting in eddy current testing will be described in detail in the third part of this paper. Finally, this paper will discuss the limitations of coil probe and compensation techniques that researchers have applied in eddy current testing probes. A comprehensive review of previous studies on the application of GMR sensors in non-destructive eddy current testing also be given at the end of this paper. PMID:26927123

  8. Feasibility Study of Non-Destructive Techniques to Measure Corrosion in SAVY Containers

    SciTech Connect

    Davenport, Matthew Nicholas

    2016-07-15

    Stainless Steel SAVY containers are used to transport and store nuclear material. They are prone to interior corrosion in the presence of certain chemicals and a low-oxygen environment. SAVY containers also have relatively thin walls to reduce their weight, making their structural integrity more vulnerable to the effects of corrosion. A nondestructive evaluation system that finds and monitors corrosion within containers in use would improve safety conditions and preclude hazards. Non-destructive testing can determine whether oxidation or corrosion is occurring inside the SAVY containers, and there are a variety of non-destructive testing methods that may be viable. The feasibility study described will objectively decide which method best fits the requirements of the facility and the problem. To improve efficiency, the containers cannot be opened during the non-destructive examination. The chosen technique should also be user-friendly and relatively quick to apply. It must also meet facility requirements regarding wireless technology and maintenance. A feasibility study is an objective search for a new technology or product to solve a particular problem. First, the design, technical, and facility feasibility requirements are chosen and ranked in order of importance. Then each technology considered is given a score based upon a standard ranking system. The technology with the highest total score is deemed the best fit for a certain application.

  9. Non-destructive single-pass low-noise detection of ions in a beamline

    SciTech Connect

    Schmidt, Stefan; Murböck, Tobias; Birkl, Gerhard; Andelkovic, Zoran; Vogel, Manuel; Nörtershäuser, Wilfried; Stahl, Stefan

    2015-11-15

    We have conceived, built, and operated a device for the non-destructive single-pass detection of charged particles in a beamline. The detector is based on the non-resonant pick-up and subsequent low-noise amplification of the image charges induced in a cylindrical electrode surrounding the particles’ beam path. The first stage of the amplification electronics is designed to be operated from room temperature down to liquid helium temperature. The device represents a non-destructive charge counter as well as a sensitive timing circuit. We present the concept and design details of the device. We have characterized its performance and show measurements with low-energy highly charged ions (such as Ar{sup 13+}) passing through one of the electrodes of a cylindrical Penning trap. This work demonstrates a novel approach of non-destructive, low noise detection of charged particles which is, depending on the bunch structure, suitable, e.g., for ion traps, low-energy beamlines or accelerator transfer sections.

  10. Non-destructive techniques for determining the material characteristics of Cr-Mo-V rotor steel

    SciTech Connect

    Goto, Toru; Kadoya, Yoshikuni; Konishi, Takashi; Kamimura, Takeo; Suyama, Shouji; Haruki, Nirou; Ikuno, Takeshi; Yoshimura, Kouji

    1994-12-31

    Long-term service causes material deterioration, such as the accumulation of creep and fatigue damage, as well as softening and embrittlement, in the high-temperature components of fossil fuel power plants. Therefore, in order to extend plant life at minimum cost without any accidental outages, it is important to observe the material state, especially of rotors and conduct necessary repairs or replace them at the most appropriate time. Therefore, there is a need for non-destructive techniques to evaluate the material characteristics of Cr-Mo-V rotors under service. In this paper, a comparative report of non-destructive techniques using artificially aged and crept Cr-Mo-V steel specimens is given. The techniques tested include replication, hardness measurement, electro-magnetic and ultrasonic techniques, and conventional metallurgical techniques, which have been here to fore usable only in the laboratory, but due to expected advances in the non-destructive sampling of material from service rotors these techniques are now usable in the field. As a result of the studies, the features of each technique are well recognized and the suggestions for the further development of NDE methods for the evaluation of creep damage in Cr-Mo-V rotors are presented.

  11. A new non-destructive readout by using photo-recovered surface potential contrast

    NASA Astrophysics Data System (ADS)

    Wang, Le; Jin, Kui-Juan; Gu, Jun-Xing; Ma, Chao; He, Xu; Zhang, Jiandi; Wang, Can; Feng, Yu; Wan, Qian; Shi, Jin-An; Gu, Lin; He, Meng; Lu, Hui-Bin; Yang, Guo-Zhen

    2014-11-01

    Ferroelectric random access memory is still challenging in the feature of combination of room temperature stability, non-destructive readout and high intensity storage. As a non-contact and non-destructive information readout method, surface potential has never been paid enough attention because of the unavoidable decay of the surface potential contrast between oppositely polarized domains. That is mainly due to the recombination of the surface movable charges around the domain walls. Here, by introducing a laser beam into the combination of piezoresponse force microscopy and Kelvin probe force microscopy, we demonstrate that the surface potential contrast of BiFeO3 films can be recovered under light illumination. The recovering mechanism is understood based on the redistribution of the photo-induced charges driven by the internal electric field. Furthermore, we have created a 12-cell memory pattern based on BiFeO3 films to show the feasibility of such photo-assisted non-volatile and non-destructive readout of the ferroelectric memory.

  12. Giant Magnetoresistance Sensors: A Review on Structures and Non-Destructive Eddy Current Testing Applications.

    PubMed

    Rifai, Damhuji; Abdalla, Ahmed N; Ali, Kharudin; Razali, Ramdan

    2016-02-26

    Non-destructive eddy current testing (ECT) is widely used to examine structural defects in ferromagnetic pipe in the oil and gas industry. Implementation of giant magnetoresistance (GMR) sensors as magnetic field sensors to detect the changes of magnetic field continuity have increased the sensitivity of eddy current techniques in detecting the material defect profile. However, not many researchers have described in detail the structure and issues of GMR sensors and their application in eddy current techniques for nondestructive testing. This paper will describe the implementation of GMR sensors in non-destructive testing eddy current testing. The first part of this paper will describe the structure and principles of GMR sensors. The second part outlines the principles and types of eddy current testing probe that have been studied and developed by previous researchers. The influence of various parameters on the GMR measurement and a factor affecting in eddy current testing will be described in detail in the third part of this paper. Finally, this paper will discuss the limitations of coil probe and compensation techniques that researchers have applied in eddy current testing probes. A comprehensive review of previous studies on the application of GMR sensors in non-destructive eddy current testing also be given at the end of this paper.

  13. Non-destructively reading out information embedded inside real objects by using far-infrared light

    NASA Astrophysics Data System (ADS)

    Okada, Ayumi; Silapasuphakornwong, Piyarat; Suzuki, Masahiro; Torii, Hideyuki; Takashima, Youichi; Uehira, Kazutake

    2015-09-01

    This paper presents a technique that can non-destructively read out information embedded inside real objects by using far-infrared-light. We propose a technique that can protect the copyrights of digital content for homemade products using digital fabrication technologies such as those used in 3D printers. It embeds information on copyrights inside real objects produced by 3D printers by forming fine structures inside the objects as a watermark that cannot be observed from the outside. Fine structures are formed near the surface inside real objects when they are being fabricated. Information embedded inside real objects needs to be read out non-destructively. We used a technique that could non-destructively read out information from inside real objects by using far-infrared light. We conducted experiments where we structured fine cavities inside objects. The disposition of the fine domain contained valuable information. We used the flat and curved surfaces of the objects to identify them. The results obtained from the experiments demonstrated that the disposition patterns of the fine structures appeared on the surface of objects as a temperature profile when far-infrared light was irradiated on their surface. Embedded information could be read out successfully by analyzing the temperature profile images of the surface of the objects that were captured with thermography and these results demonstrated the feasibility of the technique we propose.

  14. Non-destructive analysis of extracellular matrix development in cardiovascular tissue-engineered constructs.

    PubMed

    Tuemen, M; Nguyen, D V A; Raffius, J; Flanagan, T C; Dietrich, M; Frese, J; Schmitz-Rode, T; Jockenhoevel, S

    2013-05-01

    In the field of tissue engineering, there is an increasing demand for non-destructive methods to quantify the synthesis of extracellular matrix (ECM) components such as collagens, elastin or sulphated glycosaminoglycans (sGAGs) in vitro as a quality control before clinical use. In this study, procollagen I carboxyterminal peptide (PICP), procollagen III aminoterminal peptide (PIIINP), tropoelastin and sGAGs are investigated for their potential use as non-destructive markers in culture medium of statically cultivated cell-seeded fibrin gels. Measurement of PICP as marker for type I collagen synthesis, and PIIINP as marker of type III collagen turnover, correlated well with the hydroxyproline content of the fibrin gels, with a Pearson correlation coefficient of 0.98 and 0.97, respectively. The measurement of tropoelastin as marker of elastin synthesis correlated with the amount of elastin retained in fibrin gels with a Pearson correlation coefficient of 0.99. sGAGs were retained in fibrin gels, but were not detectable in culture medium at any time of measurement. In conclusion, this study demonstrates the potential of PICP and tropoelastin as non-destructive culture medium markers for collagen and elastin synthesis. To our knowledge, this is the first study in cardiovascular tissue engineering investigating the whole of here proposed biomarkers of ECM synthesis to monitor the maturation process of developing tissue non-invasively, but for comprehensive assessment of ECM development, these biomarkers need to be investigated in further studies, employing dynamic cultivation conditions and more complex tissue constructs.

  15. Non-destructive single-pass low-noise detection of ions in a beamline.

    PubMed

    Schmidt, Stefan; Murböck, Tobias; Andelkovic, Zoran; Birkl, Gerhard; Nörtershäuser, Wilfried; Stahl, Stefan; Vogel, Manuel

    2015-11-01

    We have conceived, built, and operated a device for the non-destructive single-pass detection of charged particles in a beamline. The detector is based on the non-resonant pick-up and subsequent low-noise amplification of the image charges induced in a cylindrical electrode surrounding the particles' beam path. The first stage of the amplification electronics is designed to be operated from room temperature down to liquid helium temperature. The device represents a non-destructive charge counter as well as a sensitive timing circuit. We present the concept and design details of the device. We have characterized its performance and show measurements with low-energy highly charged ions (such as Ar(13+)) passing through one of the electrodes of a cylindrical Penning trap. This work demonstrates a novel approach of non-destructive, low noise detection of charged particles which is, depending on the bunch structure, suitable, e.g., for ion traps, low-energy beamlines or accelerator transfer sections.

  16. [Study on Non-Destructive Testing of Guqin Interior Structure Based on Computed Tomography].

    PubMed

    Zhao, De-da; Liu, Xing-e; Yang, Shu-min; Yu, Shenz; Tian, Gen-lin; Ma, Jian-feng; Wang, Qing-ping

    2015-12-01

    The wood property and production process affect quality of Guqin. At the same time, Guqin shape with cavity layout relations to the improvement of Guqin technology and inheritance, so it's very important to get the internal cavity characteristics and parameters on the condition of non-destructive the structure of Guqin. The image of interior structure in Guqin was investigated by overall scanning based on non-destructive testing technology of computed tomography, which texture of faceplate, connection method between faceplate and soleplate and interior defects were studied. The three-dimensional reconstruction of Guqin cavity was achieved through Mimics software of surface rendering method and put the two-dimensional CT tomography images convert into three-dimensional, which more complete show interior structural form in Guqin, and finally the parameter of cavity dimensions was obtained. Experimental research shows that there is significant difference in Guqin interior structure between Zhong-ni and Luo-xia type, in which the fluctuation of the interior surfacein Zhong-ni type's is larger than that in Luo-xia type; the interior volume of Zhong-ni typeis less than that of Luo-xia type, especially in Guqin neck. The accurate internal information of Guqin obtained through the computed tomography (CT) technology will provide technical support for the Guqin manufacture craft and the quality examination, as well as provide the reference in the aspect of non-destructive testing for other traditional precious internal structure research.

  17. A new non-destructive readout by using photo-recovered surface potential contrast.

    PubMed

    Wang, Le; Jin, Kui-juan; Gu, Jun-xing; Ma, Chao; He, Xu; Zhang, Jiandi; Wang, Can; Feng, Yu; Wan, Qian; Shi, Jin-an; Gu, Lin; He, Meng; Lu, Hui-bin; Yang, Guo-zhen

    2014-11-10

    Ferroelectric random access memory is still challenging in the feature of combination of room temperature stability, non-destructive readout and high intensity storage. As a non-contact and non-destructive information readout method, surface potential has never been paid enough attention because of the unavoidable decay of the surface potential contrast between oppositely polarized domains. That is mainly due to the recombination of the surface movable charges around the domain walls. Here, by introducing a laser beam into the combination of piezoresponse force microscopy and Kelvin probe force microscopy, we demonstrate that the surface potential contrast of BiFeO3 films can be recovered under light illumination. The recovering mechanism is understood based on the redistribution of the photo-induced charges driven by the internal electric field. Furthermore, we have created a 12-cell memory pattern based on BiFeO3 films to show the feasibility of such photo-assisted non-volatile and non-destructive readout of the ferroelectric memory.

  18. Non-destructive Phenotyping to Identify Brachiaria Hybrids Tolerant to Waterlogging Stress under Field Conditions.

    PubMed

    Jiménez, Juan de la Cruz; Cardoso, Juan A; Leiva, Luisa F; Gil, Juanita; Forero, Manuel G; Worthington, Margaret L; Miles, John W; Rao, Idupulapati M

    2017-01-01

    Brachiaria grasses are sown in tropical regions around the world, especially in the Neotropics, to improve livestock production. Waterlogging is a major constraint to the productivity and persistence of Brachiaria grasses during the rainy season. While some Brachiaria cultivars are moderately tolerant to seasonal waterlogging, none of the commercial cultivars combines superior yield potential and nutritional quality with a high level of waterlogging tolerance. The Brachiaria breeding program at the International Center for Tropical Agriculture, has been using recurrent selection for the past two decades to combine forage yield with resistance to biotic and abiotic stress factors. The main objective of this study was to test the suitability of normalized difference vegetation index (NDVI) and image-based phenotyping as non-destructive approaches to identify Brachiaria hybrids tolerant to waterlogging stress under field conditions. Nineteen promising hybrid selections from the breeding program and three commercial checks were evaluated for their tolerance to waterlogging under field conditions. The waterlogging treatment was imposed by applying and maintaining water to 3 cm above soil surface. Plant performance was determined non-destructively using proximal sensing and image-based phenotyping and also destructively via harvesting for comparison. Image analysis of projected green and dead areas, NDVI and shoot biomass were positively correlated (r ≥ 0.8). Our results indicate that image analysis and NDVI can serve as non-destructive screening approaches for the identification of Brachiaria hybrids tolerant to waterlogging stress.

  19. A new non-destructive readout by using photo-recovered surface potential contrast

    PubMed Central

    Wang, Le; Jin, Kui-juan; Gu, Jun-xing; Ma, Chao; He, Xu; Zhang, Jiandi; Wang, Can; Feng, Yu; Wan, Qian; Shi, Jin-an; Gu, Lin; He, Meng; Lu, Hui-bin; Yang, Guo-zhen

    2014-01-01

    Ferroelectric random access memory is still challenging in the feature of combination of room temperature stability, non-destructive readout and high intensity storage. As a non-contact and non-destructive information readout method, surface potential has never been paid enough attention because of the unavoidable decay of the surface potential contrast between oppositely polarized domains. That is mainly due to the recombination of the surface movable charges around the domain walls. Here, by introducing a laser beam into the combination of piezoresponse force microscopy and Kelvin probe force microscopy, we demonstrate that the surface potential contrast of BiFeO3 films can be recovered under light illumination. The recovering mechanism is understood based on the redistribution of the photo-induced charges driven by the internal electric field. Furthermore, we have created a 12-cell memory pattern based on BiFeO3 films to show the feasibility of such photo-assisted non-volatile and non-destructive readout of the ferroelectric memory. PMID:25381929

  20. Non-destructive mapping of grain orientations in 3D by laboratory X-ray microscopy

    PubMed Central

    McDonald, S. A.; Reischig, P.; Holzner, C.; Lauridsen, E. M.; Withers, P. J.; Merkle, A. P.; Feser, M.

    2015-01-01

    The ability to characterise crystallographic microstructure, non-destructively and in three-dimensions, is a powerful tool for understanding many aspects related to damage and deformation mechanisms in polycrystalline materials. To this end, the technique of X-ray diffraction contrast tomography (DCT) using monochromatic synchrotron and polychromatic laboratory X-ray sources has been shown to be capable of mapping crystal grains and their orientations non-destructively in 3D. Here we describe a novel laboratory-based X-ray DCT modality (LabDCT), enabling the wider accessibility of the DCT technique for routine use and in-depth studies of, for example, temporal changes in crystallographic grain structure non-destructively over time through ‘4D’ in situ time-lapse studies. The capability of the technique is demonstrated by studying a titanium alloy (Ti-β21S) sample. In the current implementation the smallest grains that can be reliably detected are around 40 μm. The individual grain locations and orientations are reconstructed using the LabDCT method and the results are validated against independent measurements from phase contrast tomography and electron backscatter diffraction respectively. Application of the technique promises to provide important insights related to the roles of recrystallization and grain growth on materials properties as well as supporting 3D polycrystalline modelling of materials performance. PMID:26494523

  1. Study on infrared differential thermal non-destructive testing technology of the permeability of hot mix asphalt pavements

    NASA Astrophysics Data System (ADS)

    Wang, Duanyi; Shi, Jicun

    2017-06-01

    In order to non-destructive test (NDT) the permeability coefficient of hot mix asphalt (HMA) pavements fast, A methodology for assessing the permeability coefficient was proposed by infrared differential thermal testing of pavement after rain. The relationship between permeability coefficient and air voids of HMA specimen deter-mined. Finite element method (FEM) models were built to calculate the surface temperature difference with different exposure time after precipitation. Simulated solar radiation source and fully saturated plate specimens were set in laboratory, tests verify that the different exposure time the specimen surface temperature difference. Infrared differential thermal detection permeable pavement hardware and corresponding software developed. Based on many test results, the evaluation index and criteria of permeability coefficient of HMA pavements tested by infrared differential thermal were developed. The results showed that: There is correlation between air voids and permeability coefficient of HMA specimen. Permeability coefficient of HMA pavements can be determined by different surface temperature at different exposure time. 9:00 am - 14:00 pm is the best time to detect permeability coefficient by infrared differential thermal NDT. Permeable asphalt pavement permeability can be achieved by infrared detector quickly and continuously, a lane testing; Per the permeable assessment criteria, in-place pavements permeability coefficients can be accurately evaluated.

  2. A non-destructive BFCOD assay for in vivo measurement of cytochrome P450 3A (CYP3A) enzyme activity in fish embryos and larvae.

    PubMed

    Oziolor, Elias M; Carey, Alexis N; Matson, Cole W

    2017-08-01

    There is increasing interest in quantifying the exposure and effects of anthropogenic contaminants in fish. Determination of exposures in wild fish is routinely performed, but methods to investigate potential effects are less established. One of the most relevant approaches would be the use of in vivo assays, but existing assays are often limited to in vitro determination of enzyme activity. Many pharmaceuticals and some persistent pollutants activate, and are metabolized by cytochrome P4503A (CYP3A), which make it a relevant and desirable target for biomarker research. We altered the established 7-benzyloxy-4-trifluoromethylcoumarin-O-debenzylation (BFCOD) in vitro protocol for CYP3A activity determination, developing a rapid and inexpensive method to measure in vivo (and in ovo) CYP3A activity in two fish systems: Gulf killifish (Fundulus grandis) and zebrafish (Danio rerio) early life stages. Even with very low concentrations of 7-benzyloxy-4-trifluoromethyl coumarin (BFC, 0.06 µM or 20 µg/L), we were able to detect significant induction in CYP3A activity in embryos of F. grandis, as well as in larvae of D. rerio in response to benzo[a]pyrene (BaP) and fluoranthene (FL) exposures. Because of concerns regarding the possible contribution of CYP1A to BFCOD activity from previous research, we have used a CYP1A post-translational inhibitor (FL) in order to calculate the contribution of CYP1A to the BFCOD assay. We also dosed with benzo[k]fluoranthene (BkF) and showed significant induction of CYP1A activity, with no concurrent increase in CYP3A activity. In this paper, we have taken an established in vitro CYP3A activity assay, and utilized the reaction in a novel way to allow for the non-destructive determination of CYP3A. In summary, we describe a sensitive, cheap, fast and easy modified BFCOD assay for in ovo and in vivo determination of CYP3A activity for use in moderate throughput early-life-stage fish experiments.

  3. Air pollution dispersion models for human exposure predictions in London.

    PubMed

    Beevers, Sean D; Kitwiroon, Nutthida; Williams, Martin L; Kelly, Frank J; Ross Anderson, H; Carslaw, David C

    2013-01-01

    The London household survey has shown that people travel and are exposed to air pollutants differently. This argues for human exposure to be based upon space-time-activity data and spatio-temporal air quality predictions. For the latter, we have demonstrated the role that dispersion models can play by using two complimentary models, KCLurban, which gives source apportionment information, and Community Multi-scale Air Quality Model (CMAQ)-urban, which predicts hourly air quality. The KCLurban model is in close agreement with observations of NO(X), NO(2) and particulate matter (PM)(10/2.5), having a small normalised mean bias (-6% to 4%) and a large Index of Agreement (0.71-0.88). The temporal trends of NO(X) from the CMAQ-urban model are also in reasonable agreement with observations. Spatially, NO(2) predictions show that within 10's of metres of major roads, concentrations can range from approximately 10-20 p.p.b. up to 70 p.p.b. and that for PM(10/2.5) central London roadside concentrations are approximately double the suburban background concentrations. Exposure to different PM sources is important and we predict that brake wear-related PM(10) concentrations are approximately eight times greater near major roads than at suburban background locations. Temporally, we have shown that average NO(X) concentrations close to roads can range by a factor of approximately six between the early morning minimum and morning rush hour maximum periods. These results present strong arguments for the hybrid exposure model under development at King's and, in future, for in-building models and a model for the London Underground.

  4. Multi-pollutant exposure profiles associated with term low birth weight in Los Angeles County.

    PubMed

    Coker, Eric; Liverani, Silvia; Ghosh, Jo Kay; Jerrett, Michael; Beckerman, Bernardo; Li, Arthur; Ritz, Beate; Molitor, John

    2016-05-01

    Research indicates that multiple outdoor air pollutants and adverse neighborhood conditions are spatially correlated. Yet health risks associated with concurrent exposure to air pollution mixtures and clustered neighborhood factors remain underexplored. Statistical models to assess the health effects from pollutant mixtures remain limited, due to problems of collinearity between pollutants and area-level covariates, and increases in covariate dimensionality. Here we identify pollutant exposure profiles and neighborhood contextual profiles within Los Angeles (LA) County. We then relate these profiles with term low birth weight (TLBW). We used land use regression to estimate NO2, NO, and PM2.5 concentrations averaged over census block groups to generate pollutant exposure profile clusters and census block group-level contextual profile clusters, using a Bayesian profile regression method. Pollutant profile cluster risk estimation was implemented using a multilevel hierarchical model, adjusting for individual-level covariates, contextual profile cluster random effects, and modeling of spatially structured and unstructured residual error. Our analysis found 13 clusters of pollutant exposure profiles. Correlations between study pollutants varied widely across the 13 pollutant clusters. Pollutant clusters with elevated NO2, NO, and PM2.5 concentrations exhibited increased log odds of TLBW, and those with low PM2.5, NO2, and NO concentrations showed lower log odds of TLBW. The spatial patterning of pollutant cluster effects on TLBW, combined with between-pollutant correlations within pollutant clusters, imply that traffic-related primary pollutants influence pollutant cluster TLBW risks. Furthermore, contextual clusters with the greatest log odds of TLBW had more adverse neighborhood socioeconomic, demographic, and housing conditions. Our data indicate that, while the spatial patterning of high-risk multiple pollutant clusters largely overlaps with adverse contextual

  5. Synergistic effects of exposure to concentrated ambient fine pollution particles and nitrogen dioxide in humans

    EPA Science Inventory

    Exposure to single pollutants such as ambient particulate matter (PM) is associated with adverse health effects. It is unclear, however, if simultaneous exposure to multiple air pollutants (e.g. PM and ozone or nitrogen dioxide), a more real world scenario, results in non-additiv...

  6. Synergistic effects of exposure to concentrated ambient fine pollution particles and nitrogen dioxide in humans

    EPA Science Inventory

    Exposure to single pollutants such as ambient particulate matter (PM) is associated with adverse health effects. It is unclear, however, if simultaneous exposure to multiple air pollutants (e.g. PM and ozone or nitrogen dioxide), a more real world scenario, results in non-additiv...

  7. Exposure prediction approaches used in air pollution epidemiology studies: Key findings and future recommendations

    PubMed Central

    Baxter, Lisa K.; Dionisio, Kathie L.; Burke, Janet; Sarnat, Stefanie Ebelt; Sarnat, Jeremy A.; Hodas, Natasha; Rich, David Q.; Turpin, Barbara J.; Jones, Rena R.; Mannshardt, Elizabeth; Kumar, Naresh; Beevers, Sean D.; Özkaynak, Halûk

    2014-01-01

    Many epidemiologic studies of the health effects of exposure to ambient air pollution use measurements from central-site monitors as their exposure estimate. However, measurements from central-site monitors may lack the spatial and temporal resolution required to capture exposure variability in a study population, thus resulting in exposure error and biased estimates. Articles in this dedicated issue examine various approaches to predict or assign exposures to ambient pollutants. These methods include: combining existing central-site pollution measurements with local- and/or regional-scale air quality models to create new or “hybrid” models for pollutant exposure estimates, and using exposure models to account for factors such as infiltration of pollutants indoors and human activity patterns. Key findings from these articles are summarized to provide lessons learned and recommendations for additional research on improving exposure estimation approaches for future epidemiological studies. In summary, when compared to use of central-site monitoring data, the enhanced spatial resolution of air quality or exposure models can have an impact on resultant health effect estimates, especially for pollutants derived from local sources such as traffic (e.g. EC, CO, and NOx). In addition, the optimal exposure estimation approach also depends upon the epidemiological study design. We recommend that future research develop pollutant-specific infiltration data (including for PM species), and improve existing data on human time-activity patterns, and exposure to local source (e.g. traffic), in order to enhance human exposure modeling estimates. We also recommend comparing how various approaches to exposure estimation characterize relationships between multiple pollutants in time and space, and investigating the impact of improved exposure estimates in chronic health studies. PMID:24084756

  8. Towards Personal Exposures: How Technology Is Changing Air Pollution and Health Research.

    PubMed

    Larkin, A; Hystad, P

    2017-10-05

    We present a review of emerging technologies and how these can transform personal air pollution exposure assessment and subsequent health research. Estimating personal air pollution exposures is currently split broadly into methods for modeling exposures for large populations versus measuring exposures for small populations. Air pollution sensors, smartphones, and air pollution models capitalizing on big/new data sources offer tremendous opportunity for unifying these approaches and improving long-term personal exposure prediction at scales needed for population-based research. A multi-disciplinary approach is needed to combine these technologies to not only estimate personal exposures for epidemiological research but also determine drivers of these exposures and new prevention opportunities. While available technologies can revolutionize air pollution exposure research, ethical, privacy, logistical, and data science challenges must be met before widespread implementations occur. Available technologies and related advances in data science can improve long-term personal air pollution exposure estimates at scales needed for population-based research. This will advance our ability to evaluate the impacts of air pollution on human health and develop effective prevention strategies.

  9. Early life exposure to air pollution induces adult cardiac dysfunction

    PubMed Central

    Gorr, Matthew W.; Velten, Markus; Nelin, Timothy D.; Youtz, Dane J.; Sun, Qinghua

    2014-01-01

    Exposure to ambient air pollution contributes to the progression of cardiovascular disease, particularly in susceptible populations. The objective of the present study was to determine whether early life exposure to air pollution causes persistent cardiovascular consequences measured at adulthood. Pregnant FVB mice were exposed to filtered (FA) or concentrated ambient particulate matter (PM2.5) during gestation and nursing. Mice were exposed to PM2.5 at an average concentration of 51.69 μg/m3 from the Columbus, OH region for 6 h/day, 7 days/wk in utero until weaning at 3 wk of age. Birth weight was reduced in PM2.5 pups compared with FA (1.36 ± 0.12 g FA, n = 42 mice; 1.30 ± 0.15 g PM2.5, n = 67 P = 0.012). At adulthood, mice exposed to perinatal PM2.5 had reduced left ventricular fractional shortening compared with FA-exposed mice (43.6 ± 2.1% FA, 33.2 ± 1.6% PM2.5, P = 0.001) with greater left ventricular end systolic diameter. Pressure-volume loops showed reduced ejection fraction (79.1 ± 3.5% FA, 35.5 ± 9.5% PM2.5, P = 0.005), increased end-systolic volume (10.4 ± 2.5 μl FA, 39.5 ± 3.8 μl PM2.5, P = 0.001), and reduced dP/dt maximum (11,605 ± 200 μl/s FA, 9,569 ± 800 μl/s PM2.5, P = 0.05) and minimum (−9,203 ± 235 μl/s FA, −7,045 ± 189 μl/s PM2.5, P = 0.0005) in PM2.5-exposed mice. Isolated cardiomyocytes from the hearts of PM2.5-exposed mice had reduced peak shortening (%PS, 8.53 ± 2.82% FA, 6.82 ± 2.04% PM2.5, P = 0.003), slower calcium reuptake (τ, 0.22 ± 0.09 s FA, 0.26 ± 0.07 s PM2.5, P = 0.048), and reduced response to β-adrenergic stimulation compared with cardiomyocytes isolated from mice that were exposed to FA. Histological analyses revealed greater picro-sirius red-positive-stained areas in the PM2.5 vs. FA group, indicative of increased collagen deposition. We concluded that these data demonstrate the detrimental role of early life exposure to ambient particulate air pollution in programming of adult cardiovascular

  10. In vitro mucus transportability, cytogenotoxicity, and hematological changes as non-destructive physiological biomarkers in fish chronically exposed to metals.

    PubMed

    Seriani, Robson; Abessa, Denis M S; Moreira, Lucas B; Cabrera, Joana P G; Sanches, Juliana Q; Silva, Carolina L S; Amorim, Francisca A; Rivero, Dolores H R F; Silva, Flavia L; Fitorra, Lilian S; Carvalho-Oliveira, Regiani; Macchione, Mariangela; Ranzani-Paiva, Maria J T

    2015-02-01

    The biomonitoring of fish using biomarkers represents a useful tool for the assessment of aquatic pollution. This study evaluated the sublethal toxic effects of aquatic pollution on fish collected from a site contaminated by metals. Water and fish (Oreochromis niloticus) samples were collected from a pond in the Parque Ecológico do Tietê (PET) that lies along the Tietê River (São Paulo, Brazil), and from a control site (an experimental fish farm). The metal content of the water was evaluated, and fish were used to examine the properties of gill mucus and blood. The PET fish were evaluated for alterations in the in vitro transportability of mucus and changes in blood properties (e.g., cell volume, hemoglobin concentration, red blood cells, and white blood cell count). The results of the water analyzes indicated metal levels above the legal standards for Fe (0.71 mg/L), Ni (0.06 mg/L), Mn (0.11 mg/L), and Pb (0.48 mg/L). Compared to the controls, the hematologic parameter analyzes of PET fish revealed significantly higher numbers of erythrocytes (RBC), leukocytes (WBC), lymphocytes, erythroblasts, and Mean Corpuscular Volume (MCV); however, the hemoglobin content and Mean Corpuscular Hemoglobin Concentration (MCHC) values were significantly lower. The frequencies of nuclear abnormalities and micronuclei were significantly higher and the mucociliary transport was significantly lower in PET fish than in the controls. These results suggest that fish from the contaminated site exhibit a series of physiological responses, which probably indicate health disturbances. Furthermore, the results suggest that blood and mucus are promising, non-destructive targets for use in the monitoring of pollution. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. APPROACH TO ESTIMATING PARTICIPANT POLLUTANT EXPOSURES IN THE MULTI-ETHNIC STUDY OF ATHEROSCLEROSIS AND AIR POLLUTION (MESA AIR)

    PubMed Central

    Cohen, Martin A.; Adar, Sara D.; Allen, Ryan W.; Avol, Edward; Curl, Cynthia L.; Gould, Timothy; Hardie, David; Ho, Anne; Kinney, Patrick; Larson, Timothy V.; Sampson, Paul; Sheppard, Lianne; Stukovsky, Karen D.; Swan, Susan S.; Liu, L-J Sally; Kaufman, Joel D.

    2009-01-01

    Most published epidemiology studies of long-term air pollution health effects have relied on central site monitoring to investigate regional-scale differences in exposure. Few cohort studies have had sufficient data to characterize localized variations in pollution, despite the fact that large gradients can exist over small spatial scales. Similarly, previous data have generally been limited to measurements of particle mass or several of the criteria gases. The Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air) is an innovative investigation undertaken to link subclinical and clinical cardiovascular health effects with individual-level estimates of personal exposure to ambient-origin pollution. This project improves on prior work by implementing an extensive exposure assessment program to characterize long-term average concentrations of ambient-generated PM2.5, specific PM2.5 chemical components, and co-pollutants, with particular emphasis on capturing concentration gradients within cities. This paper describes exposure assessment in MESA Air, including questionnaires, community sampling, home monitoring, and personal sampling. Summary statistics describing the performance of the sampling methods are presented along with descriptive statistics of the air pollution concentrations by city. PMID:19673252

  12. Non-destructive testing on aramid fibres for the long-term assessment of interventions on heritage structures

    NASA Astrophysics Data System (ADS)

    Ceravolo, R.; De Marchi, A.; Pinotti, E.; Surace, C.; Zanotti Fragonara, L.

    2015-07-01

    High strength fibre reinforced polymers (FRPs) are composite materials made of fibres such as carbon, aramid and/or glass, and a resin matrix. FRPs are commonly used for structural repair and strengthening interventions and exhibit high potential for applications to existing constructions, including heritage buildings. In regard to aramid fibres, uncertainties about the long-term behaviour of these materials have often made the designers reluctant to use them in structural engineering. The present study describes simple and non-destructive nonlinearity tests for assessing damage or degradation of structural properties in Kevlar fibres. This was obtained by using high precision measurements to detect small deviations in the dynamic response measured on fibres and ropes. The change in dynamic properties was then related to a damage produced by exposure of the sample to UV rays for a defined time period, which simulated long-term sun exposure. In order to investigate the sensitivity of such an approach to damage detection, non-linearity characterisation tests were conducted on aramid fibres in both damaged and undamaged states. With the purpose of carrying out dynamic tests on small fibre specimens, a dedicated instrumentation was designed and built in cooperation with the Metrology Laboratory of the Department of Electronics at the Politecnico di Torino.

