WorldWideScience

Sample records for atmosphere exposure analysis

  1. Atmospheric Dispersion Modelling and Spatial Analysis to Evaluate Population Exposure to Pesticides from Farming Processes

    Directory of Open Access Journals (Sweden)

    Sofia Costanzini

    2018-01-01

    Full Text Available This work originates from an epidemiological study aimed to assess the correlation between population exposure to pesticides used in agriculture and adverse health effects. In support of the population exposure evaluation two models implemented by the authors were applied: a GIS-based proximity model and the CAREA atmospheric dispersion model. In this work, the results of the two models are presented and compared. Despite the proximity analysis is widely used for these kinds of studies, it was investigated how meteorology could affect the exposure assessment. Both models were applied to pesticides emitted by 1519 agricultural fields and considering 2584 receptors distributed over an area of 8430 km2. CAREA output shows a considerable enhancement in the percentage of exposed receptors, from the 4% of the proximity model to the 54% of the CAREA model. Moreover, the spatial analysis of the results on a specific test site showed that the effects of meteorology considered by CAREA led to an anisotropic exposure distribution that differs considerably from the symmetric distribution resulting by the proximity model. In addition, the results of a field campaign for the definition and planning of ground measurement of concentration for the validation of CAREA are presented. The preliminary results showed how, during treatments, pesticide concentrations distant from the fields are significantly higher than background values.

  2. Comprehensive default methodology for the analysis of exposures to mixtures of chemicals accidentally released to the atmosphere

    International Nuclear Information System (INIS)

    Craig, D.K.; Baskett, R.L.; Powell, T.J.; Davis, J.S.; Dukes, L.L.; Hansen, D.J.; Petrocchi, A.J.; Sutherland, P.J.

    1997-01-01

    Safety analysis of Department of Energy (DOE) facilities requires consideration of potential exposures to mixtures of chemicals released to the atmosphere. Exposure to chemical mixtures may lead to additive, synergistic, or antagonistic health effects. In the past, the consequences of each chemical have been analyzed separately. This approach may not adequately protect the health of persons exposed to mixtures. However, considerable time would be required to evaluate all possible mixtures. The objective of this paper is to present reasonable default methodology developed by the EFCOG Safety Analysis Working Group Nonradiological Hazardous Material Subgroup (NHMS) for use in safety analysis within the DOE Complex

  3. Atmospheric Ionizing Radiation and Human Exposure

    Science.gov (United States)

    Wilson, John W.; Mertens, Christopher J.; Goldhagen, Paul; Friedberg, W.; DeAngelis, G.; Clem, J. M.; Copeland, K.; Bidasaria, H. B.

    2005-01-01

    Atmospheric ionizing radiation is of interest, apart from its main concern of aircraft exposures, because it is a principal source of human exposure to radiations with high linear energy transfer (LET). The ionizing radiations of the lower atmosphere near the Earth s surface tend to be dominated by the terrestrial radioisotopes. especially along the coastal plain and interior low lands, and have only minor contributions from neutrons (11 percent). The world average is substantially larger but the high altitude cities especially have substantial contributions from neutrons (25 to 45 percent). Understanding the world distribution of neutron exposures requires an improved understanding of the latitudinal, longitudinal, altitude and spectral distribution that depends on local terrain and time. These issues are being investigated in a combined experimental and theoretical program. This paper will give an overview of human exposures and describe the development of improved environmental models.

  4. Atmospheric Ionizing Radiation and Human Exposure

    Science.gov (United States)

    Wilson, J. W.; Goldhagen, P.; Friedberg, W.; DeAngelis, G.; Clem, J. M.; Copeland, K.; Bidasaria, H. B.

    2004-01-01

    Atmospheric ionizing radiation is of interest, apart from its main concern of aircraft exposures, because it is a principal source of human exposure to radiations with high linear energy transfer (LET). The ionizing radiations of the lower atmosphere near the Earth s surface tend to be dominated by the terrestrial radioisotopes especially along the coastal plain and interior low lands and have only minor contributions from neutrons (11 percent). The world average is substantially larger but the high altitude cities especially have substantial contributions from neutrons (25 to 45 percent). Understanding the world distribution of neutron exposures requires an improved understanding of the latitudinal, longitudinal, altitude and spectral distribution that depends on local terrain and time. These issues are being investigated in a combined experimental and theoretical program. This paper will give an overview of human exposures and describe the development of improved environmental models.

  5. Copper patinas formed in different atmospheres and exposure times

    International Nuclear Information System (INIS)

    Lobo, V.M.M.; Almeida, M.E.; Balmayor, M.; Tomas, H.M.L.R.

    1998-01-01

    Atmospheric corrosion products in copper samples, known as patinas, formed in industrial-marine, severe-marine and rural atmospheres exposed for 1,2,3, and 4 years, have been studied. The nature and structure of the products formed, characterized by X-ray diffraction (XRD) and infrared spectrometry (FTIR) depend on the time of exposure and the type of atmosphere. Copper patinas have been extensively mentioned in the literature, but the structural nature of their compounds, which vary according to the time of exposure and types of atmospheres, is still not adequately described in the literature. In order to give a contribution to this area, copper panels were exposed for 1,2,3, and 4 years in different types of atmospheres representing situations commonly observed, and subsequently the patinas were studied by XRD and FTIR 150 mm x 1 mm copper panels from commercial copper were exposed to three different atmospheric conditions in Portugal: industrial-marine (Leixoes, near Oporto, highly industrialized city close to the Ocean, subject to SO 2 from refineries); rural (Pego, small village in rural environment). The panels, attached to the appropriate stands, in accordance with ISO 8565 (1), were exposed for periods of 1,2,3 and 4 years, adequately collected for laboratory analysis by infrared spectrometry (FTIR). (Author)

  6. Timescale Correlation between Marine Atmospheric Exposure and Accelerated Corrosion Testing

    Science.gov (United States)

    Montgomery, Eliza L.; Calle, Luz Marina; Curran, Jerone C.; Kolody, Mark R.

    2011-01-01

    Evaluation of metal-based structures has long relied on atmospheric exposure test sites to determine corrosion resistance in marine environments. Traditional accelerated corrosion testing relies on mimicking the exposure conditions, often incorporating salt spray and ultraviolet (UV) radiation, and exposing the metal to continuous or cyclic conditions of the corrosive environment. Their success for correlation to atmospheric exposure is often a concern when determining the timescale to which the accelerated tests can be related. Accelerated laboratory testing, which often focuses on the electrochemical reactions that occur during corrosion conditions, has yet to be universally accepted as a useful tool in predicting the long term service life of a metal despite its ability to rapidly induce corrosion. Although visual and mass loss methods of evaluating corrosion are the standard and their use is imperative, a method that correlates timescales from atmospheric exposure to accelerated testing would be very valuable. This work uses surface chemistry to interpret the chemical changes occurring on low carbon steel during atmospheric and accelerated corrosion conditions with the objective of finding a correlation between its accelerated and long-term corrosion performance. The current results of correlating data from marine atmospheric exposure conditions at the Kennedy Space Center beachside corrosion test site, alternating seawater spray, and immersion in typical electrochemical laboratory conditions, will be presented. Key words: atmospheric exposure, accelerated corrosion testing, alternating seawater spray, marine, correlation, seawater, carbon steel, long-term corrosion performance prediction, X-ray photoelectron spectroscopy.

  7. Generation and characterization of gasoline engine exhaust inhalation exposure atmospheres.

    Science.gov (United States)

    McDonald, Jacob D; Barr, Edward B; White, Richard K; Kracko, Dean; Chow, Judith C; Zielinska, Barbara; Grosjean, Eric

    2008-10-01

    Exposure atmospheres for a rodent inhalation toxicology study were generated from the exhaust of a 4.3-L gasoline engine coupled to a dynamometer and operated on an adapted California Unified Driving Cycle. Exposure levels were maintained at three different dilution rates. One chamber at the lowest dilution had particles removed by filtration. Each exposure atmosphere was characterized for particle mass, particle number, particle size distribution, and detailed chemical speciation. The majority of the mass in the exposure atmospheres was gaseous carbon monoxide, nitrogen oxides, and volatile organics, with small amounts of particle-bound carbon/ions and metals. The atmospheres varied according to the cycle, with the largest spikes in volatile organic and inorganic species shown during the "cold start" portion of the cycle. Ammonia present from the exhaust and rodents interacted with the gasoline exhaust to form secondary inorganic particles, and an increase in exhaust resulted in higher proportions of secondary inorganics as a portion of the total particle mass. Particle size had a median of 10-20 nm by number and approximately 150 nm by mass. Volatile organics matched the composition of the fuel, with large proportions of aliphatic and aromatic hydrocarbons coupled to low amounts of oxygenated organics. A new measurement technique revealed organics reacting with nitrogen oxides have likely resulted in measurement bias in previous studies of combustion emissions. Identified and measured particle organic species accounted for about 10% of total organic particle mass and were mostly aliphatic acids and polycyclic aromatic hydrocarbons.

  8. ATMOSPHERIC DISPERSION COEFFICIENTS AND RADIOLOGICAL AND TOXICOLOGICAL EXPOSURE METHODOLOGY FOR USE IN TANK FARMS

    Energy Technology Data Exchange (ETDEWEB)

    GRIGSBY KM

    2011-04-07

    This report presents the atmospheric dispersion coefficients used in Tank Farms safety analysis. The basis equations for calculating radiological and toxicological exposures are also included. In this revision, the time averaging for toxicological consequence evaluations is clarified based on a review of DOE complex guidance and a review of tank farm chemicals.

  9. Exposures to atmospheric effects in the entertainment industry.

    Science.gov (United States)

    Teschke, Kay; Chow, Yat; van Netten, Chris; Varughese, Sunil; Kennedy, Susan M; Brauer, Michael

    2005-05-01

    Theatrical fogs are commonly used in the entertainment industry to create special atmospheric effects during filming and live productions. We examined exposures to mineral oil-and glycol-based theatrical fogs to determine what fluids and effects were commonly used, to measure the size distributions of the aerosols, and to identify factors associated with personal exposure levels. In nonperformance jobs in a range of production types (television, film, live theater, and concerts),we measured airborne concentrations of inhalable aerosol,aldehydes, and polycyclic aromatic hydrocarbons, and collected observations about the sites and tasks performed. Both mineral oil and glycols were observed in use on about one-half the production days in the study. The most common effect produced was a generalized haze over the entire set. Mean personal inhalable aerosol concentrations were 0.70 mg/m3(range 0.02 to 4.1). The mean proportion of total aerosol mass less than 3.5 microns in aerodynamic diameter was 61%. Exposures were higher when mineral oils, rather than glycols, were used to generate fogs. Higher exposures were also associated with movie and television productions, with using more than one fog machine, with increased time spent in visible fog, and for those employed as "grips." Decreased exposures were associated with increasing room temperature, with increasing distance from fog machines, and for those employed as "sound technicians." Exposures to theatrical fogs are just beginning to be measured. It is important to consider these exposures in light of any health effects observed, since existing occupational exposure limits were developed in other industries where the aerosol composition differs from that of theatrical fogs.

  10. Elemental analysis of atmospheric aerosols in Gaborone

    African Journals Online (AJOL)

    ELO

    amount more than 90% were copper, lead, nickel and gold. Key words: Atmospheric particles, elements, ... Selebi-Phikwe area, gold and nickel in Francis town and soda ash in Sowa. Gaborone is the capital of ... a stub three times a week with an exposure time of four hours. The exposed stubs were collected and kept ...

  11. Exposure to the atmospheric ionizing radiation environment: a study on Italian civilian aviation flight personnel

    International Nuclear Information System (INIS)

    De Angelis, G.; Caldora, M.; Santaquilani, M.; Scipione, R.; Verdecchia, A.

    2003-01-01

    A study of the effects of high-LET, low-dose and low-dose-rate ionizing radiation and associated risk analysis is underway. This study involves analyzing the atmospheric ionizing radiation exposure (including high-energy neutrons) and associated effects for members of civilian aviation flight personnel, in an attempt to better understand low-dose long-term radiation effects on human subjects. The study population includes all Italian civilian airline flight personnel, both cockpit and cabin crew members, whose work history records and actual flights (route, aircraft type, and date for each individual flight for each person where possible) are available. The dose calculations are performed along specific flight legs, taking into account the actual flight profiles for all different routes and the variations with time of solar and geomagnetic parameters. Dose values for each flight are applied to the flight history of study participants in order to estimate the individual annual and lifetime occupational radiation dose. An update of the study of the physical atmospheric ionizing radiation exposure is given here, in terms of environmental modeling, flight routes, radiation dose evaluation along different flight paths, and exposure matrix construction. The exposure analysis is still in progress, and the first results are expected soon

  12. [Atmospheric Polybrominated Diphenyl Ethers in Eight Cities of China: Pollution Characteristics and Human Exposure].

    Science.gov (United States)

    Lin, Hai-tao; Li, Qi-lu; Zhang, Gan; Li, Jun

    2016-01-15

    The gas and particle samples of eight cities were collected by high flow active air sampler in the Eastern and Western China and eight congeners of polybrominated diphenyl ethers were analyzed. The results showed that the concentration of BDE-28 (tri-BDE) in the gas-phase (three bromide components) was the highest, which was different from previous studies where BDE-99 and-47 were the predominant homologues in the gas-phase while the concentration of BDE-209 [(25.4 ± 124) pg · m⁻³] in particle-phase was the highest. The atmospheric concentrations of PBDEs in Beijing and Guangzhou were relatively higher, especially the BDE-209 concentration in particle phases of Guangzhou was two orders higher than those of other cities. However, the atmospheric concentrations of PBDEs declined significantly when compared with the data from previous studies. Meanwhile, the results indicated that the gas-phase concentrations decreased slowly and the particle-phase concentrations decreased rapidly. Combined with the results of correlation analysis, this phenomenon might be ascribed to the ceased commercial production of penta- and octa-BDE, the light degradation of high bromide components and reduced concentrations of atmospheric particles in urban area. Inhalation exposure for infants was about 2-3 times higher than that of adults. This reflected that the potential health risk of atmospheric PBDEs in city for residents, especially infants and young children, should not be ignored.

  13. Atmospheric Data Package for the Composite Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Napier, Bruce A.; Ramsdell, James V.

    2005-09-01

    The purpose of this data package is to summarize our conceptual understanding of atmospheric transport and deposition, describe how this understanding will be simplified for numerical simulation as part of the Composite Analysis (i.e., implementation model), and finally to provide the input parameters needed for the simulations.

  14. Analysis of atmospheric particulate samples via instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Greenberg, R.R.

    1990-01-01

    Instrumental neutron activation analysis (INAA) is a powerful analytical technique for the elemental characterization of atmospheric particulate samples. It is a true multielement technique with adequate sensitivity to determine 30 to 40 elements in a sample of atmospheric particulate material. Its nondestructive nature allows sample reanalysis by the same or a different analytical technique. In this paper as an example of the applicability of INAA to the study of atmospheric particulate material, a study of the emissions from municipal incinerators is described

  15. Radiation exposure of airline crew members to the atmospheric ionizing radiation environment

    International Nuclear Information System (INIS)

    Angelis, G. De; Ballard, T.; Lagorio, S.; Verdecchia, A.

    2000-01-01

    All risk assessment techniques for possible health effects from low dose rate radiation exposure should combine knowledge both of the radiation environment and of the biological response, whose effects (e.g. carcinogenesis) are usually evaluated through mathematical models and/or animal and cell experiments. Data on human exposure to low dose rate radiation exposure and its effects are not readily available, especially with regards to stochastic effects, related to carcinogenesis and therefore to cancer risks, for which the event probability increases with increasing radiation exposure. The largest source of such data might be airline flight personnel, if enrolled for studies on health effects induced by the cosmic-ray generated atmospheric ionizing radiation, whose total dose, increasing over the years, might cause delayed radiation-induced health effects, with the high-LET and highly ionizing neutron component typical of atmospheric radiation. In 1990 flight personnel has been given the status of 'occupationally exposed to radiation' by the International Commission for Radiation Protection (ICRP), with a received radiation dose that is at least twice larger than that of the general population. The studies performed until now were limited in scope and cohort size, and moreover no information whatsoever on radiation occupational exposure (e.g. dose, flight hours, route haul, etc.) was used in the analysis, so no correlation has been until now possible between atmospheric ionizing radiation and (possibly radiation-induced) observed health effects. Our study addresses the issues, by considering all Italian civilian airline flight personnel, both cockpit and cabin crew members, with about 10,000 people selected, whose records on work history and actual flights (route, aircraft type, date, etc. for each individual flight for each person where possible) are considered. Data on actual flight routes and profiles have been obtained for the whole time frame. The actual dose

  16. Germination of fungal conidia after exposure to low concentration ozone atmospheres.

    Science.gov (United States)

    The germinability of conidia of Alternaria alternata, Aspergillus flavus, Aspergillus niger, Penicillium digitatum, Penicillium expansum, or Penicillium italicum was determined periodically during exposure for approximately 100 days to a humid atmosphere of air alone or air containing 150 ppb ozone ...

  17. Application of PIXE analysis to atmospheric environmental studies

    International Nuclear Information System (INIS)

    Kasahara, Mikio

    1997-01-01

    Physical and chemical properties of the atmospheric aerosols is a fundamental to understand the behavior of aerosols in the atmosphere. The analysis of atmospheric aerosols is the most preferable fields of the PIXE. In this paper, the characteristics of atmospheric aerosols are reviewed at first, and the sampling method of atmospheric aerosols for the PIXE samples and the characterization of atmospheric aerosols using the PIXE analysis are discussed. (author)

  18. ATMOSPHERIC DISPERSION COEFFICIENTS & RADIOLOGICAL & TOXICOLOGICAL EXPOSURE METHODOLOGY FOR USE IN TANK FARMS

    Energy Technology Data Exchange (ETDEWEB)

    SANDGREN, K.R.

    2005-03-03

    This report presents the atmospheric dispersion coefficients used in Tank Farm safety analyses. The current revision also includes atmospheric dispersion coefficients used for analyses of the Demonstration Bulk Vitrification System. The basic equations for calculating radiological and toxicological exposures are also included.

  19. Neutron activation analysis of atmospheric aerosol

    International Nuclear Information System (INIS)

    Obrusnik, I.

    1986-01-01

    Neutron activation analysis (NAA) is a modern analytical method well suited for the analysis of atmospheric aerosols. Particular steps of the NAA procedure and especially different types of aerosol sampling and sample preparation for analysis are discussed in detail. Several possible NAA techniques are described and the advantages of a purely instrumental technique with short and long irradiation are pointed out. Important performance characteristics of the NAA method such as precision, accuracy, sensitivity and detection limits are also discussed. Different applications of NAA in environmental studies are reviewed. (author)

  20. Atmospheric conditions important for the assessment of population exposure

    International Nuclear Information System (INIS)

    Vidic, S.

    2005-01-01

    Atmospheric distribution of a pollutant can be predicted using numerical weather prediction models and atmospheric dispersion models. The first provides prediction on the evaluation of the meteorological fields for specified time period and the second uses this information to determine the evolution of the dispersing cloud in time and space. There is a number of conditions and features that limit the performance of both models, as they contain a degree of parametrisation that may be a source of error. This paper discusses influential parameters and conditions.(author)

  1. Atmospheric pollutants monitoring by analysis of epiphytic lichens

    International Nuclear Information System (INIS)

    Fuga, Alessandra; Saiki, Mitiko; Marcelli, Marcelo P.; Saldiva, Paulo H.N.

    2008-01-01

    The Canoparmelia texana epiphytic lichenized fungi was used to monitor atmospheric pollution in the Sao Paulo metropolitan region, SP, Brazil. The cluster analysis applied to the element concentration values confirmed the site groups of different levels of pollution due to industrial and vehicular emissions. In the distribution maps of element concentrations, higher concentrations of Ba and Mn were observed in the vicinity of industries and of a petrochemical complex. The highest concentration of Co found in lichens from the Sao Miguel Paulista site is due to the emissions from a metallurgical processing plant that produces this element. For Br and Zn, the highest concentrations could be associated both to vehicular and industrial emissions. Exploratory analyses revealed that the accumulation of toxic elements in C. texana may be of use in evaluating the human risk of cardiopulmonary mortality due to prolonged exposure to ambient levels of air pollution. - Canoparmelia texana lichenized fungi is a valuable biomonitor for atmospheric pollution

  2. Mass spectroscopic analysis of atmospheric particulate matter

    International Nuclear Information System (INIS)

    Wippel, R.

    1997-02-01

    Particulate matter (PM) in the atmosphere vary greatly in origin, in their physical and chemical properties and their effects on climate, atmospheric chemistry and health. Aerosol particles with an aerodynamic diameter less than two μm can enter the respiratory tract of humans when inhaled. Bulk analysis of ambient dust particles was performed using an inductively coupled plasma mass spectrometer (ICP-MS). The size-fractionated collected samples were analyzed after a leaching procedure that simulates the solution reactions occurring in the lungs. A disadvantage of bulk analysis is that it gives no information about the distribution of a certain element within the particles under investigation. A Laser-Microprobe-Mass-Analyzer (LAMMA-500) was used to obtain this information. At sampling sites in Austria and in Zimbabwe, Africa, single particles were sampled using a self-made impactor. One of the final aims in environmental analysis is to successfully apply receptor models that relate the chemical and physical properties of a receptor site to a source. The knowledge of the sources of atmospheric particulate matter is essential for environmental policy makers as well as for epidemiological studies. Artificial neural networks (ANN) have a remarkable ability to handle LAMMA-data. Three ANNs were used as a pattern recognition tool for LAMMA mass spectral data: a back-propagation net, a Kohonen network,and a counter-propagation net. Standard source profiles from the United States Environmental Protection Agency were used as training and test data of the different nets. The elemental patterns of the sum of 100 mass spectra of fine dust particles were presented to the trained nets and satisfactory recognition (> 80 %) was obtained. (author)

  3. Control of occupational exposure to cosmic radiation outside the atmosphere

    International Nuclear Information System (INIS)

    Katoh, Kazuaki; Kaneko, Masahito

    2000-01-01

    Japan is participating in the project of constructing ISS, International Space Station, and taking part of constructing JEM, Japan Experimental Module. It is expected that people working in this module upon completion should be controlled their exposure to cosmic radiation according to Japanese laws. Hence, the issue has been studied by a committee in NASDA, National Space Development Agency of Japan. In 1999, its interim report was released and public comments had been invited. In this presentation, following the introduction of the gist of the interim report as well as comments by the authors, countermeasures are proposed. (author)

  4. Sampling of Atmospheric Precipitation and Deposits for Analysis of Atmospheric Pollution

    OpenAIRE

    Skarżyńska, K.; Polkowska, Ż; Namieśnik, J.

    2006-01-01

    This paper reviews techniques and equipment for collecting precipitation samples from the atmosphere (fog and cloud water) and from atmospheric deposits (dew, hoarfrost, and rime) that are suitable for the evaluation of atmospheric pollution. It discusses the storage and preparation of samples for analysis and also presents bibliographic information on the concentration ranges of inorganic and organic compounds in the precipitation and atmospheric deposit samples.

  5. Atmospheric dispersion and individual exposure of hazardous materials

    International Nuclear Information System (INIS)

    Efthimiou, G.C.; Bartzis, J.G.

    2011-01-01

    In this work a new approach for CFD RANS modelling of dispersion of airborne point source releases is presented. The key feature of this approach is the model capability to predict concentration time scales that are functions not only of the flow turbulence scales but also of the pollutant travel time. This approach has been implemented for the calculation of the concentration fluctuation dissipation time scale and the maximum individual exposure at short time intervals. For the estimation of travel time in the Eulerian grid the new 'radioactive tracer method' is introduced. The new approaches were incorporated in the CFD code ADREA. The capabilities of the new approaches are validated against the Mock Urban Setting Trial field experiment data under neutral conditions. The comparisons of model and observations gave quite satisfactory results.

  6. Characterization of corrosion products formed on steels in the first months of atmospheric exposure

    OpenAIRE

    Antunes Renato Altobelli; Costa Isolda; Faria Dalva Lúcia Araújo de

    2003-01-01

    The corrosion products of carbon steel and weathering steel exposed to three different types of atmospheres, at times ranging from one to three months, have been identified. The steels were exposed in an industrial site, an urban site (São Paulo City, Brazil), and a humid site. The effect of the steel type on the corrosion products formed in the early stages of atmospheric corrosion has been evaluated. The corrosion products formed at the various exposure locations were characterized by Raman...

  7. Timescale Correlation between Marine Atmospheric Exposure and Accelerated Corrosion Testing - Part 2

    Science.gov (United States)

    Montgomery, Eliza L.; Calle, Luz Marina; Curran, Jerome C.; Kolody, Mark R.

    2012-01-01

    Evaluation of metals to predict service life of metal-based structures in corrosive environments has long relied on atmospheric exposure test sites. Traditional accelerated corrosion testing relies on mimicking the exposure conditions, often incorporating salt spray and ultraviolet (UV) radiation, and exposing the metal to continuous or cyclic conditions similar to those of the corrosive environment. Their reliability to correlate to atmospheric exposure test results is often a concern when determining the timescale to which the accelerated tests can be related. Accelerated corrosion testing has yet to be universally accepted as a useful tool in predicting the long-term service life of a metal, despite its ability to rapidly induce corrosion. Although visual and mass loss methods of evaluating corrosion are the standard, and their use is crucial, a method that correlates timescales from accelerated testing to atmospheric exposure would be very valuable. This paper presents work that began with the characterization of the atmospheric environment at the Kennedy Space Center (KSC) Beachside Corrosion Test Site. The chemical changes that occur on low carbon steel, during atmospheric and accelerated corrosion conditions, were investigated using surface chemistry analytical methods. The corrosion rates and behaviors of panels subjected to long-term and accelerated corrosion conditions, involving neutral salt fog and alternating seawater spray, were compared to identify possible timescale correlations between accelerated and long-term corrosion performance. The results, as well as preliminary findings on the correlation investigation, are presented.

  8. Global emission inventory and atmospheric transport of black carbon. Evaluation of the associated exposure

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rong

    2015-06-01

    This thesis presents research focusing on the improvement of high-resolution global black carbon (BC) emission inventory and application in assessing the population exposure to ambient BC. A particular focus of the thesis is on the construction of a high-resolution (both spatial and sectorial) fuel consumption database, which is used to develop the emission inventory of black carbon. Above all, the author updates the global emission inventory of black carbon, a resource subsequently used to study the atmospheric transport of black carbon over Asia with the help of a high-resolution nested model. The thesis demonstrates that spatial bias in fuel consumption and BC emissions can be reduced by means of the sub-national disaggregation approach. Using the inventory and nested model, ambient BC concentrations can be better validated against observations. Lastly, it provides a complete uncertainty analysis of global black carbon emissions, and this uncertainty is taken into account in the atmospheric modeling, helping to better understand the role of black carbon in regional and global air pollution.

  9. Study of atmospheric tritium transfers in lettuce: kinetic study, equilibrium and organic incorporation during a continuous atmospheric exposure

    International Nuclear Information System (INIS)

    Boyer, C.

    2009-01-01

    This thesis has explored the mechanisms of tritium 'absorption and incorporation in a human-consumed plant, lettuce (Lactuca sativa L.), due to atmospheric exposure. Foliar uptake appears to play a key role in absorption of tritium as tissue free water tritium. Whatever the development stage and the light conditions, the specific activity in tissue free water reaches that of water vapour in air in several hours. The specific activity ratio is then about 0, 4. The time to reach equilibrium in soil is over 24 hours in most cases: the specific activity ratio ranges then 0, 01 to 0, 26. Incorporation rate of tissue free water tritium as organically-bound tritium has been estimated to 0, 13 to 0, 16 % h-l in average over the growing period of the plant, but marked variations are observed during growth. In particular, a significant increase appeared at the exponential growth stage. Deposition and diffusion of tritium in soil lead to significant OBT activities in soil. Results globally indicate equilibrium between the different environmental compartments (air, soil, plant). However, some experiments have revealed high OBT concentrations regarding atmospheric level exposure and ask for a possible phenomenon of local tritium accumulation in OBT for particular conditions of exposure. (author) [fr

  10. Radiation exposure of airline crew members to the atmospheric ionizing radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    De Angelis, G. E-mail: gianni.deangelis@iol.it; Caldora, M.; Santaquilani, M.; Scipione, R.; Verdecchia, A

    2001-06-01

    A study of radiation exposures in the ionizing radiation environment of the atmosphere is currently in progress for the Italian civil aviation flight personnel. After a description of the considered data sources/ the philosophy of the study is presented/ and an overview is given of the data processing with regard to flight routes/ the computational techniques for radiation dose evaluation along the flight paths and for the exposure matrix building/ along with an indication of the results that the study should provide.

  11. An overview of organically bound tritium experiments in plants following a short atmospheric HTO exposure.

    Science.gov (United States)

    Galeriu, D; Melintescu, A; Strack, S; Atarashi-Andoh, M; Kim, S B

    2013-04-01

    The need for a less conservative, but reliable risk assessment of accidental tritium releases is emphasized in the present debate on the nuclear energy future. The development of a standard conceptual model for accidental tritium releases must be based on the process level analysis and the appropriate experimental database. Tritium transfer from atmosphere to plants and the subsequent conversion into organically bound tritium (OBT) strongly depends on the plant characteristics, seasons, and meteorological conditions, which have a large variability. The present study presents an overview of the relevant experimental data for the short term exposure, including the unpublished information, also. Plenty of experimental data is provided for wheat, rice, and soybean and some for potato, bean, cherry tomato, radish, cabbage, and tangerine as well. Tritiated water (HTO) uptake by plants during the daytime and nighttime has an important role in further OBT synthesis. OBT formation in crops depends on the development stage, length, and condition of exposure. OBT translocation to the edible plant parts differs between the crops analyzed. OBT formation during the nighttime is comparable with that during the daytime. The present study is a preliminary step for the development of a robust model of crop contamination after an HTO accidental release. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Analysis of monoterpene hydrocarbons in rural atmospheres

    International Nuclear Information System (INIS)

    Holdren, M.W.; Westberg, H.H.; Zimmerman, P.R.

    1979-01-01

    Gas chromatographic/mass spectrometric analysis of monoterpenes from a rural forested site in the northwestern United States is described. Use of a glass capillary column provided excellent resolution of the hydrocarbons. Increased sensitivity and specificity of the mass spectrometer detector over the flame ionization detector were demonstrated for trace (parts per trillion) atmospheric hydrocarbons. As little as 10 ppt of compound was detectable in 100-cc air samples. Two analytical methods (cryogenic and solid adsorbent--Tenax-GC) were used in the collection of ambient air. Analytical results from the two techniques compared very well. Rural concentrations of the monoterpenes varied considerably depending upon location within the forest canopy. The concentration of individual species never exceeded 1 ppb of compound during a 10-month sampling period. The monoterpene total for all samples fell in the range of 0.5- to 16-ppb compound for C 10 terpene

  13. The multimedia models for the evaluation of exposure bond to the atmospheric emissions of classified installations

    International Nuclear Information System (INIS)

    Bonnard, R.

    2001-12-01

    Risk assessment and environmental impacts studies are realized to preserve the public health. Today one of the most used approach is the use of an atmospheric dispersion model to assess the risks. The data are then injected in a calculation software of exposure bond to polluted soils, to evaluate the risks of non direct exposure. This report details and evaluates the models corresponding to the need: the methodology for assessing Health Risks associated with multiple pathways of exposure to combustor, human health risk assessment proto col for hazardous waste combustion facilities, EUSES, CALTOX, MEPAS, MEND-TOX, RESRAD, MMSOILS, FRAMES-HWIR, PC-GEMS and TRIM. (A.L.B.)

  14. ATMOSPHERIC DISPERSION COEFFICIENTS & RADIOLOGICAL & TOXICOLOGICAL EXPOSURE METHODOLOGY FOR USE IN TANK FARMS

    Energy Technology Data Exchange (ETDEWEB)

    COWLEY, W.L.

    2005-01-31

    This report presents the atmospheric dispersion coefficients used for Tank Farms safety analyses. The report also contains the necessary documentation for meeting Software QA requirements for the GXQ software. The basic equations for calculating radiological doses and chemical exposures are also included. Revision 3 adds information about Building Wakes and calculates dispersion coefficients that incorporate building wake for 222-S and 242-A.

  15. Atmospheric Environment Vulnerability Cause Analysis for the Beijing-Tianjin-Hebei Metropolitan Region.

    Science.gov (United States)

    Zhang, Yang; Shen, Jing; Li, Yu

    2018-01-13

    Assessing and quantifying atmospheric vulnerability is a key issue in urban environmental protection and management. This paper integrated the Analytical hierarchy process (AHP), fuzzy synthesis evaluation and Geographic Information System (GIS) spatial analysis into an Exposure-Sensitivity-Adaptive capacity (ESA) framework to quantitatively assess atmospheric environment vulnerability in the Beijing-Tianjin-Hebei (BTH) region with spatial and temporal comparisons. The elaboration of the relationships between atmospheric environment vulnerability and indices of exposure, sensitivity, and adaptive capacity supports enable analysis of the atmospheric environment vulnerability. Our findings indicate that the atmospheric environment vulnerability of 13 cities in the BTH region exhibits obvious spatial heterogeneity, which is caused by regional diversity in exposure, sensitivity, and adaptive capacity indices. The results of atmospheric environment vulnerability assessment and the cause analysis can provide guidance to pick out key control regions and recognize vulnerable indicators for study sites. The framework developed in this paper can also be replicated at different spatial and temporal scales using context-specific datasets to support environmental management.

  16. Analysis on the atmospheric dispersion of radioactive materials

    International Nuclear Information System (INIS)

    Nagai, Haruyasu

    2012-01-01

    JAEA has been developing a new prediction system of comprehensive movement, SPEEDI-MP (SPEEDI Multi-model Package), which can treat continuously and strictly with the migration behavior of radioactive materials at atmosphere, sea, and land region. JAEA has been further promoting the detail analysis of atmospheric migration of radioactive materials dispersed by an accident. Then, using a part of this system, the atmospheric-diversion prediction system, WSPEEDI-II, the atmospheric diversion mass and the atmospheric diffusion analysis were carried out. This issue reports the summary. (M.H.)

  17. Effect of corrosive marine atmosphere on construction materials in Tanzania: Exposure sites and preliminary results

    International Nuclear Information System (INIS)

    Mmari, A.G.; Uiso, C.B.S.; Makundi, I.N.; Potgieter-Vermaak, S.S.; Potgieter, J.H.; Van Grieken, R.

    2007-01-01

    Air pollution studies in Africa are limited and the influence of ambient air quality on buildings and constructions have not been investigated in the larger part of Sub-Saharan Africa. The increasing burden of emission from industry, traffic and coal power plants on ambient air pollution in Sub-Saharan Africa necessitated reviewing previous and current studies. In South Africa a 20-year exposure program, focusing on the effect of ambient exposure on various metals and alloys, showed that the amount of rainfall, relative humidity, atmospheric pollution, wind speed, solar radiation and structural design are some of the factors controlling atmospheric corrosion. Tanzania, being among the Sub-Saharan African countries and partly bordered by Indian ocean, the main source of marine atmosphere, experiences corrosive degradation on metal roofing and cementitious materials. This paper describes the exposure site set-up and will report on some preliminary results of air quality and its relation with the meteorological conditions, as well as surface changes observed, for the year one of exposure. These will thereafter be compared to the completed European and Asian studies, as reported by CLRTAP and RAPIDC respectively. (author)

  18. Cost benefit analysis for occupational radiation exposure

    International Nuclear Information System (INIS)

    Caruthers, G.F.; Rodgers, R.C.; Donohue, J.P.; Swartz, H.M.

    1978-01-01

    In the course of system design, many decisions must be made concerning different aspects of that particular system. The design of systems and components in a nuclear power plant has the added faction of occupational exposure experienced as a result of that design. This paper will deal with the different methods available to factor occupational exposure into design decisions. The ultimate goal is to have exposures related to the design 'As Low As Reasonably Achievable' or ALARA. To do this an analysis should be performed to show that the cost of reducing exposures any further cannot be justified in a cost-benefit analysis. In this paper examples will be given that will show that it is possible to change to a design which would increase occupational exposure somewhat but would increase the benefit over the cost of the extra exposure received. It will also be shown that some changes in design or additional equipment could be justified due to a reduction in exposure while some changes could not be justified on a reduction in exposure aspect alone but are justified on a time saving aspect such as during a refueling outage. (author)

  19. AXAIR: A Computer Code for SAR Assessment of Plume-Exposure Doses from Potential Process-Accident Releases to Atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pillinger, W.L.

    2001-05-17

    This report describes the AXAIR computer code which is available to terminal users for evaluating the doses to man from exposure to the atmospheric plume from postulated stack or building-vent releases at the Savannah River Plant. The emphasis herein is on documentation of the methodology only. The total-body doses evaluated are those that would be exceeded only 0.5 percent of the time based on worst-sector, worst-case meteorological probability analysis. The associated doses to other body organs are given in the dose breakdowns by radionuclide, body organ and pathway.

  20. Air exposure of coral is a significant source of dimethylsulfide (DMS) to the atmosphere.

    Science.gov (United States)

    Hopkins, Frances E; Bell, Thomas G; Yang, Mingxi; Suggett, David J; Steinke, Michael

    2016-10-31

    Corals are prolific producers of dimethylsulfoniopropionate (DMSP). High atmospheric concentrations of the DMSP breakdown product dimethylsulfide (DMS) have been linked to coral reefs during low tides. DMS is a potentially key sulfur source to the tropical atmosphere, but DMS emission from corals during tidal exposure is not well quantified. Here we show that gas phase DMS concentrations (DMS gas ) increased by an order of magnitude when three Indo-Pacific corals were exposed to air in laboratory experiments. Upon re-submersion, an additional rapid rise in DMS gas was observed, reflecting increased production by the coral and/or dissolution of DMS-rich mucus formed by the coral during air exposure. Depletion in DMS following re-submersion was likely due to biologically-driven conversion of DMS to dimethylsulfoxide (DMSO). Fast Repetition Rate fluorometry showed downregulated photosynthesis during air exposure but rapid recovery upon re-submersion, suggesting that DMS enhances coral tolerance to oxidative stress during a process that can induce photoinhibition. We estimate that DMS emission from exposed coral reefs may be comparable in magnitude to emissions from other marine DMS hotspots. Coral DMS emission likely comprises a regular and significant source of sulfur to the tropical marine atmosphere, which is currently unrecognised in global DMS emission estimates and Earth System Models.

  1. Is atmospheric pollution exposure during pregnancy associated with individual and contextual characteristics? A nationwide study in France.

    Science.gov (United States)

    Ouidir, Marion; Lepeule, Johanna; Siroux, Valérie; Malherbe, Laure; Meleux, Frederik; Rivière, Emmanuel; Launay, Ludivine; Zaros, Cécile; Cheminat, Marie; Charles, Marie-Aline; Slama, Rémy

    2017-10-01

    Exposure to atmospheric pollutants is a danger for the health of pregnant mother and children. Our objective was to identify individual (socioeconomic and behavioural) and contextual factors associated with atmospheric pollution pregnancy exposure at the nationwide level. Among 14 921 women from the French nationwide ELFE (French Longitudinal Study of Children) mother-child cohort recruited in 2011, outdoor exposure levels of PM 2.5 , PM 10 (particulate matter atmospheric pollutants with individual (maternal age, body mass index, parity, education level, relationship status, smoking status) and contextual (European Deprivation Index, urbanisation level) factors. Patterns of associations were globally similar across pollutants. For the CART approach, the highest tertile of exposure included mainly women not in a relationship living in urban and socially deprived areas, with lower education level. Linear regression models identified different determinants of atmospheric pollutants exposure according to the residential urbanisation level. In urban areas, atmospheric pollutants exposure increased with social deprivation, while in rural areas a U-shaped relationship was observed. We highlighted social inequalities in atmospheric pollutants exposure according to contextual characteristics such as urbanisation level and social deprivation and also according to individual characteristics such as education, being in a relationship and smoking status. In French urban areas, pregnant women from the most deprived neighbourhoods were those most exposed to health-threatening atmospheric pollutants. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  2. Light Emission Requires Exposure to the Atmosphere in Ex Vivo Bioluminescence Imaging

    Directory of Open Access Journals (Sweden)

    Yusuke Inoue

    2006-04-01

    Full Text Available The identification of organs bearing luciferase activity by in vivo bioluminescence imaging (BLI is often difficult, and ex vivo imaging of excised organs plays a complementary role. This study investigated the importance of exposure to the atmosphere in ex vivo BLI. Mice were inoculated with murine pro-B cell line Ba/F3 transduced with firefly luciferase and p190 BCR-ABL. They were killed following in vivo BLI, and whole-body imaging was done after death and then after intraperitoneal air injection. In addition, the right knee was exposed and imaged before and after the adjacent bones were cut. Extensive light signals were seen on in vivo imaging. The luminescence disappeared after the animal was killed, and air injection restored the light emission from the abdomen only, suggesting a critical role of atmospheric oxygen in luminescence after death. Although no substantial light signal at the right knee was seen before bone cutting, light emission was evident after cutting. In conclusion, in ex vivo BLI, light emission requires exposure to the atmosphere. Bone destruction is required to demonstrate luciferase activity in the bone marrow after death.

  3. The effects of air pollution and climatic factors on atmospheric corrosion of marble under field exposure

    International Nuclear Information System (INIS)

    Lan, Tran Thi Ngoc; Nishimura, Rokuro; Tsujino, Yoshio; Satoh, Yukihiro; Thi Phuong Thoa, Nguyen; Yokoi, Masayuki; Maeda, Yasuaki

    2005-01-01

    The atmospheric corrosion of marble was evaluated in terms of SO 2 concentration as air pollution and climatic factors such as rainfall, relative humidity, temperature and so on under the field exposure. Marble of calcite type (CaCO 3 ) was exposed to outdoor atmospheric environment with and without a rain shelter at four test sites in the southern part of Vietnam for 3-month, 1- and 2-year periods from July 2001 to September 2003. The thickness loss of marble was investigated gravimetrically. X-ray diffraction and X-ray fluorescent methods were applied to study corrosion products on marble. The corrosion product of marble was only gypsum (CaSO 4 . 2H 2 O) and was washed out by rain under the unsheltered exposure condition. It was found that the most substantial factors influencing the corrosion of marble were rainfall, SO 2 concentration in the air and relative humidity. Based on the results obtained, we estimated the dose-response functions for the atmospheric corrosion of marble in the southern part of Vietnam

  4. Laser spectroscopic analysis in atmospheric pollution research

    CSIR Research Space (South Africa)

    Forbes, PBC

    2008-01-01

    Full Text Available stream_source_info ForbesP_2008.pdf.txt stream_content_type text/plain stream_size 3174 Content-Encoding ISO-8859-1 stream_name ForbesP_2008.pdf.txt Content-Type text/plain; charset=ISO-8859-1 Laser spectroscopic... Department and a CSIR National Laser Centre rental pool programme grant-holder, is involved in research into a novel method of monitoring atmospheric PAHs. The rental pool programme gives South African tertiary education institutions access to an array...

  5. Kinetics of atmospheric corrosion of mild steel, zinc, galvanized iron and aluminium at 10 exposure stations in India

    International Nuclear Information System (INIS)

    Natesan, M.; Venkatachari, G.; Palaniswamy, N.

    2006-01-01

    As a part of updating Corrosion Map of India project, atmospheric corrosion behaviour of commercially available engineering materials such as mild steel, galvanized iron, zinc and aluminium metals was studied in marine, industrial, urban, and rural environments by weight loss method at 10 exposure stations in India over a period of 5 years. The results of these studies demonstrated that galvanized iron, zinc and aluminium metals were several times more durable than mild steel. Compared to galvanized iron and zinc, aluminium provided superior protection in industrial and marine environment except at Mormugao Port Trust (MPT). It also offered much better resistance to corrosion in rural environments. At certain places, galvanized iron proved to be more durable than aluminium. The results obeyed well with the empirical kinetics equation of the form C = Kt n , where K and C are the corrosion losses in μm after 1 and 't' years of the exposure, respectively, and 'n' is a constant. Based on 'n' values, the corrosion mechanisms of these metals are predicted. The corrosion products formed on the metal samples in Chennai marine atmosphere were identified by X-ray diffraction analysis

  6. SHORT-TERM EXPOSURE TO ATMOSPHERIC AMMONIA DOES NOT AFFECT LOW-TEMPERATURE HARDENING OF WINTER-WHEAT

    NARCIS (Netherlands)

    CLEMENT, JMAM; VENEMA, JH; VANHASSELT, PR

    The effect of atmospheric NH3 on low-temperature hardening of winter wheat (Triticum aestivum L. cv. Urban) was investigated. Growth and photosynthesis were stimulated by ammonia exposure. After a 14 d exposure at moderate temperatures (day/night 18.5/16 degrees C) total nitrogen content was

  7. PIXE analysis: an option for the study of atmospheric pollutants

    International Nuclear Information System (INIS)

    Aldape, U.F.

    1989-01-01

    Several techniques have been utilized in studying atmospheric contamination samples. However, each lack some characteristics required for these studies. Spectroscopy of X-rays particularly where excitation models are produced using charged particles (Particle Induced X-ray Emission, PIXE), for its high sensitivity, is the one that best fitting itself to the scheme of analysis required. In this paper we report some qualitative results of the atmospheric aerosol samples collected in Mexico City. (Author)

  8. Neutron activation analysis of atmospheric aerosols

    International Nuclear Information System (INIS)

    Riekstinya, D.V.; Mednis, I.V.; Veveris, O.Eh.

    1987-01-01

    A review of studies by Soviet and foreign authors on radioactivation analysis is presented. Instrumental neutron activation analysis (INAA) techniques have been developed providing the possibility to determine a number of elements in very small portions of aerosols for pollutanless areas of the Earth. Two ways of INAA are presented: with long- and short-living radionuclides. The Antarctic and the Indian Ocean aerosol samples have been analysed for 26 microelements. It has been stated that restrictions of the detection limits attained relate to high proportions of certain elements and their nonhomogeneous distribution in filters. The detection limits can be lowered by the filtered air volume growth per unit of the filter area

  9. Multitaper spectral analysis of atmospheric radar signals

    Directory of Open Access Journals (Sweden)

    V. K. Anandan

    2004-11-01

    Full Text Available Multitaper spectral analysis using sinusoidal taper has been carried out on the backscattered signals received from the troposphere and lower stratosphere by the Gadanki Mesosphere-Stratosphere-Troposphere (MST radar under various conditions of the signal-to-noise ratio. Comparison of study is made with sinusoidal taper of the order of three and single tapers of Hanning and rectangular tapers, to understand the relative merits of processing under the scheme. Power spectra plots show that echoes are better identified in the case of multitaper estimation, especially in the region of a weak signal-to-noise ratio. Further analysis is carried out to obtain three lower order moments from three estimation techniques. The results show that multitaper analysis gives a better signal-to-noise ratio or higher detectability. The spectral analysis through multitaper and single tapers is subjected to study of consistency in measurements. Results show that the multitaper estimate is better consistent in Doppler measurements compared to single taper estimates. Doppler width measurements with different approaches were studied and the results show that the estimation was better in the multitaper technique in terms of temporal resolution and estimation accuracy.

  10. Studies on tritium incorporation into wheat plants after short-term exposure to atmospheric tritium

    International Nuclear Information System (INIS)

    Diabate, S.; Strack, S.; Raskob, W.

    1996-01-01

    The paper summarizes the results of a series of laboratory experiments to study the uptake, loss, conversion and translocation of tritium in wheat plants following a short-term exposure to atmospheric tritiated water vapour (HTO) under laboratory conditions. The experiments were accompanied by the development of a Plant-OBT-Model to calculate the tritium behaviour in wheat. Exposures of potted plants were carried out between anthesis and maturity, under day conditions at two different light intensities (900 μmol m -2 s -1 and 120 μmol m -2 s -1 photosynthetic active radiation) and under night conditions. In leaves, the tritium uptake into tissue water tritium (TWT) was about four times lower under night conditions than day conditions. Organically bound tritium (OBT) was generated in leaves, stems and ears under day as well as under night conditions. The initial relative OBT concentrations in leaves observed under night conditions were about 50% of those under day conditions. OBT was translocated into the grain in dependence on the growth rate of the grain. Due to incorporation of new organic matter with lower OBT concentration into the grain, the specific OBT concentrations decreased slightly until harvest but the total OBT was rather constant. Once translocation to grain has taken place, OBT is lost only slowly. The growth of the plants has been calibrated with the measured growth data of winter wheat and spring wheat. Subsequently, the tritium incorporation was calibrated using the results of the exposure experiments in the same year. The final OBT concentration in the grain can be predicted with sufficient precision. However, the modelling of the OBT formation and turnover processes right after exposure to tritium needs improvement. A comprehensive validation of the model with independent data sets is still necessary. (J.P.N.)

  11. [Prolonged exposure to atmospheric air pollution and mortality from respiratory causes].

    Science.gov (United States)

    Eilstein, D

    2009-12-01

    Different designs can be used to analyze the relationships between respiratory mortality and long term exposure to atmospheric pollution: epidemiological studies (cohort, prevalence study) demonstrate the reality of the relationship and toxicological studies explain it. Cohort studies have the advantage of being able to take into account many confounding factors and thus avoid biases (which is not the case with prevalence studies), but require significant human and financial resources. They were first adopted in the US, but are now more often applied in Europe. The results are relatively consistent, as they all show a statistically significant association between an increase in particulate pollution and cardiopulmonary mortality. Mortality from lung cancer is also associated with long term exposition to particles and sometimes to ozone or nitrogen oxides. Cerebrovascular diseases and sudden death of young children have also been associated with particulate pollution. The relationships are more powerful for long term than short term exposure but are also linear and without threshold. In order to explain these effects (today the causality of the relationship is certain) there are many possible factors, particularly regarding particulate exposures: an increase in cardiovascular risk biomarkers (fibrinogen, white blood cells, and platelets), atherosclerosis, chronic inflammation of lung tissues increased by acute exposure, etc. More and more studies address the interaction between gene and environment and even epigenetic phenomena which could be responsible of these effects. Public Health impact could be quantified. The European E&H surveillance program Apheis, for example, estimated that if PM2.5 levels remained below 15 microg/m(3), a 30 year old person could see his life expectancy increased by 1 month to 2 years, depending on the studied city. Finally, mortality is not the only relevant indicator for health effects of air pollution. ISAAC studies address asthma

  12. Fetal cocaine exposure: analysis of vernix caseosa.

    Science.gov (United States)

    Moore, C; Dempsey, D; Deitermann, D; Lewis, D; Leikin, J

    1996-10-01

    Preliminary data regarding the use of vernix caseosa (VC) as an alternative to other biological specimens for the determination of fetal cocaine exposure are presented. Advantages of VC analysis include its presence on all newborn babies, historical record of drug exposure, and ease of collection and storage. Fifteen samples of vernix caseosa-five from babies known to be cocaine-exposed because of a positive benzoylecgonine result from the urine and umbilical cord blood and ten from nonexposed neonates-were analyzed for the presence of cocaine and metabolites. VC samples from three of the five neonates known to be cocaine-exposed were positive for cocaine or its metabolites, the other two had little or no remaining specimen. The remaining ten were negative.

  13. Health effects from exposure to atmospheric mineral dust near Las Vegas, NV, USA

    Directory of Open Access Journals (Sweden)

    Deborah E. Keil

    Full Text Available Desert areas are usually characterized by a continuous deposition of fine airborne particles. Over time, this process results in the accumulation of silt and clay on desert surfaces. We evaluated health effects associated with regional atmospheric dust, or geogenic dust, deposited on surfaces in the Nellis Dunes Recreation Area (NDRA in Clark County, Nevada, a popular off-road vehicle (ORV recreational site frequented daily by riders, families, and day campers. Because of atmospheric mixing and the mostly regional origin of the accumulated particles, the re-suspended airborne dust is composed of a complex mixture of minerals and metals including aluminum, vanadium, chromium, manganese, iron, cobalt, copper, zinc, arsenic, strontium, cesium, lead, uranium, and others. Geogenic dust with a median diameter of 4.1 μm was administered via oropharyngeal aspiration to female B6C3F1 mice at doses of 0.01 to 100 mg dust/kg body weight, four times, a week apart, for 28-days. Immuno- and neurotoxicological outcomes 24 h following the last exposure were evaluated. Antigen-specific IgM responses were dose-responsively suppressed at 0.1, 1.0, 10 and 100 mg/kg/day. Splenic and thymic lymphocytic subpopulations and natural killer cell activity also were significantly reduced. Antibodies against MBP, NF-68, and GFAP were not affected, while brain CD3+ T cells were decreased in number. A lowest observed adverse effect level (LOAEL of 0.1 mg/kg/day and a no observed adverse effect level (NOAEL of 0.01 mg/kg/day were derived based on the antigen-specific IgM responses. Keywords: Geogenic dust, Heavy metals, Minerals, Lung exposure, Immunotoxicity, Neurotoxicity

  14. Yttrium and lanthanides in human lung fluids, probing the exposure to atmospheric fallout

    Energy Technology Data Exchange (ETDEWEB)

    Censi, P., E-mail: censi@unipa.it [Dipartimento C.F.T.A., Universita di Palermo, Via Archirafi, 36 90123 - Palermo (Italy); I.A.M.C.-CNR - UOS di Capo Granitola, Via faro, 1 - 91026 Torretta Granitola, Campobello di Mazara (TP) (Italy); En.Bio.Tech. - Via Aquileia, 35 90100 Palermo (Italy); Tamburo, E. [Dipartimento C.F.T.A., Universita di Palermo, Via Archirafi, 36 90123 - Palermo (Italy); Speziale, S. [Deutsches GeoForschungsZentrum, Telegrafenberg, Potsdam, 14473 (Germany); Zuddas, P. [Institut Genie de l' Environnement et Ecodeveloppement and Departement Sciences de la Terre, UMR 5125, Universite Claude Bernard Lyon 1, 2 rue R. Dubois, Bat GEODE 69622 Villeurbanne Cedex (France); Randazzo, L.A. [Dipartimento C.F.T.A., Universita di Palermo, Via Archirafi, 36 90123 - Palermo (Italy); I.A.M.C.-CNR - UOS di Capo Granitola, Via faro, 1 - 91026 Torretta Granitola, Campobello di Mazara (TP) (Italy); En.Bio.Tech. - Via Aquileia, 35 90100 Palermo (Italy); Institut Genie de l' Environnement et Ecodeveloppement and Departement Sciences de la Terre, UMR 5125, Universite Claude Bernard Lyon 1, 2 rue R. Dubois, Bat GEODE 69622 Villeurbanne Cedex (France); Punturo, R. [Dipartimento di Scienze Geologiche, Universita di Catania, Corso Italia, 55 - 95129 Catania (Italy); Cuttitta, A. [I.A.M.C.-CNR - UOS di Capo Granitola, Via faro, 1 - 91026 Torretta Granitola, Campobello di Mazara (TP) (Italy); Arico, P. [Dipartimento C.F.T.A., Universita di Palermo, Via Archirafi, 36 90123 - Palermo (Italy)

    2011-02-28

    Inhalation of airborne particles can produce crystallization of phosphatic microcrysts in intraaveolar areas of lungs, sometimes degenerating into pulmonary fibrosis. Results of this study indicate that these pathologies are induced by interactions between lung fluids and inhaled atmospheric dust in people exposed to volcanic dust ejected from Mount Etna in 2001. Here, the lung solid-liquid interaction is evaluated by the distribution of yttrium and lanthanides (YLn) in fluid bronchoalveolar lavages on selected individuals according the classical geochemical approaches. We found that shale-normalised patterns of yttrium and lanthanides have a 'V shaped' feature corresponding to the depletion of elements from Nd to Tb when compared to the variable enrichments of heavy lanthanides, Y, La and Ce. These features and concurrent thermodynamic simulations suggest that phosphate precipitation can occur in lungs due to interactions between volcanic particles and fluids. We propose that patterns of yttrium and lanthanides can represent a viable explanation of some pathology observed in patients after prolonged exposure to atmospheric fallout and are suitable to become a diagnostic parameter of chemical environmental stresses.

  15. The characteristics of atmospheric phthalates in Shanghai: A haze case study and human exposure assessment

    Science.gov (United States)

    Li, Yingjie; Wang, Jiahui; Ren, Bainian; Wang, Hongli; Qiao, Liping; Zhu, Jiping; Li, Li

    2018-04-01

    While phthalates in indoor environments are extensively studied, reports on phthalates in outdoor air, particularly their associations with haze weather events are rare. Phthalates, especially dimethyl phthalate, are known to react with criteria air pollutants contributing to the formation of secondary organic aerosols. This study investigated phthalates levels in the atmosphere in Shanghai with a focus on their associations with different air quality weather events. The air quality during the study period was classified into three levels: non-haze, light pollution and moderate pollution. Phthalates levels were found to be lower in non-haze weather events (236 ng/m3) and higher in moderate pollution weather events (up to 700 ng/m3). Meteorological factors of relative humidity and wind speed had an inverse relationship with phthalates levels. Particulate matter had a positive correlation with phthalates levels. Hydroxyl radical initiated photo-reaction of dimethyl phthalate was evident by its inverse relationship with total atmospheric oxidant (O3 + NO2), indicating that dimethyl phthalate could be one of the precursors of secondary organic aerosol causing haze weather events. Daily intake of phthalates through exposure to outdoor air is estimated to be relatively minor; children intake remains higher on a body weight basis. This is the first study demonstrating the relationship of phthalates and different air quality conditions in haze weather events. The knowledge contributes to our understanding on the cause of haze weather events in China and elsewhere.

  16. High sensitivity analysis of atmospheric gas elements

    International Nuclear Information System (INIS)

    Miwa, Shiro; Nomachi, Ichiro; Kitajima, Hideo

    2006-01-01

    We have investigated the detection limit of H, C and O in Si, GaAs and InP using a Cameca IMS-4f instrument equipped with a modified vacuum system to improve the detection limit with a lower sputtering rate We found that the detection limits for H, O and C are improved by employing a primary ion bombardment before the analysis. Background levels of 1 x 10 17 atoms/cm 3 for H, of 3 x 10 16 atoms/cm 3 for C and of 2 x 10 16 atoms/cm 3 for O could be achieved in silicon with a sputtering rate of 2 nm/s after a primary ion bombardment for 160 h. We also found that the use of a 20 K He cryo-panel near the sample holder was effective for obtaining better detection limits in a shorter time, although the final detection limits using the panel are identical to those achieved without it

  17. High sensitivity analysis of atmospheric gas elements

    Energy Technology Data Exchange (ETDEWEB)

    Miwa, Shiro [Materials Analysis Lab., Sony Corporation, 4-16-1 Okata, Atsugi 243-0021 (Japan)]. E-mail: Shiro.Miwa@jp.sony.com; Nomachi, Ichiro [Materials Analysis Lab., Sony Corporation, 4-16-1 Okata, Atsugi 243-0021 (Japan); Kitajima, Hideo [Nanotechnos Corp., 5-4-30 Nishihashimoto, Sagamihara 229-1131 (Japan)

    2006-07-30

    We have investigated the detection limit of H, C and O in Si, GaAs and InP using a Cameca IMS-4f instrument equipped with a modified vacuum system to improve the detection limit with a lower sputtering rate We found that the detection limits for H, O and C are improved by employing a primary ion bombardment before the analysis. Background levels of 1 x 10{sup 17} atoms/cm{sup 3} for H, of 3 x 10{sup 16} atoms/cm{sup 3} for C and of 2 x 10{sup 16} atoms/cm{sup 3} for O could be achieved in silicon with a sputtering rate of 2 nm/s after a primary ion bombardment for 160 h. We also found that the use of a 20 K He cryo-panel near the sample holder was effective for obtaining better detection limits in a shorter time, although the final detection limits using the panel are identical to those achieved without it.

  18. Atmospheric Pathway Screening Analysis for Saltstone Disposal Facility Vault 4

    International Nuclear Information System (INIS)

    COOK, JAMES

    2004-01-01

    A sequential screening process using a methodology developed by the National Council on Radiation Protection and Measurements, professional judgment and process knowledge has been used to produce a list of radionuclides requiring detailed analysis to derive disposal limits for the Saltstone Disposal Facility based on the atmospheric pathway

  19. Annual Book of ASTM Standards, Part 23: Water; Atmospheric Analysis.

    Science.gov (United States)

    American Society for Testing and Materials, Philadelphia, PA.

    Standards for water and atmospheric analysis are compiled in this segment, Part 23, of the American Society for Testing and Materials (ASTM) annual book of standards. It contains all current formally approved ASTM standard and tentative test methods, definitions, recommended practices, proposed methods, classifications, and specifications. One…

  20. Forecasting human exposure to atmospheric pollutants in Portugal - A modelling approach

    Science.gov (United States)

    Borrego, C.; Sá, E.; Monteiro, A.; Ferreira, J.; Miranda, A. I.

    2009-12-01

    Air pollution has become one main environmental concern because of its known impact on human health. Aiming to inform the population about the air they are breathing, several air quality modelling systems have been developed and tested allowing the assessment and forecast of air pollution ambient levels in many countries. However, every day, an individual is exposed to different concentrations of atmospheric pollutants as he/she moves from and to different outdoor and indoor places (the so-called microenvironments). Therefore, a more efficient way to prevent the population from the health risks caused by air pollution should be based on exposure rather than air concentrations estimations. The objective of the present study is to develop a methodology to forecast the human exposure of the Portuguese population based on the air quality forecasting system available and validated for Portugal since 2005. Besides that, a long-term evaluation of human exposure estimates aims to be obtained using one-year of this forecasting system application. Additionally, a hypothetical 50% emission reduction scenario has been designed and studied as a contribution to study emission reduction strategies impact on human exposure. To estimate the population exposure the forecasting results of the air quality modelling system MM5-CHIMERE have been combined with the population spatial distribution over Portugal and their time-activity patterns, i.e. the fraction of the day time spent in specific indoor and outdoor places. The population characterization concerning age, work, type of occupation and related time spent was obtained from national census and available enquiries performed by the National Institute of Statistics. A daily exposure estimation module has been developed gathering all these data and considering empirical indoor/outdoor relations from literature to calculate the indoor concentrations in each one of the microenvironments considered, namely home, office/school, and other

  1. Applications of stable isotope analysis to atmospheric trace gas budgets

    Directory of Open Access Journals (Sweden)

    Brenninkmeijer C. A.M.

    2009-02-01

    Full Text Available Stable isotope analysis has become established as a useful method for tracing the budgets of atmospheric trace gases and even atmospheric oxygen. Several new developments are briefly discussed in a systematic way to give a practical guide to the scope of recent work. Emphasis is on applications and not on instrumental developments. Processes and reactions are less considered than applications to resolve trace gas budgets. Several new developments are promising and applications hitherto not considered to be possible may allow new uses.

  2. Optimum modellings of atmospheric diffusion of radioactive effluents and exposure doses in the accident consequence assessment (Level 3 PSA)

    International Nuclear Information System (INIS)

    Kim, Byung Woo; Lee, Young Bok; Han, Moon Hee; Kim, Eun Han; Suh, Kyung Suk; Hwang, Won Tae

    1992-12-01

    Atmospheric diffusion and exposure strongly dependent on the environment were firstly considered in the full spectrum of accident consequence assessment to establish based on Korean conditions. An optimum weather category based on Korean climate and site-specific meteorology of Kori region was established by statistical analysis of measured data for 10 years. And a trajectory model was selected as the optimal one in the ACA by reviewing several existing diffusion models. Following aspects were considered in this selection as availability of meteorological data, ability to treat the change to wind direction, easy applicability of the model, and restriction of CPU time and core memory in current computers. Numerical integration method of our own was selected as the optimal dose assessment tool of external exposure. Unit dose rate was firstly computed with this method as the function of energy level of radionuclide, size of lattice, and distance between source and receptor, and then the results were rearranged as the data library for the rapid access to the ACA run. Dynamic ecosystem modelling has been done in order to estimate the seasonal variation of radioactivity for the assessment of ingestion exposure, considering Korean ingestion behavior, agricultural practice and the transportation. There is a lot of uncertainty in a countermeasure model due to the assumed values of parameters such as fraction of population with different shielding factor and driving speed. A new countermeasure model was developed using the concept of fuzzy set theory, since it provided the mathematical tools which could characterize the uncertainty involved in countermeasure modelling. (Author)

  3. Titan atmospheric composition by hypervelocity shock layer analysis

    International Nuclear Information System (INIS)

    Nelson, H.F.; Park, C.; Whiting, E.E.

    1989-01-01

    The Cassini Mission, a NASA/ESA cooperative project which includes a deployment of probe into the atmosphere of Titan, is described, with particular attention given to the shock radiometer experiment planned for the Titan probe for the analysis of Titan's atmosphere. Results from a shock layer analysis are presented, demonstrating that the mole fractions of the major species (N2, CH4, and, possibly Ar) in the Titan atmosphere can be successfully determined by the Titan-probe radiometer, by measuring the intensity of the CN(violet) radiation emitted in the shock layer during the high velocity portion of the probe entry between 200 and 400 km altitude. It is shown that the sensitivity of the CN(violet) radiation makes it possible to determine the mole fractions of N2, CH4, and Ar to about 0.015, 0.003, and 0.01, respectively, i.e., much better than the present uncertainties in the composition of Titan atmosphere. 29 refs

  4. Technical Overview of Ecological Risk Assessment - Analysis Phase: Exposure Characterization

    Science.gov (United States)

    Exposure Characterization is the second major component of the analysis phase of a risk assessment. For a pesticide risk assessment, the exposure characterization describes the potential or actual contact of a pesticide with a plant, animal, or media.

  5. EXPOSURE ANALYSIS MODELING SYSTEM (EXAMS): USER MANUAL AND SYSTEM DOCUMENTATION

    Science.gov (United States)

    The Exposure Analysis Modeling System, first published in 1982 (EPA-600/3-82-023), provides interactive computer software for formulating aquatic ecosystem models and rapidly evaluating the fate, transport, and exposure concentrations of synthetic organic chemicals - pesticides, ...

  6. Analysis of the atmospheric 7Be radioactivity by neural network

    International Nuclear Information System (INIS)

    Moroz, Z.; Myslek-Laurikainen, B.; Matul, M.; Mikolajewski, S.; Preibisz, Z.; Trzaskowaka, H.; Kownacki, C.

    2002-01-01

    Computational methods of artificial intelligence (neural networks) and modern signal processing (wavelet decomposition were applied for the analysis of atmospheric 7 Be radioactivity data. Measurements were performed each week during 1994-2001 in the sampling station placed at Swider Geophysical Observatory. Raw data as well as those averaged over 4 and 10 weeks were used. Ability of the neural networks for the purpose of representation, interpolation and prediction was tested. The corresponding relative errors are calculated. Next, the time sequences were decomposed using the wavelet method and eight components of different time scales were obtained. Neural networks were applied separately to each of those components. Application of such analysis and their possible extensions useful for the construction of phenomeno-logical models of atmospheric radioactivity are discussed. (author)

  7. PIXE analysis of atmospheric aerosol and hydrometeor particles

    International Nuclear Information System (INIS)

    Groeneveld, K.O.; Hofmann, D.; Georgii, H.W.

    1993-01-01

    Atmospheric aerosol and hydrometeor particles act decisively on our weather, climate and thereby on all living conditions on Earth. Particle induced X-ray emission (PIXE) analysis has been demonstrated to be an extremely valuable tool for quantitative and qualitative elemental analysis of aerosol particles and hydrometeors. Reliability and detection limits of PIXE are determined, including comparison with other techniques. Aerosol particles are collected on a global scale in ground stations, or by ships and by planes. Correlation between wind direction and elemental composition of atmospheric aerosols, elemental particle size distributions of the tropospheric aerosol, aerosol elemental composition in particle size fractions in the case of long range transport, transport pathways of pollution aerosol, and trace element content precipitation are discussed. Hydrometeors were studied in the form of rain, snow, fog, dew and frost. The time dependence of the melting process of snow was studied in detail, in particular the washout phenomena of impurity ions. (orig.)

  8. Analysis of tritium releases to the atmosphere by a CTR

    International Nuclear Information System (INIS)

    Renne, D.S.; Sandusky, W.F.; Dana, M.T.

    1975-08-01

    Removal by atmospheric processes of routinely and accidentally released tritium from a controlled thermonuclear reactor (CTR) was investigated. Based on previous studies, the assumed form of the tritium for this analysis was HTO or tritiated water vapor. Assuming a CTR operation in Morris, Illinois, surface water and ground-level air concentration values of tritium were computed for three space (or time) scales: local (50 Km of a plant), regional (up to 1000 Km of the plant), and global

  9. Final safety analysis report for the atmospheric protection system

    International Nuclear Information System (INIS)

    1976-06-01

    An Atmospheric Protection System (APS) has been constructed at the Idaho Chemical Processing Plant to minimize the release of radioactive particulate material to the atmosphere from nonroutine occurrences. Existing off-gas cleanup systems remove radioactive particulates to well below allowable limits for controlled areas before release to the plant stack. Previously all ventilation air from process cells was discharged to the stack without treatment. The APS provides continuous filtration of all ventilation air from process cells and backup filtration of all process off gases before they are released to the atmosphere. A safety analysis of the potential hazards associated with the APS has been completed. The review indicates that the system is capable of withstanding design basis natural phenomena including a flood, tornado, and earthquake without releasing unacceptable amounts of radioactive particulate from the filters to the environment. An in-cell explosion, fire, mechanical damage, and other postulated accident situations were investigated. From these, the design basis accident postulated for the facility is complete release of the maximum amount of radioactive particulate collected on the 104 ventilation air HEPA filters to the atmosphere via the 250-foot high stack. Even though the release of all the radioactive particulate contained on the filters is hardly credible, it would not present an unacceptable hazard to personnel on or offsite

  10. Viking Lander image analysis of Martian atmospheric dust

    Science.gov (United States)

    Pollack, James B.; Ockert-Bell, Maureen E.; Shepard, Michael K.

    1995-01-01

    We have reanalyzed three sets of Viking Lander 1 and 2 (VL1 and VL2) images of the Martian atmosphere to better evaluate the radiative properties of the atmospheric dust particles. The properties of interest are the first two moments of the size distribution, the single-scattering albedo, the dust single-scattering phase function, and the imaginary index of refraction. These properties provide a good definition of the influence that the atmospheric dust has on heating of the atmosphere. Our analysis represents a significant improvement over past analyses (Pollack et al. 1977,1979) by deriving more accurate brightnesses closer to the sun, by carrying out more precise analyses of the data to acquire the quantities of interest, and by using a better representation of scattering by nonspherical particles. The improvements allow us to better define the diffraction peak and hence the size distribution of the particles. For a lognormal particle size distribution, the first two moments of the size distribution, weighted by the geometric cross section, are found. The geometric cross-section weighted mean radius (r(sub eff)) is found to be 1.85 +/- 0.3 microns at VL2 during northern summer when dust loading was low and 1.52 +/- 0.3 microns at VL1 during the first dust storm. In both cases the best cross-section weighted mean variance (nu(eff)) of the size distribution is equal to 0.5 +/- 0.2 microns. The changes in size distribution, and thus radiative properties, do not represent a substantial change in solar energy deposition in the atmosphere over the Pollack et al. (1977,1979) estimates.

  11. Exergy analysis of a crude oil atmospheric distillation unit

    International Nuclear Information System (INIS)

    Rivero, R.; Gonzalez, G.V.; Garcia, V.H.; Pulido, R.; Escarcega, C.A.

    1989-01-01

    This paper deals with the application of an exergy analysis to an existing and operating crude oil atmospheric distillation unit. The objective of such an analysis is to fully understand where energy inefficiencies and real energy losses are located and where modifications should be implemented to improve the overall utilization of energy in the plant. First, the description of the process and the block diagram are presented. After that, the calculating procedure to obtain the exergy balance, the exergy losses, the effectiveness and the improvement potential for each plant component is described and the corresponding results are shown. Finally, the component and overall evaluations are discussed

  12. Multichannel singular spectrum analysis of the axial atmospheric angular momentum

    Directory of Open Access Journals (Sweden)

    Leonid Zotov

    2017-11-01

    Full Text Available Earth's variable rotation is mainly produced by the variability of the AAM (atmospheric angular momentum. In particular, the axial AAM component χ3, which undergoes especially strong variations, induces changes in the Earth's rotation rate. In this study we analysed maps of regional input into the effective axial AAM from 1948 through 2011 from NCEP/NCAR reanalysis. Global zonal circulation patterns related to the LOD (length of day were described. We applied MSSA (Multichannel Singular Spectrum Analysis jointly to the mass and motion components of AAM, which allowed us to extract annual, semiannual, 4-month, quasi-biennial, 5-year, and low-frequency oscillations. PCs (Principal components strongly related to ENSO (El Nino southern oscillation were released. They can be used to study ENSO-induced changes in pressure and wind fields and their coupling to LOD. The PCs describing the trends have captured slow atmospheric circulation changes possibly related to climate variability.

  13. Assessment of exposures to 131I in the continental United States resulting from the Nevada atmospheric nuclear tests

    International Nuclear Information System (INIS)

    Bouville, A.; Wachholz, B.W.; Dreicer, M.

    1991-01-01

    The National Cancer Institute (NCI) is conducting an assessment of the exposure to 131 I that the American people received from the fallout resulting from the atmospheric bomb tests carried out at the Nevada Test Site (NTS). It is estimated that about 5 EBq of 131 I were released into the atmosphere as a result of approximately 100 tests carried out mainly in the 1950s. The most important source of human exposure from fallout 131 I was due to the ingestion of cows' milk but other routes of exposure (ingestion of goats' milk, leafy vegetables, eggs, and cottage cheese as well as inhalation) are also considered. The exposure to 131 I are assessed on a test-by-test and county-by-county basis. In order to make these estimates for locations throughout the United States, it is necessary to determine: The activities of 131 I deposited on soil and vegetation, the amount of 131 I consumed by dairy cows and the resulting 131 I concentrations in cow's milk, and the 131 I ingested by people. The overall methodology currently used in the assessment of the 131 I exposures is presented. Particular attention is devoted to the methodology developed to estimate the intake of contaminated pasture by dairy cows, milk production, and milk distribution for each county of the continental United States during the 1950s

  14. Non-LTE model atmosphere analysis of Nova Cygni 1992

    Science.gov (United States)

    Hauschildt, P. H.; Starrfield, S.; Austin, S.; Wagner, R. M.; Shore, S. N.; Sonneborn, G.

    1994-01-01

    We use spherically symmetric non-local thermodynamic equilibrium (non-LTE), line-blanketed, expanding model atmospheres to analyze the International Ultraviolet Explorer (IUE) and optical spectra of Nova Cygni 1992 during the early phases of its outburst. We find that the first IUE spectrum obtained just after discovery on 1992 February 20, is best reproduced by a model atmosphere with a steep density gradient and homologous expansion, whereas the IUE and optical spectra obtained on February 24 show an extended, optically thick, wind structure. Therefore, we distinguish two phases of the early evolution of the nova photosphere: the initial, rapid, 'fireball' phase and the subsequent, much longer, optically thick 'wind' phase. The importance of line-blanketing in nova spectra is demonstrated. Our preliminary abundance analysis implies that hydrogen is depeleted in the ejecta, corresponding to abundance enhancements of Fe by a factor of approximately 2 and of CNO by more than a factor of 10 when compared to solar abundances. The synthetic spectra reproduce both the observed pseudo-continua as well as most of the observed features from the UV to the optical spectral range and demonstrate the importance of obtaining nearly simultaneous UV and optical spectra for performing accurate analyses of expanding stellar atmospheres (for both novae and supernovae).

  15. Optical monitoring of CH3NH3PbI3 thin films upon atmospheric exposure

    International Nuclear Information System (INIS)

    Ghimire, Kiran; Zhao, Dewei; Cimaroli, Alex; Ke, Weijun; Yan, Yanfa; Podraza, Nikolas J

    2016-01-01

    CH 3 NH 3 PbI 3 perovskite films of interest for photovoltaic (PV) devices have been prepared by (i) vapor deposition and (ii) solution processing. Complex dielectric function ( ε   =   ε 1   +  i ε 2 ) spectra and structural parameters of the films have been extracted using near infrared to ultraviolet spectroscopic ellipsometry. In situ real time spectroscopic ellipsometry (RTSE) over a 48 h period has been performed on vapor deposited CH 3 NH 3 PbI 3 after the deposition in normal atmospheric laboratory ambient conditions. Analysis of RTSE data for vapor deposited CH 3 NH 3 PbI 3 film prepared under un-optimized conditions identifies phase segregated PbI 2 and CH 3 NH 3 I at the substrate/film interface and unreacted PbI 2 and CH 3 NH 3 I on the film surface. This analysis also provides the time dependence of the effective thicknesses of perovskite film, unreacted components, and phase segregated layers to track CH 3 NH 3 PbI 3 decomposition. (paper)

  16. Radiation exposure analysis of female nuclear medicine radiation workers

    International Nuclear Information System (INIS)

    Lee, Ju Young; Park, Hoon Hee

    2016-01-01

    In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus

  17. Radiation exposure analysis of female nuclear medicine radiation workers

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Young [Dept. of Biomedical Engineering Graduate School, Chungbuk National University, Cheongju (Korea, Republic of); Park, Hoon Hee [Dept. of Radiological Technologist, Shingu College, Sungnam (Korea, Republic of)

    2016-06-15

    In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus

  18. Tritium uptake in cultivated plants after short-term exposure to atmospheric tritium

    International Nuclear Information System (INIS)

    Diabate, S.; Strack, S.; Paunescu, N.

    1998-01-01

    The tritium behavior in crop plants is of particular interest for the prediction of doses to humans due to ingestion. Tritium is present in plants in two forms: tritium free water tissue (TWT) and organically bound tritium (OBT). The both forms are to be considered in models calculating the ingestion dose. Potato plants belong to the major food crops in many countries and were chosen as representatives of crops whose edible parts grow under ground. Green bean were chosen as representatives of vegetables relevant in human diet. This vegetable may be consumed as green pod and it may be conserved over a long period of time. Green bean and potato plants were exposed to tritiated water vapor in the atmosphere during their generative phase of development. The uptake of tritium and the conversion into organic matter was studied under laboratory conditions at two different light intensities. The tritium concentrations in plants were followed until harvest. In leaves, the tritium uptake into tissue water under night conditions was 5-6 times lower than under day-time conditions. The initial incorporation into organic matter under night conditions was 0.7% of the tissue water concentration in leaves of both plant species. However, under light irradiation, this value increased to only 1.8% in bean leaves and 0.9% in potato leaves, which indicates a participation of processes other than photosynthesis in tritium incorporation into organic material. Organically bound tritium (OBT) was translocated into pods and tubers which represented a high percentage of the total organically bound tritium at harvest. The behavior of total OBT in all plants under study showed that OBT, once generated, is lost very slowly until harvest, in particular when storage organs of plants were in their phase of development at the time of exposure. OBT is translocated into the storage organs which may be used in the human diet and thus may contribute to the ingestion dose for a long time after the

  19. NASA's Upper Atmosphere Research Program (UARP) and Atmospheric Chemistry Modeling and Analysis Program (ACMAP): Research Summaries 1997-1999

    Science.gov (United States)

    Kurylo, M. J.; DeCola, P. L.; Kaye, J. A.

    2000-01-01

    Under the mandate contained in the FY 1976 NASA Authorization Act, the National Aeronautics and Space Administration (NASA) has developed and is implementing a comprehensive program of research, technology development, and monitoring of the Earth's upper atmosphere, with emphasis on the upper troposphere and stratosphere. This program aims at expanding our chemical and physical understanding to permit both the quantitative analysis of current perturbations as well as the assessment of possible future changes in this important region of our environment. It is carried out jointly by the Upper Atmosphere Research Program (UARP) and the Atmospheric Chemistry Modeling and Analysis Program (ACMAP), both managed within the Research Division in the Office of Earth Science at NASA. Significant contributions to this effort have also been provided by the Atmospheric Effects of Aviation Project (AEAP) of NASA's Office of Aero-Space Technology. The long-term objectives of the present program are to perform research to: understand the physics, chemistry, and transport processes of the upper troposphere and the stratosphere and their control on the distribution of atmospheric chemical species such as ozone; assess possible perturbations to the composition of the atmosphere caused by human activities and natural phenomena (with a specific emphasis on trace gas geographical distributions, sources, and sinks and the role of trace gases in defining the chemical composition of the upper atmosphere); understand the processes affecting the distributions of radiatively active species in the atmosphere, and the importance of chemical-radiative-dynamical feedbacks on the meteorology and climatology of the stratosphere and troposphere; and understand ozone production, loss, and recovery in an atmosphere with increasing abundances of greenhouse gases. The current report is composed of two parts. Part 1 summarizes the objectives, status, and accomplishments of the research tasks supported

  20. A systematic review of secondhand smoke exposure in a car: Attributable changes in atmospheric and biological markers.

    Science.gov (United States)

    Raoof, Sana A; Agaku, Israel T; Vardavas, Constantine I

    2015-05-01

    Exposure to secondhand smoke (SHS) has been linked to disease, disability, and premature death. While several countries have enacted smoke-free legislations, exposure to SHS may still occur in unregulated private environments, such as in the family car. We performed a systematic review of peer-reviewed literature in PubMed and Web of Science up to May 2013. Articles were selected if they provided a quantitative measure of SHS exposure (biological or atmospheric markers); the study was conducted inside a car; and the assessed exposure was attributable to cigarette combustion. From 202 articles identified, 12 met the inclusion criteria. Among all studies that assessed smoking in cars with at least one window partially open, the particulate matter 2.5 μm or less in diameter (PM2.5) concentrations ranged from 47 μg/m(3) to 12,150 μg/m(3). For studies with all windows closed, PM2.5 ranged from 203.6 μg/m(3) to 13,150 μg/m(3). SHS concentration in a car was mediated by air-conditioning status, extent of airflow, and driving speed. Smoking in cars leads to extremely high exposure to SHS and increased concentration of atmospheric markers of exposure-even in the presence of air-conditioning or increased airflow from open windows. This clearly shows that the only way to protect nonsmokers, especially children, from SHS within cars is by eliminating tobacco smoking. © The Author(s) 2015.

  1. Hydrocarbon solvent exposure data: compilation and analysis of the literature.

    Science.gov (United States)

    Caldwell, D J; Armstrong, T W; Barone, N J; Suder, J A; Evans, M J

    2000-01-01

    An occupational exposure database for hydrocarbon solvent end-use applications was constructed from the published literature. The database provides exposure assessment information for such purposes as regulatory risk assessments, support of industry product stewardship initiatives, and identification of applications in which limited exposure data are available. It is quantitative, documented, and based on credible data. Approximately 350 articles containing quantitative hydrocarbon solvent exposure data were identified using a search of computer databases of published literature. Many articles did not report sufficient details of the exposure data for inclusion in the database (e.g., full-shift exposure or task-based exposure data). Others were excluded because only limited summary statistics were provided, which precluded statistical analysis of the data (e.g., arithmetic mean concentration presented, but no sample number). Following evaluation, 16,880 hydrocarbon solvent exposure measurements from 99 articles were entered into a database for analysis. Methods used to identify and evaluate published solvent exposure data are described along with more detailed analysis of worker exposure to hydrocarbon solvents in three major end-use applications: painting and coating, printing, and adhesives. Solvent exposures were evaluated against current ACGIH threshold limit values (TLVs) and trends were identified. Limited quantitative data are available prior to 1970. In general, reported hydrocarbon solvent exposures decreased fourfold from 1960 to 1998, were below the TLVs applicable to specific hydrocarbon solvents at the time, and on average have been below 40% of the TLV since 1980. The database already has proved valuable; however, the utility of published exposure data could be further improved if authors consistently reported essential data elements and supporting information.

  2. A tool model for predicting atmospheric kinetics with sensitivity analysis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A package( a tool model) for program of predicting atmospheric chemical kinetics with sensitivity analysis is presented. The new direct method of calculating the first order sensitivity coefficients using sparse matrix technology to chemical kinetics is included in the tool model, it is only necessary to triangularize the matrix related to the Jacobian matrix of the model equation. The Gear type procedure is used to integrate amodel equation and its coupled auxiliary sensitivity coefficient equations. The FORTRAN subroutines of the model equation, the sensitivity coefficient equations, and their Jacobian analytical expressions are generated automatically from a chemical mechanism. The kinetic representation for the model equation and its sensitivity coefficient equations, and their Jacobian matrix is presented. Various FORTRAN subroutines in packages, such as SLODE, modified MA28, Gear package, with which the program runs in conjunction are recommended.The photo-oxidation of dimethyl disulfide is used for illustration.

  3. Characterization of population exposure to organochlorines: A cluster analysis application

    NARCIS (Netherlands)

    R.M. Guimarães (Raphael Mendonça); S. Asmus (Sven); A. Burdorf (Alex)

    2013-01-01

    textabstractThis study aimed to show the results from a cluster analysis application in the characterization of population exposure to organochlorines through variables related to time and exposure dose. Characteristics of 354 subjects in a population exposed to organochlorine pesticides residues

  4. A micro-fabricated hydrogen storage module with sub-atmospheric activation and durability in air exposure

    Energy Technology Data Exchange (ETDEWEB)

    Shan, Xi; Payer, Joe H. [Corrosion and Reliability Engineering, Department of Chemical and Biomolecular Engineering, University of Akron, 302 Buchtel Common, Akron, OH 44325 (United States); Wainright, Jesse S.; Dudik, Laurie [Department of Chemical Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States)

    2011-01-15

    The objective of this work was to develop a hydrogen storage module for onboard electrical power sources suitable for use in micro-power systems and micro-electro-mechanical systems (MEMS). Hydrogen storage materials were developed as thin-film inks to be compatible with an integrated manufacturing process. Important design aspects were (a) ready activation at sub-atmospheric hydrogen pressure and room temperature and (b) durability, i.e. capable of hundreds of absorption/desorption cycles and resistance to deactivation on exposure to air. Inks with palladium-treated intermetallic hydrogen storage alloys were developed and are shown here to be compatible with a thin-film micro-fabrication process. These hydrogen storage modules absorb hydrogen readily at atmospheric pressure, and the absorption/desorption rates remained fast even after the ink was exposed to air for 47 weeks. (author)

  5. Exposure to nickel by hair mineral analysis.

    Science.gov (United States)

    Michalak, Izabela; Mikulewicz, Marcin; Chojnacka, Katarzyna; Wołowiec, Paulina; Saeid, Agnieszka; Górecki, Henryk

    2012-11-01

    The aim of the present work was to investigate the exposure to nickel from various sources by investigation of mineral composition of human scalp hair. The research was carried out on hair sampled from subjects, including 87 males and 178 females (22 ± 2 years). The samples of hair were analyzed by ICP-OES. The effect of several factors on nickel content in hair was examined: lifestyle habits (e.g. hair coloring, hair spray, hair straighteners, hair drier, drugs); dietary factors (e.g. yoghurts, blue cheese, lettuce, lemon, mushroom, egg, butter); other (e.g. solarium, cigarette smoking, tap water pipes, tinned food, PVC foil, photocopier, amalgam filling). These outcomes were reached by linking the results of nickel level in hair with the results of questionnaire survey. Basing on the results it can be concluded that exposure to nickel ions can occur from different sources: lifestyle, eating habits and environmental exposure. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Applying Authentic Data Analysis in Learning Earth Atmosphere

    Science.gov (United States)

    Johan, H.; Suhandi, A.; Samsudin, A.; Wulan, A. R.

    2017-09-01

    The aim of this research was to develop earth science learning material especially earth atmosphere supported by science research with authentic data analysis to enhance reasoning through. Various earth and space science phenomenon require reasoning. This research used experimental research with one group pre test-post test design. 23 pre-service physics teacher participated in this research. Essay test was conducted to get data about reason ability. Essay test was analyzed quantitatively. Observation sheet was used to capture phenomena during learning process. The results showed that student’s reasoning ability improved from unidentified and no reasoning to evidence based reasoning and inductive/deductive rule-based reasoning. Authentic data was considered using Grid Analysis Display System (GrADS). Visualization from GrADS facilitated students to correlate the concepts and bring out real condition of nature in classroom activity. It also helped student to reason the phenomena related to earth and space science concept. It can be concluded that applying authentic data analysis in learning process can help to enhance students reasoning. This study is expected to help lecture to bring out result of geoscience research in learning process and facilitate student understand concepts.

  7. Desorption atmospheric pressure photoionization high-resolution mass spectrometry: a complementary approach for the chemical analysis of atmospheric aerosols.

    Science.gov (United States)

    Parshintsev, Jevgeni; Vaikkinen, Anu; Lipponen, Katriina; Vrkoslav, Vladimir; Cvačka, Josef; Kostiainen, Risto; Kotiaho, Tapio; Hartonen, Kari; Riekkola, Marja-Liisa; Kauppila, Tiina J

    2015-07-15

    On-line chemical characterization methods of atmospheric aerosols are essential to increase our understanding of physicochemical processes in the atmosphere, and to study biosphere-atmosphere interactions. Several techniques, including aerosol mass spectrometry, are nowadays available, but they all suffer from some disadvantages. In this research, desorption atmospheric pressure photoionization high-resolution (Orbitrap) mass spectrometry (DAPPI-HRMS) is introduced as a complementary technique for the fast analysis of aerosol chemical composition without the need for sample preparation. Atmospheric aerosols from city air were collected on a filter, desorbed in a DAPPI source with a hot stream of toluene and nitrogen, and ionized using a vacuum ultraviolet lamp at atmospheric pressure. To study the applicability of the technique for ambient aerosol analysis, several samples were collected onto filters and analyzed, with the focus being on selected organic acids. To compare the DAPPI-HRMS data with results obtained by an established method, each filter sample was divided into two equal parts, and the second half of the filter was extracted and analyzed by liquid chromatography/mass spectrometry (LC/MS). The DAPPI results agreed with the measured aerosol particle number. In addition to the targeted acids, the LC/MS and DAPPI-HRMS methods were found to detect different compounds, thus providing complementary information about the aerosol samples. DAPPI-HRMS showed several important oxidation products of terpenes, and numerous compounds were tentatively identified. Thanks to the soft ionization, high mass resolution, fast analysis, simplicity and on-line applicability, the proposed methodology has high potential in the field of atmospheric research. Copyright © 2015 John Wiley & Sons, Ltd.

  8. Improved conductivity of ZnO thin films by exposure to an atmospheric hydrogen plasma

    NARCIS (Netherlands)

    Illiberi, A.; Kniknie, B.; Deelen, J. van; Steijvers, H.L.A.H.; Habets, D.; Simons, P.J.P.M.; Janssen, A.C.; Beckers, E.H.A.

    2012-01-01

    Aluminum-doped zinc oxide (ZnOx:Al) films have been deposited on a moving glass substrate by a high throughput metalorganic chemical vapor deposition process at atmospheric pressure. Thin (< 250 nm) ZnOx:Al films have a poor crystalline quality, due to a small grain size and the presence of

  9. Analysis of medical exposures in digital mammography

    International Nuclear Information System (INIS)

    Oliveira, Sergio R.; Mantuano, Natalia O.; Albrecht, Afonso S.

    2014-01-01

    Currently, the use of digital mammography in the early diagnosis of breast cancer is increasingly common due to the production of high definition image that allows to detect subtle changes in breast images profiles. However it is necessary to be an improvement of the technique used since some devices offer minimization parameters of entrance dose to the skin. Thus, this study seeks to examine how the qualification of technical professionals in radiology interferes with the use of the techniques applied in mammography. For this, survey was carried out in a hospital in the city of Rio de Janeiro, which evaluated the scans of 1190 patients undergoing routine mammography (It is considered routinely the 4 basic exhibitions: with 2 flow skull and 2 medium oblique side, excluding repeats and supplements) in 2013. The medical exposures analyzed obtained from a single full digital equipment, model Senographe DS were compared with three different procedures performed by professionals in mammography techniques. The images were classified according to exposure techniques available in the equipment: Standard (STD), contrast (CNT) and dose (dose), and to be selected as breast density of the patient. Comparing the variation of the radiographic technique in relation to the professional who made the exhibition, what is observed is that the professional B presented the best conduct in relation to radiological protection, because she considered breast density in the choice of technical equipment parameter. The professional A, which is newly formed, and C, which has more service time, almost did not perform variations in the pattern of exposure, even for different breast densities. Thus, we can conclude that there is a need to update the professionals so that the tools available of dose limitation and mamas variability to digital mammography are efficiently employed in the service routine and thus meet the requirements of current legislation

  10. Analysis Of The 2009 July Impact Debris In Jupiter'S Atmosphere

    Science.gov (United States)

    Sanchez-Lavega, Agustin; Hueso, R.; Legarreta, J.; Pérez-Hoyos, S.; García-Melendo, E.; Gómez, J. M.; Rojas, J. F.; Orton, G. S.; Wesley, A.; IOPW International Outer Planet Watch Team

    2009-09-01

    We report the analysis of images obtained by the contributors to the International Outer Planet Watch (IOPW) of the debris left in the atmosphere of Jupiter by the object that impacted the planet between 18 and 19 July 2009. The discovery images by Anthony Wesley in July 19.625 and the first two days of its tracking, shows a dark debris spot (continuum wavelength) located at planetocentric latitude -55.1 deg and 304.5 deg System III longitude. The imaging survey indicates that the spot was not present in July 18.375, so the impact occurred during a window between both dates. The main spot had a size of about 4,500 km and to its Northwest a thin debris halo of similar size was initially observed. Methane band images at a wavelength of 890 nm shows the spot to be bright indicating that the debris aerosols are highly placed in the atmosphere relative to surrounding clouds. At the central latitude of the impact, the Jovian flow has nearly zero speed but anticyclonic vorticity bounded by jets at -51.5 deg (directed westward with velocity -10 m/s) and at -57.5 deg (directed eastward with velocity 25 m/s). The morphology in the continuum and the spot brightness in the methane band strongly suggest that the feature was caused by a cometary or asteroidal impact, similar in behaviour to the SL9 impacts of 1994. This work has been funded by Spanish MEC AYA2006-07735 with FEDER support and Grupos Gobierno Vasco IT-464-07. RH acknowledges a "Ramón y Cajal” contract from MEC.

  11. Scientific Visualization for Atmospheric Data Analysis in Collaborative Virtual Environments

    Science.gov (United States)

    Engelke, Wito; Flatken, Markus; Garcia, Arturo S.; Bar, Christian; Gerndt, Andreas

    2016-04-01

    1 INTRODUCTION The three year European research project CROSS DRIVE (Collaborative Rover Operations and Planetary Science Analysis System based on Distributed Remote and Interactive Virtual Environments) started in January 2014. The research and development within this project is motivated by three use case studies: landing site characterization, atmospheric science and rover target selection [1]. Currently the implementation for the second use case is in its final phase [2]. Here, the requirements were generated based on the domain experts input and lead to development and integration of appropriate methods for visualization and analysis of atmospheric data. The methods range from volume rendering, interactive slicing, iso-surface techniques to interactive probing. All visualization methods are integrated in DLR's Terrain Rendering application. With this, the high resolution surface data visualization can be enriched with additional methods appropriate for atmospheric data sets. This results in an integrated virtual environment where the scientist has the possibility to interactively explore his data sets directly within the correct context. The data sets include volumetric data of the martian atmosphere, precomputed two dimensional maps and vertical profiles. In most cases the surface data as well as the atmospheric data has global coverage and is of time dependent nature. Furthermore, all interaction is synchronized between different connected application instances, allowing for collaborative sessions between distant experts. 2 VISUALIZATION TECHNIQUES Also the application is currently used for visualization of data sets related to Mars the techniques can be used for other data sets as well. Currently the prototype is capable of handling 2 and 2.5D surface data as well as 4D atmospheric data. Specifically, the surface data is presented using an LoD approach which is based on the HEALPix tessellation of a sphere [3, 4, 5] and can handle data sets in the order of

  12. Analysis of Δ14C variations in atmosphere

    International Nuclear Information System (INIS)

    Simon, J.; Sivo, A.; Richtarikova, M.; Holy, K.; Polaskova, A.; Bulko, M.; Hola, O.

    2005-01-01

    The Δ 14 C in the atmosphere have been measured and studied in two localities of Slovakia. The accomplished analysis proved the existence of the annual variations of the Δ 14 C with the attenuating amplitude and decreasing mean value. It seems to be logical and physically correct to describe the Δ 14 C time-dependence by the equation: y = Ae -at + Be -bt cos(ω 1 t + (φ)). The coefficients A, a, B, b, (φ) are listed in the table for both the localities. The observed variations of the Δ 14 C have a maximum in summer and minimum in winter .Probably it is caused by the higher requirement of the heat supply in winter season which is connected directly with the fossil CO 2 emissions and more intensive Suess effect. Summer maximum could be explained by the combination of the lower CO 2 emission rate and higher turbulent transport of the stratospheric 14 C to the troposphere. Using the Fourier harmonic analysis the amplitude spectra of the average annual variations were plotted. The obtained result shows that the variations have the high degree of symmetry. Furthermore, the obtained basic frequency ω 1 = 2π/12 [month -1 ] proves that the cyclic processes with the period of T = 12 [month] have a major influence on the 14 C amount in the troposphere. The presence of some higher-order harmonics is significant, but a physical interpretation has not yet been clear. In addition to the main frequency there are presented also 2ω 1 and 3ω 1 in Bratislava and 4ω 1 in Zlkovce data-set. The long-time average of the Δ 14 C in Zlkovce during years 1995-2004 is higher of about 6.6 o / oo than in Bratislava. It represents an unique evidence that the local CO 2 pollution affects the 14 C activity . The correlation on the level R 2 = 0,43 was found between Bratislava and Zlkovce atmospheric Δ 14 C data. (authors)

  13. Oxidation behavior of stainless steel 430 and 441 at 800 C in single (air/air) and dual atmosphere (air/hydrogen) exposures

    Energy Technology Data Exchange (ETDEWEB)

    Rufner, J.; Gannon, P.; White, P.; Deibert, M.; Teintze, S. [Chemical and Biological Engineering, Montana State University, 306 Cobleigh Hall, Bozeman, MT 59717-3920 (United States); Smith, R.; Chen, H. [Physics, Montana State University, 306 Cobleigh Hall, Bozeman, MT 59717-3920 (United States)

    2008-02-15

    Intermediate temperature ({proportional_to}800 {sup o}C) planar solid oxide fuel cells (SOFCs) allow the use of ferritic stainless steel (FSS) interconnects. SOFC FSS interconnects are used to stack individual cells into series, and are simultaneously exposed to air on the cathode side and fuel on the anode side, creating a 'dual atmosphere' exposure. The thermally grown oxide (TGO) layers on the air side of FSSs 430 and 441 were analyzed as a function of simulated dual atmosphere exposures (moist air/moist hydrogen) for up to 300 h. FSS 430 showed some changes in oxidation behavior, with a slight Fe concentration increase and localized Fe{sub 2}O{sub 3} nodule formation observed in the dual atmosphere TGO layer relative to its single atmosphere (air/air) counterpart. Significantly accelerated and anomalous oxidation was observed with FSS 441 subjected to dual atmosphere exposures compared with air/air exposures. The TGO layer formed on the 441 exposed to air/air was comprised of Mn-rich, Cr and Fe-containing isomorphic spinel surface crystallites, with a Cr{sub 2}O{sub 3} (eskolaite)-based bottom layer, having a total TGO layer thickness of <2{mu} m after 300 h. In contrast, the TGO layer formed on 441 during dual atmosphere exposure was much faster-growing (>6{mu} m in 20 h) and exhibited a continuous, porous Fe{sub 2}O{sub 3}-rich surface layer with a relatively thin (<2{mu} m) sublayer of similar composition to the TGO layer formed during the air/air exposure. Spontaneous TGO layer spallation was also observed for the air side of 441 exposed to dual atmosphere for >100h. The observed oxidation behavior and TGO layer evolution of 441 in both air/air and dual atmosphere are presented, with possible mechanisms and implications discussed. (author)

  14. Passive monitoring techniques for evaluating atmospheric ozone and nitrogen exposure and deposition to California ecosystems

    Science.gov (United States)

    Mark E. Fenn; Andrzej Bytnerowicz; Susan L. Schilling

    2018-01-01

    Measuring the exposure of ecosystems to ecologically relevant pollutants is needed for evaluating ecosystem effects and to identify regions and resources at risk. In California, ozone (O3) and nitrogen (N) pollutants are of greatest concern for ecological effects. "Passive" monitoring methods have been developed to obtain spatially...

  15. Analysis of the atmospheric upward radiation in low latitude area

    Science.gov (United States)

    Li, Haiying; Wu, Zhensen; Lin, Leke; Lu, Changsheng

    2016-10-01

    Remote sensing using THz wave has irreplaceable advantage comparing to the microwave and the infrared waves, and study on the THz remote sensing become more and more popular in recent years. The major applications of the remote sensing in THz wavelengths are the retrieval of the atmospheric parameters and the microphysical information of the ice cloud. The remote sensing of the atmosphere is based on the radiation of THz wave along the earth-space path of which the most significant part is the upward radiation of the atmosphere. The upward radiation of the atmosphere in sunny day in the low latitude area is computed and analyzed in this paper. The absorption of THz wave by the atmosphere is calculated using the formulations illustrated in the Recommendation ITU-R P.676 to save machine hour, the frequency range is then restricted below 1THz. The frequencies used for the retrieval of atmospheric parameters such as temperature and water content are usually a few hundred GHz, at the lower end of THz wavelengths, so this frequency range is sufficient. The radiation contribution of every atmospheric layer for typical frequencies such as absorption window frequencies and peak frequencies are analyzed. Results show that at frequencies which absorption is severe, information about lower atmosphere cannot reach the receiver onboard a satellite or other high platforms due to the strong absorption along the path.

  16. The exposure assessment of Rn-222 gas in the atmosphere(II)

    International Nuclear Information System (INIS)

    Ha, Chung Wo; Chang, Si Young; Seo, Kyung Won; Yoon, Yeo Chang; Kim, Jang Lyul; Yoon, Suk Chul; Chung, Rae Ik; Kim, Jong Soo; Park, Young Woong

    1991-01-01

    Dose assessment to inhalation exposure of indoor 222 Rn daughters in 12 residential areas in Korea has been performed by long term averaged radon concentrations measured with passive CR-39 radon cups. A simple mathematical lung dosimetry model based on the ICRP-30 was derived to estimate the indoor radon daughters exposure. The long term average indoor 222 Rn concentrations and corresponding equilibrium equivalent radon concentrations (EEC Rn ) in 12 areas showed a range of 33.82 ∼ 61.42 Bq.m -3 (median : 48.90 Bq.m -3 ) and of 13.53 ∼ 24.57 Bq.m -3 (median: 19.55 Bq.m -3 ), respectively. Reference dose conversion functions for evaluation of regional lung dose and effective dose equivalent for unit exposure to EEC Rn have been derived for an adult. The effective dose equivalent conversion factor was estimated to be 1.07 x 10 -5 mSv/Bq.h.m -3 and this conversion factor agreed well with that recommended by the ICRP and UNSCEAR report. The annual average dose equivalents(H) to Tracheo-Bronchial and Pulmonary region of the lung, and total lung from exposure to measured EEC Rn were estimated to be 17.52 mSv.y -l , 3.35 mSv.y -l and 20.90 mSv.y -1 , respectively, and the resulting effective dose equivalent(H E ) was estimated to be 1.25 mSv.y -l , which is almost 50% of the natural radiation exposure of 2.40 mSv.y -l reported by the UNSCEAR. (Author)

  17. Thermal Analysis of Solid Fuels in an Inert Atmosphere

    Science.gov (United States)

    Kijo-Kleczkowska, Agnieszka; Szumera, Magdalena; Środa, Katarzyna

    2017-12-01

    The paper takes the analysis of thermal studies of different types of fuels. It allowed diversification of fuels depending on their composition and origin. Consideration of coal, biomass and waste (coal mule, sewage sludge) as fuel is nowadays an important aspect of energy in our country. It should be emphasized that Poland power engineering is based up to 95% on coal - the primary fuel. Mining industry, forced to deliver power engineering more and better fuel, must however, use a deeper cleaning of coal. This results in a continuous increase waste in the form of mule flotation. The best method of disposing these mule is combustion and co-combustion with other fuels. On the other hand, commonly increasing awareness state of the environment and the need to reduce CO2 emissions energy industry have committed to implement alternative solutions in order to gain power, through, i.a.: development technologies use of biomass, which is one of the most promising renewable energy sources in Poland. The paper presents the results of research TG-DTA fuels made in an inert atmosphere.

  18. Atmospheric stability analysis and its relationship with the atmospheric pollution in Salamanca

    International Nuclear Information System (INIS)

    Fidalgo, M.R.; Garmendia, J.

    1989-01-01

    In this paper we have studied the relationship between the sulphur dioxide and suspended particulate matter concentrations and the atmospheric stability in Salamanca over 4 year (1978-1982). Of the various indices cited in the bibliography for estimating stratification stability, two were used. First, the Pasquill categories and later a method based on Montgomery's potential, which was the one that gave the best results. (Author)

  19. Vectorization of nuclear codes for atmospheric transport and exposure calculation of radioactive materials

    International Nuclear Information System (INIS)

    Asai, Kiyoshi; Shinozawa, Naohisa; Ishikawa, Hirohiko; Chino, Masamichi; Hayashi, Takashi

    1983-02-01

    Three computer codes MATHEW, ADPIC of LLNL and GAMPUL of JAERI for prediction of wind field, concentration and external exposure rate of airborne radioactive materials are vectorized and the results are presented. Using the continuous equation of incompressible flow as a constraint, the MATHEW calculates the three dimensional wind field by a variational method. Using the particle-in -cell method, the ADPIC calculates the advection and diffusion of radioactive materials in three dimensional wind field and terrain, and gives the concentration of the materials in each cell of the domain. The GAMPUL calculates the external exposure rate assuming Gaussian plume type distribution of concentration. The vectorized code MATHEW attained 7.8 times speedup by a vector processor FACOM230-75 APU. The ADPIC and GAMPUL are estimated to attain 1.5 and 4 times speedup respectively on CRAY-1 type vector processor. (author)

  20. Study of the Durability of Doped Lanthanum Manganite and Cobaltite Cathode Materials under ''Real World'' Air Exposure Atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Prabhakar [Univ. of Connecticut, Storrs, CT (United States); Mahapatra, Manoj [Univ. of Connecticut, Storrs, CT (United States); Ramprasad, Rampi [Univ. of Connecticut, Storrs, CT (United States); Minh, Nguyen [Univ. of California, San Diego, CA (United States); Misture, Scott [Alfred Univ., NY (United States)

    2014-11-30

    The overall objective of the program is to develop and validate mechanisms responsible for the overall structural and chemical degradation of lanthanum manganite as well as lanthanum ferrite cobaltite based cathode when exposed to “real world” air atmosphere exposure conditions during SOFC systems operation. Of particular interest are the evaluation and analysis of degradation phenomena related to and responsible for (a) products formation and interactions with air contaminants, (b) dopant segregation and oxide exolution at free surfaces, (c) cation interdiffusion and reaction products formation at the buried interfaces, (d) interface morphology changes, lattice transformation and the development of interfacial porosity and (e) micro-cracking and delamination from the stack repeat units. Reaction processes have been studied using electrochemical and high temperature materials compatibility tests followed by structural and chemical characterization. Degradation hypothesis has been proposed and validated through further experimentation and computational simulation.

  1. Performance Analysis of M-atmospheric FSO Links

    DEFF Research Database (Denmark)

    Lopez-Gonzalez, Francisco J.; Garrido-Balsellss, José María; Jurado-Navas, Antonio

    2016-01-01

    In this paper, a generalization of the Málaga atmospheric optical communications links treated as a finite number of Generalized-K distributed sub-channels is analyzed in terms of the average bit error rate and outage probability....

  2. Policemen exposure to atmospheric pollutants in Paris; Exposition des policiers aux polluants atmospheriques a Paris

    Energy Technology Data Exchange (ETDEWEB)

    Bugajny, Ch.; Coursimault, A.; Donati, J.; Vieillard, H. [Laboratoire Central de la Prefecture de Police de Paris, 75 (France); Ducos, P.; Gaudin, R. [Institut National de Recherche et de Securite, 54 - Vandoeuvre les Nancy (France)

    2000-07-01

    The objective of this study was to evaluate the effects of automotive pollution on police health in Paris, more particularly those that are working near streets and crossroads; police working indoors are included in measurements as a reference population. This work included individual exposure measurements to some urban pollution main indicators and biological determinations to estimate the impact of these pollutants on health. Biological measurements, including determinations of carboxyhemoglobin, lead in blood and trans, trans-muconic acid in urine were realised. Carbon monoxide and benzene individual exposure had been measured by the use of individual analysers and diffusive samplers respectively. Motorcycle policemen and policemen at crossroads are more exposed than reference population working indoor. CO mean exposure levels are 6, 8 mg/m{sup 3} for motorcycle policemen, 5, 4 mg/m{sup 3} for policemen at crossroads, compared to 3, 6 mg/m{sup 3} for policemen working indoors. Carboxyhemoglobin mean values before work are four to five times more important for smokers (4, 5 % HbCO) than no-smokers (1,0%HbCO). After work, these values are respectively 5,3 % and 1,1 %. Non-smokers agents don't reach the OMS value (2,5%HbCO), even after work. Smoking contributes to higher levels of CO in blood than car exhaust pollutants, even for high air pollutants concentrations. Lead blond levels, which average is 45{mu}g/l, are clearly smaller than the OMS value (200{mu}g/l). About non-smokers agents, benzene median exposures are 74 {mu}g/m{sup 3} for motorcycle policemen, 19 {mu}g/m{sup 3} for policemen at crossroads, compared to 8 {mu}g/m{sup 3} for sedentary agents. If motorcycle agents filled up the tank with gasoline, benzene median exposure level is 229 {mu}g/m{sup 3}. Differences between smokers and non-smokers benzene exposure are not significant. For non-smokers agents, median trans, trans muconic acid values after work are 0,06 mg/l for pollution exposed agents

  3. Regression analysis with categorized regression calibrated exposure: some interesting findings

    Directory of Open Access Journals (Sweden)

    Hjartåker Anette

    2006-07-01

    Full Text Available Abstract Background Regression calibration as a method for handling measurement error is becoming increasingly well-known and used in epidemiologic research. However, the standard version of the method is not appropriate for exposure analyzed on a categorical (e.g. quintile scale, an approach commonly used in epidemiologic studies. A tempting solution could then be to use the predicted continuous exposure obtained through the regression calibration method and treat it as an approximation to the true exposure, that is, include the categorized calibrated exposure in the main regression analysis. Methods We use semi-analytical calculations and simulations to evaluate the performance of the proposed approach compared to the naive approach of not correcting for measurement error, in situations where analyses are performed on quintile scale and when incorporating the original scale into the categorical variables, respectively. We also present analyses of real data, containing measures of folate intake and depression, from the Norwegian Women and Cancer study (NOWAC. Results In cases where extra information is available through replicated measurements and not validation data, regression calibration does not maintain important qualities of the true exposure distribution, thus estimates of variance and percentiles can be severely biased. We show that the outlined approach maintains much, in some cases all, of the misclassification found in the observed exposure. For that reason, regression analysis with the corrected variable included on a categorical scale is still biased. In some cases the corrected estimates are analytically equal to those obtained by the naive approach. Regression calibration is however vastly superior to the naive method when applying the medians of each category in the analysis. Conclusion Regression calibration in its most well-known form is not appropriate for measurement error correction when the exposure is analyzed on a

  4. Pollution level, inhalation exposure and lung cancer risk of ambient atmospheric polycyclic aromatic hydrocarbons (PAHs) in Taiyuan, China

    International Nuclear Information System (INIS)

    Xia Zhonghuan; Duan Xiaoli; Tao Shu; Qiu Weixun; Liu Di; Wang Yilong; Wei Siye; Wang Bin; Jiang Qiujing; Lu Bin; Song Yunxue; Hu Xinxin

    2013-01-01

    Passive air samplers were deployed to collect both gas and particulate phase polycyclic aromatic hydrocarbons in Taiyuan between 2009 and 2010. Annual average concentrations of BaP equivalent concentration (B[a]P eq ) in background, rural and urban areas were 2.90 ± 0.29, 23.2 ± 30.8 and 27.4 ± 28.1 ng/m 3 , respectively, with higher concentration in the winter than in other seasons. The median B[a]P eq concentrations of annual inhalation exposure were estimated to be in the range of 103–347 ng/d for all population groups in rural as well as in urban areas. The median values of incremental lifetime cancer risk (ILCR) induced by whole year inhalation exposure for all groups were basically larger than 10 −6 , with higher values in winter than in other seasons and in urban than in rural area. In the same season and area, the ILCR of adults was larger than other age groups and that of females was a little higher than males. - Highlights: ► The median values of ILCR were higher in winter than in other seasons. ► The median values of ILCR were higher in urban than in rural area. ► In the same season and area, the ILCR of adults was larger than other age groups. ► In the same season and area, the ILCR of females was a little higher than males. ► Exposure level and the cancer slope factor influenced the ILCR greatly. - The inhalation exposure and lung cancer risk of ambient atmospheric PAHs changed for different seasons, areas and population groups in Taiyuan, China.

  5. SUMS preliminary design and data analysis development. [shuttle upper atmosphere mass spectrometer experiment

    Science.gov (United States)

    Hinson, E. W.

    1981-01-01

    The preliminary analysis and data analysis system development for the shuttle upper atmosphere mass spectrometer (SUMS) experiment are discussed. The SUMS experiment is designed to provide free stream atmospheric density, pressure, temperature, and mean molecular weight for the high altitude, high Mach number region.

  6. Measurement of cardiopulmonary performance during acute exposure to a 2440-m equivalent atmosphere

    Science.gov (United States)

    Levitan, B. M.; Bungo, M. W.

    1982-01-01

    Each of 20 subjects (ranging in age from 18 to 38 years, 15 being male, five female) was given two Bruce Protocol symptom-limited maximum treadmill stress tests, breathing sea-level compressed air (20.9% O2) for one test and a 2440-m equivalent (15.5% O2) for the other. A significant difference was found to exist between measured VO2 max (p less than 0.0002) and exercise time (p less than 0.0004) for the two conditions. No significant differences were observed in heart rate or the recovery time to a respiratory quotient of less than 1. Hemoglobin saturation, as measured by an ear oximeter, averaged 95% for sea-level and 91% for the 2440-m equivalent gases. These results support a 2440-m equivalent contingency atmosphere in the Space Shuttle prior to donning a low-pressure suit for the purpose reducing nitrogen washout times.

  7. [Assessment of a risk from exposure to atmosphere bus industrial emissions].

    Science.gov (United States)

    Stepkin, Iu I; Kuzmichev, M K

    2009-01-01

    The carcinogenic and noncarcinogenic risks to health were estimated in accordance with the requirements stated in the guide P 2.1.10.1920-04 "Guidelines for assessing the health risk in the population exposed to the chemicals polluting the environment" (approved by G. G. Onishchenko, state sanitary inspector on March 5, 2004) and comprised four successive steps: 1) identification of a hazard; 2) estimation of a dose-response relationship; 3) evaluation of exposure of the population to chemical substances; 4) characterization of a risk, by calculating the individual carcinogenic risk, hazard coefficients and indices characterizing the noncarcinogenic risk. The performed assessment of the health risk to the population living in the area exposed to the ambient air pollutant emissions by the AOA "Shinnyi Kompleks Amtel-Chenozymye" (Amtel-Chernozem Tyre Complex) allowed determination of priority pollutants, by taking into account their effect on human health. The individual carcinogenic risk to health has been found to be higher than the acceptable (safe) level (10-4) was due to the probable exposure to a 2-heptane fraction (nefras ChS 94/99) and hexavalent chromium. The highest non-carcinogenic risk to human was also due to the heptane fraction (nefras ChS 94/99) (hazard coefficient > 1).

  8. Accelerated atmospheric corrosion testing using a cyclic wet/dry exposure test

    International Nuclear Information System (INIS)

    Lyon, S.B.; Thompson, G.E.; Johnson, J.E.; Wood, G.C.

    1989-01-01

    Aluminum corrosion is important in overhead electrical conductors constructed from aluminum wire centrally reinforced by galvanized steel strands. Inspection of conductor after long service has implicated rubber bushing material, on the outside, and the galvanized strands, on the inside, as providing potential galvanic sites for the initiation of rapid aluminum corrosion. Therefore, the galvanic corrosion of aluminum in contact with graphite-loaded neoprene rubber, hot-dip galvanized steel and steel was assessed in a cyclic wet/dry exposure test using mixed-salts spray solutions containing appropriate ratios of sulfate and chloride ion. Aluminum was found to corrode at between 3 to 6 times its uncoupled rate when associated with the rubber material. While the eta-phase, relatively pure Zn, galvanized layer remained intact, galvanic corrosion of aluminum was slow. However, on exposure of the zeta-phase, Zn/Fe intermetallic layer, aluminum corroded about 35 times faster than expected in a solution with a high level of Cl - ion. The importance of these data to conductor lifetime is discussed

  9. Noble gases in Mars atmosphere: new precise analysis with Paloma

    Science.gov (United States)

    Sarda, Ph.; Paloma Team

    2003-04-01

    The Viking mission embarked a mass spectrometer designed by Alfred O. Nier that yielded the first determination of the elemental and isotopic composition of noble gases in Mars atmosphere. For example, the 40Ar/36Ar ratio in martian air is roughly 10 fold that in terrestrial air. This extraordinary accomplishment, however, has furnished only partial results with large analytical uncertainties. For example, we do not know the isotopic composition of helium, and only very poorly that of Ne, Kr and Xe. In planetary science, it is fundamental to have a good knowledge of the atmosphere because this serves as a reference for all further studies of volatiles. In addition, part of our present knowledge of Mars atmosphere is based on the SNC meteorites, and again points to important differences between the atmospheres of Earth and Mars. For example the 129Xe/132Xe ratio of martian atmosphere would be twice that of terrestrial air and the 36Ar/38Ar ratio strongly different from the terrestrial or solar value. There is a need for confirming that the atmospheric components found in SNC meteorites actually represents the atmosphere of Mars, or to determine how different they are. Paloma is an instrument designed to generate elemental and isotopic data for He, Ne, Ar, Kr and Xe (and other gases) using a mass spectrometer with a purification and separation line. Gas purification and separation did not exist on the Vicking instrument. Because Paloma includes purification and separation, we expect strong improvement in precision. Ne, Ar and Xe isotope ratios should be obtained with an accuracy of better than 1%. Determination of the presently unknown ^3He/^4He ratio is also awaited from this experiment. Knowledge of noble gas isotopes in Mars atmosphere will allow some insight into major planetary processes such as degassing (^3He/^4He, 40Ar/36Ar, 129Xe/130Xe, 136Xe/130Xe), gravitational escape to space (^3He/^4He, 20Ne/22Ne), hydrodynamic escape and/or impact erosion of the

  10. In vitro exposure of Acer negundo pollen to atmospheric levels of SO₂ and NO₂: effects on allergenicity and germination.

    Science.gov (United States)

    Sousa, Raquel; Duque, Laura; Duarte, Abel J; Gomes, Carlos R; Ribeiro, Helena; Cruz, Ana; Esteves da Silva, Joaquim C G; Abreu, Ilda

    2012-02-21

    In the last years, a rising trend of pollen allergies in urban areas has been attributed to atmospheric pollution. In this work, we investigated the effects of SO(2) and NO(2) on the protein content, allergenicity, and germination rate of Acer negundo pollen. A novel environmental chamber was assembled to exposure pollen samples with SO(2) or NO(2) at two different levels: just below and two times the atmospheric hour-limit value acceptable for human health protection in Europe. Results showed that protein content was lower in SO(2)-exposed pollen samples and slightly higher in NO(2)-exposed pollen compared to the control sample. No different polypeptide profiles were revealed by SDS-PAGE between exposed and nonexposed pollen, but the immunodetection assays indicated higher IgE recognition by all sera of sensitized patients to Acer negundo pollen extracts in all exposed samples in comparison to the nonexposed samples. A decrease in the germination rate of exposed in contrast to nonexposed pollen was verified, which was more pronounced for NO(2)-exposed samples. Our results indicated that in urban areas, concentrations of SO(2) and NO(2) below the limits established for human protection can indirectly aggravate pollen allergy on predisposed individuals and affect plant reproduction.

  11. Atmospheric heavy metal deposition in Europe estimated by moss analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ruehling, Aa. [Swedish Environmental Research Inst., Lund (Sweden). Dept. of Ecology

    1995-12-31

    Atmospheric heavy metal deposition in Europe including 21 countries was monitored in 1990-1992 by the moss technique. This technique is based on the fact that the concentrations of heavy metals in moss are closely correlated to atmospheric deposition. This was the first attempt to map heavy metal deposition in this large area. The objectives of the project were to characterise qualitatively and quantitatively the regional atmospheric deposition pattern of heavy metals in background areas in Europe, to indicate the location of important heavy metal pollution sources and to allow retrospective comparisons with similar studies. The present survey is a follow-up of a joint Danish and Swedish project in 1980 and an extended survey in 1985 within the framework of the Nordic Council of Ministers. In Sweden, heavy-metal deposition was first mapped on a nation-wide scale in 1968-1971 and 1975. (author)

  12. Atmospheric heavy metal deposition in Europe estimated by moss analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ruehling, Aa [Swedish Environmental Research Inst., Lund (Sweden). Dept. of Ecology

    1996-12-31

    Atmospheric heavy metal deposition in Europe including 21 countries was monitored in 1990-1992 by the moss technique. This technique is based on the fact that the concentrations of heavy metals in moss are closely correlated to atmospheric deposition. This was the first attempt to map heavy metal deposition in this large area. The objectives of the project were to characterise qualitatively and quantitatively the regional atmospheric deposition pattern of heavy metals in background areas in Europe, to indicate the location of important heavy metal pollution sources and to allow retrospective comparisons with similar studies. The present survey is a follow-up of a joint Danish and Swedish project in 1980 and an extended survey in 1985 within the framework of the Nordic Council of Ministers. In Sweden, heavy-metal deposition was first mapped on a nation-wide scale in 1968-1971 and 1975. (author)

  13. Atmospheric corrosion performance of different steels in early exposure in the coastal area region West Java, Indonesia

    Science.gov (United States)

    Nuraini, Lutviasari; Prifiharni, Siska; Priyotomo, Gadang; Sundjono, Gunawan, Hadi; Purawiardi, Ibrahim

    2018-05-01

    The performance of carbon steel, galvanized steel and aluminium after one month exposed in the atmospheric coastal area, which is in Limbangan and Karangsong Beach, West Java, Indonesia was evaluated. The corrosion rate was determined by weight loss method and the morphology of the steel after exposed was observed by Scanning Electron Microscopy(SEM)/Energy Dispersive X-Ray Analysis(EDX). The site was monitored to determine the chloride content in the marine atmosphere. Then, the corrosion products formed at carbon steel were characterized by X-Ray diffraction (XRD). The result showed the aggressively corrosion in Karangsong beach, indicated from the corrosion rate of carbon steel, galvanized steel and aluminium were 38.514 mpy; 4.7860 mpy and 0.5181 mpy, respectively. While in Limbangan Beach the corrosion rate of specimen carbon steel, galvanized steel and aluminium were 3.339; 0.219 and 0.166 mpy, respectively. The chloride content was found to be the main factor that influences in the atmospheric corrosion process in this area. Chloride content accumulated in Karangsong and Limbangan was 497 mg/m2.day and 117 mg/m2.day, respectively. The XRD Analysis on each carbon steel led to the characterization of a complex mixture of iron oxides phases.

  14. Oxidative modification and electrochemical inactivation of Escherichia coli upon cold atmospheric pressure plasma exposure.