  13. Before the first breath: prenatal exposures to air pollution and lung development.

    PubMed

    Veras, Mariana Matera; de Oliveira Alves, Nilmara; Fajersztajn, Lais; Saldiva, Paulo

    2017-03-01

    Various environmental contaminants are known to impair the growth trajectories of major organs, indirectly (gestational exposure) or directly (postnatal exposure). Evidence associates pre-gestational and gestational exposure to air pollutants with adverse birth outcomes (e.g., low birth weight, prematurity) and with a wide range of diseases in childhood and later in life. In this review, we explore the way that pre-gestational and gestational exposure to air pollution affects lung development. We present results in topics underlining epidemiological and toxicological evidence. We also provide a summary of the biological mechanisms by which air pollution exposure possibly leads to adverse respiratory outcomes. We conclude that gestational and early life exposure to air pollutants are linked to alterations in lung development and function and to other negative respiratory conditions in childhood (wheezing, asthma) that may last into adulthood. Plausible mechanisms encompass changes in maternal physiology (e.g., hypoxia, oxidative stress and inflammation) and DNA alterations in the fetus. Evidence for pre-gestational and gestational effects on the lung is scarce compared with that on early life exposure and further studies are needed. However, the suggested mechanisms are credible and the evidence of pre-gestational and gestational air pollution exposure is robust for adverse birth outcomes. Air pollutants might change lung developmental trajectories of the unborn child predisposing it to diseases later in life highlighting the urgent need for controls on urban air pollution levels worldwide.

  14. A Comparison of Exposure Metrics for Traffic-Related Air Pollutants: Application to Epidemiology Studies in Detroit, Michigan

    EPA Science Inventory

    Vehicles are major sources of air pollutant emissions, and individuals living near large roads endure high exposures and health risks associated with traffic-related air pollutants. Air pollution epidemiology, health risk, environmental justice, and transportation planning studi...

  15. A Comparison of Exposure Metrics for Traffic-Related Air Pollutants: Application to Epidemiology Studies in Detroit, Michigan

    EPA Science Inventory

    Vehicles are major sources of air pollutant emissions, and individuals living near large roads endure high exposures and health risks associated with traffic-related air pollutants. Air pollution epidemiology, health risk, environmental justice, and transportation planning studi...

  16. Non-destructive Assessment of Engineered Cartilage Composition by Near Infrared Spectroscopy

    PubMed Central

    McGoverin, Cushla M.; Hanifi, Arash; Palukuru, Uday P.; Yousefi, Farzad; Glenn, Padraig B. M.; Shockley, Michael; Spencer, Richard G.; Pleshko, Nancy

    2016-01-01

    Tissue engineering presents a strategy to overcome the limitations of current tissue healing methods. Scaffolds, cells, external growth factors and mechanical input are combined in an effort to obtain constructs with properties that mimic native tissues. However, engineered constructs developed using similar culture environments can have very different matrix composition and biomechanical properties. Accordingly, a non-destructive technique to assess constructs during development such that appropriate compositional endpoints can be defined is desirable. Near infrared spectroscopy (NIRS) analysis is a modality being investigated to address the challenges associated with current evaluation techniques, which includes non-destructive compositional assessment. In the present study, cartilage tissue constructs were grown using chondrocytes seeded onto polyglycolic acid (PGA) scaffolds in similar environments in three separate tissue culture experiments and monitored using NIRS. Multivariate partial least squares (PLS) analysis models of NIR spectra were calculated and used to predict tissue composition, with biochemical assay information used as the reference data. Results showed that for combined data from all tissue culture experiments, PLS models were able to assess composition with significant correlations to reference values, including engineered cartilage water (at 5200 cm−1, R = 0.68, p = 0.03), proteoglycan (at 4310 cm−1, R = 0.82, p = 0.007), and collagen (at 4610 cm−1, R = 0.84, p = 0.005). In addition, degradation of PGA was monitored using specific NIRS frequencies. These results demonstrate that NIR spectroscopy combined with multivariate analysis provides a non-destructive modality to assess engineered cartilage, which could provide information to determine the optimal time for tissue harvest for clinical applications. PMID:26817457

  17. A Monte Carlo approach applied to ultrasonic non-destructive testing

    NASA Astrophysics Data System (ADS)

    Mosca, I.; Bilgili, F.; Meier, T.; Sigloch, K.

    2012-04-01

    Non-destructive testing based on ultrasound allows us to detect, characterize and size discrete flaws in geotechnical and architectural structures and materials. This information is needed to determine whether such flaws can be tolerated in future service. In typical ultrasonic experiments, only the first-arriving P-wave is interpreted, and the remainder of the recorded waveform is neglected. Our work aims at understanding surface waves, which are strong signals in the later wave train, with the ultimate goal of full waveform tomography. At present, even the structural estimation of layered media is still challenging because material properties of the samples can vary widely, and good initial models for inversion do not often exist. The aim of the present study is to combine non-destructive testing with a theoretical data analysis and hence to contribute to conservation strategies of archaeological and architectural structures. We analyze ultrasonic waveforms measured at the surface of a variety of samples, and define the behaviour of surface waves in structures of increasing complexity. The tremendous potential of ultrasonic surface waves becomes an advantage only if numerical forward modelling tools are available to describe the waveforms accurately. We compute synthetic full seismograms as well as group and phase velocities for the data. We invert them for the elastic properties of the sample via a global search of the parameter space, using the Neighbourhood Algorithm. Such a Monte Carlo approach allows us to perform a complete uncertainty and resolution analysis, but the computational cost is high and increases quickly with the number of model parameters. Therefore it is practical only for defining the seismic properties of media with a limited number of degrees of freedom, such as layered structures. We have applied this approach to both synthetic layered structures and real samples. The former contributed to benchmark the propagation of ultrasonic surface

  18. Research Performed within the Non-Destructive Evaluation Team at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Burns, Erin A.

    2004-01-01

    Non-destructive testing is essential in many fields of manufacturing and research in order to perform reliable examination of potentially damaged materials and parts without destroying the inherent structure of the materials. Thus, the Non-Destructive Evaluation (NDE) Team at NASA Glenn Research Center partakes in various projects to improve materials testing equipment as well as analyze materials, material defects, and material deficiencies. Due to the array of projects within the NDE Team at this time, five research aims were supplemental to some current projects. A literature survey of "DE and testing methodologies as related to rocks was performed. Also, Mars Expedition Rover technology was assessed to understand the requirements for instrumentation in harsh space environments (e.g. temperature). Potential instrumentation and technologies were also considered and documented. The literature survey provided background and potential sources for a proposal to acquire funding for ultrasonic instrumentation on board a future Mars expedition. The laboratory uses a Santec Systems AcousticScope AS200 acoustography system. Labview code was written within the current program in order to improve the current performance of the acoustography system. A sample of Reinforced Carbon/Carbon (RCC) material from the leading edge of the space shuttle underwent various non-destructive tests (guided wave scanning, thermography, computed tomography, real time x-ray, etc.) in order to characterize its structure and examine possible defects. Guided wave scan data of a ceramic matrix composite (CMC) panel was reanalyzed utilizing image correlations and signal processing variables. Additional guided wave scans and thermography were also performed on the CMC panel. These reevaluated data and images will be used in future presentations and publications. An additional axis for the guided wave scanner was designed, constructed, and implemented. This additional axis allowed incremental spacing

  19. Non-destructive estimation of foliar carotenoid content of tree species using merged vegetation indices.

    PubMed

    Fassnacht, Fabian E; Stenzel, Stefanie; Gitelson, Anatoly A

    2015-03-15

    Leaf pigment content is an important indicator of plant status and can serve to assess the vigor and photosynthetic activity of plants. The application of spectral information gathered from laboratory, field and remote sensing-based spectrometers to non-destructively assess total chlorophyll (Chl) content of higher plants has been demonstrated in earlier studies. However, the precise estimation of carotenoid (Car) content with non-destructive spectral measurements has so far not reached accuracies comparable to the results obtained for Chl content. Here, we examined the potential of a recently developed angular vegetation index (AVI) to estimate total foliar Car content of three tree species. Based on an iterative search of all possible band combinations, we identified a best candidate AVIcar. The identified index showed quite close but essentially not linear relation with Car contents of the examined species with increasing sensitivity to high Car content and a lack of sensitivity to low Car content for which earlier proposed vegetation indices (VI) performed better. To make use of the advantages of both VI types, we developed a simple merging procedure, which combined the AVIcar with two earlier proposed carotenoid indices. The merged indices had close linear relationship with total Car content and outperformed all other examined indices. The merged indices were able to accurately estimate total Car content with a percental root mean square error (%RMSE) of 8.12% and a coefficient of determination of 0.88. Our findings were confirmed by simulations using the radiative transfer model PROSPECT-5. For simulated data, the merged indices again showed a quasi linear relationship with Car content. This strengthens the assumption that the proposed merged indices have a general ability to accurately estimate foliar Car content. Further examination of the proposed merged indices to estimate foliar Car content of other plant species is desirable to prove the general

  20. Evaluation of Mechanical Properties of Nuclear Materials Using Non-Destructive Ball Indentation Technique

    SciTech Connect

    Mathew, M.D.; Linga Murty, K.

    2002-07-01

    Integrity of structural components depends on the deformation and fracture behavior of materials. For evaluating the material condition in-service, it is generally not feasible or practical or advisable to cut samples from operating structures. Non-destructive testing (NDT) techniques are required to evaluate the mechanical properties. Although several NDT techniques such as ultrasound, magnetic strength, Barkhausen noise, microhardness etc., are employed for estimating the mechanical property degradation, these methodologies are generally empirical and indirect. Automated Ball Indentation (ABI) is a non-destructive testing technique for direct measurement of mechanical and fracture properties of metallic engineering materials. Because of the small area over which the test is carried out, it is possible to determine point to point variations in the mechanical and fracture properties, such as those that exist in weldments. Although ABI technique is non-intrusive, it is a state-of-the-art mechanical test that measures directly the current/local deformation behavior of the material. In this paper, we present results from studies on the application of ABI technique to determine tensile and fracture properties of ferritic steels, an austenitic stainless steel, a nickel base superalloy and Zircaloy in different thermo-mechanical conditions. The effects of aging and cold work on these properties were determined from the ABI tests. Gradients in mechanical properties of ferritic steel welds, particularly in the narrow heat-affected zone, were clearly established. ABI technique was found to be useful in determining the anisotropy in the tensile properties of Zircaloy cladding tubes. The technique has potential as a non-destructive method for assessing structural integrity of aged components. (authors)

  1. [Method of ecological risk assessment for risk pollutants under short-term and high dose exposure in water pollution accident].

    PubMed

    Lei, Bing-Li; Sun, Yan-Feng; Liu, Qian; Yu, Zhi-Qiang; Zeng, Xiang-Ying

    2011-11-01

    In recent years, water pollution accidents resulting in acute aquatic ecological risk and security issues become a research focus. However, in our country, the surface water quality standards and drinking water health standards were used to determine the safety of waters or not in pollution incidents due to lacking safety effect threshold or risk value for protection of aquatic life. In foreign countries, although predicted no effect concentration (PNEC) or risk value (R) of pollutants were provided for protection of aquatic organisms, the PNECs or risk values were derived based on long-term exposure toxicity data NOECs (no observed effect concentrations) and lack of short-term exposure risk or threshold values. For the short-term and high dose exposure in pollution incident, ecological risk assessment methods were discussed according to the procedures of the conventional ecological risk assessment and the water quality criteria establishment of the U.S. EPA for the protection of aquatic organisms in short-term exposure, and had a case study. At the same time, we provide some suggestions for the establishment of ecological risk assessment system in water pollution incidents.

  2. Fast Non-Destructive Evaluation of Superconducting Magnet Wires using a Flow-Through SQUID Microscope

    NASA Astrophysics Data System (ADS)

    Matthews, John; Wellstood, Frederick; Weinstock, Harold

    2006-03-01

    We have developed a cryocooled high-Tc SQUID microscope for fast non-destructive evaluation (NDE) of long wires, designed for detecting defects in superconducting magnet wire. A feedthrough mechanism pulls the wire at speeds of up to 20 cm/s through a thin mylar tube that separates the room temperature wire from the SQUID. We present results on test wires where we detect defects down to about 0.3 mm diameter. We discuss how we extract information from the data, such as defect size and location, and also outline a method for fast automated detection of defects in long wires.

  3. Non-destructive Testing by Infrared Thermography Under Random Excitation and ARMA Analysis

    NASA Astrophysics Data System (ADS)

    Bodnar, J. L.; Nicolas, J. L.; Candoré, J. C.; Detalle, V.

    2012-11-01

    Photothermal thermography is a non-destructive testing (NDT) method, which has many applications in the field of control and characterization of thin materials. This technique is usually implemented under CW or flash excitation. Such excitations are not adapted for control of fragile materials or for multi-frequency analysis. To allow these analyses, in this article, the use of a new control mode is proposed: infrared thermography under random excitation and auto regressive moving average analysis. First, the principle of this NDT method is presented. Then, the method is shown to permit detection, with low energy constraints, of detachments situated in mural paintings.

  4. Delayed Gamma-ray Spectroscopy for Non-Destructive Assay of Nuclear Materials

    SciTech Connect

    Mozin, Vladimir; Ludewigt, Bernhard; Campbell, Luke; Favalli, Andrea; Hunt, Alan

    2014-10-09

    This project addresses the need for improved non-destructive assay techniques for quantifying the actinide composition of spent nuclear fuel and for the independent verification of declared quantities of special nuclear materials at key stages of the fuel cycle. High-energy delayed gamma-ray spectroscopy following neutron irradiation is a potential technique for directly assaying spent fuel assemblies and achieving the safeguards goal of quantifying nuclear material inventories for spent fuel handling, interim storage, reprocessing facilities, repository sites, and final disposal. Other potential applications include determination of MOX fuel composition, characterization of nuclear waste packages, and challenges in homeland security and arms control verification.

  5. Application of magnetic resonance imaging to non-destructive void detection in watermelon

    NASA Astrophysics Data System (ADS)

    Saito, K.; Miki, T.; Hayashi, S.; Kajikawa, H.; Shimada, M.; Kawate, Y.; Nishizawa, T.; Ikegaya, D.; Kimura, N.; Takabatake, K.; Sugiura, N.; Suzuki, M.

    A novel application of magnetic resonance imaging (MRI) is described. The possibility of utilizing MRI for non-destructive quality evaluation of watermelons was studied. In this study, we applied MRI to the detection of internal voids in watermelons. In order to increase the measurement rate, we employed a one-dimensional projection profile method instead of observing a two-dimensional cross-sectional image. The void detection was carried out with this technique over 30 samples and 28 samples were correctly evaluated. The measurement rate was 900 ms per sample, which is an acceptable speed for a sorting machine in the agricultural field.

  6. Non-destructive testing of biaxial stress state in ferromagnetic materials

    NASA Astrophysics Data System (ADS)

    Vengrinovich, V. L.; Vintov, D. A.; Dmitrovich, D. V.

    2014-02-01

    The technique for biaxial stress state quantitative non destructive testing using magnetic, namely Barkhausen Noise, measurements is developed and checked experimentally. The main elaboration concerns the application of uni-axial calibration data for bi-axial stress measurement in the material which treatment pre-history is not definitely known. The article is aimed to get over difficulties, accompanying factual nondestructive stress evaluation, implied from its tensor nature. The developed technique of stress calibration and measurement assumes the bi-axial stress components recovery from uni-axial magnetic and Barkhausen noise measurement results. The complete technology, based on new calibration procedure with grid diagrams is considered in the article.

  7. Non-Destructive Testing with Atmospheric Pressure Radio-Frequency Plasma

    NASA Astrophysics Data System (ADS)

    May, A.; Andarawis, E.

    2007-03-01

    We summarize our recent work using radio-frequency (RF) atmospheric pressure plasma (APP) for non-destructive evaluation (NDE), specifically for: (1) Clearance sensing (0-5mm) on rotating components, and (2) Generation of broadband ultrasound in air at 900kHz. RF-APP showed potential in both of these common NDE requirements, but further work is required to better characterize and optimize the performance of the new techniques. Application of RF-APP to other NDE disciplines, such as plasma spectroscopy and gas flow measurement, is also likely to be advantageous, especially in harsh environments where existing approaches are prohibitively expensive or complex.

  8. [NIR spectrometer for non-destruction measurement of oil contents in a corn seed].

    PubMed

    Cui, Zhi-li; Xie, Jin-chun; Wang, Nan; Pan, Ling-ling; Song, Tong-ming; Zhang, Ye-hui; Xu, Xiao-jie

    2005-11-01

    NIR spectromneter for non-destruction measurement of oil contents in an integrated kernel of corn was manufactured. Using LED (light emitting diode) as the light source and six filters as the monochromator, the specifications of the instrument are compared with those of the commercial instruments. The regression coefficient, the standard error, and the relative error of measuring oil contents in an integrated kernel of corn are 0.9688, 0.72 and 0.062 respectively. The results meet the demand of high-oil corn breeding.

  9. Methods for Non-destructive Temperature Measurements in a Magneto-Optical Trap

    NASA Astrophysics Data System (ADS)

    Narducci, Frank A.; Duncan, Dwight; White, Grady R.; Lough, James; Davis, Jon P.

    2009-05-01

    Certain practical applications for precision measurements by atom interferometers require knowledge of the input atom cloud's temperature from realization to realization. Recent work [1,2] has shown how to measure the temperature of atoms in a magneto-optical trap in a non-destructive, in situ manner. We discuss an alternate, simpler method for the nondestructive measurement of the temperature of an atom cloud and compare our method with earlier techniques. [4pt] [1] T. Brzozowski, M. Brzozowska, J. Zachorowski, M. Zawada, W. Gawlik, PRA, 71, 013401 (2005).[0pt] [2] M. Brzozowska, T. Brzozowski J. Zachorowski, W. Gawlik, PRA, 72, 061401(R), (2005).

  10. Homeland Security, Medical, Pharmaceutical and Non-destructive Testing Applications of Terahertz Radiation

    NASA Astrophysics Data System (ADS)

    Kemp, Michael

    2005-03-01

    The terahertz region of the electromagnetic spectrum (300GHz-10THz) spans the region between radio and light. Recent advances in terahertz source, detector and systems technology are enabling new applications across a number of fields, based on both terahertz imaging and spectroscopy. This paper reviews our recent work on the development of practical systems and applications in security screening for the detection of explosives and non-metallic weapons; in medical imaging for cancer detection; as well as applications in non-destructive testing and the pharmaceutical industry.

  11. Non-destructive qualification tests for ITER cryogenic axial insulating breaks

    SciTech Connect

    Kosek, Jacek; Lopez, Roberto; Tommasini, Davide; Rodriguez-Mateos, Felix

    2014-01-29

    In the ITER superconducting magnets the dielectric separation between the CICC (Cable-In-Conduit Conductors) and the helium supply pipes is made through the so-called insulating breaks (IB). These devices shall provide the required dielectric insulation at a 30 kV level under different types of stresses and constraints: thermal, mechanical, dielectric and ionizing radiations. As part of the R and D program, the ITER Organization launched contracts with industrial companies aimed at the qualification of the manufacturing techniques. After reviewing the main functional aspects, this paper describes and discusses the protocol established for non-destructive qualification tests of the prototypes.

  12. Non-destructive terahertz imaging of illicit drugs using spectral fingerprints

    NASA Astrophysics Data System (ADS)

    Kawase, Kodo; Ogawa, Yuichi; Watanabe, Yuuki; Inoue, Hiroyuki

    2003-10-01

    The absence of non-destructive inspection techniques for illicit drugs hidden in mail envelopes has resulted in such drugs being smuggled across international borders freely. We have developed a novel basic technology for terahertz imaging, which allows detection and identification of drugs concealed in envelopes, by introducing the component spatial pattern analysis. The spatial distributions of the targets are obtained from terahertz multispectral transillumination images, using absorption spectra measured with a tunable terahertz-wave source. The samples we used were methamphetamine and MDMA, two of the most widely consumed illegal drugs in Japan, and aspirin as a reference.

  13. The development of non destructive remote measurement method of concrete contamination

    SciTech Connect

    Stepanov, V E; Potapov, V N; Ivanov, O P

    2013-07-01

    In the frame of the decommissioning of nuclear power plants or laboratories, the penetration depth of the contamination in concrete surfaces: walls, floor, is unknown. Its knowledge requires sample analysis, that is time consuming and expensive. The main goal of the work is to define and evaluate a non-destructive measurement technique for the evaluation of the contamination depth in concrete. Estimation of accuracy of measurements for different contamination levels, time of measurement, value of natural radionuclides (NRN) concentration in concrete and background radiation dose were carried out. The type of relevant detector depends of selected limiting sensitivity, the weight and sizes of the device. (authors)

  14. Non-Destructive Evaluation Method and Apparatus for Measuring Acoustic Material Nonlinearity

    NASA Technical Reports Server (NTRS)

    Yost, William T. (Inventor); Cantrell, John H. (Inventor)

    2002-01-01

    An acoustic non-linearity parameter (beta) measurement method and system for Non-Destructive Evaluation (NDE) of materials and structural members obviates the need for electronic calibration of the measuring equipment. Unlike known substitutional measuring techniques requiring elaborate calibration procedures, the electrical outputs of the capacitive detector of a sample with known beta and the test sample of unknown beta are compared to determine the unknown beta. In order to provide the necessary stability of the present-inventive reference-based approach, the bandpass filters of the measurement system are maintained in a temperature-controlled environment, and the line voltage supplied to said amplifiers is well-regulated.

  15. Computed tomography for non-destructive evaluation of composites: Applications and correlations

    NASA Technical Reports Server (NTRS)

    Goldberg, B.; Hediger, L.; Noel, E.

    1985-01-01

    The state-of-the-art fabrication techniques for composite materials are such that stringent species-specific acceptance criteria must be generated to insure product reliability. Non-destructive evaluation techniques including computed tomography (CT), X-ray radiography (RT), and ultrasonic scanning (UT) are investigated and compared to determine their applicability and limitations to graphite epoxy, carbon-carbon, and carbon-phenolic materials. While the techniques appear complementary, CT is shown to provide significant, heretofore unattainable data. Finally, a correlation of NDE techniques to destructive analysis is presented.

  16. Magnetic non-destructive evaluation of hardening of cold rolled reactor pressure vessel steel

    NASA Astrophysics Data System (ADS)

    Wang, Xuejiao; Qiang, Wenjiang; Shu, Guogang

    2017-08-01

    Non-destructive test (NDT) of reactor pressure vessel (RPV) steel is urgently required due to the life extension program of nuclear power plant. Here magnetic NDT of cold rolled RPV steel is studied. The strength, hardness and coercivity increase with the increasing deformation, and a good linear correlation between the increment of coercivity, hardness and yield strength is found, which may be helpful to develop magnetic NDT of degradation of RPV steel. It is also found that besides dislocation density, the distribution of dislocations may affect coercivity as well.

  17. Application of golay complementary coded excitation schemes for non-destructive testing of sandwich structures

    NASA Astrophysics Data System (ADS)

    Arora, Vanita; Mulaveesala, Ravibabu

    2017-06-01

    In recent years, InfraRed Thermography (IRT) has become a widely accepted non-destructive testing technique to evaluate the structural integrity of composite sandwich structures due to its full-field, remote, fast and in-service inspection capabilities. This paper presents a novel infrared thermographic approach named as Golay complementary coded thermal wave imaging is presented to detect disbonds in a sandwich structure having face sheets from Glass/Carbon Fibre Reinforced (GFR/CFR) laminates and core of the wooden block.

  18. Additive Manufacturing (AM) Activities and Non-Destructive Evaluation (NDE) at GSFC

    NASA Technical Reports Server (NTRS)

    Jones, Justin S.

    2017-01-01

    NASA personnel will be meeting with a delegation from the Japan Aerospace Exploration Agency (JAXA) Office of Safety and Mission Assurance (OSMA) at Langley Research Center on 2217 through 3217. The purpose of the meeting is a technical interchange between NASA and JAXA to discuss Non-Destructive Evaluation (NDE) of Additive Manufacturing (AM) parts and the HALT process (relates to accelerated life testing). The visitors will be a small group of Japanese citizens. Goddard Space Flight Center (GSFC) has been asked to participate in the meeting, either in person or via teleconference. This presentation covers NDE efforts at GSFC and provides a cursory overview of AM and lab capabilities.

  19. Application of alternative spatiotemporal metrics of ambient air pollution exposure in a time-series epidemiological study in Atlanta

    EPA Science Inventory

    Exposure error in studies of ambient air pollution and health that use city-wide measures of exposure may be substantial for pollutants that exhibit spatiotemporal variability. Alternative spatiotemporal metrics of exposure for traffic-related and regional pollutants were applied...

  20. Application of alternative spatiotemporal metrics of ambient air pollution exposure in a time-series epidemiological study in Atlanta

    EPA Science Inventory

    Exposure error in studies of ambient air pollution and health that use city-wide measures of exposure may be substantial for pollutants that exhibit spatiotemporal variability. Alternative spatiotemporal metrics of exposure for traffic-related and regional pollutants were applied...

  1. Exposure prediction approaches used in air pollution epidemiology studies: Keyfindings and future recommendations

    EPA Science Inventory

    Many epidemiologic studies of the health effects of exposure to ambient air pollution use measurements from central-site monitors as their exposure estimate. However, measurements from central-site monitors may lack the spatial and temporal resolution required to capture exposure...

  2. Case report: Atrial fibrillation following exposure to ambient air pollution particles

    EPA Science Inventory

    CONTEXT: Exposure to air pollution can result in the onset of atrial fibrillation. CASE PRESENTATION: We present a case of a 58 year old woman who volunteered to participate in a controlled exposure to concentrated ambient particles (CAPs). Twenty minutes into the exposure, there...

  3. Exposure prediction approaches used in air pollution epidemiology studies: Keyfindings and future recommendations

    EPA Science Inventory

    Many epidemiologic studies of the health effects of exposure to ambient air pollution use measurements from central-site monitors as their exposure estimate. However, measurements from central-site monitors may lack the spatial and temporal resolution required to capture exposure...

  4. Case report: Atrial fibrillation following exposure to ambient air pollution particles

    EPA Science Inventory

    CONTEXT: Exposure to air pollution can result in the onset of atrial fibrillation. CASE PRESENTATION: We present a case of a 58 year old woman who volunteered to participate in a controlled exposure to concentrated ambient particles (CAPs). Twenty minutes into the exposure, there...

  5. EXPOSURE VERSION 2 - A COMPUTER MODEL FOR ANALYZING THE EFFECTS OF INDOOR AIR POLLUTANT SOURCES ON INDIVIDUAL EXPOSURE

    EPA Science Inventory

    The report presents a model for calculating individual exposure to indoor pollutants from sources. The model calculates exposure due to individual, as opposed to population, activity patterns and source use. The model uses data on source emissions, room- to- room air flows, air e...

  6. Development and evaluation of alternative approaches for exposure assessment of multiple air pollutants in Atlanta, Georgia.

    PubMed

    Dionisio, Kathie L; Isakov, Vlad; Baxter, Lisa K; Sarnat, Jeremy A; Sarnat, Stefanie Ebelt; Burke, Janet; Rosenbaum, Arlene; Graham, Stephen E; Cook, Rich; Mulholland, James; Özkaynak, Halûk

    2013-01-01

    Measurements from central site (CS) monitors are often used as estimates of exposure in air pollution epidemiological studies. As these measurements are typically limited in their spatiotemporal resolution, true exposure variability within a population is often obscured, leading to potential measurement errors. To fully examine this limitation, we developed a set of alternative daily exposure metrics for each of the 169 ZIP codes in the Atlanta, GA, metropolitan area, from 1999 to 2002, for PM(2.5) and its components (elemental carbon (EC), SO(4)), O(3), carbon monoxide (CO), and nitrogen oxides (NOx). Metrics were applied in a study investigating the respiratory health effects of these pollutants. The metrics included: (i) CS measurements (one CS per pollutant); (ii) air quality model results for regional background pollution; (iii) local-scale AERMOD air quality model results; (iv) hybrid air quality model estimates (a combination of (ii) and (iii)); and (iv) population exposure model predictions (SHEDS and APEX). Differences in estimated spatial and temporal variability were compared by exposure metric and pollutant. Comparisons showed that: (i) both hybrid and exposure model estimates exhibited high spatial variability for traffic-related pollutants (CO, NO(x), and EC), but little spatial variability among ZIP code centroids for regional pollutants (PM(2.5), SO(4), and O(3)); (ii) for all pollutants except NO(x), temporal variability was consistent across metrics; (iii) daily hybrid-to-exposure model correlations were strong (r>0.82) for all pollutants, suggesting that when temporal variability of pollutant concentrations is of main interest in an epidemiological application, the use of estimates from either model may yield similar results; (iv) exposure models incorporating infiltration parameters, time-location-activity budgets, and other exposure factors affect the magnitude and spatiotemporal distribution of exposure, especially for local pollutants. The

  7. PREFACE: III All-Russian Scientific and Practical Conference on Innovations in Non-Destructive Testing (SibTest 2015)

    NASA Astrophysics Data System (ADS)

    2016-01-01

    This issue of the journal is devoted to the research and studies presented at the III All-Russian Scientific and Practical Conference on Innovations in Non-Destructive Testing SibTest. The conference was held in Altai, Russia, on 27-31 July 2015. The conference brought together experts from different countries and organizations who had a great opportunity to share knowledge during oral and poster presentations and to initiate discussions on topics that are of interest to the conference attendees. The conference aimed to discuss innovative methods and the application of advanced technologies in non-destructive testing. The conference also attempted to bring together university, academic and industrial science, to expand the co-operation of scientists from different countries in research and development and the commercialization of innovative technologies in non-destructive testing. The key themes of the conference were: ultrasonic and acoustic testing; electromagnetic and thermal testing; various types of radiation non-destructive testing; passive and active testing techniques. The conference organizers are the Institute of Non-Destructive Testing, Tomsk Polytechnic University, with the assistance of the Russian Society for Non-Destructive Testing and Technical Diagnostics, Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences, National Research Tomsk State University, Moscow State Institute of Radio Engineering, Electronics and Automation.

  8. Personal exposure to particulate air pollution in transport microenvironments

    NASA Astrophysics Data System (ADS)

    Gulliver, J.; Briggs, D. J.

    Personal measurements of exposure to particulate air pollution (PM 10, PM 2.5, PM 1) were simultaneously made during walking and in-car journeys on two suburban routes in Northampton, UK, during the winter of 1999/2000. Comparisons were made between concentrations found in each transport mode by particle fraction, between different particle fractions by transport mode, and between transport microenvironments and a fixed-site monitor located within the study area. High levels of correlation were seen between walking and in-car concentrations for each of the particle fractions (PM 10: r2=0.82; PM 2.5: r2=0.98; PM 1: r2=0.99). On an average, PM 10 concentrations were 16% higher inside the car than for the walker, but there were no difference in average PM 2.5 and PM 1 concentrations between the two modes. High PM 2.5:PM 10 ratios (0.6-0.73) were found to be associated with elevated sulphate levels. The PM 2.5:PM 10 and PM 1:PM 2.5 ratios were shown to be similar between walking and in-car concentrations. Concentrations of PM 10 were found to be more closely related between transport mode than either mode was with concentrations recorded at the fixed-site (roadside) monitor. The fixed-site monitor was shown to be a poor marker for PM 10 concentrations recorded during walking and in-car on a route over 1 km away.

  9. Exposure and inequality for select urban air pollutants in the Tampa Bay area.

    PubMed

    Yu, Haofei; Stuart, Amy L

    2016-05-01

    Air pollution exposure has been linked to numerous adverse health effects, with some disadvantaged subgroups disproportionately burdened. The objective of this work was to characterize distributions of emissions and concentrations of a few important urban air toxics at high spatiotemporal resolution in order to assess exposure and inequality. Benzene, 1,3-butadiene, formaldehyde, and acetaldehyde were the focus pollutants, with oxides of nitrogen (NOx) estimated for comparisons. Primary pollutant emissions were estimated for the full spectrum of source types in the Tampa area using a hybrid approach that is most detailed for major roadways and includes hourly variations in vehicle speed. Resultant pollutant concentrations were calculated using the CALPUFF dispersion model, and combined with CMAQ model output to account for secondary formation of formaldehyde and acetaldehyde. Census demographic data were applied to estimate residential pollution exposures and inequality among population subgroups. Estimated concentrations of benzene, 1,3-butadiene, and NOx were generally higher in urban areas and lower in rural areas. Exposures to these pollutants were disproportionately high for subgroups characterized as black, Hispanic and low income (annual household income less than $20,000). For formaldehyde and acetaldehyde, the patterns of concentration and exposure were largely reversed. Results suggest that disparities in exposure depend on pollutant type. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  10. NON-DESTRUCTIVE THERMAL BARRIER COATING SPALLATION PREDICTION BY A LOADBASED MICRO-INDENTATION TECHNIQUE

    SciTech Connect

    J. M. Tannenbaum; K. Lee; B. S.-J. Kang; M.A. Alvin

    2010-11-18

    Currently, the durability and life cycle of thermal barrier coatings (TBC) applied to gas turbine blades and combustor components are limiting the maximum temperature and subsequent efficiency at which gas turbine engines operate. The development of new materials, coating technologies and evaluation techniques is required if enhanced efficiency is to be achieved. Of the current ceramic coating materials used in gas turbine engines, yttria stabilized zirconia (YSZ) is most prevalent, its low thermal conductivity, high thermal expansion coefficient and outstanding mechanical strength make it ideal for use in TBC systems. However, residual stresses caused by coefficients of thermal expansion mismatches within the TBC system and unstable thermally grown oxides are considered the primary causes for its premature and erratic spallation failure. Through finite element simulations, it is shown that the residual stresses generated within the thermally grown oxide (TGO), bond coat (BC), YSZ and their interfaces create slight variations in indentation unloading surface stiffness response prior to spallation failure. In this research, seven air plasma sprayed and one electron beam physical vapor deposition yttria partially stabilized zirconia TBCs were subjected to isothermal and cyclic loadings at 1100°C. The associated coating degradation was evaluated using a non-destructive multiple partial unloading micro-indentation procedure. The results show that the proposed non-destructive micro-indentation evaluation technique can be an effective and specimenindependent TBC failure prediction tool capable of determining the location of initial spallation failure prior to its actual occurrence.

  11. Non-destructive forensic latent fingerprint acquisition with chromatic white light sensors

    NASA Astrophysics Data System (ADS)

    Leich, Marcus; Kiltz, Stefan; Dittmann, Jana; Vielhauer, Claus

    2011-02-01

    Non-destructive latent fingerprint acquisition is an emerging field of research, which, unlike traditional methods, makes latent fingerprints available for additional verification or further analysis like tests for substance abuse or age estimation. In this paper a series of tests is performed to investigate the overall suitability of a high resolution off-the-shelf chromatic white light sensor for the contact-less and non-destructive latent fingerprint acquisition. Our paper focuses on scanning previously determined regions with exemplary acquisition parameter settings. 3D height field and reflection data of five different latent fingerprints on six different types of surfaces (HDD platter, brushed metal, painted car body (metallic and non-metallic finish), blued metal, veneered plywood) are experimentally studied. Pre-processing is performed by removing low-frequency gradients. The quality of the results is assessed subjectively; no automated feature extraction is performed. Additionally, the degradation of the fingerprint during the acquisition period is observed. While the quality of the acquired data is highly dependent on surface structure, the sensor is capable of detecting the fingerprint on all sample surfaces. On blued metal the residual material is detected; however, the ridge line structure dissolves within minutes after fingerprint placement.

  12. Early non-destructive biofouling detection and spatial distribution: Application of oxygen sensing optodes.

    PubMed

    Farhat, N M; Staal, M; Siddiqui, A; Borisov, S M; Bucs, Sz S; Vrouwenvelder, J S

    2015-10-15

    Biofouling is a serious problem in reverse osmosis/nanofiltration (RO/NF) applications, reducing membrane performance. Early detection of biofouling plays an essential role in an adequate anti-biofouling strategy. Presently, fouling of membrane filtration systems is mainly determined by measuring changes in pressure drop, which is not exclusively linked to biofouling. Non-destructive imaging of oxygen concentrations (i) is specific for biological activity of biofilms and (ii) may enable earlier detection of biofilm accumulation than pressure drop. The objective of this study was to test whether transparent luminescent planar O2 optodes, in combination with a simple imaging system, can be used for early non-destructive biofouling detection. This biofouling detection is done by mapping the two-dimensional distribution of O2 concentrations and O2 decrease rates inside a membrane fouling simulator (MFS). Results show that at an early stage, biofouling development was detected by the oxygen sensing optodes while no significant increase in pressure drop was yet observed. Additionally, optodes could detect spatial heterogeneities in biofouling distribution at a micro scale. Biofilm development started mainly at the feed spacer crossings. The spatial and quantitative information on biological activity will lead to better understanding of the biofouling processes, contributing to the development of more effective biofouling control strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Non-destructive dielectric assessment of water permeation in composite structures

    SciTech Connect

    Boinard, P.; Boinard, E.; Pethrick, R.A.; Banks, W.M.; Crane, R.L.

    2000-07-01

    Over the last ten years, the application of high frequency dielectric spectroscopy techniques for the assessment of composite structures has been investigated. Novel approaches to assess non-destructively the evolution during ageing of adhesively bonded carbon fiber reinforced plastic (CFRP) structures and bulk glass fiber reinforced plastic (GRP) structures are presented in this paper and the results are critically assessed. The applicability and limitations of dielectric measurements, in both frequency and time domain, to the monitoring of water ingress at 30 C and 60 C are examined. The correlation between gravimetric and high frequency dielectric spectroscopy data demonstrates the suitability of the techniques regarding the assessment of water uptake in composites structures and illustrates its potential as a non-destructive evaluation (NDE) technique. The dielectric time domain response (TDR) study of adhesively bonded structures indicates a new way to assess such structures. The approach for frequency domain analysis of bulk GRP using a coaxial probe technique indicates the potential portability of the technique for in-situ measurements.

  14. A Spatially Offset Raman Spectroscopy Method for Non-Destructive Detection of Gelatin-Encapsulated Powders

    PubMed Central

    Chao, Kuanglin; Dhakal, Sagar; Qin, Jianwei; Peng, Yankun; Schmidt, Walter F.; Kim, Moon S.; Chan, Diane E.

    2017-01-01

    Non-destructive subsurface detection of encapsulated, coated, or seal-packaged foods and pharmaceuticals can help prevent distribution and consumption of counterfeit or hazardous products. This study used a Spatially Offset Raman Spectroscopy (SORS) method to detect and identify urea, ibuprofen, and acetaminophen powders contained within one or more (up to eight) layers of gelatin capsules to demonstrate subsurface chemical detection and identification. A 785-nm point-scan Raman spectroscopy system was used to acquire spatially offset Raman spectra for an offset range of 0 to 10 mm from the surfaces of 24 encapsulated samples, using a step size of 0.1 mm to obtain 101 spectral measurements per sample. As the offset distance was increased, the spectral contribution from the subsurface powder gradually outweighed that of the surface capsule layers, allowing for detection of the encapsulated powders. Containing mixed contributions from the powder and capsule, the SORS spectra for each sample were resolved into pure component spectra using self-modeling mixture analysis (SMA) and the corresponding components were identified using spectral information divergence values. As demonstrated here for detecting chemicals contained inside thick capsule layers, this SORS measurement technique coupled with SMA has the potential to be a reliable non-destructive method for subsurface inspection and authentication of foods, health supplements, and pharmaceutical products that are prepared or packaged with semi-transparent materials. PMID:28335453

  15. Non-Destructive Evaluation of Thermal Spray Coating Interface Quality by Eddy Current Method

    SciTech Connect

    B.Mi; X. Zhao; R. Bayles

    2006-05-26

    Thermal spray coating is usually applied through directing molten or softened particles at very high velocities onto a substrate. An eddy current non-destructive inspection technique is presented here for thermal spray coating interface quality characterization. Several high-velocity-oxy-fuel (HVOF) coated steel plates were produced with different surface preparation conditions before applying the coating, e.g., grit-blasted surface, wire-brush cleaned surface, and a dirty surface. A quad-frequency eddy current probe was used to manually scan over the coating surface to evaluate the bonding quality. Experimental results show that the three surface preparation conditions can be successfully differentiated by looking into the impedance difference observed from the eddy current probe. The measurement is fairly robust and consistent. More specimens are also prepared with variations of process parameters, such as spray angle, stand-off distance, and application of corrosion protective sealant, etc. They are blindly tested to evaluate the reliability of the eddy current system. Quantitative relations between the coating bond strength and the eddy current response are also established with the support of destructive testing. This non-contact, non-destructive, easy to use technique has the potential for evaluating the coating quality immediately after its application so that any defects can be corrected immediately.

  16. Rapid non-destructive assessment of pork edible quality by using VIS/NIR spectroscopic technique

    NASA Astrophysics Data System (ADS)

    Zhang, Leilei; Peng, Yankun; Dhakal, Sagar; Song, Yulin; Zhao, Juan; Zhao, Songwei

    2013-05-01

    The objectives of this research were to develop a rapid non-destructive method to evaluate the edible quality of chilled pork. A total of 42 samples were packed in seal plastic bags and stored at 4°C for 1 to 21 days. Reflectance spectra were collected from visible/near-infrared spectroscopy system in the range of 400nm to 1100nm. Microbiological, physicochemical and organoleptic characteristics such as the total viable counts (TVC), total volatile basic-nitrogen (TVB-N), pH value and color parameters L* were determined to appraise pork edible quality. Savitzky-Golay (SG) based on five and eleven smoothing points, Multiple Scattering Correlation (MSC) and first derivative pre-processing methods were employed to eliminate the spectra noise. The support vector machines (SVM) and partial least square regression (PLSR) were applied to establish prediction models using the de-noised spectra. A linear correlation was developed between the VIS/NIR spectroscopy and parameters such as TVC, TVB-N, pH and color parameter L* indexes, which could gain prediction results with Rv of 0.931, 0.844, 0.805 and 0.852, respectively. The results demonstrated that VIS/NIR spectroscopy technique combined with SVM possesses a powerful assessment capability. It can provide a potential tool for detecting pork edible quality rapidly and non-destructively.

  17. Non destructive examination of UN / U-Si fuel pellets using neutrons (preliminary assessment)

    SciTech Connect

    Bourke, Mark Andrew; Vogel, Sven C.; Voit, Stewart Lancaster; Mcclellan, Kenneth James; Losko, Adrian S.; Tremsin, Anton

    2016-03-31

    Tomographic imaging and diffraction measurements were performed on nine pellets; four UN/ U Si composite formulations (two enrichment levels), three pure U3Si5 reference formulations (two enrichment levels) and two reject pellets with visible flaws (to qualify the technique). The U-235 enrichments ranged from 0.2 to 8.8 wt.%. The nitride/silicide composites are candidate compositions for use as Accident Tolerant Fuel (ATF). The monophase U3Si5 material was included as a reference. Pellets from the same fabrication batches will be inserted in the Advanced Test Reactor at Idaho during 2016. The goal of the Advanced Non-destructive Fuel Examination work package is the development and application of non-destructive neutron imaging and scattering techniques to ceramic and metallic nuclear fuels. Data reported in this report were collected in the LANSCE run cycle that started in September 2015 and ended in March 2016. Data analysis is ongoing; thus, this report provides a preliminary review of the measurements and provides an overview of the characterized samples.

  18. Study of concrete drilling for automated non-destructive evaluation and rehabilitation system for bridge decks

    NASA Astrophysics Data System (ADS)

    Trkov, Mitja; Liu, Fei; Yi, Jingang; Baruh, Haim

    2011-04-01

    Robotic drilling is the basic process for the non-destructive rehabilitation (NDR) system in the Automated Non-destructive Evaluation and Rehabilitation System (ANDERS) for bridge decks. In this paper, we present a study and testing of a concrete drilling process that is used for robotic drilling process for bridge decks repair. We first review the ANDERS and NDR design. Then we present the experimental setup for the drilling process study. A set of testing experiments are performed considering drilling process parameters such as drill bit size, drill rotating speed, drill thrust force and types of concrete composites. Based on the experiments and analysis, we identify and find that the optimal set of drilling process parameters for the ANDERS application is 1/4-inch bit size, drill rotational speed of 1500 rpm and thrust force around 35 lbs. We also demonstrate that the monitoring of drill feeding displacement and thrust force cannot be used to detect and identify the cracks in bridge decks.

  19. Non-destructive techniques for the detection of fungal infection in cereal grains.

    PubMed

    Orina, Irene; Manley, Marena; Williams, Paul J

    2017-10-01

    Infection of cereal grains by fungi is a serious problem worldwide. Depending on the environmental conditions, cereal grains may be colonised by different species of fungi. These fungi cause reduction in yield, quality and nutritional value of the grain; and of major concern is their production of mycotoxins which are harmful to both humans and animals. Early detection of fungal contamination is an essential control measure for ensuring storage longevity and food safety. Conventional methods for detection of fungal infection, such as culture and colony techniques or immunological methods are either slow, labour intensive or difficult to automate. In recent years, there has been an increasing need to develop simple, rapid, non-destructive methods for early detection of fungal infection and mycotoxins contamination in cereal grains. Methods such as near infrared (NIR) spectroscopy, NIR hyperspectral imaging, and electronic nose were evaluated for these purposes. This paper reviews the different non-destructive techniques that have been considered thus far for detection of fungal infection and mycotoxins in cereal grains, including their principles, application and limitations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Non-destructive observation of electrically detected magnetic resonance in bulk material using AC bias.

    PubMed

    Sato, Toshiyuki; Yokoyama, Hidekatsu; Ohya, Hiroaki

    2005-07-01

    DC bias is normally found in conventional measurements of electrically detected magnetic resonance (EDMR). Usually, electrodes are formed on the sample surface to make ohmic contacts for detecting changes in the electrical characteristics of the sample material. Thus, destructive procedures are required to detect the EDMR signal of bulk material with such methods. An AC bias detection technique was developed to allow the non-destructive EDMR measurement of bulk materials. An AC bridge circuit was constructed to detect the change in impedance of the sample, which when changed by ESR, an unbalanced AC voltage can be detected. By detecting this AC bias, it is possible to cancel the effects, such as Shottky barriers, that disturb the ohmic contact between the electrodes and a sample material. Further, the AC bias current penetrates the thin surface layer of a sample such as silicon oxide, which normally obstructs a DC current. This method was utilized using conductive rubber contacts for non-destructive EDMR measurements of part of a silicon wafer. EDMR spectra observed were the same as those obtained by the conventional method of using DC bias detection.

  1. Non-destructive observation of electrically detected magnetic resonance in bulk material using AC bias

    NASA Astrophysics Data System (ADS)

    Sato, Toshiyuki; Yokoyama, Hidekatsu; Ohya, Hiroaki

    2005-07-01

    DC bias is normally found in conventional measurements of electrically detected magnetic resonance (EDMR). Usually, electrodes are formed on the sample surface to make ohmic contacts for detecting changes in the electrical characteristics of the sample material. Thus, destructive procedures are required to detect the EDMR signal of bulk material with such methods. An AC bias detection technique was developed to allow the non-destructive EDMR measurement of bulk materials. An AC bridge circuit was constructed to detect the change in impedance of the sample, which when changed by ESR, an unbalanced AC voltage can be detected. By detecting this AC bias, it is possible to cancel the effects, such as Shottky barriers, that disturb the ohmic contact between the electrodes and a sample material. Further, the AC bias current penetrates the thin surface layer of a sample such as silicon oxide, which normally obstructs a DC current. This method was utilized using conductive rubber contacts for non-destructive EDMR measurements of part of a silicon wafer. EDMR spectra observed were the same as those obtained by the conventional method of using DC bias detection.

  2. Non-destructive Magnetic Evaluation of Laser Weld Quality in Hot Rolled Coils

    NASA Astrophysics Data System (ADS)

    Mohapatra, J. N.; Chakradhar, I.; Rao, K. R. C.; Rao, V. V. L.; Kaza, Marutiram

    2015-06-01

    Weld quality evaluation was conducted on laser welded thin sectsions (2 mm) of hot-rolled (HR) low-carbon steel coils during cold rolling process. The analysis revealed that the poor welds consisting of the weld defects like incomplete fusion, cluster of porosity, and large difference in hardness between the weld zone and base metal were responsible for the weld failures. Experiments were conducted by varying the welding parameters; laser power and welding speed to optimize the parameters for minimizing the weld defects. The optimized weld process parameters have helped elimination of weld defects and the results are verified with microscopy and microhardness measurements. As destructive evaluation techniques are time consuming and not always permitted in industrial applications, attempts have been made in the present investigation for the utilization of suitable non-destructive techniques for the evaluation of weld quality. Non-destructive magnetic techniques of magnetic hysteresis loop and magnetic Barkhausen emissions were used in the present investigation to establish possible correlations of magnetic properties across the weld seam with the mechanical property (microhardness) for evaluation of weld quality. It is inferred that the magnetic properties of coercivity and inverse of root mean square voltage can be effectively utilized to determine weld quality in HR steel coils.

  3. Non-destructive Testing of Forged Metallic Materials by Active Infrared Thermography

    NASA Astrophysics Data System (ADS)

    Maillard, S.; Cadith, J.; Bouteille, P.; Legros, G.; Bodnar, J. L.; Detalle, V.

    2012-11-01

    Nowadays, infrared thermography is considered as the reference method in many applications such as safety, the inspection of electric installations, or the inspection of buildings' heat insulation. In recent years, the evolution of both material and data-processing tools also allows the development of thermography as a real non-destructive testing method. Thus, by subjecting the element to be inspected to an external excitation and by analyzing the propagation of heat in the examined zone, it is possible to highlight surface or subsurface defects such as cracks, delaminations, or corrosion. One speaks then about active infrared thermography. In this study, some results obtained during the collective studies carried out by CETIM and the University of Reims for the forging industry are presented. Various experimental possibilities offered by active thermography are presented and the interest in this method in comparison with the traditional non-destructive testing methods (penetrant testing and magnetic particle inspection) is discussed. For example, comparative results on a forged cracked hub, a steering joint, and a threaded rod are presented. They highlight the interest of infrared thermography stimulated by induction for forged parts.

  4. Non-destructive analysis for the investigation of decomposition phenomena of historical manuscripts and prints

    NASA Astrophysics Data System (ADS)

    Faubel, Werner; Staub, Susanne; Simon, Rolf; Heissler, Stefan; Pataki, Andrea; Banik, Gerhard

    2007-07-01

    As a contribution to the increasing efforts to preserve cultural heritage, historical books as well as illuminated manuscripts endangered by corrosive writing and printing materials or destructive coloring matters, non-destructive analytical methods are highly desirable enabling an in-situ examination of the surface status of an object. The development and application of a novel combination of non-destructive analytic methods based on (a) synchrotron radiation induced micro-X-ray fluorescence (SR-μXRF) and (b) Fourier transform infrared (FTIR) microscope allows to investigate the state as well as the effectiveness of conservation procedures for historical manuscripts. Examples of measurements include (1) an iron gall ink manuscript of a historical memo on legal land description of the year 1769, (2) an original hand colored herbal of the years 1536/38 from the Senckenbergische Bibliothek, Frankfurt, and (3) the incunabula Johannes von Saaz: "Der Ackermann aus Boehmen" fated from 1463 and printed by Albrecht Pfister, Bamberg, owned by the Herzog August Bibliothek, Wolfenbuettel.

  5. Non-destructive 3D shape measurement of transparent and black objects with thermal fringes

    NASA Astrophysics Data System (ADS)

    Brahm, Anika; Rößler, Conrad; Dietrich, Patrick; Heist, Stefan; Kühmstedt, Peter; Notni, Gunther

    2016-05-01

    Fringe projection is a well-established optical method for the non-destructive contactless three-dimensional (3D) measurement of object surfaces. Typically, fringe sequences in the visible wavelength range (VIS) are projected onto the surfaces of objects to be measured and are observed by two cameras in a stereo vision setup. The reconstruction is done by finding corresponding pixels in both cameras followed by triangulation. Problems can occur if the properties of some materials disturb the measurements. If the objects are transparent, translucent, reflective, or strongly absorbing in the VIS range, the projected patterns cannot be recorded properly. To overcome these challenges, we present a new alternative approach in the infrared (IR) region of the electromagnetic spectrum. For this purpose, two long-wavelength infrared (LWIR) cameras (7.5 - 13 μm) are used to detect the emitted heat radiation from surfaces which is induced by a pattern projection unit driven by a CO2 laser (10.6 μm). Thus, materials like glass or black objects, e.g. carbon fiber materials, can be measured non-destructively without the need of any additional paintings. We will demonstrate the basic principles of this heat pattern approach and show two types of 3D systems based on a freeform mirror and a GOBO wheel (GOes Before Optics) projector unit.

  6. Design of an electron-accelerator-driven compact neutron source for non-destructive assay

    NASA Astrophysics Data System (ADS)

    Murata, A.; Ikeda, S.; Hayashizaki, N.

    2017-09-01

    The threat of nuclear and radiological terrorism remains one of the greatest challenges to international security, and the threat is constantly evolving. In order to prevent nuclear terrorism, it is important to avoid unlawful import of nuclear materials, such as uranium and plutonium. Development of technologies for non-destructive measurement, detection and recognition of nuclear materials is essential for control at national borders. At Tokyo Institute of Technology, a compact neutron source system driven by an electron-accelerator has been designed for non-destructive assay (NDA). This system is composed of a combination of an S-band (2.856 GHz) RF-gun, a tungsten target to produce photons by bremsstrahlung, a beryllium target, which is suitable for use in generating neutrons because of the low threshold energy of photonuclear reactions, and a moderator to thermalize the fast neutrons. The advantage of this system can accelerate a short pulse beam with a pulse width less than 1 μs which is difficult to produce by neutron generators. The amounts of photons and neutron produced by electron beams were simulated using the Monte Carlo simulation code PHITS 2.82. When the RF-gun is operated with an average electron beam current of 0.1 mA, it is expected that the neutron intensities are 1.19 × 109 n/s and 9.94 × 109 n/s for incident electron beam energies of 5 MeV and 10 MeV, respectively.

  7. A Distributive, Non-Destructive, Real-Time Approach to Snowpack Monitoring

    NASA Technical Reports Server (NTRS)

    Frolik, Jeff; Skalka, Christian

    2012-01-01

    This invention is designed to ascertain the snow water equivalence (SWE) of snowpacks with better spatial and temporal resolutions than present techniques. The approach is ground-based, as opposed to some techniques that are air-based. In addition, the approach is compact, non-destructive, and can be communicated with remotely, and thus can be deployed in areas not possible with current methods. Presently there are two principal ground-based techniques for obtaining SWE measurements. The first is manual snow core measurements of the snowpack. This approach is labor-intensive, destructive, and has poor temporal resolution. The second approach is to deploy a large (e.g., 3x3 m) snowpillow, which requires significant infrastructure, is potentially hazardous [uses a approximately equal to 200-gallon (approximately equal to 760-L) antifreeze-filled bladder], and requires deployment in a large, flat area. High deployment costs necessitate few installations, thus yielding poor spatial resolution of data. Both approaches have limited usefulness in complex and/or avalanche-prone terrains. This approach is compact, non-destructive to the snowpack, provides high temporal resolution data, and due to potential low cost, can be deployed with high spatial resolution. The invention consists of three primary components: a robust wireless network and computing platform designed for harsh climates, new SWE sensing strategies, and algorithms for smart sampling, data logging, and SWE computation.

  8. Non-Destructive Observations of Internal Micro-Defects Using Scanning Electron-Induced Acoustic Microscope

    NASA Astrophysics Data System (ADS)

    Koyama, Atsuhiro; Shibutani, Yoji

    Scanning electron-induced acoustic microscope (SEAM) has been developed as a new tool for non-destructive observations of the internal microstructures of materials. It consists of the electric chopper to pulse the high current electron beam and the detector of the longitudinal acoustic waves, both being attached to the commercial scanning electron microscope (SEM). The cyclic chopping of electron beam with extremely high frequency of a few hundred kilohertz makes the thermal wave due to the cyclic temperature rise with the short period. The wavelength of thermal wave may determine the essential SEAM resolution, because it's much smaller than the thermal stress wave (that is, the acoustic wave), which has just the role of conveying the information of thermal wave disturbance due to unexpected change as defects. Our own-built SEAM gives the best performance for observing the internal defects like the micro-voids, because it susceptibly senses the local difference of thermal properties in the sample. The paper indicates that some non-destructive observations for the micro-voids with a few microns order existing in the sintered materials are exhibited in conjunction with their destructive observations using focused-ion beam (FIB) technique to make certain of those as the proof.

  9. Are those bugs reflective? Non-destructive biofilm imaging with white light interferometry

    SciTech Connect

    Larimer, Curtis J.; Brann, Michelle R.; Suter, Jonathan D.; Bonheyo, George T.; Addleman, Raymond S.

    2016-08-28

    White light interferometry (WLI) is not typically used to image bacterial biofilms that are immersed in water because there is insufficient refractive index contrast to induce reflection from the biofilm’s interface. The soft structure and water-like bulk properties of hydrated biofilms make them difficult to characterize in situ by any means, especially in a non-destructive manner. Here we describe a new method for measuring and monitoring the thickness and topology of live biofilms using a WLI microscope. A microfluidic system was used to create a reflective interface on the surface of biofilms. Live biofilm samples were monitored non-destructively over time. The method enables surface metrology measurements (roughness, surface area) and a novel approach to measuring thickness of the thin hydrated biofilms. Increase in surface roughness preceded observable increase in biofilm thickness, indicating that this measure may be used to predict future development of biofilms. We have also developed a flow cell that enables WLI biofilm imaging in a dynamic environment. We have used this flow cell to observe changes in biofilm structure in response to changes in environmental conditions - flow velocity, availability of nutrients, and presence of biocides.

  10. Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines

    PubMed Central

    Busschots, Steven; O’Toole, Sharon; O’Leary, John J.; Stordal, Britta

    2014-01-01

    Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. • Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner. • The technique is quick, affordable and eliminates sample manipulation. • The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines. PMID:26150966

  11. Non-destructive staging of barley reproductive development for molecular analysis based upon external morphology.

    PubMed

    Gómez, José Fernández; Wilson, Zoe A

    2012-06-01

    A prerequisite to study the molecular genetic pathways of pollen and anther development is an accurate staging system for reproductive development. However in barley, floret formation occurs mainly within the pseudostem, which makes the observation of floret development and access to the floret particularly difficult without dissecting the plant. Thus selecting stages for molecular analysis cannot be done non-destructively. A staging method has therefore been developed for barley in order to define the relationship between readily detectable growth points and reproductive development, to provide a clear key to enable accurate selection of reproductive material. Initial staging followed the traditional Zadoks decimal system, with minor adaptations to stages 31-34 and stage 37. The later stages, from 37 onward, were replaced by growth staging based upon the last flag elongation (LFE) and the position occupied by the spike within the pseudostem. Spike size could be readily predicted by using the staging system incorporating Zadoks stages 31-37, supplemented with substages and by LFE staging to improve accuracy. The different spike sizes, as well as the LFE stages, showed a clear relationship to events occurring within the anther, as confirmed by light microscopy of the anthers. The defined relationship between spike size and development to anther development now makes possible the accurate prediction of anther and pollen progression by external staging. This, therefore, provides a mechanism for non-destructive selection of material for analysis that is critical for the molecular characterization of genes in anther and pollen development.

  12. Non-destructive measurement of soil liquefaction density change by crosshole radar tomography, Treasure Island, California

    USGS Publications Warehouse

    Kayen, Robert E.; Barnhardt, Walter A.; Ashford, Scott; Rollins, Kyle

    2000-01-01

    A ground penetrating radar (GPR) experiment at the Treasure Island Test Site [TILT] was performed to non-destructively image the soil column for changes in density prior to, and following, a liquefaction event. The intervening liquefaction was achieved by controlled blasting. A geotechnical borehole radar technique was used to acquire high-resolution 2-D radar velocity data. This method of non-destructive site characterization uses radar trans-illumination surveys through the soil column and tomographic data manipulation techniques to construct radar velocity tomograms, from which averaged void ratios can be derived at 0.25 - 0.5m pixel footprints. Tomograms of void ratio were constructed through the relation between soil porosity and dielectric constant. Both pre- and post-blast tomograms were collected and indicate that liquefaction related densification occurred at the site. Volumetric strains estimated from the tomograms correlate well with the observed settlement at the site. The 2-D imagery of void ratio can serve as high-resolution data layers for numerical site response analysis.

  13. Neural network and principal component regression in non-destructive soluble solids content assessment: a comparison.

    PubMed

    Chia, Kim-seng; Abdul Rahim, Herlina; Abdul Rahim, Ruzairi

    2012-02-01

    Visible and near infrared spectroscopy is a non-destructive, green, and rapid technology that can be utilized to estimate the components of interest without conditioning it, as compared with classical analytical methods. The objective of this paper is to compare the performance of artificial neural network (ANN) (a nonlinear model) and principal component regression (PCR) (a linear model) based on visible and shortwave near infrared (VIS-SWNIR) (400-1000 nm) spectra in the non-destructive soluble solids content measurement of an apple. First, we used multiplicative scattering correction to pre-process the spectral data. Second, PCR was applied to estimate the optimal number of input variables. Third, the input variables with an optimal amount were used as the inputs of both multiple linear regression and ANN models. The initial weights and the number of hidden neurons were adjusted to optimize the performance of ANN. Findings suggest that the predictive performance of ANN with two hidden neurons outperforms that of PCR.

  14. Processes for non-destructive transfer of graphene: widening the bottleneck for industrial scale production

    NASA Astrophysics Data System (ADS)

    Zaretski, Aliaksandr V.; Lipomi, Darren J.

    2015-05-01

    The exceptional charge-transport, mechanical, and barrier properties of graphene are well known. High-quality films of single-layer graphene produced over large areas, however, are extremely expensive. The high cost of graphene precludes its use in industries--such as transparent electrodes and flexible packaging--that might take full advantage of its properties. This minireview presents several strategies for the transfer of graphene from the substrates used for growth to substrates used for the final application. Each strategy shares the characteristic of being non-destructive: that is, the growth substrate remains reusable for further synthesis of new graphene. These processes have the potential to lower significantly the costs of manufacturing graphene, to increase production yields, and to minimize environmental impact. This article is divided into sections on (i) the synthesis of high-quality single-layer graphene and (ii) its non-destructive transfer to a host substrate. Section (ii) is further divided according to the substrate from which graphene is transferred: single-crystalline wafers or flexible copper foils. We also comment, wherever possible, on defects produced as a result of the transfer, and potential strategies to mitigate these defects. We conclude that several methods for the green synthesis and transfer of graphene have several of the right characteristics to be useful in industrial scale production.

  15. Non-destructive on-chip cell sorting system with real-time microscopic image processing.

    PubMed

    Takahashi, Kazunori; Hattori, Akihiro; Suzuki, Ikurou; Ichiki, Takanori; Yasuda, Kenji

    2004-06-03

    Studying cell functions for cellomics studies often requires the use of purified individual cells from mixtures of various kinds of cells. We have developed a new non-destructive on-chip cell sorting system for single cell based cultivation, by exploiting the advantage of microfluidics and electrostatic force. The system consists of the following two parts: a cell sorting chip made of poly-dimethylsiloxane (PDMS) on a 0.2-mm-thick glass slide, and an image analysis system with a phase-contrast/fluorescence microscope. The unique features of our system include (i) identification of a target from sample cells is achieved by comparison of the 0.2-microm-resolution phase-contrast and fluorescence images of cells in the microchannel every 1/30 s; (ii) non-destructive sorting of target cells in a laminar flow by application of electrostatic repulsion force for removing unrequited cells from the one laminar flow to the other; (iii) the use of agar gel for electrodes in order to minimize the effect on cells by electrochemical reactions of electrodes, and (iv) pre-filter, which was fabricated within the channel for removal of dust contained in a sample solution from tissue extracts. The sorting chip is capable of continuous operation and we have purified more than ten thousand cells for cultivation without damaging them. Our design has proved to be very efficient and suitable for the routine use in cell purification experiments.

  16. Compressive strength evaluation of structural lightweight concrete by non-destructive ultrasonic pulse velocity method.

    PubMed

    Bogas, J Alexandre; Gomes, M Glória; Gomes, Augusto

    2013-07-01

    In this paper the compressive strength of a wide range of structural lightweight aggregate concrete mixes is evaluated by the non-destructive ultrasonic pulse velocity method. This study involves about 84 different compositions tested between 3 and 180 days for compressive strengths ranging from about 30 to 80 MPa. The influence of several factors on the relation between the ultrasonic pulse velocity and compressive strength is examined. These factors include the cement type and content, amount of water, type of admixture, initial wetting conditions, type and volume of aggregate and the partial replacement of normal weight coarse and fine aggregates by lightweight aggregates. It is found that lightweight and normal weight concretes are affected differently by mix design parameters. In addition, the prediction of the concrete's compressive strength by means of the non-destructive ultrasonic pulse velocity test is studied. Based on the dependence of the ultrasonic pulse velocity on the density and elasticity of concrete, a simplified expression is proposed to estimate the compressive strength, regardless the type of concrete and its composition. More than 200 results for different types of aggregates and concrete compositions were analyzed and high correlation coefficients were obtained. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Variation in gymnemic acid content and non-destructive harvesting of Gymnema sylvestre (Gudmar).

    PubMed

    Pandey, Ashok Kumar; Yadav, Swati

    2010-09-01

    Madhunashini (Gymnema sylvestre R. Br.) commonly known as 'Gudmar' in Hindi is an important medicinal climber and extensively used in almost all Indian System of Medicine as a remedy for diabetes, rheumatism, cough, ulcer, jaundice, dyspepsia, constipation, eyes pain and also in snakebite. In India, it is found growing in Andhra Pradesh, Bihar, Chhattisgarh, Karnataka, Kerala, Madhya Pradesh, Maharastra, Orissa, Tamil Nadu, Uttar Pradesh and West Bengal. The major phytoconstituents are gymnemic acids, gudmarin and saponins. In the present study, Gymnema germplasm collected from various regions of Madhya Pradesh was evaluated on the basis of their morphological characteristics and gymnemic acid content. Gymnemic acid content in the leaves was estimated by HPLC. We have also standardized the non-destructive harvesting practices of Gudmar. Selective harvesting was done without harming the main plant. Only mature leaves (60%) were hand plucked in the month of October. Second harvest was done in the month of June. Data revealed that gymnemic acid content varied between 0.96% ± 0.03 (Seoni) to 1.58% ±0.03 (Amarkantak). It was also observed that the leaves left at the time of 1(st) harvest during October matured in June at the time of 2(nd) harvest. Non destructive harvesting practice did not have any negative impact on overall development of the plant. It is evident that there is wide variation in the morphological characteristics and gymnemic acid content in G. sylvestre collected from various locations, which can be exploited for further crop improvement programmes.

  18. Non-destructive Detection for Mold Colonies in Rice Based on Hyperspectra and GWO-SVR.

    PubMed

    Sunli, Cong; Jun, Sun; Hanping, Mao; Xiaohong, Wu; Pei, Wang; Xiaodong, Zhang

    2017-08-08

    Mold contamination of grains not only contributes to unedible food, resulting in economic losses, but also leads to mold in humans and livestock, even can be carcinogenic to them. Rice as one of the main grain varieties, if improper storage, is easily to mildew. In order to detect the total number of mold colonies in rice more accurately, a method based on hyperspectral imaging technology was investigated. In this paper, non-destructive detection for the total number of mold colonies in rice was performed from the angle of spectral analysis. The determination coefficient of 0.9621 for calibration set and 0.9511 for prediction set between the spectral data and number of mold colonies were eventually achieved by establishing the best support vector regression (SVR) model, optimised by gray wolf optimization (GWO) algorithm. The hyperspectral imaging technology combined with the optimal model (GWO-SVR) is feasible for non-destructive detection of the total number of mold colonies in rice, and so hopefully to provide a promising tool for the mold detection of other agricultural products. This article is protected by copyright. All rights reserved.

  19. Non-destructive inspection in industrial equipment using robotic mobile manipulation

    NASA Astrophysics Data System (ADS)

    Maurtua, Iñaki; Susperregi, Loreto; Ansuategui, Ander; Fernández, Ane; Ibarguren, Aitor; Molina, Jorge; Tubio, Carlos; Villasante, Cristobal; Felsch, Torsten; Pérez, Carmen; Rodriguez, Jorge R.; Ghrissi, Meftah

    2016-05-01

    MAINBOT project has developed service robots based applications to autonomously execute inspection tasks in extensive industrial plants in equipment that is arranged horizontally (using ground robots) or vertically (climbing robots). The industrial objective has been to provide a means to help measuring several physical parameters in multiple points by autonomous robots, able to navigate and climb structures, handling non-destructive testing sensors. MAINBOT has validated the solutions in two solar thermal plants (cylindrical-parabolic collectors and central tower), that are very demanding from mobile manipulation point of view mainly due to the extension (e.g. a thermal solar plant of 50Mw, with 400 hectares, 400.000 mirrors, 180 km of absorber tubes, 140m height tower), the variability of conditions (outdoor, day-night), safety requirements, etc. Once the technology was validated in simulation, the system was deployed in real setups and different validation tests carried out. In this paper two of the achievements related with the ground mobile inspection system are presented: (1) Autonomous navigation localization and planning algorithms to manage navigation in huge extensions and (2) Non-Destructive Inspection operations: thermography based detection algorithms to provide automatic inspection abilities to the robots.