    Directory of Open Access Journals (Sweden)

    Marlène Dezest

    Full Text Available Cold atmospheric pressure plasmas (CAPPs are known to have bactericidal effects but the mechanism of their interaction with microorganisms remains poorly understood. In this study the bacteria Escherichia coli were used as a model and were exposed to CAPPs. Different gas compositions, helium with or without adjunctions of nitrogen or oxygen, were used. Our results indicated that CAPP induced bacterial death at decontamination levels depend on the duration, post-treatment storage and the gas mixture composition used for the treatment. The plasma containing O2 in the feeding gas was the most aggressive and showed faster bactericidal effects. Structural modifications of treated bacteria were observed, especially significant was membrane leakage and morphological changes. Oxidative stress caused by plasma treatment led to significant damage of E. coli. Biochemical analyses of bacterial macromolecules indicated massive intracellular protein oxidation. However, reactive oxygen and nitrogen species (RONS are not the only actors involved in E. coli's death, electrical field and charged particles could play a significant role especially for He-O2 CAPP.

  15. Analysis of smoke trailers at individual classes of atmosphere stability

    International Nuclear Information System (INIS)

    Carach, V.; Macala, J.

    2007-01-01

    At the present most endangered element of the environment is currently atmosphere and its pollution that rapidly accrue. Pollutants are emitted from air pollution sources. The output of pollutant from air pollution source is creating so-called smoke screen. Smoke screens can be observed from point sources of air pollution - smokestacks, up-cast. The purpose of this article was to build theoretical models of smoke screens rise from point source at different meteorological conditions characterized with fifth classes of atmosphere stability. (authors)

  16. Non-destructive neutron activation analysis of atmospheric pollutants

    International Nuclear Information System (INIS)

    Owlya, A.; Kasrai, M.; Massoumi, R.

    1976-01-01

    The concentration of elements in atmospheric particulate in an urban area were determined by means of a Ge(Li) detector. Samples were collected on a Millipore filter at a single location during three seasons of the year and the results compared. These results are compared with results for the same elements in other cities. It was concluded that in a dry climate, at least two parameters are related to seasonal changes in trace element concentration in the atmosphere-rain and snowfall, and the reducation of vertical diffusion of airborne particulates (author)

  17. Measurements and simulations of the radiation exposure to aircraft crew workplaces due to cosmic radiation in the atmosphere

    International Nuclear Information System (INIS)

    Beck, P.; Latocha, M.; Dorman, L.; Pelliccioni, M.; Rollet, S.

    2007-01-01

    As required by the European Directive 96/29/Euratom, radiation exposure due to natural ionizing radiation has to be taken into account at workplaces if the effective dose could become more than 1 mSv per year. An example of workers concerned by this directive is aircraft crew due to cosmic radiation exposure in the atmosphere. Extensive measurement campaigns on board aircraft have been carried out to assess ambient dose equivalent. A consortium of European dosimetry institutes within EURADOS WG5 summarized experimental data and results of calculations, together with detailed descriptions of the methods for measurements and calculations. The radiation protection quantity of interest is the effective dose, E (ISO). The comparison of results by measurements and calculations is done in terms of the operational quantity ambient dose equivalent, H*(10). This paper gives an overview of the EURADOS Aircraft Crew In-Flight Database and it presents a new empirical model describing fitting functions for this data. Furthermore, it describes numerical simulations performed with the Monte Carlo code FLUKA-2005 using an updated version of the cosmic radiation primary spectra. The ratio between ambient dose equivalent and effective dose at commercial flight altitudes, calculated with FLUKA-2005, is discussed. Finally, it presents the aviation dosimetry model AVIDOS based on FLUKA-2005 simulations for routine dose assessment. The code has been developed by Austrian Research Centers (ARC) for the public usage (http://avidos.healthphysics.at. (authors)

  18. Analysis of intervention strategies for inhalation exposure to polycyclic aromatic hydrocarbons and associated lung cancer risk based on a Monte Carlo population exposure assessment model.

    Science.gov (United States)

    Zhou, Bin; Zhao, Bin

    2014-01-01

    It is difficult to evaluate and compare interventions for reducing exposure to air pollutants, including polycyclic aromatic hydrocarbons (PAHs), a widely found air pollutant in both indoor and outdoor air. This study presents the first application of the Monte Carlo population exposure assessment model to quantify the effects of different intervention strategies on inhalation exposure to PAHs and the associated lung cancer risk. The method was applied to the population in Beijing, China, in the year 2006. Several intervention strategies were designed and studied, including atmospheric cleaning, smoking prohibition indoors, use of clean fuel for cooking, enhancing ventilation while cooking and use of indoor cleaners. Their performances were quantified by population attributable fraction (PAF) and potential impact fraction (PIF) of lung cancer risk, and the changes in indoor PAH concentrations and annual inhalation doses were also calculated and compared. The results showed that atmospheric cleaning and use of indoor cleaners were the two most effective interventions. The sensitivity analysis showed that several input parameters had major influence on the modeled PAH inhalation exposure and the rankings of different interventions. The ranking was reasonably robust for the remaining majority of parameters. The method itself can be extended to other pollutants and in different places. It enables the quantitative comparison of different intervention strategies and would benefit intervention design and relevant policy making.

  19. Analysis of intervention strategies for inhalation exposure to polycyclic aromatic hydrocarbons and associated lung cancer risk based on a Monte Carlo population exposure assessment model.

    Directory of Open Access Journals (Sweden)

    Bin Zhou

    Full Text Available It is difficult to evaluate and compare interventions for reducing exposure to air pollutants, including polycyclic aromatic hydrocarbons (PAHs, a widely found air pollutant in both indoor and outdoor air. This study presents the first application of the Monte Carlo population exposure assessment model to quantify the effects of different intervention strategies on inhalation exposure to PAHs and the associated lung cancer risk. The method was applied to the population in Beijing, China, in the year 2006. Several intervention strategies were designed and studied, including atmospheric cleaning, smoking prohibition indoors, use of clean fuel for cooking, enhancing ventilation while cooking and use of indoor cleaners. Their performances were quantified by population attributable fraction (PAF and potential impact fraction (PIF of lung cancer risk, and the changes in indoor PAH concentrations and annual inhalation doses were also calculated and compared. The results showed that atmospheric cleaning and use of indoor cleaners were the two most effective interventions. The sensitivity analysis showed that several input parameters had major influence on the modeled PAH inhalation exposure and the rankings of different interventions. The ranking was reasonably robust for the remaining majority of parameters. The method itself can be extended to other pollutants and in different places. It enables the quantitative comparison of different intervention strategies and would benefit intervention design and relevant policy making.

  20. Impacts of Mercury Pollution Controls on Atmospheric Mercury Concentration and Occupational Mercury Exposure in a Hospital.

    Science.gov (United States)

    Li, Ping; Yang, Yan; Xiong, Wuyan

    2015-12-01

    Mercury (Hg) and Hg-containing products are used in a wide range of settings in hospitals. Hg pollution control measures were carried out in the pediatric ward of a hospital to decrease the possibility of Hg pollution occurring and to decrease occupational Hg exposure. Total gaseous Hg (TGM) concentrations in the pediatric ward and hair and urine Hg concentrations for the pediatric staff were determined before and after the Hg pollution control measures had been implemented. A questionnaire survey performed indicated that the pediatric staff had little understanding of Hg pollution and that appropriate disposal techniques were not always used after Hg leakage. TGM concentrations in the pediatric ward and urine Hg (UHg) concentrations for the pediatric staff were 25.7 and 22.2% lower, respectively, after the Hg pollution control measures had been implemented than before, which indicated that the control measures were effective. However, TGM concentrations in the pediatric ward remained significantly higher than background concentrations and UHg concentrations for the pediatric staff were remained significantly higher than the concentrations in control group, indicating continued existence of certain Hg pollution.

  1. Nonlinear phased analysis of reinforced concrete tunnels under fire exposure

    NARCIS (Netherlands)

    Lilliu, G.; Meda, A.

    2013-01-01

    Fire analysis of precast segmental tunnels involves several problems, mainly related to the soil-structure interaction during fire exposure, coupled with material degradation. Temperature increase in the tunnel is the cause of thermal expansion of the lining, which is resisted by the soil pressure.

  2. Spatial Analysis of Human Exposure and Vulnerability to Coastal ...

    African Journals Online (AJOL)

    Disasters in coastal cities have shown an ever-increasing frequency of occurrence. Population growth and urbanisation have increased the vulnerability of properties and societies in coastal flood-prone areas. Analysis of human exposure and vulnerability is one of the main strategies used to determine the necessary ...

  3. Validation Study for an Atmospheric Dispersion Model, Using Effective Source Heights Determined from Wind Tunnel Experiments in Nuclear Safety Analysis

    Directory of Open Access Journals (Sweden)

    Masamichi Oura

    2018-03-01

    Full Text Available For more than fifty years, atmospheric dispersion predictions based on the joint use of a Gaussian plume model and wind tunnel experiments have been applied in both Japan and the U.K. for the evaluation of public radiation exposure in nuclear safety analysis. The effective source height used in the Gaussian model is determined from ground-level concentration data obtained by a wind tunnel experiment using a scaled terrain and site model. In the present paper, the concentrations calculated by this method are compared with data observed over complex terrain in the field, under a number of meteorological conditions. Good agreement was confirmed in near-neutral and unstable stabilities. However, it was found to be necessary to reduce the effective source height by 50% in order to achieve a conservative estimation of the field observations in a stable atmosphere.

  4. Dynamical Analysis of the Lorenz-84 Atmospheric Circulation Model

    Directory of Open Access Journals (Sweden)

    Hu Wang

    2014-01-01

    Full Text Available The dynamical behaviors of the Lorenz-84 atmospheric circulation model are investigated based on qualitative theory and numerical simulations. The stability and local bifurcation conditions of the Lorenz-84 atmospheric circulation model are obtained. It is also shown that when the bifurcation parameter exceeds a critical value, the Hopf bifurcation occurs in this model. Then, the conditions of the supercritical and subcritical bifurcation are derived through the normal form theory. Finally, the chaotic behavior of the model is also discussed, the bifurcation diagrams and Lyapunov exponents spectrum for the corresponding parameter are obtained, and the parameter interval ranges of limit cycle and chaotic attractor are calculated in further. Especially, a computer-assisted proof of the chaoticity of the model is presented by a topological horseshoe theory.

  5. Sensitivity Analysis for Atmospheric Infrared Sounder (AIRS) CO2 Retrieval

    Science.gov (United States)

    Gat, Ilana

    2012-01-01

    The Atmospheric Infrared Sounder (AIRS) is a thermal infrared sensor able to retrieve the daily atmospheric state globally for clear as well as partially cloudy field-of-views. The AIRS spectrometer has 2378 channels sensing from 15.4 micrometers to 3.7 micrometers, of which a small subset in the 15 micrometers region has been selected, to date, for CO2 retrieval. To improve upon the current retrieval method, we extended the retrieval calculations to include a prior estimate component and developed a channel ranking system to optimize the channels and number of channels used. The channel ranking system uses a mathematical formalism to rapidly process and assess the retrieval potential of large numbers of channels. Implementing this system, we identifed a larger optimized subset of AIRS channels that can decrease retrieval errors and minimize the overall sensitivity to other iridescent contributors, such as water vapor, ozone, and atmospheric temperature. This methodology selects channels globally by accounting for the latitudinal, longitudinal, and seasonal dependencies of the subset. The new methodology increases accuracy in AIRS CO2 as well as other retrievals and enables the extension of retrieved CO2 vertical profiles to altitudes ranging from the lower troposphere to upper stratosphere. The extended retrieval method for CO2 vertical profile estimation using a maximum-likelihood estimation method. We use model data to demonstrate the beneficial impact of the extended retrieval method using the new channel ranking system on CO2 retrieval.

  6. Space Shuttle and Space Station Radio Frequency (RF) Exposure Analysis

    Science.gov (United States)

    Hwu, Shian U.; Loh, Yin-Chung; Sham, Catherine C.; Kroll, Quin D.

    2005-01-01

    This paper outlines the modeling techniques and important parameters to define a rigorous but practical procedure that can verify the compliance of RF exposure to the NASA standards for astronauts and electronic equipment. The electromagnetic modeling techniques are applied to analyze RF exposure in Space Shuttle and Space Station environments with reasonable computing time and resources. The modeling techniques are capable of taking into account the field interactions with Space Shuttle and Space Station structures. The obtained results illustrate the multipath effects due to the presence of the space vehicle structures. It's necessary to include the field interactions with the space vehicle in the analysis for an accurate assessment of the RF exposure. Based on the obtained results, the RF keep out zones are identified for appropriate operational scenarios, flight rules and necessary RF transmitter constraints to ensure a safe operating environment and mission success.

  7. PREFACE: SPECIAL SECTION OF THE JOURNAL OF AIR & WASTE MANAGEMENT ASSOCIATION FOR PARTICULATE MATTER: ATMOSPHERIC SCIENCES, EXPOSURE AND THE FOURTH COLLOQUIUM ON PM AND HUMAN HEALTH

    Science.gov (United States)

    This dedicated issue of the Journal of the Air & Waste Management Association contains 17 peer-reviewed scientific papers that were presented at the specialty conference, “Particulate Matter: Atmospheric Sciences, Exposure and the Fourth Colloquium on PM and Human Health,” that w...

  8. Fungal community composition and function after long-term exposure of northern forests to elevated atmospheric CO2 and tropospheric O3

    Science.gov (United States)

    Ivan P. Edwards; Donald R. Zak

    2011-01-01

    The long-term effects of rising atmospheric carbon dioxide (CO2) and tropospheric O3 concentrations on fungal communities in soil are not well understood. Here, we examine fungal community composition and the activities of cellobiohydrolase and N-acetylglucosaminidase (NAG) after 10 years of exposure to 1...

  9. Assessment of people exposure to contamination with radioactive substances removed to the atmosphere from nuclear objects of Swierk Centre, Poland, in the period of 1987-1992

    International Nuclear Information System (INIS)

    Filipiak, B.; Nowicki, K.

    1995-01-01

    The exposure of particular persons, living in the near surroundings of Nuclear Centre - Swierk near Warsaw, Poland, to radioactive substances removed to the atmosphere during the period 1987-1992 has been assessed. The effective dose equivalent for statistically critical groups of persons has been estimated. The results have been compared with maximum permitted dose limits. 17 refs, 12 tabs

  10. Mediation analysis with time varying exposures and mediators.

    Science.gov (United States)

    VanderWeele, Tyler J; Tchetgen Tchetgen, Eric J

    2017-06-01

    In this paper we consider causal mediation analysis when exposures and mediators vary over time. We give non-parametric identification results, discuss parametric implementation, and also provide a weighting approach to direct and indirect effects based on combining the results of two marginal structural models. We also discuss how our results give rise to a causal interpretation of the effect estimates produced from longitudinal structural equation models. When there are time-varying confounders affected by prior exposure and mediator, natural direct and indirect effects are not identified. However, we define a randomized interventional analogue of natural direct and indirect effects that are identified in this setting. The formula that identifies these effects we refer to as the "mediational g-formula." When there is no mediation, the mediational g-formula reduces to Robins' regular g-formula for longitudinal data. When there are no time-varying confounders affected by prior exposure and mediator values, then the mediational g-formula reduces to a longitudinal version of Pearl's mediation formula. However, the mediational g-formula itself can accommodate both mediation and time-varying confounders and constitutes a general approach to mediation analysis with time-varying exposures and mediators.

  11. Exposure to atmospheric pms, pahs, pcdd/fs and metals near an open air waste burning site in Beirut

    Directory of Open Access Journals (Sweden)

    Rima Baalbaki

    2016-12-01

    Full Text Available Baalbaki, R., El Hage, R., Nassar, J., Gerard, J., Saliba, N.B., Zaarour, R., Abboud, M., Wehbeh, F., Khalaf, L.K., Shihadeh, A.L., Saliba, N.A. 2016. Exposure to atmospheric PMS, PAHS, PCDD/FS and metals near an open air waste burning site in Beirut. Lebanese Science Journal, 17(2: 91-103. Since July 2015, Lebanon has experienced the worst solid waste management crisis in its history. Consequently, open-air waste burning in the vicinity of highly populated areas in Beirut has become a common practice. This study evaluates the effects of open-air dumping and burning on local air quality and public health. The levels of particulate matter (PM10, PM2.5, gaseous and particle-bound polycyclic aromatic hydrocarbons (PAHs, polychlorinated dibenzo-dioxins and furans (PCDD/Fs, and particle-bound metals at a residence close to waste burning are reported. Concentrations, determined between October 2 and December 2, 2015, were compared either to previous measurements or to measurements taken away from a nearby burning incident, and after it had rained. Subsequently, the cancer risk due to exposure to these chemicals was assessed. Results showed alarming increases in pollutant concentrations which was translated into an increase in short-term cancer risk from about 1 to 20 people per million on the days when waste was being burned. Findings were shared with the public to warn the community against the dangers of waste mismanagement, and underline the obvious need for solid waste management at the governmental and municipal levels.

  12. Evaluation of atmospheric dispersion/consequence models supporting safety analysis

    International Nuclear Information System (INIS)

    O'Kula, K.R.; Lazaro, M.A.; Woodard, K.

    1996-01-01

    Two DOE Working Groups have completed evaluation of accident phenomenology and consequence methodologies used to support DOE facility safety documentation. The independent evaluations each concluded that no one computer model adequately addresses all accident and atmospheric release conditions. MACCS2, MATHEW/ADPIC, TRAC RA/HA, and COSYMA are adequate for most radiological dispersion and consequence needs. ALOHA, DEGADIS, HGSYSTEM, TSCREEN, and SLAB are recommended for chemical dispersion and consequence applications. Additional work is suggested, principally in evaluation of new models, targeting certain models for continued development, training, and establishing a Web page for guidance to safety analysts

  13. Atmospheric stability analysis over statically and dynamically rough surfaces

    Science.gov (United States)

    Maric, Emina; Metzger, Meredith; Singha, Arindam; Sadr, Reza

    2011-11-01

    The ratio of buoyancy flux to turbulent kinetic energy production in the atmospheric surface layer is investigated experimentally for air flow over two types of surfaces characterized by static and dynamic roughness. In this study, ``static'' refers to the time-invariant nature of naturally-occurring roughness over a mud/salt playa; while, ``dynamic'' refers to the behavior of water waves along an air-water interface. In both cases, time-resolved measurements of the momentum and heat fluxes were acquired from synchronized 3D sonic anemometers mounted on a vertical tower. Field campaigns were conducted at two sites, representing the ``statically'' and ``dynamically'' rough surfaces, respectively: (1) the SLTEST facility in Utah's western desert, and (2) the new Doha airport in Qatar under construction along the coast of the Persian Gulf. Note, at site 2, anemometers were located directly above the water by extension from a tower secured to the end of a 1 km-long pier. Comparisons of the Monin-Obukhov length, flux Richardson number, and gradient Richardson number are presented, and discussed in the context of the observed evolution of the turbulent spectra in response to diurnal variations of atmospheric stability. Supported by the Qatar National Research Fund.

  14. Causal mediation analysis for longitudinal data with exogenous exposure.

    Science.gov (United States)

    Bind, M-A C; Vanderweele, T J; Coull, B A; Schwartz, J D

    2016-01-01

    Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different types of longitudinal measures of the mediator and outcome, we assume two generalized mixed-effects models for both the mediator and the outcome. The model for the mediator has subject-specific random intercepts and random exposure slopes for each cluster, and the outcome model has random intercepts and random slopes for the exposure, the mediator, and their interaction. We also expand our approach to settings with multiple mediators and derive the mediated effects, jointly through all mediators. Our method requires the absence of time-varying confounding with respect to the exposure and the mediator. This assumption is achieved in settings with exogenous exposure and mediator, especially when exposure and mediator are not affected by variables measured at earlier time points. We apply the methodology to data from the Normative Aging Study and estimate the direct and indirect effects, via DNA methylation, of air pollution, and temperature on intercellular adhesion molecule 1 (ICAM-1) protein levels. Our results suggest that air pollution and temperature have a direct effect on ICAM-1 protein levels (i.e. not through a change in ICAM-1 DNA methylation) and that temperature has an indirect effect via a change in ICAM-1 DNA methylation. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Investigation of the various factors affecting the response of passive configuration track etch dosimeters to working level hour exposure in radon and radon daughter atmospheres. Final report

    International Nuclear Information System (INIS)

    Lovett, D.B.

    1976-01-01

    The work described in this report was directed toward identifying and devising methods to minimize the previously observed variability between working level hour exposures and the alpha particle track densities resulting on Track Etch films exposed to mine atmospheres containing radon and radon daughters. The disequilibrium between radon and its daughters was shown to directly affect the Track Etch film calibration factor. The wide range of disequilibrium states possible in mine situations amply explains the variability in the previous tests. A file of published mine atmosphere composition data was compiled and was used, along with atmospheric compositions derived from several theoretical models of the atmospheric behavior, to evaluate the variability of several dosimeter configurations and concepts

  16. Causal mediation analysis for longitudinal data with exogenous exposure

    OpenAIRE

    Bind, M.-A. C.; Vanderweele, T. J.; Coull, B. A.; Schwartz, J. D.

    2015-01-01

    Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different type...

  17. Uncertainty analysis of atmospheric deposition simulation of radiocesium and radioiodine from Fukushima Daiichi Nuclear Power Plant

    Science.gov (United States)

    Morino, Yu; Ohara, Toshimasa; Yumimoto, Keiya

    2014-05-01

    than particles. Analysis of 131I deposition gives us better constraint for the atmospheric simulation of 131I, which is important in assessing public radiation exposure.

  18. Study of spatiotemporal variation of atmospheric mercury and its human exposure around an integrated steel plant, India

    Science.gov (United States)

    Pervez, S.; Koshle, A.; Pervez, Y.

    2010-06-01

    Mercury release by coal combustion has been significantly increased in India. Mercury content in coal has been analyzed to 0.272 ppm by Central Pollution Control Board. Toxicological effects of elemental Hg (Hg0) exposure include respiratory and renal failures, cardiac arrest, and cerebral oedema, while subclinical exposure may induce kidney, behavioral, and cognitive dysfunctions. The present work is focused on dispersion pattern and inter-phase exchange phenomena of ambient mercury between air-particulate matter evaluations of alongwith dominance of various major routes of human exposure-dose response using regression analysis around an integrated steel plant in central India. Source-downwind type stratified random sampling plan using longitudinal study design has been adopted for ambient monitoring of total mercury, while representative sampling plant has been adopted for persona exposure-dose response study In space-time framework. Control sites and subjects have been chosen from uncontaminated area (100 km away from any industrial activities). 06 ambient air monitoring stations and 17 subjects from workers, non-workers but local residents' categories and from controlled sites have been chosen for the study. Samples of mercury biomarkers (blood, breast milk and urine) have also been collected from same subjects in each month during sampling period. The sampling period was March 2005 to February 2006 . Samples of 30% acidified KMnO4 for air-Hg absorption, PM10, RPM and biological samples were analyzed for total mercury by ICP-AES using standard methods. Local soils and ground water were also monitored for total mercury content during the sampling period. Results have shown that mercury concentration is very high compared to prescribed limits in all receptors. Results of exchange phenomenon have shown the higher transfer of mercury from air to particulate during combustion in steel plant environment due to presence of huge amount of iron particles, in contrast to

  19. Uncertainty analysis of atmospheric friction torque on the solid Earth

    Directory of Open Access Journals (Sweden)

    Haoming Yan

    2016-05-01

    Full Text Available The wind stress acquired from European Centre for Medium-Range Weather Forecasts (ECMWF, National Centers for Environmental Prediction (NCEP climate models and QSCAT satellite observations are analyzed by using frequency-wavenumber spectrum method. The spectrum of two climate models, i.e., ECMWF and NCEP, is similar for both 10 m wind data and model output wind stress data, which indicates that both the climate models capture the key feature of wind stress. While the QSCAT wind stress data shows the similar characteristics with the two climate models in both spectrum domain and the spatial distribution, but with a factor of approximately 1.25 times larger than that of climate models in energy. These differences show the uncertainty in the different wind stress products, which inevitably cause the atmospheric friction torque uncertainties on solid Earth with a 60% departure in annual amplitude, and furtherly affect the precise estimation of the Earth's rotation.

  20. Atmospheric Ionizing Radiation (AIR) ER-2 Preflight Analysis

    Science.gov (United States)

    Tai, Hsiang; Wilson, John W.; Maiden, D. L.

    1998-01-01

    Atmospheric ionizing radiation (AIR) produces chemically active radicals in biological tissues that alter the cell function or result in cell death. The AIR ER-2 flight measurements will enable scientists to study the radiation risk associated with the high-altitude operation of a commercial supersonic transport. The ER-2 radiation measurement flights will follow predetermined, carefully chosen courses to provide an appropriate database matrix which will enable the evaluation of predictive modeling techniques. Explicit scientific results such as dose rate, dose equivalent rate, magnetic cutoff, neutron flux, and air ionization rate associated with those flights are predicted by using the AIR model. Through these flight experiments, we will further increase our knowledge and understanding of the AIR environment and our ability to assess the risk from the associated hazard.

  1. Responses of epidermal cell turgor pressure and photosynthetic activity of leaves of the atmospheric epiphyte Tillandsia usneoides (Bromeliaceae) after exposure to high humidity.

    Science.gov (United States)

    Martin, Craig E; Rux, Guido; Herppich, Werner B

    2013-01-01

    It has been well-established that many epiphytic bromeliads of the atmospheric-type morphology, i.e., with leaf surfaces completely covered by large, overlapping, multicellular trichomes, are capable of absorbing water vapor from the atmosphere when air humidity increases. It is much less clear, however, whether this absorption of water vapor can hydrate the living cells of the leaves and, as a consequence, enhance physiological processes in such cells. The goal of this research was to determine if the absorption of atmospheric water vapor by the atmospheric epiphyte Tillandsia usneoides results in an increase in turgor pressure in leaf epidermal cells that subtend the large trichomes, and, by using chlorophyll fluorescence techniques, to determine if the absorption of atmospheric water vapor by leaves of this epiphyte results in increased photosynthetic activity. Results of measurements on living cells of attached leaves of this epiphytic bromeliad, using a pressure probe and of whole-shoot fluorescence imaging analyses clearly illustrated that the turgor pressure of leaf epidermal cells did not increase, and the photosynthetic activity of leaves did not increase, following exposure of the leaves to high humidity air. These results experimentally demonstrate, for the first time, that the absorption of water vapor following increases in atmospheric humidity in atmospheric epiphytic bromeliads is mostly likely a physical phenomenon resulting from hydration of non-living leaf structures, e.g., trichomes, and has no physiological significance for the plant's living tissues. Copyright © 2012 Elsevier GmbH. All rights reserved.

  2. Physical analysis of multivariate measurements in the Atmospheric high-energy physics experiments within ADEI platform

    International Nuclear Information System (INIS)

    Avakyan, K.; Chilingarian, A.; Karapetyan, T.; Chilingaryan, S.

    2017-01-01

    To make transformational scientific progress in Space science and geophysics, the Sun, heliosphere, magnetosphere and different layers of the atmosphere must be studied as a coupled system. Presented paper describes how information on complicated physical processes on Sun, in the heliosphere, magnetosphere and atmosphere can be made immediately assessable for researchers via advanced multivariate visualization system with simple statistical analysis package. Research of the high-energy phenomena in the atmosphere and the atmospheric discharges is of special importance. The relationship between thundercloud electrification, lightning activity, wideband radio emission and particle fluxes have not been yet unambiguously established. One of most intriguing opportunities opening by observation of the high-energy processes in the atmosphere is their relation to lightning initiation. Investigations of the accelerated structures in the geospace plasmas can as well shed light on particle acceleration up to much higher energies in the similar structures of space plasmas in the distant objects of the Universe. (author)

  3. Special Analysis: Atmospheric Dose Resulting from the Release of C14 from Reactor Moderator Deionizers in a Disposal Environment

    International Nuclear Information System (INIS)

    Hiergesell, Robert A.; Swingle, Robert F.

    2005-01-01

    The proposed action of disposing of 52 moderator deionizer vessels within the ILV was evaluated in this SA. In particular, a detailed analysis of the release of 14 C via the atmospheric pathway was conducted for these vessels since the major concern has been the nearly 20 Ci of 14 C that is associated with each vessel. The more rigorous evaluation of the atmospheric pathway for 14 C included incorporation of new information about the chemical availability of 14 C when disposed in a grout/cement encapsulation environment, as will be the case in the ILV. This information was utilized to establish the source term for a 1-D numerical model to simulate the diffusion of 14 CO 2 from the ILV Waste Zone to the land surface. The results indicate a peak surface emanation rate from the entire ILV of 1.42E-08 Ci/yr with an associated dose of only 3.83E-05 mrem/yr to the Maximally Exposed Individual (MEI) at 100m. The fact that the atmospheric pathway exposure for 14 C is controlled by chemical solubility limits for 14 C between the solid waste, pore water and pore vapor within the disposal environment rather than the absolute inventory suggests that the establishment of specific facility limits is inappropriate. With the relaxation of the atmospheric pathway restriction, the groundwater pathway becomes the more restrictive in terms of disposing 14 C or 14 C KB within the ILV. Since the resin-based 14 C of the 52 moderator deionizer vessels is highly similar to the 14 C KB waste form, the inventory from the 52 deionizer vessels is compared against the groundwater limits for that waste form. The small groundwater pathway fraction (1.14E-05) calculated for the proposed inventory of the 52 moderator deionizer vessels indicates that the proposed action will have an insignificant impact with respect to possible exposures via the groundwater pathway. This investigation recommends that there be no ILV Atmospheric pathway limit for 14 C and 14 C KB . Further, in the absence of an

  4. A simulation of the OMEGA/Mars Express observations: Analysis of the atmospheric contribution

    Science.gov (United States)

    Melchiorri, R.; Drossart, P.; Fouchet, T.; Bézard, B.; Forget, F.; Gendrin, A.; Bibring, J. P.; Manaud, N.; OMEGA Team; Berthé, M.; Bibring, J.-P.; Langevin, Y.; Forni, O.; Gendrin, A.; Gondet, B.; Manaud, N.; Poulet, F.; Poulleau, G.; Soufflot, A.; Mangold, N.; Bonello, G.; Forget, F.; Bezard, B.; Combes, M.; Drossart, P.; Encrenaz, T.; Fouchet, T.; Melchiorri, R.; Erard, S.; Bellucci, G.; Altieri, F.; Formisano, V.; Fonti, S.; Capaccioni, F.; Cerroni, P.; Coradini, A.; Kottsov, V.; Ignatiev, N.; Moroz, V.; Titov, D.; Zasova, L.; Pinet, P.; Schmitt, B.; Sotin, C.; Hauber, E.; Hoffmann, H.; Jaumann, R.; Keller, U.; Arvidson, R.; Mustard, J.; Duxbary, T.

    2006-08-01

    Spectral images of Mars obtained by the Mars Express/OMEGA experiment in the near infrared are the result of a complex combination of atmospheric, aerosol and ground features. Retrieving the atmospheric information from the data is important, not only to decorrelate mineralogical against atmospheric features, but also to retrieve the atmospheric variability. Once the illumination conditions have been taken into account, the main source of variation on the CO2 absorption is due to the altitude of the surface, which governs atmospheric pressure variation by more than an order of magnitude between the summit of Olympus Mons down to the bottom of Valles Marineris. In this article we present a simplified atmospheric spectral model without scattering, specially developed for the OMEGA observations, which is used to retrieve the local topography through the analysis of the 2.0μmCO2 band. OMEGA atmospheric observations increase the horizontal resolution compared to MOLA altimetry measurements, and therefore complement the mineralogical studies from the same instrument. Finally, residual variations of the pressure can be related to atmospheric structure variation.

  5. Multielement characterization of atmospheric pollutants by x-ray fluorescence analysis and instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Rancitelli, L.A.; Tanner, T.M.

    1976-01-01

    The simultaneous measurement of a wide spectrum of elements in aerosols collected on air filters and in rainwater can yield information on the origin, transport, and removal of atmospheric pollutants. In order to determine the elemental content of these aerosols, a pair of highly sensitive, precise and complementing instrumental techniques, x-ray fluorescence and neutron activation analysis, have been developed and employed. Data are presented on the results of combined x-ray fluorescence and activation analysis of aerosols collected in a number of urban areas of the USA and from the 80th median sampling network in March 1972. From a comparison of these ratios in granite and diabase with those of filters placed in urban areas, it is evident that Zn, Se, Sb, Hg, and Pb levels have been increased by as much as several orders of magnitude. Al, Co, La, Fe, Eu, Sm, Tb, Ta, Hf, and Th appear to exist at levels compatible with an earth's crust origin

  6. Hydrocarbon analysis using desorption atmospheric pressure chemical ionization

    KAUST Repository

    Jjunju, Fred Paul Mark; Badu-Tawiah, Abraham K.; Li, Anyin; Soparawalla, Santosh; Roqan, Iman S.; Cooks, Robert Graham

    2013-01-01

    Characterization of the various petroleum constituents (hydronaphthalenes, thiophenes, alkyl substituted benzenes, pyridines, fluorenes, and polycyclic aromatic hydrocarbons) was achieved under ambient conditions without sample preparation by desorption atmospheric pressure chemical ionization (DAPCI). Conditions were chosen for the DAPCI experiments to control whether ionization was by proton or electron transfer. The protonated molecule [M+H]+ and the hydride abstracted [MH]+ form were observed when using an inert gas, typically nitrogen, to direct a lightly ionized plasma generated by corona discharge onto the sample surface in air. The abundant water cluster ions generated in this experiment react with condensed-phase functionalized hydrocarbon model compounds and their mixtures at or near the sample surface. On the other hand, when naphthalene was doped into the DAPCI gas stream, its radical cation served as a charge exchange reagent, yielding molecular radical cations (M+) of the hydrocarbons. This mode of sample ionization provided mass spectra with better signal/noise ratios and without unwanted side-products. It also extended the applicability of DAPCI to petroleum constituents which could not be analyzed through proton transfer (e.g., higher molecular PAHs such as chrysene). The thermochemistry governing the individual ionization processes is discussed and a desorption/ionization mechanism is inferred. © 2012 Elsevier B.V.

  7. Global Analysis of Climate Change Projection Effects on Atmospheric Rivers

    Science.gov (United States)

    Espinoza, Vicky; Waliser, Duane E.; Guan, Bin; Lavers, David A.; Ralph, F. Martin

    2018-05-01

    A uniform, global approach is used to quantify how atmospheric rivers (ARs) change between Coupled Model Intercomparison Project Phase 5 historical simulations and future projections under the Representative Concentration Pathway (RCP) 4.5 and RCP8.5 warming scenarios. The projections indicate that while there will be 10% fewer ARs in the future, the ARs will be 25% longer, 25% wider, and exhibit stronger integrated water vapor transports (IVTs) under RCP8.5. These changes result in pronounced increases in the frequency (IVT strength) of AR conditions under RCP8.5: 50% (25%) globally, 50% (20%) in the northern midlatitudes, and 60% (20%) in the southern midlatitudes. The models exhibit systematic low biases across the midlatitudes in replicating historical AR frequency ( 10%), zonal IVT ( 15%), and meridional IVT ( 25%), with sizable intermodel differences. A more detailed examination of six regions strongly impacted by ARs suggests that the western United States, northwestern Europe, and southwestern South America exhibit considerable intermodel differences in projected changes in ARs.

  8. Hydrocarbon analysis using desorption atmospheric pressure chemical ionization

    KAUST Repository

    Jjunju, Fred Paul Mark

    2013-07-01

    Characterization of the various petroleum constituents (hydronaphthalenes, thiophenes, alkyl substituted benzenes, pyridines, fluorenes, and polycyclic aromatic hydrocarbons) was achieved under ambient conditions without sample preparation by desorption atmospheric pressure chemical ionization (DAPCI). Conditions were chosen for the DAPCI experiments to control whether ionization was by proton or electron transfer. The protonated molecule [M+H]+ and the hydride abstracted [MH]+ form were observed when using an inert gas, typically nitrogen, to direct a lightly ionized plasma generated by corona discharge onto the sample surface in air. The abundant water cluster ions generated in this experiment react with condensed-phase functionalized hydrocarbon model compounds and their mixtures at or near the sample surface. On the other hand, when naphthalene was doped into the DAPCI gas stream, its radical cation served as a charge exchange reagent, yielding molecular radical cations (M+) of the hydrocarbons. This mode of sample ionization provided mass spectra with better signal/noise ratios and without unwanted side-products. It also extended the applicability of DAPCI to petroleum constituents which could not be analyzed through proton transfer (e.g., higher molecular PAHs such as chrysene). The thermochemistry governing the individual ionization processes is discussed and a desorption/ionization mechanism is inferred. © 2012 Elsevier B.V.

  9. Surface analysis of 316 stainless steel treated with cold atmospheric plasma

    Energy Technology Data Exchange (ETDEWEB)

    Williams, David F., E-mail: david.williams@surrey.ac.uk [Department of Mechanical Engineering Sciences, University Of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); TWI Ltd Granta Park Great Abington, Cambridge CB21 6AL (United Kingdom); Kellar, Ewen J.C. [TWI Ltd Granta Park Great Abington, Cambridge CB21 6AL (United Kingdom); Jesson, David A.; Watts, John F. [Department of Mechanical Engineering Sciences, University Of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

    2017-05-01

    Highlights: • Reduction in carbon contamination from ∼80 at.% to 40 at.% after 15 s treatment. • Associated carbon thickness reduction from 4.5 nm to 0.5 nm. • Area treated by torch has a diameter of 11 mm measured using imaging XPS. - Abstract: The surface of 316 stainless steel has been modified using cold atmospheric plasma (CAP) to increase the surface free energy (by cleaning the and chemically activating the surface)IN preparation for subsequent processes such as painting, coating or adhesive bonding. The analyses carried out, on CAP treated 316 stainless steel surfaces, includes X-ray photoelectron spectroscopy (XPS), imaging XPS (iXPS), and surface free energy (SFE) analysis using contact angle measurements. The CAP treatment is shown to increase the SFE of as-received 316 stainless steel from ∼39 mJ m{sup −1} to >72 mJ m{sup −1} after a short exposure to the plasma torch. This was found to correlate to a reduction in adventitious carbon, as determined by XPS analysis of the surface. The reduction from ∼90 at% to ∼30% and ∼39 at%, after being plasma treated for 5 min and 15 s respectively, shows that the process is relatively quick at changing the surface. It is suggested that the mechanism that causes the increase in surface free energy is chain scission of the hydrocarbon contamination triggered by free electrons in the plasma plume followed by chemical functionalisation of the metal oxide surface and some of the remaining carbon contamination layer.

  10. Thermal Analysis of the Decomposition of Ammonium Uranyl Carbonate (AUC) in Different Atmospheres

    DEFF Research Database (Denmark)

    Hälldahl, L.; Sørensen, Ole Toft

    1979-01-01

    The intermediate products formed during thermal decomposition of ammonium uranyl carbonate (AUC) in different atmospheres, (air, helium and hydrogen) have been determined by thermal analysis, (TG, and DTA) and X-ray analysis. The endproducts observed are U3O8 and UO2 in air/He and hydrogen, respe......, respectively. The following intermediate products were observed in all atmospheres: http://www.sciencedirect.com.globalproxy.cvt.dk/cache/MiamiImageURL/B6THV-44K80TV-FB-1/0?wchp=dGLzVlz-zSkWW X-ray diffraction analysis showed that these phases were amorphous....

  11. Use of neutron activation analysis at the IBR-2 reactor for atmospheric monitoring

    International Nuclear Information System (INIS)

    Peresedov, V.F.; Ostrovnaya, T.M.; Strelkova, L.P.; Chinaeva, V.P.; Gundorina, S.F.

    1999-01-01

    The object of this work was the study of the possibilities of neutron activation analysis (NAA) for determination of elemental content of atmospheric aerosol. On examples of three Siberian regions it was shown that methodics of analysis allow to estimate the average level of suburban background (ALSB), scale of its regional, season and annual changes. Analysis of enrichment factors allows one to convince in presence of increased content of a row of heavy metals in atmospheric air of background regions what is the consequence of a global growing of technogenic impact

  12. Atmospheric thorium pollution and inhalation exposure in the largest rare earth mining and smelting area in China.

    Science.gov (United States)

    Wang, Lingqing; Zhong, Buqing; Liang, Tao; Xing, Baoshan; Zhu, Yifang

    2016-12-01

    Exposure to radionuclide thorium (Th) has generated widespread public concerns, mainly because of its radiological effects on human health. Activity levels of airborne 232 Th in total suspended particulate (TSP) were measured in the vicinity of the largest rare earth mine in China in August 2012 and March 2013. The mean activity concentrations of 232 Th in TSP ranged from 820μBqm -3 in a mining area in August 2012 to 39,720μBqm -3 in a smelting area in March 2013, much higher than the world reference of 0.5μBqm -3 . Multistatistical analysis and Kohonen's self-organizing maps suggested that 232 Th in TSP was mainly derived from rare earth mining and smelting practices. In addition, personal inhalation exposures to 232 Th associated with respirable particulate (PM 10 ) were also measured among local dwellers via personal monitoring. The mean dose values for different age groups in the smelting and mining areas ranged from 97.86 to 417μSvyear - 1 and from 101.03 to 430.83μSvyear -1 , respectively. These results indicate that people living in the study areas are exposed to high levels of widespread 232 Th. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. PIXE analysis of atmospheric particulate matter in glas fibre filters

    International Nuclear Information System (INIS)

    Tabacniks, M.H.; Orsini, C.Q.; Maenhaut, W.

    1993-01-01

    A 3-step extraction procedure was developed to allow particle-induced X-ray emission (PIXE) analysis of particulate matter in normal glass fibre filter samples. The detection limits, expressed in ng/m 3 of air, for the filter extracts were 5 to 30 times lower than those achieved by PIXE analysis or ordinary Nuclepore polycarbonate filter samples. The concentration results were compared with those obtained from routine atomic absorption spectrometry measurements and with the PIXE data from Nuclepore stacked filter unit samples taken in parallel. (orig.)

  14. Air crew exposure to cosmic radiation. New analysis, recommendations EURADOS

    Energy Technology Data Exchange (ETDEWEB)

    Spurny, F; Votockova, I [Academy of the Sciences of Czech Republic, Prague (Czech Republic). Nuclear Physics Institute, Department of Radiation Dosimetry

    1996-12-31

    Cosmic radiation on the board of an aircraft consist of two components: directly ionizing radiation (electron, proton - low LET) and neutrons (high LET). Neither composition nor the energy spectrum of usual on-Earth calibration sources ({sup 60}Co, {sup 252}Cf) do not correspond to the field on a board. Therefore high energy reference fields behind shielding high energy accelerator at CERN and Dubna have been created and intensively studied. Their typical characteristics following from the results of our measurements were obtained. In-flight measurements on the board of commercial aircraft have been realized since 1991 during about 20 flights, Flight routes extended from the 1.3 grad N up to about 65 grad N, flying altitudes varied from 8.2 km to 12.5 km. The exposure level due to galactic cosmic radiation is inversely proportional to the solar activity. Some radiation protection aspects were concluded: (a) The usual limits of annual air crew flight hours correspond at 11.3 km to about 4 mSv per year, with new ICRP conversion factors to about 5 mSv per year; (b) Monthly flight hours limit does not exclude that the exposure of a pregnant women can exceed 1 mSv during this period; (c) The air crew exposure should therefore be checked, controlled a nd administered as conscientiously as for any other group of occupationally exposed persons. A Working group 11 of EURADOS `Exposure of air crew to cosmic radiation` has been formed (1992-1995) to prepare basic analysis and recommendations concerning the topics. (Abstract Truncated)

  15. The role of neutron activation analysis for trace elements characterization, analysis and certification in atmospheric particulates

    International Nuclear Information System (INIS)

    Rizzio, Enrico; Gallorini, Mario

    2002-01-01

    The Neutron Activation Analysis (NAA) owns these requirements and is universally accepted as one of the most reliable analytical tools for trace and ultratrace elements determination. Its use in trace elements atmospheric pollution related studies has been and is still extensive as can be demonstrate by several specific works and detailed reviews. In this work, the application of this nuclear technique, in solving a series of different analytical problems related to trace elements in air pollution processes is reported. Examples and results are given on the following topics: characterization of urban and rural airborne particulate samples; particles size distribution in the different inhalable and respirable fractions (PM10 and PM 2.5); certification of related Standard Reference Materials for data quality assurance. (author)

  16. Relating landfill gas emissions to atmospheric pressure using numerical modeling and state-space analysis

    DEFF Research Database (Denmark)

    Poulsen, T.G.; Christophersen, Mette; Moldrup, P.

    2003-01-01

    were applied: (I) State-space analysis was used to identify relations between gas flux and short-term (hourly) variations in atmospheric pressure. (II) A numerical gas transport model was fitted to the data and used to quantify short-term impacts of variations in atmospheric pressure, volumetric soil......-water content, soil gas permeability, soil gas diffusion coefficients, and biological CH4 degradation rate upon landfill gas concentration and fluxes in the soil. Fluxes and concentrations were found to be most sensitive to variations in volumetric soil water content, atmospheric pressure variations and gas...... permeability whereas variations in CH4 oxidation rate and molecular coefficients had less influence. Fluxes appeared to be most sensitive to atmospheric pressure at intermediate distances from the landfill edge. Also overall CH4 fluxes out of the soil over longer periods (years) were largest during periods...

  17. Influence factor analysis of atmospheric electric field monitoring near ground under different weather conditions

    International Nuclear Information System (INIS)

    Wan, Haojiang; Wei, Guanghui; Cui, Yaozhong; Chen, Yazhou

    2013-01-01

    Monitoring of atmospheric electric field near ground plays a critical role in atmospheric environment detecting and lightning warning. Different environmental conditions (e.g. buildings, plants, weather, etc.) have different influences on the data's coherence in an atmospheric electric field detection network. In order to study the main influence factors of atmospheric electric field monitoring under different weather conditions, with the combination of theoretical analysis and experiments, the electric field monitoring data on the ground and on the top of a building are compared in fair weather and thunderstorm weather respectively in this paper. The results show that: In fair weather, the field distortion due to the buildings is the main influence factor on the electric field monitoring. In thunderstorm weather, the corona ions produced from the ground, besides the field distortion due to the buildings, can also influence the electric field monitoring results.

  18. Preliminary analysis of a membrane-based atmosphere-control subsystem

    Science.gov (United States)

    Mccray, Scott B.; Newbold, David D.; Ray, Rod; Ogle, Kathryn

    1993-01-01

    Controlled ecological life supprot systems will require subsystems for maintaining the consentrations of atmospheric gases within acceptable ranges in human habitat chambers and plant growth chambers. The goal of this work was to develop a membrane-based atmosphere comntrol (MBAC) subsystem that allows the controlled exchange of atmospheric componets (e.g., oxygen, carbon dioxide, and water vapor) between these chambers. The MBAC subsystem promises to offer a simple, nonenergy intensive method to separate, store and exchange atmospheric components, producing optimal concentrations of components in each chamber. In this paper, the results of a preliminary analysis of the MBAC subsystem for control of oxygen and nitrogen are presented. Additionally, the MBAC subsystem and its operation are described.

  19. Occupational exposure to HDI: progress and challenges in biomarker analysis.

    Science.gov (United States)

    Flack, Sheila L; Ball, Louise M; Nylander-French, Leena A

    2010-10-01

    1,6-Hexamethylene diisocyanate (HDI) is extensively used in the automotive repair industry and is a commonly reported cause of occupational asthma in industrialized populations. However, the exact pathological mechanism remains uncertain. Characterization and quantification of biomarkers resulting from HDI exposure can fill important knowledge gaps between exposure, susceptibility, and the rise of immunological reactions and sensitization leading to asthma. Here, we discuss existing challenges in HDI biomarker analysis including the quantification of N-acetyl-1,6-hexamethylene diamine (monoacetyl-HDA) and N,N'-diacetyl-1,6-hexamethylene diamine (diacetyl-HDA) in urine samples based on previously established methods for HDA analysis. In addition, we describe the optimization of reaction conditions for the synthesis of monoacetyl-HDA and diacetyl-HDA, and utilize these standards for the quantification of these metabolites in the urine of three occupationally exposed workers. Diacetyl-HDA was present in untreated urine at 0.015-0.060 μg/l. Using base hydrolysis, the concentration range of monoacetyl-HDA in urine was 0.19-2.2 μg/l, 60-fold higher than in the untreated samples on average. HDA was detected only in one sample after base hydrolysis (0.026 μg/l). In contrast, acid hydrolysis yielded HDA concentrations ranging from 0.36 to 10.1 μg/l in these three samples. These findings demonstrate HDI metabolism via N-acetylation metabolic pathway and protein adduct formation resulting from occupational exposure to HDI. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Hanford Site Composite Analysis Technical Approach Description: Atmospheric Transport Modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Sun, B. [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Lehman, L. L. [CH2M HILL Plateau Remediation Company, Richland, WA (United States)

    2017-10-02

    The U.S. Department of Energy (DOE) in DOE O 435.1 Chg. 1, Radioactive Waste Management, requires the preparation and maintenance of a composite analysis (CA). The primary purpose of the CA is to provide a reasonable expectation that the primary public dose limit is not likely to be exceeded by multiple source terms that may significantly interact with plumes originating at a low-level waste disposal facility. The CA is used to facilitate planning and land use decisions that help assure disposal facility authorization will not result in long-term compliance problems; or, to determine management alternatives, corrective actions or assessment needs, if potential problems are identified.

  1. Occupational Radiation Exposure Analysis of US ITER DCLL TBM

    Energy Technology Data Exchange (ETDEWEB)

    Merrill, Brad J; Cadwallader, Lee C; Dagher, Mohamad

    2007-08-01

    This report documents an Occupational Radiation Exposure (ORE) analysis that was performed for the US International Thermonuclear Experimental Reactor (ITER) Dual Coolant Lead Lithium (DCLL) Test Blanket Module (TBM). This analysis was performed with the QADMOD dose code for anticipated maintenance activities for this TBM concept and its ancillary systems. The QADMOD code was used to model the PbLi cooling loop of this TBM concept by specifying gamma ray source terms that simulated radioactive material within the piping, valves, heat exchanger, permeator, pump, drain tank, and cold trap of this cooling system. Estimates of the maintenance tasks that will have to be performed and the time required to perform these tasks where developed based on either expert opinion or on industrial maintenance experience for similar technologies. This report details the modeling activity and the calculated doses for the maintenance activities envisioned for the US DCLL TBM.

  2. Model Titan atmospheric hydrocarbon analysis by Ion Mobility Spectrometry in dry helium

    International Nuclear Information System (INIS)

    Kojiro, D.R.; Stimac, R.M.; Wernlund, R.F.; Cohen, M.J.

    1990-01-01

    Ion Mobility Spectrometry (IMS) is one analytical technique being investigated for the in situ analysis of the atmosphere of Titan. Any hydrocarbon ions that may form react immediately, in microseconds, with the high concentration of water vapor normally present in conventional IMS. By reducing the water concentration to the parts-per-billion range, the lifetime of the hydrocarbon ions may be increased to the milliseconds required for measurement. At low water level concentrations, other species may become the reactant ion. This study focuses on IMS analysis of expected Titan atmospheric hydrocarbons under very dry, low water concentration conditions

  3. Assessment of exposure to atmospheric particles: contribution of individual measurements; Evaluation de l'exposition aux particules atmospheriques: apport des mesures individuelles

    Energy Technology Data Exchange (ETDEWEB)

    Mosqueron, L.; Momas, I. [Universite Rene Descartes, Faculte des Sciences Pharmaceutiques et Biologiques, Lab. d' Hygiene et de Sante Publique, 75 - Paris (France); Le Moullec, Y. [Laboratoire d' Hygiene de la Ville de Paris, 75 (France); Momas, I. [Direction de l' Action Sociale, de l' Enfance et de la Sante, Cellule Epidemiologie, 75 - Paris (France)

    2001-02-01

    There are few studies of individual exposure to atmospheric particles, because of the relatively bulky and noisy sampling devices. These personalized measurements, generally associated with micro-environmental measurements, are aimed at studying the distribution of individual exposure and identifying its main determinants. Methods: A synopsis of the methods implemented in such studies (populations studied, measurements strategies, questionnaires on time-activity patterns, residences and work place) was detailed. The major results are presented and discussed from an epidemiological point of view. Results: The individual exposure measured with portable devices generally were generally found to be higher than the estimations made by combining micro-environmental (outdoor and indoor) measurements and data from time-activity diaries. The difference between results of these two approaches, known as 'personal cloud', remains poorly understood. Correlations between individual measurements and outdoor concentrations are weak; nevertheless, day to day variations of these two series of measurements are better related. The main determinants of individual exposure to particles are identified but a quantification of their contribution remains difficult, except for passive smoking. Conclusion: Personal measurements cannot be used to estimate particle exposure in large scale epidemiological studies. This exposure needs to be modeled. (authors)

  4. Radionuclide dispersion in the atmosphere

    International Nuclear Information System (INIS)

    Moura Neto, C. de; Amorim, E.S. do; Panetta, J.

    1979-05-01

    The instantaneous liberation of radionuclides in the atmosphere is studied in three dimensions, according to the formalism of the diffusion theory. The analytical solution, expose to gravitational and an atmospherical effects, is combined with the discretization of space and time in the calculation of levels of exposure. A typical inventory (for a PWR) was considered in the calculation of immersion doses, and the results permitted a comparative analysis among the different existing models. (Author) [pt

  5. Analysis and application of Fourier transform spectroscopy in atmospheric remote sensing

    Science.gov (United States)

    Park, J. H.

    1984-01-01

    An analysis method for Fourier transform spectroscopy is summarized with applications to various types of distortion in atmospheric absorption spectra. This analysis method includes the fast Fourier transform method for simulating the interferometric spectrum and the nonlinear least-squares method for retrieving the information from a measured spectrum. It is shown that spectral distortions can be simulated quite well and that the correct information can be retrieved from a distorted spectrum by this analysis technique.

  6. KNOW YOUR NEIGHBORHOOD: A DETAILED MODEL ATMOSPHERE ANALYSIS OF NEARBY WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Giammichele, N.; Bergeron, P. [Kitt Peak National Observatory, National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation (United States); Dufour, P., E-mail: noemi.giammichele@astro.umontreal.ca, E-mail: pierre.bergeron@astro.umontreal.ca, E-mail: patrick.dufour@astro.umontreal.ca [Departement de Physique, Universite de Montreal, C.P. 6128, Succ. Centre-Ville, Montreal, Quebec H3C 3J7 (Canada)

    2012-04-01

    We present improved atmospheric parameters of nearby white dwarfs lying within 20 pc of the Sun. The aim of the current study is to obtain the best statistical model of the least-biased sample of the white dwarf population. A homogeneous analysis of the local population is performed combining detailed spectroscopic and photometric analyses based on improved model atmosphere calculations for various spectral types including DA, DB, DC, DQ, and DZ stars. The spectroscopic technique is applied to all stars in our sample for which optical spectra are available. Photometric energy distributions, when available, are also combined to trigonometric parallax measurements to derive effective temperatures, stellar radii, as well as atmospheric compositions. A revised catalog of white dwarfs in the solar neighborhood is presented. We provide, for the first time, a comprehensive analysis of the mass distribution and the chemical distribution of white dwarf stars in a volume-limited sample.

  7. NASA's Upper Atmosphere Research Program UARP and Atmospheric Chemistry Modeling and Analysis Program (ACMAP): Research Summaries 1994 - 1996. Report to Congress and the Environmental Protection Agency

    Science.gov (United States)

    Kendall, Rose (Compiler); Wolfe, Kathy (Compiler)

    1997-01-01

    Under the mandate contained in the FY 1976 NASA Authorization Act, the National Aeronautics and Space Administration (NASA) has developed and is implementing a comprehensive program of research, technology, and monitoring of the Earth's upper atmosphere, with emphasis on the stratosphere. This program aims at expanding our understanding to permit both the quantitative analysis of current perturbations as well as the assessment of possible future changes in this important region of our environment. It is carried out jointly by the Upper Atmosphere Research Program (UARP) and the Atmospheric Chemistry Modeling and Analysis Program (ACMAP), both managed within the Science Division in the Office of Mission to Planet Earth at NASA. Significant contributions to this effort are also provided by the Atmospheric Effects of Aviation Project (AEAP) of NASA's Office of Aeronautics. The long-term objectives of the present program are to perform research to: understand the physics, chemistry, and transport processes of the upper atmosphere and their effect on the distribution of chemical species in the stratosphere, such as ozone; understand the relationship of the trace constituent composition of the lower stratosphere and the lower troposphere to the radiative balance and temperature distribution of the Earth's atmosphere; and accurately assess possible perturbations of the upper atmosphere caused by human activities as well as by natural phenomena. In compliance with the Clean Air Act Amendments of 1990, Public Law 101-549, NASA has prepared a report on the state of our knowledge of the Earth's upper atmosphere, particularly the stratosphere, and on the progress of UARP and ACMAP. The report for the year 1996 is composed of two parts. Part 1 summarizes the objectives, status, and accomplishments of the research tasks supported under NASA UARP and ACMAP in a document entitled, Research Summary 1994-1996. Part 2 is entitled Present State of Knowledge of the Upper Atmosphere

  8. Air crew exposure to cosmic radiation. New analysis, recommendations EURADOS

    International Nuclear Information System (INIS)

    Spurny, F.; Votockova, I.

    1995-01-01

    Cosmic radiation on the board of an aircraft consist of two components: directly ionizing radiation (electron, proton - low LET) and neutrons (high LET). Neither composition nor the energy spectrum of usual on-Earth calibration sources ( 60 Co, 252 Cf) do not correspond to the field on a board. Therefore high energy reference fields behind shielding high energy accelerator at CERN and Dubna have been created and intensively studied. Their typical characteristics following from the results of our measurements were obtained. In-flight measurements on the board of commercial aircraft have been realized since 1991 during about 20 flights, Flight routes extended from the 1.3 grad N up to about 65 grad N, flying altitudes varied from 8.2 km to 12.5 km. The exposure level due to galactic cosmic radiation is inversely proportional to the solar activity. Some radiation protection aspects were concluded: (a) The usual limits of annual air crew flight hours correspond at 11.3 km to about 4 mSv per year, with new ICRP conversion factors to about 5 mSv per year; (b) Monthly flight hours limit does not exclude that the exposure of a pregnant women can exceed 1 mSv during this period; (c) The air crew exposure should therefore be checked, controlled a nd administered as conscientiously as for any other group of occupationally exposed persons. A Working group 11 of EURADOS 'Exposure of air crew to cosmic radiation' has been formed (1992-1995) to prepare basic analysis and recommendations concerning the topics. The basic recommendations are the following: (a) air crew flying routinely at altitudes over 8 km are deemed to be category B workers, it is therefore important to estimate, record, control and, where necessary, to limit the doses; (b) the preferred procedure in order to estimate doses to air crew or frequent flyers is to determine route doses and fold these data with data on staff rostering; (c) where doses may exceed the limit for category B workers (6 mSv per year), on

  9. Joint analysis of French and Czech uranium miners: lung cancer risk at low radon exposure rates and modifying effects of time since exposure and age at exposure

    International Nuclear Information System (INIS)

    Ladislav Tomasek; Agnes Rogel; Margot Tirmarche; Dominique Laurier

    2006-01-01

    The present analysis was conducted in the frame of European project 'Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiologic and experimental data'. The overall goal of the project related to uranium miners was the evaluation of lung cancer dose-response relationship and of dose rate effects among European uranium miners exposed to low doses and low dose rates of radon decay products. In addition, modifying factors like attained age, age at exposure and time since exposure were investigated. The joint analysis of French and Czech uranium miners was conducted mainly in order to increase the statistical power and to allow a more detailed description of the variation of dose-response relationship in time. (N.C.)

  10. Joint analysis of French and Czech uranium miners: lung cancer risk at low radon exposure rates and modifying effects of time since exposure and age at exposure

    Energy Technology Data Exchange (ETDEWEB)

    Ladislav Tomasek [National Radiation Protection Institute, Prague (Czech Republic); Agnes Rogel; Margot Tirmarche; Dominique Laurier [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France)

    2006-07-01

    The present analysis was conducted in the frame of European project 'Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiologic and experimental data'. The overall goal of the project related to uranium miners was the evaluation of lung cancer dose-response relationship and of dose rate effects among European uranium miners exposed to low doses and low dose rates of radon decay products. In addition, modifying factors like attained age, age at exposure and time since exposure were investigated. The joint analysis of French and Czech uranium miners was conducted mainly in order to increase the statistical power and to allow a more detailed description of the variation of dose-response relationship in time. (N.C.)

  11. Human performance analysis of industrial radiography radiation exposure events

    International Nuclear Information System (INIS)

    Reece, W.J.; Hill, S.G.

    1995-01-01

    A set of radiation overexposure event reports were reviewed as part of a program to examine human performance in industrial radiography for the US Nuclear Regulatory Commission. Incident records for a seven year period were retrieved from an event database. Ninety-five exposure events were initially categorized and sorted for further analysis. Descriptive models were applied to a subset of severe overexposure events. Modeling included: (1) operational sequence tables to outline the key human actions and interactions with equipment, (2) human reliability event trees, (3) an application of an information processing failures model, and (4) an extrapolated use of the error influences and effects diagram. Results of the modeling analyses provided insights into the industrial radiography task and suggested areas for further action and study to decrease overexposures

  12. On the 485-day Mode in the Atmospheric Angular Momentum: Spectral Analysis of IERS Data

    Science.gov (United States)

    Tsurkis, I. Ya.; Kuchai, M. S.

    2018-05-01

    The modification of spectral analysis especially intended for studying the disturbing functions of the atmosphere and ocean, as well as the observed polar motion (Wiener-Liouville spectrum), is used. The time series of the atmospheric disturbing functions obtained by the U.S. National Centers for Environmental Prediction (NCEP) of the International Earth Rotation and Reference Systems Service (IERS) for the period from January 1, 1980 to June 20, 2014 (http://www.iers.org/.cs1?pid=43-1100116) are analyzed. It is shown that the baric disturbing function contains a regular mode with a period of 16 months; the contribution of this mode in the polar motion is estimated.