  20. Non-destructive sampling of rock-dwelling microbial communities using sterile adhesive tape.

    PubMed

    Cutler, Nick A; Oliver, Anna E; Viles, Heather A; Whiteley, Andrew S

    2012-12-01

    Building stone provides a habitat for an array of microorganisms, many of which have been demonstrated to have a deleterious effect on the appearance and/or structural integrity of stone masonry. It is essential to understand the composition and structure of stone-dwelling (lithobiontic) microbial communities if successful stone conservation strategies are to be applied, particularly in the face of global environmental change. Ideally, the techniques used to sample such assemblages should be non-destructive due to the sensitive conservation status of many stone buildings. This paper quantitatively assesses the performance of sterile adhesive tape as a non-destructive sampling technique and compares the results of tape sampling with an alternative, destructive, sampling method. We used DNA fingerprinting (TRFLP) to characterise the algal, fungal and bacterial communities living on a stone slab. Our results demonstrate that tape sampling may be used to collect viable quantities of microbial DNA from environmental samples. This technique is ideally suited to the sampling of microbial biofilms, particularly when these communities are dominated by green algae. It provides a good approximation of total community diversity (i.e. the aggregate diversity of epilithic and endolithic communities). Tape sampling is straightforward, rapid and cost effective. When combined with molecular analytical techniques, this sampling method has the potential to make a major contribution to efforts to understand the structure of lithobiontic microbial communities and our ability to predict the response of such communities to future environmental change.

  1. Non-destructive high-throughput DNA extraction and genotyping methods for cotton seeds and seedlings.

    PubMed

    Zheng, Xiuting; Hoegenauer, Kevin A; Maeda, Andrea B V; Wang, Fei; Stelly, David M; Nichols, Robert L; Jones, Don C

    2015-05-01

    Extensive use of targeted PCR-based genotyping is precluded for many plant research laboratories by the cost and time required for DNA extraction. Using cotton (Gossypium hirsutum) as a model for plants with medium-sized seeds, we report here manual procedures for inexpensive non-destructive high-throughput extraction of DNA suitable for PCR-based genotyping of large numbers of individual seeds and seedlings. By sampling only small amounts of cotyledon tissue of ungerminated seed or young seedlings, damage is minimized, and viability is not discernibly affected. The yield of DNA from each seed or seedling is typically sufficient for 1000 or 500 PCR reactions, respectively. For seeds, the tissue sampling procedure relies on a modified 96-well plate that is used subsequently for seed storage. For seeds and seedlings, the DNA is extracted in a strongly basic DNA buffer that is later neutralized and diluted. Extracts can be used directly for high-throughput PCR-based genotyping. Any laboratory can thus extract DNA from thousands of individual seeds/seedlings per person-day at a very modest cost for consumables (~$0.05 per sample). Being non-destructive, our approach enables a wide variety of time- and resource-saving applications, such as marker-assisted selection (MAS), before planting, transplanting, and flowering.

  2. Non-destructive detection of pesticide residues in cucumber using visible/near-infrared spectroscopy.

    PubMed

    Jamshidi, Bahareh; Mohajerani, Ezeddin; Jamshidi, Jamshid; Minaei, Saeid; Sharifi, Ahmad

    2015-01-01

    The feasibility of using visible/near-infrared (Vis/NIR) spectroscopy was assessed for non-destructive detection of diazinon residues in intact cucumbers. Vis/NIR spectra of diazinon solution and cucumber samples without and with different concentrations of diazinon residue were analysed at the range of 450-1000 nm. Partial least squares-discriminant analysis (PLS-DA) models were developed based on different spectral pre-processing techniques to classify cucumbers with contents of diazinon below and above the MRL as safe and unsafe samples, respectively. The best model was obtained using a first-derivative method with the lowest standard error of cross-validation (SECV = 0.366). Moreover, total percentages of correctly classified samples in calibration and prediction sets were 97.5% and 92.31%, respectively. It was concluded that Vis/NIR spectroscopy could be an appropriate, fast and non-destructive technology for safety control of intact cucumbers by the absence/presence of diazinon residues.

  3. Non-invasive and non-destructive measurements of confluence in cultured adherent cell lines.

    PubMed

    Busschots, Steven; O'Toole, Sharon; O'Leary, John J; Stordal, Britta

    2015-01-01

    Many protocols used for measuring the growth of adherent monolayer cells in vitro are invasive, destructive and do not allow for the continued, undisturbed growth of cells within flasks. Protocols often use indirect methods for measuring proliferation. Microscopy techniques can analyse cell proliferation in a non-invasive or non-destructive manner but often use expensive equipment and software algorithms. In this method images of cells within flasks are captured by photographing under a standard inverted phase contract light microscope using a digital camera with a camera lens adaptor. Images are analysed for confluence using ImageJ freeware resulting in a measure of confluence known as an Area Fraction (AF) output. An example of the AF method in use on OVCAR8 and UPN251 cell lines is included. •Measurements of confluence from growing adherent cell lines in cell culture flasks is obtained in a non-invasive, non-destructive, label-free manner.•The technique is quick, affordable and eliminates sample manipulation.•The technique provides an objective, consistent measure of when cells reach confluence and is highly correlated to manual counting with a haemocytometer. The average correlation co-efficient from a Spearman correlation (n = 3) was 0.99 ± 0.008 for OVCAR8 (p = 0.01) and 0.99 ± 0.01 for UPN251 (p = 0.01) cell lines.

  4. Processes for non-destructive transfer of graphene: widening the bottleneck for industrial scale production.

    PubMed

    Zaretski, Aliaksandr V; Lipomi, Darren J

    2015-06-14

    The exceptional charge-transport, mechanical, and barrier properties of graphene are well known. High-quality films of single-layer graphene produced over large areas, however, are extremely expensive. The high cost of graphene precludes its use in industries-such as transparent electrodes and flexible packaging-that might take full advantage of its properties. This minireview presents several strategies for the transfer of graphene from the substrates used for growth to substrates used for the final application. Each strategy shares the characteristic of being non-destructive: that is, the growth substrate remains reusable for further synthesis of new graphene. These processes have the potential to lower significantly the costs of manufacturing graphene, to increase production yields, and to minimize environmental impact. This article is divided into sections on (i) the synthesis of high-quality single-layer graphene and (ii) its non-destructive transfer to a host substrate. Section (ii) is further divided according to the substrate from which graphene is transferred: single-crystalline wafers or flexible copper foils. We also comment, wherever possible, on defects produced as a result of the transfer, and potential strategies to mitigate these defects. We conclude that several methods for the green synthesis and transfer of graphene have several of the right characteristics to be useful in industrial scale production.

  5. A Spatially Offset Raman Spectroscopy Method for Non-Destructive Detection of Gelatin-Encapsulated Powders.

    PubMed

    Chao, Kuanglin; Dhakal, Sagar; Qin, Jianwei; Peng, Yankun; Schmidt, Walter F; Kim, Moon S; Chan, Diane E

    2017-03-18

    Non-destructive subsurface detection of encapsulated, coated, or seal-packaged foods and pharmaceuticals can help prevent distribution and consumption of counterfeit or hazardous products. This study used a Spatially Offset Raman Spectroscopy (SORS) method to detect and identify urea, ibuprofen, and acetaminophen powders contained within one or more (up to eight) layers of gelatin capsules to demonstrate subsurface chemical detection and identification. A 785-nm point-scan Raman spectroscopy system was used to acquire spatially offset Raman spectra for an offset range of 0 to 10 mm from the surfaces of 24 encapsulated samples, using a step size of 0.1 mm to obtain 101 spectral measurements per sample. As the offset distance was increased, the spectral contribution from the subsurface powder gradually outweighed that of the surface capsule layers, allowing for detection of the encapsulated powders. Containing mixed contributions from the powder and capsule, the SORS spectra for each sample were resolved into pure component spectra using self-modeling mixture analysis (SMA) and the corresponding components were identified using spectral information divergence values. As demonstrated here for detecting chemicals contained inside thick capsule layers, this SORS measurement technique coupled with SMA has the potential to be a reliable non-destructive method for subsurface inspection and authentication of foods, health supplements, and pharmaceutical products that are prepared or packaged with semi-transparent materials.

  6. Non-destructive investigation of a time capsule using neutron radiography and X-ray fluorescence

    NASA Astrophysics Data System (ADS)

    MacDonald, B. L.; Vanderstelt, J.; O'Meara, J.; McNeill, F. E.

    2016-01-01

    Non-destructive analytical techniques are becoming increasingly important for the study of objects of cultural heritage interest. This study applied two techniques: X-ray fluorescence and neutron radiography, for the investigation of a capped, tubular metal object recovered from an urban construction site in Gore Park, Hamilton, Canada. The site is an urban park containing a World War I commemorative monument that underwent renovation and relocation. Historical documentation suggested that the object buried underneath the monument was a time capsule containing a paper document listing the names of 1800 Canadians who died during WWI. The purpose of this study was to assess the condition of the object, and to verify if it was what the historical records purported. XRF analysis was used to characterize the elemental composition of the metal artifact, while neutron radiography revealed that its contents were congruent with historical records and remained intact after being interred for 91 years. Results of this study demonstrate the value of non-destructive techniques for the analysis and preservation of cultural heritage.

  7. Are those bugs reflective? non-destructive biofilm imaging with white light interferometry

    NASA Astrophysics Data System (ADS)

    Larimer, Curtis; Brann, Michelle; Suter, Jonathan D.; Bonheyo, George; Addleman, R. Shane

    2016-08-01

    White light interferometry (WLI) is not typically used to image bacterial biofilms that are immersed in water because there is insufficient refractive index contrast to induce reflection from the biofilm's interface. The soft structure and water-like bulk properties of hydrated biofilms make them difficult to characterize in situ by any means, especially in a non-destructive manner. Here we describe a new method for measuring and monitoring the thickness and topology of live biofilms using a WLI microscope. A microfluidic system was used to create a reflective interface on the surface of biofilms. Live biofilm samples were monitored non-destructively over time. The method enables surface metrology measurements (roughness, surface area) and a novel approach to measuring thickness of the thin hydrated biofilms. Increase in surface roughness preceded observable increase in biofilm thickness, indicating that this measure may be used to predict future development of biofilms. We have also developed a flow cell that enables WLI biofilm imaging in a dynamic environment. We have used this flow cell to observe changes in biofilm structure in response to changes in environmental conditions - flow velocity, availability of nutrients, and presence of biocides.

  8. Neural network and principal component regression in non-destructive soluble solids content assessment: a comparison*

    PubMed Central

    Chia, Kim-seng; Abdul Rahim, Herlina; Abdul Rahim, Ruzairi

    2012-01-01

    Visible and near infrared spectroscopy is a non-destructive, green, and rapid technology that can be utilized to estimate the components of interest without conditioning it, as compared with classical analytical methods. The objective of this paper is to compare the performance of artificial neural network (ANN) (a nonlinear model) and principal component regression (PCR) (a linear model) based on visible and shortwave near infrared (VIS-SWNIR) (400–1000 nm) spectra in the non-destructive soluble solids content measurement of an apple. First, we used multiplicative scattering correction to pre-process the spectral data. Second, PCR was applied to estimate the optimal number of input variables. Third, the input variables with an optimal amount were used as the inputs of both multiple linear regression and ANN models. The initial weights and the number of hidden neurons were adjusted to optimize the performance of ANN. Findings suggest that the predictive performance of ANN with two hidden neurons outperforms that of PCR. PMID:22302428

  9. Non-Destructive Thermography Analysis of Impact Damage on Large-Scale CFRP Automotive Parts

    PubMed Central

    Maier, Alexander; Schmidt, Roland; Oswald-Tranta, Beate; Schledjewski, Ralf

    2014-01-01

    Laminated composites are increasingly used in aeronautics and the wind energy industry, as well as in the automotive industry. In these applications, the construction and processing need to fulfill the highest requirements regarding weight and mechanical properties. Environmental issues, like fuel consumption and CO2-footprint, set new challenges in producing lightweight parts that meet the highly monitored standards for these branches. In the automotive industry, one main aspect of construction is the impact behavior of structural parts. To verify the quality of parts made from composite materials with little effort, cost and time, non-destructive test methods are increasingly used. A highly recommended non-destructive testing method is thermography analysis. In this work, a prototype for a car’s base plate was produced by using vacuum infusion. For research work, testing specimens were produced with the same multi-layer build up as the prototypes. These specimens were charged with defined loads in impact tests to simulate the effect of stone chips. Afterwards, the impacted specimens were investigated with thermography analysis. The research results in that work will help to understand the possible fields of application and the usage of thermography analysis as the first quick and economic failure detection method for automotive parts. PMID:28788464

  10. Non-Destructive Thermography Analysis of Impact Damage on Large-Scale CFRP Automotive Parts.

    PubMed

    Maier, Alexander; Schmidt, Roland; Oswald-Tranta, Beate; Schledjewski, Ralf

    2014-01-14

    Laminated composites are increasingly used in aeronautics and the wind energy industry, as well as in the automotive industry. In these applications, the construction and processing need to fulfill the highest requirements regarding weight and mechanical properties. Environmental issues, like fuel consumption and CO₂-footprint, set new challenges in producing lightweight parts that meet the highly monitored standards for these branches. In the automotive industry, one main aspect of construction is the impact behavior of structural parts. To verify the quality of parts made from composite materials with little effort, cost and time, non-destructive test methods are increasingly used. A highly recommended non-destructive testing method is thermography analysis. In this work, a prototype for a car's base plate was produced by using vacuum infusion. For research work, testing specimens were produced with the same multi-layer build up as the prototypes. These specimens were charged with defined loads in impact tests to simulate the effect of stone chips. Afterwards, the impacted specimens were investigated with thermography analysis. The research results in that work will help to understand the possible fields of application and the usage of thermography analysis as the first quick and economic failure detection method for automotive parts.

  11. Non-Destructive Evaluation of Grain Structure Using Air-Coupled Ultrasonics

    SciTech Connect

    Belvin, A. D.; Burrell, R. K.; Cole, E.G.

    2009-08-01

    Cast material has a grain structure that is relatively non-uniform. There is a desire to evaluate the grain structure of this material non-destructively. Traditionally, grain size measurement is a destructive process involving the sectioning and metallographic imaging of the material. Generally, this is performed on a representative sample on a periodic basis. Sampling is inefficient and costly. Furthermore, the resulting data may not provide an accurate description of the entire part's average grain size or grain size variation. This project is designed to develop a non-destructive acoustic scanning technique, using Chirp waveforms, to quantify average grain size and grain size variation across the surface of a cast material. A Chirp is a signal in which the frequency increases or decreases over time (frequency modulation). As a Chirp passes through a material, the material's grains reduce the signal (attenuation) by absorbing the signal energy. Geophysics research has shown a direct correlation with Chirp wave attenuation and mean grain size in geological structures. The goal of this project is to demonstrate that Chirp waveform attenuation can be used to measure grain size and grain variation in cast metals (uranium and other materials of interest). An off-axis ultrasonic inspection technique using air-coupled ultrasonics has been developed to determine grain size in cast materials. The technique gives a uniform response across the volume of the component. This technique has been demonstrated to provide generalized trends of grain variation over the samples investigated.

  12. Degradation of the ethyl glucuronide content in hair by hydrogen peroxide and a non-destructive assay for oxidative hair treatment using infra-red spectroscopy.

    PubMed

    Ammann, Dominic; Becker, Roland; Kohl, Anka; Hänisch, Jessica; Nehls, Irene

    2014-11-01

    The assessment of quantification results of the alcohol abuse marker ethyl glucuronide (EtG) in hair in comparison to the cut-off values for the drinking behavior may be complicated by cosmetic hair bleaching. Thus, the impact of increasing exposure to hydrogen peroxide on the EtG content of hair was investigated. Simultaneously, the change of absorbance in the range of 1000-1100 cm(-1) indicative for the oxidation of cystine was investigated non-destructively by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) using pulverized portions of the respective hair samples. Hair samples treated with hydrogen peroxide consistently displayed a significantly increased absorbance at 1040 cm(-1) associated with the formation of cysteic acid. The EtG content decreased significantly if the hair was treated with alkaline hydrogen peroxide as during cosmetic bleaching. It could be shown that ATR-FTIR is capable of detecting an exposure to hydrogen peroxide when still no brightening was visible and already before the EtG content deteriorated significantly. Thus, hair samples suspected of having been exposed to oxidative treatment may be checked non-destructively by a readily available technique. This assay is also possible retrospectively after EtG extraction and using archived samples.

  13. Health impact assessment of air pollution using a dynamic exposure profile: Implications for exposure and health impact estimates

    SciTech Connect

    Dhondt, Stijn; Beckx, Carolien; Degraeuwe, Bart; Lefebvre, Wouter; Kochan, Bruno; Bellemans, Tom; Int Panis, Luc; Macharis, Cathy; Putman, Koen

    2012-09-15

    In both ambient air pollution epidemiology and health impact assessment an accurate assessment of the population exposure is crucial. Although considerable advances have been made in assessing human exposure outdoors, the assessments often do not consider the impact of individual travel behavior on such exposures. Population-based exposures to NO{sub 2} and O{sub 3} using only home addresses were compared with models that integrate all time-activity patterns-including time in commute-for Flanders and Brussels. The exposure estimates were used to estimate the air pollution impact on years of life lost due to respiratory mortality. Health impact of NO{sub 2} using an exposure that integrates time-activity information was on average 1.2% higher than when assuming that people are always at their home address. For ozone the overall estimated health impact was 0.8% lower. Local differences could be much larger, with estimates that differ up to 12% from the exposure using residential addresses only. Depending on age and gender, deviations from the population average were seen. Our results showed modest differences on a regional level. At the local level, however, time-activity patterns indicated larger differences in exposure and health impact estimates, mainly for people living in more rural areas. These results suggest that for local analyses the dynamic approach can contribute to an improved assessment of the health impact of various types of pollution and to the understanding of exposure differences between population groups. - Highlights: Black-Right-Pointing-Pointer Exposure to ambient air pollution was assessed integrating population mobility. Black-Right-Pointing-Pointer This dynamic exposure was integrated into a health impact assessment. Black-Right-Pointing-Pointer Differences between the dynamic and residential exposure were quantified. Black-Right-Pointing-Pointer Modest differences in health impact were found at a regional level. Black

  14. Minimizing Air Pollution Exposure: A Practical Policy to Protect Vulnerable Older Adults from Death and Disability.

    PubMed

    Woodward, Nick; Levine, Morgan

    2016-02-01

    Air pollution causes an estimated 200,000 deaths per year in the United States alone. Older adults are at greater risk of mortality caused by air pollution. Here we quantify the number of older adult facilities in Los Angeles County that are exposed to high levels of traffic derived air pollution, and propose policy solutions to reduce pollution exposure to this vulnerable subgroup. Distances between 20,362 intersections and 858 elder care facilities were estimated, and roads or highways within 500 of facilities were used to estimate traffic volume exposure. Of the 858 facilities, 54 were located near at least one major roadway, defined as a traffic volume over 100,000 cars/day. These 54 facilities house approximately 6,000 older adults. Following standards established for schools, we recommend legislation mandating the placement of new elder care facilities a minimum of 500 feet from major roadways in order to reduce unnecessary mortality risk from pollution exposure.

  15. Minimizing Air Pollution Exposure: A Practical Policy to Protect Vulnerable Older Adults from Death and Disability

    PubMed Central

    Woodward, Nick; Levine, Morgan

    2015-01-01

    Air pollution causes an estimated 200,000 deaths per year in the United States alone. Older adults are at greater risk of mortality caused by air pollution. Here we quantify the number of older adult facilities in Los Angeles County that are exposed to high levels of traffic derived air pollution, and propose policy solutions to reduce pollution exposure to this vulnerable subgroup. Distances between 20,362 intersections and 858 elder care facilities were estimated, and roads or highways within 500 of facilities were used to estimate traffic volume exposure. Of the 858 facilities, 54 were located near at least one major roadway, defined as a traffic volume over 100,000 cars/day. These 54 facilities house approximately 6,000 older adults. Following standards established for schools, we recommend legislation mandating the placement of new elder care facilities a minimum of 500 feet from major roadways in order to reduce unnecessary mortality risk from pollution exposure. PMID:26640413

  16. Prenatal Exposure to Air Pollutants Raises Risk of ADHD-Related Problems in Childhood

    EPA Pesticide Factsheets

    Researchers at the EPA/NIEHS Columbia Center for Children’s Environmental Health found that prenatal exposure to air pollutants can increase the risk of behavioral problems related to attention deficit hyperactivity disorder (ADHD) in children.

  17. Rapid microRNA changes in airways of human volunteers after controlled exposure to air pollutants

    EPA Science Inventory

    Introduction/Rationale: Exposure to air pollutants, including ozone and diesel exhaust (DE) are known to cause acute cardiopulmonary dysfunction; however, the molecular mechanisms underlying these changes remain elusive. One mechanism for rapid regulation of multiple genes is a...

  18. Rapid microRNA changes in airways of human volunteers after controlled exposure to air pollutants

    EPA Science Inventory

    Introduction/Rationale: Exposure to air pollutants, including ozone and diesel exhaust (DE) are known to cause acute cardiopulmonary dysfunction; however, the molecular mechanisms underlying these changes remain elusive. One mechanism for rapid regulation of multiple genes is a...

  19. Vascular function and short-term exposure to fine particulate air pollution.

    PubMed

    Pope, C Arden; Hansen, Jaron C; Kuprov, Roman; Sanders, Matthew D; Anderson, Michael N; Eatough, Delbert J

    2011-08-01

    Exposure to fine particulate air pollution has been implicated as a risk factor for cardiopulmonary disease and mortality. Proposed biological pathways imply that particle-induced pulmonary and systemic inflammation play a role in activating the vascular endothelium and altering vascular function. Potential effects of fine particulate pollution on vascular function are explored using controlled chamber exposure and uncontrolled ambient exposure. Research subjects included four panels with a total of 26 healthy nonsmoking young adults. On two study visits, at least 7 days apart, subjects spent 3 hr in a controlled-exposure chamber exposed to 150-200 microg/m3 of fine particles generated from coal or wood combustion and 3 hr in a clean room, with exposure and nonexposure periods alternated between visits. Baseline, postexposure, and post-clean room reactive hyperemia-peripheral arterial tonometry (RH-PAT) was conducted. A microvascular responsiveness index, defined as the log of the RH-PAT ratio, was calculated. There was no contemporaneous vascular response to the few hours of controlled exposure. Declines in vascular response were associated with elevated ambient exposures for the previous 2 days, especially for female subjects. Cumulative exposure to real-life fine particulate pollution may affect vascular function. More research is needed to determine the roles of age and gender, the effect of pollution sources, the importance of cumulative exposure over a few days versus a few hours, and the lag time between exposure and response.

  20. "Development of Model-Based Air Pollution Exposure Metrics for use in Epidemiologic Studies"

    EPA Science Inventory

    Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

  1. A Behavioral Intervention to Reduce Child Exposure to Indoor Air Pollution: Identifying Possible Target Behaviors

    ERIC Educational Resources Information Center

    Barnes, Brendon R.; Mathee, Angela; Shafritz, Lonna B.; Krieger, Laurie; Zimicki, Susan

    2004-01-01

    Indoor air pollution has been causally linked to acute lower respiratory infections in children younger than 5. The aim of this study was to identify target behaviors for a behavioral intervention to reduce child exposure to indoor air pollution by attempting to answer two research questions: Which behaviors are protective of child respiratory…

  2. DEVELOPMENT OF MODEL-BASED AIR POLLUTION EXPOSURE METRICS FOR USE IN EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

  3. "Development of Model-Based Air Pollution Exposure Metrics for use in Epidemiologic Studies"

    EPA Science Inventory

    Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

  4. DEVELOPMENT OF MODEL-BASED AIR POLLUTION EXPOSURE METRICS FOR USE IN EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

  5. CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP): AN OVERVIEW

    EPA Science Inventory

    Young children may have greater exposures to pollutants in their everyday environments than do adults. Because of their immaturity, rapid development, and smaller body masses, children may also be more susceptible to the effects of these pollutants. Recent federal health init...

  6. A Behavioral Intervention to Reduce Child Exposure to Indoor Air Pollution: Identifying Possible Target Behaviors

    ERIC Educational Resources Information Center

    Barnes, Brendon R.; Mathee, Angela; Shafritz, Lonna B.; Krieger, Laurie; Zimicki, Susan

    2004-01-01

    Indoor air pollution has been causally linked to acute lower respiratory infections in children younger than 5. The aim of this study was to identify target behaviors for a behavioral intervention to reduce child exposure to indoor air pollution by attempting to answer two research questions: Which behaviors are protective of child respiratory…

  7. Towards participatory air pollution exposure assessment in a goods movement community

    Treesearch

    Michelle C. Kondo; Chris Mizes; John Lee; Jacqueline McGady-Saier; Lisa O' Malley; Ariel Diliberto; Igor. Burstyn

    2014-01-01

    Air pollution from diesel truck traffic travelling to and from port facilities is a major environmental health concern in areas of Philadelphia such as the Port Richmond neighborhood. Ambient monitoring has limited capability to assess neighborhood- or personal-level exposures to this pollution. We sought to conduct a pilot study using a community-based participatory...

  8. CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP): AN OVERVIEW

    EPA Science Inventory

    Young children may have greater exposures to pollutants in their everyday environments than do adults. Because of their immaturity, rapid development, and smaller body masses, children may also be more susceptible to the effects of these pollutants. Recent federal health init...

  9. EXPOSURE TO PARTICULATE MATTER, VOLATILE ORGANIC COMPOUNDS, AND OTHER AIR POLLUTANTS INSIDE PATROL CARS

    EPA Science Inventory

    People driving in a vehicle might receive an enhanced dose of mobile source pollutants that are considered a potential risk for cardiovascular diseases. The exposure to components of air pollution in highway patrol vehicles, at an ambient, and a roadside location was determined d...

  10. EXPOSURE TO PARTICULATE MATTER, VOLATILE ORGANIC COMPOUNDS, AND OTHER AIR POLLUTANTS INSIDE PATROL CARS

    EPA Science Inventory

    People driving in a vehicle might receive an enhanced dose of mobile source pollutants that are considered a potential risk for cardiovascular diseases. The exposure to components of air pollution in highway patrol vehicles, at an ambient, and a roadside location was determined d...

  11. Assessment of inhalation exposure to indoor air pollutants: Screening for health risks of multiple pollutants in Japanese dwellings.

    PubMed

    Azuma, Kenichi; Uchiyama, Iwao; Uchiyama, Shigehisa; Kunugita, Naoki

    2016-02-01

    Over the past few decades, multiple low level indoor pollutants have been found in domestic dwellings. The types and concentrations of these indoor pollutants have not been consistent over time and have changed with alterations in lifestyle, the development of novel products used in housing, and the development of new measurement technologies. To clarify the highest risk pollutants for which health risks should be reduced, we conducted a health risk assessment of 49 indoor air pollutants measured in 602 houses during winter and summer from 2012 to 2014. Inhalation reference concentrations were determined, and the margins of exposure were estimated for each indoor pollutant from measured indoor air concentrations. Health risks due to ammonia and acidic gases, including formic acid, acetic acid, and hydrogen chloride, were also assessed. Overall, during both winter and summer, the highest risk pollutants were acrolein, nitrogen dioxide, benzene, formic acid, and hydrogen chloride. The health risks of propanal, acetaldehyde, and 1,4-dichlorobenzene were also high. Principal component analysis (PCA) suggested an independent principal component for 1,4-dichlorobenzene. The primary source of exposure to 1,4-dichlorobenzene in Japan is an indoor household insect repellent. The improvement of individual lifestyle and housing may be appropriate targets for reducing the risk associated with this compound. The provision of further information on the risk to consumers and promotion of changes in consumer consciousness are needed. PCA suggested that the health risks of indoor air pollutants are amalgamated into similar chemical families, such as aldehydes, aliphatic hydrocarbons, aromatic hydrocarbons, or acetic esters. Our results suggest that health-based guidelines or source control measures, based on these chemical families and similar health endpoints, are appropriate for reducing total health risk due to multiple low level indoor pollutants. Copyright © 2015 Elsevier Inc

  12. Air pollution exposure: Who is at high risk?

    NASA Astrophysics Data System (ADS)

    Peled, Ronit

    2011-04-01

    This article reviews the sub-population groups who are at high risk and first to be harmed by air pollution coming from anthropogenic combustions. Epidemiological studies from the last few decades contributed to the understanding of the different levels of susceptibility to air pollution. Older people and young infants, people who suffer from allergies, pulmonary and heart diseases, pregnant women and newborn babies, and deprived populations that suffer from low socio-economic status have all been described as populations at risk. A better understanding of the role of air pollution on large as well as specific populations' health, will promote a better protection policy.

  13. Accumulative effects of indoor air pollution exposure on leukocyte telomere length among non-smokers.

    PubMed

    Lin, Nan; Mu, Xinlin; Wang, Guilian; Ren, Yu'ang; Su, Shu; Li, Zhiwen; Wang, Bin; Tao, Shu

    2017-08-01

    Indoor air pollution is an important environmental factor that contributes to the burden of various diseases. Long-term exposure to ambient air pollution is associated with telomere shortening. However, the association between chronic indoor air pollution from household fuel combustion and leukocyte telomere length has not been studied. In our study, 137 cancer-free non-smokers were recruited. Their exposure levels to indoor air pollution from 1985 to 2014 were assessed using a face-to-face interview questionnaire, and leukocyte telomere length (LTL) was measured using a monochrome multiplex quantitative PCR method. Accumulative exposure to solid fuel usage for cooking was negatively correlated with LTL. The LTL of residents who were exposed to solid fuel combustion for three decades (LTL = 0.70 ± 0.17) was significantly shorter than that of other populations. In addition, education and occupation were related to both exposure to solid fuel and LTL. Sociodemographic factors may play a mediating role in the correlation between leukocyte telomere length and environmental exposure to indoor air pollution. In conclusion, long-term exposure to indoor air pollution may cause LTL dysfunction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Non-destructive infrared analyses: a method for provenance analyses of sandstones

    NASA Astrophysics Data System (ADS)

    Bowitz, Jörg; Ehling, Angela

    2008-12-01

    Infrared spectroscopy (IR spectroscopy) is commonly applied in the laboratory for mineral analyses in addition to XRD. Because such technical efforts are time and cost consuming, we present an infrared-based mobile method for non-destructive mineral and provenance analyses of sandstones. IR spectroscopy is based on activating chemical bonds. By irradiating a mineral mixture, special bonds are activated to vibrate depending on the bond energy (resonance vibration). Accordingly, the energy of the IR spectrum will be reduced thereby generating an absorption spectrum. The positions of the absorption maxima within the spectral region indicate the type of the bonds and in many cases identify minerals containing these bonds. The non-destructive reflection spectroscopy operates in the near infrared region (NIR) and can detect all common clay minerals as well as sulfates, hydroxides and carbonates. The spectra produced have been interpreted by computer using digital mineral libraries that have been especially collected for sandstones. The comparison of all results with XRD, RFA and interpretations of thin sections demonstrates impressively the accuracy and reliability of this method. Not only are different minerals detectable, but also differently ordered kaolinites and varieties of illites can be identified by the shape and size of the absorption bands. Especially clay minerals and their varieties in combination with their relative contents form the characteristic spectra of sandstones. Other components such as limonite, hematite and amorphous silica also influence the spectra. Sandstones, similar in colour and texture, often can be identified by their characteristic reflectance spectra. Reference libraries with more than 60 spectra of important German sandstones have been created to enable entirely computerized interpretations and identifications of these dimension stones. The analysis of infrared spectroscopy results is demonstrated with examples of different sandstones

  15. Exposure to Air Pollution Enhances the Generation of Vascular Microparticles

    EPA Science Inventory

    Epidemiological studies associate exposure to ambient levels of particulate matter (PM) with cardiovascular morbidity and mortality. The biological mechanisms by which PM exposure induces cardiovascular effects remain to be elucidated. One important limitation is the lack of sens...

  16. Exposure to Air Pollution Enhances the Generation of Vascular Microparticles

    EPA Science Inventory

    Epidemiological studies associate exposure to ambient levels of particulate matter (PM) with cardiovascular morbidity and mortality. The biological mechanisms by which PM exposure induces cardiovascular effects remain to be elucidated. One important limitation is the lack of sens...

  17. Characterization of protein expression of Platanus pollen following exposure to gaseous pollutants and vehicle exhaust particles.

    PubMed

    Lu, Senlin; Ren, Jingjin; Hao, Xiaojie; Liu, Dingyu; Zhang, Rongci; Wu, Minghong; Yi, Fei; Lin, Jun; Shinich, Yonemochi; Wang, Qingyue

    2014-01-01

    Being major ornamental street trees, species of Platanus are widely planted in the Shanghai urban area. A great deal of allergenic Platanus pollen is released from the trees and suspended in the atmosphere during its flowering season, ultimately causing allergic respiratory diseases. Few papers have focused on the distribution of this type of pollen and its expression of allergenic proteins. In order to investigate any differences in protein expression in Platanus pollen following exposure to gaseous and particulate pollutants, a special apparatus was designed. Exposure condition (such as temperature, humidity, and exposure time) of Platanus pollen and gaseous pollutants can be simulated using of this apparatus. Fresh Platanus orientalis pollen, pollutant gases (NO2, SO2, NH3), and typical urban ambient particles (vehicle exhaust particles, VEPs) were mixed in this device to examine possible changes that might occur in ambient airborne urban pollen following exposure to such pollutants. Our results showed that the fresh P. orientalis pollen became swollen, and new kinds of particles could be found on the surface of the pollen grains after exposure to the pollutants. The results of SDS-PAGE showed that five protein bands with molecular weights of 17-19, 34, 61, 82, and 144 kDa, respectively, were detected and gray scale of these brands increased after the pollen exposure to gaseous pollutants. The two-dimensional gel electrophoresis analysis demonstrated that a Platanus pollen allergenic protein (Pla a1, with a molecular weight of 18 kDa) increased in abundance following exposure to pollutant gases and VEPs, implying that air pollutants may exacerbate the allergenicity of pollen.

  18. Exposure to Moderate Air Pollution during Late Pregnancy and Cord Blood Cytokine Secretion in Healthy Neonates

    PubMed Central

    Latzin, Philipp; Frey, Urs; Armann, Jakob; Kieninger, Elisabeth; Fuchs, Oliver; Röösli, Martin; Schaub, Bianca

    2011-01-01

    Background/Objectives Ambient air pollution can alter cytokine concentrations as shown in vitro and following short-term exposure to high air pollution levels in vivo. Exposure to pollution during late pregnancy has been shown to affect fetal lymphocytic immunophenotypes. However, effects of prenatal exposure to moderate levels of air pollutants on cytokine regulation in cord blood of healthy infants are unknown. Methods In a birth cohort of 265 healthy term-born neonates, we assessed maternal exposure to particles with an aerodynamic diameter of 10 µm or less (PM10), as well as to indoor air pollution during the last trimester, specifically the last 21, 14, 7, 3 and 1 days of pregnancy. As a proxy for traffic-related air pollution, we determined the distance of mothers' homes to major roads. We measured cytokine and chemokine levels (MCP-1, IL-6, IL-10, IL-1ß, TNF-α and GM-CSF) in cord blood serum using LUMINEX technology. Their association with pollution levels was assessed using regression analysis, adjusted for possible confounders. Results Mean (95%-CI) PM10 exposure for the last 7 days of pregnancy was 18.3 (10.3–38.4 µg/m3). PM10 exposure during the last 3 days of pregnancy was significantly associated with reduced IL-10 and during the last 3 months of pregnancy with increased IL-1ß levels in cord blood after adjustment for relevant confounders. Maternal smoking was associated with reduced IL-6 levels. For the other cytokines no association was found. Conclusions Our results suggest that even naturally occurring prenatal exposure to moderate amounts of indoor and outdoor air pollution may lead to changes in cord blood cytokine levels in a population based cohort. PMID:21826232

  19. Disrupted Nitric Oxide Metabolism from Type II Diabetes and Acute Exposure to Particulate Air Pollution.

    PubMed

    Pettit, Ashley P; Kipen, Howard; Laumbach, Robert; Ohman-Strickland, Pamela; Kelly-McNeill, Kathleen; Cepeda, Clarimel; Fan, Zhi-Hua; Amorosa, Louis; Lubitz, Sara; Schneider, Stephen; Gow, Andrew

    2015-01-01

    Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO) has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46-70 years) were taken on a 1.5 hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics.

  20. Disrupted Nitric Oxide Metabolism from Type II Diabetes and Acute Exposure to Particulate Air Pollution

    PubMed Central

    Pettit, Ashley P.; Kipen, Howard; Laumbach, Robert; Ohman-Strickland, Pamela; Kelly-McNeill, Kathleen; Cepeda, Clarimel; Fan, Zhi-Hua; Amorosa, Louis; Lubitz, Sara; Schneider, Stephen; Gow, Andrew

    2015-01-01

    Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO) has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46–70 years) were taken on a 1.5hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics. PMID:26656561

  1. A review of traffic-related air pollution exposure assessment studies in the developing world.

    PubMed

    Han, Xianglu; Naeher, Luke P

    2006-01-01

    Exposure assessment studies in the developing world are important. Although recent years have seen an increasing number of traffic-related pollution exposure studies, exposure assessment data on this topic are still limited. Differences among measuring methods and a lack of strict quality control in carrying out exposure assessment make it difficult to generalize and compare findings between studies. In this article, exposure assessment studies carried out in the developing world on several traffic-related air pollutants are reviewed. These pollutants include particulate matter (PM), carbon monoxide (CO), nitrogen dioxide (NO(2)), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). In addition, it discusses advantages and disadvantages of various monitoring methods (ambient fixed-site monitoring, microenvironment monitoring, and personal exposure assessment using portable samplers) for these pollutants in exposure assessment studies. Also included in this paper is a brief introduction of standards for these pollutants in ambient air or in occupational settings established by the United States Environmental Protection Agency (USEPA), the United States Occupational Safety and Health Administration (OSHA) and the World Health Organization (WHO). The review ends with a summary of the limitations and gaps in recent studies and suggestions for future research in the developing world.

  2. Air pollution exposure: a novel environmental risk factor for interstitial lung disease?

    PubMed

    Johannson, Kerri A; Balmes, John R; Collard, Harold R

    2015-04-01

    Air pollution exposure is a well-established risk factor for several adverse respiratory outcomes, including airways diseases and lung cancer. Few studies have investigated the relationship between air pollution and interstitial lung disease (ILD) despite many forms of ILD arising from environmental exposures. There are potential mechanisms by which air pollution could cause, exacerbate, or accelerate the progression of certain forms of ILD via pulmonary and systemic inflammation as well as oxidative stress. This article will review the current epidemiologic and translational data supporting the plausibility of this relationship and propose a new conceptual framework for characterizing novel environmental risk factors for these forms of lung disease.

  3. Associations between lifestyle and air pollution exposure: Potential for confounding in large administrative data cohorts.

    PubMed

    Strak, Maciej; Janssen, Nicole; Beelen, Rob; Schmitz, Oliver; Karssenberg, Derek; Houthuijs, Danny; van den Brink, Carolien; Dijst, Martin; Brunekreef, Bert; Hoek, Gerard

    2017-07-01

    Cohorts based on administrative data have size advantages over individual cohorts in investigating air pollution risks, but often lack in-depth information on individual risk factors related to lifestyle. If there is a correlation between lifestyle and air pollution, omitted lifestyle variables may result in biased air pollution risk estimates. Correlations between lifestyle and air pollution can be induced by socio-economic status affecting both lifestyle and air pollution exposure. Our overall aim was to assess potential confounding by missing lifestyle factors on air pollution mortality risk estimates. The first aim was to assess associations between long-term exposure to several air pollutants and lifestyle factors. The second aim was to assess whether these associations were sensitive to adjustment for individual and area-level socioeconomic status (SES), and whether they differed between subgroups of the population. Using the obtained air pollution-lifestyle associations and indirect adjustment methods, our third aim was to investigate the potential bias due to missing lifestyle information on air pollution mortality risk estimates in administrative cohorts. We used a recent Dutch national health survey of 387,195 adults to investigate the associations of PM10, PM2.5, PM2.5-10, PM2.5 absorbance, OP(DTT,) OP(ESR) and NO2 annual average concentrations at the residential address from land use regression models with individual smoking habits, alcohol consumption, physical activity and body mass index. We assessed the associations with and without adjustment for neighborhood and individual SES characteristics typically available in administrative data cohorts. We illustrated the effect of including lifestyle information on the air pollution mortality risk estimates in administrative cohort studies using a published indirect adjustment method. Current smoking and alcohol consumption were generally positively associated with air pollution. Physical activity and

  4. Characterization and comparison of defects detection limits of three ultrasonic non destructive methods

    NASA Astrophysics Data System (ADS)

    Péronnet, E.; Eyma, F.; Welemane, H.; Pescay, C.

    2010-06-01

    This work deals with the Liquid Resin Infusion (LRI) process developed within the research program “FUSelage COMPosite” of DAHER SOCATA. This manufacturing process enables the realization of complex composite structures or fuselage elements in a single phase (mono-material), which considerably reduce connections and relative difficulties. The concern here is the investigation of non destructive testing (NDT) methods that can be applied to LRI-structures in order to define their capacities for defect detection, and especially their associated critical defect size. In aviation industry, the AITM standards require the ultrasonic testing as NDT for composite materials. Therefore the aim of this work is to characterize and compare three different and complementary ultrasonic techniques on composite specimens. Such analysis allows to define the NDT application field of each method in term of defect detection.

  5. High-Tc planar SQUID gradiometer for eddy current non-destructive evaluation

    NASA Astrophysics Data System (ADS)

    Zhang, Ming-Jian; Lang, Pei-Lin; Peng, Zhi-Hui; Chen, Ying-Fei; Chen, Ke; Zheng, Dong-Ning

    2006-08-01

    This paper reports the fabrication and test of a high-Tc SQUID planar gradiometer which is patterned from YBCO thin film deposited on a SrTiO3 bicrystal substrate. The measurement of noise spectrum at 77K shows that the white noise at 200 Hz is about 1×10-4Φ0/(Hz)1/2. The minimal magnetic gradient is measured and the results suggest that the minimal magnetic gradient is 94 pT/m. The planar gradiometer is used in non-destructive evaluation (NDE) experiments to detect the artifacts in conducting aluminium plates by performing eddy current testing in an unshielded environment. The effect of the exciting coil dimension on the NDE results is investigated. By mapping out the induced field distribution, flaws about 10mm below the plate surface can be clearly identified.

  6. Research on high-Tc SQUID based non-destructive evaluation

    NASA Astrophysics Data System (ADS)

    Wang, Hui-Wu; Kong, Xiang-Yan; Ren, Yu-Feng; Yu, Hong-Wei; Ding, Hong-Sheng; Zhao, Shi-Ping; Chen, Geng-Hua; Zhou, Yue-Liang; Zhang, Li-Hua; He, Yu-Sheng; Yang, Qian-Sheng

    2004-01-01

    A non-destructive evaluation system based on high-Tc dc-SQUID (superconducting quantum interference device) incorporating a gradient field excitation has been built. By using this system a 1mm-diameter hole at a depth of 2mm inside an aluminium plate at room temperature can be easily detected and imaged in an unshielded environment. The relation between the spatial resolution, or the smallest detectable flaw size and experimental parameters is briefly analysed in terms of a simple metal ring model. The result shows that the spatial resolution depends strongly on the sensor-sample separation as well as on some other parameters, such as signal-to-noise ratio of excitation, excitation frequency and material conductivity.

  7. Correlation-based imaging technique using ultrasonic transmit-receive array for Non-Destructive Evaluation.

    PubMed

    Quaegebeur, Nicolas; Masson, Patrice

    2012-12-01

    This paper describes a novel array post-processing method for Non-Destructive Evaluation (NDE) using phased-array ultrasonic probes. The approach uses the capture and processing of the full matrix of all transmit-receive time-domain signals from a transducer array as in the case of the Total Focusing Method (TFM), referred as the standard of imaging algorithms. The proposed technique is based on correlation of measured signals with theoretical propagated signals computed over a given grid of points. In that case, real-time imaging can be simply implemented using discrete signal product. The advantage of the present technique is to take into account transducer directivity, dynamics and complex propagation patterns, such that the number of required array elements for a given imaging performance can be greatly reduced. Numerical and experimental application to contact inspection of isotropic structure is presented and real-time implementation issues are discussed.

  8. Non-Destructive Evaluation of Thermal Spray Coating Interface Quality By Eddy Current Method

    SciTech Connect

    B. Mi; G. Zhao; R. Bayles

    2006-08-10

    Thermal spray coating is usually applied through directing molten or softened particles at very high velocities onto a substrate. An eddy current non-destructive inspection technique is presented here for thermal spray coating interface quality characterization. Several high-velocity-oxy-fuel (HVOF) coated steel plates were produced with various surface preparation conditions or spray process parameters. A quad-frequency eddy current probe was used to manually scan over the coating surface to evaluate the bonding quality. Experimental results show that different surface preparation conditions and varied process parameters can be successfully differentiated by the impedance value observed from the eddy current probe. The measurement is fairly robust and consistent. This non-contact, nondestructive, easy-to-use technique has the potential for evaluating the coating quality immediately after its application so that any defects can be corrected immediately.

  9. Could non-destructive methodologies enhance the microbiologically influenced corrosion (MIC) in pipeline systems?

    NASA Astrophysics Data System (ADS)

    Al-Abbas, F.; Kakpovbia, A.; Mishra, B.; Olson, D.; Spear, J.

    2013-01-01

    Stringent corrosion management programs are being deployed by oil and gas industry to ensure the integrity of pipeline systems. Parts of this program are the corrosion protection systems and inspection detection methods included non-destructive techniques. Those measures induce remnant magnetic field (RMF) in the pipeline steel. Potentially the RMF could affect the corrosion process in the pipeline including microbiologically influenced corrosion (MIC). Microorganisms in pipelines have surface charges and produce a wide variety of metabolic products. Consequently, when they are exposed to RMF generated at the linepipe steel surface by the aforementioned sources there will be potential effects. This sequentially will increase the likelihood of biofilm formation and hence enhance/promote MIC. This study investigates the potential effects of RFM on the MIC by sulfate reducing bacteria (SRB).

  10. Non-destructive electron microscopy imaging and analysis of biological samples with graphene coating

    NASA Astrophysics Data System (ADS)

    Park, Jong Bo; Kim, Yong-Jin; Kim, Seong-Min; Yoo, Je Min; Kim, Youngsoo; Gorbachev, Roman; Barbolina, I. I.; Kim, Sang Jin; Kang, Sangmin; Yoon, Myung-Han; Cho, Sung-Pyo; Novoselov, Konstantin S.; Hong, Byung Hee

    2016-12-01

    In electron microscopy (EM), charging of non-conductive biological samples by focused electron beams hinders their high-resolution imaging. Gold or platinum coatings have been commonly used to prevent such sample charging, but it disables further quantitative and qualitative chemical analyses such as energy dispersive spectroscopy (EDS). Here we report that graphene-coating on biological samples enables non-destructive high-resolution imaging by EM as well as chemical analysis by EDS, utilizing graphene’s transparency to electron beams, high conductivity, outstanding mechanical strength and flexibility. We believe that the graphene-coated imaging and analysis would provide us a new opportunity to explore various biological phenomena unseen before due to the limitation in sample preparation and image resolution, which will broaden our understanding on the life mechanism of various living organisms.

  11. Contribution to the improvement of heritage mural painting non-destructive testing by stimulated infrared thermography

    NASA Astrophysics Data System (ADS)

    Bodnar, Jean-Luc; Mouhoubi, Kamel; Di Pallo, Luigi; Detalle, Vincent; Vallet, Jean-Marc; Duvaut, Thierry

    2013-10-01

    Non-destructive testing of heritage mural paintings by means of stimulated infrared thermography has now become rather efficient [1-14]. However, pigments, which form a pictorial layer, have contrasting radiative properties possibly leading to artifact detection. In this paper, attempts to alleviate this difficulty are presented. Based on the spectroscopic study of different paint layers, one can argue that, in the medium infrared field, this radiative disparity decreases significantly. Then, with similar settings, it can be shown that ceramic radiative sources allow reaching this wavelength band. Finally, on the basis of a study carried out on an academic sample and a partial copy of a fresco from the cathedral of Angers, combining ceramic heat sources with a laboratory SAMMTHIR experimental setup enables to make real headway in terms of defects' detection.

  12. PREDICTION OF DISSOLVER LIFETIMES THROUGH NON-DESTRUCTIVE EVALUATION AND LABORATORY TESTING

    SciTech Connect

    Mickalonis, J.; Woodsmall, T.; Hinz, W.; Edwards, T.

    2011-10-03

    Non-destructive evaluation was used as the primary method of monitoring the corrosion degradation of nuclear material dissolvers and assessing the remaining lifetimes. Materials were typically processed in nitric acid based (4-14M) solutions containing fluoride concentrations less than 0.2 M. The primary corrosion issue for the stainless steel dissolvers is the occurrence of localized corrosion near the tank bottom and the heat affected zones of the welds. Laboratory data for a range of operational conditions, including solution chemistry and temperature, was used to assess the impact of processing changes on the dissolver corrosion rate. Experimental and NDE-based general corrosion rates were found to be in reasonable agreement for standard dissolution chemistries consisting of nitric acid with fluorides and at temperatures less than 95 C. Greater differences were observed when chloride was present as an impurity and temperatures exceeded 100 C.

  13. System and method for non-destructive evaluation of surface characteristics of a magnetic material

    DOEpatents

    Jiles, David C.; Sipahi, Levent B.

    1994-05-17

    A system and a related method for non-destructive evaluation of the surface characteristics of a magnetic material. The sample is excited by an alternating magnetic field. The field frequency, amplitude and offset are controlled according to a predetermined protocol. The Barkhausen response of the sample is detected for the various fields and offsets and is analyzed. The system produces information relating to the frequency content, the amplitude content, the average or RMS energy content, as well as count rate information, for each of the Barkhausen responses at each of the excitation levels applied during the protocol. That information provides a contiguous body of data, heretofore unavailable, which can be analyzed to deduce information about the surface characteristics of the material at various depths below the surface.

  14. Barkhausen spectroscopy: Non-destructive characterization of magnetic materials as a function of depth

    NASA Astrophysics Data System (ADS)

    Kypris, O.; Nlebedim, I. C.; Jiles, D. C.

    2014-05-01

    In this study, we conceptually divided a ferromagnetic specimen into layers along its depth. For each layer, we derived a non-linear integral equation that describes the attenuation with frequency and distance of magnetic Barkhausen emissions coming from that layer. We postulate that the Barkhausen spectrum measured at the surface by an induction coil can be expressed as the sum of the individual layer spectra. We show how a non-linear least squares algorithm can be used to recover the properties in individual layers. These are related to stress using an extension to the theory of ferromagnetic hysteresis. We found that the quality of the fit is influenced by the sensitivity of the ferromagnetic material to strain, as well as by the sensor-specimen coupling. The proposed method can be used for the non-destructive characterization of stress as a function of depth in magnetic materials.

  15. Model-based non-destructive investigation methods in semiconductor industry

    NASA Astrophysics Data System (ADS)

    Bilski, B.; Paz, V. Ferreras; Frenner, K.; Osten, W.

    2013-05-01

    Scatterometry is an investigation method that is gaining in importance in semiconductor industry. As an optical method it has distinct advantages that its competitor-methods do not possess: the ability for a quick and non-destructive measurement of fine features fabricated by modern generations of lithography machines. Scatterometry is very distinct from other measurement techniques also in this respect that it is a model-based method. As such it relies heavily on simulation and is essentially solving an inverse problem. In a forward optical measurement an imaging system processes the object information losing some fraction of information in the process. The measurement process in scatterometry follows the same pattern. The measurement result however is now compared against multiple simulated direct problems. The best fit between the simulation and the measurement is assumed to reconstruct the measured object.

  16. Incoherent scattering of gamma photons for non-destructive tomographic inspection of pipeline.

    PubMed

    Sharma, Amandeep; Sandhu, B S; Singh, Bhajan

    2010-12-01

    A scanner system, operating in a non-destructive and non-invasive way, is presented for pipeline to determine its location in land soil, wall thickness, type of liquid flowing and crack/blockage position. The present experiment simulates a real case where pipe corrosion (wall thinning) under insulation can be known from the study of incoherent scattering of 662 keV gamma photons. The incoherent scattered intensity, obtained by unfolding (deconvolution) the experimental pulse-height distribution of NaI(Tl) scintillation detector with the help of inverse response matrix, provides the desired information. The method is quite sensitive for small change (approximately 1 mm) in the thickness of pipe wall, locating a defect of 1mm width under insulation and a small change (approximately 0.1 gm cm(-3)) in the density of liquid flowing through pipe. Copyright 2010 Elsevier Ltd. All rights reserved.

  17. Gigahertz time-domain spectroscopy and imaging for non-destructive materials research and evaluation

    PubMed Central

    Bulgarevich, Dmitry S.; Shiwa, Mitsuharu; Furuya, Takashi; Tani, Masahiko

    2016-01-01

    By using optical sampling with repetition frequency modulation of pump/probe laser pulses on photoconductive emitter/detector antennas, the high-speed time/frequency domain gigahertz imaging is reported due to the absence of opto-mechanical delay line in this optical scheme. The clear contrast for a 3-cm wide metal plate, which was placed behind a 5-cm thick concrete block, was observed with a 1 × 1 mm image pixilation. On average, it took only ~0.75 s per pixel/waveform acquisition/assignment with a 675 ps time-domain window. This could become a valuable non-destructive evaluation technique in gigahertz spectral range with all benefits of time-domain spectroscopy. PMID:27302877

  18. Two-dimensional non-destructive diagnostics for accelerators by Beam Cross section Monitor

    NASA Astrophysics Data System (ADS)

    Gavrilov, S.; Feschenko, A.; Reinhardt-Nickoulin, P.; Vasilyev, I.

    2014-01-01

    The ionization Beam Cross section Monitor (BCSM) provides non-destructive measurements of transverse beam parameters in INR RAS proton linac. Operation of the monitor is based on utilization of residual gas ionization. The monitor enables to observe position, two-dimensional beam cross section, beam profiles obtained from it and emittance ellipses reconstructed from profiles data as well as their evolution in real-time within a wide range of energies and beam intensities. The BCSM design and image processing system are described. The monitor accuracy and precision analysis and estimations of influence of the linac radiation background are discussed. The available experimental results of proton beam transverse parameters measurements at the linac exit are presented.

  19. Design of ERL Spoke Cavity For Non-Destructive Assay Research

    NASA Astrophysics Data System (ADS)

    Sawamura, M.; Nagai, R.; Nishimori, N.; Hajima, R.

    2015-10-01

    We are proposing non-destructive assay system of nuclear materials with laser Compton scattering combined with an energy-recovery linac (ERL) and a laser. Since constructing accelerator system for nuclear safe guard and security requires small cavities, spoke cavities have many advantages such as shortening the distance between cavities, small frequency detune due to micro-phonics and easy adjustment of field distribution for strong cell coupling. Calculations of optimized cavity shape and HOM coupler shape have been performed and rf properties with aluminum spoke cavity model have been also measured. Considering refrigerator system required for superconducting accelerator, we are planning to develop 325MHz spoke cavity which can be practically operated with 4K liquid helium. We have started to fabricate the niobium one-spoke cavity.

  20. Portable generator-based XRF instrument for non-destructive analysis at crime scenes

    NASA Astrophysics Data System (ADS)

    Schweitzer, Jeffrey S.; Trombka, Jacob I.; Floyd, Samuel; Selavka, Carl; Zeosky, Gerald; Gahn, Norman; McClanahan, Timothy; Burbine, Thomas

    2005-12-01

    Unattended and remote detection systems find applications in space exploration, telemedicine, teleforensics, homeland security and nuclear non-proliferation programs. The National Institute of Justice (NIJ) and the National Aeronautics and Space Administration's (NASA) Goddard Space Flight Center (GSFC) have teamed up to explore the use of NASA developed technologies to help criminal justice agencies and professionals investigate crimes. The objective of the program is to produce instruments and communication networks that have application within both NASA's space program and NIJ, together with state and local forensic laboratories. A general-purpose X-ray fluorescence system has been built for non-destructive analyses of trace and invisible material at crime scenes. This portable instrument is based on a generator that can operate to 60 kV and a Schottky CdTe detector. The instrument has been shown to be successful for the analysis of gunshot residue and a number of bodily fluids at crime scenes.

  1. A rapid non-destructive method for root dentin moisture measurements

    PubMed Central

    Komabayashi, Takashi; Zhu, Qiang; Jiang, Jin; Safavi, Kamran E.; Spångberg, Larz S.W.

    2009-01-01

    Dentin moisture content is important in adhesive bonding and structural strength research. However, there is no rapid method available to assess dentin moisture without sample destruction. This study examined the use of a digital grain moisture meter to measure root dentin moisture in vitro. Extracted mandibular single rooted teeth were sectioned at the CEJ. The moisture of the root dentin was measured at six measuring modes for different grains and repeated five times. Dentin weight changes before and after drying were measured to obtain control values. The control values were compared with machine readings. In conclusion, (1) Each non-destructive measurement took less than 30 seconds. (2) 24 hours storage at 37°C and 100 % humidity did not restore dentin moisture. (3) Five grain modes had a high validity, and could be used for dentin moisture measurements. PMID:19157921

  2. Prediction of Service Life of Cordierite-Mullite Refractory Materials by Non-Destructive Methods

    SciTech Connect

    Boccaccini, D. N.; Kamseu, Elie; Cannio, M.; Romagnoli, M.; Veronesi, P.; Leonelli, C.; Volkov-Husoviae, T. D.; Dlouhy, I.; Boccaccini, A. R.

    2008-02-15

    Ultrasonic pulse velocity testing was used to perform non-destructive quality control of refractory plates used as substrates in fast firing of porcelain whitewares. The measurement of the ultrasonic velocity was used to asses the presence of internal voids or cracks originated from the manufacturing procedure. Image analysis was used to predict thermal stability of the refractory materials. Two cordierite-mullite compositions were investigated that are characterized by different microstructure morphologies and crack propagation behaviour. A brief discussion about the correlation between microstructure, crack propagation behaviour and thermal shock resistance is presented. Moreover, empirical models were developed to predict the service life of refractory plates from measured values of ultrasonic velocities in plates in the as-received state.

  3. MCNP ESTIMATE OF THE SAMPLED VOLUME IN A NON-DESTRUCTIVE IN SITU SOIL CARBON ANALYSIS.

    SciTech Connect

    WIELOPOLSKI, L.; DIOSZEGI, I.; MITRA, S.

    2004-05-03

    Global warming, promoted by anthropogenic CO{sub 2} emission into the atmosphere, is partially mitigated by the photosynthesis processes of the terrestrial echo systems that act as atmospheric CO{sub 2} scrubbers and sequester carbon in soil. Switching from till to no till soils management practices in agriculture further augments this process. Carbon sequestration is also advanced by putting forward a carbon ''credit'' system whereby these can be traded between CO{sub 2} producers and sequesters. Implementation of carbon ''credit'' trade will be further promulgated by recent development of a non-destructive in situ carbon monitoring system based on inelastic neutron scattering (INS). Volumes and depth distributions defined by the 0.1, 1.0, 10, 50, and 90 percent neutron isofluxes, from a point source located at either 5 or 30 cm above the surface, were estimated using Monte Carlo calculations.

  4. Prediction of Service Life of Cordierite-Mullite Refractory Materials by Non-Destructive Methods

    NASA Astrophysics Data System (ADS)

    Boccaccini, D. N.; Kamseu, Elie; Volkov-Husoviæ, T. D.; Cannio, M.; Romagnoli, M.; Veronesi, P.; Dlouhy, I.; Boccaccini, A. R.; Leonelli, C.

    2008-02-01

    Ultrasonic pulse velocity testing was used to perform non-destructive quality control of refractory plates used as substrates in fast firing of porcelain whitewares. The measurement of the ultrasonic velocity was used to asses the presence of internal voids or cracks originated from the manufacturing procedure. Image analysis was used to predict thermal stability of the refractory materials. Two cordierite-mullite compositions were investigated that are characterized by different microstructure morphologies and crack propagation behaviour. A brief discussion about the correlation between microstructure, crack propagation behaviour and thermal shock resistance is presented. Moreover, empirical models were developed to predict the service life of refractory plates from measured values of ultrasonic velocities in plates in the as-received state.

  5. Non-destructive thermo-mechanical behavior assessment of glass-ceramics for dental applications

    NASA Astrophysics Data System (ADS)

    Kordatos, E. Z.; Abdulkadhim, Z.; Feteira, A. M.

    2017-05-01

    Every year millions of people seek dental treatment to either repair damaged, unaesthetic and dysfunctional teeth or replace missing natural teeth. Several dental materials have been developed to meet the stringent requirements in terms of mechanical properties, aesthetics and chemical durability in the oral environment. Glass-ceramics exhibit a suitable combination of these properties for dental restorations. This research is focused on the assessment of the thermomechanical behavior of bio-ceramics and particularly lithium aluminosilicate glass-ceramics (LAS glass-ceramics). Specifically, methodologies based on Infrared Thermography (IRT) have been applied in order the structure - property relationship to be evaluated. Non-crystallized, partially crystallized and fully crystallized glass-ceramic samples have been non-destructively assessed in order their thermo-mechanical behavior to be associated with their micro-structural features.

  6. NON-DESTRUCTIVE IN SITU SOIL CARBON ANALYSIS: PRINCIPLE AND RESULTS.

    SciTech Connect

    WIELOPOLSKI, L.; MITRA, S.; HENDREY, G.; ROGERS, H.; TORBERT, A.; PRIOR, S.

    2003-05-05

    Global warming is promoted by anthropogenic CO{sub 2} emissions into the atmosphere, while at the same time it is partially mitigated by carbon sequestration by terrestrial ecosystems. However, improvement in the understanding and monitoring of below ground carbon processes is essential for evaluating strategies for carbon sequestration including quantification of carbon stores for credits. A system for non-destructive in situ carbon monitoring in soil, based on inelastic neutron scattering (INS), is described. The system can be operated in stationary or scanning mode and measures soil to depth of approximately 30 cm. There is a good agreement between results obtained from INS and standard chemical analysis of soil cores collected from the same study site.

  7. Non-destructive testing of mid-IR optical fiber using infrared imaging

    NASA Astrophysics Data System (ADS)

    Gagnon, Marc-André; Fortin, Vincent; Vallée, Réal; Farley, Vincent; Lagueux, Philippe; Guyot, Éric; Marcotte, Frédérick

    2016-05-01

    Optical fiber lasers offers the advantage of being relatively compact and efficient. However, the materials such as fluoride and chalcogenide glasses used for their fabrication must be exempt of defects in order to make efficient laser systems. However, most existing quality control techniques are not compatible with chalcogenide fibers because of their limited transparency in the visible spectral range. For this reason, the Université Laval's Centre d'optique, photonique et laser (COPL), in Quebec City, Canada, has developed a novel non-destructive testing (NDT) methodology based on infrared imaging to address this problem. The results show how this simple screening technique eases the selection of high-quality fibers for the design of high-power mid-IR lasers.

  8. Main geophysical techniques used for non-destructive evaluation in cultural built heritage: a review

    NASA Astrophysics Data System (ADS)

    Martinho, E.; Dionísio, A.

    2014-10-01

    Geophysical methodologies have been implemented, tested and validated as diagnostic and /or monitoring tools in artworks or historical monuments. They are non-destructive and can give an image of internal structure of investigated medium. This paper is a review about the main geophysical techniques applied to the study of cultural built heritage (excluding the archaeology field). A brief description of the used methodologies is presented, the main investigations done in this field are showed, the method or methods most appropriate to answer each problem (moisture detection, characterization of the materials, study of the structural continuity of the material, assessment of intervention’s effectiveness) are indicated and the main advances and gaps and future developments are also pointed out.

  9. Design status of the US 100 tesla non-destructive magnet system

    SciTech Connect

    Schneider-Muntau, H.; Eyssa, Y.; Pernambuco-Wise, P.; Boenig, H.; Campbell, L.J.; Eberl, K.R.; Parkin, D.M.; Schillig, J.; Sims, J.

    1996-09-01

    A collaborative effort is now underway in the US between the Department of Energy and the National Science Foundation to design, build, and use a 100 T non-destructive magnet for studying the properties of materials at high fields. The National High Magnetic Field Laboratory (NHMFL) at Tallahassee, Florida, and Los Alamos, New Mexico, where the magnet will be sited, is carrying out this task. This magnet will join other pulsed magnets at NHMFL, to provide magnetic fields at strengths, time durations, and volumes that are longer (in combination) than any now available. In particular, the goal for the 100 T magnet is a time duration above 80 T of about 15 ms in a cold bore of 24 mm. The present status of the design effort and various design issues are presented here.

  10. Non-destructive fraud detection in rosehip oil by MIR spectroscopy and chemometrics.

    PubMed

    Santana, Felipe Bachion de; Gontijo, Lucas Caixeta; Mitsutake, Hery; Mazivila, Sarmento Júnior; Souza, Leticia Maria de; Borges Neto, Waldomiro

    2016-10-15

    Rosehip oil (Rosa eglanteria L.) is an important oil in the food, pharmaceutical and cosmetic industries. However, due to its high added value, it is liable to adulteration with other cheaper or lower quality oils. With this perspective, this work provides a new simple, fast and accurate methodology using mid-infrared (MIR) spectroscopy and partial least squares discriminant analysis (PLS-DA) as a means to discriminate authentic rosehip oil from adulterated rosehip oil containing soybean, corn and sunflower oils in different proportions. The model showed excellent sensitivity and specificity with 100% correct classification. Therefore, the developed methodology is a viable alternative for use in the laboratory and industry for standard quality analysis of rosehip oil since it is fast, accurate and non-destructive.

  11. Rapid, non-destructive evaluation of ultrathin WSe2 using spectroscopic ellipsometry

    NASA Astrophysics Data System (ADS)

    Eichfeld, Sarah M.; Eichfeld, Chad M.; Lin, Yu-Chuan; Hossain, Lorraine; Robinson, Joshua A.

    2014-09-01

    The utilization of tungsten diselenide (WSe2) in electronic and optoelectronic devices depends on the ability to understand and control the process-property relationship during synthesis. We demonstrate that spectroscopic ellipsometry is an excellent technique for accurate, non-destructive determination of ultra-thin (<30 nm) WSe2 properties. The refractive index (n) and extinction coefficient (k) were found to be independent of thickness down to 1.3 nm, and were used to determine film thickness, which was confirmed to be within 9% of values found via atomic force microscopy. Finally, the optical bandgap was found to closely correlate with thickness, ranging from 1.2 to 1.55 eV as the WSe2 is thinned to the equivalent of 2 atomic layers.

  12. A robust approach to optimal matched filter design in ultrasonic non-destructive evaluation (NDE)

    NASA Astrophysics Data System (ADS)

    Li, Minghui; Hayward, Gordon

    2017-02-01

    The matched filter was demonstrated to be a powerful yet efficient technique to enhance defect detection and imaging in ultrasonic non-destructive evaluation (NDE) of coarse grain materials, provided that the filter was properly designed and optimized. In the literature, in order to accurately approximate the defect echoes, the design utilized the real excitation signals, which made it time consuming and less straightforward to implement in practice. In this paper, we present a more robust and flexible approach to optimal matched filter design using the simulated excitation signals, and the control parameters are chosen and optimized based on the real scenario of array transducer, transmitter-receiver system response, and the test sample, as a result, the filter response is optimized and depends on the material characteristics. Experiments on industrial samples are conducted and the results confirm the great benefits of the method.

  13. Non-destructive Imaging of Standard Cracks of Railway by Photoacoustic Piezoelectric Technology

    NASA Astrophysics Data System (ADS)

    Yan, Laijun; Gao, Chunming; Zhao, Binxing; Ma, Xingchen; Zhuang, Nan; Duan, Haiyang

    2012-11-01

    The photoacoustic piezoelectric (PAPE) technique is an effective non-destructive testing technique for detecting defects in materials. In this paper, Chinese national standard railway cracks have been detected by thermal wave imaging based on the PAPE technique. First, the theory of the PAPE technique has been introduced and the corresponding imaging principle has been analyzed. Second, the corresponding experimental system has been setup, and the imaging tests have been carried out. Third, two kinds of standard cracks have been examined by the imaging system. The results show that thermal wave imaging based on the PAPE technique can effectively image and identify the cracks at different depths, which lays a foundation for practical application to the detection of rail cracks.

  14. Laser ultrasonics for civil engineering : some applications in development for concrete non destructive testing

    NASA Astrophysics Data System (ADS)

    Abraham, O.; Popovics, J. S.; Cottineau, L.-M.; Durand, O.

    2011-01-01

    Non destructive testing of civil engineering infrastructures is becoming of primary importance for their diagnosis, residual time life estimation and/or structural health monitoring. A particularity of civil engineering application is the large size of the survey zones and the expected low cost of inspection. In this context non contact ultrasonics may offer the possibility to built robots that can automatically scan large areas (or eventually be integrated in moving vehicles) to recover mechanical properties of material or to perform imagery for geometrical information recovery. In this paper we present two possible applications of in situ laser ultrasonics : one is the detection of voids in tendon duct with the impact echo method, the other is the use of surface waves to recover mechanical properties of the first centimetres of concrete structures (here after called cover concrete).

  15. Rapid, non-destructive evaluation of ultrathin WSe{sub 2} using spectroscopic ellipsometry

    SciTech Connect

    Eichfeld, Sarah M.; Lin, Yu-Chuan; Hossain, Lorraine; Eichfeld, Chad M.; Robinson, Joshua A.