  13. GEOSPATIAL ANALYSIS OF ATMOSPHERIC HAZE EFFECT BY SOURCE AND SINK LANDSCAPE

    Directory of Open Access Journals (Sweden)

    T. Yu

    2017-09-01

    Full Text Available Based on geospatial analysis model, this paper analyzes the relationship between the landscape patterns of source and sink in urban areas and atmospheric haze pollution. Firstly, the classification result and aerosol optical thickness (AOD of Wuhan are divided into a number of square grids with the side length of 6 km, and the category level landscape indices (PLAND, PD, COHESION, LPI, FRAC_MN and AOD of each grid are calculated. Then the source and sink landscapes of atmospheric haze pollution are selected based on the analysis of the correlation between landscape indices and AOD. Next, to make the following analysis more efficient, the indices selected before should be determined through the correlation coefficient between them. Finally, due to the spatial dependency and spatial heterogeneity of the data used in this paper, spatial autoregressive model and geo-weighted regression model are used to analyze atmospheric haze effect by source and sink landscape from the global and local level. The results show that the source landscape of atmospheric haze pollution is the building, and the sink landscapes are shrub and woodland. PLAND, PD and COHESION are suitable for describing the atmospheric haze effect by source and sink landscape. Comparing these models, the fitting effect of SLM, SEM and GWR is significantly better than that of OLS model. The SLM model is superior to the SEM model in this paper. Although the fitting effect of GWR model is more unsuited than that of SLM, the influence degree of influencing factors on atmospheric haze of different geography can be expressed clearer. Through the analysis results of these models, following conclusions can be summarized: Reducing the proportion of source landscape area and increasing the degree of fragmentation could cut down aerosol optical thickness; And distributing the source and sink landscape evenly and interspersedly could effectively reduce aerosol optical thickness which represents

  14. Geospatial Analysis of Atmospheric Haze Effect by Source and Sink Landscape

    Science.gov (United States)

    Yu, T.; Xu, K.; Yuan, Z.

    2017-09-01

    Based on geospatial analysis model, this paper analyzes the relationship between the landscape patterns of source and sink in urban areas and atmospheric haze pollution. Firstly, the classification result and aerosol optical thickness (AOD) of Wuhan are divided into a number of square grids with the side length of 6 km, and the category level landscape indices (PLAND, PD, COHESION, LPI, FRAC_MN) and AOD of each grid are calculated. Then the source and sink landscapes of atmospheric haze pollution are selected based on the analysis of the correlation between landscape indices and AOD. Next, to make the following analysis more efficient, the indices selected before should be determined through the correlation coefficient between them. Finally, due to the spatial dependency and spatial heterogeneity of the data used in this paper, spatial autoregressive model and geo-weighted regression model are used to analyze atmospheric haze effect by source and sink landscape from the global and local level. The results show that the source landscape of atmospheric haze pollution is the building, and the sink landscapes are shrub and woodland. PLAND, PD and COHESION are suitable for describing the atmospheric haze effect by source and sink landscape. Comparing these models, the fitting effect of SLM, SEM and GWR is significantly better than that of OLS model. The SLM model is superior to the SEM model in this paper. Although the fitting effect of GWR model is more unsuited than that of SLM, the influence degree of influencing factors on atmospheric haze of different geography can be expressed clearer. Through the analysis results of these models, following conclusions can be summarized: Reducing the proportion of source landscape area and increasing the degree of fragmentation could cut down aerosol optical thickness; And distributing the source and sink landscape evenly and interspersedly could effectively reduce aerosol optical thickness which represents atmospheric haze

  15. Bulky PAH-DNA induced by exposure of a co-culture model of human alveolar macrophages and embryonic epithelial cells to atmospheric particulate pollution

    International Nuclear Information System (INIS)

    Abbas, Imane; Garcon, Guillaume; Billet, Sylvain; Shirali, Pirouz; Andre, Veronique; Le Goff, Jeremie; Sichel, Francois; Roy Saint-Georges, Francoise; Mulliez, Philippe

    2012-01-01

    Because of their deep penetration in human lungs, fine airborne particulate matter were described as mainly responsible for the deleterious effects of exposure to air pollution on health. Organic constituents are adsorbed on particles surface and, after inhalation, some (polycyclic aromatic hydrocarbons, PAHs) can be activated into reactive metabolites and can bind to DNA. The formation of bulky DNA adducts has been researched after exposure of mono-and co-cultures of alveolar macrophages (AM) and human embryonic human lung epithelial (L132), to fine air pollution particulate matter Air samples have been collected with cascade impactor and characterized: size distribution (92.15% 2 /g), inorganic (Fe, AI, Ca, Na, K, Mg, Pb, etc.) and organic compounds (PAHs, etc.). 32 P post-labeling method was applied to detect bulky DNA adducts in AM and L132, in mono-and co-cultures, 72 h after their exposure to atmospheric particles at their Lethals and Effects concentrations or (LC or CE) to 50% (i.e. MA: EC 50 = 74.63 μg/mL and L132: LC-5-0 = 75.36 μg/mL). Exposure to desorbed particles (MA: C1= 61.11 μg/mL and L132 : C2 = 61.71 μg/mL) and B[a]P (1 μM) were included. Bulky PAH-DNA adducts were detected in AM in mono-culture after exposure to total particles (Pt), to B[a]P and desorbed particles (Pd). Whatever the exposure, no DNA adduct was detected in L132 in mono-culture. These results are coherent with the enzymatic activities of cytochrome P450 l Al in AM and L132. Exposure of co-culture to Pt, or Pd induced bulky adducts to DNA in AM but not in L132. Exposure to B[a]P alone has altered the DNA of AM and L132, in co-culture. Exposure to Pt is closer to the environmental conditions, but conferred an exposure to amounts of genotoxic agents compared to studies using organic extracts. The formation of bulky DNA adducts was nevertheless observed in AM exposed to Pt, in mono- or co-culture, indicating that they were competent in terms of metabolic activation of PAHs. The

  16. The health abnormalities under the technogenic exposures risks analysis

    Science.gov (United States)

    Fedorova, E. V.; Malyshev, V. S.; Borovkova, A. M.

    2017-11-01

    A number of the medico-ecological orientation subjects are included in the curricula of the masters being trained in the teaching course 13.04.02 “Power industry and electrical equipment” and had elected the courses “Anthropogenic safety in power industry and electrical equipment” of the engineering ecology and labor safety department (EE and LS) of NRU “MPEI”. The anthropogenic safety specialist is to know all consequences suffers of such disciplines on account of the human person being influenced with the anthropogenic stress firstly. Energetic is to be obviously foreground in the environment pollution. Carbon, sulfurs, nitrogen oxides, heavy metals compounds, soot particles, benzapiren are arrived to the atmospheric air. The receipt of the harmful substances with an inhaled air leads to the respiratory organs pathology, organism adaptation properties tension and the population morbidity increase. The discipline “The Human physiology” developed on EE and LS chair and being taught of the first course of a magistracy first semester, helps to understand these above-mentioned processes. The general questions of human physiology being besides, all the students are gotten acquainted with ecological and production factors on a human body adverse impacts consequences and with the methods of its analysis, prevention and health risks studies. The most part of a course is presented with the practical trainings permitting the students to gain the basic skills of an organism functional condition main systems for analysis. The innovative “bronkhofonografiya” technique (with the CDC applications “Pattern-1” EE and LS chairs developed) is used for the respiratory organs conditions analysis along with the traditional spirometry methods.

  17. Atmospheric Ionizing Radiation (AIR): Analysis, Results, and Lessons Learned From the June 1997 ER-2 Campaign

    Science.gov (United States)

    Wilson, J. W. (Editor); Jones, I. W. (Editor); Maiden, D. L. (Editor); Goldhagen, P. (Editor)

    2003-01-01

    The United States initiated a program to assess the technology required for an environmentally safe and operationally efficient High Speed Civil Transport (HSCT) for entrance on the world market after the turn of the century. Due to the changing regulations on radiation exposures and the growing concerns over uncertainty in our knowledge of atmospheric radiations, the NASA High Speed Research Project Office (HSRPO) commissioned a review of "Radiation Exposure and High-Altitude Flight" by the National Council on Radiation Protection and Measurements (NCRP). On the basis of the NCRP recommendations, the HSRPO funded a flight experiment to resolve the environmental uncertainty in the atmospheric ionizing radiation levels as a step in developing an approach to minimize the radiation impact on HSCT operations. To minimize costs in this project, an international investigator approach was taken to assure coverage with instrument sensitivity across the range of particle types and energies to allow unique characterization of the diverse radiation components. The present workshop is a result of the flight measurements made at the maximum intensity of the solar cycle modulated background radiation levels during the month of June 1997.

  18. Atmospheric neutrino oscillation analysis with external constraints in Super-Kamiokande I-IV

    Science.gov (United States)

    Abe, K.; Bronner, C.; Haga, Y.; Hayato, Y.; Ikeda, M.; Iyogi, K.; Kameda, J.; Kato, Y.; Kishimoto, Y.; Marti, Ll.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakajima, T.; Nakano, Y.; Nakayama, S.; Okajima, Y.; Orii, A.; Pronost, G.; Sekiya, H.; Shiozawa, M.; Sonoda, Y.; Takeda, A.; Takenaka, A.; Tanaka, H.; Tasaka, S.; Tomura, T.; Akutsu, R.; Irvine, T.; Kajita, T.; Kametani, I.; Kaneyuki, K.; Nishimura, Y.; Okumura, K.; Richard, E.; Tsui, K. M.; Labarga, L.; Fernandez, P.; Blaszczyk, F. d. M.; Gustafson, J.; Kachulis, C.; Kearns, E.; Raaf, J. L.; Stone, J. L.; Sulak, L. R.; Berkman, S.; Tobayama, S.; Goldhaber, M.; Carminati, G.; Elnimr, M.; Kropp, W. R.; Mine, S.; Locke, S.; Renshaw, A.; Smy, M. B.; Sobel, H. W.; Takhistov, V.; Weatherly, P.; Ganezer, K. S.; Hartfiel, B. L.; Hill, J.; Hong, N.; Kim, J. Y.; Lim, I. T.; Park, R. G.; Akiri, T.; Himmel, A.; Li, Z.; O'Sullivan, E.; Scholberg, K.; Walter, C. W.; Wongjirad, T.; Ishizuka, T.; Nakamura, T.; Jang, J. S.; Choi, K.; Learned, J. G.; Matsuno, S.; Smith, S. N.; Amey, J.; Litchfield, R. P.; Ma, W. Y.; Uchida, Y.; Wascko, M. O.; Cao, S.; Friend, M.; Hasegawa, T.; Ishida, T.; Ishii, T.; Kobayashi, T.; Nakadaira, T.; Nakamura, K.; Oyama, Y.; Sakashita, K.; Sekiguchi, T.; Tsukamoto, T.; Abe, KE.; Hasegawa, M.; Suzuki, A. T.; Takeuchi, Y.; Yano, T.; Hayashino, T.; Hirota, S.; Huang, K.; Ieki, K.; Jiang, M.; Kikawa, T.; Nakamura, KE.; Nakaya, T.; Patel, N. D.; Suzuki, K.; Takahashi, S.; Wendell, R. A.; Anthony, L. H. V.; McCauley, N.; Pritchard, A.; Fukuda, Y.; Itow, Y.; Mitsuka, G.; Murase, M.; Muto, F.; Suzuki, T.; Mijakowski, P.; Frankiewicz, K.; Hignight, J.; Imber, J.; Jung, C. K.; Li, X.; Palomino, J. L.; Santucci, G.; Vilela, C.; Wilking, M. J.; Yanagisawa, C.; Ito, S.; Fukuda, D.; Ishino, H.; Kayano, T.; Kibayashi, A.; Koshio, Y.; Mori, T.; Nagata, H.; Sakuda, M.; Xu, C.; Kuno, Y.; Wark, D.; Di Lodovico, F.; Richards, B.; Tacik, R.; Kim, S. B.; Cole, A.; Thompson, L.; Okazawa, H.; Choi, Y.; Ito, K.; Nishijima, K.; Koshiba, M.; Totsuka, Y.; Suda, Y.; Yokoyama, M.; Calland, R. G.; Hartz, M.; Martens, K.; Quilain, B.; Simpson, C.; Suzuki, Y.; Vagins, M. R.; Hamabe, D.; Kuze, M.; Yoshida, T.; Ishitsuka, M.; Martin, J. F.; Nantais, C. M.; de Perio, P.; Tanaka, H. A.; Konaka, A.; Chen, S.; Wan, L.; Zhang, Y.; Wilkes, R. J.; Minamino, A.; Super-Kamiokande Collaboration

    2018-04-01

    An analysis of atmospheric neutrino data from all four run periods of Super-Kamiokande optimized for sensitivity to the neutrino mass hierarchy is presented. Confidence intervals for Δ m322 , sin2θ23, sin2θ13 and δC P are presented for normal neutrino mass hierarchy and inverted neutrino mass hierarchy hypotheses, based on atmospheric neutrino data alone. Additional constraints from reactor data on θ13 and from published binned T2K data on muon neutrino disappearance and electron neutrino appearance are added to the atmospheric neutrino fit to give enhanced constraints on the above parameters. Over the range of parameters allowed at 90% confidence level, the normal mass hierarchy is favored by between 91.9% and 94.5% based on the combined Super-Kamiokande plus T2K result.

  19. Neutron activation analysis of the atmosphere content in the Central Asia south regions

    International Nuclear Information System (INIS)

    Niyazova, O.A.; Turaev, Eh.Yu.

    2001-01-01

    By the method of neutron activation analysis a atmospheric air elementary content of south regions of Uzbekistan and Turkmenistan during the 'Afghan' dust-storm were studied. Comparison with data for atmospheric air before nad after this phenomenon was carried out.It shown, that during the 'Afghan' dust-storm the elements concentration of Au, La, Na, Sm, Hg, Cs, Zn, Co is increased in to 3-4 times. Concentration of Sc and Fe is increasing into 8-9 times. In the atmosphere with the storm beginning the Ce and Cr elements are appealing, its are absent before the 'Afghan' dust-storm. The surprise result, that Br element in air during the dust storm is disappearing

  20. Impacts of heterogeneous reactions to atmospheric peroxides: Observations and budget analysis study

    Science.gov (United States)

    Qin, Mengru; Chen, Zhongming; Shen, Hengqing; Li, Huan; Wu, Huihui; Wang, Yin

    2018-06-01

    Atmospheric peroxides play important roles in atmospheric chemistry, acting as reactive oxidants and reservoirs of HOX and ROX radicals. Field measurements of atmospheric peroxides were conducted over urban Beijing from 2015 to 2016, including dust storm days, haze days and different seasons. We employed a box model based on RACM2 mechanism to conduct concentration simulation and budget analysis of hydrogen peroxide (H2O2) and peroxyacetic acid (PAA). In this study, heterogeneous reaction is found to be a significant sink for atmospheric H2O2 and PAA in urban Beijing. Here, we recommend a suitable uptake coefficient formula considering the water effect for model research of peroxides. It is found that H2O2 and PAA unexpectedly maintained considerable concentrations on haze days, even higher than that on non-haze days. This phenomenon is mainly ascribed to relatively high levels of volatile organic compounds and ozone on haze days. In addition, high levels of water vapor in pollution episode can promote not only the heterogeneous uptake to aerosol phase but also the production of H2O2. Atmospheric PAA formation is suggested to be sensitive to alkenes and NOX in urban Beijing. In particular, with the help of peroxides, sulfate formation rate from heterogeneous uptake could increase by ∼4 times on haze days, indicating the potential effect of peroxides on enhancement of aerosol oxidative property and secondary sulfate formation.

  1. Atmospheric deposition of nutrients to north Florida rivers: A multivariate statistical analysis. Final report. Master's thesis

    International Nuclear Information System (INIS)

    Fu, J.

    1991-01-01

    Atmospheric nutrient input to the Apalachicola Bay estuary was studied because it has been demonstrated that atmospheric deposition can be a major source of nutrients to eastern U.S. estuaries. Besides the Apalachicola River, the Sopchoppy and the Ochlockonee were also selected for a comparative analysis. Receptor model, absolute principal of component analysis (APCA), and mass balance methods were applied in the study. The results of the study show that nitrogen is probably not a limiting nutrient in the three rivers because their N:P mole ratios are nearly 3 times higher than the Redfield ratio for photosynthesis. The total atmospheric nitrogen depositions in the three river watershed are at least as great as their river fluxes. In the Apalachicola River, the atmospheric source of nitrogen is found to be several times higher than the largest possible input of urban sewage. Atmospheric deposition, therefore, might be the dominant nitrogen source entering the estuary. The results of APCA show that Apalachicola River water is mainly a mixture of components that correspond in their compositions to aged rain, ground water, and fresh rain. Atmospheric nitrate deposition is the result of the air pollution, i.e., acid rain. The studies also show that the annual average deposition of nitrate has a narrow range, mainly from 5.8 to 11.5 kg/ha/yr in most of the NADP sites in the 8 southeastern states. Since all the software and data sets employed in the study are accessible nationwide, the methods could be applied in other watersheds

  2. Analysis of wave-like oscillations in parameters of sporadic E layer and neutral atmosphere

    Science.gov (United States)

    Mošna, Z.; Koucká Knížová, P.

    2012-12-01

    The present study mainly concerns the wave-like activity in the ionospheric sporadic E layer (Es) and in the lower lying stratosphere. The proposed analysis involves parameters describing the state of plasma in the sporadic E layer. Critical frequencies foEs and layer heights hEs were measured at the Pruhonice station (50°N, 14.5°E) during summer campaigns 2004, 2006 and 2008. Further, we use neutral atmosphere (temperature data at 10 hPa) data from the same time interval. The analysis concentrates on vertically propagating wave-like structures within distant atmospheric regions. By means of continuous wavelet transform (CWT) we have detected significant wave-like oscillation at periods covering tidal and planetary oscillation domains both in the Es layer parameters (some of them were reported earlier, for instance in works of Abdu et al., 2003; Pancheva and Mitchel, 2004; Pancheva et al., 2003; Šauli and Bourdillon, 2008) and in stratospheric temperature variations. Further analyses using cross wavelet transform (XWT) and wavelet coherence analysis (WTC) show that despite high wave-like activity in a wide period range, there are only limited coherent wave-like bursts present in both spectra. Such common coherent wave bursts occur on periods close to eigen-periods of the terrestrial atmosphere. We suppose that vertical coupling between atmospheric regions realized by vertically propagating planetary waves occurs predominantly on periods close to those of Rossby modes. Analysis of the phase shift between data from distant atmospheric regions reveals high variability and very likely supports the non-linear scenario of the vertical coupling provided by planetary waves.

  3. Evaluation of submarine atmospheres: effects of carbon monoxide, carbon dioxide and oxygen on general toxicology, neurobehavioral performance, reproduction and development in rats. I. Subacute exposures.

    Science.gov (United States)

    Hardt, Daniel J; James, R Arden; Gut, Chester P; McInturf, Shawn M; Sweeney, Lisa M; Erickson, Richard P; Gargas, Michael L

    2015-02-01

    The inhalation toxicity of submarine contaminants is of concern to ensure the health of men and women aboard submarines during operational deployments. Due to a lack of adequate prior studies, potential general, neurobehavioral, reproductive and developmental toxicity was evaluated in male and female rats exposed to mixtures of three critical submarine atmospheric components: carbon monoxide (CO) and carbon dioxide (CO2; levels elevated above ambient), and oxygen (O2; levels decreased below ambient). In a 14-day, 23 h/day, whole-body inhalation study of exposure to clean air (0.4 ppm CO, 0.1% CO2 and 20.6% O2), low-dose, mid-dose and high-dose gas mixtures (high dose of 88.4 ppm CO, 2.5% CO2 and 15.0% O2), no adverse effects on survival, body weight or histopathology were observed. Reproductive, developmental and neurobehavioral performance were evaluated after a 28-day exposure in similar atmospheres. No adverse effects on estrus phase, mating, gestation or parturition were observed. No developmental or functional deficits were observed in either exposed parents or offspring related to motor activity, exploratory behavior or higher-level cognitive functions (learning and memory). Only minimal effects were discovered in parent-offspring emotionality tests. While statistically significant increases in hematological parameters were observed in the offspring of exposed parents compared to controls, these parameters remained within normal clinical ranges for blood cells and components and were not considered adverse. In summary, subacute exposures to elevated concentrations of the submarine atmosphere gases did not affect the ability of rats to reproduce and did not appear to have any significant adverse health effects.

  4. Critical Evaluation of Air-Liquid Interface Cell Exposure Systems for in Vitro Assessment of Atmospheric Pollutants

    Science.gov (United States)

    We compared various in vitro exposure systems for their ability to expose cells to particles and gases. The systems tested use different mechanisms to deliver multi-pollutants to the cells: diffusion, sedimentation, thermophoresis (THP) and electrostatic precipitation (ESP). Vari...

  5. New analysis indicates no thermal inversion in the atmosphere of HD 209458b

    International Nuclear Information System (INIS)

    Diamond-Lowe, Hannah; Stevenson, Kevin B.; Bean, Jacob L.; Line, Michael R.; Fortney, Jonathan J.

    2014-01-01

    An important focus of exoplanet research is the determination of the atmospheric temperature structure of strongly irradiated gas giant planets, or hot Jupiters. HD 209458b is the prototypical exoplanet for atmospheric thermal inversions, but this assertion does not take into account recently obtained data or newer data reduction techniques. We reexamine this claim by investigating all publicly available Spitzer Space Telescope secondary-eclipse photometric data of HD 209458b and performing a self-consistent analysis. We employ data reduction techniques that minimize stellar centroid variations, apply sophisticated models to known Spitzer systematics, and account for time-correlated noise in the data. We derive new secondary-eclipse depths of 0.119% ± 0.007%, 0.123% ± 0.006%, 0.134% ± 0.035%, and 0.215% ± 0.008% in the 3.6, 4.5, 5.8, and 8.0 μm bandpasses, respectively. We feed these results into a Bayesian atmospheric retrieval analysis and determine that it is unnecessary to invoke a thermal inversion to explain our secondary-eclipse depths. The data are well fitted by a temperature model that decreases monotonically between pressure levels of 1 and 0.01 bars. We conclude that there is no evidence for a thermal inversion in the atmosphere of HD 209458b.

  6. Exposure to polycyclic aromatic hydrocarbons in atmospheric PM1.0 of urban environments: Carcinogenic and mutagenic respiratory health risk by age groups.

    Science.gov (United States)

    Agudelo-Castañeda, Dayana M; Teixeira, Elba C; Schneider, Ismael L; Lara, Sheila Rincón; Silva, Luis F O

    2017-05-01

    We investigated the carcinogenic and mutagenic respiratory health risks related to the exposure to atmospheric PAHs in an urban area. Our study focused in the association of these pollutants and their possible effect in human health, principally respiratory and circulatory diseases. Also, we determined a relationship between the inhalation risk of PAHs and meteorological conditions. We validated the hypothesis that in winter PAHs with high molecular weight associated to submicron particles (PM 1 ) may increase exposure risk, especially for respiratory diseases, bronchitis and pneumonia diseases. Moreover, in our study we verified the relationship between diseases and several carcinogenic PAHs (Ind, BbkF, DahA, BaP, and BghiP). These individual PAHs contributed the most to the potential risk of exposure for inhalation of PM 1.0 . Even at lower ambient concentrations of BaP and DahA in comparison with individual concentrations of other PAHs associated to PM 1.0 . Mainly, research suggests to include carcinogenic and mutagenic PAHs in future studies of environmental health risk due to their capacity to associate to PM 10 . Such carcinogenic and mutagenic PAHs are likely to provide the majority of the human exposure, since they originate from dense traffic urban areas were humans congregate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Radiation exposure usage accountability and impact with respect to ALAP (ALARA) analysis

    International Nuclear Information System (INIS)

    Williams, M.C.

    1978-01-01

    A unique method has been developed for radiation exposure usage accounting at the N Reactor. This method accounts for exposure usage by specific job and working crafts. The accounting system provides information for use in job planning, exposure resource management, and ALAP (ALARA) analysis. It provides justification for ALAP expenditures, documentation of the effectiveness of exposure reduction efforts, and can be used to establish priorities for ALAP efforts

  8. An Analysis of Cassini Observations Regarding the Structure of Jupiter's Equatorial Atmosphere

    Science.gov (United States)

    Choi, David S.; Simon-Miller, Amy A.

    2012-01-01

    A variety of intriguing atmospheric phenomena reside on both sides of Jupiter's equator. 5-micron bright hot spots and opaque plumes prominently exhibit dynamic behavior to the north, whereas compact, dark chevron-shaped features and isolated anticyclonic disturbances periodically occupy the southern equatorial latitudes. All of these phenomena are associated with the vertical and meridional perturbations of Rossby waves disturbing the mean atmospheric state. As previous observational analysis and numerical simulations have investigated the dynamics of the region, an examination of the atmosphere's vertical structure though radiative transfer analysis is necessary for improved understanding of this unique environment. Here we present preliminary analysis of a multispectral Cassini imaging data set acquired during the spacecraft's flyby of Jupiter in 2000. We evaluated multiple methane and continuum spectral channels at available viewing angles to improve constraints on the vertical structure of the haze and cloud layers comprising these interesting features. Our preliminary results indicate distinct differences in the structure for both hemispheres. Upper troposphere hazes and cloud layers are prevalent in the northern equatorial latitudes, but are not present in corresponding southern latitudes. Continued analysis will further constrain the precise structure present in these phenomena and the differences between them.

  9. Mental retardation after prenatal exposure. Re-analysis indicated

    International Nuclear Information System (INIS)

    Paile, W.

    2000-01-01

    The current risk assessment for severe mental retardation after prenatal exposure to the A-bomb radiation is based on 21 cases exposed to more than 0.005 Gy, of which 17 were exposed in the most sensitive period 8-15 weeks p.c. The latest analysis, applying the best fitting model, indicates a threshold with a lower 95% bound of 0.06-0.31 Gy, depending on whether 2 cases with Down's syndrome are included or not. The authors have interpreted this as suggesting a threshold in the low-dose region. In the dose group 0.10-0.49 Gy, except one case with Down's syndrome there is only one other case, exposed 8 weeks p.c. to 0.14 Gy. However, in a RERF report (TR 13-91) concerning brain abnormalities detected by MRI in retarded persons, the same case is described. According to this report he was actually exposed to 0.86 Gy. The distance was 1060 m, and his mother exhibited severe epilation. These details indicate that the higher dose is correct and the lower dose is erroneous. In a small material the misclassification of one case has a deep influence on the result of the data analysis. Reclassification of this case will lead to a considerable change in the estimated threshold, notably in the 95% lower bound of the threshold. There will be no indication of severe retardation after less than 0.5 Gy even in the most sensitive period. This does not preclude a milder effect on intelligence from lower doses. The fraction of severe retardation after exposure to 1 Sv in the period 8-15 weeks p.c. has been estimated at 40%. The effect on intelligence score has been estimated at 30 IQ units per Sv in the same period. These estimates have been combined in ICRP 60 to create a model, based on a presumed normal distribution of IQ scores, according to which the final outcome for an individual is determined by his expected IQ without exposure. Thus the dose required to make an otherwise normal individual retarded would be high, while a much lower dose would be enough to bring an individual

  10. Population exposure to ultraviolet radiation in Finland 1920-1995: Exposure trends and a time-series analysis of exposure and cutaneous melanoma incidence

    International Nuclear Information System (INIS)

    Kojo, Katja; Jansen, Christer T.; Nybom, Pia; Huurto, Laura; Laihia, Jarmo; Ilus, Taina; Auvinen, Anssi

    2006-01-01

    Ultraviolet radiation (UVR) is the principal cause of cutaneous malignant melanoma (CMM). However, the relation between CMM and UVR exposure is not clear. We present the trends of population exposure to UVR and conduct a time-series analysis of the relation between UVR exposure and incidence of CMM. Data on CMM incidence were obtained from the Finnish Cancer Registry. Clothing coverage of the body was scored from archival photographs and the proportion of uncovered skin was used as a measure of solar exposure. Information on the number of sunny resort holidays, duration of annual holidays, and sunscreen sales were obtained from various sources. Exposed skin area doubled from 1920 to 1985. The average duration of annual holidays increased 30-fold. The number of sunny resort holidays and the sales of sunscreens increased rapidly from 1980. CMM was most strongly associated with solar exposure of 5-19 years earlier. There is a considerable decrease in clothing coverage during the 20th century. UVR exposure preceding CMM occurrence 4 years or less does not appear relevant, whereas the period 5-19 years prior to CMM occurrence might be the most relevant period. However, findings of ecological studies may not be applicable at the individual level

  11. Desorption atmospheric pressure photoionization high-resolution mass spectrometry: a complementary approach for the chemical analysis of atmospheric aerosols

    Czech Academy of Sciences Publication Activity Database

    Parshintsev, J.; Vaikkinen, A.; Lipponen, K.; Vrkoslav, Vladimír; Cvačka, Josef; Kostiainen, R.; Kotiaho, T.; Hartonen, K.; Riekkola, M. L.; Kauppila, T. J.

    2015-01-01

    Roč. 29, č. 13 (2015), s. 1233-1241 ISSN 0951-4198 Grant - others:GA AV ČR(CZ) M200551204 Institutional support: RVO:61388963 Keywords : atmospheric aerosols * mass spectrometry * ambient ionization Subject RIV: CB - Analytical Chemistry , Separation Impact factor: 2.226, year: 2015

  12. Super-atmospheric pressure ionization mass spectrometry and its application to ultrafast online protein digestion analysis.

    Science.gov (United States)

    Chen, Lee Chuin; Ninomiya, Satoshi; Hiraoka, Kenzo

    2016-06-01

    Ion source pressure plays a significant role in the process of ionization and the subsequent ion transmission inside a mass spectrometer. Pressurizing the ion source to a gas pressure greater than atmospheric pressure is a relatively new approach that aims to further improve the performance of atmospheric pressure ionization sources. For example, under a super-atmospheric pressure environment, a stable electrospray can be sustained for liquid with high surface tension such as pure water, because of the suppression of electric discharge. Even for nano-electrospray ionization (nano-ESI), which is known to work with aqueous solution, its stability and sensitivity can also be enhanced, particularly in the negative mode when the ion source is pressurized. A brief review on the development of super-atmospheric pressure ion sources, including high-pressure electrospray, field desorption and superheated ESI, and the strategies to interface these ion sources to a mass spectrometer will be given. Using a recent ESI prototype with an operating temperature at 220 °C under 27 atm, we also demonstrate that it is possible to achieve an online Asp-specific protein digestion analysis in which the whole processes of digestion, ionization and MS acquisition could be completed on the order of a few seconds. This method is fast, and the reaction can even be monitored on a near-real-time basis. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Comparison of the sensitivity of mass spectrometry atmospheric pressure ionization techniques in the analysis of porphyrinoids.

    Science.gov (United States)

    Swider, Paweł; Lewtak, Jan P; Gryko, Daniel T; Danikiewicz, Witold

    2013-10-01

    The porphyrinoids chemistry is greatly dependent on the data obtained in mass spectrometry. For this reason, it is essential to determine the range of applicability of mass spectrometry ionization methods. In this study, the sensitivity of three different atmospheric pressure ionization techniques, electrospray ionization, atmospheric pressure chemical ionization and atmospheric pressure photoionization, was tested for several porphyrinods and their metallocomplexes. Electrospray ionization method was shown to be the best ionization technique because of its high sensitivity for derivatives of cyanocobalamin, free-base corroles and porphyrins. In the case of metallocorroles and metalloporphyrins, atmospheric pressure photoionization with dopant proved to be the most sensitive ionization method. It was also shown that for relatively acidic compounds, particularly for corroles, the negative ion mode provides better sensitivity than the positive ion mode. The results supply a lot of relevant information on the methodology of porphyrinoids analysis carried out by mass spectrometry. The information can be useful in designing future MS or liquid chromatography-MS experiments. Copyright © 2013 John Wiley & Sons, Ltd.

  14. Exploratory analysis of atmospheric pollution in a coastal forest ecosystem in central Italy

    Directory of Open Access Journals (Sweden)

    Rita Aromolo

    2015-02-01

    Full Text Available Exploratory analysis of atmospheric pollution in a coastal forest ecosystem in central Italy - The study of spatial and temporal distribution of heavy metals in the atmosphere through the continuous assessment of deposition is of great interest for the analysis of anthropogenic pressure on the environment and the potential toxicity to humans and other living organisms. Information based on reliable estimates of heavy metals is therefore crucial for the evaluation of environmental quality. Trends in heavy metal concentration in atmospheric depositions on a coastal forest ecosystem (Castelporziano, Rome are analyzed in the present study based on a three-year monitoring field survey over three sites representative of different woodland characteristics in the area. Our results highlight both the influence of transportation processes in the short and medium distance based on the human pressure reflecting urban expansion and infrastructure development on the fringe of Castelporziano pristine forest. Further studies investigating the latent correlation with meteorological variables at various temporal scales are needed to provide a comprehensive picture of environmental conditions in a forest ecosystem subjected to increasing human pressure. Analysis of runoff water quality and the determination of other heavy metals, such as arsenic, may identify additional sources of pollution impacting soil and forest ecosystem.

  15. Critical Evaluation of Air-Liquid Interface Cell Exposure Systems for In Vitro Assessment of Atmospheric Pollutants##

    Science.gov (United States)

    Conventional in vitro exposure studies of airborne pollutants involve, for example, the addition of particulate matter (PM) or PM extracts to the cell culture medium, or the bubbling of gases into the culture medium; these methods alter the pollutant’s physical and chemical...

  16. Prenatal exposure to polychlorinated biphenyls: a neuropsychologic analysis.

    Science.gov (United States)

    Boucher, Olivier; Muckle, Gina; Bastien, Célyne H

    2009-01-01

    A large body of literature documents the effects of prenatal exposure to polychlorinated biphenyls (PCBs) on cognitive development of children. Despite this fact, no integrative synthesis has been published yet to identify the cognitive functions that are particularly affected. Our aim is to review this literature in an attempt to identify the cognitive profile associated with prenatal PCB exposure. Studies were identified by searching the PubMed database for articles published before June 2008. We reviewed data from nine prospective longitudinal birth cohorts for different aspects of cognition. Associations between indicators of prenatal PCB exposure and performance on cognitive tasks reported in the selected studies are summarized and classified as general cognitive abilities, verbal or visual-spatial skills, memory, attention, and executive functions. The most consistent effects observed across studies are impaired executive functioning related to increased prenatal PCB exposure. Negative effects on processing speed, verbal abilities, and visual recognition memory are also reported by most studies. Converging results from different cohort studies in which exposure arises from different sources make it unlikely that co-exposure with another associated contaminant is responsible for the observed effects. Prenatal PCB exposure appears to be related to a relatively specific cognitive profile of impairments. Failure to assess functions that are specifically impaired may explain the absence of effects found in some studies. Our findings have implications in the selection of cognitive assessment methods in future studies.

  17. Quantitative plasma biomarker analysis in HDI exposure assessment.

    Science.gov (United States)

    Flack, Sheila L; Fent, Kenneth W; Trelles Gaines, Linda G; Thomasen, Jennifer M; Whittaker, Steve; Ball, Louise M; Nylander-French, Leena A

    2010-01-01

    Quantification of amines in biological samples is important for evaluating occupational exposure to diisocyanates. In this study, we describe the quantification of 1,6-hexamethylene diamine (HDA) levels in hydrolyzed plasma of 46 spray painters applying 1,6-hexamethylene diisocyanate (HDI)-containing paint in vehicle repair shops collected during repeated visits to their workplace and their relationship with dermal and inhalation exposure to HDI monomer. HDA was detected in 76% of plasma samples, as heptafluorobutyryl derivatives, and the range of HDA concentrations was HDA levels and HDI inhalation exposure measured on the same workday was low (N = 108, r = 0.22, P = 0.026) compared with the correlation between plasma HDA levels and inhalation exposure occurring approximately 20 to 60 days before blood collection (N = 29, r = 0.57, P = 0.0014). The correlation between plasma HDA levels and HDI dermal exposure measured on the same workday, although statistically significant, was low (N = 108, r = 0.22, P = 0.040) while the correlation between HDA and dermal exposure occurring approximately 20 to 60 days before blood collection was slightly improved (N = 29, r = 0.36, P = 0.053). We evaluated various workplace factors and controls (i.e. location, personal protective equipment use and paint booth type) as modifiers of plasma HDA levels. Workers using a downdraft-ventilated booth had significantly lower plasma HDA levels relative to semi-downdraft and crossdraft booth types (P = 0.0108); this trend was comparable to HDI inhalation and dermal exposure levels stratified by booth type. These findings indicate that HDA concentration in hydrolyzed plasma may be used as a biomarker of cumulative inhalation and dermal exposure to HDI and for investigating the effectiveness of exposure controls in the workplace.

  18. Analysis of the outlook for using narrow-band spontaneous emission sources for atmospheric air purification

    International Nuclear Information System (INIS)

    Boyarchuk, K A; Karelin, A V; Shirokov, R V

    2003-01-01

    The outlook for using narrow-band spontaneous emission sources for purification of smoke gases from sulphur and nitrogen oxides is demonstrated by calculations based on a nonstationary kinetic model of the N 2 - O 2 - H 2 O - CO 2 - SO 2 mixture. The dependences of the mixture purification efficiency on the UV source power at different wavelengths, the exposure time, and the mixture temperature are calculated. It is shown that the radiation sources proposed in the paper will provide better purification of waste gases in the atmosphere. The most promising is a KrCl* lamp emitting an average power of no less than 100 W at 222 nm. (laser applications and other topics in quantum electronics)

  19. NTP Toxicity Study Report on the atmospheric characterization, particle size, chemical composition, and workplace exposure assessment of cellulose insulation (CELLULOSEINS).

    Science.gov (United States)

    Morgan, Daniel L

    2006-08-01

    Cellulose insulation (CI) is a type of thermal insulation produced primarily from recycled newspapers. The newspapers are shredded, milled, and treated with fire-retardant chemicals. The blowing process for installing CI generates a significant quantity of airborne material that presents a potential inhalation hazard to workers. CI was selected for study based upon the high production volume, the potential for widespread human exposure, and a lack of toxicity data; insufficient information was available to determine whether inhalation studies in laboratory animals were technically feasible or necessary. Studies were conducted to characterize the chemical and physical properties of CI aerosols, to evaluate the potential acute pulmonary toxicity of CI, and to assess occupational exposure of CI installers. Workplace exposure assessments were conducted in collaboration with the National Institute for Occupational Safety and Health (NIOSH, 2001). Chemical analyses were performed on samples of bulk CI from four major United States manufacturers. All samples of the bulk CI were found to contain primarily amorphous cellulose (60% to 65%) with a smaller crystalline component (35% to 40%). The crystalline phase was primarily native cellulose (75% to 85%) with a minor amount of cellulose nitrate (15% to 25%). Elemental analyses of acid digests of CI materials indicated that the major components (>0.1% by weight) included aluminum, boron, calcium, sodium, and sulfur. An acid-insoluble residue present in all four materials (3% to 5% of original sample weight) was found to consist primarily of aluminum silicate hydroxide (kaolinite; approximately 85%) with minor amounts (application and that the acute pulmonary toxicity is minimal. The CI exposure assessment was conducted with 10 contractors located across the United States. Air samples of total dust and respirable dust were collected for scanning electron microscopy (SEM) to characterize any fibers in the dust. Two SEM air

  20. Association rule mining data for census tract chemical exposure analysis

    Data.gov (United States)

    U.S. Environmental Protection Agency — Chemical concentration, exposure, and health risk data for U.S. census tracts from National Scale Air Toxics Assessment (NATA). This dataset is associated with the...

  1. Interpreting faecal analysis results for monitoring exposure to uranium

    International Nuclear Information System (INIS)

    Berard, P.; Rongier, E.; Faure, M.L.; Auriol, B.; Estrabaud, M.; Mazeyrat, C.

    1996-01-01

    Radiotoxicological monitoring of workers exposed to non-transferable forms of uranium requires six-monthly examinations. These examinations are prescribed according to the kind of product manipulated and tO the industrial risk attached to the workplace. The range of examinations that are useful for this kind of monitoring includes whole body counting examinations, urine analyses and in-line faecal sampling: whole body examinations, which are fundamental to monitoring, provide a lung retention value. However, the detection limit of lung examinations is not low enough for chronic operational monitoring; urine examinations are extremely sensitive to alpha activity (1 mBq per isotope) but the fraction detected in the urine after incorporation by inhalation is very small; in-line 24-hour faecal sampling allows avoiding any workplace exclusion. The authors intend to present their experience acquired over a six year period in the field of systematic faecal examinations after chronic inhalation of the different uranium compounds. They also present results of a study carried out to determine normal uranium concentrations in the faeces of a non-exposed population, the uranium content in drinking waters and the consequences on faecal excretion. Establishing the isotopic content of uranium in the faeces makes it possible to determine practical investigation levels for occupational monitoring. Even if faecal sampling may be critically perceived by the personnel, the authors' experience highlights the value of this kind of analysis which allows to track down the industrial reality of the exposure. Internal dosimetry calculations cannot, however, be carried out, because the physical parameters of the inhaled aerosols are not always known. (author)

  2. Study plan for the sensitivity analysis of the Terrain-Responsive Atmospheric Code (TRAC)

    International Nuclear Information System (INIS)

    Restrepo, L.F.; Deitesfeld, C.A.

    1987-01-01

    Rocky Flats Plant, Golden, Colorado is presently developing a computer code to model the dispersion of potential or actual releases of radioactive or toxic materials to the environment, along with the public consequences from these releases. The model, the Terrain-Responsive Atmospheric Code (TRAC), considers several complex features which could affect the overall dispersion and consequences. To help validate TRAC, a sensitivity analysis is being planned to determine how sensitive the model's solutions are to input variables. This report contains a brief description of the code, along with a list of tasks and resources needed to complete the sensitivity analysis

  3. Occupational Exposure to HDI: Progress and Challenges in Biomarker Analysis

    OpenAIRE

    Flack, Sheila L.; Ball, Louise M.; Nylander-French, Leena A.

    2010-01-01

    1,6-hexamethylene diisocyanate (HDI) is extensively used in the automotive repair industry and is a commonly reported cause of occupational asthma in industrialized populations. However, the exact pathological mechanism remains uncertain. Characterization and quantification of biomarkers resulting from HDI exposure can fill important knowledge gaps between exposure, susceptibility, and the rise of immunological reactions and sensitization leading to asthma. Here, we discuss existing challenge...

  4. The analysis of radiation exposure of hospital radiation workers

    International Nuclear Information System (INIS)

    Jeong, Tae Sik; Shin, Byung Chul; Moon, Chang Woo; Cho, Yeong Duk; Lee, Yong Hwan; Yum, Ha Yong

    2000-01-01

    This investigation was performed in order to improve the health care of radiation workers, to predict a risk, to minimize the radiation exposure hazard to them and for them to realize radiation exposure danger when they work in radiation area in hospital. The documentations checked regularly for personal radiation exposure in four university hospitals in Pusan city in Korea between January 1, 1993 and December 31, 1997 were analyz ed. There were 458 persons in this documented but 111 persons who worked less then one year were excluded and only 347 persons were included in this study. The average of yearly radiation exposure of 347 persons was 1.52±1.35 mSv. Though it was less than 5OmSv, the limitaion of radiation in law but 125 (36%) people received higher radiation exposure than non-radiation workers. Radiation workers under 30 year old have received radiation exposure of mean 1.87±1.01 mSv/year, mean 1.22±0.69 mSv between 31 and 40 year old and mean 0.97±0.43 mSv/year over, 41year old (p<0.001). Men received mean 1.67±1.54 mSv/year were higher than women who received mean 1.13±0.61 mSv/year (p<0.01). Radiation exposure in the department of nuclear medicine department in spite of low energy sources is higher than other departments that use radiations in hospital (p<0.05). And the workers who received mean 3.69±1.81 mSv/year in parts of management of radiation sources and injection of sources to patient receive high radiation exposure in nuclear medicine department (0<0.01). In department of diagnostic radiology high radiation exposure is in barium enema rooms where workers received mean 3.74±1.74 mSv/year and other parts where they all use fluoroscopy such as angiography room of mean 1.17±0.35 mSv/year and upper gastrointestinal room of mean 1.74±1.34 mSv/year represented higher radiation exposure than average radiation exposure in diagnostic radiology (p<0.01). Doctors and radiation technologists received higher radiation exposure of each mean 1.75±1

  5. The effects of atmospheric pollutants upon standstone: evidence from real time measurements and analysis of decay features on historic buildings

    Energy Technology Data Exchange (ETDEWEB)

    Halsey, D.P.; Dews, J.; Harris, F.C. [Wolverhampton Univ. (United Kingdom). School of Construction, Engineering and Technology; Mitchell, D.J. [Wolverhampton Univ. (United Kingdom). School of Applied Sciences

    1995-12-31

    Due to the urbanisation and industrialisation of the West Midlands, UK, historic sandstone buildings are exposed to atmospheric pollution. In order to assess the impact of this pollution upon their deterioration, chemical analysis of runoff water, from sandstone and control surfaces, has been carried out. The amount of stone affected by atmospheric pollution has been quantified by surveying selected sandstone buildings. (author)

  6. The effects of atmospheric pollutants upon standstone: evidence from real time measurements and analysis of decay features on historic buildings

    Energy Technology Data Exchange (ETDEWEB)

    Halsey, D P; Dews, J; Harris, F C [Wolverhampton Univ. (United Kingdom). School of Construction, Engineering and Technology; Mitchell, D J [Wolverhampton Univ. (United Kingdom). School of Applied Sciences

    1996-12-31

    Due to the urbanisation and industrialisation of the West Midlands, UK, historic sandstone buildings are exposed to atmospheric pollution. In order to assess the impact of this pollution upon their deterioration, chemical analysis of runoff water, from sandstone and control surfaces, has been carried out. The amount of stone affected by atmospheric pollution has been quantified by surveying selected sandstone buildings. (author)

  7. Precipitation recycling in West Africa - regional modeling, evaporation tagging and atmospheric water budget analysis

    Science.gov (United States)

    Arnault, Joel; Kunstmann, Harald; Knoche, Hans-Richard

    2015-04-01

    Many numerical studies have shown that the West African monsoon is highly sensitive to the state of the land surface. It is however questionable to which extend a local change of land surface properties would affect the local climate, especially with respect to precipitation. This issue is traditionally addressed with the concept of precipitation recycling, defined as the contribution of local surface evaporation to local precipitation. For this study the West African monsoon has been simulated with the Weather Research and Forecasting (WRF) model using explicit convection, for the domain (1°S-21°N, 18°W-14°E) at a spatial resolution of 10 km, for the period January-October 2013, and using ERA-Interim reanalyses as driving data. This WRF configuration has been selected for its ability to simulate monthly precipitation amounts and daily histograms close to TRMM (Tropical Rainfall Measuring Mission) data. In order to investigate precipitation recycling in this WRF simulation, surface evaporation tagging has been implemented in the WRF source code as well as the budget of total and tagged atmospheric water. Surface evaporation tagging consists in duplicating all water species and the respective prognostic equations in the source code. Then, tagged water species are set to zero at the lateral boundaries of the simulated domain (no inflow of tagged water vapor), and tagged surface evaporation is considered only in a specified region. All the source terms of the prognostic equations of total and tagged water species are finally saved in the outputs for the budget analysis. This allows quantifying the respective contribution of total and tagged atmospheric water to atmospheric precipitation processes. The WRF simulation with surface evaporation tagging and budgets has been conducted two times, first with a 100 km2 tagged region (11-12°N, 1-2°W), and second with a 1000 km2 tagged region (7-16°N, 6°W -3°E). In this presentation we will investigate hydro-atmospheric

  8. Uncertainty evaluation in correlated quantities: application to elemental analysis of atmospheric aerosols

    International Nuclear Information System (INIS)

    Espinosa, A.; Miranda, J.; Pineda, J. C.

    2010-01-01

    One of the aspects that are frequently overlooked in the evaluation of uncertainty in experimental data is the possibility that the involved quantities are correlated among them, due to different causes. An example in the elemental analysis of atmospheric aerosols using techniques like X-ray Fluorescence (X RF) or Particle Induced X-ray Emission (PIXE). In these cases, the measured elemental concentrations are highly correlated, and then are used to obtain information about other variables, such as the contribution from emitting sources related to soil, sulfate, non-soil potassium or organic matter. This work describes, as an example, the method required to evaluate the uncertainty in variables determined from correlated quantities from a set of atmospheric aerosol samples collected in the Metropolitan Area of the Mexico Valley and analyzed with PIXE. The work is based on the recommendations of the Guide for the Evaluation of Uncertainty published by the International Organization for Standardization. (Author)

  9. Remote sensing of atmospheric water content from Bhaskara SAMIR data. [using statistical linear regression analysis

    Science.gov (United States)

    Gohil, B. S.; Hariharan, T. A.; Sharma, A. K.; Pandey, P. C.

    1982-01-01

    The 19.35 GHz and 22.235 GHz passive microwave radiometers (SAMIR) on board the Indian satellite Bhaskara have provided very useful data. From these data has been demonstrated the feasibility of deriving atmospheric and ocean surface parameters such as water vapor content, liquid water content, rainfall rate and ocean surface winds. Different approaches have been tried for deriving the atmospheric water content. The statistical and empirical methods have been used by others for the analysis of the Nimbus data. A simulation technique has been attempted for the first time for 19.35 GHz and 22.235 GHz radiometer data. The results obtained from three different methods are compared with radiosonde data. A case study of a tropical depression has been undertaken to demonstrate the capability of Bhaskara SAMIR data to show the variation of total water vapor and liquid water contents.

  10. Investigation of different types of filters for atmospheric trace elements analysis by three analytical techniques

    International Nuclear Information System (INIS)

    Ali, A.E.; Bacso, J.

    1996-01-01

    Different atmospheric aerosol samples were collected on three types of filters. Disks of both loaded and clean areas of each kind of filter were investigated by XRF, PIXE and Scanning Electron Microscope (SEM) methods. The blank concentration values of the elements Al, Si, P, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br and Pb in the three types of filters are discussed. It is found that for trace elemental analysis, the Nuclepore membrane filters are the most suitable for sampling. These have much lower blank element concentration values than the glass fibres and ash free filters. It was found also that the PIXE method is a more reliable analytical technique for atmospheric aerosol particles than the other methods. (author). 20 refs., 3 figs., 3 tabs

  11. Performance Analysis of Free-Space Optical Communication Systems With Multiuser Diversity Over Atmospheric Turbulence Channels

    KAUST Repository

    Yang, Liang

    2014-04-01

    Free-space optical (FSO) communication has become a cost-effective method to provide high data rates. However, the turbulence-induced fading limits its application to short-range applications. To address this, we propose a multiuser diversity (MD) FSO scheme in which the Nth best user is selected and the channel fluctuations can be effectively exploited to produce a selection diversity gain. More specifically, we first present the statistics analysis for the considered system over both weak and strong atmospheric turbulence channels. Based on these statistics, the outage probability, bit-error rate performance, average capacity, diversity order, and coverage are analyzed. Results show that the diversity order for the gamma-gamma fading is N min{α, β}/2, where N is the number of users, and α and β are the channel fading parameters related to the effective atmospheric conditions of the link.

  12. Analysis of Microbial Activity Under a Supercritical CO{sub 2} Atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Janelle

    2012-11-30

    Because the extent and impact of microbial activity in deep saline aquifers during geologic sequestration is unknown, the objectives of this proposal were to: (1) characterize the growth requirements and optima of a biofilm-producing supercritical CO{sub 2}-tolerant microbial consortium (labeled MIT0212) isolated from hydrocarbons recovered from the Frio Ridge, TX carbon sequestration site; (2) evaluate the ability of this consortium to grow under simulated reservoir conditions associated with supercritical CO{sub 2} injection; (3) isolate and characterize individual microbial strains from this consortium; and (4) investigate the mechanisms of supercritical CO{sub 2} tolerance in isolated strains and the consortium through genome-enabled studies. Molecular analysis of genetic diversity in the consortium MIT0212 revealed a predominance of sequences closely related to species of the spore-forming genus Bacillus. Strain MIT0214 was isolated from this consortium and characterized by physiological profiling and genomic analysis. We have shown that the strain MIT0214 is an aerobic spore-former and capable of facultative anaerobic growth under both reducing N{sub 2} and CO{sub 2} atmospheres by fermentation and possibly anaerobic respiration. Strain MIT0214 is best adapted to anaerobic growth at pressures of 1 atm but is able to growth at elevated pressures After 1 week growth was observed at pressures as high as 27 atm (N{sub 2}) or 9 atm (CO{sub 2}) and after 26-30 days growth can be observed under supercritical CO{sub 2}. In addition, we have determined that spores of strain B. cereus MIT0214 are tolerant of both direct and indirect exposure to supercritical CO{sub 2}. Additional physiological characterization under aerobic conditions have revealed MIT0214 is able to grow from temperature of 21 to 45 °C and salinities 0.01 to 40 g/L NaCl with optimal growth occurring at 30°C and from 1 - 5 g NaCl/L. The genome sequence of B. cereus MIT0214 shared 89 to 91% of genes

  13. Impact of assimilation window length on diurnal features in a Mars atmospheric analysis

    Directory of Open Access Journals (Sweden)

    Yongjing Zhao

    2015-05-01

    Full Text Available Effective simulation of diurnal variability is an important aspect of many geophysical data assimilation systems. For the Martian atmosphere, thermal tides are particularly prominent and contribute much to the Martian atmospheric circulation, dynamics and dust transport. To study the Mars diurnal variability and Mars thermal tides, the Geophysical Fluid Dynamics Laboratory Mars Global Climate Model with the 4D-local ensemble transform Kalman filter (4D-LETKF is used to perform an analysis assimilating spacecraft temperature retrievals. We find that the use of a ‘traditional’ 6-hr assimilation cycle induces spurious forcing of a resonantly enhanced semi-diurnal Kelvin waves represented in both surface pressure and mid-level temperature by forming a wave 4 pattern in the diurnal averaged analysis increment that acts as a ‘topographic’ stationary forcing. Different assimilation window lengths in the 4D-LETKF are introduced to remove the artificially induced resonance. It is found that short assimilation window lengths not only remove the spurious resonance, but also push the migrating semi-diurnal temperature variation at 50 Pa closer to the estimated ‘true’ tides even in the absence of a radiatively active water ice cloud parameterisation. In order to compare the performance of different assimilation window lengths, short-term to mid-range forecasts based on the hour 00 and 12 assimilation are evaluated and compared. Results show that during Northern Hemisphere summer, it is not the assimilation window length, but the radiatively active water ice clouds that influence the model prediction. A ‘diurnal bias correction’ that includes bias correction fields dependent on the local time is shown to effectively reduce the forecast root mean square differences between forecasts and observations, compensate for the absence of water ice cloud parameterisation and enhance Martian atmosphere prediction. The implications of these results for

  14. Exposure of unsuspecting workers to deadly atmospheres in below-ground confined spaces and investigation of related whole-air sample composition using adsorption gas chromatography.

    Science.gov (United States)

    Smith, Philip A; Lockhart, Bonnie; Besser, Brett W; Michalski, Michael A R

    2014-01-01

    Hazardous atmospheres in confined spaces may be obvious when a source of air contamination or oxygen (O2) deficiency is recognized. Such is often the case in general industry settings, especially with work processes which create hazardous atmospheres that may be anticipated. Hazards present in active sewers are also well recognized; but the possibility that O2 deficiency or high airborne contaminant concentrations may exist in new construction sewers or storm drains has been repeatedly ignored with deadly results. Low O2 and high carbon dioxide (CO2) concentrations may exist in new construction manholes that have not yet been connected to an active sewer or drain system, and these concentrations have been shown to vary over time. A recent incident is described where workers repeatedly entered such a confined space without incident, but subsequent entry resulted in a fatality and a near-miss for a co-worker rescuer. Additional cases are discussed, with an emphasis placed on elevated CO2 concentrations as a causative factor. A description is provided for the adsorptive gas chromatography whole-air analysis methodology used to quantitatively determine atmospheric conditions present at this type of fatality site or others after an incident, and for the gas chromatography-mass spectrometry method used to provide confirmation of analyte identity with high certainty. Many types of confined spaces may be encountered in addition to the underground varieties discussed, and many possible atmospheric hazards are possible. The definitive whole-air analysis approach described here may be of use and should be considered to investigate many confined space fatality and near-miss cases, and to better understand the causes of dangerous atmosphere conditions that may arise in confined spaces.

  15. Ultrastructural analysis of corneal exposure to UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pitts, D.G.; Bergmanson, J.P.G.; Chu, L.W.-F.

    1987-01-01

    The primate cornea was exposed to 300 nm UVR with five levels of radiant expsure from 0.08 to 0.6 Jcm/sup -2/. All cellular layers of the cornea were damaged at the 0.08 Jcm/sup -2/ exposure, and damage became more severe as the exposure level was increased. The corneal cells showed variable response in that essentially normal cells were found among damaged cells. Eight days post-exposure using the 0.6 Jcm/sup -2/ level, the epithelium had regained its normal thickness and was populated largely by normal appearing cells; however, the stroma showed damaged keratocytes and the loss of keratocytes. The corneal basement membranes (the epithelial basement membrane and the posterior limiting lamina) and the anterior limiting lamina were not damaged at any exposure level except for an isolated area along the epithelial basement membrane in one cornea. Therefore, one is lead to conclude that basement membranes are unaffected by UVR. The endothelium continued to demonstrate the loss of mitochondria, endoplasmic reticulum and some vacuoles at 8 days after exposure. However, the endothelium appeared to have resumed its physiological function as demonstrated by the reduced stromal oedema. This research gives the first complete description of UV-B induced corneal damage and repair of the full, in-depth cornea of the primate using the EM.

  16. Ultrastructural analysis of corneal exposure to UV radiation

    International Nuclear Information System (INIS)

    Pitts, D.G.; Bergmanson, J.P.G.; Chu, L. W-F.

    1987-01-01

    The primate cornea was exposed to 300 nm UVR with five levels of radiant expsure from 0.08 to 0.6 Jcm -2 . All cellular layers of the cornea were damaged at the 0.08 Jcm -2 exposure, and damage became more severe as the exposure level was increased. The corneal cells showed variable response in that essentially normal cells were found among damaged cells. Eight days post-exposure using the 0.6 Jcm -2 level, the epithelium had regained its normal thickness and was populated largely by normal appearing cells; however, the stroma showed damaged keratocytes and the loss of keratocytes. The corneal basement membranes (the epithelial basement membrane and the posterior limiting lamina) and the anterior limiting lamina were not damaged at any exposure level except for an isolated area along the epithelial basement membrane in one cornea. Therefore, one is lead to conclude that basement membranes are unaffected by UVR. The endothelium continued to demonstrate the loss of mitochondria, endoplasmic reticulum and some vacuoles at 8 days after exposure. However, the endothelium appeared to have resumed its physiological function as demonstrated by the reduced stromal oedema. This research gives the first complete description of UV-B induced corneal damage and repair of the full, in-depth cornea of the primate using the EM. (author)

  17. Analysis of chronic radiation exposure at small doses

    International Nuclear Information System (INIS)

    Krestinina, L.Y.

    2000-01-01

    The purpose of the study was to analyze the late effects of radiation exposure among residents of settlements located on the territory of the East-Urals Radiation Trace (EURT) in the Southern Urals. In 1957 an explosion occurred at the depot of radioactive waste in the Southern Urals. An area of 23000 km 2 was contaminated, with contamination density of over 0.1 Ci/m 2 for 90 Sr. There were 217 populated ares on that territory with total population about 270000. The residents of 22 villages with contamination density of over 4 Ci/km 2 for 90 Sr were evacuated. The times of evacuation differed from 7 to 670 days since the accident, depending on the level of contamination. In 1988-1993 an individualized registry was created at the Urals Research Center for Radiation Medicine (URCRM) which included information on the residents of 22 evacuated villages and a proportion of unevacuated residents of the EURT area. Currently, the registry contains data on 30000 residents. Of that number 17000 persons were born before, and 12000 after the accident (including about 9000 offspring of exposed residents evacuated from the EURT, and about 3000 persons who were born after the accident and have been living permanently in the EURT area). Over the 35-year period since the accident the residents have received mean effective doses ranging from 23 to 530 mSv. The mean effective doses received by permanent residents range from 5 to 60 mSv. The cohort of people exposed on the EURT territory was identified based on the information contained in the registry. If a person happened to be in the EURT area at the time of the accident, he/she was considered to be eligible for inclusion in the cohort. Over the 35-year period (from 1957 through 1992) 29.5% of 17872 residents died, and 35% of the original cohort were lost to follow-up for different reasons. To enable an analysis a control group was established which included residents of villages located outside, but close enough, to the EURT area

  18. On-site and off-site atmospheric PBDEs in an electronic dismantling workshop in south China: Gas-particle partitioning and human exposure assessment

    International Nuclear Information System (INIS)

    An Taicheng; Zhang Delin; Li Guiying; Mai Bixian; Fu Jiamo

    2011-01-01

    Gas samples and total suspended particle during work and off work time were investigated on-site and off-site electronic waste dismantling workshop (I- and O-EWDW), then compared with plastic recycling workshop (PRW) and waste incineration plant (WIP). TSP concentrations and total PBDE were 0.36-2.21 mg/m 3 and 27-2975 ng/m 3 at different workshops, respectively. BDE-47, -99, and -209 were major ΣPBDE congeners at I-EWDW and WIP, while BDE-209 was only dominant congener in PRW and control sites during work time and all sites during off work time. The gas-particle partitioning result was well correlated with the subcooled liquid vapor pressure for all samples, except for WIP and I-EDWD, at park during work time, and residential area during off work time. The predicted urban curve fitted well with measured φ values at O-DEWD during work time, whereas it was slightly overestimated or underestimated for others. Exposure assessment revealed the highest exposure site was I-EDWD. - Highlights: → On- and off-site atmospheric PBDEs was monitored in e-waste dismantling workshops in south China. → The gas-particle partitioning result was well correlated with the subcooled liquid vapor pressure for some samples. → Exposure assessment revealed that workers in I-EDWD were the highest exposure population. - The findings of this study may serve as a valuable reference for future risk assessment and environmental management in Guiyu, South China.

  19. Atmospheric effects in the entertainment industry : Constituents, exposures and health effects[Report to SHAPE the Workers' Compensation Board of BC and the BC Lung Association

    Energy Technology Data Exchange (ETDEWEB)

    Teschke, K.; Netten, C. van; Kennedy, S. [British Columbia Univ., Vancouver, BC (Canada)

    2003-03-27

    The University of British Columbia was asked by the Safety and Health in Arts Production and Entertainment to assist in investigating a number of issues concerning the safety of theatrical smokes and fogs. Specifically, the study strove to answer the following: (1) what products and equipment are used in the British Columbia (BC) entertainment industry, the chemicals that are used, and does the composition of the chemicals change once they are heated during use?, (2) what measuring equipment can be used for on-site monitoring by production staff?, (3) what levels of smokes and fogs are present in the air, the sizes of the airborne fog droplets, the type of exposure of employees?, (4) and are employees suffering ill health effects as a result of exposure? In the course of the study, 23 members of the International Alliance of Theatrical Stage Employees (IATSE) Local 891 were interviewed concerning their jobs, including the materials and equipment they use to create atmospheric effects. In addition, laboratory investigations of the constituents of the glycol fluids and their potential for pyrolysis under normal operating conditions were performed, as well as field tests of measurement methods to allow industry personnel to check exposure levels easily. The authors also performed a cross-sectional study of exposures to theatrical employees in the industry. The results showed that several technicians formulated their own fluids. Bulk samples were obtained of 15 glycol-based fluids and were found to have the same proportions of specific glycols as specified on their Material Safety Data Sheets. Three commercially available real-time direct-reading monitors were evaluated as simple monitoring methods. The preferred method was found to be the DataRAM which is easy to use, can be worn as a personal monitor and is silent. The drawback is the price (8000 dollars). Several recommendations were made. refs., tabs., figs.

  20. Influence of various parameters on the calculation of the population exposure due to discharge of radioactive matter into the atmosphere

    International Nuclear Information System (INIS)

    Schmidtlein, P.

    1980-01-01

    The evaluation of the influences of the examined parameters on the calculation of the dose rate shows that a new concept for determination of the radiation exposure in the surroundings of nuclear facilities is required. A computing formalism based on theoretical considerations determines the effective activity absorbed and, after combination with dose rate factors, the effective dose rate per year. It is of great importance to verify the validity of the still incomplete input data for determination of the dose factors of the age groups 'infants' and 'children' and to prepare new data records. (DG) [de

  1. Dose Record Analysis of External Exposure of Workers in Madagascar

    International Nuclear Information System (INIS)

    Andriambololona, R.; Ratovonjanahary, J. F.; Randriantsizafy, R. D.

    2004-01-01

    External personnel monitoring of workers in diagnostic radiology in Madagascar using thermoluminescence techniques has been studied in previous work for the period of 1990 to 2000. The study was based on the average of Hp(0.07) and Hp(10) and on the annual dose distribution. The results showed that mean doses are very low compared with the annual dose limits for workers of 20 mSv per year and are comparable with natural contribution of telluric X and gamma exposure which is evaluated as 3.21 mSv per year in Antananarivo. No trend in the average was observed, however, the last 4 years, the results showed a substantial decrease in the average from 2 mSv to 1 mSv. It was assumed that this was the impact of the implementation by radiation staff in their workplace of the in force regulation which is in compliance with the new basic safety standards. Indeed, since 1996, Madagascar-Institut National des Sciences et Techniques Nucleaires (Madagascar-INSTN) and the Association Nationale de Radioprotection de Madagascar (ANARAPMAD), the Madagascar radiation protection society and associate member of IRPA, set up a national program for training of radiation workers. The number of workers trained during this period is evaluated as 50% of the total number of radiation workers in Madagascar. The present work is a continuation of the above mentioned survey during the period of 2001 to 2003. The training program was upgraded to involve personnel who will be in charge of radiation protection and safety in workplace and the training cycle lasts 2 years instead of 3 days in the previous program. The survey has been extended to include all radiation workers in Madagascar though the medical field is still the main application and represents more than 90 percent of the latter. The results shows that for this last 3 years, an other substantial decrease from 1 mSv to 0.5 mSv was observed in the average. In the dose distribution, more than 98 percent of the Hp(0.07) and more than 99

  2. Sensitivity Analysis of Onsite Atmospheric Dispersion Factor in Westinghouse type NPP in KOREA

    International Nuclear Information System (INIS)

    Lee, Seung Chan; Yoon, Duk Joo; Song, Dong Soo

    2016-01-01

    ARCON96 is a NRC licensed air dispersion model to evaluate onsite atmospheric relative concentration X/Q. The purpose of this paper is to provide some results for checking and testing the functionalities of ARCON96. Specially, this code is optimized to estimate a habitability of control room. Since NUREG 0737 issue, the control room habitability has been studied for a FSAR (Final Safety Analysis Report). Some assumptions and methodology is used in this paper. Some methodology is introduced in this paper. The reason of the selection of 2-loop Westinghouse NPP is because of carrying out the study project for the 2-loop Westinghouse NPP in the condition of the defueled NPP condition. Onsite atmospheric dispersion factor sensitivity is performed. Key impact factor is reviewed. Some results are below: a. Time averaged effect of X/Q is timely increased. b. ARCON96 code is more conservative at the low wind speed conditions. c. Building wake impact is significant in the condition of unstable atmospheric class with more than 7m/sec of wind speed. d. Plume meander effect is strong when the distance from the release point is small. e. The other plume meander effect is strong when the meander duration time is accumulated Finally, these results show that the appropriate conservation of ARCON96 is appeared in some conditions. Also these results seem to be in good agreement with NRC Regulatory Guide and positions

  3. Sensitivity Analysis of Onsite Atmospheric Dispersion Factor in Westinghouse type NPP in KOREA

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Chan; Yoon, Duk Joo; Song, Dong Soo [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    ARCON96 is a NRC licensed air dispersion model to evaluate onsite atmospheric relative concentration X/Q. The purpose of this paper is to provide some results for checking and testing the functionalities of ARCON96. Specially, this code is optimized to estimate a habitability of control room. Since NUREG 0737 issue, the control room habitability has been studied for a FSAR (Final Safety Analysis Report). Some assumptions and methodology is used in this paper. Some methodology is introduced in this paper. The reason of the selection of 2-loop Westinghouse NPP is because of carrying out the study project for the 2-loop Westinghouse NPP in the condition of the defueled NPP condition. Onsite atmospheric dispersion factor sensitivity is performed. Key impact factor is reviewed. Some results are below: a. Time averaged effect of X/Q is timely increased. b. ARCON96 code is more conservative at the low wind speed conditions. c. Building wake impact is significant in the condition of unstable atmospheric class with more than 7m/sec of wind speed. d. Plume meander effect is strong when the distance from the release point is small. e. The other plume meander effect is strong when the meander duration time is accumulated Finally, these results show that the appropriate conservation of ARCON96 is appeared in some conditions. Also these results seem to be in good agreement with NRC Regulatory Guide and positions.

  4. The Pribram, Lost City, Innisfree, and Neuschwanstein falls: An analysis of the atmospheric trajectories

    Science.gov (United States)

    Gritsevich, M. I.

    2008-10-01

    To date, several meteorites have been found for which their flight in the atmosphere was recorded by special fireball camera networks. Because of this, a thorough analysis of the instrumentally registered falls is of current importance. For such fireballs, not only the high-quality photo images of the motion in the atmosphere exist, but also the density and the shape of the meteor body fragments reached the Earth’s surface are known for sure. In the present study, for the Innisfree, Lost City, and Pribram fireballs, new models of the entry to the atmosphere have been built. The values of the ballistic coefficient and the mass-loss parameter providing the best approximation for the observations of the luminous trajectory segment with the analytical solution of the meteor physics equations have been obtained. From recent results of the numerical experiments on the supersonic airflow of bodies of various shapes, the preatmospheric masses of the fireballs, as well as the dynamic estimates of the mass at the other trajectory points, were obtained. In particular, the terminal mass of the fireballs in the lower segment of the analyzed trajectories is in good agreement with the total mass of the meteorite material recovered in all of the cases considered. Moreover, to calculate the acceleration of the meteor bodies, a new analytical formula has been suggested, which allows the obtained theoretical time dependencies of the velocity and altitude to be compared with the observational data.

  5. Observation and analysis of speciated atmospheric mercury in Shangri-La, Tibetan Plateau, China

    Science.gov (United States)

    Zhang, H.; Fu, X. W.; Lin, C.-J.; Wang, X.; Feng, X. B.

    2015-01-01

    This study reports the concentrations and potential sources of speciated atmospheric mercury at the Shangri-La Atmosphere Watch Regional Station (SAWRS), a pristine high-altitude site (3580 m a.s.l.) in Tibetan Plateau, China. Total gaseous mercury (TGM, defined as the sum of gaseous elemental mercury, GEM, and gaseous oxidized mercury, GOM), GOM and particulate-bound mercury (PBM) were monitored from November 2009 to November 2010 to investigate the characteristics and potential influence of the Indian summer monsoon (ISM) and the Westerlies on atmospheric transport of mercury. The mean concentrations (± standard deviation) of TGM, PBM and GOM were 2.55 ± 0.73 ng m-3, 38.82 ± 31.26 pg m-3 and 8.22 ± 7.90 pg m-3, respectively. A notable seasonal pattern of TGM concentrations was observed with higher concentrations at the beginning and the end of the ISM season. High TGM concentrations (> 2.5 ng m-3) were associated with the transport of dry air that carried regional anthropogenic emissions from both Chinese domestic and foreign (e.g., Myanmar, Bay of Bengal, and northern India) sources based on analysis of HYSPLIT4 back trajectories. Somewhat lower PBM and GOM levels during the ISM period were attributed to the enhanced wet scavenging. The high GOM and PBM were likely caused by local photo-chemical transformation under low RH and the domestic biofuel burning in cold seasons.

  6. Analysis of atmospheric particulate matter; application of optical and selected geochemical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Mastalerz, M.; Glikson, M.; Simpson, R.W. [Indiana University, Bloomington, IN (United States). Indiana Geological Survey

    1998-09-01

    An increase in particulate matter in the atmosphere has been shown to be linked to increased mortality but this relationship is poorly understood. Light microscopy, electron microscopy, electron microprobe, and micro-FTIR techniques have been applied to study atmospheric particulates in Brisbane, Australia as a part of a study on asthma. The particulate matter samples were collected daily from April to August 1992, and the sampling covered the autumn period which is typically a time of high asthma incidence in Brisbane. Volumetrically, most atmospheric particulate matter is less than 2{mu}m in size. The microscopic analysis reveals that this material is composed mainly of combusted and incompletely burned hydrocarbons from motor vehicle exhaust emissions, quiescent spores of Mucorales, soil bacteria, and inorganic matter in the form of quartz and other silicates. Elemental and functional group analyses confirm microscope identification, documenting carbon-rich, aromatic exhaust material, more aliphatic pollen and spore material and inorganic matter. Fungal spores dominate bioaerosol and are very abundant from the end of April through May to mid-June. The cytoplasmic content of pollens or fungaonly regarded as allergenic. Particulates from the exhaust emissions and crustal material in a sub-micrometer size range may act as carriers or dispersive mechanisms for cytoplasmic material from fungal spores and pollens, perhaps causing periods of the highest exhaust emission to be the most allergenic. 25 refs., 4 figs., 1 tab.

  7. Analysis of atmospheric paniculate matter; application of optical and selected geochemical techniques

    Science.gov (United States)

    Mastalerz, Maria; Glikson, M.; Simpson, R.W.

    1999-01-01

    An increase in participate matter in the atmosphere has been shown to be linked to increased mortality but this relationship is poorly understood. Light microscopy, electron microscopy, electron microprobe, and micro-FTIR techniques have been applied to study atmospheric particulates in Brisbane, Australia as a part of a study on asthma. The particulate matter samples were collected daily from April to August 1992, and the sampling covered the autumn period which is typically a time of high asthma incidence in Brisbane. Volumetrically, most atmospheric particulate matter is less than 2 ??m in size. The microscopic analysis reveals that this material is composed mainly of combusted and incompletely burned hydrocarbons from motor vehicle exhaust emissions, quiescent spores of Mucorales, soil bacteria, and inorganic matter in the form of quartz and other silicates. Elemental and functional group analyses confirm microscope identification, documenting carbon-rich, aromatic exhaust material, more aliphatic pollen and spore material and inorganic matter. Fungal spores dominate bioaerosol and are very abundant from the end of April through May to mid-June. The cytoplasmic content of pollens or fungal spores is commonly regarded as allergenic. Particulates from the exhaust emissions and crustal material in a sub-micrometer size range may act as carriers or dispersive mechanisms for cytoplasmic material from fungal spores and pollens, perhaps causing periods of the highest exhaust emission to be the most allergenic. ?? 1998 Elsevier Science B.V. All rights reserved.

  8. Electron beam chemistry in solid films of poly(vinyl alcohol): Exposures under vacuum and under N2 at atmospheric pressure; irradiation monitored by using infrared spectroscopy

    International Nuclear Information System (INIS)

    Pacansky, J.; Schneider, S.

    1990-01-01

    Thin films of poly(vinyl alcohol) (PVA) were exposed to a 25-kV electron beam under high vacuum conditions and to a 175-kV electron beam at atmospheric pressures of N 2 . The decomposition of PVA by the electron beam sequentially formed materials that had polyketone- and polyethylene-like structures, respectively. Contrary to previous reports we show that the ketone groups formed as a result of the electron beam exposure are not due to an oxidation step by molecular oxygen. Damage cross sections for the electron beam decomposition (at 25 kV) were determined for PVA and the polyketone, and G values were determined for decomposition of -OH groups and formation of ketone functional groups

  9. Atmospheric mercury pollution around a chlor-alkali plant in Flix (NE Spain): an integrated analysis.

    Science.gov (United States)

    Esbrí, José M; López-Berdonces, Miguel Angel; Fernández-Calderón, Sergio; Higueras, Pablo; Díez, Sergi

    2015-04-01

    An integrated analysis approach has been applied to a mercury (Hg) case study on a chlor-alkali plant located in the Ebro River basin, close to the town of Flix (NE Spain). The study focused on atmospheric Hg and its incorporation in soils and lichens close to a mercury cell chlor-alkali plant (CAP), which has been operating since the end of the 19th century. Atmospheric Hg present in the area was characterized by means of seven total gaseous mercury (TGM) surveys carried out from 2007 to 2012. Surveys were carried out by car, walking, and at fixed locations, and covered an area of some 12 km(2) (including the CAP area, the village in which workers live, Flix town, and the Sebes Wildlife Reserve). Finally, an atmospheric Hg dispersion model was developed with ISC-AERMOD software validated by a lichen survey of the area. The results for the atmospheric compartment seem to indicate that the Flix area currently has the highest levels of Hg pollution in Spain on the basis of the extremely high average concentrations in the vicinity of the CAP (229 ng m(-3)). Moreover, the Hg(0) plume affects Flix town center to some extent, with values well above the international thresholds for residential areas. Wet and dry Hg deposition reached its highest values on the banks of the Ebro River, and this contributes to increased soil contamination (range 44-12,900 ng g(-1), average 775 ng g(-1)). A good fit was obtained between anomalous areas indicated by lichens and the dispersion model for 1 year.

  10. Black carbon ageing in the Canadian Centre for Climate modelling and analysis atmospheric general circulation model

    Directory of Open Access Journals (Sweden)

    B. Croft

    2005-01-01

    Full Text Available Black carbon (BC particles in the atmosphere have important impacts on climate. The amount of BC in the atmosphere must be carefully quantified to allow evaluation of the climate effects of this type of aerosol. In this study, we present the treatment of BC aerosol in the developmental version of the 4th generation Canadian Centre for Climate modelling and analysis (CCCma atmospheric general circulation model (AGCM. The focus of this work is on the conversion of insoluble BC to soluble/mixed BC by physical and chemical ageing. Physical processes include the condensation of sulphuric and nitric acid onto the BC aerosol, and coagulation with more soluble aerosols such as sulphates and nitrates. Chemical processes that may age the BC aerosol include the oxidation of organic coatings by ozone. Four separate parameterizations of the ageing process are compared to a control simulation that assumes no ageing occurs. These simulations use 1 an exponential decay with a fixed 24h half-life, 2 a condensation and coagulation scheme, 3 an oxidative scheme, and 4 a linear combination of the latter two ageing treatments. Global BC burdens are 2.15, 0.15, 0.11, 0.21, and 0.11TgC for the control run, and four ageing schemes, respectively. The BC lifetimes are 98.1, 6.6, 5.0, 9.5, and 4.9 days, respectively. The sensitivity of modelled BC burdens, and concentrations to the factor of two uncertainty in the emissions inventory is shown to be greater than the sensitivity to the parameterization used to represent the BC ageing, except for the oxidation based parameterization. A computationally efficient parameterization that represents the processes of condensation, coagulation, and oxidation is shown to simulate BC ageing well in the CCCma AGCM. As opposed to the globally fixed ageing time scale, this treatment of BC ageing is responsive to varying atmospheric composition.

  11. Deciphering the atmospheric composition of WASP-12b: A comprehensive analysis of its dayside emission

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, Kevin B.; Bean, Jacob L. [Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Madhusudhan, Nikku [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Harrington, Joseph, E-mail: kbs@uchicago.edu [Planetary Sciences Group, Department of Physics, University of Central Florida, Orlando, FL 32816-2385 (United States)

    2014-08-10

    WASP-12b was the first planet reported to have a carbon-to-oxygen ratio (C/O) greater than one in its dayside atmosphere. However, recent work to further characterize its atmosphere and confirm its composition has led to incompatible measurements and divergent conclusions. Additionally, the recent discovery of stellar binary companions ∼1'' from WASP-12 further complicates the analyses and subsequent interpretations. We present a uniform analysis of all available Hubble and Spitzer Space Telescope secondary-eclipse data, including previously unpublished Spitzer measurements at 3.6 and 4.5 μm. The primary controversy in the literature has centered on the value and interpretation of the eclipse depth at 4.5 μm. Our new measurements and analyses confirm the shallow eclipse depth in this channel, as first reported by Campo and collaborators and used by Madhusudhan and collaborators to infer a carbon-rich composition. To explain WASP-12b's observed dayside emission spectrum, we implemented several recent retrieval approaches. We find that when we exclude absorption due to C{sub 2}H{sub 2} and HCN, which are not universally considered in the literature, our models require implausibly large atmospheric CO{sub 2} abundances, regardless of the C/O. By including C{sub 2}H{sub 2} and HCN in our models, we find that a physically plausible carbon-rich solution achieves the best fit to the available photometric and spectroscopic data. In comparison, the best-fit oxygen-rich models have abundances that are inconsistent with the chemical equilibrium expectations for hydrogen-dominated atmospheres and are 670 times less probable. Our best-fit solution is also 7.3 × 10{sup 6} times more probable than an isothermal blackbody model.

  12. Causal Analysis of the Unanticipated Extremity Exposure at HFEF

    Energy Technology Data Exchange (ETDEWEB)

    David E. James; Charles R. Posegate; Thomas P. Zahn; Alan G. Wagner

    2011-11-01

    This report covers the unintended extremity exposure to an operator while handling a metallurgical mount sample of irradiated fuel following an off-scale high beta radiation reading of the sample. The decision was made to continue working after the meter indicated high off-scale by the HPT Supervisor, which resulted in the operator at the next operation being exposed.

  13. Complexities of sibling analysis when exposures and outcomes change with time and birth order

    OpenAIRE

    Sudan, M; Kheifets, LI; Arah, OA; Divan, HA; Olsen, J

    2014-01-01

    In this study, we demonstrate the complexities of performing a sibling analysis with a re-examination of associations between cell phone exposures and behavioral problems observed previously in the Danish National Birth Cohort. Children (52,680; including 5441 siblings) followed up to age 7 were included. We examined differences in exposures and behavioral problems between siblings and non-siblings and by birth order and birth year. We estimated associations between cell phone exposures and b...

  14. Analysis of atmospheric concentrations of radon and thoron using beta counting technique

    International Nuclear Information System (INIS)

    Islam, G.S.; Basunia, S.M.

    1995-05-01

    This paper presents a detailed theory and experimental procedure for measurement and analysis of mixed radon and thoron in the environment. The technique has been successfully applied to the study of seasonal variations of radon and thoron in Rajshahi atmosphere during the years 1989-1991. The maximum radon concentration in outdoor air was observed in the winter from December to January while the indoor radon concentration was found to be maximum during the monsoon months of July and August. The implication of results is briefly discussed in the paper. (author). 4 refs, 6 figs, 2 tabs

  15. Process analysis of the modelled 3-D mesoscale impact of aircraft emissions on the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, J; Ebel, A; Lippert, E; Petry, H [Koeln Univ. (Germany). Inst. fuer Geophysik und Meterorologie

    1998-12-31

    A mesoscale chemistry transport model is applied to study the impact of aircraft emissions on the atmospheric trace gas composition. A special analysis of the simulations is conducted to separate the effects of chemistry, transport, diffusion and cloud processes on the transformation of the exhausts of a subsonic fleet cruising over the North Atlantic. The aircraft induced ozone production strongly depends on the tropopause height and the cruise altitude. Aircraft emissions may undergo an effective downward transport under the influence of stratosphere-troposphere exchange activity. (author) 12 refs.

  16. Process analysis of the modelled 3-D mesoscale impact of aircraft emissions on the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, J.; Ebel, A.; Lippert, E.; Petry, H. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meterorologie

    1997-12-31

    A mesoscale chemistry transport model is applied to study the impact of aircraft emissions on the atmospheric trace gas composition. A special analysis of the simulations is conducted to separate the effects of chemistry, transport, diffusion and cloud processes on the transformation of the exhausts of a subsonic fleet cruising over the North Atlantic. The aircraft induced ozone production strongly depends on the tropopause height and the cruise altitude. Aircraft emissions may undergo an effective downward transport under the influence of stratosphere-troposphere exchange activity. (author) 12 refs.

  17. Analysis of Radio Frequency Blackout for a Blunt-Body Capsule in Atmospheric Reentry Missions

    Directory of Open Access Journals (Sweden)

    Yusuke Takahashi

    2016-01-01

    Full Text Available A numerical analysis of electromagnetic waves around the atmospheric reentry demonstrator (ARD of the European Space Agency (ESA in an atmospheric reentry mission was conducted. During the ARD mission, which involves a 70% scaled-down configuration capsule of the Apollo command module, radio frequency blackout and strong plasma attenuation of radio waves in communications with data relay satellites and air planes were observed. The electromagnetic interference was caused by highly dense plasma derived from a strong shock wave generated in front of the capsule because of orbital speed during reentry. In this study, the physical properties of the plasma flow in the shock layer and wake region of the ESA ARD were obtained using a computational fluid dynamics technique. Then, electromagnetic waves were expressed using a frequency-dependent finite-difference time-domain method using the plasma properties. The analysis model was validated based on experimental flight data. A comparison of the measured and predicted results showed good agreement. The distribution of charged particles around the ESA ARD and the complicated behavior of electromagnetic waves, with attenuation and reflection, are clarified in detail. It is suggested that the analysis model could be an effective tool for investigating radio frequency blackout and plasma attenuation in radio wave communication.

  18. Dynamics and causalities of atmospheric and oceanic data identified by complex networks and Granger causality analysis

    Science.gov (United States)

    Charakopoulos, A. K.; Katsouli, G. A.; Karakasidis, T. E.

    2018-04-01

    Understanding the underlying processes and extracting detailed characteristics of spatiotemporal dynamics of ocean and atmosphere as well as their interaction is of significant interest and has not been well thoroughly established. The purpose of this study was to examine the performance of two main additional methodologies for the identification of spatiotemporal underlying dynamic characteristics and patterns among atmospheric and oceanic variables from Seawatch buoys from Aegean and Ionian Sea, provided by the Hellenic Center for Marine Research (HCMR). The first approach involves the estimation of cross correlation analysis in an attempt to investigate time-lagged relationships, and further in order to identify the direction of interactions between the variables we performed the Granger causality method. According to the second approach the time series are converted into complex networks and then the main topological network properties such as degree distribution, average path length, diameter, modularity and clustering coefficient are evaluated. Our results show that the proposed analysis of complex network analysis of time series can lead to the extraction of hidden spatiotemporal characteristics. Also our findings indicate high level of positive and negative correlations and causalities among variables, both from the same buoy and also between buoys from different stations, which cannot be determined from the use of simple statistical measures.

  19. Instrumental neutron activation analysis of dry atmospheric fall-out and rain-water

    International Nuclear Information System (INIS)

    Schutyser, P.; Maenhaut, W.; Dams, R.

    1978-01-01

    An automated precipitation sampler and an instrumental neutron activation analysis (i.n.a.a.) method for the determination of some major and trace elements in dry atmospheric fall-out and rain-water are presented. The sampler features a rain detector which makes separate collections of dry atmospheric fall-out and rain-water possible. The sampler is equipped with u.v. lamps in order to avoid algal growth during extended collection periods. After collection, the samples are separated into water-soluble and insoluble fractions. The soluble fraction is preconcentrated before analysis by freeze-drying. The i.n.a.a. method involves the measurement of both short- and long-lived radioactivities so that a total of 35 elements can be determined. The possibility of losses during freeze-drying and the accuracy of the i.n.a.a. method were investigated for 7 elements by analysis of a soluble fraction with an independent method, viz. inductively coupled plasma atomic emission spectrometry. (Auth.)

  20. Arbuscular mycorrhiza formation and its function under elevated atmospheric O3: A meta-analysis.

    Science.gov (United States)

    Wang, Shuguang; Augé, Robert M; Toler, Heather D

    2017-07-01

    We quantitatively evaluated the effects of elevated O 3 on arbuscular mycorrhiza (AM) formation and on AM role in promoting plant growth in regard to several moderating variables (O 3 levels, O 3 exposure duration, plant types, AM fungi family, and additional stress) by means of meta-analysis of published data. The analysis consisted of 117 trials representing 20 peer-reviewed articles and 16 unpublished trials. Relative to non-mycorrhizal controls, AM inoculation did not significantly alter plant growth (shoot biomass, root biomass, total biomass and plant height) when O 3 concentration was less than 80 ppb, but at concentrations above 80 ppb symbiosis was associated with increases of 68% in shoot biomass and 131% in root biomass. AM effects on plant growth were affected by the duration of O 3 exposure but did not differ much with AM fungi taxa or plant type. AM symbiosis has also led to higher yields under O 3 stress, relative to the non-mycorrhizal plants, and the AM effects have been more pronounced as O 3 concentration increases. As with biomass, AM effects on yield have been affected by the duration of O 3 exposure, with the greatest increase (100%) occurring at 61-90 d. AM-induced promotion of yield differed with fungal species but not with plant type or other abiotic stress. Colonization of roots by AM fungi has been negatively affected by elevated O 3 compared to ambient O 3 ; total mycorrhizal colonization rate (MCR), arbuscular MCR, vesicular MCR and hyphal coil MCR declined as O 3 levels rose. AM colonization rates were affected by duration of O 3 exposure, plant type, AM fungal taxa and other concurrent stresses in most cases. The analysis showed that AM inoculation has the potential to ameliorate detrimental effects of elevated O 3 on plant growth and productivity, despite colonization rates being negatively affected by elevated O 3 . Copyright © 2017. Published by Elsevier Ltd.

  1. Simultaneous analysis of gaseous and particulate sulphur in the atmosphere by x-ray fluorescence spectrometry

    International Nuclear Information System (INIS)

    Matsuda, Yatsuka; Mamuro, Tetsuo

    1975-01-01

    An analytical technique for the simultaneous measurements of the atmospheric concentrations of SO 2 gas and sulphur absorbed by aerosol particles has been developed. Aerosol particles are collected on membrane filter and at the same time SO 2 gas is captured on alkali impregnated filter. The sulphur content in each filter is measured by an energy dispersive X -ray fluorescence spectrometer consisting of a Si(Li) semiconductor detector connected to a multi-channel pulse height analyzer and an excitation source of 55 Fe. Two methods are acceptable for the determination of the sulphur content in impregnated filter by X-ray fluorescence analysis. In the first method X-ray fluorescence analysis is made after the collected sulphur gas diffused and distributed uniformly enough throughout the filter, and in the second method X-ray fluorescence analysis gas to be finished before the diffusion of the collected sulphur becomes appreciable. (author)

  2. Pesticide Flow Analysis to Assess Human Exposure in Greenhouse Flower Production in Colombia

    Directory of Open Access Journals (Sweden)

    Claudia R. Binder

    2013-03-01

    Full Text Available Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area.

  3. Risk assessment of exposure to radon concentration in indoor atmosphere and drinking water of Shimoga city, Karnataka, India

    International Nuclear Information System (INIS)

    Rangaswamy, D.R.; Sannappa, J.; Srinivasa, E.

    2016-01-01

    The exposure of population to natural sources of radiation has become an important issue in terms of radiological protection. The major contribution of dose from natural radiation in normal background regions arises due to inhalation of alpha-emitting radon and thoron, and their progenies, which are ubiquitous in both indoor and outdoor environs. The aim of the present study is to measure indoor radon, thoron and their progeny levels in the dwellings of Shimoga city and radon concentration in drinking water and to estimate the annual effective dose. The indoor concentration of radon, thoron and their progeny was measured using Solid-State Nuclear Track Detectors (SSNTDs) based twin chamber dosimeter cups. The 222 Rn concentration in drinking water was estimated by the Emanometry technique

  4. Atmospheric pollution

    International Nuclear Information System (INIS)

    Lambrozo, J.; Guillossou, G.

    2008-01-01

    The atmosphere is the reservoir of numerous pollutants (nitrogen oxides, sulfur oxides, carbon oxides, particulates, volatile organic compounds, polycyclic aromatic hydrocarbons) from natural origin or anthropogenic origin ( industry, transport, agriculture, district heating). With epidemiologic studies the atmospheric pollution is associated with an increase of respiratory and cardiovascular diseases. At the european level, the technological progress, the legislation have allowed a reduction of pollutant emissions, however these efforts have to be continued because the sanitary impact of atmospheric pollution must not be underestimated, even if the risks appear less important that these ones in relation with tobacco, inside pollution or others factors of cardiovascular risks. Indeed, on these last factors an individual action is possible for the exposure to air pollution people have no control. (N.C.)

  5. Virtual reality exposure therapy for anxiety disorders: A meta-analysis

    NARCIS (Netherlands)

    Powers, M.B.; Emmelkamp, P.M.G.

    2008-01-01

    There is now a substantial literature investigating virtual reality exposure therapy (VRET) as a viable treatment option for anxiety disorders. In this meta-analysis we provide effect size estimates for virtual reality treatment in comparison to in vivo exposure and control conditions (waitlist,

  6. Analysis of the experimental data of air pollution using atmospheric dispersion modeling and rough set

    International Nuclear Information System (INIS)

    Halfa, I.K.I

    2008-01-01

    This thesis contains four chapters and list of references:In chapter 1, we introduce a brief survey about the atmospheric concepts and the topological methods for data analysis.In section 1.1, we give introduce a general introduction. We recall some of atmospheric fundamentals in Section 1.2. Section 1.3, shows the concepts of modern topological methods for data analysis.In chapter 2, we have studied the properties of atmosphere and focus on concept of Rough set and its properties. This concepts of rough set has been applied to analyze the atmospheric data.In section 2.1, we introduce a general introduction about concept of rough set and properties of atmosphere. Section 2.2 focuses on the concept of rough set and its properties and generalization of approximation of rough set theory by using topological space. In section 2.3 we have studied the stabilities of atmosphere for Inshas location for all seasons using different schemes and compared these schemes using statistical and rough set methods. In section 2.4, we introduce mixing height of plume for all seasons. Section 2.5 introduced seasonal surface layer turbulence processes for Inshas location. Section 2.6 gives a comparison between the seasonal surface layer turbulence processes for Inshas location and for different locations using rough set theory.In chapter 3 we focus on the concept of variable precision rough set (VPRS) and its properties and using it to compare, between the estimated and observed data of the concentration of air pollution for Inshas location. In Section 3.1 we introduce a general introduction about VPRS and air pollution. In Section 3.2 we have focused on the concept and properties of VPRS. In Section 3.3 we have introduced a method to estimate the concentration of air pollution for Inshas location using Gaussian plume model. Section 3.4 has showed the experimental data. The estimated data have been compared with the observed data using statistical methods in Section 3.5. In Section 3

  7. The effect of meteorological data on atmospheric pressure loading corrections in VLBI data analysis

    Science.gov (United States)

    Balidakis, Kyriakos; Glaser, Susanne; Karbon, Maria; Soja, Benedikt; Nilsson, Tobias; Lu, Cuixian; Anderson, James; Liu, Li; Andres Mora-Diaz, Julian; Raposo-Pulido, Virginia; Xu, Minghui; Heinkelmann, Robert; Schuh, Harald

    2015-04-01

    Earth's crustal deformation is a manifestation of numerous geophysical processes, which entail the atmosphere and ocean general circulation and tidal attraction, climate change, and the hydrological circle. The present study deals with the elastic deformations induced by atmospheric pressure variations. At geodetic sites, APL (Atmospheric Pressure Loading) results in displacements covering a wide range of temporal scales which is undesirable when rigorous geodetic/geophysical analysis is intended. Hence, it is of paramount importance that the APL signal are removed at the observation level in the space geodetic data analysis. In this study, elastic non-tidal components of loading displacements were calculated in the local topocentric frame for all VLBI (Very Long Baseline Interferometry) stations with respect to the center-of-figure of the solid Earth surface and the center-of-mass of the total Earth system. The response of the Earth to the load variation at the surface was computed by convolving Farrell Green's function with the homogenized in situ surface pressure observations (in the time span 1979-2014) after the subtraction of the reference pressure and the S1, S2 and S3 thermal tidal signals. The reference pressure was calculated through a hypsometric adjustment of the absolute pressure level determined from World Meteorological Organization stations in the vicinity of each VLBI observatory. The tidal contribution was calculated following the 2010 International Earth Rotation and Reference Systems Service conventions. Afterwards, this approach was implemented into the VLBI software VieVS@GFZ and the entirety of available VLBI sessions was analyzed. We rationalize our new approach on the basis that the potential error budget is substantially reduced, since several common errors are not applicable in our approach, e.g. those due to the finite resolution of NWM (Numerical Weather Models), the accuracy of the orography model necessary for adjusting the former as

  8. Exposure calculation code module for reactor core analysis: BURNER

    Energy Technology Data Exchange (ETDEWEB)

    Vondy, D.R.; Cunningham, G.W.

    1979-02-01

    The code module BURNER for nuclear reactor exposure calculations is presented. The computer requirements are shown, as are the reference data and interface data file requirements, and the programmed equations and procedure of calculation are described. The operating history of a reactor is followed over the period between solutions of the space, energy neutronics problem. The end-of-period nuclide concentrations are determined given the necessary information. A steady state, continuous fueling model is treated in addition to the usual fixed fuel model. The control options provide flexibility to select among an unusually wide variety of programmed procedures. The code also provides user option to make a number of auxiliary calculations and print such information as the local gamma source, cumulative exposure, and a fine scale power density distribution in a selected zone. The code is used locally in a system for computation which contains the VENTURE diffusion theory neutronics code and other modules.

  9. Exposure calculation code module for reactor core analysis: BURNER

    International Nuclear Information System (INIS)

    Vondy, D.R.; Cunningham, G.W.

    1979-02-01

    The code module BURNER for nuclear reactor exposure calculations is presented. The computer requirements are shown, as are the reference data and interface data file requirements, and the programmed equations and procedure of calculation are described. The operating history of a reactor is followed over the period between solutions of the space, energy neutronics problem. The end-of-period nuclide concentrations are determined given the necessary information. A steady state, continuous fueling model is treated in addition to the usual fixed fuel model. The control options provide flexibility to select among an unusually wide variety of programmed procedures. The code also provides user option to make a number of auxiliary calculations and print such information as the local gamma source, cumulative exposure, and a fine scale power density distribution in a selected zone. The code is used locally in a system for computation which contains the VENTURE diffusion theory neutronics code and other modules

  10. [Sample preparation methods for chromatographic analysis of organic components in atmospheric particulate matter].

    Science.gov (United States)

    Hao, Liang; Wu, Dapeng; Guan, Yafeng

    2014-09-01

    The determination of organic composition in atmospheric particulate matter (PM) is of great importance in understanding how PM affects human health, environment, climate, and ecosystem. Organic components are also the scientific basis for emission source tracking, PM regulation and risk management. Therefore, the molecular characterization of the organic fraction of PM has become one of the priority research issues in the field of environmental analysis. Due to the extreme complexity of PM samples, chromatographic methods have been the chief selection. The common procedure for the analysis of organic components in PM includes several steps: sample collection on the fiber filters, sample preparation (transform the sample into a form suitable for chromatographic analysis), analysis by chromatographic methods. Among these steps, the sample preparation methods will largely determine the throughput and the data quality. Solvent extraction methods followed by sample pretreatment (e. g. pre-separation, derivatization, pre-concentration) have long been used for PM sample analysis, and thermal desorption methods have also mainly focused on the non-polar organic component analysis in PM. In this paper, the sample preparation methods prior to chromatographic analysis of organic components in PM are reviewed comprehensively, and the corresponding merits and limitations of each method are also briefly discussed.

  11. Analysis of Vertical Weighting Functions for Lidar Measurements of Atmospheric CO2 and O2

    Science.gov (United States)

    Kooi, S.; Mao, J.; Abshire, J. B.; Browell, E. V.; Weaver, C. J.; Kawa, S. R.

    2011-12-01

    Several NASA groups have developed integrated path differential absorption (IPDA) lidar approaches to measure atmospheric CO2 concentrations from space as a candidates for NASA's ASCENDS space mission. For example, the Goddard CO2 Sounder approach uses two pulsed lasers to simultaneously measure both CO2 and O2 absorption in the vertical path to the surface at a number of wavelengths across a CO2 line near 1572 nm and an O2 line doublet near 764 nm. The measurements of CO2 and O2 absorption allow computing their vertically weighted number densities and then their ratios for estimating CO2 concentration relative to dry air. Since both the CO2 and O2 densities and their absorption line-width decrease with altitude, the absorption response (or weighting function) varies with both altitude and absorption wavelength. We have used some standard atmospheres and HITRAN 2008 spectroscopy to calculate the vertical weighting functions for two CO2 lines near 1571 nm and the O2 lines near 764.7 and 1260 nm for candidate online wavelength selections for ASCENDS. For CO2, the primary candidate on-line wavelengths are 10-12 pm away from line center with the weighting function peaking in the atmospheric boundary layer to measure CO2 sources and sinks at the surface. Using another on-line wavelength 3-5 pm away from line center allows the weighting function to peak in the mid- to upper troposphere, which is sensitive to CO2 transport in the free atmosphere. The Goddard CO2 sounder team developed an airborne precursor version of a space instrument. During the summers of 2009, 2010 and 2011 it has participated in airborne measurement campaigns over a variety of different sites in the US, flying with other NASA ASCENDS lidar candidates along with accurate in-situ atmospheric sensors. All flights used altitude patterns with measurements at steps in altitudes between 3 and 13 km, along with spirals from 13 km altitude to near the surface. Measurements from in-situ sensors allowed an

  12. Seasonal response of photosynthetic electron transport and energy dissipation in the eighth year of exposure to elevated atmospheric CO2 (FACE) in Pinus taeda (loblolly pine)

    International Nuclear Information System (INIS)

    Logan, B.A.; Combs, A.; Kent, R.; Stanley, L.; Myers, K.; Tissue, D.T.; Western Sydney Univ., Richmond, NSW

    2009-01-01

    This study investigated the biological adaptation of loblolly pine following long-term seasonal exposure to elevated carbon dioxide (CO 2 ) partial pressures (pCO 2 ). Exposure to elevated atmospheric CO 2 (pCO 2 ) usually results in significant stimulation in light-saturated rates of photosynthetic CO 2 assimilation. Plants are protected against photoinhibition by biochemical processes known as photoprotection, including energy dissipation, which converts excess absorbed light energy into heat. This study was conducted in the eighth year of exposure to elevated pCO 2 at the Duke FACE site. The effect of elevated pCO 2 on electron transport and energy dissipation in the pine trees was examined by coupling the analyses of the capacity for photosynthetic oxygen (O 2 ) evolution, chlorophyll fluorescence emission and photosynthetic pigment composition with measurements of net photosynthetic CO 2 assimilation (Asat). During the summer growing season, Asat was 50 per cent higher in current-year needles and 24 per cent higher in year-old needles in elevated pCO 2 in comparison with needles of the same age cohort in ambient pCO 2 . Thus, older needles exhibited greater photosynthetic down-regulation than younger needles in elevated pCO 2 . In the winter, Asat was not significantly affected by growth pCO 2 . Asat was lower in winter than in summer. Growth at elevated pCO 2 had no significant effect on the capacity for photosynthetic oxygen evolution, photosystem 2 efficiencies, chlorophyll content or the size and conversion state of the xanthophyll cycle, regardless of season or needle age. There was no evidence that photosynthetic electron transport or photoprotective energy dissipation responded to compensate for the effects of elevated pCO 2 on Calvin cycle activity. 73 refs., 4 figs

  13. Dispersion analysis of the Pn -Pn-1DG mixed finite element pair for atmospheric modelling

    Science.gov (United States)

    Melvin, Thomas

    2018-02-01

    Mixed finite element methods provide a generalisation of staggered grid finite difference methods with a framework to extend the method to high orders. The ability to generate a high order method is appealing for applications on the kind of quasi-uniform grids that are popular for atmospheric modelling, so that the method retains an acceptable level of accuracy even around special points in the grid. The dispersion properties of such schemes are important to study as they provide insight into the numerical adjustment to imbalance that is an important component in atmospheric modelling. This paper extends the recent analysis of the P2 - P1DG pair, that is a quadratic continuous and linear discontinuous finite element pair, to higher polynomial orders and also spectral element type pairs. In common with the previously studied element pair, and also with other schemes such as the spectral element and discontinuous Galerkin methods, increasing the polynomial order is found to provide a more accurate dispersion relation for the well resolved part of the spectrum but at the cost of a number of unphysical spectral gaps. The effects of these spectral gaps are investigated and shown to have a varying impact depending upon the width of the gap. Finally, the tensor product nature of the finite element spaces is exploited to extend the dispersion analysis into two-dimensions.

  14. Exposure to Atmospheric PMS,PAHS,PCDD/FS and Metals Nearan Open Air Waste Burningsite in Beirut

    International Nuclear Information System (INIS)

    Baalbaki, R.; El Hage, R.; Nassar, J.; Shihadeh, A.; Saliba, N.; Gerard, K.; Saliba, N.; Zaarour, R.; Abboud, M.; Farah, W.; Khalaf Kairouz, L.

    2016-01-01

    Since July 2015, Lebanon has experienced the worst solid waste management crisis in its history. Consequently, open-air waste burning in the vicinity of highly populated areas in Beirut has become a common practice. This study evaluates the effects of open-air dumping and burning on local air quality and public health. The levels of particulate matter(PM10, PM2.5), gaseous and particle-bound polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo- dioxins and furans (PCDD/Fs), and particle-bound metals at a residence close to waste burning are reported. Concentrations, determined between October 2 and December 2, 2015, were compared either to previous measurements or to measurements taken away from a nearby burning incident,and after it had rained. Subsequently, the cancer risk due to exposure to these chemicals was assessed. Results showed alarming increases in pollutant concentrations which was translated into an increase inshort-term cancer risk from about 1 to 20 people per million on the days when waste was being burned. Findings were shared with the public to warn the community against the dangers of waste mismanagement, and underline the obvious need for solid waste management at the governmental and municipal levels. (author

  15. Atmospheric Pressure and Abdominal Aortic Aneurysm Rupture: Results From a Time Series Analysis and Case-Crossover Study.

    Science.gov (United States)

    Penning de Vries, Bas B L; Kolkert, Joé L P; Meerwaldt, Robbert; Groenwold, Rolf H H

    2017-10-01

    Associations between atmospheric pressure and abdominal aortic aneurysm (AAA) rupture risk have been reported, but empirical evidence is inconclusive and largely derived from studies that did not account for possible nonlinearity, seasonality, and confounding by temperature. Associations between atmospheric pressure and AAA rupture risk were investigated using local meteorological data and a case series of 358 patients admitted to hospital for ruptured AAA during the study period, January 2002 to December 2012. Two analyses were performed-a time series analysis and a case-crossover study. Results from the 2 analyses were similar; neither the time series analysis nor the case-crossover study showed a significant association between atmospheric pressure ( P = .627 and P = .625, respectively, for mean daily atmospheric pressure) or atmospheric pressure variation ( P = .464 and P = .816, respectively, for 24-hour change in mean daily atmospheric pressure) and AAA rupture risk. This study failed to support claims that atmospheric pressure causally affects AAA rupture risk. In interpreting our results, one should be aware that the range of atmospheric pressure observed in this study is not representative of the atmospheric pressure to which patients with AAA may be exposed, for example, during air travel or travel to high altitudes in the mountains. Making firm claims regarding these conditions in relation to AAA rupture risk is difficult at best. Furthermore, despite the fact that we used one of the largest case series to date to investigate the effect of atmospheric pressure on AAA rupture risk, it is possible that this study is simply too small to demonstrate a causal link.

  16. Nuclear microprobe analysis and source apportionment of individual atmospheric aerosol particles

    International Nuclear Information System (INIS)

    Artaxo, P.; Rabello, M.L.C.; Watt, F.; Grime, G.; Swietlicki, E.

    1993-01-01

    In atmospheric aerosol reserach, one key issue is to determine the sources of the airborne particles. Bulk PIXE analysis coupled with receptor modeling provides a useful, but limited view of the aerosol sources influencing one particular site or sample. The scanning nuclear microprobe (SNM) technique is a microanalytical technique that gives unique information on individual aerosol particles. In the SNM analyses a 1.0 μm size 2.4 MeV proton beam from the Oxford SNM was used. The trace elements with Z>11 were measured by the particle induced X-ray emission (PIXE) method with detection limits in the 1-10 ppm range. Carbon, nitrogen and oxygen are measured simultaneously using Rutherford backscattering spectrometry (RBS). Atmospheric aerosol particles were collected at the Brazilian Antarctic Station and at biomass burning sites in the Amazon basin tropical rain forest in Brazil. In the Antarctic samples, the sea-salt aerosol particles were clearly predominating, with NaCl and CaSO 4 as major compounds with several trace elements as Al, Si, P, K, Mn, Fe, Ni, Cu, Zn, Br, Sr, and Pb. Factor analysis of the elemental data showed the presence of four components: 1) Soil dust particles; 2) NaCl particles; 3) CaSO 4 with Sr; and 4) Br and Mg. Strontium, observed at 20-100 ppm levels, was always present in the CaSO 4 particles. The hierarchical cluster procedure gave results similar to the ones obtained through factor analysis. For the tropical rain forest biomass burning aerosol emissions, biogenic particles with a high organic content dominate the particle population, while K, P, Ca, Mg, Zn, and Si are the dominant elements. Zinc at 10-200 ppm is present in biogenic particles rich in P and K. The quantitative aspects and excellent detection limits make SNM analysis of individual aerosol particles a very powerful analytical tool. (orig.)

  17. Leaf quality and insect herbivory in model tropical plant communities after long-term exposure to elevated atmospheric CO2.

    Science.gov (United States)

    Arnone, J A; Zaller, J G; Körner, Ch; Ziegler, C; Zandt, H

    1995-09-01

    Results from laboratory feeding experiments have shown that elevated atmospheric carbon dioxide can affect interactions between plants and insect herbivores, primarily through changes in leaf nutritional quality occurring at elevated CO 2 . Very few data are available on insect herbivory in plant communities where insects can choose among species and positions in the canopy in which to feed. Our objectives were to determine the extent to which CO 2 -induced changes in plant communities and leaf nutritional quality may affect herbivory at the level of the entire canopy. We introduced equivalent populations of fourth instar Spodoptera eridania, a lepidopteran generalist, to complex model ecosystems containing seven species of moist tropical plants maintained under low mineral nutrient supply. Larvae were allowed to feed freely for 14 days, by which time they had reached the seventh instar. Prior to larval introductions, plant communities had been continuously exposed to either 340 μl CO 2 l -1 or to 610 μl CO 2 l -1 for 1.5 years. No major shifts in leaf nutritional quality [concentrations of N, total non-structural carbohydrates (TNC), sugar, and starch; ratios of: C/N, TNC/N, sugar/N, starch/N; leaf toughness] were observed between CO 2 treatments for any of the species. Furthermore, no correlations were observed between these measures of leaf quality and leaf biomass consumption. Total leaf area and biomass of all plant communities were similar when caterpillars were introduced. However, leaf biomass of some species was slightly greater-and for other species slightly less (e.g. Cecropia peltata)-in communities exposed to elevated CO 2 . Larvae showed the strongest preference for C. peltata leaves, the plant species that was least abundant in all communites, and fed relatively little on plants species which were more abundant. Thus, our results indicate that leaf tissue quality, as described by these parameters, is not necessarily affected by elevated CO 2 under

  18. Multiplex gas chromatography: an alternative concept for gas chromatographic analysis of planetary atmospheres

    Science.gov (United States)

    Valentin, J. R.

    1989-01-01

    -Cassini entry probe, which is being jointly planned by NASA and the European Space Agency (ESA), might be launched as early as 1994. As in the Pioneer mission, limited time--perhaps only 3-4 h--will be available for the completion of all analyses while the probe descends through the atmosphere. A conventional GC or GC-MS system would be able to analyze no more than two aerosol and two gas samples during the probe's descent. Conventional GC also is limited by the sensitivity of the detector and by the sample volume. For the Titan mission, the sensitivity problems will be worse because the atmospheric pressure at the time of instrument deployment is expected to be of such limitations, alternative GC analysis techniques have been investigated for future NASA missions. Multiplex gas chromatography has been investigated as a possible candidate for chemical analysis within a spacecraft or other restricted environment, and chemical modulators have been developed and used when needed with this technique to reduce the size and weight of the instrumentation. Also, several new multiplex techniques have been developed for use in specific applications.

  19. Understanding and Forecasting Upper Atmosphere Nitric Oxide Through Data Mining Analysis of TIMED/SABER Data

    Science.gov (United States)

    Flynn, S.; Knipp, D. J.; Matsuo, T.; Mlynczak, M. G.; Hunt, L. A.

    2017-12-01

    Storm time energy input to the upper atmosphere is countered by infrared radiative emissions from nitric oxide (NO). The temporal profile of these energy sources and losses strongly control thermospheric density profiles, which in turn affect the drag experienced by low Earth orbiting satellites. Storm time processes create NO. In some extreme cases an overabundance of NO emissions unexpectedly decreases atmospheric temperature and density to lower than pre-storm values. Quantifying the spatial and temporal variability of the NO emissions using eigenmodes will increase the understanding of how upper atmospheric NO behaves, and could be used to increase the accuracy of future space weather and climate models. Thirteen years of NO flux data, observed at 100-250 km altitude by the SABER instrument onboard the TIMED satellite, is decomposed into five empirical orthogonal functions (EOFs) and their amplitudes to: 1) determine the strongest modes of variability in the data set, and 2) develop a compact model of NO flux. The first five EOFs account for 85% of the variability in the data, and their uncertainty is verified using cross-validation analysis. Although these linearly independent EOFs are not necessarily independent in a geophysical sense, the first three EOFs correlate strongly with different geophysical processes. The first EOF correlates strongly with Kp and F10.7, suggesting that geomagnetic storms and solar weather account for a large portion of NO flux variability. EOF 2 shows annual variations, and EOF 3 correlates with solar wind parameters. Using these relations, an empirical model of the EOF amplitudes can be derived, which could be used as a predictive tool for future NO emissions. We illustrate the NO model, highlight some of the hemispheric asymmetries, and discuss the geophysical associations of the EOFs.

  20. Nighttime exposure to electromagnetic fields and childhood leukemia: an extended pooled analysis

    DEFF Research Database (Denmark)

    Schüz, Joachim; Svendsen, Anne Louise; Linet, Martha S

    2007-01-01

    analysis of case-control studies on ELF EMF exposure and risk of childhood leukemia to examine nighttime residential exposures. Data from four countries (Canada, Germany, the United Kingdom, and the United States) were included in the analysis, comprising 1,842 children diagnosed with leukemia and 3......,099 controls (diagnosis dates ranged from 1988 to 1996). The odds ratios for nighttime ELF EMF exposure for categories of 0.1-or=0.4 microT as compared with ... that nighttime measures are more appropriate; hence, the observed association between ELF EMF and childhood leukemia still lacks a plausible explanation....

  1. Analysis of Dextromethorphan and Dextrorphan in Skeletal Remains Following Differential Microclimate Exposure: Comparison of Acute vs. Repeated Drug Exposure.

    Science.gov (United States)

    Morrison, Lucas M; Unger, Kirk A; Watterson, James H

    2017-07-01

    Analysis of dextromethorphan (DXM) and its metabolite dextrorphan (DXT) in skeletal remains of rats following acute (ACU, 75 mg/kg, IP, n = 10) or three repeated (REP, 25 mg/kg, IP, n = 10, 40-min interval) doses of DXM is described. Following dosing and euthanasia, rats decomposed outdoors to skeleton in two different microclimate environments (n = 5 ACU and n = 5 REP at each site): Site A (shaded forest microenvironment) and Site B (rocky substrate exposed to direct sunlight, 600 m from Site A). Two drug-free rats at each site served as negative controls. Skeletal elements (vertebrae, ribs, pelvic girdles, femora, tibiae, skulls and scapulae) were recovered, pulverized and underwent methanolic microwave assisted extraction (MAE). Extracts were analyzed by GC-MS following clean-up by solid-phase extraction (SPE). Drug levels, expressed as mass-normalized response ratios and the ratios of DXT and DXM levels (RRDXT/RRDXM) were compared between drug exposures, microclimate sites, and across skeletal elements. DXM levels differed significantly (P < 0.05) between corresponding bone elements across exposure groups (5/7-site A; 4/7-site B), but no significant differences in DXT levels were observed between corresponding elements. RRDXT/RRDXM differed significantly (P < 0.05) between corresponding bone elements across exposure groups (6/7-site A; 5/7-site B). No significant differences were observed in levels of DXM, DXT or RRDXT/RRDXM between corresponding elements from either group between sites. When data from all bone elements was pooled, levels of DXM and RRDXT/RRDXM differed significantly between exposure groups at each site, while those of DXT did not. For both exposure groups, comparison of pooled data between sites showed no significant differences in levels of DXM, DXT or RRDXT/RRDXM. Different decomposition microclimates did not impede the discrimination of DXM exposure patterns from the analyses of DXM, DXT and RRDXT/RRDXM in bone samples. © The Author 2017

  2. Numerical model for atmospheric diffusion analysis and evaluation of effective dose for safety analysis

    International Nuclear Information System (INIS)

    Sada, Koichi; Michioka, Takenobu; Ichikawa, Yoichi; Komiyama, Sumito

    2009-01-01

    A numerical simulation method has been developed to predict atmospheric flow and stack gas diffusion, considering the buildings and complex terrain located near and relatively far from a stack, respectively. The turbulence closure technique was used for flow calculation, some calculation grids on the ground near a stack were treated as buildings, and stack gas diffusion was predicted using the Lagrangian particle model. The calculated flow and stack gas diffusion results were compared with those obtained by wind tunnel experiments under actual terrain containing buildings. Effective stack height was estimated by comparing the surface concentration along the plume axis with those under a flat-plate condition, and it was apparent that the effective stack heights estimated by calculations were almost the same as those obtained by the wind tunnel experiment. Then, the effective dose and relative concentration of stack gas were calculated using the effective stack heights obtained by a numerical model. Almost the same effective dose and relative concentration were obtained when compared with those using the effective stack height obtained by wind tunnel experiment. (author)

  3. Adjoint Sensitivity Analysis of Radiative Transfer Equation: Temperature and Gas Mixing Ratio Weighting Functions for Remote Sensing of Scattering Atmospheres in Thermal IR

    Science.gov (United States)

    Ustinov, E.

    1999-01-01

    Sensitivity analysis based on using of the adjoint equation of radiative transfer is applied to the case of atmospheric remote sensing in the thermal spectral region with non-negligeable atmospheric scattering.

  4. Application of PIXE analysis to study urban atmospheric aerosols from downtown Havana City

    International Nuclear Information System (INIS)

    Perez Zayas, Grizel; Pinnera Hernandez, Ibrahin; Ramos Aruca, Maridelin; Guibert Gala, Rolando; Molina Esquivel, Enrique; Martinez Varona, Miriam; Fernandez Arocha, Ariadna; Aldape Ugalde, Francisca; Flores Maldonado, Javier

    2010-01-01

    The present work reports, the results of a first study of elemental composition in airborne particulate matter (in fine and coarse particle size fractions) collected at the Atmospheric Monitoring Station in the Municipality of Centro Habana, using the Particle-Induced X-ray Emission (PIXE) technique. At present, there is not information available about elements contents in airborne particulate matter from this region. For this study, we carried out a sampling campaign during five months (November 14, 2006 to April 19, 2007). The samples were collected every second day during 24 h under an air flux of 20 l/min. The air sampler used was a Gent Sampler equipped with a Stacked Filter Unit (SFU) system which allows the aerosol collection in both size fractions simultaneously. A total of 144 aerosol samples were collected (72 correspond to the fine mass particle and 72 to the coarse mass particle). For PIXE analysis, the samples were irradiated by 2.5 MeV energy protons from the 2MV Van de Graff Tandetron Accelerator from the Laboratory of PIXE analysis at ININ, Mexico. A total of 14 elements (S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb) were consistently detected in both particle size fractions with minimum detection limits in the range of 1-10 ng/m3. The quantitative results obtained from PIXE elemental analysis for mass of particles in both fractions have revealed important information that has been used in a first attempt to understand and to characterize the atmospheric pollution of this area. A general discussion about these results is presented in this paper. (author)

  5. Application of PIXE analysis to study urban atmospheric aerosols from downtown Havana City

    International Nuclear Information System (INIS)

    Perez Zayas, Grizel; Pinnera Hernandez, Ibrahin; Ramos Aruca, Maridelin; Guibert Gala, Rolando; Molina Esquivel, Enrique; Martinez Varona, Miriam; Fernandez Arocha, Ariadna; Aldape Ugalde, Francisca; Flores Maldonado, Javier

    2009-01-01

    The present work reports, the results of a first study of elemental composition in airborne particulate matter (in fine and coarse particle size fractions) collected at the Atmospheric Monitoring Station in the Municipality of Centro Habana, using the Particle-Induced X-ray Emission (PIXE) technique. At present, there is not information available about elements contents in airborne particulate matter from this region. For this study, we carried out a sampling campaign during five months (November 14, 2006 to April 19, 2007). The samples were collected every second day during 24 h under an air flux of 20 l/min. The air sampler used was a Gent Sampler equipped with a Stacked Filter Unit (SFU) system which allows the aerosol collection in both size fractions simultaneously. A total of 144 aerosol samples were collected (72 correspond to the fine mass particle and 72 to the coarse mass particle). For PIXE analysis, the samples were irradiated by 2.5 MeV energy protons from the 2MV Van de Graff Tandetron Accelerator from the Laboratory of PIXE analysis at ININ, Mexico. A total of 14 elements (S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb) were consistently detected in both particle size fractions with minimum detection limits in the range of 1-10 ng/m3. The quantitative results obtained from PIXE elemental analysis for mass of particles in both fractions have revealed important information that has been used in a first attempt to understand and to characterize the atmospheric pollution of this area. A general discussion about these results is presented in this paper. (author)

  6. Atmosphere Processing Module Automation and Catalyst Durability Analysis for Mars ISRU Pathfinder

    Science.gov (United States)

    Petersen, Elspeth M.

    2016-01-01

    The Mars In-Situ Resource Utilization Pathfinder was designed to create fuel using components found in the planet’s atmosphere and regolith for an ascension vehicle to return a potential sample return or crew return vehicle from Mars. The Atmosphere Processing Module (APM), a subunit of the pathfinder, uses cryocoolers to isolate and collect carbon dioxide from Mars simulant gas. The carbon dioxide is fed with hydrogen into a Sabatier reactor where methane is produced. The APM is currently undergoing the final stages of testing at Kennedy Space Center prior to process integration testing with the other subunits of the pathfinder. The automation software for the APM cryocoolers was tested and found to perform nominally. The catalyst used for the Sabatier reactor was investigated to determine the factors contributing to catalyst failure. The results from the catalyst testing require further analysis, but it appears that the rapid change in temperature during reactor start up or the elevated operating temperature is responsible for the changes observed in the catalyst.

  7. Statistical-Synoptic Analysis of the Atmosphere Thickness Pattern of Iran’s Pervasive Frosts

    Directory of Open Access Journals (Sweden)

    Iman Rousta

    2016-08-01

    Full Text Available The present study aimed at analyzing the synoptic pattern of atmospheric thickness of winter pervasive frosts in Iran. To this end, the data related to the daily minimum temperature of a 50-year period (1961–2010 were gathered from 451 synoptic and climatology stations. Then, the instances in which the temperature was below 0 °C for at least two consecutive days and this phenomenon covered at least 50% of the entirety of Iran were selected. Subsequently, the atmosphere thickness pattern was extracted for these days, with the representative day being identified and analyzed through cluster analysis. The results showed that the Siberian high pressure plays a significant role in the occurrence of pervasive frosts in Iran. In some other cases, the northeast–southwest direction of this pattern leads to its combination with the East Europe high pressure, causing widespread frosts in Iran. Furthermore, the interaction between counter clockwise currents in this system and the clockwise currents in the Azores high pressure tongue directs cold weather from northern parts of Europe toward Iran. The formation of blocking systems leads to the stagnation of cold weather over Iran, a phenomenon that results in significant reduction of temperature and severe frosts in these areas. In addition, the omega pattern (the fifth pattern and Deep Eastern European trough and polar low pressure pattern (the fourth pattern were the most dominant and severe frost patterns in Iran respectively.