    2014-09-01

    The utilization of tungsten diselenide (WSe{sub 2}) in electronic and optoelectronic devices depends on the ability to understand and control the process-property relationship during synthesis. We demonstrate that spectroscopic ellipsometry is an excellent technique for accurate, non-destructive determination of ultra-thin (<30 nm) WSe{sub 2} properties. The refractive index (n) and extinction coefficient (k) were found to be independent of thickness down to 1.3 nm, and were used to determine film thickness, which was confirmed to be within 9% of values found via atomic force microscopy. Finally, the optical bandgap was found to closely correlate with thickness, ranging from 1.2 to 1.55 eV as the WSe{sub 2} is thinned to the equivalent of 2 atomic layers.

  16. High-resolution thermal imaging methodology for non-destructive evaluation of historic structures

    NASA Astrophysics Data System (ADS)

    Hess, Michael; Vanoni, David; Petrovic, Vid; Kuester, Falko

    2015-11-01

    This paper presents a methodology for automated, portable thermography, for the acquisition of high-resolution thermal image mosaics supporting the non-destructive evaluation of historic structures. The presented approach increases the spatial resolution of thermal surveys to a level of detail needed for building scale analysis. The integration of a robotic camera platform enables automated alignment of multiple images into a high-resolution thermal image mosaic giving a holistic view of the structure while maintaining a level of detail equaling or exceeding that of traditional spot surveys using existing cameras. Providing a digital workflow for automated data and metadata recording increases the consistency and accuracy of surveys regardless of the location or operator. An imaging workflow and instrumentation are shown for a case-study on buildings in Florence, Italy demonstrating the effectiveness of this methodology for structural diagnostics.

  17. Template synthesis of test tube nanoparticles using non-destructive replication.

    PubMed

    Wagner, Jonathan; Yao, Jingyuan; Rodgers, David; Hinds, Bruce

    2013-03-01

    Nano test tubes are a promising delivery vehicle for a range of therapeutics, including small molecule drugs and biologics. However, current template synthesis methods of producing nano test tubes are prohibitively expensive and time consuming. Here, non-destructive template replication was used to increase nano test tube yield from porous alumina by more than a hundredfold. We demonstrate how to produce nano test tubes of several sizes and compositions, including hybrid tubes with different inner and outer surfaces for targeted surface chemistry. Nano test tubes were readily suspended and stored in aqueous solutions without the need for chemical treatment. These nano test tubes should find application as delivery vehicles for therapeutics, particularly for processive 'bionanoreactors' loaded with enzymes.

  18. Non-Destructive Evaluation of Depth of Surface Cracks Using Ultrasonic Frequency Analysis

    PubMed Central

    Her, Shiuh-Chuan; Lin, Sheng-Tung

    2014-01-01

    Ultrasonic is one of the most common uses of a non-destructive evaluation method for crack detection and characterization. The effectiveness of the acoustic-ultrasound Structural Health Monitoring (SHM) technique for the determination of the depth of the surface crack was presented. A method for ultrasonic sizing of surface cracks combined with the time domain and frequency spectrum was adopted. The ultrasonic frequency spectrum was obtained by Fourier transform technique. A series of test specimens with various depths of surface crack ranging from 1 mm to 8 mm was fabricated. The depth of the surface crack was evaluated using the pulse-echo technique. In this work, three different longitudinal waves with frequencies of 2.25 MHz, 5 MHz and 10 MHz were employed to investigate the effect of frequency on the sizing detection of surface cracks. Reasonable accuracies were achieved with measurement errors less than 7%. PMID:25225875

  19. Measurements of aerospace materials and their interpretation for non-destructive testing

    NASA Astrophysics Data System (ADS)

    Salmon, Neil A.; Mason, Ian; Price, Sean; Beale, John

    2009-09-01

    Millimetre and terahertz radiation penetration into materials enables non-destructive testing capabilities for the aerospace industry, either remotely using imaging technology or locally using microscope type diagnostics. This paper presents measurements made on Norcoat and Prosial, used in the aerospace industry for thermal insulation and on carbon fibre, used for its high strength weight ratio. Michelson interferometer measurements over the band 100 GHz to 1 THz, with a 30 GHz spectral resolution, are presented, together with images of a range of samples taken using a 35 GHz real-time imaging system. The measured optical properties of these materials are examined and used in modelling to predict signatures of failure modes in these materials when they are attached to cryogenic fuel tanks.

  20. Non-destructive testing of mid-IR optical fiber using infrared imaging

    NASA Astrophysics Data System (ADS)

    Gagnon, Marc-André; Fortin, Vincent; Vallée, Réal; Farley, Vincent; Lagueux, Philippe; Guyot, Éric; Marcotte, Frédérick

    2016-10-01

    Optical fiber lasers offers the advantage of being relatively compact and efficient. However, the materials such as fluoride and chalcogenide glasses used for their fabrication must be exempt of defects in order to make efficient laser systems. However, most existing quality control techniques are not compatible with chalcogenide fibers because of their limited transparency in the visible spectral range. For this reason, the Université Laval's Centre d'optique, photonique et laser (COPL), in Quebec City, Canada, has developed a novel non-destructive testing (NDT) methodology based on infrared imaging to address this problem. The results show how this simple screening technique eases the selection of high-quality fibers for the design of high-power mid-IR lasers.

  1. Pulsed Eddy Current Non-destructive Testing and Evaluation: A Review

    NASA Astrophysics Data System (ADS)

    Sophian, Ali; Tian, Guiyun; Fan, Mengbao

    2017-05-01

    Pulsed eddy current (PEC) non-destructive testing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the literature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numerically have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT&E are also presented.

  2. Monitoring ground anchor using non-destructive ground anchor integrity test (NDT-GRANIT)

    SciTech Connect

    Robbany, Z. Handayani, G.

    2015-09-30

    Monitoring at ground anchor commonly uses a pull out test method, therefor we developing a non-destructive ground anchor integrity testing (NDT-GRANIT). NDT-GRANIT using the principle of seismic waves that have been modified into form of sweep signal, the signal will be demodulated, filtered, and Fourier transformation (inverse discrete Fourier transform) so the data can be interpreted reflected wave from the ground anchor. The method was applied to determine whether the ground anchor still gripped in the subsurface by looking the attenuation of the wave generated sources. From the result we can see that ground anchor does not grip. To validate the results of the comparison method of measurement used pile integrity test.

  3. Non-destructive detection of water stress and estimation of relative water content in maize

    NASA Astrophysics Data System (ADS)

    Zygielbaum, Arthur I.; Gitelson, Anatoly A.; Arkebauer, Timothy J.; Rundquist, Donald C.

    2009-06-01

    Non-destructive estimation of leaf water content provides vital information about vegetation productivity. We report here on controlled seven day experiments using greenhouse-grown maize. Fifty plants were randomly assigned to two equal groups: water stressed and well watered. Spectroscopic, relative water content (RWC), and chlorophyll concentration measurements were made daily. Because water molecules absorb radiation in near- and middle-infrared, most efforts to sense water deficit remotely utilize infrared wavelengths. In these experiments, we identified a strong, systematic, and repeatable relationship between photosynthetically active radiation (PAR, 400-700 nm) albedo and leaf RWC. We show that visible spectrum reflectance provides a means to detect early stages of plant stress and estimate leaf RWC.

  4. High-speed image processing systems in non-destructive testing

    NASA Astrophysics Data System (ADS)

    Shashev, D. V.; Shidlovskiy, S. V.

    2017-08-01

    Digital imaging systems are using in most of both industrial and scientific industries. Such systems effectively solve a wide range of tasks in the field of non-destructive testing. There are problems in digital image processing for decades associated with the speed of the operation of such systems, sufficient to efficiently process and analyze video streams in real time, ideally in mobile small-sized devices. In this paper, we consider the use of parallel-pipeline computing architectures in image processing problems using the example of an algorithm for calculating the area of an object on a binary image. The approach used allows us to achieve high-speed performance in the tasks of digital image processing.

  5. Wave field features of shallow vertical discontinuity and their application in non-destructive detection

    USGS Publications Warehouse

    Liu, J.; Xia, J.; Luo, Y.; Chen, C.; Li, X.; Huang, Y.

    2007-01-01

    The geotechnical integrity of critical infrastructure can be seriously compromised by the presence of fractures or crevices. Non-destructive techniques to accurately detect fractures in critical infrastructure such as dams and highways could be of significant benefit to the geotechnical industry. This paper investigates the application of shallow seismic and georadar methods to the detection of a vertical discontinuity using numerical simulations. The objective is to address the kinematical analysis of a vertical discontinuity, determine the resulting wave field characteristics, and provide the basis for determining the existence of vertical discontinuities based on the recorded signals. Simulation results demonstrate that: (1) A reflection from a vertical discontinuity produces a hyperbolic feature on a seismic or georadar profile; (2) In order for a reflection from a vertical discontinuity to be produced, a reflecting horizon below the discontinuity must exist, the offset between source and receiver (x0) must be non-zero, on the same side of the vertical discontinuity; (3) The range of distances from the vertical discontinuity where a reflection event is observed is proportional to its length and to x0; (4) Should the vertical crevice (or fracture) pass through a reflecting horizon, dual hyperbolic features can be observed on the records, and this can be used as a determining factor that the vertical crevice passes through the interface; and (5) diffractions from the edges of the discontinuity can be recorded with relatively smaller amplitude than reflections and their ranges are not constrained by the length of discontinuity. If the length of discontinuity is short enough, diffractions are the dominant feature. Real-world examples show that the shallow seismic reflection method and the georadar method are capable of recording the hyperbolic feature, which can be interpreted as vertical discontinuity. Thus, these methods show some promise as effective non-destructive

  6. Non-destructive ripeness sensing by using proton NMR (Nuclear Magnetic Resonance)

    SciTech Connect

    Cho, Seong In; Krutz, G.W.; Stroshine, R.L. . Dept. of Agricultural Engineering); Bellon, V. , 34 - Montpellier )

    1990-01-01

    More than 80 kinds of fruits and vegetables are available in the United States. But only about 6 of them have their quality standards (Dull, 1986). In the 1990 Fresh Trends survey (Zind, 1990), consumers were asked to rate 16 characteristics important to their decision to purchase fresh produce. The four top ranking factors were ripeness/freshness, taste/flavor, appearance/condition and nutritional value. Of these surveyed, 96% rated ripeness/freshness as extremely important or very important. Therefore, the development of reliable grading or sorting techniques for fresh commodities is essential. Determination of fruit quality often involves cutting and tasting. Non-destructive quality control in fruit and vegetables is a goal of growers and distributors, as well as the food processing industry. Many nondestructive techniques have been evaluated including soft x-ray, optical transmission, near infrared radiation, and machine vision. However, there are few reports of successful non-destructive measurement of sugar content directly in fruit. Higher quality fruit could be harvested and available to consumers if a nondestructive sensor that detects ripeness level directly by measuring sugar content were available. Using proton Nuclear Magnetic Resonance (NMR) principle is the possibility. A nondestructive ripeness (or sweetness) sensor for fruit quality control can be developed with the proton NMR principle (Cho, 1989). Several feasibility studies were necessary for the ripeness sensor development. Main objectives in this paper was to investigate the feasibilities (1) to detect ripeness (or sweetness level) of raw fruit tissue with an high resolution proton NMR spectroscopy (200 MHz) and (2) to measure sugar content of intact fruit with a low resolution proton NMR spectroscopy (10 MHz). 7 refs., 4 figs.

  7. Non-destructive Ripeness Sensing by Using Proton NMR [Nuclear Magnetic Resonance

    DOE R&D Accomplishments Database

    Cho, Seong In; Krutz, G. W.; Stroshine, R. L.; Bellon, V.

    1990-01-01

    More than 80 kinds of fruits and vegetables are available in the United States. But only about 6 of them have their quality standards (Dull, 1986). In the 1990 Fresh Trends survey (Zind, 1990), consumers were asked to rate 16 characteristics important to their decision to purchase fresh produce. The four top ranking factors were ripeness/freshness, taste/flavor, appearance/condition and nutritional value. Of these surveyed, 96% rated ripeness/freshness as extremely important or very important. Therefore, the development of reliable grading or sorting techniques for fresh commodities is essential. Determination of fruit quality often involves cutting and tasting. Non-destructive quality control in fruit and vegetables is a goal of growers and distributors, as well as the food processing industry. Many nondestructive techniques have been evaluated including soft x-ray, optical transmission, near infrared radiation, and machine vision. However, there are few reports of successful non-destructive measurement of sugar content directly in fruit. Higher quality fruit could be harvested and available to consumers if a nondestructive sensor that detects ripeness level directly by measuring sugar content were available. Using proton Nuclear Magnetic Resonance (NMR) principle is the possibility. A nondestructive ripeness (or sweetness) sensor for fruit quality control can be developed with the proton NMR principle (Cho, 1989). Several feasibility studies were necessary for the ripeness sensor development. Main objectives in this paper was to investigate the feasibilities (1) to detect ripeness (or sweetness level) of raw fruit tissue with an high resolution proton NMR spectroscopy (200 MHz) and (2) to measure sugar content of intact fruit with a low resolution proton NMR spectroscopy (10 MHz).

  8. Magnetic Microcalorimeter Gamma Detectors for High-Precision Non-Destructive Analysis

    SciTech Connect

    Friedrich, Stephan; Bates, Cameron; Pereverzev, Sergey

    2014-10-03

    Cryogenic gamma (γ) detectors with operating temperatures of ~0.1 K offer 10× better energy resolution than conventional high-purity germanium detectors that are currently used for non-destructive analysis (NDA) of nuclear materials. This can greatly increase the accuracy of NDA, especially at low-energies where gamma rays often have similar energies and cannot be resolved by Ge detectors. Among the different cryogenic detector types, Magnetic Micro-Calorimeters (MMCs) have the potential of faster count rates and better linearity. High linearity is essential to add spectra from different pixels in detector arrays that are needed for high sensitivity. MMC gamma detectors measure the energy of absorbed gamma rays form the resulting change in magnetization of an erbium-doped gold (Au:Er) sensor. The signal is read out with a SQUID preamplifier and processed digitally with room temperature electronics (see inset figure 2). The objective of this project is to develop ultra-high energy resolution γ-detectors based on magnetic micro-calorimeters (MMCs) for accurate non-destructive isotope analysis (NDA). Since MMCs, like other cryogenic γ-detector technologies with operating temperatures <0.1 K, are intrinsically slow and have to be small for high resolution, special emphasis will be placed on questions that determine sensitivity and the potential for scaling to arrays. Objectives for FY14 were therefore to fabricate an improved version of MMC γ-detectors and test their energy resolution, maximum count rate, readout noise, crosstalk between pixels and linearity.

  9. Non-destructive in situ mapping of macroholes, cracks and inhomogeneities of stalagmites in cave environments

    NASA Astrophysics Data System (ADS)

    Hegymegi, Erika; Gyöngy, Miklós; Bodolai, Tamás; Divós, Ferenc; Barta, Edit; Gribovszki, Katalin; Bokelmann, Götz; Hegymegi, Csaba; Lednická, Markéta; Kovács, Károly

    2016-04-01

    Intact and vulnerable, candle-stick type stalagmites can be used as prehistoric-earthquake indicators during seismic-hazard analysis of a given region, because they are old enough to survive several earthquakes. The continued intactness of the stalagmites indicates a lack of earthquakes that had the strength to destroy them. To make sure that the stalagmites are intact, we have to image their internal structure in order to estimate the steadiness more accurate and potential failure in the last few thousand years, during their evolution. These stalagmites play an important indicator role and carry fundamental information; however, legally they are strictly protected natural objects in Europe. Therefore it is impossible to examine them in the laboratory by conventional equipment such as computer tomography (CT) or X-ray, because this would require taking samples. With the presented non-destructive methods (ultrasound and acoustic tomography) we tried to detect macroholes, cracks and velocity anomalies inside the stalagmites on the mm scale in situ, in the cave. The acoustic tomography applied in the current work is an existing method in forest research. Forest researchers use it to non-destructively detect the size and location of decayed or hollow parts in the trunk and this technique is able to detect the velocity changing of wave propagation and anomalies in the stalagmites as well. The other method that we use is ultrasound imaging, which uses (and is able to calculate) the velocity of sound propagation. Here, the frequency used is much higher (typically 250 kHz to 5 MHz), which increases resolution but at the same time decreases penetration depth compared to acoustic tomography. In this latter work, through transmission and TOFD (time-of-flight-diffraction) ultrasound methods are using thickness-mode ultrasound transducers (Panametrics, Olympus). Such equipment is well-adapted to the cave environment and this is the first time that it has been used for these

  10. Monitoring fungal growth on brown rice grains using rapid and non-destructive hyperspectral imaging.

    PubMed

    Siripatrawan, U; Makino, Y

    2015-04-16

    This research aimed to develop a rapid, non-destructive, and accurate method based on hyperspectral imaging (HSI) for monitoring spoilage fungal growth on stored brown rice. Brown rice was inoculated with a non-pathogenic strain of Aspergillus oryzae and stored at 30 °C and 85% RH. Growth of A. oryzae on rice was monitored using viable colony counts, expressed as colony forming units per gram (CFU/g). The fungal development was observed using scanning electron microscopy. The HSI system was used to acquire reflectance images of the samples covering the visible and near-infrared (NIR) wavelength range of 400-1000 nm. Unsupervised self-organizing map (SOM) was used to visualize data classification of different levels of fungal infection. Partial least squares (PLS) regression was used to predict fungal growth on rice grains from the HSI reflectance spectra. The HSI spectral signals decreased with increasing colony counts, while conserving similar spectral pattern during the fungal growth. When integrated with SOM, the proposed HSI method could be used to classify rice samples with different levels of fungal infection without sample manipulation. Moreover, HSI was able to rapidly identify infected rice although the samples showed no symptoms of fungal infection. Based on PLS regression, the coefficient of determination was 0.97 and root mean square error of prediction was 0.39 log (CFU/g), demonstrating that the HSI technique was effective for prediction of fungal infection in rice grains. The ability of HSI to detect fungal infection at early stage would help to prevent contaminated rice grains from entering the food chain. This research provides scientific information on the rapid, non-destructive, and effective fungal detection system for rice grains. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Portable 1,5 MeV X-Band Linac For Non-destructive Radiography

    NASA Astrophysics Data System (ADS)

    Saversky, A. J.; Rodionov, A. E.; Shaltyrev, A. P.; Shchedrin, I. S.

    1997-05-01

    Portable linear electron accelerator Y-34 developed in Small Accelerator Laboratory of MEPhI for non-destructive industrial radiography. This Linac is a fully self-contained device with the exception of external electric power 220Vx50Gz, 1 phase, 5 kVA. Full mass of Linac Y-34 - less than 300 kg. The Radiographic parameters: Nominal Energy - 1,5 MeV; Energy Range - 0,7...1,8 MeV; Maximum pulse current - 100 mA; Maximum Intensity - 15 R/min@m; Focal spot size - less than 2 mm. The Linac is comprised of 4 subassemblies. The X-ray head with weight less than 100 kg, dimensions: 0,7x0,7x1,0 m contains the traveling-wave accelerating structure with lens 0,4 m, electron gun, vacuum pump, tungsten target and RF-system with 500-kW magnetron. The permanent magnets focusing system provides focal spot less than 2 mm. The high voltage power unit consist of a line-type magnetron/electron gun modulator 2 kW power supply, the weight is equal 70 kg. The self-contained cooling water supply provides temperature controlled water for accelerator structure and magnetron. The control console allows convenient monitoring of critical system and Linac parameters by manual or remote computer. Portable X-band Linac Y-34 is the effective X - ray and/or electron beam source for such applications as non-destructive examination of nuclear reactor systems, solid rocket motors, technology research.

  12. Variation in gymnemic acid content and non-destructive harvesting of Gymnema sylvestre (Gudmar)

    PubMed Central

    Pandey, Ashok Kumar; Yadav, Swati

    2010-01-01

    Background: Madhunashini (Gymnema sylvestre R. Br.) commonly known as ‘Gudmar’ in Hindi is an important medicinal climber and extensively used in almost all Indian System of Medicine as a remedy for diabetes, rheumatism, cough, ulcer, jaundice, dyspepsia, constipation, eyes pain and also in snakebite. In India, it is found growing in Andhra Pradesh, Bihar, Chhattisgarh, Karnataka, Kerala, Madhya Pradesh, Maharastra, Orissa, Tamil Nadu, Uttar Pradesh and West Bengal. The major phytoconstituents are gymnemic acids, gudmarin and saponins. Methods: In the present study, Gymnema germplasm collected from various regions of Madhya Pradesh was evaluated on the basis of their morphological characteristics and gymnemic acid content. Gymnemic acid content in the leaves was estimated by HPLC. We have also standardized the non-destructive harvesting practices of Gudmar. Selective harvesting was done without harming the main plant. Only mature leaves (60%) were hand plucked in the month of October. Second harvest was done in the month of June. Results: Data revealed that gymnemic acid content varied between 0.96% ± 0.03 (Seoni) to 1.58% ±0.03 (Amarkantak). It was also observed that the leaves left at the time of 1st harvest during October matured in June at the time of 2nd harvest. Conclusion: Non destructive harvesting practice did not have any negative impact on overall development of the plant. It is evident that there is wide variation in the morphological characteristics and gymnemic acid content in G. sylvestre collected from various locations, which can be exploited for further crop improvement programmes. PMID:21589758

  13. A Monte Carlo approach applied to ultrasonic non-destructive testing

    NASA Astrophysics Data System (ADS)

    Mosca, I.; Bilgili, F.; Meier, T. M.; Sigloch, K.

    2011-12-01

    Non-destructive testing based on ultrasound allows us to detect, characterize and size discrete flaws in geotechnical and engineering structures and materials. This information is needed to determine whether such flaws can be tolerated in future service. In typical ultrasonic experiments, only the first-arriving P-wave is interpreted, and the remainder of the recorded waveform is neglected. Our work aims at understanding surface waves, which are strong signals in the later wave train, with the ultimate goal of full waveform tomography. At present, even the structural estimation of layered media is still challenging because material properties of the samples can vary widely, and good initial models for inversion do not often exist. The aim of the present study is to analyze ultrasonic waveforms measured at the surface of Plexiglas and rock samples, and to define the behaviour of surface waves in structures of increasing complexity. The tremendous potential of ultrasonic surface waves becomes an advantage only if numerical forward modelling tools are available to describe the waveforms accurately. We compute synthetic full seismograms as well as group and phase velocities for the data. We invert them for the elastic properties of the sample via a global search of the parameter space, using the Neighbourhood Algorithm. Such a Monte Carlo approach allows us to perform a complete uncertainty and resolution analysis, but the computational cost is high and increases quickly with the number of model parameters. Therefore it is practical only for defining the seismic properties of media with a limited number of degrees of freedom, such as layered structures. We have applied this approach to both synthetic layered structures and real samples. The former contributed to benchmark the propagation of ultrasonic surface waves in typical materials tested with a non-destructive technique (e.g., marble, unweathered and weathered concrete and natural stone).

  14. Morphomechanics of dermis-A method for non-destructive testing of collagenous tissues.

    PubMed

    Shah, R G; Pierce, M C; Silver, F H

    2017-08-01

    Collagenous tissues store, transmit and dissipate elastic energy during mechanical deformation. In skin, mechanical energy is stored during loading and then is dissipated, which protects skin from mechanical failure. Thus, energy storage (elastic properties) and dissipation (viscous properties) are important characteristics of extracellular matrices (ECMs) that support the cyclic loading of ECMs without tissue failure. Uniaxial stress-strain measurements on decellularized human dermis have been made and compared to results of a non-destructive technique involving optical coherence tomography (OCT) combined with vibrational analysis. In addition, Poisson's ratio has been determined for tensile deformation of decellularized dermis. The modulus of decellularized dermis measured using standard tensile stress-strain tests and that determined from calculations derived from natural frequency measurements give similar results. It is also observed that Poisson's ratio for dermis is between 0.38 and 0.63 after correction for changes in volume that occur during tensile deformation. These results suggest that the assumption that dermis and other ECMs deform at constant volume is incorrect and will lead to differences in the calculated modulus by conventional tensile stress-strain measurements. It is proposed that OCT in conjunction with vibrational analysis is a convenient way to non-destructively measure the modulus of decellularized dermis, ECMs and other materials that have a positive curvature to their stress-strain curves. Tensile deformation of dermis and possibly other ECMs is associated with an increase in Poisson's ratio consistent with a model of fluid expulsion from collagen fibrils during stretching. The value of Poisson's ratio should be considered in analyzing the mechanical properties of ECMs since at least dermis appears to be compressible during tensile deformation. Fluid expression during tensile deformation may play a role in mechanotransduction in skin in a

  15. Health and Household Air Pollution from Solid Fuel Use: The Need for Improved Exposure Assessment

    PubMed Central

    Peel, Jennifer L.; Balakrishnan, Kalpana; Breysse, Patrick N.; Chillrud, Steven N.; Naeher, Luke P.; Rodes, Charles E.; Vette, Alan F.; Balbus, John M.

    2013-01-01

    Background: Nearly 3 billion people worldwide rely on solid fuel combustion to meet basic household energy needs. The resulting exposure to air pollution causes an estimated 4.5% of the global burden of disease. Large variability and a lack of resources for research and development have resulted in highly uncertain exposure estimates. Objective: We sought to identify research priorities for exposure assessment that will more accurately and precisely define exposure–response relationships of household air pollution necessary to inform future cleaner-burning cookstove dissemination programs. Data Sources: As part of an international workshop in May 2011, an expert group characterized the state of the science and developed recommendations for exposure assessment of household air pollution. Synthesis: The following priority research areas were identified to explain variability and reduce uncertainty of household air pollution exposure measurements: improved characterization of spatial and temporal variability for studies examining both short- and long-term health effects; development and validation of measurement technology and approaches to conduct complex exposure assessments in resource-limited settings with a large range of pollutant concentrations; and development and validation of biomarkers for estimating dose. Addressing these priority research areas, which will inherently require an increased allocation of resources for cookstove research, will lead to better characterization of exposure–response relationships. Conclusions: Although the type and extent of exposure assessment will necessarily depend on the goal and design of the cookstove study, without improved understanding of exposure–response relationships, the level of air pollution reduction necessary to meet the health targets of cookstove interventions will remain uncertain. Citation: Clark ML, Peel JL, Balakrishnan K, Breysse PN, Chillrud SN, Naeher LP, Rodes CE, Vette AF, Balbus JM. 2013. Health

  16. Association between pregnancy exposure to air pollution and birth weight in selected areas of Norway.

    PubMed

    Panasevich, Sviatlana; Håberg, Siri Eldevik; Aamodt, Geir; London, Stephanie J; Stigum, Hein; Nystad, Wenche; Nafstad, Per

    2016-01-01

    Exposure to air pollution has adverse effects on cardiopulmonary health of adults. Exposure to air pollution in pregnancy may affect foetal development. However, the evidence of such effect remains inconsistent. We investigated the effects of exposure to air pollution during pregnancy on birth outcomes. This study, based within the Norwegian Mother and Child Cohort Study (MoBa), includes 17,533 participants living in the two largest cities in Norway: Oslo and Bergen, and their two surrounding counties: Akershus and Hordaland. Air pollution levels at residential addresses were estimated using land use regression models and back-extrapolated to the period of each pregnancy using continuous monitoring station data. Birth outcomes were birth weight, low birth weight, gestational age, and preterm delivery obtained from the Medical Birth Registry of Norway. Information on lifestyle factors was collected from MoBa questionnaires completed by mothers during pregnancy. Linear and logistic regression models were used to analyse the associations between pregnancy NO2 exposure and birth outcomes. We found a statistically significant negative association between pregnancy exposure to NO2 and birth weight -43.6 (95%CI -55.8 to -31.5) g per 10 μg/m(3) NO2. However, after adjusting for either area or the combination of parity and maternal weight, no substantive effects of air pollution exposure were evident. Exposure to air pollution during pregnancy was associated with decrease in birth weight, but area-related and lifestyle factors attenuated this association. We found no statistically significant associations of air pollution exposure with gestational age, low birth weight or preterm delivery.

  17. Susceptibility Factors Relevant for the Association Between Long-Term Air Pollution Exposure and Incident Asthma.

    PubMed

    Burte, Emilie; Nadif, Rachel; Jacquemin, Bénédicte

    2016-03-01

    In this review, we identified 15 studies in children and 10 studies in adults that assessed the association between long-term exposure to air pollution and incident asthma and that conducted stratified analyses to explore potential susceptibility factors. Overall, adult never-/former smokers seem to be at higher risk of incident asthma due to air pollution. Children without atopy and children from low socioeconomic status families also seem to be at higher risk of incident asthma due to air pollution. While interaction between air pollution and genes involved in the response to oxidative stress pathways have been explored, results are somewhat inconsistent and in need of replication. To evaluate interactions, large sample sizes are necessary, and much more research, including data pooling from existing studies, is needed to further explore susceptibility factors for asthma incidence due to long-term air pollution exposure.

  18. Air pollution impacts on avian species via inhalation exposure and associated outcomes

    NASA Astrophysics Data System (ADS)

    Sanderfoot, Olivia V.; Holloway, Tracey

    2017-08-01

    Despite the well-established links between air pollution and human health, vegetation, and aquatic ecosystems, less attention has been paid to the potential impact of reactive atmospheric gases and aerosols on avian species. In this literature review, we summarize findings published since 1950 regarding avian responses to air pollution and discuss knowledge gaps that could be addressed in future studies. We find consistent evidence for adverse health impacts on birds attributable to exposure to gas-phase and particulate air pollutants, including carbon monoxide (CO), ozone (O3), sulfur dioxide (SO2), smoke, and heavy metals, as well as mixtures of urban and industrial emissions. Avian responses to air pollution include respiratory distress and illness, increased detoxification effort, elevated stress levels, immunosuppression, behavioral changes, and impaired reproductive success. Exposure to air pollution may furthermore reduce population density, species diversity, and species richness in bird communities.

  19. Ambient air pollution exposure and the incidence of related health effects among racial/ethnic minorities

    SciTech Connect

    Nieves, L.A.; Wernette, D.R.

    1997-02-01

    Differences among racial and ethnic groups in morbidity and mortality rates for diseases, including diseases with environmental causes, have been extensively documented. However, documenting the linkages between environmental contaminants, individual exposures, and disease incidence has been hindered by difficulties in measuring exposure for the population in general and for minority populations in particular. After briefly discussing research findings on associations of common air pollutants with disease incidence, the authors summarize recent studies of radial/ethnic subgroup differences in incidence of these diseases in the US. They then present evidence of both historic and current patterns of disproportionate minority group exposure to air pollution as measured by residence in areas where ambient air quality standards are violated. The current indications of disproportionate potential exposures of minority and low-income populations to air pollutants represent the continuation of a historical trend. The evidence of linkage between disproportionate exposure to air pollution of racial/ethnic minorities and low-income groups and their higher rates of some air pollution-related diseases is largely circumstantial. Differences in disease incidence and mortality rates among racial/ethnic groups are discussed for respiratory diseases, cancers, and lead poisoning. Pollutants of concern include CO, Pb, SO{sub 2}, O{sub 3}, and particulates.

  20. Short-Term Exposure to Air Pollution and Digital Vascular Function

    PubMed Central

    Ljungman, Petter L.; Wilker, Elissa H.; Rice, Mary B.; Schwartz, Joel; Gold, Diane R.; Koutrakis, Petros; Vita, Joseph A.; Mitchell, Gary F.; Vasan, Ramachandran S.; Benjamin, Emelia J.; Mittleman, Murray A.; Hamburg, Naomi M.

    2014-01-01

    We investigated associations between ambient air pollution and microvessel function measured by peripheral arterial tonometry between 2003 and 2008 in the Framingham Heart Study Offspring and Third Generation Cohorts. We measured particulate matter with aerodynamic diameter ≤2.5 µm (PM2.5), black carbon, sulfates, particle number, nitrogen oxides, and ozone by using fixed monitors, and we determined moving averages for 1–7 days preceding vascular testing. We examined associations between these exposures and hyperemic response to ischemia and baseline pulse amplitude, a measure of arterial tone (n = 2,369). Higher short-term exposure to air pollutants, including PM2.5, black carbon, and particle number was associated with higher baseline pulse amplitude. For example, higher 3-day average PM2.5 exposure was associated with 6.3% higher baseline pulse amplitude (95% confidence interval: 2.0, 10.9). However, there were no consistent associations between the air pollution exposures assessed and hyperemic response. Our findings in a community-based sample exposed to relatively low pollution levels suggest that short-term exposure to ambient particulate pollution is not associated with vasodilator response, but that particulate air pollution is associated with baseline pulse amplitude, suggesting potentially adverse alterations in baseline vascular tone or compliance. PMID:25100647

  1. Evaluation of air-liquid interface exposure systems for in vitro assessment of airborne pollutants

    EPA Science Inventory

    Exposure of cells to airborne pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of submerged cells. The published literature, however, describes irreproducible and/or unrealistic experimental conditions using ALI systems. We have compared fi...

  2. (CZ)BIOMARKERS OF EXPOSURE TO PARTICULATE AIR POLLUTION IN THE CZECH REPUBLIC

    EPA Science Inventory

    The use of biomarkers in the Teplice Program, provided a key tool to relate health outcomes to individual personal exposures and to provide measures of confounding exposures. This research program on the health effects of air pollution studied a population living in the heavil...

  3. (PRAGUE)BIOMARKERS OF EXPOSURE TO PARTICULATE AIR POLLUTION IN THE CZECH REPUBLIC

    EPA Science Inventory

    The use of biomarkers in the Teplice Program, provided a key tool to relate health outcomes to individual personal exposures and to provide measures of confounding exposures. This research program on the health effects of air pollution studied a population living in the heavil...

  4. Critical Evaluation of Air-Liquid Interface Exposure Devices for In Vitro Assessment of Atmospheric Pollutants

    EPA Science Inventory

    Exposure of cells to atmospheric pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of attached cells submerged in liquid medium. However, there is still limited understanding of the ideal ALI device design features that permit reproducible a...

  5. (CZ)BIOMARKERS OF EXPOSURE TO PARTICULATE AIR POLLUTION IN THE CZECH REPUBLIC

    EPA Science Inventory

    The use of biomarkers in the Teplice Program, provided a key tool to relate health outcomes to individual personal exposures and to provide measures of confounding exposures. This research program on the health effects of air pollution studied a population living in the heavil...

  6. (PRAGUE)BIOMARKERS OF EXPOSURE TO PARTICULATE AIR POLLUTION IN THE CZECH REPUBLIC

    EPA Science Inventory

    The use of biomarkers in the Teplice Program, provided a key tool to relate health outcomes to individual personal exposures and to provide measures of confounding exposures. This research program on the health effects of air pollution studied a population living in the heavil...

  7. Effect of geocoding errors on traffic-related air pollutant exposure and concentration estimates

    EPA Science Inventory

    Exposure to traffic-related air pollutants is highest very near roads, and thus exposure estimates are sensitive to positional errors. This study evaluates positional and PM2.5 concentration errors that result from the use of automated geocoding methods and from linearized approx...

  8. Critical Evaluation of Air-Liquid Interface Exposure Devices for In Vitro Assessment of Atmospheric Pollutants

    EPA Science Inventory

    Exposure of cells to atmospheric pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of attached cells submerged in liquid medium. However, there is still limited understanding of the ideal ALI device design features that permit reproducible a...

  9. Evaluation of air-liquid interface exposure systems for in vitro assessment of airborne pollutants

    EPA Science Inventory

    Exposure of cells to airborne pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of submerged cells. The published literature, however, describes irreproducible and/or unrealistic experimental conditions using ALI systems. We have compared fi...

  10. Effect of geocoding errors on traffic-related air pollutant exposure and concentration estimates

    EPA Science Inventory

    Exposure to traffic-related air pollutants is highest very near roads, and thus exposure estimates are sensitive to positional errors. This study evaluates positional and PM2.5 concentration errors that result from the use of automated geocoding methods and from linearized approx...

  11. CONCENTRATION - DURATION RELATIONSHIPS FOR NON-CANCER HEALTH EFFECTS OF EXPOSURE TO HAZARDOUS AIR POLLUTANTS.

    EPA Science Inventory

    EPA is charged with assessing the risks of both acute and chronic exposures to hazardous air pollutants
    (HAPs). The emissions from sources of HAPs are often characterized as temporally-averaged values,
    however, patterns of exposure not captured in such measures may infl...

  12. Long-term exposure to air pollution and cardiorespiratory disease in the California teachers study cohort.

    PubMed

    Lipsett, Michael J; Ostro, Bart D; Reynolds, Peggy; Goldberg, Debbie; Hertz, Andrew; Jerrett, Michael; Smith, Daniel F; Garcia, Cynthia; Chang, Ellen T; Bernstein, Leslie

    2011-10-01

    Several studies have linked long-term exposure to particulate air pollution with increased cardiopulmonary mortality; only two have also examined incident circulatory disease. To examine associations of individualized long-term exposures to particulate and gaseous air pollution with incident myocardial infarction and stroke, as well as all-cause and cause specific mortality. We estimated long-term residential air pollution exposure for more than 100,000 participants in the California Teachers Study, a prospective cohort of female public school professionals.We linked geocoded residential addresses with inverse distance-weighted monthly pollutant surfaces for two measures of particulate matter and for several gaseous pollutants. We examined associations between exposure to these pollutants and risks of incident myocardial infarction and stroke, and of all-cause and cause-specific mortality, using Cox proportional hazards models. We found elevated hazard ratios linking long-term exposure to particulate matter less than 2.5 μm in aerodynamic diameter (PM2.5), scaled to an increment of 10 μg/m3 with mortality from ischemic heart disease (IHD) (1.20; 95% confidence interval [CI], 1.02-1.41) and, particularly among postmenopausal women, incident stroke (1.19; 95% CI, 1.02-1.38). Long-term exposure to particulate matter less than 10 μm in aerodynamic diameter (PM10) was associated with elevated risks for IHD mortality (1.06; 95% CI, 0.99-1.14) and incident stroke (1.06; 95% CI, 1.00-1.13), while exposure to nitrogen oxides was associated with elevated risks for IHD and all cardiovascular mortality. This study provides evidence linking long-term exposure to PM2.5 and PM10 with increased risks of incident stroke as well as IHD mortality; exposure to nitrogen oxides was also related to death from cardiovascular diseases.

  13. A novel approach for exposure assessment in air pollution epidemiological studies using neuro-fuzzy inference systems: Comparison of exposure estimates and exposure-health associations.

    PubMed

    Blanes-Vidal, Victoria; Cantuaria, Manuella Lech; Nadimi, Esmaeil S

    2017-04-01

    Many epidemiological studies have used proximity to sources as air pollution exposure assessment method. However, proximity measures are not generally good surrogates because of their complex non-linear relationship with exposures. Neuro-fuzzy inference systems (NFIS) can be used to map complex non-linear systems, but its usefulness in exposure assessment has not been extensively explored. We present a novel approach for exposure assessment using NFIS, where the inputs of the model were easily-obtainable proximity measures, and the output was residential exposure to an air pollutant. We applied it to a case-study on NH3 pollution, and compared health effects and exposures estimated from NFIS, with those obtained from emission-dispersion models, and linear and non-linear regression proximity models, using 10-fold cross validation. The agreement between emission-dispersion and NFIS exposures was high (Root-mean-square error (RMSE) =0.275, correlation coefficient (r)=0.91) and resulted in similar health effect estimates. Linear models showed poor performance (RMSE=0.527, r=0.59), while non-linear regression models resulted in heterocedasticity, non-normality and clustered data. NFIS could be a useful tool for estimating individual air pollution exposures in epidemiological studies on large populations, when emission-dispersion data are not available. The tradeoff between simplicity and accuracy needs to be considered. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. The microenvironmental modelling approach to assess children's exposure to air pollution - A review.

    PubMed

    Branco, P T B S; Alvim-Ferraz, M C M; Martins, F G; Sousa, S I V

    2014-11-01

    Exposures to a wide spectrum of air pollutants were associated to several effects on children's health. Exposure assessment can be used to establish where and how air pollutants' exposures occur. However, a realistic estimation of children's exposures to air pollution is usually a great ethics challenge, especially for young children, because they cannot intentionally be exposed to contaminants and according to Helsinki declaration, they are not old enough to make a decision on their participation. Additionally, using adult surrogates introduces bias, since time-space-activity patterns are different from those of children. From all the different available approaches for exposure assessment, the microenvironmental (ME) modelling (indirect approach, where personal exposures are estimated or predicted from microenvironment measurements combined with time-activity data) seemed to be the best to assess children's exposure to air pollution as it takes into account the varying levels of pollution to which an individual is exposed during the course of the day, it is faster and less expensive. Thus, this review aimed to explore the use of the ME modelling approach methodology to assess children's exposure to air pollution. To meet this goal, a total of 152 articles, published since 2002, were identified and titles and abstracts were scanned for relevance. After exclusions, 26 articles were fully reviewed and main characteristics were detailed, namely: (i) study design and outcomes, including location, study population, calendar time, pollutants analysed and purpose; and (ii) data collection, including time-activity patterns (methods of collection, record time and key elements) and pollution measurements (microenvironments, methods of collection and duration and time resolution). The reviewed studies were from different parts of the world, confirming the worldwide application, and mostly cross-sectional. Longitudinal studies were also found enhancing the applicability of

  15. Pre-processing of data coming from a laser-EMAT system for non-destructive testing of steel slabs.

    PubMed

    Sgarbi, Mirko; Colla, Valentina; Cateni, Sivia; Higson, Stuart

    2012-01-01

    Non destructive test systems are increasingly applied in the industrial context for their strong potentialities in improving and standardizing quality control. Especially in the intermediate manufacturing stages, early detection of defects on semi-finished products allow their direction towards later production processes according to their quality, with consequent considerable savings in time, energy, materials and work. However, the raw data coming from non destructive test systems are not always immediately suitable for sophisticated defect detection algorithms, due to noise and disturbances which are unavoidable, especially in harsh operating conditions, such as the ones which are typical of the steelmaking cycle. The paper describes some pre-processing operations which are required in order to exploit the data coming from a non destructive test system. Such a system is based on the joint exploitation of Laser and Electro-Magnetic Acoustic Transducer technologies and is applied to the detection of surface and sub-surface cracks in cold and hot steel slabs.

  16. In situ non-destructive measurement of biofilm thickness and topology in an interferometric optical microscope

    SciTech Connect

    Larimer, Curtis; Suter, Jonathan D.; Bonheyo, George; Addleman, Raymond Shane

    2016-03-15

    Biofilms are ubiquitous and deleteriously impact a wide range of industrial processes, medical and dental health issues, and environmental problems such as transport of invasive species and the fuel efficiency of ocean going vessels. Biofilms are difficult to characterize when fully hydrated, especially in a non-destructive manner, because of their soft structure and water-like bulk properties. Herein we describe a non-destructive high resolution method of measuring and monitoring the thickness and topology of live biofilms of using white light interferometric optical microscopy. Using this technique, surface morphology, surface roughness, and biofilm thickness can be measured non-destructively and with high resolution as a function of time without disruption of the biofilm activity and processes. The thickness and surface topology of a P. putida biofilm were monitored growing from initial colonization to a mature biofilm. Typical bacterial growth curves were observed. Increase in surface roughness was a leading indicator of biofilm growth.

  17. Statistical Approaches to Address Multi-Pollutant Mixtures and Multiple Exposures: the State of the Science.

    PubMed

    Stafoggia, Massimo; Breitner, Susanne; Hampel, Regina; Basagaña, Xavier

    2017-10-07

    The purpose of this review is to describe the most recent statistical approaches to estimate the effect of multi-pollutant mixtures or multiple correlated exposures on human health. The health effects of environmental chemicals or air pollutants have been widely described. Often, there exists a complex mixture of different substances, potentially highly correlated with each other and with other (environmental) stressors. Single-exposure approaches do not allow disentangling effects of individual factors and fail to detect potential interactions between exposures. In the last years, sophisticated methods have been developed to investigate the joint or independent health effects of multi-pollutant mixtures or multiple environmental exposures. A classification of the most recent methods is proposed. A non-technical description of each method is provided, together with epidemiological applications and operational details for implementation with standard software.

  18. A simulation study to determine the attenuation and bias in health risk estimates due to exposure measurement error in bi-pollutant models

    EPA Science Inventory

    To understand the combined health effects of exposure to ambient air pollutant mixtures, it is becoming more common to include multiple pollutants in epidemiologic models. However, the complex spatial and temporal pattern of ambient pollutant concentrations and related exposures ...

  19. A simulation study to determine the attenuation and bias in health risk estimates due to exposure measurement error in bi-pollutant models

    EPA Science Inventory

    To understand the combined health effects of exposure to ambient air pollutant mixtures, it is becoming more common to include multiple pollutants in epidemiologic models. However, the complex spatial and temporal pattern of ambient pollutant concentrations and related exposures ...

  20. Ambient air pollution exposure, residential mobility and term birth weight in Oslo, Norway.

    PubMed

    Madsen, Christian; Gehring, Ulrike; Walker, Sam Erik; Brunekreef, Bert; Stigum, Hein; Naess, Oyvind; Nafstad, Per

    2010-05-01

    Environmental exposure during pregnancy may have lifelong health consequences for the offspring and some studies have association between maternal exposure to air pollution during pregnancy and offspring's birth weight. However, many of these studies do not take into account small-scale variations in exposure, residential mobility, and work addresses during pregnancy. We used information from the National Birth Registry of Norway to examine associations between ambient environmental exposure such as air pollution and temperature, and offspring's birth weight taking advantage of information on migration history and work address in a large population-based cohort. A dispersion model was used to estimate ambient air pollution levels at all residential addresses and work addresses for a total of 25,229 pregnancies between 1999 and 2002 in Oslo, Norway. Ambient exposure to traffic pollution for the entire pregnancy was associated with a reduction in term birth weight in crude analyzes when comparing children of the highest and lowest exposed mothers. No evidence for an association between exposure to traffic pollution at home and work addresses and term birth weight after adjustment for covariates known to influence birth weight during pregnancy. After stratification, small statistically non-significant reductions were present but only for multiparious mothers. This group also had less residential mobility and less employment during pregnancy. The overall findings suggest no clear association between term birth weight and traffic pollution exposure during pregnancy. However, mobility patterns could introduce possible confounding when examining small-scale variations in exposure by using addresses. This could be of importance in future studies.

  1. Exposure to outdoor air pollution during trimesters of pregnancy and childhood asthma, allergic rhinitis, and eczema.

    PubMed

    Deng, Qihong; Lu, Chan; Li, Yuguo; Sundell, Jan; Dan Norbäck

    2016-10-01

    Mounting evidence suggests that exposure to ambient air pollution is associated with the development of childhood allergic diseases, but the effect of prenatal exposure to air pollution on the risk of childhood asthma and allergy is unclear. We evaluated the association between maternal exposure to outdoor air pollution during different trimesters of pregnancy and incidence of asthma, allergic rhinitis, and eczema in 2598 preschool children aged 3-6 years in China. Children's lifetime incidence of allergic diseases was obtained using questionnaire. Individual exposure to outdoor air pollutants during trimesters of pregnancy was estimated by an inverse distance weighted (IDW) method based on the measured concentrations at monitoring stations. We used multiple logistic regression method to estimate the odds ratio (OR) of asthma, allergic rhinitis, and eczema for per interquartile range (IQR) increase in the exposure to air pollutant in each trimester, which was adjusted for the effect of other air pollutants and its effect in other trimesters by a multi-pollutant/trimester model. Incidence of asthma (6.8%), allergic rhinitis (7.3%), and eczema (28.6%) in children was associated with maternal exposure to traffic-related pollutant NO2 during entire pregnancy with OR (95% confidence interval [CI]) respectively 1.63 (0.99-2.70), 1.69 (1.03-2.77), and 1.37 (1.04-1.80). After adjustment for other pollutants and trimesters, we found the association was significant only in specific trimester: the first trimester for eczema (1.54, 1.14-2.09), the second trimester for asthma (1.72, 1.02-2.97), and the third trimester for allergic rhinitis (1.77, 1.09-2.89). Sensitivity analysis indicated that the trimester sensitive to the development of allergic diseases was stable. Maternal exposure to traffic-related air pollutant NO2 during pregnancy, especially in specific trimesters, is associated with an increased risk of developing asthma, rhinitis, and eczema in children. Our results

  2. Ambient air pollution exposure and full-term birth weight in California.

    PubMed

    Morello-Frosch, Rachel; Jesdale, Bill M; Sadd, James L; Pastor, Manuel

    2010-07-28

    Studies have identified relationships between air pollution and birth weight, but have been inconsistent in identifying individual pollutants inversely associated with birth weight or elucidating susceptibility of the fetus by trimester of exposure. We examined effects of prenatal ambient pollution exposure on average birth weight and risk of low birth weight in full-term births. We estimated average ambient air pollutant concentrations throughout pregnancy in the neighborhoods of women who delivered term singleton live births between 1996 and 2006 in California. We adjusted effect estimates of air pollutants on birth weight for infant characteristics, maternal characteristics, neighborhood socioeconomic factors, and year and season of birth. 3,545,177 singleton births had monitoring for at least one air pollutant within a 10 km radius of the tract or ZIP Code of the mother's residence. In multivariate models, pollutants were associated with decreased birth weight; -5.4 grams (95% confidence interval -6.8 g, -4.1 g) per ppm carbon monoxide, -9.0 g (-9.6 g, -8.4 g) per pphm nitrogen dioxide, -5.7 g (-6.6 g, -4.9 g) per pphm ozone, -7.7 g (-7.9 g, -6.6 g) per 10 microg/m3 particulate matter under 10 microm, -12.8 g (-14.3 g, -11.3 g) per 10 microg/m3 particulate matter under 2.5 microm, and -9.3 g (-10.7 g, -7.9 g) per 10 microg/m3 of coarse particulate matter. With the exception of carbon monoxide, estimates were largely unchanged after controlling for co-pollutants. Effect estimates for the third trimester largely reflect the results seen from full pregnancy exposure estimates; greater variation in results is seen in effect estimates specific to the first and second trimesters. This study indicates that maternal exposure to ambient air pollution results in modestly lower infant birth weight. A small decline in birth weight is unlikely to have clinical relevance for individual infants, and there is debate about whether a small shift in the population distribution of

  3. Ambient air pollution exposure and full-term birth weight in California

    PubMed Central

    2010-01-01

    Background Studies have identified relationships between air pollution and birth weight, but have been inconsistent in identifying individual pollutants inversely associated with birth weight or elucidating susceptibility of the fetus by trimester of exposure. We examined effects of prenatal ambient pollution exposure on average birth weight and risk of low birth weight in full-term births. Methods We estimated average ambient air pollutant concentrations throughout pregnancy in the neighborhoods of women who delivered term singleton live births between 1996 and 2006 in California. We adjusted effect estimates of air pollutants on birth weight for infant characteristics, maternal characteristics, neighborhood socioeconomic factors, and year and season of birth. Results 3,545,177 singleton births had monitoring for at least one air pollutant within a 10 km radius of the tract or ZIP Code of the mother's residence. In multivariate models, pollutants were associated with decreased birth weight; -5.4 grams (95% confidence interval -6.8 g, -4.1 g) per ppm carbon monoxide, -9.0 g (-9.6 g, -8.4 g) per pphm nitrogen dioxide, -5.7 g (-6.6 g, -4.9 g) per pphm ozone, -7.7 g (-7.9 g, -6.6 g) per 10 μg/m3 particulate matter under 10 μm, -12.8 g (-14.3 g, -11.3 g) per 10 μg/m3 particulate matter under 2.5 μm, and -9.3 g (-10.7 g, -7.9 g) per 10 μg/m3 of coarse particulate matter. With the exception of carbon monoxide, estimates were largely unchanged after controlling for co-pollutants. Effect estimates for the third trimester largely reflect the results seen from full pregnancy exposure estimates; greater variation in results is seen in effect estimates specific to the first and second trimesters. Conclusions This study indicates that maternal exposure to ambient air pollution results in modestly lower infant birth weight. A small decline in birth weight is unlikely to have clinical relevance for individual infants, and there is debate about whether a small shift in the

  4. Simulation of Population-Based Commuter Exposure to NO2 Using Different Air Pollution Models

    PubMed Central

    Ragettli, Martina S.; Tsai, Ming-Yi; Braun-Fahrländer, Charlotte; de Nazelle, Audrey; Schindler, Christian; Ineichen, Alex; Ducret-Stich, Regina E.; Perez, Laura; Probst-Hensch, Nicole; Künzli, Nino; Phuleria, Harish C.

    2014-01-01

    We simulated commuter routes and long-term exposure to traffic-related air pollution during commute in a representative population sample in Basel (Switzerland), and evaluated three air pollution models with different spatial resolution for estimating commute exposures to nitrogen dioxide (NO2) as a marker of long-term exposure to traffic-related air pollution. Our approach includes spatially and temporally resolved data on actual commuter routes, travel modes and three air pollution models. Annual mean NO2 commuter exposures were similar between models. However, we found more within-city and within-subject variability in annual mean (±SD) NO2 commuter exposure with a high resolution dispersion model (40 ± 7 µg m−3, range: 21–61) than with a dispersion model with a lower resolution (39 ± 5 µg m−3; range: 24–51), and a land use regression model (41 ± 5 µg m−3; range: 24–54). Highest median cumulative exposures were calculated along motorized transport and bicycle routes, and the lowest for walking. For estimating commuter exposure within a city and being interested also in small-scale variability between roads, a model with a high resolution is recommended. For larger scale epidemiological health assessment studies, models with a coarser spatial resolution are likely sufficient, especially when study areas include suburban and rural areas. PMID:24823664

  5. Modelling of human exposure to air pollution in the urban environment: a GPS-based approach.

    PubMed

    Dias, Daniela; Tchepel, Oxana

    2014-03-01

    The main objective of this work was the development of a new modelling tool for quantification of human exposure to traffic-related air pollution within distinct microenvironments by using a novel approach for trajectory analysis of the individuals. For this purpose, mobile phones with Global Positioning System technology have been used to collect daily trajectories of the individuals with higher temporal resolution and a trajectory data mining, and geo-spatial analysis algorithm was developed and implemented within a Geographical Information System to obtain time-activity patterns. These data were combined with air pollutant concentrations estimated for several microenvironments. In addition to outdoor, pollutant concentrations in distinct indoor microenvironments are characterised using a probabilistic approach. An example of the application for PM2.5 is presented and discussed. The results obtained for daily average individual exposure correspond to a mean value of 10.6 and 6.0-16.4 μg m(-3) in terms of 5th-95th percentiles. Analysis of the results shows that the use of point air quality measurements for exposure assessment will not explain the intra- and inter-variability of individuals' exposure levels. The methodology developed and implemented in this work provides time-sequence of the exposure events thus making possible association of the exposure with the individual activities and delivers main statistics on individual's air pollution exposure with high spatio-temporal resolution.

  6. Simulation of population-based commuter exposure to NO₂ using different air pollution models.

    PubMed

    Ragettli, Martina S; Tsai, Ming-Yi; Braun-Fahrländer, Charlotte; de Nazelle, Audrey; Schindler, Christian; Ineichen, Alex; Ducret-Stich, Regina E; Perez, Laura; Probst-Hensch, Nicole; Künzli, Nino; Phuleria, Harish C

    2014-05-12

    We simulated commuter routes and long-term exposure to traffic-related air pollution during commute in a representative population sample in Basel (Switzerland), and evaluated three air pollution models with different spatial resolution for estimating commute exposures to nitrogen dioxide (NO2) as a marker of long-term exposure to traffic-related air pollution. Our approach includes spatially and temporally resolved data on actual commuter routes, travel modes and three air pollution models. Annual mean NO2 commuter exposures were similar between models. However, we found more within-city and within-subject variability in annual mean (±SD) NO2 commuter exposure with a high resolution dispersion model (40 ± 7 µg m(-3), range: 21-61) than with a dispersion model with a lower resolution (39 ± 5 µg m(-3); range: 24-51), and a land use regression model (41 ± 5 µg m(-3); range: 24-54). Highest median cumulative exposures were calculated along motorized transport and bicycle routes, and the lowest for walking. For estimating commuter exposure within a city and being interested also in small-scale variability between roads, a model with a high resolution is recommended. For larger scale epidemiological health assessment studies, models with a coarser spatial resolution are likely sufficient, especially when study areas include suburban and rural areas.

  7. High resolution exposure modelling of heat and air pollution and the impact on mortality.

    PubMed

    Willers, Saskia M; Jonker, Marcel F; Klok, Lisette; Keuken, Menno P; Odink, Jennie; van den Elshout, Sef; Sabel, Clive E; Mackenbach, Johan P; Burdorf, Alex

    2016-01-01

    Elevated temperature and air pollution have been associated with increased mortality. Exposure to heat and air pollution, as well as the density of vulnerable groups varies within cities. The objective was to investigate the extent of neighbourhood differences in mortality risk due to heat and air pollution in a city with a temperate maritime climate. A case-crossover design was used to study associations between heat, air pollution and mortality. Different thermal indicators and air pollutants (PM10, NO2, O3) were reconstructed at high spatial resolution to improve exposure classification. Daily exposures were linked to individual mortality cases over a 15year period. Significant interaction between maximum air temperature (Tamax) and PM10 was observed. During "summer smog" days (Tamax>25°C and PM10>50μg/m(3)), the mortality risk at lag 2 was 7% higher compared to the reference (Tamax 15°C and PM10 15μg/m(3)). Persons above age 85 living alone were at highest risk. We found significant synergistic effects of high temperatures and air pollution on mortality. Single living elderly were the most vulnerable group. Due to spatial differences in temperature and air pollution, mortality risks varied substantially between neighbourhoods, with a difference up to 7%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Acute exacerbation of idiopathic pulmonary fibrosis associated with air pollution exposure.

    PubMed

    Johannson, Kerri A; Vittinghoff, Eric; Lee, Kiyoung; Balmes, John R; Ji, Wonjun; Kaplan, Gilaad G; Kim, Dong Soon; Collard, Harold R

    2014-04-01

    Acute exacerbations of idiopathic pulmonary fibrosis are associated with high mortality and are of unknown cause. The effect of air pollution on exacerbations of interstitial lung disease is unknown. This study aims to define the association of air pollution exposure with acute exacerbation of idiopathic pulmonary fibrosis. Patients with idiopathic pulmonary fibrosis and corresponding air pollution data were identified from a longitudinal cohort. Air pollution exposures were assigned to each patient for ozone, nitrogen dioxide, particulate matter, sulfur dioxide and carbon monoxide based on geo-coded residential addresses. Cox proportional hazards models were used to estimate the association of air pollution exposures and acute exacerbations. Acute exacerbation was significantly associated with antecedent 6-week increases in mean level, maximum level and number of exceedances above accepted standards of ozone (hazard ratio (HR) 1.57, 95% CI 1.09-2.24; HR 1.42, 95% CI 1.11-1.82; and HR 1.51, 95% CI 1.17-1.94, respectively) and nitrogen dioxide (HR 1.41, 95% CI 1.04-1.91; HR 1.27, 95% CI 1.01-1.59; and HR 1.20, 95% CI 1.10-1.31, respectively). Increased ozone and nitrogen dioxide exposure over the preceding 6 weeks was associated with an increased risk of acute exacerbation of idiopathic pulmonary fibrosis, suggesting that air pollution may contribute to the development of this clinically meaningful event.

  9. Destructive and non-destructive determination of the transport current density radial distribution: Application to Bi-2212 textured rods

    NASA Astrophysics Data System (ADS)

    Martínez, E.; Natividad, E.; Angurel, L. A.; Navarro, R.; Yang, Y.; Beduz, C.

    2003-03-01

    Destructive and non-destructive methods to estimate the radial distribution of the transport critical current, Jc( r), of long cylindrical superconductors are presented. The non-destructive method is based on the measurement of self-field AC losses as a function of the current amplitude, Q( I0) and takes into account the E- J characteristics of the material. Both methods have been used to derive the Jc( r) profiles of long and thin Bi-2212 rods textured by laser-induced zone melting techniques. The obtained results have been correlated with the microstructure of the samples and their critical temperature.

  10. Cyclist route choice, traffic-related air pollution, and lung function: a scripted exposure study.

    PubMed

    Jarjour, Sarah; Jerrett, Michael; Westerdahl, Dane; de Nazelle, Audrey; Hanning, Cooper; Daly, Laura; Lipsitt, Jonah; Balmes, John

    2013-02-07

    A travel mode shift to active transportation such as bicycling would help reduce traffic volume and related air pollution emissions as well as promote increased physical activity level. Cyclists, however, are at risk for exposure to vehicle-related air pollutants due to their proximity to vehicle traffic and elevated respiratory rates. To promote safe bicycle commuting, the City of Berkeley, California, has designated a network of residential streets as "Bicycle Boulevards." We hypothesized that cyclist exposure to air pollution would be lower on these Bicycle Boulevards when compared to busier roads and this elevated exposure may result in reduced lung function. We recruited 15 healthy adults to cycle on two routes - a low-traffic Bicycle Boulevard route and a high-traffic route. Each participant cycled on the low-traffic route once and the high-traffic route once. We mounted pollutant monitors and a global positioning system (GPS) on the bicycles. The monitors were all synced to GPS time so pollutant measurements could be spatially plotted. We measured lung function using spirometry before and after each bike ride. We found that fine and ultrafine particulate matter, carbon monoxide, and black carbon were all elevated on the high-traffic route compared to the low-traffic route. There were no corresponding changes in the lung function of healthy non-asthmatic study subjects. We also found that wind-speed affected pollution concentrations. These results suggest that by selecting low-traffic Bicycle Boulevards instead of heavily trafficked roads, cyclists can reduce their exposure to vehicle-related air pollution. The lung function results indicate that elevated pollutant exposure may not have acute negative effects on healthy cyclists, but further research is necessary to determine long-term effects on a more diverse population. This study and broader field of research have the potential to encourage policy-makers and city planners to expand infrastructure to

  11. Effects of Exposure Measurement Error in the Analysis of Health Effects from Traffic-Related Air Pollution

    EPA Science Inventory

    In large epidemiological studies, many researchers use surrogates of air pollution exposure such as geographic information system (GIS)-based characterizations of traffic or simple housing characteristics. It is important to validate these surrogates against measured pollutant co...

  12. Heterogeneity of passenger exposure to air pollutants in public transport microenvironments

    NASA Astrophysics Data System (ADS)

    Yang, Fenhuan; Kaul, Daya; Wong, Ka Chun; Westerdahl, Dane; Sun, Li; Ho, Kin-fai; Tian, Linwei; Brimblecombe, Peter; Ning, Zhi

    2015-05-01

    Epidemiologic studies have linked human exposure to pollutants with adverse health effects. Passenger exposure in public transport systems contributes an important fraction of daily burden of air pollutants. While there is extensive literature reporting the concentrations of pollutants in public transport systems in different cities, there are few studies systematically addressing the heterogeneity of passenger exposure in different transit microenvironments, in cabins of different transit vehicles and in areas with different characteristics. The present study investigated PM2.5 (particulate matter with aerodynamic diameters smaller than 2.5 μm), black carbon (BC), ultrafine particles (UFP) and carbon monoxide (CO) pollutant concentrations in various public road transport systems in highly urbanized city of Hong Kong. Using a trolley case housing numerous portable air monitors, we conducted a total of 119 trips during the campaign. Transit microenvironments, classified as 1). busy and secondary roadside bus stops; 2). open and enclosed termini; 3). above- and under-ground Motor Rail Transport (MTR) platforms, were investigated and compared to identify the factors that may affect passenger exposures. The pollutants inside bus and MTR cabins were also investigated together with a comparison of time integrated exposure between the transit modes. Busy roadside and enclosed termini demonstrated the highest average particle concentrations while the lowest was found on the MTR platforms. Traffic-related pollutants BC, UFP and CO showed larger variations than PM2.5 across different microenvironments and areas confirming their heterogeneity in urban environments. In-cabin pollutant concentrations showed distinct patterns with BC and UFP high in diesel bus cabins and CO high in LPG bus cabins, suggesting possible self-pollution issues and/or penetration of on-road pollutants inside cabins during bus transit. The total passenger exposure along selected routes, showed bus

  13. Source location of air pollution and cardiac autonomic function: trajectory cluster analysis for exposure assessment.

    PubMed

    Park, Sung Kyun; O'Neill, Marie S; Stunder, Barbara J B; Vokonas, Pantel S; Sparrow, David; Koutrakis, Petros; Schwartz, Joel

    2007-08-01

    Although many studies report that exposure to air pollution harms health, few have examined associations between pollution sources and health outcomes. We hypothesized that pollution originating in different locations has different associations with heart rate variability (HRV) among 497 men from the Normative Aging Study in Boston, Massachusetts. We identified the paths that air masses traveled ('back-trajectories') before arriving in Boston on the days the men were examined. Next, we classified these trajectories into six clusters. We examined whether the association of measured air pollutants with HRV (standard deviation of normal-to-normal intervals, high-frequency power (HF) and low-frequency power (LF), and LF/HF ratio) differed by cluster. We also examined whether the clusters alone (not considering air pollution measurements) showed different associations with HRV. The effects of black carbon (BC) on all HRV measures were strongest on days with southwest trajectories. Subjects who were examined on days where air parcels came from west had the strongest associations with ozone. All particle pollutants (particulate matter <2.5 microm in aerodynamic diameter (PM2.5), BC, and sulfates) were associated with increased LF/HF ratio on days with relatively short trajectories, which are related to local, slow-moving air masses. We also observed significant increases in LF/HF in days where air came from the northwest and west, compared to north trajectory days. Health effects associated with exposure to air pollution can be evaluated using pollutant concentrations as well as aspects of the pollution mixture captured by identifying locations where air masses originate. Independent effects of both these indicators of pollution exposure were seen on cardiac autonomic function.

  14. Selection of native plants with phytoremediation potential for highly contaminated Mediterranean soil restoration: Tools for a non-destructive and integrative approach.

    PubMed

    Heckenroth, Alma; Rabier, Jacques; Dutoit, Thierry; Torre, Franck; Prudent, Pascale; Laffont-Schwob, Isabelle

    2016-12-01

    The aim of this study was to develop an effective and non-destructive method for the selection of native Mediterranean plants with phytoremediation potential based on their spontaneous recovery capacities. The study site consisted in a mixed contaminated soils (As, Cu, Pb, Sb, Zn) in the vicinity of a former lead smelting factory abandoned since 1925 in the Calanques National Park (Marseille, southeastern France). We developed an integrated characterization approach that takes into account topsoil metal(loid)s (MM) contamination, plant community composition and structure and mesologic parameters without using destructive methods. From a statistical selection of significant environmental descriptors, plant communities were described and interpreted as the result of spontaneous recovery under multiple stresses and local conditions (both natural and anthropogenic). We collected phytoecological and MM topsoil data using field monitoring and geographic information system (GIS) on a pollution hotspot where natural plant communities occur. The results of the multivariate analysis performed between species and descriptors indicated that a century of MM pollution pressure produced a significant correlation with plant community dynamics in terms of composition, diversity and structure, leading to the co-occurrence of different plant succession stages. Thus, these successions seemed linked to the variability of anthropogenic disturbance regimes within the study site. We recorded high topsoil contamination heterogeneity at the scale both of the plot and of the whole study area that suggested a heterogeneous MM distribution pattern dependent on the source of contaminants and site environmental variability. We identified 4 spontaneous plant communities co-occurring through a MM contamination gradient that could be used later from degraded to reference communities to define ecological restoration target combined to phytoremediation applications with respect to local conditions

  15. Arsenic pesticides and environmental pollution: exposure, poisoning, hazards and recommendations.

    PubMed

    El-Bahnasawy, Mamdouh M; Mohammad, Amina El-Hosini; Morsy, Tosson A

    2013-08-01

    Arsenic is a metalloid element. Acute high-dose exposure to arsenic can cause severe systemic toxicity and death. Lower dose chronic arsenic exposure can result in subacute toxicity that can include peripheral sensorimotor neuropathy, skin eruptions, and hepatotoxicity. Long-term effects of arsenic exposure include an in Due to the physiologic effects of the arsenic on all body systems, thus, chronic arsenic-poisoned patient is a major nursing challenge. The critical care nurse provides valuable assessment and interventions that prevent major multisystem complications from arsenic toxicity.