  8. A simplified model of the Martian atmosphere - Part 2: a POD-Galerkin analysis

    Directory of Open Access Journals (Sweden)

    S. G. Whitehouse

    2005-01-01

    Full Text Available In Part I of this study Whitehouse et al. (2005 performed a diagnostic analysis of a simplied model of the Martian atmosphere, in which topography was absent and in which heating was modelled as Newtonian relaxation towards a zonally symmetric equilibrium temperature field. There we derived a reduced-order approximation to the vertical and the horizonal structure of the baroclinically unstable Martian atmosphere, retaining only the barotropic mode and the leading order baroclinic modes. Our objectives in Part II of the study are to incorporate these approximations into a Proper Orthogonal Decomposition-Galerkin expansion of the spherical quasi-geostrophic model in order to derive hierarchies of nonlinear ordinary differential equations for the time-varying coefficients of the spatial structures. Two different vertical truncations are considered, as well as three different norms and 3 different Galerkin truncations. We investigate each in turn, using tools from bifurcation theory, to determine which of the systems most closely resembles the data for which the original diagnostics were performed.

  9. Thermogravimetric analysis of rice and wheat straw catalytic combustion in air- and oxygen-enriched atmospheres

    International Nuclear Information System (INIS)

    Yu Zhaosheng; Ma Xiaoqian; Liu Ao

    2009-01-01

    By thermogravimetric analysis (TGA) study, the influences of different catalysts on the ignition and combustion of rice and wheat straw in air- and oxygen-enriched atmospheres have been investigated in this paper. Straw combustion is divided into two stages. One is the emission and combustion of volatiles and the second is the combustion of fixed carbon. The existence of catalysts in the first step enhances the emission of volatiles from the straw. The action of catalysts in the second step of straw combustion may be as a carrier of oxygen to the fixed carbon. Two parameters have been used to compare the characteristics of ignition and combustion of straw under different catalysts and in various oxygen concentrations. One is the temperature when the conversion degree combustible (CDC) of straw is 5%, the other is the CDC when the temperature is 900 deg. C. By comparing the different values of the two parameters, the different influences of the catalysts and oxygen concentration on the ignition and combustion of straw have been studied, the action of these catalysts for straw ignition and combustion in air and oxygen-enriched atmosphere is effective except the oxygen-enriched catalytic combustion of wheat straw fixed carbon

  10. Trace element contents in atmospheric suspended particles: inferences from instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Querol, X.; Alastuey, A.; Lopez-Soler, A.; Boix, A.; Sanfeliu, T.; Martynov, V.V.; Piven, P.I.; Kabina, L.P.; Souschov, P.A.

    1997-01-01

    This study focuses on the determination of trace element concentrations in total suspended particles by instrumental neutron activation analysis (INAA) in two different areas in Northeastern Spain (a rural area influenced by the emissions of a large coal-fired power station, and the urban and industrial areas of Castellon). Total suspended particles were sampled by means of standard MCV high- and medium-volume captors, using cellulose membrane filters of 0.8 and 0.45 μm pore size. Preliminary research was performed on the homogeneous distribution of elements in the sample filters and on the study of blank filters for the calculations of the background average element contents. The results obtained allowed to distinguish different major anthropogenic sources of trace elements in the atmosphere at the sampling sites: (a) Zr, Hf, Sc, U and Th are related to atmospheric pollution derived from the ceramic industry of the Castellon area; (b) As, Cr, Cs, Rb, Sb, Se, Zn are related to traffic and other industrial emission in the Castellon area, and As, Cr, Sb and Zn to power generation emissions in the rural area. (orig.). With 3 figs., 5 tabs

  11. Rationale and Methods for Archival Sampling and Analysis of Atmospheric Trace Chemical Contaminants On Board Mir and Recommendations for the International Space Station

    Science.gov (United States)

    Perry, J. L.; James, J. T.; Cole, H. E.; Limero, T. F.; Beck, S. W.

    1997-01-01

    Collection and analysis of spacecraft cabin air samples are necessary to assess the cabin air quality with respect to crew health. Both toxicology and engineering disciplines work together to achieve an acceptably clean cabin atmosphere. Toxicology is concerned with limiting the risk to crew health from chemical sources, setting exposure limits, and analyzing air samples to determine how well these limits are met. Engineering provides the means for minimizing the contribution of the various contaminant generating sources by providing active contamination control equipment on board spacecraft and adhering to a rigorous material selection and control program during the design and construction of the spacecraft. A review of the rationale and objectives for sampling spacecraft cabin atmospheres is provided. The presently-available sampling equipment and methods are reviewed along with the analytical chemistry methods employed to determine trace contaminant concentrations. These methods are compared and assessed with respect to actual cabin air quality monitoring needs. Recommendations are presented with respect to the basic sampling program necessary to ensure an acceptably clean spacecraft cabin atmosphere. Also, rationale and recommendations for expanding the scope of the basic monitoring program are discussed.

  12. Occupational exposure and risk of chronic obstructive pulmonary disease: a systematic review and meta-analysis.

    Science.gov (United States)

    Alif, Sheikh M; Dharmage, Shyamali C; Bowatte, Gayan; Karahalios, Amalia; Benke, Geza; Dennekamp, Martine; Mehta, Amar J; Miedinger, David; Künzli, Nino; Probst-Hensch, Nicole; Matheson, Melanie C

    2016-08-01

    Due to contradictory literature we have performed a systematic review and meta-analyse of population-based studies that have used Job Exposure Matrices to assess occupational exposure and risk of Chronic Obstructive Pulmonary Disease (COPD). Two researchers independently searched databases for published articles using predefined inclusion criteria. Study quality was assessed, and results pooled for COPD and chronic bronchitis for exposure to biological dust, mineral dust, and gases/fumes using a fixed and random effect model. Five studies met predetermined inclusion criteria. The meta-analysis showed low exposure to mineral dust, and high exposure to gases/fumes were associated with an increased risk of COPD. We also found significantly increased the risk of chronic bronchitis for low and high exposure to biological dust and mineral dust. Expert commentary: The relationship between occupational exposure assessed by the JEM and the risk of COPD and chronic bronchitis shows significant association with occupational exposure. However, the heterogeneity of the meta-analyses suggests more wide population-based studies with older age groups and longitudinal phenotype assessment of COPD to clarify the role of occupational exposure to COPD risk.

  13. The multimedia models for the evaluation of exposure bond to the atmospheric emissions of classified installations; Les modeles multimedia pour l'evaluation des expositions liees aux emissions atmospheriques des installations classees

    Energy Technology Data Exchange (ETDEWEB)

    Bonnard, R

    2001-12-15

    Risk assessment and environmental impacts studies are realized to preserve the public health. Today one of the most used approach is the use of an atmospheric dispersion model to assess the risks. The data are then injected in a calculation software of exposure bond to polluted soils, to evaluate the risks of non direct exposure. This report details and evaluates the models corresponding to the need: the methodology for assessing Health Risks associated with multiple pathways of exposure to combustor, human health risk assessment proto col for hazardous waste combustion facilities, EUSES, CALTOX, MEPAS, MEND-TOX, RESRAD, MMSOILS, FRAMES-HWIR, PC-GEMS and TRIM. (A.L.B.)

  14. Meteorology in ruptured abdominal aortic aneurysm: an institutional study and a meta-analysis of published studies reporting atmospheric pressure.

    Science.gov (United States)

    Takagi, H; Watanabe, T; Mizuno, Y; Kawai, N; Umemoto, T

    2014-12-01

    The aim of this paper was to determine whether weather factors including atmospheric pressure are associated with the occurrence of ruptured abdominal aortic aneurysm (RAAA). We investigated our institutional experiences of RAAA in more than 150 patients during 8 years. Further, we performed a meta-analysis of published studies reporting the influence of atmospheric pressure on RAAA. We retrospectively evaluated 152 patients who underwent surgery for RAAA (including ruptured iliac arterial aneurysm) at our institute between 1 January 2006 and 31 December 2013. Daily regional meteorological data (in the nearest weather station located 3.5 km from the hospital) were obtained online from Japan Meteorological Agency. To identify comparative studies of mean atmospheric pressure on the day with RAAA versus that on the day without RAAA, MEDLINE and EMBASE were searched through January 2014 using Web-based search engines (PubMed and OVID). Mean sea level atmospheric pressure, delta mean atmospheric pressure (difference between mean sea level atmospheric pressure on the day and that on the previous day), and sunshine duration on the day with RAAA were significantly lower than those on the day without RAAA: 1012.43±7.44 versus 1013.71±6.49 hPa, P=0.039, -1.18±5.15 versus 0.05±5.62 hPa, P=0.005; and 4.76±3.76 versus 5.47±3.88 h, P=0.026; respectively. A pooled analysis of 8 studies (including our institutional study) demonstrated that mean atmospheric pressure on the day with RAAA was significantly lower than that on the day without RAAA: standardized mean difference, -0.09; 95% confidence interval, -0.14 to -0.04; P=0.0009. Atmospheric pressure on the day with RAAA appears lower than that on the day without RAAA. Atmospheric pressure may be associated with the occurrence of RAAA.

  15. Implementation of Coupled Skin Temperature Analysis and Bias Correction in a Global Atmospheric Data Assimilation System

    Science.gov (United States)

    Radakovich, Jon; Bosilovich, M.; Chern, Jiun-dar; daSilva, Arlindo

    2004-01-01

    The NASA/NCAR Finite Volume GCM (fvGCM) with the NCAR CLM (Community Land Model) version 2.0 was integrated into the NASA/GMAO Finite Volume Data Assimilation System (fvDAS). A new method was developed for coupled skin temperature assimilation and bias correction where the analysis increment and bias correction term is passed into the CLM2 and considered a forcing term in the solution to the energy balance. For our purposes, the fvDAS CLM2 was run at 1 deg. x 1.25 deg. horizontal resolution with 55 vertical levels. We assimilate the ISCCP-DX (30 km resolution) surface temperature product. The atmospheric analysis was performed 6-hourly, while the skin temperature analysis was performed 3-hourly. The bias correction term, which was updated at the analysis times, was added to the skin temperature tendency equation at every timestep. In this presentation, we focus on the validation of the surface energy budget at the in situ reference sites for the Coordinated Enhanced Observation Period (CEOP). We will concentrate on sites that include independent skin temperature measurements and complete energy budget observations for the month of July 2001. In addition, MODIS skin temperature will be used for validation. Several assimilations were conducted and preliminary results will be presented.

  16. Study on atmosphere pollution by PIXE analysis combining with statistical method

    International Nuclear Information System (INIS)

    Zhu Guanghua

    1994-06-01

    Atmospheric aerosol samples were collected using an 8-stage cascade impactor or an automatic time sequence step sampler at Jomo Langma, Zhangye at the edge of Gobi Desert and Beijing. Element concentration were analyzed by PIXE (proton induced X-ray emission) technique. The data were analyzed by APCA (absolute principal component analysis) to determine the principal components. The sources and contribution to the aerosol in the above three regions were discussed. The result shows that the PIXE has high sensitivity, multi-element capability, high speed and non-destruction advantages. APCA analytical method can effectively determine the aerosol components in urban area, and it also can distinguish between local components and remote components in the area far from the pollution resources

  17. Modelling dynamics of atmosphere ventilation and industrial city’s air pollution analysis: New approach

    Science.gov (United States)

    Glushkov, A. V.; Khetselius, O. Yu; Agayar, E. V.; Buyadzhi, V. V.; Romanova, A. V.; Mansarliysky, V. F.

    2017-10-01

    We present a new effective approach to analysis and modelling the natural air ventilation in an atmosphere of the industrial city, which is based on the Arakawa-Schubert and Glushkov models, modified to calculate the current involvement of the ensemble of clouds, and advanced mathematical methods of modelling an unsteady turbulence in the urban area. For the first time the methods of a plane complex field and spectral expansion algorithms are applied to calculate the air circulation for the cloud layer arrays, penetrating into the territory of the industrial city. We have also taken into account for the mechanisms of transformation of the cloud system advection over the territory of the urban area. The results of test computing the air ventilation characteristics are presented for the Odessa city. All above cited methods and models together with the standard monitoring and management systems can be considered as a basis for comprehensive “Green City” construction technology.

  18. Evaluation of atmospheric particulate concentrations derived from analysis of ratio Thematic Mapper data

    Science.gov (United States)

    Carnahan, W. H.; Mausel, P. W.; Zhou, G. P.

    1984-01-01

    An approach for atmospheric particulate concentration evaluation above urban areas using ratio Thematic Mapper (TM) data is discussed. October 25, 1982 TM data over Chicago, IL are analyzed using TM band ratios of 1/2, 1/3, 1/4, 1/5, and 1/6 and particulate concentration estimates derived from TM ratios are tested over low reflective turbid water sites and highly reflective concrete highways. From analysis of the data it is evident that for water, the pattern of increasing particulate concentration is associated with decreasing ratio values in all band combinations used. Over concrete features, the TM band 1/4 ratio values follow the predicted pattern, while the TM band 1/6 has ratios which are reversed from anticipated values.

  19. Upper limits to trace constituents in Jupiter's atmosphere from an analysis of its 5 micrometer spectrum

    Science.gov (United States)

    Treffers, R. R.; Larson, H. P.; Fink, U.; Gautier, T. N.

    1978-01-01

    A high-resolution spectrum of Jupiter at 5 micrometers recorded at the Kuiper Airborne Observatory is used to determine upper limits to the column density of 19 molecules. The upper limits to the mixing ratios of SiH4, H2S, HCN, and simple hydrocarbons are discussed with respect to current models of Jupiter's atmosphere. These upper limits are compared to expectations based upon the solar abundance of the elements. This analysis permits upper limit measurements (SiH4), or actual detections (GeH4) of molecules with mixing ratios with hydrogen as low as 10 to the minus 9th power. In future observations at 5 micrometers the sensitivity of remote spectroscopic analyses should permit the study of constituents with mixing ratios as low as 10 to the minus 10th power, which would include the hydrides of such elements as Sn and As as well as numerous organic molecules.

  20. Bromine determination by neutron activation analysis and its distribution in the atmosphere

    International Nuclear Information System (INIS)

    Iturbe Garcia, J.L.; Lopez Munoz, B.E.

    2002-01-01

    Bromine, one of the main participants in ozone layer destruction, is 10 to 100 times more effective than chlorine. There are two principal sources of methyl bromide emissions: the oceans and some pesticides that are used in farming. Bromine was detected in 'premium' and 'magna sin' gasolines (2.86±0.96 and 1.54±0.38 ppm, respectively) as well as in condensed water found in exhaust pipes of vehicles. In addition, samples of rainwater were also analyzed to determine atmospheric bromine concentration. In water samples Br concentrations ranging from 2.09 to 0.06 ppm were found. The techniques utilised were neutron activation analysis and high voltage electrophoresis, the latter to determine the chemical form of bromine in condensed water samples. Finally, suspended particles from rainwater were also analysed by scanning electron microscopy (SEM). (author)

  1. Comparative analysis of three atmospheric dispersion coefficient systems at the Angra dos Reis, RJ, region

    International Nuclear Information System (INIS)

    Biagio, Rosa Maria de Souza

    1982-01-01

    A comparative analysis was made in this work among Pasquill-Gifford (PG) atmospheric dispersion coefficients and those determined at the Juelich and Karlsruhe sites with the purpose of suggesting which one would be the most applicable to the Angra site. Each one of the three systems was determined by different experiments, carried out over sites with diversified features. The systems of Juelich and Karlsruhe were obtained over sites with high surface roughness and from stacks (elevated releases), while the PG system was obtained over sites with a small surface roughness and from ground level releases. The results of the application of these systems at a complex site like Angra,which has a highly diversified structure encompassing sea, vegetation, predominance of light winds and stable stability classes, show that the PG system, the most used in the world, is still the best choice. (author)

  2. Secondary ion mass spectrometry: The application in the analysis of atmospheric particulate matter

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Di; Hua, Xin; Xiu, Guang-Li; Zheng, Yong-Jie; Yu, Xiao-Ying; Long, Yi-Tao

    2017-10-01

    Currently, considerable attention has been paid to atmospheric particulate matter (PM) investigation due to its importance in human health and global climate change. Surface characterization of PM is important since the chemical heterogeneity between the surface and bulk may vary its impact on the environment and human being. Secondary ion mass spectrometry (SIMS) is a surface technique with high surface sensitivity, capable of high spatial chemical imaging and depth profiling. Recent research shows that SIMS holds great potential in analyzing both surface and bulk chemical information of PM. In this review, we presented the working principal of SIMS in PM characterization, summarized recent applications in PM analysis from different sources, discussed its advantages and limitations, and proposed the future development of this technique with a perspective in environmental sciences.

  3. Atmospheric forcing of decadal Baltic Sea level variability in the last 200 years. A statistical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Huenicke, B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Kuestenforschung

    2008-11-06

    This study aims at the estimation of the impact of different atmospheric factors on the past sealevel variations (up to 200 years) in the Baltic Sea by statistically analysing the relationship between Baltic Sea level records and observational and proxy-based reconstructed climatic data sets. The focus lies on the identification and possible quantification of the contribution of sealevel pressure (wind), air-temperature and precipitation to the low-frequency (decadal and multi-decadal) variability of Baltic Sea level. It is known that the wind forcing is the main factor explaining average Baltic Sea level variability at inter-annual to decadal timescales, especially in wintertime. In this thesis it is statistically estimated to what extent other regional climate factors contribute to the spatially heterogeneous Baltic Sea level variations around the isostatic trend at multi-decadal timescales. Although the statistical analysis cannot be completely conclusive, as the potential climate drivers are all statistically interrelated to some degree, the results indicate that precipitation should be taken into account as an explanatory variable for sea-level variations. On the one hand it has been detected that the amplitude of the annual cycle of Baltic Sea level has increased throughout the 20th century and precipitation seems to be the only factor among those analysed (wind through SLP field, barometric effect, temperature and precipitation) that can account for this evolution. On the other hand, precipitation increases the ability to hindcast inter-annual variations of sea level in some regions and seasons, especially in the Southern Baltic in summertime. The mechanism by which precipitation exerts its influence on Baltic Sea level is not ascertained in this statistical analysis due to the lack of long salinity time series. This result, however, represents a working hypothesis that can be confirmed or disproved by long simulations of the Baltic Sea system - ocean

  4. Atmospheric metal deposition in France: Estimation based on moss analysis. First results

    International Nuclear Information System (INIS)

    Galsomies, L.; Letrouit-Galinou, M.A.; Avnaim, M.; Duclaux, G.; Deschamps, C.; Savanne, D.

    2000-01-01

    The aim of this programme set up by University Pierre and Marie Curie-Paris VI and ADEME (French Agency for the Environment and Energy Management) is to obtain information on the atmospheric deposition of 36 elements (most being heavy metals) all over France, using 5 common mosses as bioaccumulators: Pleurozium schreberi, Hylocomium splendens, Hypnum cupressiforme, Scleropodium purum and Thuidium tamariscinum. Sampling was performed in 1996 from April to November thanks to 43 collectors. One sample of moss at least has been collected in 512 sites distributed over France, with an average density of one site each 1000 km 2 . Procedures for sampling, drying, cleaning, sorting are strictly codified based on Scandinavian guidelines. Analyses are performed according to two procedures: ICP-MS (Inductively Coupled Plasma, Mass Spectrometry) for Pb, Ni specialty and INAA (instrumental Neutron Activation Analysis for other elements. Data concerning As, Cd, Cr, Cu, Fe, Hg, Pb. Ni, V, Zn will be incorporated into the 1995-1996 European Programme 'Atmospheric Heavy Metal Deposition in Europe - estimation based on moss analysis' coordinated by the Nordic Council. The analyses are in progress, but preliminary results from Ile-de-France have been achieved for 34 elements in INAA. A preliminary study has shown that interspecies calibration could be possible for some heavy metals and that saturation effects in one species could be present when the intercalibration between species is not possible. Such a programme is made possible thanks to the financial support of the French Ministry of Environment and ADEME and with the active cooperation of several national organisations, especially the Laboratory Pierre Sue (CNRS-CEA). (author)

  5. The atmospheric parameters of FGK stars using wavelet analysis of CORALIE spectra

    Science.gov (United States)

    Gill, S.; Maxted, P. F. L.; Smalley, B.

    2018-05-01

    Context. Atmospheric properties of F-, G- and K-type stars can be measured by spectral model fitting or with the analysis of equivalent width (EW) measurements. These methods require data with good signal-to-noise ratios (S/Ns) and reliable continuum normalisation. This is particularly challenging for the spectra we have obtained with the CORALIE échelle spectrograph for FGK stars with transiting M-dwarf companions. The spectra tend to have low S/Ns, which makes it difficult to analyse them using existing methods. Aims: Our aim is to create a reliable automated spectral analysis routine to determine Teff, [Fe/H], V sini from the CORALIE spectra of FGK stars. Methods: We use wavelet decomposition to distinguish between noise, continuum trends, and stellar spectral features in the CORALIE spectra. A subset of wavelet coefficients from the target spectrum are compared to those from a grid of models in a Bayesian framework to determine the posterior probability distributions of the atmospheric parameters. Results: By testing our method using synthetic spectra we found that our method converges on the best fitting atmospheric parameters. We test the wavelet method on 20 FGK exoplanet host stars for which higher-quality data have been independently analysed using EW measurements. We find that we can determine Teff to a precision of 85 K, [Fe/H] to a precision of 0.06 dex and V sini to a precision of 1.35 km s-1 for stars with V sini ≥ 5 km s-1. We find an offset in metallicity ≈- 0.18 dex relative to the EW fitting method. We can determine log g to a precision of 0.13 dex but find systematic trends with Teff. Measurements of log g are only reliable enough to confirm dwarf-like surface gravity (log g ≈ 4.5). Conclusions: The wavelet method can be used to determine Teff, [Fe/H], and V sini for FGK stars from CORALIE échelle spectra. Measurements of log g are unreliable but can confirm dwarf-like surface gravity. We find that our method is self consistent, and

  6. Characterization of exposure to extremely low frequency magnetic fields using multidimensional analysis techniques.

    Science.gov (United States)

    Verrier, A; Souques, M; Wallet, F

    2005-05-01

    Our lack of knowledge about the biological mechanisms of 50 Hz magnetic fields makes it hard to improve exposure assessment. To provide better information about these exposure measures, we use multidimensional analysis techniques to examine the relations between different exposure metrics for a group of subjects. We used a combination of a two stage Principal Component Analysis (PCA) followed by an ascending hierarchical classification (AHC) to identify a set of measures that would capture the characteristics of the total exposure. This analysis gives an indication of the aspects of the exposure that are important to capture to get a complete picture of the magnetic field environment. We calculated 44 metrics of exposure measures from 16 exposed EDF employees and 15 control subjects, containing approximately 20,000 recordings of magnetic field measurements, taken every 30 s for 7 days with an EMDEX II dosimeter. These metrics included parameters used routinely or occasionally and some that were new. To eliminate those that expressed the least variability and that were most highly correlated to one another, we began with an initial Principal Component Analysis (PCA). A second PCA of the remaining 12 metrics enabled us to identify from the foreground 82.7% of the variance: the first component (62.0%) was characterized by central tendency metrics, and the second (20.7%) by dispersion characteristics. We were able to use AHC to divide the entire sample (of individuals) into four groups according to the axes that emerged from the PCA. Finally, discriminant analysis tested the discriminant power of the variables in the exposed/control classification as well as those from the AHC classification. The first showed that two subjects had been incorrectly classified, while no classification error was observed in the second. This exploratory study underscores the need to improve exposure measures by using at least two dimensions: intensity and dispersion. It also indicates the

  7. Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

    Science.gov (United States)

    Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

    2016-09-01

    Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship.

  8. First atmospheric diffusion experiment compaign at the Angra site. Analysis of the data measured

    International Nuclear Information System (INIS)

    Nicolli, D.

    1986-07-01

    An analysis of the data measured during the first atmospheric diffusion experiment campaign at the Angra site is presented. Some time before the diffusion experiments, with tritiated water vapor used as a tracer (HTO) could be started, many preparatory studies had to be concluded due to the local complex terrain surrounded by steep hills on three sides and a bay in the southern direction. An introductory account of these previous steps is given. Tritiated water vapor was released from a 100m-high tower and air humidity sampled at 25 locations as far as 1Km downwind of the source. An elaborated isoconcentration analysis indicates the plume spread has a Gaussian distribution in the horizontal plane up to the edge of the site's area bordered by the hill's top (about 1Km far-off). Nevertheless the Gaussian model has a restricted applicability at some parts of the site because of the terrain unevenness. In general, the results are comparable to those obtained in other countries for complex terrain. Meanwhile, the Angra's experiments seem only to validate the Gaussian model for short range dispersion from an elevated source. For releases in the lowest layer, the Gaussian model might not be valid. The isoconcentration analysis strengthens the assumption of sea breeze recirculation on the site. (Author) [pt

  9. Atmospheric pressure chemical ionization Fourier transform ion cyclotron resonance mass spectrometry for complex thiophenic mixture analysis

    KAUST Repository

    Hourani, Nadim

    2013-10-01

    Rationale Polycyclic aromatic sulfur heterocycles (PASHs) are detrimental species for refining processes in petroleum industry. Current mass spectrometric Methods that determine their composition are often preceded by derivatization and dopant addition approaches. Different ionization Methods have different impact on the molecular assignment of complex PASHs. The analysis of such species under atmospheric pressure chemical ionization (APCI) is still considered limited due to uncontrolled ion generation with low- and high-mass PASHs. Methods The ionization behavior of a model mixture of five selected PASH standards was investigated using an APCI source with nitrogen as the reagent gas. A complex thiophenic fraction was separated from a vacuum gas oil (VGO) and injected using the same method. The samples were analyzed using Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS). RESULTS PASH model analytes were successfully ionized and mainly [M + H]+ ions were produced. The same ionization pattern was observed for the real thiophenic sample. It was found that S1 class species were the major sulfur-containing species found in the VGO sample. These species indicated the presence of alkylated benzothiophenic (BT), dibenzothiophenic (DBT) and benzonaphthothiophenic (BNT) series that were detected by APCI-FTICR MS. CONCLUSIONS This study provides an established APCI-FTICR MS method for the analysis of complex PASHs. PASHs were detected without using any derivatization and without fragmentation. The method can be used for the analysis of S-containing crude oil samples. © 2013 John Wiley & Sons, Ltd.

  10. PIXE Analysis of Atmospheric Aerosol Samples Collected in the Adirondack Mountains

    Science.gov (United States)

    Yoskowitz, Josh; Ali, Salina; Nadareski, Benjamin; Safiq, Alexandrea; Smith, Jeremy; Labrake, Scott; Vineyard, Michael

    2013-10-01

    We have performed an elemental analysis of atmospheric aerosol samples collected at Piseco Lake in Upstate New York using proton induced x-ray emission spectroscopy (PIXE). This work is part of a systematic study of airborne pollution in the Adirondack Mountains. Of particular interest is the sulfur content that can contribute to acid rain, a well-documented problem in the Adirondacks. We used a nine-stage cascade impactor to collect the samples and distribute the particulate matter onto Kapton foils by particle size. The PIXE experiments were performed with 2.2-MeV proton beams from the 1.1-MV pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. X-Ray energy spectra were measured with a silicon drift detector and analyzed with GUPIX software to determine the elemental concentrations of the aerosols. A broad range of elements from silicon to zinc were detected with significant sulfur concentrations measured for particulate matter between 0.25 and 0.5 μm in size. The PIXE analysis will be described and preliminary results will be presented.

  11. Effects of minimal exposures to atmospheric pressure plasma on the activity of Salmonella Typhimurium: Deactivation of bacterial motility and suppression of host-cell invasion.

    Science.gov (United States)

    Park, Jin-Sung; Kim, Kijung; Han, Je-Hyun; Gweon, Bomi; Ko, Ung Hyun; Yoo, Suk Jae; Choe, Wonho; Shin, Jennifer H

    2016-09-01

    Atmospheric pressure plasma (APP) has been shown effective in sterilization by reducing the number of viable microbes during surface cleaning, food processing, or human tissue treatment. For safe conduct, the majority of previous research focused on complete abolition of microbes, which may require severe treatments. Our aim is to investigate the minimal treatment conditions necessary for effective inactivation of bacteria in such a manner that the APP treated bacteria would not be able to harm the host cells. For this, we ought to identify the objective criteria to make the bacteria dysfunctional. We choose the motile properties and the host-cell invasion capability as two measures to quantify the pathogenic state of bacteria. In this paper, we investigated how the APP treatment in a minimal dosage affects the activity of Salmonella Typhimurium. At 100 W and 15 kHz for 20 s, the APP treatment effectively suppressed active "run and tumble" type motility and induced formation of abnormally long structures. With 20 s exposure, the bacterial cells failed to cause pyroptosis in the host cells with >90% survival after 12 h of co-incubation. Our results suggest novel measures to evaluate the functional pathogenic state for identifying safe APP treatment conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Evaluation of atmospheric transport models for use in Phase II of the historical public exposures studies at the Rocky Flats Plant

    Energy Technology Data Exchange (ETDEWEB)

    Rood, A.S.; Killough, G.G.; Till, J.E.

    1999-08-01

    Five atmospheric transport models were evaluated for use in Phase II of the Historical Public Exposures Studies at the Rocky Flats Plant. Models included a simple straight-line Gaussian plume model (ISCST2), several integrated puff models (RATCHET, TRIAD, and INPUFF2), and a complex terrain model (TRAC). Evaluations were based on how well model predictions compared with sulfur hexafluoride tracer measurements taken in the vicinity of Rocky Flats in February 1991. Twelve separate tracer experiments were conducted, each lasting 9 hr and measured at 140 samplers in arcs 8 and 16 km from the release point at Rocky Flats. Four modeling objectives were defined based on the endpoints of the overall study: (1) the unpaired maximum hourly average concentration, (2) paired time-averaged concentration, (3) unpaired time-averaged concentration, and (4) arc-integrated concentration. Performance measures were used to evaluate models and focused on the geometric mean and standard deviation of the predicted-to-observed ratio and the correlation coefficient between predicted and observed concentrations. No one model consistently outperformed the others in all modeling objectives and performance measures. The overall performance of the RATCHET model was somewhat better than the other models.

  13. Mendelian randomization analysis of a time-varying exposure for binary disease outcomes using functional data analysis methods.

    Science.gov (United States)

    Cao, Ying; Rajan, Suja S; Wei, Peng

    2016-12-01

    A Mendelian randomization (MR) analysis is performed to analyze the causal effect of an exposure variable on a disease outcome in observational studies, by using genetic variants that affect the disease outcome only through the exposure variable. This method has recently gained popularity among epidemiologists given the success of genetic association studies. Many exposure variables of interest in epidemiological studies are time varying, for example, body mass index (BMI). Although longitudinal data have been collected in many cohort studies, current MR studies only use one measurement of a time-varying exposure variable, which cannot adequately capture the long-term time-varying information. We propose using the functional principal component analysis method to recover the underlying individual trajectory of the time-varying exposure from the sparsely and irregularly observed longitudinal data, and then conduct MR analysis using the recovered curves. We further propose two MR analysis methods. The first assumes a cumulative effect of the time-varying exposure variable on the disease risk, while the second assumes a time-varying genetic effect and employs functional regression models. We focus on statistical testing for a causal effect. Our simulation studies mimicking the real data show that the proposed functional data analysis based methods incorporating longitudinal data have substantial power gains compared to standard MR analysis using only one measurement. We used the Framingham Heart Study data to demonstrate the promising performance of the new methods as well as inconsistent results produced by the standard MR analysis that relies on a single measurement of the exposure at some arbitrary time point. © 2016 WILEY PERIODICALS, INC.

  14. Using barometric time series of the IMS infrasound network for a global analysis of thermally induced atmospheric tides

    Science.gov (United States)

    Hupe, Patrick; Ceranna, Lars; Pilger, Christoph

    2018-04-01

    The International Monitoring System (IMS) has been established to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty and comprises four technologies, one of which is infrasound. When fully established, the IMS infrasound network consists of 60 sites uniformly distributed around the globe. Besides its primary purpose of determining explosions in the atmosphere, the recorded data reveal information on other anthropogenic and natural infrasound sources. Furthermore, the almost continuous multi-year recordings of differential and absolute air pressure allow for analysing the atmospheric conditions. In this paper, spectral analysis tools are applied to derive atmospheric dynamics from barometric time series. Based on the solar atmospheric tides, a methodology for performing geographic and temporal variability analyses is presented, which is supposed to serve for upcoming studies related to atmospheric dynamics. The surplus value of using the IMS infrasound network data for such purposes is demonstrated by comparing the findings on the thermal tides with previous studies and the Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2), which represents the solar tides well in its surface pressure fields. Absolute air pressure recordings reveal geographical characteristics of atmospheric tides related to the solar day and even to the lunar day. We therefore claim the chosen methodology of using the IMS infrasound network to be applicable for global and temporal studies on specific atmospheric dynamics. Given the accuracy and high temporal resolution of the barometric data from the IMS infrasound network, interactions with gravity waves and planetary waves can be examined in future for refining the knowledge of atmospheric dynamics, e.g. the origin of tidal harmonics up to 9 cycles per day as found in the barometric data sets. Data assimilation in empirical models of solar tides would be a valuable application of the IMS infrasound

  15. Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure

    Science.gov (United States)

    2016-05-09

    rats. The exposed hair samples were received from USAMRICD early in method development and required storage until the method was developed and validated...Because the storage of hair samples after an exposure has not been studied, it was unclear as to whether the analyte would be stable in the stored...biological matrixes typically used for analysis (i.e., blood, urine , and tissues), limiting the amount of time after an exposure that verification is

  16. Exposure, hazard, and survival analysis of diffusion on social networks.

    Science.gov (United States)

    Wu, Jiacheng; Crawford, Forrest W; Kim, David A; Stafford, Derek; Christakis, Nicholas A

    2018-04-29

    Sociologists, economists, epidemiologists, and others recognize the importance of social networks in the diffusion of ideas and behaviors through human societies. To measure the flow of information on real-world networks, researchers often conduct comprehensive sociometric mapping of social links between individuals and then follow the spread of an "innovation" from reports of adoption or change in behavior over time. The innovation is introduced to a small number of individuals who may also be encouraged to spread it to their network contacts. In conjunction with the known social network, the pattern of adoptions gives researchers insight into the spread of the innovation in the population and factors associated with successful diffusion. Researchers have used widely varying statistical tools to estimate these quantities, and there is disagreement about how to analyze diffusion on fully observed networks. Here, we describe a framework for measuring features of diffusion processes on social networks using the epidemiological concepts of exposure and competing risks. Given a realization of a diffusion process on a fully observed network, we show that classical survival regression models can be adapted to estimate the rate of diffusion, and actor/edge attributes associated with successful transmission or adoption, while accounting for the topology of the social network. We illustrate these tools by applying them to a randomized network intervention trial conducted in Honduras to estimate the rate of adoption of 2 health-related interventions-multivitamins and chlorine bleach for water purification-and determine factors associated with successful social transmission. Copyright © 2018 John Wiley & Sons, Ltd.

  17. Synthetic oligomer analysis using atmospheric pressure photoionization mass spectrometry at different photon energies

    International Nuclear Information System (INIS)

    Desmazières, Bernard; Legros, Véronique; Giuliani, Alexandre; Buchmann, William

    2014-01-01

    Graphical abstract: Atmospheric pressure photoIonization mass spectra of synthetic oligomers were recorded in the negative mode by varying the photon energy using synchrotron radiation. Photon energy required for an efficient ionization of the polymer was correlated to ionization potential of the solvent (for example 9.4 eV for tetrahydrofuran). -- Highlights: •Atmospheric pressure photoionization was performed using synchrotron radiation. •Photoionization of oligomers in THF with 10% CH 2 Cl 2 produces intact [M + Cl] − ions. •The photon energy required corresponds to ionization potential of the solvent. •Polymer distributions depend on source parameters such T °C and applied voltages. •Liquid chromatography was coupled to MS using an APPI interface for polymer analysis. -- Abstract: Atmospheric pressure photoionization (APPI) followed by mass spectrometric detection was used to ionize a variety of polymers: polyethylene glycol, polymethyl methacrylate, polystyrene, and polysiloxane. In most cases, whatever the polymer or the solvent used (dichloromethane, tetrahydrofuran, hexane, acetone or toluene), only negative ion mode produced intact ions such as chlorinated adducts, with no or few fragmentations, in contrast to the positive ion mode that frequently led to important in-source fragmentations. In addition, it was shown that optimal detection of polymer distributions require a fine tuning of other source parameters such as temperature and ion transfer voltage. Series of mass spectra were recorded in the negative mode, in various solvents (dichloromethane, tetrahydrofuran, hexane, toluene, and acetone), by varying the photon energy from 8 eV up to 10.6 eV using synchrotron radiation. To these solvents, addition of a classical APPI dopant (toluene or acetone) was not necessary. Courtesy of the synchrotron radiation, it was demonstrated that the photon energy required for an efficient ionization of the polymer was correlated to the ionization energy

  18. Synthetic oligomer analysis using atmospheric pressure photoionization mass spectrometry at different photon energies

    Energy Technology Data Exchange (ETDEWEB)

    Desmazières, Bernard [Global Bioenergies, 5 rue Henri Desbruyeres, 91030 Evry (France); Legros, Véronique [CNRS, UMR8587, Université d’Evry-Val-d’Essonne, Laboratoire Analyse et Modélisation pour la Biologie et l’Environnement, F-91025 Evry (France); Giuliani, Alexandre [Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin, 91192 Gif-sur-Yvette (France); UAR1008, CEPIA, INRA, Rue de la Geraudiere, F-44316 Nantes (France); Buchmann, William, E-mail: william.buchmann@univ-evry.fr [CNRS, UMR8587, Université d’Evry-Val-d’Essonne, Laboratoire Analyse et Modélisation pour la Biologie et l’Environnement, F-91025 Evry (France)

    2014-01-15

    Graphical abstract: Atmospheric pressure photoIonization mass spectra of synthetic oligomers were recorded in the negative mode by varying the photon energy using synchrotron radiation. Photon energy required for an efficient ionization of the polymer was correlated to ionization potential of the solvent (for example 9.4 eV for tetrahydrofuran). -- Highlights: •Atmospheric pressure photoionization was performed using synchrotron radiation. •Photoionization of oligomers in THF with 10% CH{sub 2}Cl{sub 2} produces intact [M + Cl]{sup −} ions. •The photon energy required corresponds to ionization potential of the solvent. •Polymer distributions depend on source parameters such T °C and applied voltages. •Liquid chromatography was coupled to MS using an APPI interface for polymer analysis. -- Abstract: Atmospheric pressure photoionization (APPI) followed by mass spectrometric detection was used to ionize a variety of polymers: polyethylene glycol, polymethyl methacrylate, polystyrene, and polysiloxane. In most cases, whatever the polymer or the solvent used (dichloromethane, tetrahydrofuran, hexane, acetone or toluene), only negative ion mode produced intact ions such as chlorinated adducts, with no or few fragmentations, in contrast to the positive ion mode that frequently led to important in-source fragmentations. In addition, it was shown that optimal detection of polymer distributions require a fine tuning of other source parameters such as temperature and ion transfer voltage. Series of mass spectra were recorded in the negative mode, in various solvents (dichloromethane, tetrahydrofuran, hexane, toluene, and acetone), by varying the photon energy from 8 eV up to 10.6 eV using synchrotron radiation. To these solvents, addition of a classical APPI dopant (toluene or acetone) was not necessary. Courtesy of the synchrotron radiation, it was demonstrated that the photon energy required for an efficient ionization of the polymer was correlated to the

  19. Facial image analysis to detect gestational alcohol exposure

    African Journals Online (AJOL)

    of structural anomalies and neurocognitive and behavioural disabilities, known as ... A simple, cost-effective method for large-scale FAS and FASD screening ... may be introduced to address the learning needs of affected children. ... early interventions for children with FAS. .... with FAS.15 Landmark-based shape analysis.

  20. Spectral analysis of atmospheric composition: application to surface ozone model–measurement comparisons

    Directory of Open Access Journals (Sweden)

    D. R. Bowdalo

    2016-07-01

    Full Text Available Models of atmospheric composition play an essential role in our scientific understanding of atmospheric processes and in providing policy strategies to deal with societally relevant problems such as climate change, air quality, and ecosystem degradation. The fidelity of these models needs to be assessed against observations to ensure that errors in model formulations are found and that model limitations are understood. A range of approaches are necessary for these comparisons. Here, we apply a spectral analysis methodology for this comparison. We use the Lomb–Scargle periodogram, a method similar to a Fourier transform, but better suited to deal with the gapped data sets typical of observational data. We apply this methodology to long-term hourly ozone observations and the equivalent model (GEOS-Chem output. We show that the spectrally transformed observational data show a distinct power spectrum with regimes indicative of meteorological processes (weather, macroweather and specific peaks observed at the daily and annual timescales together with corresponding harmonic peaks at one-half, one-third, etc., of these frequencies. Model output shows corresponding features. A comparison between the amplitude and phase of these peaks introduces a new comparison methodology between model and measurements. We focus on the amplitude and phase of diurnal and seasonal cycles and present observational/model comparisons and discuss model performance. We find large biases notably for the seasonal cycle in the mid-latitude Northern Hemisphere where the amplitudes are generally overestimated by up to 16 ppbv, and phases are too late on the order of 1–5 months. This spectral methodology can be applied to a range of model–measurement applications and is highly suitable for Multimodel Intercomparison Projects (MIPs.

  1. Statistical Methods and Software for the Analysis of Occupational Exposure Data with Non-detectable Values

    Energy Technology Data Exchange (ETDEWEB)

    Frome, EL

    2005-09-20

    Environmental exposure measurements are, in general, positive and may be subject to left censoring; i.e,. the measured value is less than a ''detection limit''. In occupational monitoring, strategies for assessing workplace exposures typically focus on the mean exposure level or the probability that any measurement exceeds a limit. Parametric methods used to determine acceptable levels of exposure, are often based on a two parameter lognormal distribution. The mean exposure level, an upper percentile, and the exceedance fraction are used to characterize exposure levels, and confidence limits are used to describe the uncertainty in these estimates. Statistical methods for random samples (without non-detects) from the lognormal distribution are well known for each of these situations. In this report, methods for estimating these quantities based on the maximum likelihood method for randomly left censored lognormal data are described and graphical methods are used to evaluate the lognormal assumption. If the lognormal model is in doubt and an alternative distribution for the exposure profile of a similar exposure group is not available, then nonparametric methods for left censored data are used. The mean exposure level, along with the upper confidence limit, is obtained using the product limit estimate, and the upper confidence limit on an upper percentile (i.e., the upper tolerance limit) is obtained using a nonparametric approach. All of these methods are well known but computational complexity has limited their use in routine data analysis with left censored data. The recent development of the R environment for statistical data analysis and graphics has greatly enhanced the availability of high-quality nonproprietary (open source) software that serves as the basis for implementing the methods in this paper.

  2. A comparative analysis of exposure doses between the radiation workers in dental and general hospital

    International Nuclear Information System (INIS)

    Yang, Nam Hee; Chung, Woon Kwan; Dong, Kyung Rae; Ju, Yong Jin; Song, Ha Jin; Choi, Eun Jin

    2015-01-01

    Research and investigation is required for the exposure dose of radiation workers to work in the dental hospital as increasing interest in exposure dose of the dental hospital recently accordingly, study aim to minimize radiation exposure by making a follow-up study of individual exposure doses of radiation workers, analyzing the status on individual radiation exposure management, prediction the radiation disability risk levels by radiation, and alerting the workers to the danger of radiation exposure. Especially given the changes in the dental hospital radiation safety awareness conducted the study in order to minimize radiation exposure. This study performed analyses by a comparison between general and dental hospital, comparing each occupation, with the 116,220 exposure dose data by quarter and year of 5,811 subjects at general and dental hospital across South Korea from January 1, 2008 through December 31, 2012. The following are the results obtained by analyzing average values year and quarter. In term of hospital, average doses were significantly higher in general hospitals than detal ones. In terms of job, average doses were higher in radiological technologists the other workers. Especially, they showed statistically significant differences between radiological technologists than dentists. The above-mentioned results indicate that radiation workers were exposed to radiation for the past 5 years to the extent not exceeding the dose limit (maximum 50 mSv y -1 ). The limitation of this study is that radiation workers before 2008 were excluded from the study. Objective evaluation standards did not apply to the work circumstance or condition of each hospital. Therefore, it is deemed necessary to work out analysis criteria that will be used as objective evaluation standard. It will be necessary to study radiation exposure in more precise ways on the basis of objective analysis standard in the future. Should try to minimize the radiation individual dose of

  3. A comparative analysis of exposure doses between the radiation workers in dental and general hospital

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Nam Hee; Chung, Woon Kwan; Dong, Kyung Rae; Ju, Yong Jin; Song, Ha Jin [Dept. of Nuclear Engineering, Chosun University, Gwangju (Korea, Republic of); Choi, Eun Jin [Dept. of Public Health and Medicine, Dongshin University, Naju (Korea, Republic of)

    2015-02-15

    Research and investigation is required for the exposure dose of radiation workers to work in the dental hospital as increasing interest in exposure dose of the dental hospital recently accordingly, study aim to minimize radiation exposure by making a follow-up study of individual exposure doses of radiation workers, analyzing the status on individual radiation exposure management, prediction the radiation disability risk levels by radiation, and alerting the workers to the danger of radiation exposure. Especially given the changes in the dental hospital radiation safety awareness conducted the study in order to minimize radiation exposure. This study performed analyses by a comparison between general and dental hospital, comparing each occupation, with the 116,220 exposure dose data by quarter and year of 5,811 subjects at general and dental hospital across South Korea from January 1, 2008 through December 31, 2012. The following are the results obtained by analyzing average values year and quarter. In term of hospital, average doses were significantly higher in general hospitals than detal ones. In terms of job, average doses were higher in radiological technologists the other workers. Especially, they showed statistically significant differences between radiological technologists than dentists. The above-mentioned results indicate that radiation workers were exposed to radiation for the past 5 years to the extent not exceeding the dose limit (maximum 50 mSv y{sup -1}). The limitation of this study is that radiation workers before 2008 were excluded from the study. Objective evaluation standards did not apply to the work circumstance or condition of each hospital. Therefore, it is deemed necessary to work out analysis criteria that will be used as objective evaluation standard. It will be necessary to study radiation exposure in more precise ways on the basis of objective analysis standard in the future. Should try to minimize the radiation individual dose of

  4. Time sequence analysis of flickering auroras. I - Application of Fourier analysis. [in atmosphere

    Science.gov (United States)

    Berkey, F. T.; Silevitch, M. B.; Parsons, N. R.

    1980-01-01

    Using a technique that enables one to digitize the brightness of auroral displays from individual fields of a video signal, we have analyzed the frequency content of flickering aurora. Through the application of Fourier analysis to our data, we have found that flickering aurora contains a wide range of enhanced frequencies, although the dominant frequency enhancement generally occurs in the range 6-12 Hz. Each incidence of flickering that we observed was associated with increased radio wave absorption. Furthermore, we have found that flickering occurs in bright auroral surges, the occurrence of which is not limited to the 'breakup' phase of auroral substorms. Our results are interpreted in terms of a recently proposed theory of fluctuating double layers that accounts for a number of the observational features.

  5. Probabilistic siting analysis of nuclear power plants emphasizing atmospheric dispersion of radioactive releases and radiation-induced health effects

    International Nuclear Information System (INIS)

    Savolainen, Ilkka

    1980-01-01

    A presentation is made of probabilistic evaluation schemes for nuclear power plant siting. Effects on health attributable to ionizing radiation are reviewed, for the purpose of assessment of the numbers of the most important health effect cases in light-water reactor accidents. The atmospheric dispersion of radioactive releases from nuclear power plants is discussed, and there is presented an environmental consequence assessment model in which the radioactive releases and atmospheric dispersion of the releases are treated by the application of probabilistic methods. In the model, the environmental effects arising from exposure to radiation are expressed as cumulative probability distributions and expectation values. The probabilistic environmental consequence assessment model has been applied to nuclear power plant site evaluation, including risk-benefit and cost-benefit analyses, and the comparison of various alternative sites. (author)

  6. Extractive Atmospheric Pressure Photoionization (EAPPI) Mass Spectrometry: Rapid Analysis of Chemicals in Complex Matrices.

    Science.gov (United States)

    Liu, Chengyuan; Yang, Jiuzhong; Wang, Jian; Hu, Yonghua; Zhao, Wan; Zhou, Zhongyue; Qi, Fei; Pan, Yang

    2016-10-01

    Extractive atmospheric pressure photoionization (EAPPI) mass spectrometry was designed for rapid qualitative and quantitative analysis of chemicals in complex matrices. In this method, an ultrasonic nebulization system was applied to sample extraction, nebulization, and vaporization. Mixed with a gaseous dopant, vaporized analytes were ionized through ambient photon-induced ion-molecule reactions, and were mass-analyzed by a high resolution time-of-flight mass spectrometer (TOF-MS). After careful optimization and testing with pure sample solution, EAPPI was successfully applied to the fast screening of capsules, soil, natural products, and viscous compounds. Analysis was completed within a few seconds without the need for preseparation. Moreover, the quantification capability of EAPPI for matrices was evaluated by analyzing six polycyclic aromatic hydrocarbons (PAHs) in soil. The correlation coefficients (R (2) ) for standard curves of all six PAHs were above 0.99, and the detection limits were in the range of 0.16-0.34 ng/mg. In addition, EAPPI could also be used to monitor organic chemical reactions in real time. Graphical Abstract ᅟ.

  7. Analysis of uncertainties caused by the atmospheric dispersion model in accident consequence assessments with UFOMOD

    International Nuclear Information System (INIS)

    Fischer, F.; Ehrhardt, J.

    1988-06-01

    Various techniques available for uncertainty analysis of large computer models are applied, described and selected as most appropriate for analyzing the uncertainty in the predictions of accident consequence assessments. The investigation refers to the atmospheric dispersion and deposition submodel (straight-line Gaussian plume model) of UFOMOD, whose most important input variables and parameters are linked with probability distributions derived from expert judgement. Uncertainty bands show how much variability exists, sensitivity measures determine what causes this variability in consequences. Results are presented as confidence bounds of complementary cumulative frequency distributions (CCFDs) of activity concentrations, organ doses and health effects, partially as a function of distance from the site. In addition the ranked influence of the uncertain parameters on the different consequence types is shown. For the estimation of confidence bounds it was sufficient to choose a model parameter sample size of n (n=59) equal to 1.5 times the number of uncertain model parameters. Different samples or an increase of sample size did not change the 5%-95% - confidence bands. To get statistically stable results of the sensitivity analysis, larger sample sizes are needed (n=100, 200). Random or Latin-hypercube sampling schemes as tools for uncertainty and sensitivity analyses led to comparable results. (orig.) [de

  8. Temporal analysis of laser beam propagation in the atmosphere using computer-generated long phase screens.

    Science.gov (United States)

    Dios, Federico; Recolons, Jaume; Rodríguez, Alejandro; Batet, Oscar

    2008-02-04

    Temporal analysis of the irradiance at the detector plane is intended as the first step in the study of the mean fade time in a free optical communication system. In the present work this analysis has been performed for a Gaussian laser beam propagating in the atmospheric turbulence by means of computer simulation. To this end, we have adapted a previously known numerical method to the generation of long phase screens. The screens are displaced in a transverse direction as the wave is propagated, in order to simulate the wind effect. The amplitude of the temporal covariance and its power spectrum have been obtained at the optical axis, at the beam centroid and at a certain distance from these two points. Results have been worked out for weak, moderate and strong turbulence regimes and when possible they have been compared with theoretical models. These results show a significant contribution of beam wander to the temporal behaviour of the irradiance, even in the case of weak turbulence. We have also found that the spectral bandwidth of the covariance is hardly dependent on the Rytov variance.

  9. Economic analysis of atmospheric mercury emission control for coal-fired power plants in China.

    Science.gov (United States)

    Ancora, Maria Pia; Zhang, Lei; Wang, Shuxiao; Schreifels, Jeremy; Hao, Jiming

    2015-07-01

    Coal combustion and mercury pollution are closely linked, and this relationship is particularly relevant in China, the world's largest coal consumer. This paper begins with a summary of recent China-specific studies on mercury removal by air pollution control technologies and then provides an economic analysis of mercury abatement from these emission control technologies at coal-fired power plants in China. This includes a cost-effectiveness analysis at the enterprise and sector level in China using 2010 as a baseline and projecting out to 2020 and 2030. Of the control technologies evaluated, the most cost-effective is a fabric filter installed upstream of the wet flue gas desulfurization system (FF+WFGD). Halogen injection (HI) is also a cost-effective mercury-specific control strategy, although it has not yet reached commercial maturity. The sector-level analysis shows that 193 tons of mercury was removed in 2010 in China's coal-fired power sector, with annualized mercury emission control costs of 2.7 billion Chinese Yuan. Under a projected 2030 Emission Control (EC) scenario with stringent mercury limits compared to Business As Usual (BAU) scenario, the increase of selective catalytic reduction systems (SCR) and the use of HI could contribute to 39 tons of mercury removal at a cost of 3.8 billion CNY. The economic analysis presented in this paper offers insights on air pollution control technologies and practices for enhancing atmospheric mercury control that can aid decision-making in policy design and private-sector investments. Copyright © 2015. Published by Elsevier B.V.

  10. High-molecular products analysis of VOC destruction in atmospheric pressure discharge

    International Nuclear Information System (INIS)

    Grossmannova, Hana; Ciganek, Miroslav; Krcma, Frantisek

    2007-01-01

    We investigate the issue of applicability of the solid phase microextraction (SPME) in the analysis of volatile organic compounds (VOCs) destruction products in the gliding arc discharge. Our research is focused on the measurements with the simple one stage gliding arc reactor, applied voltage was varied in the range of 3.5-4 kV. As a carrier gas, the dry air and its mixtures with nitrogen and oxygen, enriched by toluene, with flow rate of 1000-3500 ml/min was used. Total decomposition of toluene of 97 % was achieved at the oxygen content in carrier gas of 60 %. For measurements with air as a carrier gas, the highest efficiency was 95 %. We also tested the SPME technique suitability for the quantitative analysis of exhausts gases and if this technique can be used efficiently in the field to extract byproducts. Carbowax/divinylbenzene and Carboxen/polydimethylsiloxane/divinylbenzene fibres were chosen for sampling. Tens of various high-molecular substances were observed, especially a large number of oxygenous compounds and further several nitrogenous and C x H y compounds. The concentrations of various generated compounds strongly depend on the oxygen content in gas mixture composition. The results showed that the fiber coated by Carbowax/divinylbenzene can extract more products independently on the used VOC compound. The Carboxen/polydimethylsiloxane/divinylbenzene fiber is useful for the analysis of oxygenous compounds and its use will be recommended especially when the destruction is done in the oxygen rich atmosphere. With the higher ratio of oxygen in the carrier gas a distinctive decline of C x H y compounds amount have been observed. We also tried to describe the significant production of some compounds like benzyl alcohol, benzeneacetaldehyde, even in oxygen content is proximate 0 %. Experimental data demonstrated that it is necessary to use several SPME fibres for full-scale high-molecular products analysis

  11. Assessing population exposure for landslide risk analysis using dasymetric cartography

    Science.gov (United States)

    Garcia, Ricardo A. C.; Oliveira, Sergio C.; Zezere, Jose L.

    2015-04-01

    Exposed Population is a major topic that needs to be taken into account in a full landslide risk analysis. Usually, risk analysis is based on an accounting of inhabitants number or inhabitants density, applied over statistical or administrative terrain units, such as NUTS or parishes. However, this kind of approach may skew the obtained results underestimating the importance of population, mainly in territorial units with predominance of rural occupation. Furthermore, the landslide susceptibility scores calculated for each terrain unit are frequently more detailed and accurate than the location of the exposed population inside each territorial unit based on Census data. These drawbacks are not the ideal setting when landslide risk analysis is performed for urban management and emergency planning. Dasymetric cartography, which uses a parameter or set of parameters to restrict the spatial distribution of a particular phenomenon, is a methodology that may help to enhance the resolution of Census data and therefore to give a more realistic representation of the population distribution. Therefore, this work aims to map and to compare the population distribution based on a traditional approach (population per administrative terrain units) and based on dasymetric cartography (population by building). The study is developed in the Region North of Lisbon using 2011 population data and following three main steps: i) the landslide susceptibility assessment based on statistical models independently validated; ii) the evaluation of population distribution (absolute and density) for different administrative territorial units (Parishes and BGRI - the basic statistical unit in the Portuguese Census); and iii) the dasymetric population's cartography based on building areal weighting. Preliminary results show that in sparsely populated administrative units, population density differs more than two times depending on the application of the traditional approach or the dasymetric

  12. [Role of biometric analysis in the retrospective assessment of exposure to asbestos].

    Science.gov (United States)

    Pairon, J C; Dumortier, P

    1999-12-01

    Despite intrinsic limitations due to differences in the bio-persistence of the various asbestos types, in the definition of control populations and in analytical techniques used by the laboratories, mineralogical analysis of biological samples is useful in the assessment of past exposure to asbestos. It provides additional information to occupational and environmental questionnaires, particularly when exposure to asbestos is doubtful, unknown or forgotten by a subject. Results should be interpreted taking into account clinical information. A positive result does not mean existence of asbestos-related disease. A negative result does not exclude previous significant asbestos exposure, clearly identified by an occupational questionnaire (particularly for exposure to chrysotile). Threshold values indicative of a high probability of previous asbestos exposure have been established for bronchoalveolar lavage fluid (BALF) samples and lung tissue samples. Quantification of asbestos bodies by light microscopy is easy to perform. Sensitivity and specificity of this analysis towards the total pulmonary asbestos fiber burden is good. Therefore this analysis should be performed first. Mineralogical analysis in BALF or lung tissue should be considered only when sampling is supported by diagnostic or therapeutic implications.

  13. Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression

    Science.gov (United States)

    Cai, Xianlei; Wang, Chen; Yu, Wanqi; Fan, Wenjie; Wang, Shan; Shen, Ning; Wu, Pengcheng; Li, Xiuyang; Wang, Fudi

    2016-01-01

    The objective of this study was to investigate the associations between selenium exposure and cancer risk. We identified 69 studies and applied meta-analysis, meta-regression and dose-response analysis to obtain available evidence. The results indicated that high selenium exposure had a protective effect on cancer risk (pooled OR = 0.78; 95%CI: 0.73–0.83). The results of linear and nonlinear dose-response analysis indicated that high serum/plasma selenium and toenail selenium had the efficacy on cancer prevention. However, we did not find a protective efficacy of selenium supplement. High selenium exposure may have different effects on specific types of cancer. It decreased the risk of breast cancer, lung cancer, esophageal cancer, gastric cancer, and prostate cancer, but it was not associated with colorectal cancer, bladder cancer, and skin cancer. PMID:26786590

  14. Exposure to teachers smoking and adolescent smoking behaviour: analysis of cross sectional data from Denmark

    DEFF Research Database (Denmark)

    Poulsen, Lis Hentze; Osler, M; Roberts, C

    2002-01-01

    OBJECTIVE: To determine whether adolescent smoking behaviour is associated with their perceived exposure to teachers or other pupils smoking at school, after adjustment for exposure to smoking at home, in school, and best friends smoking. DESIGN: Logistic regression analysis of cross sectional data...... from students in Denmark. SUBJECTS: 1515 grade 9 students (mean age 15.8) from 90 classes in 48 Danish schools. Outcome measure: Self reported smoking behaviour; daily smoking and heavy smoking, defined as those smoking more than 20 cigarettes per week. RESULTS: Of the students in this study, 62...... that they had seen other students smoking outdoors on the school premises. Adolescents' perceived exposure to teachers smoking outdoors on the school premises was significantly associated with daily smoking, having adjusted for sex, exposure to teachers smoking indoors at school and pupils smoking outdoors...

  15. Processes analysis of ocean-atmosphere interaction in Colombian marine areas

    International Nuclear Information System (INIS)

    Melo, Jeimmy; Pabon Caicedo, Jose Daniel

    2002-01-01

    This document shows the importance to understanding the processes of interaction ocean-atmosphere by means of the knowledge of the behavior of the physical and biological processes in the Colombian marine areas. For such aim, it was studied the production of the pigment concentration (chlorophyll-a) by means the state of the sea surface temperature and the atmospheric dynamics for year 2001

  16. Atmospheric Pressure-Thermal Desorption (AP-TD)/Electrospray Ionization-Mass Spectrometry for the Rapid Analysis of Bacillus Spores

    Science.gov (United States)

    A technique is described where an atmospheric pressure-thermal desorption (AP-TD) device and electrospray ionization (ESI)-mass spectrometry are coupled and used for the rapid analysis of Bacillus spores in complex matrices. The resulting AP-TD/ESI-MS technique combines the generation of volatile co...

  17. Carbon dioxide Information Analysis Center and World Data Center: A for Atmospheric trace gases. Annual progress report, FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    Burtis, M.D. [comp.] [Tennessee Univ., Knoxville, TN (United States). Energy, Environment and Resources Center; Cushman, R.M.; Boden, T.A.; Jones, S.B.; Nelson, T.R.; Stoss, F.W. [Oak Ridge National Lab., TN (United States)

    1995-03-01

    This report summarizes the activities and accomplishments made by the Carbon Dioxide Information Analysis Center and World Data Center-A for Atmospheric Trace Gases during the fiscal year 1994. Topics discussed in this report include; organization and staff, user services, systems, communications, Collaborative efforts with China, networking, ocean data and activities of the World Data Center-A.

  18. Estimate of the largest Lyapunov characteristic exponent of a high dimensional atmospheric global circulation model: a sensitivity analysis

    International Nuclear Information System (INIS)

    Guerrieri, A.

    2009-01-01

    In this report the largest Lyapunov characteristic exponent of a high dimensional atmospheric global circulation model of intermediate complexity has been estimated numerically. A sensitivity analysis has been carried out by varying the equator-to-pole temperature difference, the space resolution and the value of some parameters employed by the model. Chaotic and non-chaotic regimes of circulation have been found. [it

  19. Atmospheric deposition of trace elements in Norway studied by means of moss analysis

    International Nuclear Information System (INIS)

    Steinnes, E.

    1977-02-01

    The atmospheric deposition of 28 elements in different parts of Norway was studied by means of moss analysis. The species Hylocomium splendens was selected after a comparison of different species. For several elements large regional differences were found. The highest concentration of these elements were found in the southernmost part of the country and in places near the west coast with high annual precipitation. The lowest values were found in places with low annual precipitation in Eastern Norway and the interior parts of the more northerly parts of the country. Within each region the highest deposition was observed in places with high annual precipitation. For the elements Pb, Sb, As, and Se the observed concentration range amounted to a factor of about 20. In the case of Ag, Cd, Cs, and V the range was smaller, but still amounting to a factor of 10 or more. A lower but still distinct spread was observed for Cr, Mo, Cu, and Zn. For all these elements long distance transport from sources in the densely populated and heavily industrialized parts of Europe probably are of importance for the obsreved distribution. (Auth.)

  20. Analysis of Atmospheric Mercury and Associated Trace Gases in Dallas Fort Worth, TX (Barnett Shale area)

    Science.gov (United States)

    Laine, P. L.; Talbot, R. W.; Lefer, B. L.; Flynn, J. H.

    2012-12-01

    Throughout the month of June 2011, a variety of air quality measurements were obtained in the Dallas Fort Worth (Barnett Shale) field campaign. Species such as Hg0, O3, CO, NO, NO2, SO2 were monitored continuously along with a variety of volatile organic carbon (VOC) species ranging in size from C2 (ethane) to C9 aromatics to sesquiterpines. Mixed layer boundary heights were also monitored by Ceilometer measurements. At first glance, the mercury data has peaks that reach as high as 750 ppqv (parts per quadrillion by volume) which is approximately a 5 fold increase over the typical background values observed (~ 150 ppqv). The Fort Worth area has underlying Barnett Shale with thousands of natural gas compressor stations scattered throughout the surrounding landscape. We believe that a potential source of the elevated Hg0 is the result of leakage from these stations under the nocturnal boundary layer. A closer look at diurnal variations and backward wind trajectories will yield information pertaining to the types of air masses spanning the area. We will utilize the suite of chemical and meteorological measurements conducted during the campaign to facilitate source identification for specific time periods. Analysis of these data should provide new information on as yet unexplored sources of atmospheric mercury.

  1. Atmospheric deposition study in the area of Kardzhali lead-zinc plant based on moss analysis

    International Nuclear Information System (INIS)

    Hristozova, G.; Marinova, S.; Strelkova, L.P.; Goryajnova, Z.; Frontas'eva, M.V.; Stafilov, T.

    2015-01-01

    For the first time the moss biomonitoring technique was used to assess the environmental situation in the area affected by the lead-zinc plant as one of the most hazardous enterprises in Bulgaria. 77 Hypnum cupressiforme moss samples were collected in the Kardzhali municipality in the summer and autumn of 2011. The concentrations of a total of 47 elements were determined by means of instrumental epithermal neutron activation analysis (ENAA), atomic absorption spectrometry (AAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Multivariate statistics was applied to characterize the sources of elements detected in the samples. Four groups of elements were found. In comparison to the data averaged for the area outside of the town, the atmospheric deposition loads for the elements of industrial origin in Kardzhali, where the smelter chimney is located, were found to be much higher. Median levels of the measured concentrations of the most toxic metals (Pb, Zn, Cd, As, Cu, In, Sb) were extremely high in this hot spot when compared to the median Bulgarian cross-country data from the 2010-2011 European moss survey. GIS technology was used to produce element distribution maps illustrating deposition patterns of element pollutants in the study area. The results obtained contribute to the Bulgarian environmental research used to study and control the manufacturing processes of the lead-zinc plant in the town of Kardzhali.

  2. Emulation and Sobol' sensitivity analysis of an atmospheric dispersion model applied to the Fukushima nuclear accident

    Science.gov (United States)

    Girard, Sylvain; Mallet, Vivien; Korsakissok, Irène; Mathieu, Anne

    2016-04-01

    Simulations of the atmospheric dispersion of radionuclides involve large uncertainties originating from the limited knowledge of meteorological input data, composition, amount and timing of emissions, and some model parameters. The estimation of these uncertainties is an essential complement to modeling for decision making in case of an accidental release. We have studied the relative influence of a set of uncertain inputs on several outputs from the Eulerian model Polyphemus/Polair3D on the Fukushima case. We chose to use the variance-based sensitivity analysis method of Sobol'. This method requires a large number of model evaluations which was not achievable directly due to the high computational cost of Polyphemus/Polair3D. To circumvent this issue, we built a mathematical approximation of the model using Gaussian process emulation. We observed that aggregated outputs are mainly driven by the amount of emitted radionuclides, while local outputs are mostly sensitive to wind perturbations. The release height is notably influential, but only in the vicinity of the source. Finally, averaging either spatially or temporally tends to cancel out interactions between uncertain inputs.

  3. Inverse modelling of atmospheric tracers: non-Gaussian methods and second-order sensitivity analysis

    Directory of Open Access Journals (Sweden)

    M. Bocquet

    2008-02-01

    Full Text Available For a start, recent techniques devoted to the reconstruction of sources of an atmospheric tracer at continental scale are introduced. A first method is based on the principle of maximum entropy on the mean and is briefly reviewed here. A second approach, which has not been applied in this field yet, is based on an exact Bayesian approach, through a maximum a posteriori estimator. The methods share common grounds, and both perform equally well in practice. When specific prior hypotheses on the sources are taken into account such as positivity, or boundedness, both methods lead to purposefully devised cost-functions. These cost-functions are not necessarily quadratic because the underlying assumptions are not Gaussian. As a consequence, several mathematical tools developed in data assimilation on the basis of quadratic cost-functions in order to establish a posteriori analysis, need to be extended to this non-Gaussian framework. Concomitantly, the second-order sensitivity analysis needs to be adapted, as well as the computations of the averaging kernels of the source and the errors obtained in the reconstruction. All of these developments are applied to a real case of tracer dispersion: the European Tracer Experiment [ETEX]. Comparisons are made between a least squares cost function (similar to the so-called 4D-Var approach and a cost-function which is not based on Gaussian hypotheses. Besides, the information content of the observations which is used in the reconstruction is computed and studied on the application case. A connection with the degrees of freedom for signal is also established. As a by-product of these methodological developments, conclusions are drawn on the information content of the ETEX dataset as seen from the inverse modelling point of view.

  4. Composition and structure of the martian upper atmosphere: analysis of results from viking.

    Science.gov (United States)

    McElroy, M B; Kong, T Y; Yung, Y L; Nier, A O

    1976-12-11

    Densities for carbon dioxide measured by the upper atmospheric mass spectrometers on Viking 1 and Viking 2 are analyzed to yield height profiles for the temperature of the martian atmosphere between 120 and 200 kilometers. Densities for nitrogen and argon are used to derive vertical profiles for the eddy diffusion coefficient over the same height range. The upper atmosphere of Mars is surprisingly cold with average temperatures for both Viking 1 and Viking 2 of less than 200 degrees K, and there is significant vertical structure. Model calculations are presented and shown to be in good agreement with measured concentrations of carbon monoxide, oxygen, and nitric oxide.

  5. Direct atmospheric pressure chemical ionization-tandem mass spectrometry for the continuous real-time trace analysis of benzene, toluene, ethylbenzene, and xylenes in ambient air.

    Science.gov (United States)

    Badjagbo, Koffi; Picard, Pierre; Moore, Serge; Sauvé, Sébastien

    2009-05-01

    Real-time monitoring of benzene, toluene, ethylbenzene, and xylenes (BTEX) in ambient air is essential for the early warning detection associated with the release of these hazardous chemicals and in estimating the potential exposure risks to humans and the environment. We have developed a tandem mass spectrometry (MS/MS) method for continuous real-time determination of ambient trace levels of BTEX. The technique is based on the sampling of air via an atmospheric pressure inlet directly into the atmospheric pressure chemical ionization (APCI) source. The method is linear over four orders of magnitude, with correlation coefficients greater than 0.996. Low limits of detection in the range 1-2 microg/m(3) are achieved for BTEX. The reliability of the method was confirmed through the evaluation of quality parameters such as repeatability and reproducibility (relative standard deviation below 8% and 10%, respectively) and accuracy (over 95%). The applicability of this method to real-world samples was evaluated through measurements of BTEX levels in real ambient air samples and results were compared with a reference GC-FID method. This direct APCI-MS/MS method is suitable for real-time analysis of BTEX in ambient air during regulation surveys as well as for the monitoring of industrial processes or emergency situations.

  6. Lung cancer mortality among European rock/slag wool workers: exposure-response analysis.

    Science.gov (United States)

    Consonni, D; Boffetta, P; Andersen, A; Chang-Claude, J; Cherrie, J W; Ferro, G; Frentzel-Beyme, R; Hansen, J; Olsen, J; Plato, N; Westerholm, P; Saracci, R

    1998-08-01

    The purpose was to analyze the relationship between semi-quantitative indices of exposure to manmade vitreous fibers and lung cancer mortality among European rock/slag wool (RSW) workers. The study population comprised 9,603 male workers employed in RSW production in seven factories in Denmark, Norway, Sweden, and Germany, followed up for mortality as of 1990-91. Estimates of past exposure to respirable fibers were used to calculate cumulative exposure with a 15-year lag and maximum annual exposure based on employment history up to 1977. Rate ratios were estimated via multivariate Poisson regression, adjusting for country, age, calendar year, time since first employment, and employment status. A total of 159 lung cancer deaths were included in the analysis of which 97 among workers with more than one year of employment. We found nonstatistically significant trends in lung cancer risk according to cumulative exposure. Relative risks (RR) in the four quartiles were 1.0 (reference), 1.3 (95 percent confidence interval [CI] = 0.8-2.4), 1.2 (CI = 0.7-2.1), and 1.5 (CI = 0.7-3.0, P test for trend = 0.4). When workers with less than one year of employment were excluded, there was no increased risk; the RRs in the four quartiles were 1.0, 0.9 (CI = 0.4-2.0), 0.8 (CI = 0.3-1.9), and 1.0 (CI = 0.4-2.7). No trend was present according to maximum annual exposure. The results were not consistent among countries. We found a positive association between exposure to respirable fibers and lung cancer mortality. However, the lack of statistical significance, the dependence of the results on inclusion of short-term workers, the lack of consistency among countries, and the possible correlation between exposure to respirable fibers and to other agents reduce the weight of such evidence.

  7. A Meta-Analysis Summarizing the Effects of Pornography II: Aggression after Exposure.

    Science.gov (United States)

    Allen, Mike; And Others

    1995-01-01

    Examines by meta-analysis the effect that exposure to pornography produces on aggressive behavior under laboratory conditions considering a variety of possible moderating conditions. Demonstrates a homogeneous set of results showing that pictorial nudity reduces subsequent violent behavior, but that depictions of nonviolent sexual behavior and…

  8. Complexities of sibling analysis when exposures and outcomes change with time and birth order

    NARCIS (Netherlands)

    Sudan, Madhuri; Kheifets, Leeka I.; Arah, Onyebuchi A.; Divan, Hozefa A.; Olsen, Jørn

    2014-01-01

    In this study, we demonstrate the complexities of performing a sibling analysis with a re-examination of associations between cell phone exposures and behavioral problems observed previously in the Danish National Birth Cohort. Children (52,680; including 5441 siblings) followed up to age 7 were

  9. The effect of activated charcoal on drug exposure in healthy volunteers: a meta-analysis

    DEFF Research Database (Denmark)

    Jürgens, G; Hoegberg, L C Groth; Graudal, N A

    2009-01-01

    The objective of the study was to estimate the effect of activated charcoal (AC) administered during the first 6 h after drug intake and the effect of drug properties on drug exposure. Sixty-four controlled studies were integrated in a meta-analysis. AC administered 0-5 min after administration...

  10. A survey of environmental exposure amongst locoshed workers by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Singh, V.K.N.; Garg, A.N.

    1995-01-01

    Instrumental neutron activation analysis (INAA) has been used for the determination of 16 elements in hair of locoshed workers (n=10) to study environmental exposure. A comparison of mean elemental contents with control (n=11) shows a significant enhancement for Cr, Th, Ca, Se and Na whereas Br and Sb show a declining trend. (author). 4 refs., 1 tab

  11. Discussion about modeling the effects of neutron flux exposure for nuclear reactor core analysis

    International Nuclear Information System (INIS)

    Vondy, D.R.

    1986-04-01

    Methods used to calculate the effects of exposure to a neutron flux are described. The modeling of the nuclear-reactor core history presents an analysis challenge. The nuclide chain equations must be solved, and some of the methods in use for this are described. Techniques for treating reactor-core histories are discussed and evaluated

  12. Virtual reality exposure therapy in anxiety disorders: a quantitative meta-analysis.

    Science.gov (United States)

    Opriş, David; Pintea, Sebastian; García-Palacios, Azucena; Botella, Cristina; Szamosközi, Ştefan; David, Daniel

    2012-02-01

    Virtual reality exposure therapy (VRET) is a promising intervention for the treatment of the anxiety disorders. The main objective of this meta-analysis is to compare the efficacy of VRET, used in a behavioral or cognitive-behavioral framework, with that of the classical evidence-based treatments, in anxiety disorders. A comprehensive search of the literature identified 23 studies (n = 608) that were included in the final analysis. The results show that in the case of anxiety disorders, (1) VRET does far better than the waitlist control; (2) the post-treatment results show similar efficacy between the behavioral and the cognitive behavioral interventions incorporating a virtual reality exposure component and the classical evidence-based interventions, with no virtual reality exposure component; (3) VRET has a powerful real-life impact, similar to that of the classical evidence-based treatments; (4) VRET has a good stability of results over time, similar to that of the classical evidence-based treatments; (5) there is a dose-response relationship for VRET; and (6) there is no difference in the dropout rate between the virtual reality exposure and the in vivo exposure. Implications are discussed. © 2011 Wiley Periodicals, Inc.

  13. Staging atmospheres

    DEFF Research Database (Denmark)

    Bille, Mikkel; Bjerregaard, Peter; Sørensen, Tim Flohr

    2015-01-01

    The article introduces the special issue on staging atmospheres by surveying the philosophical, political and anthropological literature on atmosphere, and explores the relationship between atmosphere, material culture, subjectivity and affect. Atmosphere seems to occupy one of the classic...

  14. Safety of natural radiation exposure. A meta-analysis of epidemiological studies on natural radiation

    International Nuclear Information System (INIS)

    Osaki, S.

    2000-01-01

    . Furthermore, the combine of these studies, a meta-analysis, is expected to decrease the confidence limit and to countervail the confounding factors. This study reviewed the epidemiological studies on natural radiation exposure and tried to combine their results to prove the safety of natural radiation exposure. (author)

  15. Rapid analysis of the skin irritant p-phenylenediamine (PPD) in henna products using atmospheric solids analysis probe mass spectrometry.

    Science.gov (United States)

    Chen, Weiyang; Nkosi, Thobile A N; Combrinck, Sandra; Viljoen, Alvaro M; Cartwright-Jones, Catherine

    2016-09-05

    Henna (Lawsonia inermis) is applied to stain keratin, present in hair, skin and fingernails, a red-orange or rust colour. Producers of temporary tattoos mix the aromatic amine compound, para-phenylenediamine (PPD) into natural henna to create 'black henna' that rapidly stains the skin black. However, PPD may cause severe delayed hypersensitivity reactions following skin contact. This study proposes a rapid direct-analysis method to detect and identify PPD using an atmospheric solids analysis probe (ASAP) coupled to a Q-ToF mass spectrometer (MS). Since laborious, multistep methods of analysis to determine PPD are undesirable, due to the instability of the compound in solution, a screening method involving no sample preparation steps was developed. Experiments were carried out to optimise the corona current, sample cone voltage, source temperature, and desolvation gas temperature to determine ideal ASAP-Q-ToF-MS analysing conditions. Eleven of the 109 henna samples, originating from various countries, tested positive for PPD when henna products were screened using ASAP-MS, without any form of sample preparation other than grinding. Ultra-performance liquid chromatography electrospray ionisation-mass spectrometry (UPLC-Q-ToF-MS) was subsequently used to confirm the results from ASAP and to determine the concentrations of PPD in henna products. The allergen was detected in the same eleven samples, with concentrations ranging from 0.05-4.21% (w/w). It can be concluded that the sensitivity of the ASAP-MS technique is sufficient (limit of detection=0.025% w/w) to allow screening of henna samples for the presence of PPD. This relatively new technique can be applied to commercial products without extraction, sample treatment or chromatographic separation. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Chromosomal analysis and application of biological dosimetry in two cases of apparent over exposure

    International Nuclear Information System (INIS)

    Guerrero C, C.; Brena V, M.

    2002-01-01

    The gamma radiation calibration curve of 60 Co is used which was generated in the ININ Laboratory of Biology to calculate the exposure dose of two workers whose dosemeters marked values above of the limit allowed. The analysis indicates that in a first case, the aberrations frequency corresponded to the basal value, therefore there is not over exposure. The aberrations frequency of the second case is lightly above to the basal value and therefore the probability favors to what the physical dosimetry indicates. (Author)

  17. Overview on Analysis of Free Metabolites for Detection of Exposure to Chemical Warfare Agents

    Directory of Open Access Journals (Sweden)

    Grigoriu Nicoleta

    2015-06-01

    Full Text Available Chemical warfare agents (CWA’s induce complex toxicological effects with major adverse consequences for those exposed. For many chemical agents there is a need for research and development of analytical toxicological methods for a rapid and certain confirmation of those exposures. The certain methods will help for establishing the laboratory diagnosis for applying the proper therapy; the treatment of only contaminated people, decreasing the stress level in the medical community in management of crisis situations, increasing the survival rate of the population exposed to the contamination, supervision of professional exposure, judicial analysis in case of suspicious terrorist activities.

  18. Modelling ecological and human exposure to POPs in Venice lagoon - Part II: Quantitative uncertainty and sensitivity analysis in coupled exposure models.

    Science.gov (United States)

    Radomyski, Artur; Giubilato, Elisa; Ciffroy, Philippe; Critto, Andrea; Brochot, Céline; Marcomini, Antonio

    2016-11-01

    The study is focused on applying uncertainty and sensitivity analysis to support the application and evaluation of large exposure models where a significant number of parameters and complex exposure scenarios might be involved. The recently developed MERLIN-Expo exposure modelling tool was applied to probabilistically assess the ecological and human exposure to PCB 126 and 2,3,7,8-TCDD in the Venice lagoon (Italy). The 'Phytoplankton', 'Aquatic Invertebrate', 'Fish', 'Human intake' and PBPK models available in MERLIN-Expo library were integrated to create a specific food web to dynamically simulate bioaccumulation in various aquatic species and in the human body over individual lifetimes from 1932 until 1998. MERLIN-Expo is a high tier exposure modelling tool allowing propagation of uncertainty on the model predictions through Monte Carlo simulation. Uncertainty in model output can be further apportioned between parameters by applying built-in sensitivity analysis tools. In this study, uncertainty has been extensively addressed in the distribution functions to describe the data input and the effect on model results by applying sensitivity analysis techniques (screening Morris method, regression analysis, and variance-based method EFAST). In the exposure scenario developed for the Lagoon of Venice, the concentrations of 2,3,7,8-TCDD and PCB 126 in human blood turned out to be mainly influenced by a combination of parameters (half-lives of the chemicals, body weight variability, lipid fraction, food assimilation efficiency), physiological processes (uptake/elimination rates), environmental exposure concentrations (sediment, water, food) and eating behaviours (amount of food eaten). In conclusion, this case study demonstrated feasibility of MERLIN-Expo to be successfully employed in integrated, high tier exposure assessment. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Analysis of Atmospheric Nitrate Deposition in Lake Tahoe Using Multiple Oxygen Isotopes

    Science.gov (United States)

    McCabe, J. R.; Michalski, G. M.; Hernandez, L. P.; Thiemens, M. H.; Taylor, K.; Kendall, C.; Wankel, S. D.

    2002-12-01

    Lake Tahoe in the Sierra Nevada Mountain Range is world renown for its depth and water clarity bringing 2.2 million visitors per year resulting in annual revenue of \\1.6 billion from tourism. In past decades the lake has suffered from decreased water clarity (from 32 m plate depth to less than 20), which is believed to be largely the result of algae growth initiated by increased nutrient loading. Lake nutrients have also seen a shift from a nitrogen limited to a phosphorous limited system indicating a large increase in the flux of fixed nitrogen. Several sources of fixed nitrogen of have been suggested including surface runoff, septic tank seepage from ground water and deposition from the atmosphere. Bio-available nitrogen in the form of nitrate (NO_{3}$-) is a main component of this system. Recent studies have estimated that approximately 50% of the nitrogen input into the lake is of atmospheric origin (Allison et al. 2000). However, the impact and magnitude of atmospheric deposition is still one of the least understood aspects of the relationship between air and water quality in the Basin (TRPA Threshold Assessment 2002). The utility of stable isotopes as tracers of nitrate reservoirs has been shown in several studies (Bohlke et al. 1997, Kendall and McDonnell 1998, Durka et al. 1994). Stable nitrogen (δ15N) and oxygen (δ18O) isotopes have been implemented in a dual isotope approach to characterize the various nitrate sources to an ecosystem. While δ18O distinguishes between atmospheric and soil sources of nitrate, processes such as denitrification can enrich the residual nitrate in δ18O leaving a misleading atmospheric signature. The benefit of δ15N as a tracer for NO3- sources is the ability to differentiate natural soil, fertilizer, and animal or septic waste, which contain equivalent δ18O values. The recent implementation of multiple oxygen isotopes to measure Δ17O in nitrate has proven to be a more sensitive tracer of atmospheric deposition. The

  20. Air mass origins by back trajectory analysis for evaluating atmospheric 210Pb concentrations at Rokkasho, Aomori, Japan

    International Nuclear Information System (INIS)

    Akata, N.; Kawabata, H.; Hasegawa, H.; Kondo, K.; Chikuchi, Y.; Hisamatsu, S.; Inaba, J.; Sato, T.

    2009-01-01

    Atmospheric concentrations of 210 Pb change with various factors such as meso-scale meteorological conditions. We have already reported the biweekly atmospheric 210 Pb concentrations in Rokkasho, Japan for 5 years and found that they had clear seasonal variations: low concentrations in summer and high values in winter to spring. To study the reasons for the seasonal variations, the origins of the air mass flowing to Rokkasho were analyzed by 3-D backward air mass trajectory analysis. Routes of the calculated trajectories were classified into four regions: northeastern and southeastern Asian Continent, sea and other regions. The atmospheric 210 Pb concentrations were well correlated with the frequency of the routes through the northeastern Asian Continent. A non-linear multiple regression analysis of the 210 Pb concentrations and the relative frequencies of the four routes showed good fitting of the predicted values to the observed ones, and indicated that the atmospheric 210 Pb concentrations in Rokkasho depended on the frequency of the air mass from the northeastern Asian Continent. (author)

  1. Exposure to organochlorine pollutants and type 2 diabetes: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mengling Tang

    Full Text Available OBJECTIVE: Though exposure to organochlorine pollutants (OCPs is considered a risk factor for type 2 diabetes (T2DM, epidemiological evidence for the association remains controversial. A systematic review and meta-analysis was applied to quantitatively evaluate the association between exposure to OCPs and incidence of T2DM and pool the inconsistent evidence. DESIGN AND METHODS: Publications in English were searched in MEDLINE and WEB OF SCIENCE databases and related reference lists up to August 2013. Quantitative estimates and information regarding study characteristics were extracted from 23 original studies. Quality assessments of external validity, bias, exposure measurement and confounding were performed, and subgroup analyses were conducted to examine the heterogeneity sources. RESULTS: We retrieved 23 eligible articles to conduct this meta-analysis. OR (odds ratio or RR (risk ratio estimates in each subgroup were discussed, and the strong associations were observed in PCB-153 (OR, 1.52; 95% CI, 1.19-1.94, PCBs (OR, 2.14; 95% CI, 1.53-2.99, and p,p'-DDE (OR, 1.33; 95% CI, 1.15-1.54 based on a random-effects model. CONCLUSIONS: This meta-analysis provides quantitative evidence supporting the conclusion that exposure to organochlorine pollutants is associated with an increased risk of incidence of T2DM.

  2. Direct Analysis of Amphetamine Stimulants in a Whole Urine Sample by Atmospheric Solids Analysis Probe Tandem Mass Spectrometry

    Science.gov (United States)

    Crevelin, Eduardo J.; Salami, Fernanda H.; Alves, Marcela N. R.; De Martinis, Bruno S.; Crotti, Antônio E. M.; Moraes, Luiz A. B.

    2016-05-01

    Amphetamine-type stimulants (ATS) are among illicit stimulant drugs that are most often used worldwide. A major challenge is to develop a fast and efficient methodology involving minimal sample preparation to analyze ATS in biological fluids. In this study, a urine pool solution containing amphetamine, methamphetamine, ephedrine, sibutramine, and fenfluramine at concentrations ranging from 0.5 pg/mL to 100 ng/mL was prepared and analyzed by atmospheric solids analysis probe tandem mass spectrometry (ASAP-MS/MS) and multiple reaction monitoring (MRM). A urine sample and saliva collected from a volunteer contributor (V1) were also analyzed. The limit of detection of the tested compounds ranged between 0.002 and 0.4 ng/mL in urine samples; the signal-to-noise ratio was 5. These results demonstrated that the ASAP-MS/MS methodology is applicable for the fast detection of ATS in urine samples with great sensitivity and specificity, without the need for cleanup, preconcentration, or chromatographic separation. Thus ASAP-MS/MS could potentially be used in clinical and forensic toxicology applications.

  3. Environmental Polychlorinated Biphenyl Exposure and Breast Cancer Risk: A Meta-Analysis of Observational Studies.

    Directory of Open Access Journals (Sweden)

    Jingwen Zhang

    Full Text Available Association between polychlorinated biphenyl (PCB exposure and breast cancer risk has been widely studied, but the results remain controversial. We performed a meta-analysis to evaluate the evidences from observational studies on PCB exposure and breast cancer risk.Relevant studies with data on internal PCB dose were identified from PubMed, EMBASE, CBM and CNKI databases through November 2014. Multivariable-adjusted odds ratio (OR with 95% confidence intervals (CIs were applied to assess the association between PCB exposure and breast cancer risk. Heterogeneity test, sensitivity analysis, subgroup analysis and publication bias test were also performed. To further explore the association between specific groups of PCB congeners and breast cancer, we examined the PCB congeners classified, according to their structural, biological and pharmacokinetics properties, as group I (potentially estrogenic, group II (potentially anti-estrogenic and immunotoxic, dioxin-like, and group III (phenobarbital, CYP1A and CYP2B inducers, biologically persistent.Of 660 studies screened, 25 studies which met criteria were selected, involving a total of 12866 participants (6088 cases and 6778 controls from eight countries. The results showed that the risk of breast cancer was associated with group II (OR = 1.23, 95% CI: 1.08-1.40 and group III (OR = 1.25, 95% CI: 1.09-1.43 PCBs, but not with group I (OR = 1.10, 95%CI: 0.97-1.24 PCBs or total PCB exposure (OR = 1.09, 95%CI: 0.97-1.22.Our meta-analysis based on the selected studies found group II and group III PCB exposure might contribute to the risk of breast cancer. More studies in developing countries with higher PCB levels are needed, as well as studies to explore the relationships between mixtures of organochlorine compounds and breast cancer risk.

  4. Looking for biomarkers of Hg exposure by transcriptome analysis in the aquatic plant Elodea nuttallii

    Directory of Open Access Journals (Sweden)

    Regier N.

    2013-04-01

    Full Text Available Recently developed genomics tools have a promising potential to identify early biomarkers of exposure to toxicants. In the present work we used transcriptome analysis (RNA-seq of Elodea nuttallii –an invasive rooted macrophyte that is able to accumulate large amounts of metals- to identify biomarkers of Hg exposure. RNA-seq allowed identification of genes affected by Hg exposure and also unraveled plant response to the toxic metal: a change in energy/reserve metabolism caused by the inhibition of photosynthesis, and an adaptation of homeostasis networks to control accumulation of Hg. Data were validated by RT-qPCR and selected genes were further tested as biomarkers. Samples exposed in the field and to natural contaminated sediments clustered well with samples exposed to low metal concentrations under laboratory conditions. Our data suggest that this plant and/or this approach could be useful to develop new tests for water and sediment quality assessment.

  5. Tooth Matrix Analysis for Biomonitoring of Organic Chemical Exposure: Current Status, Challenges, and Opportunities

    Science.gov (United States)

    Andra, Syam S.; Austin, Christine; Arora, Manish

    2015-01-01

    Epidemiological evidence supports associations between prenatal exposure to environmental organic chemicals and childhood health impairments. Unlike the common choice of biological matrices such as urine and blood that can be limited by short half-lives for some chemicals, teeth provide a stable repository for chemicals with half-life in the order of decades. Given the potential of the tooth bio-matrix to study long-term exposures to environmental organic chemicals in human biomonitoring programs, it is important to be aware of possible pitfalls and potential opportunities to improve on the current analytical method for tooth organics analysis. We critically review previous results of studies of this topic. The major drawbacks and challenges in currently practiced concepts and analytical methods in utilizing tooth bio-matrix are (i) no consideration of external (from outer surface) or internal contamination (from micro odontoblast processes), (ii) the misleading assumption that whole ground teeth represent prenatal exposures (latest formed dentine is lipid rich and therefore would absorb and accumulate more organic chemicals), (iii) reverse causality in exposure assessment due to whole ground teeth, and (iv) teeth are a precious bio-matrix and grinding them raises ethical concerns about appropriate use of a very limited resource in exposure biology and epidemiology studies. These can be overcome by addressing the important limitations and possible improvements with the analytical approach associated at each of the following steps (i) tooth sample preparation to retain exposure timing, (ii) organics extraction and pre-concentration to detect ultra-trace levels of analytes, (iii) chromatography separation, (iv) mass spectrometric detection to detect multi-class organics simultaneously, and (v) method validation, especially to exclude chance findings. To highlight the proposed improvements we present findings from a pilot study that utilizes tooth matrix biomarkers to

  6. Children's Lead Exposure: A Multimedia Modeling Analysis to Guide Public Health Decision-Making.

    Science.gov (United States)

    Zartarian, Valerie; Xue, Jianping; Tornero-Velez, Rogelio; Brown, James

    2017-09-12

    Drinking water and other sources for lead are the subject of public health concerns around the Flint, Michigan, drinking water and East Chicago, Indiana, lead in soil crises. In 2015, the U.S. Environmental Protection Agency (EPA)'s National Drinking Water Advisory Council (NDWAC) recommended establishment of a "health-based, household action level" for lead in drinking water based on children's exposure. The primary objective was to develop a coupled exposure-dose modeling approach that can be used to determine what drinking water lead concentrations keep children's blood lead levels (BLLs) below specified values, considering exposures from water, soil, dust, food, and air. Related objectives were to evaluate the coupled model estimates using real-world blood lead data, to quantify relative contributions by the various media, and to identify key model inputs. A modeling approach using the EPA's Stochastic Human Exposure and Dose Simulation (SHEDS)-Multimedia and Integrated Exposure Uptake and Biokinetic (IEUBK) models was developed using available data. This analysis for the U.S. population of young children probabilistically simulated multimedia exposures and estimated relative contributions of media to BLLs across all population percentiles for several age groups. Modeled BLLs compared well with nationally representative BLLs (0-23% relative error). Analyses revealed relative importance of soil and dust ingestion exposure pathways and associated Pb intake rates; water ingestion was also a main pathway, especially for infants. This methodology advances scientific understanding of the relationship between lead concentrations in drinking water and BLLs in children. It can guide national health-based benchmarks for lead and related community public health decisions. https://doi.org/10.1289/EHP1605.

  7. Antibiotic exposure in neonates and early adverse outcomes: a systematic review and meta-analysis.

    Science.gov (United States)

    Esaiassen, Eirin; Fjalstad, Jon Widding; Juvet, Lene Kristine; van den Anker, John N; Klingenberg, Claus

    2017-07-01

    To systematically review and meta-analyse the relationship between antibiotic exposure in neonates and the following early adverse outcomes: necrotizing enterocolitis (NEC), invasive fungal infections (IFIs) and/or death. Data sources were PubMed, Embase, Medline and the Cochrane Database (to December 2016), supplemented by manual searches of reference lists. Randomized controlled trials (RCTs) and observational studies were included if they provided data on different categories of antibiotic exposures (yes versus no, long versus short duration, and/or broad- versus narrow-spectrum regimens) and the risk of developing NEC, IFI and/or death in the neonatal period. Two reviewers extracted data and evaluated the risk of bias using the Cochrane Handbook, adapted to include observational studies. When appropriate, meta-analyses were conducted using the random-effect model. We identified 9 RCTs and 38 observational studies. The quality of the majority of studies was poor to moderate. There was a significant association between prolonged antibiotic exposure and an increased risk of NEC in five observational studies (5003 participants) and/or risk of death in five observational studies (13 534 participants). Eleven of 15 studies with data on broad- versus narrow-spectrum regimens reported an increased risk of IFI after broad-spectrum antibiotic exposure, in particular with third-generation cephalosporins and carbapenems. Meta-analysis was limited by few and old RCTs, insufficient sample sizes and diversity of antibiotic exposure and outcomes reported. Prolonged antibiotic exposure in uninfected preterm infants is associated with an increased risk of NEC and/or death, and broad-spectrum antibiotic exposure is associated with an increased risk of IFI. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Emulation of simulations of atmospheric dispersion at Fukushima for Sobol' sensitivity analysis

    Science.gov (United States)

    Girard, Sylvain; Korsakissok, Irène; Mallet, Vivien

    2015-04-01

    Polyphemus/Polair3D, from which derives IRSN's operational model ldX, was used to simulate the atmospheric dispersion at the Japan scale of radionuclides after the Fukushima disaster. A previous study with the screening method of Morris had shown that - The sensitivities depend a lot on the considered output; - Only a few of the inputs are non-influential on all considered outputs; - Most influential inputs have either non-linear effects or are interacting. These preliminary results called for a more detailed sensitivity analysis, especially regarding the characterization of interactions. The method of Sobol' allows for a precise evaluation of interactions but requires large simulation samples. Gaussian process emulators for each considered outputs were built in order to relieve this computational burden. Globally aggregated outputs proved to be easy to emulate with high accuracy, and associated Sobol' indices are in broad agreement with previous results obtained with the Morris method. More localized outputs, such as temporal averages of gamma dose rates at measurement stations, resulted in lesser emulator performances: tests simulations could not satisfactorily be reproduced by some emulators. These outputs are of special interest because they can be compared to available observations, for instance for calibration purpose. A thorough inspection of prediction residuals hinted that the model response to wind perturbations often behaved in very distinct regimes relatively to some thresholds. Complementing the initial sample with wind perturbations set to the extreme values allowed for sensible improvement of some of the emulators while other remained too unreliable to be used in a sensitivity analysis. Adaptive sampling or regime-wise emulation could be tried to circumvent this issue. Sobol' indices for local outputs revealed interesting patterns, mostly dominated by the winds, with very high interactions. The emulators will be useful for subsequent studies. Indeed

  9. Radiation exposure due to local fallout from Soviet atmospheric nuclear weapons testing in Kazakhstan: solid cancer mortality in the Semipalatinsk historical cohort, 1960-1999.

    Science.gov (United States)

    Bauer, Susanne; Gusev, Boris I; Pivina, Ludmila M; Apsalikov, Kazbek N; Grosche, Bernd

    2005-10-01

    Little information is available on the health effects of exposures to fallout from Soviet nuclear weapons testing and on the combined external and internal environmental exposures that have resulted from these tests. This paper reports the first analysis of the Semipalatinsk historical cohort exposed in the vicinity of the Semipalatinsk nuclear test site, Kazakhstan. The cohort study, which includes 19,545 inhabitants of exposed and comparison villages of the Semipalatinsk region, was set up in the 1960s and comprises 582,750 person-years of follow-up between 1960 and 1999. Cumulative effective radiation dose estimates in this cohort range from 20 mSv to approximately 4 Sv. Rates of mortality and cancer mortality in the exposed group substantially exceeded those of the comparison group. Dose-response analyses within the exposed group confirmed a significant trend with dose for all solid cancers (P sites, a significant trend with dose was observed for lung cancer (P = 0.0001), stomach cancer (P = 0.0050), and female breast cancer (P = 0.0040) as well as for esophagus cancer in women (P = 0.0030). The excess relative risk per sievert for all solid cancers combined was 1.77 (1.35; 2.27) based on the total cohort data, yet a selection bias regarding the comparison group could not be entirely ruled out. The excess relative risk per sievert based on the cohort's exposed group was 0.81 (0.46; 1.33) for all solid cancers combined and thus still exceeds current risk estimates from the Life Span Study. Future epidemiological assessments based on this cohort will benefit from extension of follow-up and ongoing validation of dosimetric data.

  10. Characterization of regional atmospheric aerosols over Hungary by PIXE elemental analysis

    International Nuclear Information System (INIS)

    Koltay, E.; Szabo, G.; Borbely Kiss, I.; Somorjai, E.; Kiss, A.Z.

    1994-01-01

    Studying the characteristic features of atmospheric aerosols emitted by natural and anthropogenic sources is of basic importance for a detailed understanding of the physics and chemistry of the atmosphere. Environmental pollution by atmospheric aerosols and their impact can be tested in the same way, too. The separation of natural and anthropogenic components of the aerosol can be done through enrichment factors and size distribution curves deduced from analytical information. The Particle Induced X-ray Emission (PIXE) technique has been applied in aerosol studies by the authors. Results obtained on atmospheric aerosols collected over Hungary and presented in terms of concentrations, enrichment factors, regional signatures, deposition velocities, transport properties and apportionment of sources illustrate the scope and proportions of the potential contribution of PIXE to the methodology of atmospheric aerosol studies. Continued activity planned in the framework of the present CRP may widen the scope of the investigations mainly in the field of size-fractioned sampling and - possibly - in the direction of individual characterization of aerosol particles. (author). 14 refs

  11. New insight into atmospheric mercury emissions from zinc smelters using mass flow analysis.

    Science.gov (United States)

    Wu, Qingru; Wang, Shuxiao; Hui, Mulin; Wang, Fengyang; Zhang, Lei; Duan, Lei; Luo, Yao

    2015-03-17

    The mercury (Hg) flow paths from three zinc (Zn) smelters indicated that a large quantity of Hg, approximately 38.0-57.0% of the total Hg input, was stored as acid slag in the landfill sites. Approximately 15.0-27.1% of the Hg input was emitted into water or stored as open-dumped slags, and 3.3-14.5% of the Hg input ended in sulfuric acid. Atmospheric Hg emissions, accounting for 1.4-9.6% of the total Hg input, were from both the Zn production and waste disposal processes. Atmospheric Hg emissions from the waste disposal processes accounted for 40.6, 89.6, and 94.6% of the total atmospheric Hg emissions of the three studied smelters, respectively. The Zn production process mainly contributed to oxidized Hg (Hg2+) emissions, whereas the waste disposal process generated mostly elemental Hg (Hg0) emissions. When the emissions from these two processes are considered together, the emission proportion of the Hg2+ mass was 51, 46, and 29% in smelters A, B, and C, respectively. These results indicated that approximately 10.8±5.8 t of atmospheric Hg emissions from the waste disposal process were ignored in recent inventories. Therefore, the total atmospheric Hg emissions from the Zn industry of China should be approximately 50 t.

  12. Exposure to pesticides and diabetes: A systematic review and meta-analysis.

    Science.gov (United States)

    Evangelou, Evangelos; Ntritsos, Georgios; Chondrogiorgi, Maria; Kavvoura, Fotini K; Hernández, Antonio F; Ntzani, Evangelia E; Tzoulaki, Ioanna

    2016-05-01

    Diabetes mellitus has a multifactorial pathogenesis with a strong genetic component as well as many environmental and lifestyle influences. Emerging evidence suggests that environmental contaminants, including pesticides, might play an important role in the pathogenesis of diabetes. We performed a systematic review and meta-analysis of observational studies that assessed the association between exposure to pesticides and diabetes and we examined the presence of heterogeneity and biases across available studies. A comprehensive literature search of peer-reviewed original research pertaining to pesticide exposure and diabetes, published until 30st May 2015, with no language restriction, was conducted. Eligible studies were those that investigated potential associations between pesticides and diabetes without restrictions on diabetes type. We included cohort studies, case-control studies and cross-sectional studies. We extracted information on study characteristics, type of pesticide assessed, exposure assessment, outcome definition, effect estimate and sample size. We identified 22 studies assessing the association between pesticides and diabetes. The summary OR for the association of top vs. bottom tertile of exposure to any type of pesticide and diabetes was 1.58 (95% CI: 1.32-1.90, p=1.21×10(-6)), with large heterogeneity (I(2)=66.8%). Studies evaluating Type 2 diabetes in particular (n=13 studies), showed a similar summary effect comparing top vs. bottom tertiles of exposure: 1.61 (95% CI 1.37-1.88, p=3.51×10(-9)) with no heterogeneity (I(2)=0%). Analysis by type of pesticide yielded an increased risk of diabetes for DDE, heptachlor, HCB, DDT, and trans-nonachlor or chlordane. The epidemiological evidence, supported by mechanistic studies, suggests an association between exposure to organochlorine pesticides and Type 2 diabetes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Does D-cycloserine enhance exposure therapy for anxiety disorders in humans? A meta-analysis.

    Directory of Open Access Journals (Sweden)

    Helga Rodrigues

    Full Text Available The treatment of anxiety is on the edge of a new era of combinations of pharmacologic and psychosocial interventions. A new wave of translational research has focused on the use of pharmacological agents as psychotherapy adjuvants using neurobiological insights into the mechanism of the action of certain psychological treatments such as exposure therapy. Recently, d-cycloserine (DCS an antibiotic used to treat tuberculosis has been applied to enhance exposure-based treatment for anxiety and has proved to be a promising, but as yet unproven intervention. The present study aimed to evaluate the efficacy of DCS in the enhancement of exposure therapy in anxiety disorders. A systematic review/meta-analysis was conducted. Electronic searches were conducted in the databases ISI-Web of Science, Pubmed and PsycINFO. We included only randomized, double-blind, placebo-controlled trials with humans, focusing on the role of DCS in enhancing the action of exposure therapy for anxiety disorders. We identified 328 references, 13 studies were included in our final sample: 4 on obsessive-compulsive disorder, 2 on panic disorder, 2 on social anxiety disorder, 2 on posttraumatic stress disorder, one on acrophobia, and 2 on snake phobia. The results of the present meta-analysis show that DCS enhances exposure therapy in the treatment of anxiety disorders (Cohen d =  -0.34; CI: -0.54 to -0.14, facilitating the specific process of extinction of fear. DCS seems to be effective when administered at a time close to the exposure therapy, at low doses and a limited number of times. DCS emerges as a potential new therapeutic approach for patients with refractory anxiety disorders that are unresponsive to the conventional treatments available. When administered correctly, DCS is a promising strategy for augmentation of CBT and could reduce health care costs, drop-out rates and bring faster relief to patients.

  14. Effects of glyphosate exposure on sperm concentration in rodents: A systematic review and meta-analysis.

    Science.gov (United States)

    Cai, Wenyan; Ji, Ying; Song, Xianping; Guo, Haoran; Han, Lei; Zhang, Feng; Liu, Xin; Zhang, Hengdong; Zhu, Baoli; Xu, Ming

    2017-10-01

    Correlation between exposure to glyphosate and sperm concentrations is important in reproductive toxicity risk assessment for male reproductive functions. Many studies have focused on reproductive toxicity on glyphosate, however, results are still controversial. We conducted a systematic review of epidemiological studies on the association between glyphosate exposure and sperm concentrations of rodents. The aim of this study is to explore the potential adverse effects of glyphosate on reproductive function of male rodents. Systematic and comprehensive literature search was performed in MEDLINE, TOXLINE, Embase, WANFANG and CNKI databases with different combinations of glyphosate exposure and sperm concentration. 8 studies were eventually identified and random-effect model was conducted. Heterogeneity among study results was calculated via chi-square tests. Ten independent experimental datasets from these eight studies were acquired to synthesize the random-effect model. A decrease in sperm concentrations was found with mean difference of sperm concentrations(MDsperm)=-2.774×10 6 /sperm/g/testis(95%CI=-0.969 to -4.579) in random-effect model after glyphosate exposure. There was also a significant decrease after fitting the random-effect model: MDsperm=-1.632×10 6 /sperm/g/testis (95%CI=-0.662 to -2.601). The results of meta-analysis support the hypothesis that glyphosate exposure decreased sperm concentration in rodents. Therefore, we conclude that glyphosate is toxic to male rodent's reproductive system. Copyright © 2017. Published by Elsevier B.V.

  15. Analysis of cosmic ray atmosphere passage in the light of scaling violation

    International Nuclear Information System (INIS)

    Erlykin, A.D.; Kuzina, N.P.

    1981-01-01

    The multigroup method has been used to analyze the passage of cosmic rays through the Earth atmosphere. Initial spectra of Nikolsky, Rayan and Grigorov are used in calculations. Differential energy spectra of electrons, photons on different depths in the atmosphere and hadrons at the mountain and sea level for the energy range of 10 11 -10 14 eV, are presented. The comparison of calculations with experiments shows that the cross section of the interaction of cosmic rays with the atmosphere rises in the manner of ln 2 E depending on energy. Cross section growth is largely conditioned by processes with high inelasticity. Interaction multiplicity grows in the manner of Esup(1/4). Scaling in the fragmentation range of inclusion spectra of secondary particles is violated [ru

  16. Retrieval and analysis of atmospheric XCO2 using ground-based spectral observation.

    Science.gov (United States)

    Qin, Xiu-Chun; Lei, Li-Ping; Kawasaki, Masahiro; Masafumi, Ohashi; Takahiro, Kuroki; Zeng, Zhao-Cheng; Zhang, Bing

    2014-07-01

    Atmospheric CO2 column concentration (column-averaged dry air mole fractions of atmospheric carbon dioxide) data obtained by ground-based hyperspectral observation is an important source of data for the verification and improvement of the results of CO2 retrieval based on satellite hyperspectral observation. However, few studies have been conducted on atmospheric CO2 column concentration retrieval based on ground-based spectral hyperspectral observation in China. In the present study, we carried out the ground-based hyperspectral observation in Xilingol Grassland, Inner Mongolia of China by using an observation system which is consisted of an optical spectral analyzer, a sun tracker, and some other elements. The atmospheric CO2 column concentration was retrieved using the observed hyperspectral data. The effect of a wavelength shift of the observation spectra and the meteorological parameters on the retrieval precision of the atmospheric CO2 concentration was evaluated and analyzed. The results show that the mean value of atmospheric CO2 concentration was 390.9 microg x mL(-1) in the study area during the observing period from July to September. The shift of wavelength in the range between -0.012 and 0.042 nm will generally lead to 1 microg x mL(-1) deviation in the CO2 retrievals. This study also revealed that the spectral transmittance was sensitive to meteorological parameters in the wavelength range of 6 357-6 358, 6 360-6 361, and 6 363-6 364 cm(-1). By comparing the CO2 retrievals derived from the meteorological parameters observed in synchronous and non-synchronous time, respectively, with the spectral observation, it was showed that the concentration deviation caused by using the non-synchronously observed meteorological parameters is ranged from 0.11 to 4 microg x mL(-1). These results can be used as references for the further improvement of retrieving CO2 column concentration based on spectral observation.

  17. Measurement and analysis of ambient atmospheric particulate matter in urban and remote environments

    Science.gov (United States)

    Hagler, Gayle S. W.

    Atmospheric particulate matter pollution is a challenging environmental concern in both urban and remote locations worldwide. It is intrinsically difficult to control, given numerous anthropogenic and natural sources (e.g. fossil fuel combustion, biomass burning, dust, and seaspray) and atmospheric transport up to thousands of kilometers after production. In urban regions, fine particulate matter (particles with diameters under 2.5 mum) is of special concern for its ability to penetrate the human respiratory system and threaten cardiopulmonary health. A second major impact area is climate, with particulate matter altering Earth's radiative balance through scattering and absorbing solar radiation, modifying cloud properties, and reducing surface reflectivity after deposition in snow-covered regions. While atmospheric particulate matter has been generally well-characterized in populated areas of developed countries, particulate pollution in developing nations and remote regions is relatively unexplored. This thesis characterizes atmospheric particulate matter in locations that represent the extreme ends of the spectrum in terms of air pollution-the rapidly-developing and heavily populated Pearl River Delta Region of China, the pristine and climate-sensitive Greenland Ice Sheet, and a remote site in the Colorado Rocky Mountains. In China, fine particles were studied through a year-long field campaign at seven sites surrounding the Pearl River Delta. Fine particulate matter was analyzed for chemical composition, regional variation, and meteorological impacts. On the Greenland Ice Sheet and in the Colorado Rocky Mountains, the carbonaceous fraction (organic and elemental carbon) of particulate matter was studied in the atmosphere and snow pack. Analyses included quantifying particulate chemical and optical properties, assessing atmospheric transport, and evaluating post-depositional processing of carbonaceous species in snow.

  18. PIXE analysis of atmospheric aerosols in the city of Buenos Aires

    International Nuclear Information System (INIS)

    Ozafran, M.J.; Vazquez, M.E.; Burlon, A.

    1999-01-01

    Lead pollution present in atmospheric aerosols in the city Buenos Aires was measured in 1989, using Heavy Ion PIXE. Since then, environmental conditions have changed significantly. The usage of unleaded gasoline was introduced, and the utilisation of compressed natural gas as car fuel has increased. Recently, a new sampling campaign of atmospheric aerosols has started, partly in collaboration with the Greenpeace Foundation. The present studies reveal that lead pollution in Buenos Aires has significantly decreased since 1989. The concentrations of other elements are determined as well. (author)

  19. [Paternal exposure to occupational electromagnetic radiation and sex ratio of the offspring: a meta-analysis].

    Science.gov (United States)

    Tong, Shu-Hui; Liu, Yi-Ting; Liu, Yang

    2013-02-01

    To investigate the association between paternal exposure to occupational electromagnetic radiation and the sex ratio of the offspring. We searched various databases, including PubMed, Embase, Cochrane Library, OVID, Bioscience Information Service (BIOSIS), China National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals and Wanfang Database, for the literature relevant to the association of paternal exposure to occupational electromagnetic radiation with the sex ratio of the offspring. We conducted a meta-analysis on their correlation using Stata 11.0. There was no statistically significant difference in the sex ratio between the offspring with paternal exposure to occupational electromagnetic radiation and those without (pooled OR = 1.00 [95% CI: 0.95 -1.05], P = 0.875). Subgroup analysis of both case-control and cohort studies revealed no significant difference (pooled OR = 1.03 [95% CI: 0.99 -1.08], P = 0.104 and pooled OR = 0.98 [95% CI: 0.99 -1.08], P = 0.186, respectively). Paternal exposure to occupational electromagnetic radiation is not correlated with the sex ratio of the offspring.

  20. Complexities of sibling analysis when exposures and outcomes change with time and birth order.

    Science.gov (United States)

    Sudan, Madhuri; Kheifets, Leeka I; Arah, Onyebuchi A; Divan, Hozefa A; Olsen, Jørn

    2014-01-01

    In this study, we demonstrate the complexities of performing a sibling analysis with a re-examination of associations between cell phone exposures and behavioral problems observed previously in the Danish National Birth Cohort. Children (52,680; including 5441 siblings) followed up to age 7 were included. We examined differences in exposures and behavioral problems between siblings and non-siblings and by birth order and birth year. We estimated associations between cell phone exposures and behavioral problems while accounting for the random family effect among siblings. The association of behavioral problems with both prenatal and postnatal exposure differed between siblings (odds ratio (OR): 1.07; 95% confidence interval (CI): 0.69-1.66) and non-siblings (OR: 1.54; 95% CI: 1.36-1.74) and within siblings by birth order; the association was strongest for first-born siblings (OR: 1.72; 95% CI: 0.86-3.42) and negative for later-born siblings (OR: 0.63; 95% CI: 0.31-1.25), which may be because of increases in cell phone use with later birth year. Sibling analysis can be a powerful tool for (partially) accounting for confounding by invariant unmeasured within-family factors, but it cannot account for uncontrolled confounding by varying family-level factors, such as those that vary with time and birth order.

  1. The use of caffeine to assess high dose exposures to ionising radiation by dicentric analysis

    International Nuclear Information System (INIS)

    Pujol, M.; Puig, R.; Caballin, M. R.; Barrios, L.; Barquinero, J. F.

    2012-01-01

    Dicentric analysis is considered as a 'gold standard' method for biological dosimetry. However, due to the radiation-induced mitotic delay or inability to reach mitosis of heavily damaged cells, the analysis of dicentrics is restricted to doses up to 4-5 Gy. For higher doses, the analysis by premature chromosome condensation technique has been proposed. Here, it is presented a preliminary study is presented in which an alternative method to analyse dicentrics after high dose exposures to ionising radiation (IR) is evaluated. The method is based on the effect of caffeine in preventing the G2/M checkpoint allowing damaged cells to reach mitosis. The results obtained indicate that the co-treatment with Colcemide and caffeine increases significantly increases the mitotic index, and hence allows a more feasible analysis of dicentrics. Moreover in the dose range analysed, from 0 to 15 Gy, the dicentric cell distribution followed the Poisson distribution, and a simulated partial-body exposure has been clearly detected. Overall, the results presented here suggest that caffeine has a great potential to be used for dose-assessment after high dose exposure to IR. (authors)

  2. Analysis of Aviation Safety Reporting System Incident Data Associated with the Technical Challenges of the Atmospheric Environment Safety Technology Project

    Science.gov (United States)

    Withrow, Colleen A.; Reveley, Mary S.

    2014-01-01

    This study analyzed aircraft incidents in the NASA Aviation Safety Reporting System (ASRS) that apply to two of the three technical challenges (TCs) in NASA's Aviation Safety Program's Atmospheric Environment Safety Technology Project. The aircraft incidents are related to airframe icing and atmospheric hazards TCs. The study reviewed incidents that listed their primary problem as weather or environment-nonweather between 1994 and 2011 for aircraft defined by Federal Aviation Regulations (FAR) Parts 121, 135, and 91. The study investigated the phases of flight, a variety of anomalies, flight conditions, and incidents by FAR part, along with other categories. The first part of the analysis focused on airframe-icing-related incidents and found 275 incidents out of 3526 weather-related incidents over the 18-yr period. The second portion of the study focused on atmospheric hazards and found 4647 incidents over the same time period. Atmospheric hazards-related incidents included a range of conditions from clear air turbulence and wake vortex, to controlled flight toward terrain, ground encounters, and incursions.

  3. System analysis and test-bed for an atmosphere-breathing electric propulsion system using an inductive plasma thruster

    Science.gov (United States)

    Romano, F.; Massuti-Ballester, B.; Binder, T.; Herdrich, G.; Fasoulas, S.; Schönherr, T.

    2018-06-01

    Challenging space mission scenarios include those in low altitude orbits, where the atmosphere creates significant drag to the S/C and forces their orbit to an early decay. For drag compensation, propulsion systems are needed, requiring propellant to be carried on-board. An atmosphere-breathing electric propulsion system (ABEP) ingests the residual atmosphere particles through an intake and uses them as propellant for an electric thruster. Theoretically applicable to any planet with atmosphere, the system might allow to orbit for unlimited time without carrying propellant. A new range of altitudes for continuous operation would become accessible, enabling new scientific missions while reducing costs. Preliminary studies have shown that the collectible propellant flow for an ion thruster (in LEO) might not be enough, and that electrode erosion due to aggressive gases, such as atomic oxygen, will limit the thruster lifetime. In this paper an inductive plasma thruster (IPT) is considered for the ABEP system. The starting point is a small scale inductively heated plasma generator IPG6-S. These devices are electrodeless and have already shown high electric-to-thermal coupling efficiencies using O2 and CO2 . The system analysis is integrated with IPG6-S tests to assess mean mass-specific energies of the plasma plume and estimate exhaust velocities.

  4. Metadata database and data analysis software for the ground-based upper atmospheric data developed by the IUGONET project

    Science.gov (United States)

    Hayashi, H.; Tanaka, Y.; Hori, T.; Koyama, Y.; Shinbori, A.; Abe, S.; Kagitani, M.; Kouno, T.; Yoshida, D.; Ueno, S.; Kaneda, N.; Yoneda, M.; Tadokoro, H.; Motoba, T.; Umemura, N.; Iugonet Project Team

    2011-12-01

    The Inter-university Upper atmosphere Global Observation NETwork (IUGONET) is a Japanese inter-university project by the National Institute of Polar Research (NIPR), Tohoku University, Nagoya University, Kyoto University, and Kyushu University to build a database of metadata for ground-based observations of the upper atmosphere. The IUGONET institutes/universities have been collecting various types of data by radars, magnetometers, photometers, radio telescopes, helioscopes, etc. at various locations all over the world and at various altitude layers from the Earth's surface to the Sun. The metadata database will be of great help to researchers in efficiently finding and obtaining these observational data spread over the institutes/universities. This should also facilitate synthetic analysis of multi-disciplinary data, which will lead to new types of research in the upper atmosphere. The project has also been developing a software to help researchers download, visualize, and analyze the data provided from the IUGONET institutes/universities. The metadata database system is built on the platform of DSpace, which is an open source software for digital repositories. The data analysis software is written in the IDL language with the TDAS (THEMIS Data Analysis Software suite) library. These products have been just released for beta-testing.

  5. [Establishment and assessment of QA/QC method for sampling and analysis of atmosphere background CO2].

    Science.gov (United States)

    Liu, Li-xin; Zhou, Ling-xi; Xia, Ling-jun; Wang, Hong-yang; Fang, Shuang-xi

    2014-12-01

    To strengthen scientific management and sharing of greenhouse gas data obtained from atmospheric background stations in China, it is important to ensure the standardization of quality assurance and quality control method for background CO2 sampling and analysis. Based on the greenhouse gas sampling and observation experience of CMA, using portable sampling observation and WS-CRDS analysis technique as an example, the quality assurance measures for atmospheric CO,sampling and observation in the Waliguan station (Qinghai), the glass bottle quality assurance measures and the systematic quality control method during sample analysis, the correction method during data processing, as well as the data grading quality markers and data fitting interpolation method were systematically introduced. Finally, using this research method, the CO2 sampling and observation data at the atmospheric background stations in 3 typical regions were processed and the concentration variation characteristics were analyzed, indicating that this research method could well catch the influences of the regional and local environmental factors on the observation results, and reflect the characteristics of natural and human activities in an objective and accurate way.

  6. Genetic algorithm applied to a Soil-Vegetation-Atmosphere system: Sensitivity and uncertainty analysis

    Science.gov (United States)

    Schneider, Sébastien; Jacques, Diederik; Mallants, Dirk

    2010-05-01

    Numerical models are of precious help for predicting water fluxes in the vadose zone and more specifically in Soil-Vegetation-Atmosphere (SVA) systems. For such simulations, robust models and representative soil hydraulic parameters are required. Calibration of unsaturated hydraulic properties is known to be a difficult optimization problem due to the high non-linearity of the water flow equations. Therefore, robust methods are needed to avoid the optimization process to lead to non-optimal parameters. Evolutionary algorithms and specifically genetic algorithms (GAs) are very well suited for those complex parameter optimization problems. Additionally, GAs offer the opportunity to assess the confidence in the hydraulic parameter estimations, because of the large number of model realizations. The SVA system in this study concerns a pine stand on a heterogeneous sandy soil (podzol) in the Campine region in the north of Belgium. Throughfall and other meteorological data and water contents at different soil depths have been recorded during one year at a daily time step in two lysimeters. The water table level, which is varying between 95 and 170 cm, has been recorded with intervals of 0.5 hour. The leaf area index was measured as well at some selected time moments during the year in order to evaluate the energy which reaches the soil and to deduce the potential evaporation. Water contents at several depths have been recorded. Based on the profile description, five soil layers have been distinguished in the podzol. Two models have been used for simulating water fluxes: (i) a mechanistic model, the HYDRUS-1D model, which solves the Richards' equation, and (ii) a compartmental model, which treats the soil profile as a bucket into which water flows until its maximum capacity is reached. A global sensitivity analysis (Morris' one-at-a-time sensitivity analysis) was run previously to the calibration, in order to check the sensitivity in the chosen parameter search space. For

  7. CNTB program for the analysis of partially mixed containment atmospheres during depressurization events

    International Nuclear Information System (INIS)

    Landoni, J.A.