  16. An assessment of air pollutant exposure methods in Mexico City, Mexico.

    PubMed

    Rivera-González, Luis O; Zhang, Zhenzhen; Sánchez, Brisa N; Zhang, Kai; Brown, Daniel G; Rojas-Bracho, Leonora; Osornio-Vargas, Alvaro; Vadillo-Ortega, Felipe; O'Neill, Marie S

    2015-05-01

    Geostatistical interpolation methods to estimate individual exposure to outdoor air pollutants can be used in pregnancy cohorts where personal exposure data are not collected. Our objectives were to a) develop four assessment methods (citywide average (CWA); nearest monitor (NM); inverse distance weighting (IDW); and ordinary Kriging (OK)), and b) compare daily metrics and cross-validations of interpolation models. We obtained 2008 hourly data from Mexico City's outdoor air monitoring network for PM10, PM2.5, O3, CO, NO2, and SO2 and constructed daily exposure metrics for 1,000 simulated individual locations across five populated geographic zones. Descriptive statistics from all methods were calculated for dry and wet seasons, and by zone. We also evaluated IDW and OK methods' ability to predict measured concentrations at monitors using cross validation and a coefficient of variation (COV). All methods were performed using SAS 9.3, except ordinary Kriging which was modeled using R's gstat package. Overall, mean concentrations and standard deviations were similar among the different methods for each pollutant. Correlations between methods were generally high (r=0.77 to 0.99). However, ranges of estimated concentrations determined by NM, IDW, and OK were wider than the ranges for CWA. Root mean square errors for OK were consistently equal to or lower than for the IDW method. OK standard errors varied considerably between pollutants and the computed COVs ranged from 0.46 (least error) for SO2 and PM10 to 3.91 (most error) for PM2.5. OK predicted concentrations measured at the monitors better than IDW and NM. Given the similarity in results for the exposure methods, OK is preferred because this method alone provides predicted standard errors which can be incorporated in statistical models. The daily estimated exposures calculated using these different exposure methods provide flexibility to evaluate multiple windows of exposure during pregnancy, not just trimester or

  17. Interactions of GST Polymorphisms in Air Pollution Exposure and Respiratory Diseases and Allergies.

    PubMed

    Bowatte, Gayan; Lodge, Caroline J; Perret, Jennifer L; Matheson, Melanie C; Dharmage, Shyamali C

    2016-11-01

    The purpose of this review is to summarize the evidence from recently published original studies investigating how glutathione S-transferase (GST) gene polymorphisms modify the impact of air pollution on asthma, allergic diseases, and lung function. Current studies in epidemiological and controlled human experiments found evidence to suggest that GSTs modify the impact of air pollution exposure on respiratory diseases and allergies. Of the nine articles included in this review, all except one identified at least one significant interaction with at least one of glutathione S-transferase pi 1 (GSTP1), glutathione S-transferase mu 1 (GSTM1), or glutathione S-transferase theta 1 (GSTT1) genes and air pollution exposure. The findings of these studies, however, are markedly different. This difference can be partially explained by regional variation in the exposure levels and oxidative potential of different pollutants and by other interactions involving a number of unaccounted environment exposures and multiple genes. Although there is evidence of an interaction between GST genes and air pollution exposure for the risk of respiratory disease and allergies, results are not concordant. Further investigations are needed to explore the reasons behind the discordancy.

  18. Methods for assessing the extent of exposure and effects of air pollution.

    PubMed Central

    Krzyzanowski, M

    1997-01-01

    BACKGROUND AND OBJECTIVES: In many places in Europe, the ambient air pollution exceeds the levels considered to be safe for health. The objective of the paper is to review and summarise the methods of assessment of its impact on health, and to indicate the contributions of various research disciplines, particularly environmental epidemiology. METHODS: The framework for assessment of impact is based on a four stage model: assessment of release of pollutant; assessment of exposure; assessment of the consequence; and risk estimation. RESULTS: Epidemiology is crucial in providing the data for the assessment of consequence. The criteria that determine the use of epidemiological studies for this task include lack of bias, correct control of confounding, and measured estimates of exposure. At present, those criteria are easier to satisfy for studies of short term effects on health than for the delayed consequences of exposure, or exposure accumulated over a prolonged period. Combinations of results from various populations through meta-analysis of existing studies or conducting multicentre studies is often necessary to increase the reliability of the consequence assessment stage. CONCLUSION: To assess the impact on health systematically helps to focus on actions to limit air pollutants with the greatest impacts on human health and on the most affected populations. This method allows identification of the most pertinent questions which have to be answered by studies on relations between pollution and health and on exposure of populations to air pollutants. Epidemiology has considerable potential to contribute to this research. PMID:9155775

  19. Climate change impacts on human exposures to air pollution

    EPA Science Inventory

    This is an abstract for a presentations at the Annual Conference of the International Society on Exposure Science and Environmental Epidemiology. This presentation will serve as an introduction to the symposium.

  20. Climate change impacts on human exposures to air pollution

    EPA Science Inventory

    This is an abstract for a presentations at the Annual Conference of the International Society on Exposure Science and Environmental Epidemiology. This presentation will serve as an introduction to the symposium.

  1. Spatial-Temporal Modeling of the Association between Air Pollution Exposure and Preterm Birth: Identifying Critical Windows of Exposure

    PubMed Central

    Fuentes, Montserrat; Herring, Amy; Langlois, Peter

    2012-01-01

    Summary Exposure to high levels of air pollution during the pregnancy is associated with increased probability of preterm birth (PTB), a major cause of infant morbidity and mortality. New statistical methodology is required to specifically determine when a particular pollutant impacts the PTB outcome, to determine the role of different pollutants, and to characterize the spatial variability in these results. We develop a new Bayesian spatial model for PTB which identifies susceptible windows throughout the pregnancy jointly for multiple pollutants (PM2.5, ozone) while allowing these windows to vary continuously across space and time. We geo-code vital record birth data from Texas (2002–2004) and link them with standard pollution monitoring data and a newly introduced EPA product of calibrated air pollution model output. We apply the fully spatial model to a region of 13 counties in eastern Texas consisting of highly urban as well as rural areas. Our results indicate significant signal in the first two trimesters of pregnancy with differe0nt pollutants leading to different critical windows. Introducing the spatial aspect uncovers critical windows previously unidentified when space is ignored. A proper inference procedure is introduced to correctly analyze these windows. PMID:22568640

  2. Spatial-temporal modeling of the association between air pollution exposure and preterm birth: identifying critical windows of exposure.

    PubMed

    Warren, Joshua; Fuentes, Montserrat; Herring, Amy; Langlois, Peter

    2012-12-01

    Exposure to high levels of air pollution during the pregnancy is associated with increased probability of preterm birth (PTB), a major cause of infant morbidity and mortality. New statistical methodology is required to specifically determine when a particular pollutant impacts the PTB outcome, to determine the role of different pollutants, and to characterize the spatial variability in these results. We develop a new Bayesian spatial model for PTB which identifies susceptible windows throughout the pregnancy jointly for multiple pollutants (PM(2.5) , ozone) while allowing these windows to vary continuously across space and time. We geo-code vital record birth data from Texas (2002-2004) and link them with standard pollution monitoring data and a newly introduced EPA product of calibrated air pollution model output. We apply the fully spatial model to a region of 13 counties in eastern Texas consisting of highly urban as well as rural areas. Our results indicate significant signal in the first two trimesters of pregnancy with different pollutants leading to different critical windows. Introducing the spatial aspect uncovers critical windows previously unidentified when space is ignored. A proper inference procedure is introduced to correctly analyze these windows.

  3. Non-destructive Phenotyping of Lettuce Plants in Early Stages of Development with Optical Sensors

    PubMed Central

    Simko, Ivan; Hayes, Ryan J.; Furbank, Robert T.

    2016-01-01

    Rapid development of plants is important for the production of ‘baby-leaf’ lettuce that is harvested when plants reach the four- to eight-leaf stage of growth. However, environmental factors, such as high or low temperature, or elevated concentrations of salt, inhibit lettuce growth. Therefore, non-destructive evaluations of plants can provide valuable information to breeders and growers. The objective of the present study was to test the feasibility of using non-destructive phenotyping with optical sensors for the evaluations of lettuce plants in early stages of development. We performed the series of experiments to determine if hyperspectral imaging and chlorophyll fluorescence imaging can determine phenotypic changes manifested on lettuce plants subjected to the extreme temperature and salinity stress treatments. Our results indicate that top view optical sensors alone can accurately determine plant size to approximately 7 g fresh weight. Hyperspectral imaging analysis was able to detect changes in the total chlorophyll (RCC) and anthocyanin (RAC) content, while chlorophyll fluorescence imaging revealed photoinhibition and reduction of plant growth caused by the extreme growing temperatures (3 and 39°C) and salinity (100 mM NaCl). Though no significant correlation was found between Fv/Fm and decrease in plant growth due to stress when comparisons were made across multiple accessions, our results indicate that lettuce plants have a high adaptability to both low (3°C) and high (39°C) temperatures, with no permanent damage to photosynthetic apparatus and fast recovery of plants after moving them to the optimal (21°C) temperature. We have also detected a strong relationship between visual rating of the green- and red-leaf color intensity and RCC and RAC, respectively. Differences in RAC among accessions suggest that the selection for intense red color may be easier to perform at somewhat lower than the optimal temperature. This study serves as a proof of

  4. Non-destructive testing for the structures and civil infrastructures characterization

    NASA Astrophysics Data System (ADS)

    Capozzoli, L.; Rizzo, E.

    2012-04-01

    infrared thermography and sonic testing. Finally, we investigated a radiant floor by GPR (900 MHz to 2000 MHz antennas) and long-wave infrared camera. Non-destructive diagnostic techniques allow to investigate a building structure in reinforced concrete or masonry without altering the characteristics of the element investigated. For this reason, geo-electrical and electromagnetic surveys of masonry are a suitable non-destructive tool for the diagnosis of a deteriorated concrete structure. Moreover, the integration of different NDT techniques (conventional and no-conventional) is a very powerful to maximize the capabilities and to compensate for the limitations of each method.

  5. Non-destructive Assessment of Plant Nitrogen Parameters Using Leaf Chlorophyll Measurements in Rice

    PubMed Central

    Ata-Ul-Karim, Syed Tahir; Cao, Qiang; Zhu, Yan; Tang, Liang; Rehmani, Muhammad Ishaq Asif; Cao, Weixing

    2016-01-01

    Non-destructive assessment of plant nitrogen (N) status is essential for efficient crop production and N management in intensive rice (Oryza sativa L.) cropping systems. Chlorophyll meter (SPAD-502) has been widely used as a rapid, non-destructive and cost-effective diagnostic tool for in-season assessment of crop N status. The present study was intended to establish the quantitative relationships between chlorophyll meters readings, plant N concentration (PNC), N nutrition index (NNI), accumulated N deficit (AND), and N requirement (NR), as well as to compare the stability of these relationships at different vegetative growth stages in Japonica and Indica rice cultivars. Seven multi-locational field experiments using varied N rates and seven rice cultivars were conducted in east China. The results showed that the PNC and chlorophyll meters readings increased with increasing N application rates across the cultivars, growing seasons, and sites. The PNC and chlorophyll meters readings under varied N rates ranged from 2.29 to 3.21, 1.06 to 1.82 and 37.10 to 45.4 and 37.30 to 46.6, respectively, at TL and HD stages for Japonica rice cultivars, while they ranged from 2.25 to 3.23, 1.34 to 1.91 and 35.6 to 43.3 and 37.3 to 45.5 for Indica rice cultivars, respectively. The quantitative relationships between chlorophyll meters readings, PNC, NNI, AND, and NR established at different crop growth stages in two rice ecotypes, were highly significant with R2 values ranging from 0.69 to 0.93 and 0.71 to 0.86 for Japonica and Indica rice, respectively. The strongest relationships were observed for AND and NR at panicle initiation and booting stages in both rice ecotypes. The validation of the relationships developed in the present study with an independent data exhibited a solid model performance and confirmed their robustness as a reliable and rapid diagnostic tool for in-season estimation of plant N parameters for sustainable N management in rice. The results of this study

  6. Accuracy of Non-Destructive Testing of PBRs to Estimate Fragilities

    NASA Astrophysics Data System (ADS)

    Brune, J. N.; Brune, R.; Biasi, G. P.; Anooshehpoor, R.; Purvance, M.

    2011-12-01

    Prior studies of Precariously Balanced Rocks (PBRs) have involved various methods of documenting rock shapes and fragilities. These have included non-destructive testing (NDT) methods such as photomodeling, and potentially destructive testing (PDT) such as forced tilt tests. PDT methods usually have the potential of damaging or disturbing the rock or its pedestal so that the PBR usefulness for future generations is compromised. To date we have force-tilt tested approximately 28 PBRs, and of these we believe 7 have been compromised. We suggest here that given other inherent uncertainties in the current methodologies, NDT methods are now sufficiently advanced as to be adequate for the current state of the art use for comparison with Ground Motion Prediction Equations (GMPEs) and seismic hazard maps (SHMs). Here we compare tilt-test static toppling estimates to three non-destructive methods: (1) 3-D photographic modeling (2) profile analysis assuming the rock is 2-D, and (3) expert judgments from photographs. 3-D modeling uses the commercial Photomodeler program and photographs in the field taken from numerous directions around the rock. The output polyhedral shape is analyzed in Matlab determine the center of mass and in Autocad to estimate the static overturning angle alpha. For the 2-D method we chose the photograph in profile looking perpendicular to the estimated direction of toppling. The rock is outlined as a 2-D object in Matlab. Rock dimensions, rocking points, and a vertical reference are supplied by the photo analyst to estimate the center of gravity and static force overturning angles. For the expert opinion method we used additional photographs taken from different directions to improve the estimates of the center of mass and the rocking points. We used 7 rocks for comparisons. The error in estimating tan alpha from 3-D modeling is about 0.05. For 2-D estimates an average error is about 0.1 (?). For expert opinion estimates the error is about 0.06. For

  7. Non-destructive evaluation of containment walls in nuclear power plants

    NASA Astrophysics Data System (ADS)

    Garnier, V.; Payan, C.; Lott, M.; Ranaivomanana, N.; Balayssac, J. P.; Verdier, J.; Larose, E.; Zhang, Y.; Saliba, J.; Boniface, A.; Sbartai, Z. M.; Piwakowski, B.; Ciccarone, C.; Hafid, H.; Henault, J. M.; Buffet, F. Ouvrier

    2017-02-01

    Two functions are regularly tested on containment walls in order to anticipate a possible accident. The first is mechanical to resist a possible internal over-pressure and the second is to prevent leakage. The AAPR reference accident is the rupture of a pipe in the primary circuit of a nuclear plant. In this case, the pressure and temperature can reach 5 bar and 180°C in 20 seconds. The national project `Non-destructive testing of the containment structures of nuclear plants' aims at studying the non-destructive techniques capable to evaluate the concrete properties and its damaging and cracks. This 4-year-project is segmented into two parts. The first consists in developing and selecting the most relevant NDEs in the laboratory to reach these goals. These evaluations are developed in conditions representing the real conditions of the stresses generated during ten-yearly visits of the plants or those related to an accident. The second part consists in applying the selected techniques to two containment structures under pressure. The first structure is proposed by ONERA and the second is a mockup of a containment wall on a 1/3 scale made by EDF within the VeRCoRs project. Communication is focused on the part of the project that concerns the damage and crack process characterization by means of NDT. The tests are done in 3 or 4 points bending in order to study the cracks' generation, their propagation, as well as their opening and closing. The main ultrasonic techniques developed concern linear or non-linear acoustic: acoustic emission [1], Locadiff [2], energy diffusion, surface wave's velocity and attenuation, DAET [3]. The recorded data contribute to providing the mapping of the investigated parameters, either in volume, in surface or globally. Digital image correlation is an important additional asset to validate the coherence of the data. The spatial normalization of the data in the specimen space allows proposing algorithms on the combination of the

  8. Non-destructive Assessment of Plant Nitrogen Parameters Using Leaf Chlorophyll Measurements in Rice.

    PubMed

    Ata-Ul-Karim, Syed Tahir; Cao, Qiang; Zhu, Yan; Tang, Liang; Rehmani, Muhammad Ishaq Asif; Cao, Weixing

    2016-01-01

    Non-destructive assessment of plant nitrogen (N) status is essential for efficient crop production and N management in intensive rice (Oryza sativa L.) cropping systems. Chlorophyll meter (SPAD-502) has been widely used as a rapid, non-destructive and cost-effective diagnostic tool for in-season assessment of crop N status. The present study was intended to establish the quantitative relationships between chlorophyll meters readings, plant N concentration (PNC), N nutrition index (NNI), accumulated N deficit (AND), and N requirement (NR), as well as to compare the stability of these relationships at different vegetative growth stages in Japonica and Indica rice cultivars. Seven multi-locational field experiments using varied N rates and seven rice cultivars were conducted in east China. The results showed that the PNC and chlorophyll meters readings increased with increasing N application rates across the cultivars, growing seasons, and sites. The PNC and chlorophyll meters readings under varied N rates ranged from 2.29 to 3.21, 1.06 to 1.82 and 37.10 to 45.4 and 37.30 to 46.6, respectively, at TL and HD stages for Japonica rice cultivars, while they ranged from 2.25 to 3.23, 1.34 to 1.91 and 35.6 to 43.3 and 37.3 to 45.5 for Indica rice cultivars, respectively. The quantitative relationships between chlorophyll meters readings, PNC, NNI, AND, and NR established at different crop growth stages in two rice ecotypes, were highly significant with R(2) values ranging from 0.69 to 0.93 and 0.71 to 0.86 for Japonica and Indica rice, respectively. The strongest relationships were observed for AND and NR at panicle initiation and booting stages in both rice ecotypes. The validation of the relationships developed in the present study with an independent data exhibited a solid model performance and confirmed their robustness as a reliable and rapid diagnostic tool for in-season estimation of plant N parameters for sustainable N management in rice. The results of this study

  9. Non-destructive Phenotyping of Lettuce Plants in Early Stages of Development with Optical Sensors.

    PubMed

    Simko, Ivan; Hayes, Ryan J; Furbank, Robert T

    2016-01-01

    Rapid development of plants is important for the production of 'baby-leaf' lettuce that is harvested when plants reach the four- to eight-leaf stage of growth. However, environmental factors, such as high or low temperature, or elevated concentrations of salt, inhibit lettuce growth. Therefore, non-destructive evaluations of plants can provide valuable information to breeders and growers. The objective of the present study was to test the feasibility of using non-destructive phenotyping with optical sensors for the evaluations of lettuce plants in early stages of development. We performed the series of experiments to determine if hyperspectral imaging and chlorophyll fluorescence imaging can determine phenotypic changes manifested on lettuce plants subjected to the extreme temperature and salinity stress treatments. Our results indicate that top view optical sensors alone can accurately determine plant size to approximately 7 g fresh weight. Hyperspectral imaging analysis was able to detect changes in the total chlorophyll (RCC) and anthocyanin (RAC) content, while chlorophyll fluorescence imaging revealed photoinhibition and reduction of plant growth caused by the extreme growing temperatures (3 and 39°C) and salinity (100 mM NaCl). Though no significant correlation was found between Fv/Fm and decrease in plant growth due to stress when comparisons were made across multiple accessions, our results indicate that lettuce plants have a high adaptability to both low (3°C) and high (39°C) temperatures, with no permanent damage to photosynthetic apparatus and fast recovery of plants after moving them to the optimal (21°C) temperature. We have also detected a strong relationship between visual rating of the green- and red-leaf color intensity and RCC and RAC, respectively. Differences in RAC among accessions suggest that the selection for intense red color may be easier to perform at somewhat lower than the optimal temperature. This study serves as a proof of concept

  10. Preconceptional and perinatal exposure to traffic-related air pollution and eczema in preschool children.

    PubMed

    Lu, Chan; Deng, Linjing; Ou, Cuiyun; Yuan, Hong; Chen, Xiang; Deng, Qihong

    2017-02-01

    Evidence linking prenatal exposure to outdoor air pollution with eczema in early childhood is scare, and the role of components of air pollution and exposure timing remains unclear. We investigated the association between exposure to air pollution during preconceptional and perinatal period and the risk of eczema in preschool children. We conducted a prospective cohort study of 2598 children aged 3-6 years in Changsha, China. The prevalence of eczema was assessed by a standardized health questionnaire administered by the parents. Individual exposures to nitrogen dioxide (NO2), sulfur dioxide (SO2) and particulate matter with an aerodynamic diameter≤10μm (PM10) during the 4th-6th and 1st-3rd month before pregnancy, entire pregnancy, and three trimesters were estimated by an inverse distance weighted (IDW) method based on concentrations measured at monitoring stations. Association between childhood eczema and exposure to air pollution was examined by logistic regression models in terms of odds ratio (OR) and 95% confidence interval (CI) for an interquartile range (IQR) increase in exposure. Life-time prevalence of eczema in preschool children in Changsha was 28.6%. Childhood eczema was associated with traffic-related air pollutant NO2 during 3 months before pregnancy and entire pregnancy with adjusted ORs=1.19 (95% CI: 1.04-1.37) and 1.21 (95% CI: 1.03-1.42) respectively. The highest risk of eczema was observed for the 1st trimester exposure to NO2 [OR=1.26 (95% CI: 1.09-1.46)]. However, no association was detected for SO2 and PM10 exposure during any window. High-level exposure to NO2 during the whole time period significantly increased the effect of NO2 in all windows on eczema risk as compared with low-level exposure. Sensitivity analysis indicated that the association between both preconceptional and perinatal exposure to NO2 and childhood eczema was consistent and robust, and this association was modified by some personal, parental hereditary and indoor

  11. Early life exposure to ambient air pollution and childhood asthma in China.

    PubMed

    Deng, Qihong; Lu, Chan; Norbäck, Dan; Bornehag, Carl-Gustaf; Zhang, Yinping; Liu, Weiwei; Yuan, Hong; Sundell, Jan

    2015-11-01

    Early life is suggested to be a critical time in determining subsequent asthma development, but the extent to which the effect of early-life exposure to ambient air pollution on childhood asthma is unclear. We investigated doctor-diagnosed asthma in preschool children due to exposure to ambient air pollution in utero and during the first year of life. In total 2490 children aged 3-6 years participated in a questionnaire study regarding doctor-diagnosed asthma between September 2011 and January 2012 in China. Children's exposure to critical air pollutants, sulfur dioxide (SO2) as proxy of industrial air pollution, nitrogen dioxide (NO2) as proxy of traffic pollution, and particulate matter≤10µm in diameter (PM10) as a mixture, was estimated from the concentrations measured at the ambient air quality monitoring stations by using an inverse distance weighted (IDW) method. Logistic regression analysis was employed to determine the relationship between early-life exposure and childhood asthma in terms of odds ratio (OR) and 95% confidence interval (CI). Association between early-life exposure to air pollutants and childhood asthma was observed. SO2 and NO2 had significant associations with adjusted OR (95% CI) of 1.45 (1.02-2.07) and 1.74 (1.15-2.62) in utero and 1.62 (1.01-2.60) and 1.90 (1.20-3.00) during the first year for per 50 µg/m(3) and 15 µg/m(3) increase respectively. Exposure to the combined high level of SO2 and NO2 in China significantly elevated the asthmatic risk with adjusted OR (95% CI) of 1.76 (1.18-2.64) in utero and 1.85 (1.22-2.79) during the first year compared to the low level exposure. The associations were higher for males and the younger children aged 3-4 than females and the older children aged 5-6. Early-life exposure to ambient air pollution is associated with childhood asthma during which the level and source of air pollution play important roles. The high level and nature of combined industrial and traffic air pollution in China may

  12. Air Pollution Exposure During Pregnancy and Fetal Markers of Metabolic function: The MIREC Study.

    PubMed

    Lavigne, Eric; Ashley-Martin, Jillian; Dodds, Linda; Arbuckle, Tye E; Hystad, Perry; Johnson, Markey; Crouse, Dan L; Ettinger, Adrienne S; Shapiro, Gabriel D; Fisher, Mandy; Morisset, Anne-Sophie; Taback, Shayne; Bouchard, Maryse F; Sun, Liu; Monnier, Patricia; Dallaire, Renée; Fraser, William D

    2016-05-01

    Previous evidence suggests that exposure to outdoor air pollution during pregnancy could alter fetal metabolic function, which could increase the risk of obesity in childhood. However, to our knowledge, no epidemiologic study has investigated the association between prenatal exposure to air pollution and indicators of fetal metabolic function. We investigated the association between maternal exposure to nitrogen dioxide and fine particulate matter (aerodynamic diameter ≤2.5 µm) and umbilical cord blood leptin and adiponectin levels with mixed-effects linear regression models among 1,257 mother-infant pairs from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, conducted in Canada (2008-2011). We observed that an interquartile-range increase in average exposure to fine particulate matter (3.2 µg/m(3)) during pregnancy was associated with an 11% (95% confidence interval: 4, 17) increase in adiponectin levels. We also observed 13% (95% confidence interval: 6, 20) higher adiponectin levels per interquartile-range increase in average exposure to nitrogen dioxide (13.6 parts per billion) during pregnancy. Significant associations were seen between air pollution markers and cord blood leptin levels in models that adjusted for birth weight z score but not in models that did not adjust for birth weight z score. The roles of prenatal exposure to air pollution and fetal metabolic function in the potential development of childhood obesity should be further explored.

  13. Traffic, air pollution, minority and socio-economic status: addressing inequities in exposure and risk.

    PubMed

    Pratt, Gregory C; Vadali, Monika L; Kvale, Dorian L; Ellickson, Kristie M

    2015-05-19

    Higher levels of nearby traffic increase exposure to air pollution and adversely affect health outcomes. Populations with lower socio-economic status (SES) are particularly vulnerable to stressors like air pollution. We investigated cumulative exposures and risks from traffic and from MNRiskS-modeled air pollution in multiple source categories across demographic groups. Exposures and risks, especially from on-road sources, were higher than the mean for minorities and low SES populations and lower than the mean for white and high SES populations. Owning multiple vehicles and driving alone were linked to lower household exposures and risks. Those not owning a vehicle and walking or using transit had higher household exposures and risks. These results confirm for our study location that populations on the lower end of the socio-economic spectrum and minorities are disproportionately exposed to traffic and air pollution and at higher risk for adverse health outcomes. A major source of disparities appears to be the transportation infrastructure. Those outside the urban core had lower risks but drove more, while those living nearer the urban core tended to drive less but had higher exposures and risks from on-road sources. We suggest policy considerations for addressing these inequities.

  14. Traffic, Air Pollution, Minority and Socio-Economic Status: Addressing Inequities in Exposure and Risk

    PubMed Central

    Pratt, Gregory C.; Vadali, Monika L.; Kvale, Dorian L.; Ellickson, Kristie M.

    2015-01-01

    Higher levels of nearby traffic increase exposure to air pollution and adversely affect health outcomes. Populations with lower socio-economic status (SES) are particularly vulnerable to stressors like air pollution. We investigated cumulative exposures and risks from traffic and from MNRiskS-modeled air pollution in multiple source categories across demographic groups. Exposures and risks, especially from on-road sources, were higher than the mean for minorities and low SES populations and lower than the mean for white and high SES populations. Owning multiple vehicles and driving alone were linked to lower household exposures and risks. Those not owning a vehicle and walking or using transit had higher household exposures and risks. These results confirm for our study location that populations on the lower end of the socio-economic spectrum and minorities are disproportionately exposed to traffic and air pollution and at higher risk for adverse health outcomes. A major source of disparities appears to be the transportation infrastructure. Those outside the urban core had lower risks but drove more, while those living nearer the urban core tended to drive less but had higher exposures and risks from on-road sources. We suggest policy considerations for addressing these inequities. PMID:25996888

  15. [Applying temporally-adjusted land use regression models to estimate ambient air pollution exposure during pregnancy].

    PubMed

    Zhang, Y J; Xue, F X; Bai, Z P

    2017-03-06

    The impact of maternal air pollution exposure on offspring health has received much attention. Precise and feasible exposure estimation is particularly important for clarifying exposure-response relationships and reducing heterogeneity among studies. Temporally-adjusted land use regression (LUR) models are exposure assessment methods developed in recent years that have the advantage of having high spatial-temporal resolution. Studies on the health effects of outdoor air pollution exposure during pregnancy have been increasingly carried out using this model. In China, research applying LUR models was done mostly at the model construction stage, and findings from related epidemiological studies were rarely reported. In this paper, the sources of heterogeneity and research progress of meta-analysis research on the associations between air pollution and adverse pregnancy outcomes were analyzed. The methods of the characteristics of temporally-adjusted LUR models were introduced. The current epidemiological studies on adverse pregnancy outcomes that applied this model were systematically summarized. Recommendations for the development and application of LUR models in China are presented. This will encourage the implementation of more valid exposure predictions during pregnancy in large-scale epidemiological studies on the health effects of air pollution in China.

  16. Non-destructive testing for combined stresses using high-resolution thermal infrared remote sensing and ''three-temperature model'': A case study on mangrove plant Kandelia obovata

    NASA Astrophysics Data System (ADS)

    Shen, X.; LI, R.; Li, Y. H.; Chai, M. W.; Qiu, G. Y.

    2015-12-01

    Mangrove forests are currently facing serious heavy metal pollution and eutrophication problems. Remote sensing of vegetation is a non-invasive methodology to monitor physiological characteristics of plants. The potential of high-resolution thermal infrared remote sensing and the three-temperature model (3T model) for monitoring the effects of combined stresses on mangrove plant Kandelia obovata was assessed. The experiment consists of four levels of CdCl2 stress (0, 1, 5 and 10 mg·L-1) in each of four NH4Cl stress levels: 0, 10, 50 and 100 mg·L-1, respectively. The non-destructive testing indices, including plant transpiration transfer coefficient (hat) and estimated instant transpiration rate, were calculated from thermal images and the 3T model. The photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) were also tested to validate the results of non-destructive testing. The results showed that: (1) The plant transpiration transfer coefficients (hat) were changed from 0.246 to 0.928 and the estimated instant transpiration rates ranged from 0.590 to 6.119 mmol H2O m-2s-1 among different combined stresses. With increasing stress, there were significant decreases for estimated instant transpiration rate and increases for hat (P < 0.05). (2) The photosynthetic characteristics, including Pn, Gs and Tr, were significantly decreased with the increasing combined stresses (P < 0.05). (3) The effects of Cd, N, and their interaction on non-destructive indices and photosynthetic parameters were significant (P < 0.05). (4) The hat was significantly negatively correlated with photosynthetic parameters and the T-3T was significantly positively correlated with photosynthetic parameters (P < 0.05). Therefore, the transpiration transfer coefficient (hat) andestimated instant transpiration rate detecting by infrared thermography device could be indicators to reflect the stress conditions. Based on high-resolution thermal infrared remote sensing, we

  17. Exposure and measurement contributions to estimates of acute air pollution effects.

    PubMed

    Sheppard, Lianne; Slaughter, James C; Schildcrout, Jonathan; Liu, L-J Sally; Lumley, Thomas

    2005-07-01

    Air pollution health effect studies are intended to estimate the effect of a pollutant on a health outcome. The definition of this effect depends upon the study design, disease model parameterization, and the type of analysis. Further limitations are imposed by the nature of exposure and our ability to measure it. We define a plausible exposure model for air pollutants that are relatively nonreactive and discuss how exposure varies. We discuss plausible disease models and show how their parameterizations are affected by different exposure partitions and by different study designs. We then discuss a measurement model conditional on ambient concentrations and incorporate this into the disease model. We use simulation studies to show the impact of a range of exposure model assumptions on estimation of the health effect in the ecologic time series design. This design only uses information from the time-varying ambient source exposure. When ambient and nonambient sources are independent, exposure variation due to nonambient source exposures behaves like Berkson measurement error and does not bias the effect estimates. Variation in the population attenuation of ambient concentrations over time does bias the estimates with the bias being either positive or negative depending upon the association of this parameter with ambient pollution. It is not realistic to substitute measured average personal exposures into time series studies because so much of the variation in personal exposures comes from nonambient sources that do not contribute information in the time series design. We conclude that general statements about the implications of measurement error need to be conditioned on the health effect study design and the health effect parameter to be estimated.

  18. PM2.5 exposure in highly polluted cities: A case study from New Delhi, India.

    PubMed

    Pant, Pallavi; Habib, Gazala; Marshall, Julian D; Peltier, Richard E

    2017-07-01

    Personal exposure (PE) to air pollutants is driven by a combination of pollutant concentrations in indoor and outdoor environments, and time-activity pattern of individuals. The objectives of this study were to estimate personal exposure to PM2.5 and black carbon (BC), and assess the representability of ambient air quality monitoring stations to serve as surrogates for PE in New Delhi. Personal exposure to air pollutants (PM2.5-PE and BCPE) was measured using portable, battery-operated instruments (PM2.5- pDR1500 and BC- microAethalometer AE51) in a small cohort of healthy adults (n=12 in summer, n=6 in winter) with no occupational exposure. Average PM2.5-PE and BCPE (µg/m(3)) were 53.9±136 and 3.71±4.29 respectively, in summer and 489.2±209.2 and 23.3±14.9 respectively, in winter. Activities associated with highest exposure levels were cooking and indoor cleaning for PM2.5, and commuting for BC. Within transport microenvironments, autorickshaws were found to be the most polluted, and lowest BC exposure was registered in public buses. Comparison of fixed-site ambient monitoring data showed a higher correlation with personal exposure dataset in winter compared to summer (r(2) of 0.51 (winter) and 0.21 (summer); 51% (winter) and 20% (summer)). This study highlights the need for detailed assessment of PE to air pollutants in Indian cities, and calls for a denser network of monitoring stations for better exposure assessment. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Gene expression network analyses in response to air pollution exposures in the trucking industry.

    PubMed

    Chu, Jen-Hwa; Hart, Jaime E; Chhabra, Divya; Garshick, Eric; Raby, Benjamin A; Laden, Francine

    2016-11-03

    Exposure to air pollution, including traffic-related pollutants, has been associated with a variety of adverse health outcomes, including increased cardiopulmonary morbidity and mortality, and increased lung cancer risk. To better understand the cellular responses induced by air pollution exposures, we performed genome-wide gene expression microarray analysis using whole blood RNA sampled at three time-points across the work weeks of 63 non-smoking employees at 10 trucking terminals in the northeastern US. We defined genes and gene networks that were differentially activated in response to PM2.5 (particulate matter ≤ 2.5 microns in diameter) and elemental carbon (EC) and organic carbon (OC). Multiple transcripts were strongly associated (padj < 0.001) with pollutant levels (48, 260, and 49 transcripts for EC, OC, and PM2.5, respectively), including 63 that were statistically significantly correlated with at least two out of the three exposures. These genes included many that have been implicated in ischemic heart disease, chronic obstructive pulmonary disease (COPD), lung cancer, and other pollution-related illnesses. Through the combination of Gene Set Enrichment Analysis and network analysis (using GeneMANIA), we identified a core set of 25 interrelated genes that were common to all three exposure measures and were differentially expressed in two previous studies assessing gene expression attributable to air pollution. Many of these are members of fundamental cancer-related pathways, including those related to DNA and metal binding, and regulation of apoptosis and also but include genes implicated in chronic heart and lung diseases. These data provide a molecular link between the associations of air pollution exposures with health effects.

  20. Reduced exposure to air pollution on the boardwalk in Dublin, Ireland. Measurement and prediction.

    PubMed

    McNabola, A; Broderick, B M; Gill, L W

    2008-01-01

    This paper outlines an air pollution study carried out on Dublin city's recently completed boardwalk along the side of and overhanging the River Liffey. Air quality samples were taken along the length of the boardwalk to investigate whether pedestrians using the boardwalk would have a lower air pollution exposure than those using the adjoining footpath along the road. The results of the study show significant reductions in pedestrian exposure to both traffic derived particulates and hydrocarbons along the boardwalk as opposed to the footpath. Computational fluid dynamics was also used to model the outcome of these field measurements and shows the importance of the boundary wall between the footpath and boardwalk in reducing air pollution exposure for the pedestrian, the results of which are also presented herein.