    1979-07-01

    This program describes the analytical models for the CNTB computer program, which is permanently filed in the archive library of the General Atomic (GA) San Diego Data Center under reference number THSD-2699. Developed during the last four years, this computer program has been successfully applied in its presented form to the type of containment atmosphere transients illustrated in this report. For example, the CNTB computer program is applicable (1) to the design basis depressurization accident (DBDA) to determine the effect of the partial mixing on the containment atmospheric peak pressure (known as nonmixing penalty) and (2) for Class 9 accidents, such as the loss of forced circulation (LOFC), for the AIPA Phase I studies. The capability of the CNTB computer program has been substantially improved over its precursor, the CONTEMPT-G computer program, to predict the thermodynamic behavior of the containment atmosphere during helium releases, assuming partial mixing of the original air with the effluent and to predict the amount of the environmental leaks under closed and open containment conditions. In addition, the CNTB computer program running times are considerably below the ones required for the CONTEMPT-G computer program. Computational solution of the variable parameters in the containment atmosphere is effected by an iterative technique, while the temperatures for its boundaries are obtained by finite differences. The CNTB computer program, written in FORTRAN V, has been implemented at GA on the UNIVAC 1110 computer

  8. Effects of methimazole and propylthiouracil exposure during pregnancy on the risk of neonatal congenital malformations: A meta-analysis

    Science.gov (United States)

    Song, Rongjing; Lin, Hepu; Chen, Yue; Zhang, Xiuying

    2017-01-01

    Objective The aim of this study was to determine the effect of exposure to different antithyroid drugs during pregnancy on the incidence of neonatal congenital malformations. Methods A meta-analysis was performed to compare the incidence of neonatal congenital malformations after exposure to different antithyroid drugs during pregnancy. Twelve studies that met the inclusion criteria were included in this meta-analysis. PubMed, Embase, and CENTRAL databases were searched from inception until January 2017. Study designs included case–control studies, prospective cohort studies, and retrospective cohort studies. Results Twelve studies involving 8028 participants with exposure to different antithyroid drugs during pregnancy were included in this study; however, only 10 studies involving 5059 participants involved exposure to different antithyroid drugs exactly during pregnancy. Our results indicated that exposure to methimazole (MMI)/carbimazole (CMZ) only during pregnancy significantly increased the risk of neonatal congenital malformations compared to no antithyroid drug exposure (OR 1.88; 95%CI 1.33 to 2.65; P = 0.0004). No differences were observed between propylthiouracil (PTU) exposure and no antithyroid drug exposure only during pregnancy (OR 0.81; 95%CI 0.58 to 1.15; P = 0.24). Exposure to MMI/CMZ only during pregnancy significantly increased the risk of neonatal congenital malformations compared to that associated with exposure to PTU (OR 1.90; 95%CI 1.30 to 2.78; P = 0.001). Conclusion For pregnant women with hyperthyroidism, exposure to MMI/CMZ significantly increased the incidence of neonatal congenital malformations compared to exposure to PTU and no antithyroid drug exposure; however, no differences were observed between PTU exposure and no antithyroid drug exposure. PMID:28671971

  9. Effects of methimazole and propylthiouracil exposure during pregnancy on the risk of neonatal congenital malformations: A meta-analysis.

    Directory of Open Access Journals (Sweden)

    Rongjing Song

    Full Text Available The aim of this study was to determine the effect of exposure to different antithyroid drugs during pregnancy on the incidence of neonatal congenital malformations.A meta-analysis was performed to compare the incidence of neonatal congenital malformations after exposure to different antithyroid drugs during pregnancy. Twelve studies that met the inclusion criteria were included in this meta-analysis. PubMed, Embase, and CENTRAL databases were searched from inception until January 2017. Study designs included case-control studies, prospective cohort studies, and retrospective cohort studies.Twelve studies involving 8028 participants with exposure to different antithyroid drugs during pregnancy were included in this study; however, only 10 studies involving 5059 participants involved exposure to different antithyroid drugs exactly during pregnancy. Our results indicated that exposure to methimazole (MMI/carbimazole (CMZ only during pregnancy significantly increased the risk of neonatal congenital malformations compared to no antithyroid drug exposure (OR 1.88; 95%CI 1.33 to 2.65; P = 0.0004. No differences were observed between propylthiouracil (PTU exposure and no antithyroid drug exposure only during pregnancy (OR 0.81; 95%CI 0.58 to 1.15; P = 0.24. Exposure to MMI/CMZ only during pregnancy significantly increased the risk of neonatal congenital malformations compared to that associated with exposure to PTU (OR 1.90; 95%CI 1.30 to 2.78; P = 0.001.For pregnant women with hyperthyroidism, exposure to MMI/CMZ significantly increased the incidence of neonatal congenital malformations compared to exposure to PTU and no antithyroid drug exposure; however, no differences were observed between PTU exposure and no antithyroid drug exposure.

  10. Jovian atmospheres

    International Nuclear Information System (INIS)

    Allison, M.; Travis, L.D.

    1986-10-01

    A conference on the atmosphere of Jupiter produced papers in the areas of thermal and ortho-para hydrogen structure, clouds and chemistry, atmospheric structure, global dynamics, synoptic features and processes, atmospheric dynamics, and future spaceflight opportunities. A session on the atmospheres of Uranus and Neptune was included, and the atmosphere of Saturn was discussed in several papers

  11. Analysis of medical occupational exposure to ionizing radiation on Taiwan during past two decades

    International Nuclear Information System (INIS)

    Weng, P.-S.; Li, S.-Y.

    1980-01-01

    From the time of inception of the centralized laboratory for personnel dosimetry service operated by the National Tsing Hua University on Taiwan of the Republic of China in 1960 till 1979 the data obtained was analyzed to find the yearly occupational exposure to ionizing radiation. During the 20 year monitoring period, analysis was performed with reference to (1) medical occupational exposure, (2) maximum and average yearly dose-equivalent, (3) range of dose-equivalent, (4) percentage of maximum permissible dose-equivalent, (5) number of workers, including sex and age, (6) detailed quarterly analysis for the years 1977 to 1979, (7) types of radiation sources, and (8) estimation of the genetically significant dose-equivalent. (H.K.)

  12. Information Content Analysis for Selection of Optimal JWST  Observing Modes for Transiting Exoplanet Atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Batalha, Natasha E. [Department of Astronomy and Astrophysics, Pennsylvania State University, State College, PA 16802 (United States); Line, M. R., E-mail: neb149@psu.edu [School of Earth and Space Exploration, Arizona State University, Phoenix, AZ 85282 (United States)

    2017-04-01

    The James Webb Space Telescope ( JWST ) is nearing its launch date of 2018, and is expected to revolutionize our knowledge of exoplanet atmospheres. In order to specifically identify which observing modes will be most useful for characterizing a diverse range of exoplanetary atmospheres, we use an information content (IC) based approach commonly used in the studies of solar system atmospheres. We develop a system based upon these IC methods to trace the instrumental and atmospheric model phase space in order to identify which observing modes are best suited for particular classes of planets, focusing on transmission spectra. Specifically, the atmospheric parameter space we cover is T  = 600–1800 K, C/O = 0.55–1, [M/H] = 1–100 × Solar for an R  = 1.39 R{sub J}, M  = 0.59 M{sub J} planet orbiting a WASP-62-like star. We also explore the influence of a simplified opaque gray cloud on the IC. We find that obtaining broader wavelength coverage over multiple modes is preferred over higher precision in a single mode given the same amount of observing time. Regardless of the planet temperature and composition, the best modes for constraining terminator temperatures, C/O ratios, and metallicity are NIRISS SOSS+NIRSpec G395. If the target’s host star is dim enough such that the NIRSpec prism is applicable, then it can be used instead of NIRISS SOSS+NIRSpec G395. Lastly, observations that use more than two modes should be carefully analyzed because sometimes the addition of a third mode results in no gain of information. In these cases, higher precision in the original two modes is favorable.

  13. Atmospheric dispersion modeling and radiological safety analysis for a hypothetical accident of Ghana Research Reactor -1 (GHARR-1)

    International Nuclear Information System (INIS)

    Lunguya, J. M.

    2013-06-01

    This work presents the environmental impact analysis of some selected radionuclides released from the Ghana Research Reactor- 1 (GHARR-1) after a hypothetical postulated accidents scenario. The source term was identified and generated from an inventory of radioisotopes released during the accident. Atmospheric transport model was then applied to calculate the total effective dose and how it would be distributed to different organs of the human body as a function of distance downwind. All accident scenarios were selected from GHARR-1 Safety Analysis Report. After the source term was identified the MCNPX code was used to perform the core burnup/depletion analysis. The assumption was made that the activities were released to the atmosphere under a horse design basis accident scenario. The gaussian dose calculation method was applied, coded in Hotspot, a Healthy Physics computer code. This served as the computational tool to perform the atmospheric dispersion modeling and was used to calculate radionuclide concentration at downwind location. Based upon predominant meteorological conditions at the site, the adopted strategy was to use site-specific meteorological data and dispersion modeling to analyze the hypothetical release to the environment of radionuclides and evaluate to what extent such a release may have radiological effects on the public. Final data were processed and presented as Total Effective Dose Equivalent as a function of time and distance of deposition. The results indicate that all the values of Effective dose obtained are far below the regulatory limits, making the use of the reactor safe, even in the case of worst accident scenario where all the fission products were released into the atmosphere. (au)

  14. Personal Exposure to Mixtures of Volatile Organic Compounds: Modeling and Further Analysis of the RIOPA Data

    Science.gov (United States)

    Batterman, Stuart; Su, Feng-Chiao; Li, Shi; Mukherjee, Bhramar; Jia, Chunrong

    2015-01-01

    known to affect VOC exposures, many personal, environmental, and socioeconomic determinants remain to be identified, and the significance and applicability of the determinants reported in the literature are uncertain. To help answer these unresolved questions and overcome limitations of previous analyses, this project used several novel and powerful statistical modeling and analysis techniques and two large data sets. The overall objectives of this project were (1) to identify and characterize exposure distributions (including extreme values), (2) evaluate mixtures (including dependencies), and (3) identify determinants of VOC exposure. METHODS VOC data were drawn from two large data sets: the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study (1999–2001) and the National Health and Nutrition Examination Survey (NHANES; 1999–2000). The RIOPA study used a convenience sample to collect outdoor, indoor, and personal exposure measurements in three cities (Elizabeth, NJ; Houston, TX; Los Angeles, CA). In each city, approximately 100 households with adults and children who did not smoke were sampled twice for 18 VOCs. In addition, information about 500 variables associated with exposure was collected. The NHANES used a nationally representative sample and included personal VOC measurements for 851 participants. NHANES sampled 10 VOCs in common with RIOPA. Both studies used similar sampling methods and study periods. Specific Aim 1 To estimate and model extreme value exposures, extreme value distribution models were fitted to the top 10% and 5% of VOC exposures. Health risks were estimated for individual VOCs and for three VOC mixtures. Simulated extreme value data sets, generated for each VOC and for fitted extreme value and lognormal distributions, were compared with measured concentrations (RIOPA observations) to evaluate each model’s goodness of fit. Mixture distributions were fitted with the conventional finite mixture of normal distributions and the

  15. PREMOR: a point reactor exposure model computer code for survey analysis of power plant performance

    International Nuclear Information System (INIS)

    Vondy, D.R.

    1979-10-01

    The PREMOR computer code was written to exploit a simple, two-group point nuclear reactor power plant model for survey analysis. Up to thirteen actinides, fourteen fission products, and one lumped absorber nuclide density are followed over a reactor history. Successive feed batches are accounted for with provision for from one to twenty batches resident. The effect of exposure of each of the batches to the same neutron flux is determined

  16. PREMOR: a point reactor exposure model computer code for survey analysis of power plant performance

    Energy Technology Data Exchange (ETDEWEB)

    Vondy, D.R.

    1979-10-01

    The PREMOR computer code was written to exploit a simple, two-group point nuclear reactor power plant model for survey analysis. Up to thirteen actinides, fourteen fission products, and one lumped absorber nuclide density are followed over a reactor history. Successive feed batches are accounted for with provision for from one to twenty batches resident. The effect of exposure of each of the batches to the same neutron flux is determined.

  17. Exchange Rate Exposure and Its Determinants: A Firm and Industry Analysis of the UK Companies

    OpenAIRE

    He, Jiao

    2010-01-01

    This study assesses whether the unexpected exchange rate movements volatilize the UK firms’ stock return based on the firm- and industry-level analysis, and examines whether the magnitude of the exchange rate exposure is determined by the firm-specific factors. Using a sample of 244 UK companies listed in the FTSE 350 during the test period between December 1999 and December 2009, the result documents that the exchange rate fluctuation does affect the firm value. Among the five introduced ex...

  18. Vulnerability of Thai rice production to simultaneous climate and socioeconomic changes: a double exposure analysis

    Science.gov (United States)

    Sangpenchan, R.

    2011-12-01

    This research explores the vulnerability of Thai rice production to simultaneous exposure by climate and socioeconomic change -- so-called "double exposure." Both processes influence Thailand's rice production system, but the vulnerabilities associated with their interactions are unknown. To understand this double exposure, I adopts a mixed-method, qualitative-quantitative analytical approach consisting of three phases of analysis involving a Vulnerability Scoping Diagram, a Principal Component Analysis, and the EPIC crop model using proxy datasets collected from secondary data sources at provincial scales.The first and second phases identify key variables representing each of the three dimensions of vulnerability -- exposure, sensitivity, and adaptive capacity indicating that the greatest vulnerability in the rice production system occurs in households and areas with high exposure to climate change, high sensitivity to climate and socioeconomic stress, and low adaptive capacity. In the third phase, the EPIC crop model simulates rice yields associated with future climate change projected by CSIRO and MIROC climate models. Climate change-only scenarios project the decrease in yields by 10% from the current productivity during 2016-2025 and 30% during 2045-2054. Scenarios applying both climate change and improved technology and management practices show that a 50% increase in rice production is possible, but requires strong collaboration between sectors to advance agricultural research and technology and requires strong adaptive capacity in the rice production system characterized by well-developed social capital, social networks, financial capacity, and infrastructure and household mobility at the local scale. The vulnerability assessment and climate and crop adaptation simulations used here provide useful information to decision makers developing vulnerability reduction plans in the face of concurrent climate and socioeconomic change.

  19. Lateral Epicondylitis and Physical Exposure at Work? A Review of Prospective Studies and Meta-Analysis.

    Science.gov (United States)

    Descatha, Alexis; Albo, Francesco; Leclerc, Annette; Carton, Matthieu; Godeau, Diane; Roquelaure, Yves; Petit, Audrey; Aublet-Cuvelier, Agnès

    2016-11-01

    In view of recent published studies, a meta-analysis was undertaken on prospective studies in order to assess any association between lateral epicondylitis and physical exposure at work. Using the key words "lateral epicondylitis" AND "occupational" AND ("cohort" OR "longitudinal," OR "incidence") without limitations on the language or year of publication, original prospective studies were selected from 4 databases (PubMed, Scopus, Web of Science, and Base de Données de Santé Publique) after 2 rounds (valid design, valid association reported, and valid work exposure). Relevant associations between physical exposure at work and incident lateral epicondylitis were extracted from the articles, and a meta-risk was calculated using the generic variance approach (meta-odds ratios [meta-ORs]). From 2001 to 2014, 5 prospective studies were included. Among 6,922 included subjects (and 3,449 who were followed), 256 cases of incident lateral epicondylitis were diagnosed 2.5-6 years after baseline. All the published studies found a significant estimation of relative risk for a positive association between combined biomechanic exposure involving the wrist and/or elbow and incidence of lateral epicondylitis. The overall meta-OR was 2.6 (95% confidence interval 1.9-3.5), with a low heterogeneity (Q = 1.4, P > 0.05). Funnel plots and Egger's test did not suggest major publication bias. The results of this meta-analysis strongly support the hypothesis of an association between biomechanic exposure involving the wrist and/or elbow at work and incidence of lateral epicondylitis. © 2016, American College of Rheumatology.

  20. Airborne asbestos exposures associated with gasket and packing replacement: a simulation study and meta-analysis.

    Science.gov (United States)

    Madl, Amy K; Hollins, Dana M; Devlin, Kathryn D; Donovan, Ellen P; Dopart, Pamela J; Scott, Paul K; Perez, Angela L

    2014-08-01

    Exposures to airborne asbestos during the removal and installation of internal gaskets and packing associated with a valve overhaul were characterized and compared to published data according to different variables (e.g., product, equipment, task, tool, setting, duration). Personal breathing zone and area samples were collected during twelve events simulating gasket and packing replacement, clean-up and clothing handling. These samples were analyzed using PCM and TEM methods and PCM-equivalent (PCME) airborne asbestos concentrations were calculated. A meta-analysis was performed to compare these data with airborne asbestos concentrations measured in other studies involving gaskets and packing. Short-term mechanic and assistant airborne asbestos concentrations during valve work averaged 0.013f/cc and 0.008f/cc (PCME), respectively. Area samples averaged 0.008f/cc, 0.005f/cc, and 0.003f/cc (PCME) for center, bystander, and remote background, respectively. Assuming a tradesman conservatively performs 1-3 gasket and/or packing replacements daily, an average 8-h TWA was estimated to be 0.002-0.010f/cc (PCME). Combining these results in a meta-analysis of the published exposure data showed that the majority of airborne asbestos exposures during work with gaskets and packing fall within a consistent and low range. Significant differences in airborne concentrations were observed between power versus manual tools and removal versus installation tasks. Airborne asbestos concentrations resulting from gasket and packing work during a valve overhaul are consistent with historical exposure data on replacement of asbestos-containing gasket and packing materials involving multiple variables and, in nearly all plausible scenarios, result in average airborne asbestos concentrations below contemporaneous occupational exposure limits for asbestos. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Inverse problems using ANN in long range atmospheric dispersion with signature analysis picked scattered numerical sensors from CFD

    International Nuclear Information System (INIS)

    Sharma, Pavan K.; Gera, B.; Ghosh, A.K.; Kushwaha, H.S.

    2010-01-01

    Scalar dispersion in the atmosphere is an important area wherein different approaches are followed in development of good analytical model. The analyses based on Computational Fluid Dynamics (CFD) codes offer an opportunity of model development based on first principles of physics and hence such models have an edge over the existing models. Both forward and backward calculation methods are being developed for atmospheric dispersion around NPPs at BARC Forward modeling methods, which describe the atmospheric transport from sources to receptors, use forward-running transport and dispersion models or computational fluid dynamics models which are run many times, and the resulting dispersion field is compared to observations from multiple sensors. Backward or inverse modeling methods use only one model run in the reverse direction from the receptors to estimate the upwind sources. Inverse modeling methods include adjoint and tangent linear models, Kalman filters, and variational data assimilation, and neural network. The present paper is aimed at developing a new approach where the identified specific signatures at receptor points form the basis for source estimation or inversions. This approach is expected to reduce the large transient data sets to reduced and meaningful data sets. In fact this reduces the inherently transient data set into a time independent mean data set. Forward computation were carried out with CFD code for various case to generate a large set of data to train the ANN. Specific signature analysis was carried out to find the parameters of interest for ANN training like peak concentration, time to reach peak concentration and time to fall, the ANN was trained with data and source strength and location were predicted from ANN. Inverse problem was performed using ANN approach in long range atmospheric dispersion. An illustration of application of CFD code for atmospheric dispersion studies for a hypothetical case is also included in the paper. (author)

  2. Bivariate Left-Censored Bayesian Model for Predicting Exposure: Preliminary Analysis of Worker Exposure during the Deepwater Horizon Oil Spill.

    Science.gov (United States)

    Groth, Caroline; Banerjee, Sudipto; Ramachandran, Gurumurthy; Stenzel, Mark R; Sandler, Dale P; Blair, Aaron; Engel, Lawrence S; Kwok, Richard K; Stewart, Patricia A

    2017-01-01

    In April 2010, the Deepwater Horizon oil rig caught fire and exploded, releasing almost 5 million barrels of oil into the Gulf of Mexico over the ensuing 3 months. Thousands of oil spill workers participated in the spill response and clean-up efforts. The GuLF STUDY being conducted by the National Institute of Environmental Health Sciences is an epidemiological study to investigate potential adverse health effects among these oil spill clean-up workers. Many volatile chemicals were released from the oil into the air, including total hydrocarbons (THC), which is a composite of the volatile components of oil including benzene, toluene, ethylbenzene, xylene, and hexane (BTEXH). Our goal is to estimate exposure levels to these toxic chemicals for groups of oil spill workers in the study (hereafter called exposure groups, EGs) with likely comparable exposure distributions. A large number of air measurements were collected, but many EGs are characterized by datasets with a large percentage of censored measurements (below the analytic methods' limits of detection) and/or a limited number of measurements. We use THC for which there was less censoring to develop predictive linear models for specific BTEXH air exposures with higher degrees of censoring. We present a novel Bayesian hierarchical linear model that allows us to predict, for different EGs simultaneously, exposure levels of a second chemical while accounting for censoring in both THC and the chemical of interest. We illustrate the methodology by estimating exposure levels for several EGs on the Development Driller III, a rig vessel charged with drilling one of the relief wells. The model provided credible estimates in this example for geometric means, arithmetic means, variances, correlations, and regression coefficients for each group. This approach should be considered when estimating exposures in situations when multiple chemicals are correlated and have varying degrees of censoring. © The Author 2017

  3. Differentiation between exposures to high or low ionizing radiation by means of Triage type analysis

    International Nuclear Information System (INIS)

    Guerrero C, C.; Arceo M, C.; Martinez A, J.; Cortina R, E.

    2016-09-01

    According to a culture of disaster prevention, in this case a radiological emergency, in which a large number of people are exposed to high doses of ionizing radiation, is necessary to make urgent decisions regarding the appropriate treatment, which for each case is required. In this regard, chromosomal analysis may provide additional information to that obtained from clinical observations confirming cases that suffered severe partial exposure and at the same time discriminating against false positives attributable to previous infections or hysterical behavior. The ionizing radiation causes different types of aberrations in the chromosomes, but one of the most characteristic is dicentric. The analysis of these in lymphocytes is a good indicator of the degree of exposure, because apart from being easily recognizable, the basal frequency in the population is low (1 x 10 3 cells) and increases in proportion to the dose. In order to establish the exposure dose, is usually necessary to analyze 1000 cells, a procedure that in an emergency, is very slow since is necessary to make rapid decisions to apply the appropriate treatment to the patient. The results of this intercalibration exercise demonstrate that the analysis of 20, 30 or 50 metaphases is sufficient to separate the cases of overexposure from the non-radio exposed ones and to the first ones by gravity category. (Author)

  4. Combined analysis of job and task benzene air exposures among workers at four US refinery operations.

    Science.gov (United States)

    Burns, Amanda; Shin, Jennifer Mi; Unice, Ken M; Gaffney, Shannon H; Kreider, Marisa L; Gelatt, Richard H; Panko, Julie M

    2017-03-01

    Workplace air samples analyzed for benzene at four US refineries from 1976 to 2007 were pooled into a single dataset to characterize similarities and differences between job titles, tasks and refineries, and to provide a robust dataset for exposure reconstruction. Approximately 12,000 non-task (>180 min) personal samples associated with 50 job titles and 4000 task (job titles and task codes across all four refineries, and (5) our analysis of variance (ANOVA) of the distribution of benzene air concentrations for select jobs/tasks across all four refineries. The jobs and tasks most frequently sampled included those with highest potential contact with refinery product streams containing benzene, which reflected the targeted sampling approach utilized by the facility industrial hygienists. Task and non-task data were analyzed to identify and account for significant differences within job-area, task-job, and task-area categories. This analysis demonstrated that in general, areas with benzene containing process streams were associated with greater benzene air concentrations compared to areas with process streams containing little to no benzene. For several job titles and tasks analyzed, there was a statistically significant decrease in benzene air concentration after 1990. This study provides a job and task-focused analysis of occupational exposure to benzene during refinery operations, and it should be useful for reconstructing refinery workers' exposures to benzene over the past 30 years.

  5. Analysis of air-, moisture- and solvent-sensitive chemical compounds by mass spectrometry using an inert atmospheric pressure solids analysis probe.

    Science.gov (United States)

    Mosely, Jackie A; Stokes, Peter; Parker, David; Dyer, Philip W; Messinis, Antonis M

    2018-02-01

    A novel method has been developed that enables chemical compounds to be transferred from an inert atmosphere glove box and into the atmospheric pressure ion source of a mass spectrometer whilst retaining a controlled chemical environment. This innovative method is simple and cheap to implement on some commercially available mass spectrometers. We have termed this approach inert atmospheric pressure solids analysis probe ( iASAP) and demonstrate the benefit of this methodology for two air-/moisture-sensitive chemical compounds whose characterisation by mass spectrometry is now possible and easily achieved. The simplicity of the design means that moving between iASAP and standard ASAP is straightforward and quick, providing a highly flexible platform with rapid sample turnaround.

  6. An analysis of employee exposure to organic dust at large-scale composting facilities

    Science.gov (United States)

    Sykes, P.; Allen, J. A.; Wildsmith, J. D.; Jones, K. P.

    2009-02-01

    The occupational health implications from exposure to dust, endotoxin and 1-3 β Glucan at commercial composting sites are uncertain. This study aims to establish employee exposure levels to inhalable and respirable dust, endotoxin and 1-3 β Glucan during various operational practices in the composting process. Personal samples were collected and the inhalable and respirable dust fractions were determined by gravimetric analysis. Endotoxin concentrations were determined using a Limulus Amebocyte Lysate assay (LAL). 1-3 β Glucan levels were estimated using a specific blocking agent to establish the contribution that these compounds gave to the original endotoxin assay. Employees' exposure to dust was found to be generally lower than the levels stipulated in the Control of Substances Hazardous to Health Regulations (COSHH) 2002 (as amended), (median inhalable fraction 1.08 mg/m3, min 0.25 mg/m3 max 10.80 mg/m3, median respirable fraction 0.05 mg/m3, min 0.02 mg/m3, max 1.49 mg/m3). Determination of the biological component of the dust showed that employees' exposures to endotoxin were elevated (median 31.5 EU/m3, min 2.00 EU/m3, max 1741.78 EU/m3), particularly when waste was agitated (median 175.0 EU/m3, min 2.03 EU/m3, max 1741.78 EU/m3). Eight out of 32 (25%) of the personal exposure data for endotoxin exceeded the 200 EU/m3 temporary legal limit adopted in the Netherlands and thirteen out of 32 (40.6%) exceeded the suggested 50 EU/m3 guidance level suggested to protect workers from respiratory health effects. A significant correlation was observed between employee inhalable dust exposure and personal endotoxin concentration (r = 0.728, phealth risks associated with endotoxin exposure at composting sites. Employee exposure levels and dose-response disease mechanisms are not well understood at this present time. Consequently, in light of this uncertainty, it is recommended that a precautionary approach be adopted in managing the potential health risks associated

  7. Carbon Dioxide Information Analysis Center and World Data Center for Atmospheric Trace Gases, Fiscal Year 2002 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, R.M.

    2003-08-28

    The Carbon Dioxide Information Analysis Center (CDIAC), which includes the World Data Center (WDC) for Atmospheric Trace Gases, is the primary global change data and information analysis center of the U.S. Department of Energy (DOE). More than just an archive of data sets and publications, CDIAC has, since its inception in 1982, enhanced the value of its holdings through intensive quality assurance, documentation, and integration. Whereas many traditional data centers are discipline-based (for example, meteorology or oceanography), CDIAC's scope includes potentially anything and everything that would be of value to users concerned with the greenhouse effect and global climate change, including atmospheric concentrations and atmospheric emissions of carbon dioxide (CO{sub 2}) and other radiatively active gases; the role of the terrestrial biosphere and the oceans in the biogeochemical cycles of greenhouse gases; long-term climate trends; the effects of elevated CO{sub 2} on vegetation; and the vulnerability of coastal areas to rising sea levels.

  8. Carbon Dioxide Information Analysis Center and World Data Center for Atmospheric Trace Gases Fiscal Year 2000 Annual Report; ANNUAL

    International Nuclear Information System (INIS)

    Cushman, R.M.

    2001-01-01

    The Carbon Dioxide Information Analysis Center (CDIAC), which includes the World Data Center (WDC) for Atmospheric Trace Gases, is the primary global change data and information analysis center of the U.S. Department of Energy (DOE). More than just an archive of data sets and publications, CDIAC has, since its inception in 1982, enhanced the value of its holdings through intensive quality assurance, documentation, and integration. Whereas many traditional data centers are discipline-based (for example, meteorology or oceanography), CDIAC's scope includes potentially anything and everything that would be of value to users concerned with the greenhouse effect and global climate change, including concentrations of carbon dioxide (CO(sub 2)) and other radiatively active gases in the atmosphere; the role of the terrestrial biosphere and the oceans in the biogeochemical cycles of greenhouse gases; emissions of CO(sub 2) and other trace gases to the atmosphere; long-term climate trends; the effects of elevated CO(sub 2) on vegetation; and the vulnerability of coastal areas to rising sea levels

  9. Carbon Dioxide Information Analysis Center and World Data Center for Atmospheric Trace Gases Fiscal Year 2000 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, R.M.

    2001-11-15

    The Carbon Dioxide Information Analysis Center (CDIAC), which includes the World Data Center (WDC) for Atmospheric Trace Gases, is the primary global change data and information analysis center of the U.S. Department of Energy (DOE). More than just an archive of data sets and publications, CDIAC has, since its inception in 1982, enhanced the value of its holdings through intensive quality assurance, documentation, and integration. Whereas many traditional data centers are discipline-based (for example, meteorology or oceanography), CDIAC's scope includes potentially anything and everything that would be of value to users concerned with the greenhouse effect and global climate change, including concentrations of carbon dioxide (CO{sub 2}) and other radiatively active gases in the atmosphere; the role of the terrestrial biosphere and the oceans in the biogeochemical cycles of greenhouse gases; emissions of CO{sub 2} and other trace gases to the atmosphere; long-term climate trends; the effects of elevated CO{sub 2} on vegetation; and the vulnerability of coastal areas to rising sea levels.

  10. A meta-analysis of the effects of exposure to microplastics on fish and aquatic invertebrates.

    Science.gov (United States)

    Foley, Carolyn J; Feiner, Zachary S; Malinich, Timothy D; Höök, Tomas O

    2018-08-01

    Microplastics are present in aquatic ecosystems the world over and may influence the feeding, growth, reproduction, and survival of freshwater and marine biota; however, the extent and magnitude of potential effects of microplastics on aquatic organisms is poorly understood. In the current study, we conducted a meta-analysis of published literature to examine impacts of exposure to microplastics on consumption (and feeding), growth, reproduction, and survival of fish and aquatic invertebrates. While we did observe within-taxa negative effects for all four categories of responses, many of the effects summarized in our study were neutral, indicating that the effects of exposure to microplastics are highly variable across taxa. The most consistent effect was a reduction in consumption of natural prey when microplastics were present. For some taxa, negative effects on growth, reproduction and even survival were also evident. Organisms that serve as prey to larger predators, e.g., zooplankton, may be particularly susceptible to negative impacts of exposure to microplastic pollution, with potential for ramifications throughout the food web. Future work should focus on whether microplastics may be affecting aquatic organisms more subtly, e.g., by influencing exposure to contaminants and pathogens, or by acting at a molecular level. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Maternal SSRI exposure increases the risk of autistic offspring: A meta-analysis and systematic review.

    Science.gov (United States)

    Andalib, S; Emamhadi, M R; Yousefzadeh-Chabok, S; Shakouri, S K; Høilund-Carlsen, P F; Vafaee, M S; Michel, T M

    2017-09-01

    Selective serotonin reuptake inhibitors (SSRIs) are the most common antidepressants used to preclude maternal pregnancy depression. There is a growing body of literature assessing the association of prenatal exposure to SSRIs with autism spectrum disorder (ASD). The present systematic review and meta-analysis reviewed the medical literature and pooled the results of the association of prenatal exposure to SSRIs with ASD. Published investigations in English by June 2016 with keywords of selective serotonin reuptake inhibitors, SSRI, autism spectrum disorder, ASD, pregnancy, childhood, children, neurodevelopment were identified using databases PubMed and PMC, MEDLINE, EMBASE, SCOPUS, and Google Scholar. Cochran's Q statistic-value (Q), degree of freedom (df), and I 2 indices (variation in odds ratio [OR] attributable to heterogeneity) were calculated to analyze the risk of heterogeneity of the within- and between-study variability. Pooled odds ratio (OR) and 95% confidence interval (CI) were reported by a Mantel-Haenszel test. There was a non-significant heterogeneity for the included studies ([Q=3.61, df=6, P=0.730], I 2 =0%). The pooled results showed a significant association between prenatal SSRI exposure and ASD (OR=1.82, 95% CI=1.59-2.10, Z=8.49, P=0.00). The evidence from the present study suggests that prenatal exposure to SSRIs is associated with a higher risk of ASD. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Exposure to violent video games and aggression in German adolescents: a longitudinal analysis.

    Science.gov (United States)

    Möller, Ingrid; Krahé, Barbara

    2009-01-01

    The relationship between exposure to violent electronic games and aggressive cognitions and behavior was examined in a longitudinal study. A total of 295 German adolescents completed the measures of violent video game usage, endorsement of aggressive norms, hostile attribution bias, and physical as well as indirect/relational aggression cross-sectionally, and a subsample of N=143 was measured again 30 months later. Cross-sectional results at T1 showed a direct relationship between violent game usage and aggressive norms, and an indirect link to hostile attribution bias through aggressive norms. In combination, exposure to game violence, normative beliefs, and hostile attribution bias predicted physical and indirect/relational aggression. Longitudinal analyses using path analysis showed that violence exposure at T1 predicted physical (but not indirect/relational) aggression 30 months later, whereas aggression at T1 was unrelated to later video game use. Exposure to violent games at T1 influenced physical (but not indirect/relational) aggression at T2 via an increase of aggressive norms and hostile attribution bias. The findings are discussed in relation to social-cognitive explanations of long-term effects of media violence on aggression. Copyright 2008 Wiley-Liss, Inc.

  13. Comparative analysis of atmosphere temperature variability for Northern Eurasia based on the Reanalysis and in-situ observed data

    Science.gov (United States)

    Shulgina, T.; Genina, E.; Gordov, E.; Nikitchuk, K.

    2009-04-01

    At present numerous data archives which include meteorological observations as well as climate processes modeling data are available for Earth Science specialists. Methods of mathematical statistics are widely used for their processing and analysis. In many cases they represent the only way of quantitative assessment of the meteorological and climatic information. Unified set of analysis methods allows us to compare climatic characteristics calculated on the basis of different datasets with the purpose of performing more detailed analysis of climate dynamics for both regional and global levels. The report presents the results of comparative analysis of atmosphere temperature behavior for the Northern Eurasia territory for the period from 1979 to 2004 based on the NCEP/NCAR Reanalysis, NCEP/DOE Reanalysis AMIP II, JMA/CRIEPI JRA-25 Reanalysis, ECMWF ERA-40 Reanalysis data and observation data obtained from meteorological stations of the former Soviet Union. Statistical processing of atmosphere temperature data included analysis of time series homogeneity of climate indices approved by WMO, such as "Number of frost days", "Number of summer days", "Number of icing days", "Number of tropical nights", etc. by means of parametric methods of mathematical statistics (Fisher and Student tests). That allowed conducting comprehensive research of spatio-temporal features of the atmosphere temperature. Analysis of the atmosphere temperature dynamics revealed inhomogeneity of the data obtained for large observation intervals. Particularly, analysis performed for the period 1979 - 2004 showed the significant increase of the number of frost and icing days approximately by 1 day for every 2 years and decrease roughly by 1 day for 2 years for the number of summer days. Also it should be mentioned that the growth period mean temperature have increased by 1.5 - 2° C for the time period being considered. The usage of different Reanalysis datasets in conjunction with in-situ observed

  14. A Multipixel Time Series Analysis Method Accounting for Ground Motion, Atmospheric Noise, and Orbital Errors

    Science.gov (United States)

    Jolivet, R.; Simons, M.

    2018-02-01

    Interferometric synthetic aperture radar time series methods aim to reconstruct time-dependent ground displacements over large areas from sets of interferograms in order to detect transient, periodic, or small-amplitude deformation. Because of computational limitations, most existing methods consider each pixel independently, ignoring important spatial covariances between observations. We describe a framework to reconstruct time series of ground deformation while considering all pixels simultaneously, allowing us to account for spatial covariances, imprecise orbits, and residual atmospheric perturbations. We describe spatial covariances by an exponential decay function dependent of pixel-to-pixel distance. We approximate the impact of imprecise orbit information and residual long-wavelength atmosphere as a low-order polynomial function. Tests on synthetic data illustrate the importance of incorporating full covariances between pixels in order to avoid biased parameter reconstruction. An example of application to the northern Chilean subduction zone highlights the potential of this method.

  15. Wood dust exposure and lung cancer risk: a meta-analysis.

    Science.gov (United States)

    Hancock, David G; Langley, Mary E; Chia, Kwan Leung; Woodman, Richard J; Shanahan, E Michael

    2015-12-01

    Occupational lung cancers represent a major health burden due to their increasing prevalence and poor long-term outcomes. While wood dust is a confirmed human carcinogen, its association with lung cancer remains unclear due to inconsistent findings in the literature. We aimed to clarify this association using meta-analysis. We performed a search of 10 databases to identify studies published until June 2014. We assessed the lung cancer risk associated with wood dust exposure as the primary outcome and with wood dust-related occupations as a secondary outcome. Random-effects models were used to pool summary risk estimates. 85 publications were included in the meta-analysis. A significantly increased risk for developing lung cancer was observed among studies that directly assessed wood dust exposure (RR 1.21, 95% CI 1.05 to 1.39, n=33) and that assessed wood dust-related occupations (RR 1.15, 95% CI 1.07 to 1.23, n=59). In contrast, a reduced risk for lung cancer was observed among wood dust (RR 0.63, 95% CI 0.39 to 0.99, n=5) and occupation (RR 0.96, 95% CI 0.95 to 0.98, n=1) studies originating in Nordic countries, where softwood dust is the primary exposure. These results were independent of the presence of adjustment for smoking and exposure classification methods. Only minor differences in risk between the histological subtypes were identified. This meta-analysis provides strong evidence for an association between wood dust and lung cancer, which is critically influenced by the geographic region of the study. The reasons for this region-specific effect estimates remain to be clarified, but may suggest a differential effect for hardwood and softwood dusts. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  16. Characteristics and outcomes of e-cigarette exposure incidents reported to 10 European Poison Centers: a retrospective data analysis

    OpenAIRE

    Vardavas, Constantine I.; Girvalaki, Charis; Filippidis, Filippos T; Oder, Mare; Kastanje, Ruth; de Vries, Irma; Scholtens, Lies; Annas, Anita; Plackova, Silvia; Turk, Rajka; Gruzdyte, Laima; Rato, F?tima; Genser, Dieter; Schiel, Helmut; Bal?zs, Andrea

    2017-01-01

    BACKGROUND: The use of e-cigarettes has increased during the past few years. Exposure to e-cigarette liquids, whether intentional or accidental, may lead to adverse events our aim was to assess factors associated with e-cigarette exposures across European Union Member States (EU MS). METHODS: A retrospective analysis of exposures associated with e-cigarettes reported to national poison centers was performed covering incidents from 2012 to March 2015 from 10 EU MS. De-identified and anonymous ...

  17. Model analysis of the effects of atmospheric drivers on storage water use in Scots pine

    Directory of Open Access Journals (Sweden)

    H. Verbeeck

    2007-08-01

    Full Text Available Storage water use is an indirect consequence of the interplay between different meteorological drivers through their effect on water flow and water potential in trees. We studied these microclimatic drivers of storage water use in Scots pine (Pinus sylvestris L. growing in a temperate climate. The storage water use was modeled using the ANAFORE model, integrating a dynamic water flow and – storage model with a process-based transpiration model. The model was calibrated and validated with sap flow measurements for the growing season of 2000 (26 May–18 October.

    Because there was no severe soil drought during the study period, we were able to study atmospheric effects. Incoming radiation and vapour pressure deficit (VPD were the main atmospheric drivers of storage water use. The general trends of sap flow and storage water use are similar, and follow more or less the pattern of incoming radiation. Nevertheless, considerable differences in the day-to-day pattern of sap flow and storage water use were observed. VPD was determined to be one of the main drivers of these differences. During dry atmospheric conditions (high VPD storage water use was reduced. This reduction was higher than the reduction in measured sap flow. Our results suggest that the trees did not rely more on storage water during periods of atmospheric drought, without severe soil drought. The daily minimum tree water content was lower in periods of high VPD, but the reserves were not completely depleted after the first day of high VPD, due to refilling during the night.

    Nevertheless, the tree water content deficit was a third important factor influencing storage water use. When storage compartments were depleted beyond a threshold, storage water use was limited due to the low water potential in the storage compartments. The maximum relative contribution of storage water to daily transpiration was also constrained by an increasing tree water content

  18. Uniform Atmospheric Retrieval Analysis of Ultracool Dwarfs. II. Properties of 11 T dwarfs

    Energy Technology Data Exchange (ETDEWEB)

    Line, Michael R. [School of Earth and Space Exploration, Arizona State University, Tempe AZ 85287 (United States); Marley, Mark S.; Freedman, Richard [NASA Ames Research Center, Mail Stop 245-3, Moffett Field, CA 94035 (United States); Liu, Michael C. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Burningham, Ben [Centre for Astrophysics Research, School of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); Morley, Caroline V. [Department of Astronomy, Harvard University, Cambridge, MA 02138 (United States); Hinkel, Natalie R. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Teske, Johanna [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Lupu, Roxana, E-mail: mrline@asu.edu [BAER Institute/NASA Ames Research Center, Mail Stop 245-3, Moffett Field, CA 94035 (United States)

    2017-10-20

    Brown dwarf spectra are rich in information revealing of the chemical and physical processes operating in their atmospheres. We apply a recently developed atmospheric retrieval tool to an ensemble of late-T dwarf (600–800 K) near-infrared (1–2.5 μ m) spectra. With these spectra we are able to directly constrain the molecular abundances for the first time of H{sub 2}O, CH{sub 4}, CO, CO{sub 2}, NH{sub 3}, H{sub 2}S, and Na+K, surface gravity, effective temperature, thermal structure, photometric radius, and cloud optical depths. We find that ammonia, water, methane, and the alkali metals are present and that their abundances are well constrained in all 11 objects. We find no significant trend in the water, methane, or ammonia abundances with temperature, but find a very strong (>25 σ ) decreasing trend in the alkali metal abundances with decreasing effective temperature, indicative of alkali rainout. As expected from previous work, we also find little evidence for optically thick clouds. With the methane and water abundances, we derive the intrinsic atmospheric metallicity and carbon-to-oxygen ratios. We find in our sample that metallicities are typically subsolar (−0.4 < [ M /H] < 0.1 dex) and carbon-to-oxygen ratios are somewhat supersolar (0.4 < C/O < 1.2), different than expectations from the local stellar population. We also find that the retrieved vertical thermal profiles are consistent with radiative equilibrium over the photospheric regions. Finally, we find that our retrieved effective temperatures are lower than previous inferences for some objects and that some of our radii are larger than expectations from evolutionary models, possibly indicative of unresolved binaries. This investigation and method represent a new and powerful paradigm for using spectra to determine the fundamental chemical and physical processes governing cool brown dwarf atmospheres.

  19. Summary of the Atmospheric Test Data (Film Scanning and Re-Analysis) Project at LLNL

    Energy Technology Data Exchange (ETDEWEB)

    Murray, S. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-03-21

    The goal of the Atmospheric Test Data (ATD) Project is to preserve and make better use of scientific-quality films that were taken during the era of above ground nuclear testing. The project is being done in collaboration with Los Alamos National Laboratory, which is the custodian of the films. Our primary points of contact at LANL have been Alan Carr, Carla Breiner, and Randy Drake.

  20. Analysis of insect triacylglycerols using liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Kofroňová, Edita; Cvačka, Josef; Jiroš, Pavel; Sýkora, D.; Valterová, Irena

    2009-01-01

    Roč. 111, č. 5 (2009), s. 519-525 ISSN 1438-7697 R&D Projects: GA AV ČR IAA4055403; GA MŠk 2B06007 Institutional research plan: CEZ:AV0Z40550506 Keywords : atmospheric pressure chemical ionization * bumblebees * fat body * NARP-HPLC Subject RIV: CC - Organic Chemistry Impact factor: 1.831, year: 2009

  1. What are the most fire-dangerous atmospheric circulations in the Eastern-Mediterranean? Analysis of the synoptic wildfire climatology.

    Science.gov (United States)

    Paschalidou, A K; Kassomenos, P A

    2016-01-01

    Wildfire management is closely linked to robust forecasts of changes in wildfire risk related to meteorological conditions. This link can be bridged either through fire weather indices or through statistical techniques that directly relate atmospheric patterns to wildfire activity. In the present work the COST-733 classification schemes are applied in order to link wildfires in Greece with synoptic circulation patterns. The analysis reveals that the majority of wildfire events can be explained by a small number of specific synoptic circulations, hence reflecting the synoptic climatology of wildfires. All 8 classification schemes used, prove that the most fire-dangerous conditions in Greece are characterized by a combination of high atmospheric pressure systems located N to NW of Greece, coupled with lower pressures located over the very Eastern part of the Mediterranean, an atmospheric pressure pattern closely linked to the local Etesian winds over the Aegean Sea. During these events, the atmospheric pressure has been reported to be anomalously high, while anomalously low 500hPa geopotential heights and negative total water column anomalies were also observed. Among the various classification schemes used, the 2 Principal Component Analysis-based classifications, namely the PCT and the PXE, as well as the Leader Algorithm classification LND proved to be the best options, in terms of being capable to isolate the vast amount of fire events in a small number of classes with increased frequency of occurrence. It is estimated that these 3 schemes, in combination with medium-range to seasonal climate forecasts, could be used by wildfire risk managers to provide increased wildfire prediction accuracy. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Analysis of atmospheric pressure and temperature effects on cosmic ray measurements

    Science.gov (United States)

    de MendonçA, R. R. S.; Raulin, J.-P.; Echer, E.; Makhmutov, V. S.; Fernandez, G.

    2013-04-01

    In this paper, we analyze atmospheric pressure and temperature effects on the records of the cosmic ray detector CARPET. This detector has monitored secondary cosmic ray intensity since 2006 at Complejo Astronómico El Leoncito (San Juan, Argentina, 31°S, 69°W, 2550 m over sea level) where the geomagnetic rigidity cutoff, Rc, is ~9.8 GV. From the correlation between atmospheric pressure deviations and relative cosmic ray variations, we obtain a barometric coefficient of -0.44 ± 0.01 %/hPa. Once the data are corrected for atmospheric pressure, they are used to analyze temperature effects using four methods. Three methods are based on the surface temperature and the temperature at the altitude of maximum production of secondary cosmic rays. The fourth method, the integral method, takes into account the temperature height profile between 14 and 111 km above Complejo Astronómico El Leoncito. The results obtained from these four methods are compared on different time scales from seasonal time variations to scales related to the solar activity cycle. Our conclusion is that the integral method leads to better results to remove the temperature effect of the cosmic ray intensity observed at ground level.

  3. Automatic parameterization and analysis of stellar atmospheres: a study of the DA white dwarfs

    International Nuclear Information System (INIS)

    McMahan, R.K. Jr.

    1986-01-01

    A method for automatically calculating atmospheric parameters of hydrogen-rich degenerate stars from low resolution spectra is advanced and then applied to the spectra of 53 DA white dwarfs. All data were taken using the Mark II spectrograph on the McGraw-Hill 1.3 m telescope and cover the spectral range λλ4100-7000 at a resolution of eight Angstroms. The model grid was generated at Dartmouth using the atmosphere code LUCIFER; it contained over 275 synthetic spectra extending from 6000 to 100,000 K in effective temperature and 7.4-9.3 in log g. A new value for the width of the DA mass distribution was achieved using the techniques presented here. Accuracies in the atmospheric parameters greater than twice those previously published were obtained. These results place strict constraints on the magnitude of mass loss in stars in the red giant phase, as well as in the mechanisms responsible for the loss

  4. Analysis of reaction products formed in the gas phase reaction of E,E-2,4-hexadienal with atmospheric oxidants: Reaction mechanisms and atmospheric implications

    Science.gov (United States)

    Colmenar, I.; Martin, P.; Cabañas, B.; Salgado, S.; Martinez, E.

    2018-03-01

    An analysis of reaction products for the reaction of E,E-2,4-hexadienal with chlorine atoms (Cl) and OH and NO3 radicals has been carried out at the first time with the aim of obtaining a better understanding of the tropospheric reactivity of α,β-unsaturated carbonyl compounds. Fourier Transform Infrared (FTIR) spectroscopy and Gas Chromatography-Mass Spectrometry with a Time of Flight detector (GC-TOFMS) were used to carry out the qualitative and/or quantitative analyses. Reaction products in gas and particulate phase were observed from the reactions of E,E-2,4- hexadienal with all oxidants. E/Z-Butenedial and maleic anhydride were the main products identified in gas phase. E-butenedial calculated molar yield ranging from 4 to 10%. A significant amount of multifunctional compounds (chloro and hydroxy carbonyls) was identified. These compounds could be formed in particulate phase explaining the ∼90% of unaccounted carbon in gas phase. The reaction with Cl atoms in the presence of NOx with a long reaction time gave Peroxy Acetyl Nitrate (PAN) as an additional product, which is known for being an important specie in the generation of the photochemical smog. Nitrated compounds were the major organic products from the reaction with the NO3 radical. Based on the identified products, the reaction mechanisms have been proposed. In these mechanisms a double bond addition of the atmospheric oxidant at C4/C5 of E,E-2,4-hexadienal is the first step for tropospheric degradation.

  5. Global atmospheric changes.

    OpenAIRE

    Piver, W T

    1991-01-01

    Increasing concentrations of CO2 and other greenhouse gases in the atmosphere can be directly related to global warming. In terms of human health, because a major cause of increasing atmospheric concentrations of CO2 is the increased combustion of fossil fuels, global warming also may result in increases in air pollutants, acid deposition, and exposure to ultraviolet (UV) radiation. To understand better the impacts of global warming phenomena on human health, this review emphasizes the proces...

  6. Comparative proteomic analysis reveals heart toxicity induced by chronic arsenic exposure in rats

    International Nuclear Information System (INIS)

    Huang, Qingyu; Xi, Guochen; Alamdar, Ambreen; Zhang, Jie; Shen, Heqing

    2017-01-01

    Arsenic is a widespread metalloid in the environment, which poses a broad spectrum of adverse effects on human health. However, a global view of arsenic-induced heart toxicity is still lacking, and the underlying molecular mechanisms remain unclear. By performing a comparative quantitative proteomic analysis, the present study aims to investigate the alterations of proteome profile in rat heart after long-term exposure to arsenic. As a result, we found that the abundance of 81 proteins were significantly altered by arsenic treatment (35 up-regulated and 46 down-regulated). Among these, 33 proteins were specifically associated with cardiovascular system development and function, including heart development, heart morphology, cardiac contraction and dilation, and other cardiovascular functions. It is further proposed that the aberrant regulation of 14 proteins induced by arsenic would disturb cardiac contraction and relaxation, impair heart morphogenesis and development, and induce thrombosis in rats, which is mediated by the Akt/p38 MAPK signaling pathway. Overall, these findings will augment our knowledge of the involved mechanisms and develop useful biomarkers for cardiotoxicity induced by environmental arsenic exposure. - Highlights: • Arsenic exposure has been associated with a number of adverse health effects. • The molecular mechanisms involved in arsenic-induced cardiotoxicity remain unclear. • Differential proteins were identified in arsenic-exposed rat heart by proteomics. • Arsenic induces heart toxicity through the Akt/p38 MAPK signaling pathway. - Label-free quantitative proteomic analysis of rat heart reveals putative mechanisms and biomarkers for arsenic-induced cardiotoxicity.

  7. Systematic review and meta-analysis of glyphosate exposure and risk of lymphohematopoietic cancers.

    Science.gov (United States)

    Chang, Ellen T; Delzell, Elizabeth

    2016-01-01

    This systematic review and meta-analysis rigorously examines the relationship between glyphosate exposure and risk of lymphohematopoietic cancer (LHC) including NHL, Hodgkin lymphoma (HL), multiple myeloma (MM), and leukemia. Meta-relative risks (meta-RRs) were positive and marginally statistically significant for the association between any versus no use of glyphosate and risk of NHL (meta-RR = 1.3, 95% confidence interval (CI) = 1.0-1.6, based on six studies) and MM (meta-RR = 1.4, 95% CI = 1.0-1.9; four studies). Associations were statistically null for HL (meta-RR = 1.1, 95% CI = 0.7-1.6; two studies), leukemia (meta-RR = 1.0, 95% CI = 0.6-1.5; three studies), and NHL subtypes except B-cell lymphoma (two studies each). Bias and confounding may account for observed associations. Meta-analysis is constrained by few studies and a crude exposure metric, while the overall body of literature is methodologically limited and findings are not strong or consistent. Thus, a causal relationship has not been established between glyphosate exposure and risk of any type of LHC.

  8. Analysis of correlation between pediatric asthma exacerbation and exposure to pollutant mixtures with association rule mining.

    Science.gov (United States)

    Toti, Giulia; Vilalta, Ricardo; Lindner, Peggy; Lefer, Barry; Macias, Charles; Price, Daniel

    2016-11-01

    Traditional studies on effects of outdoor pollution on asthma have been criticized for questionable statistical validity and inefficacy in exploring the effects of multiple air pollutants, alone and in combination. Association rule mining (ARM), a method easily interpretable and suitable for the analysis of the effects of multiple exposures, could be of use, but the traditional interest metrics of support and confidence need to be substituted with metrics that focus on risk variations caused by different exposures. We present an ARM-based methodology that produces rules associated with relevant odds ratios and limits the number of final rules even at very low support levels (0.5%), thanks to post-pruning criteria that limit rule redundancy and control for statistical significance. The methodology has been applied to a case-crossover study to explore the effects of multiple air pollutants on risk of asthma in pediatric subjects. We identified 27 rules with interesting odds ratio among more than 10,000 having the required support. The only rule including only one chemical is exposure to ozone on the previous day of the reported asthma attack (OR=1.14). 26 combinatory rules highlight the limitations of air quality policies based on single pollutant thresholds and suggest that exposure to mixtures of chemicals is more harmful, with odds ratio as high as 1.54 (associated with the combination day0 SO 2 , day0 NO, day0 NO 2 , day1 PM). The proposed method can be used to analyze risk variations caused by single and multiple exposures. The method is reliable and requires fewer assumptions on the data than parametric approaches. Rules including more than one pollutant highlight interactions that deserve further investigation, while helping to limit the search field. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. The analysis of QT interval and repolarization morphology of the heart in chronic exposure to lead.

    Science.gov (United States)

    Kiełtucki, J; Dobrakowski, M; Pawlas, N; Średniawa, B; Boroń, M; Kasperczyk, S

    2017-10-01

    There are no common recommendations regarding electrocardiographic monitoring in occupationally exposed workers. Therefore, the present study was designed to investigate whether exposure to lead results in an increase of selected electrocardiography (ECG) pathologies, such as QT interval prolongation and repolarization disorders, in occupationally exposed workers. The study group included 180 workers occupationally exposed to lead compounds. The exposed group was divided according to the median of the mean blood lead level (PbB mean ) calculated based on a series of measurements performed during 5-year observation period (35 µg/dl) into two subgroups: low exposure (LE, PbB mean = 20.0-35.0 µg/dl) and high exposure (HE, PbB mean = 35.1-46.4 µg/dl). The control group consisted of 69 healthy workers without occupational exposure to lead. ECG evaluation included the analysis of heart rate (HR), QT interval and repolarization abnormalities. Mean QT interval was significantly greater in the exposed population than in the control group by 2%. In the HE group, mean QT interval was significantly greater than in the control group by 4% and significantly different from those noted in the LE group. Positive correlations between QT interval and lead exposure indices were also reported. Besides, there was a negative correlation between HR and blood lead level. Increased concentration of lead in the blood above 35 μg/dl is associated with the QT interval prolongation, which may trigger arrhythmias when combined with other abnormalities, such as long QT syndrome. Therefore, electrocardiographic evaluation should be a part of a routine monitoring of occupationally exposed populations.

  10. Characterisation of volatile profile and sensory analysis of fresh-cut "Radicchio di Chioggia" stored in air or modified atmosphere.

    Science.gov (United States)

    Cozzolino, Rosaria; Martignetti, Antonella; Pellicano, Mario Paolo; Stocchero, Matteo; Cefola, Maria; Pace, Bernardo; De Giulio, Beatrice

    2016-02-01

    The volatile profile of two hybrids of "Radicchio di Chioggia", Corelli and Botticelli, stored in air or passive modified atmosphere (MAP) during 12 days of cold storage, was monitored by solid phase micro-extraction (SPME) GC-MS. Botticelli samples were also subjected to sensory analysis. Totally, 61 volatile organic compounds (VOCs) were identified in the headspace of radicchio samples. Principal component analysis (PCA) showed that fresh product possessed a metabolic content similar to that of the MAP samples after 5 and 8 days of storage. Projection to latent structures by partial least squares (PLS) regression analysis showed the volatiles content of the samples varied depending only on the packaging conditions. Specifically, 12 metabolites describing the time evolution and explaining the effects of the different storage conditions were highlighted. Finally, a PCA analysis revealed that VOCs profile significantly correlated with sensory attributes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Global atmospheric changes.

    Science.gov (United States)

    Piver, W T

    1991-12-01

    Increasing concentrations of CO2 and other greenhouse gases in the atmosphere can be directly related to global warming. In terms of human health, because a major cause of increasing atmospheric concentrations of CO2 is the increased combustion of fossil fuels, global warming also may result in increases in air pollutants, acid deposition, and exposure to ultraviolet (UV) radiation. To understand better the impacts of global warming phenomena on human health, this review emphasizes the processes that are responsible for the greenhouse effect, air pollution, acid deposition, and increased exposure to UV radiation.

  12. Analysis of Cigarette Smoke Deposition Within an In Vitro Exposure System for Simulating Exposure in the Human Respiratory Tract

    Directory of Open Access Journals (Sweden)

    Ishikawa Shinkichi

    2016-01-01

    Full Text Available For the risk assessment of airborne chemicals, a variety of in vitro direct exposure systems have been developed to replicate airborne chemical exposure in vivo. Since cells at the air-liquid interface are exposed to cigarette smoke as an aerosol in direct exposure systems, it is possible to reproduce the situation of cigarette smoke exposure in the human respiratory system using this device. However it is difficult to know whether the exposed cigarette smoke in this system is consistent with the smoke retained in the human respiratory tract. The purpose of this study is to clarify this point using the CULTEX® RFS module which is a recently developed direct exposure system. For this purpose, solanesol and acetaldehyde were respectively chosen as the particulate and gas/vapor phase representatives of smoke constituents, and their deposition and balance per unit area of cell culture surface of the RFS module were measured (dosimetry. We also conducted human retention studies to compare with the dosimetry data. By comparing inhaled smoke and exhaled smoke under three inhalation conditions, we estimated the regional retention and balance of each representative per unit surface area of the respiratory tract (mouth, bronchi, and alveoli separately. The deposition of solanesol and acetaldehyde per unit area of cell culture surface in the RFS module decreased dependent on the dilution flow rate and ranged from 0.26-0.0076%/cm2 in our experimental conditions. The ratio of deposited acetaldehyde to deposited solanesol ranged from 0.96-1.96 in the RFS module. The retention of solanesol and acetaldehyde per unit surface area in the mouth and the bronchi ranged from 0.095-0.0083%/cm2 in this study. The retention per unit surface area of alveoli was far lower than in the other two regions (0.0000063%/cm2. The ratio of retained acetaldehyde to retained solanesol ranged from 0.54-1.97. From these results, we concluded that the CULTEX® RFS module can simulate

  13. High Temperature Exposure of HPC – Experimental Analysis of Residual Properties and Thermal Response

    Directory of Open Access Journals (Sweden)

    Pavlík Zbyšek

    2016-01-01

    Full Text Available The effect of high temperature exposure on properties of a newly designed High Performance Concrete (HPC is studied in the paper. The HPC samples are exposed to the temperatures of 200, 400, 600, 800, and 1000°C respectively. Among the basic physical properties, bulk density, matrix density and total open porosity are measured. The mechanical resistivity against disruptive temperature action is characterised by compressive strength, flexural strength and dynamic modulus of elasticity. To study the chemical and physical processes in HPC during its high-temperature exposure, Simultaneous Thermal Analysis (STA is performed. Linear thermal expansion coefficient is determined as function of temperature using thermodilatometry (TDA. In order to describe the changes in microstructure of HPC induced by high temperature loading, MIP measurement of pore size distribution is done. Increase of the total open porosity and connected decrease of the mechanical parameters for temperatures higher than 200 °C were identified.

  14. FAULT TREE ANALYSIS FOR EXPOSURE TO REFRIGERANTS USED FOR AUTOMOTIVE AIR CONDITIONING IN THE U.S.

    Science.gov (United States)

    A fault tree analysis was used to estimate the number of refrigerant exposures of automotive service technicians and vehicle occupants in the United States. Exposures of service technicians can occur when service equipment or automotive air-conditioning systems leak during servic...

  15. Determination of the potential radiation exposure of the population close to the Asse II mine caused by deduction of radioactive substances with the discharge air in the normal operation using the ''Atmospheric Radionuclide-Transport-Model'' (ARTM)

    International Nuclear Information System (INIS)

    Esch, D.; Wittwer, C.

    2014-01-01

    Between 1967 and 1978 125.787 packages filled with low-level and intermediate-level radioactive waste were emplaced in the mining plant Asse II. Volatile radioactive substances like H-3, C-14 and Rn-222 are released from the emplaced waste. These substances reach the ventilated parts of the mine and are released with the discharge air. The potential radiation exposure of the population caused by deduction of radioactive substances with the discharge air in the normal operation is determined by the ''Atmospheric Radionuclide-Transport-Model'' (ARTM). As result the maximal deductions of volatile radioactive substances with the discharge air in the normal operation of the Asse II mine lead to radiation exposure of the population, which is considerably lower than the permissible values of application rate.

  16. A simple analysis of potential radiological exposure from geological disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    Amiro, B.D.; Dormuth, K.W.

    1996-02-01

    AECL has submitted an environmental impact statement (EIS) describing its proposal for geological disposal of Canada's nuclear fuel waste. The EIS presents a detailed analysis of potential radiation exposure of an individual of a critical group of people in a hypothetical case. In this report, we provide a simpler analysis of potential exposure in the hope that the inherent safety of the disposal will be more readily evident from the analysis. A key to the simplification is the elimination from the analysis of the complex transport processes through disposal vault sealing materials and the geosphere. We also eliminate the relatively complex function describing the failure of the thin-walled titanium containers in the case study presented in the EIS. We therefore conceptually replace the thin-walled titanium containers with thicker-walled copper containers, are expected to remain intact much longer than 10,000 a, the period for which a quantitative estimate of individual exposure is made. However, about 1 in 5000 containers could have small defects that were undetected during manufacture. Our analysis applies only to the case of an undisrupted vault. We assume that the vault and geosphere barriers remain intact and prevent immobile radionuclides from reaching the biosphere. However, we also assume that the three most important mobile radionuclides can escape through an undected manufacturing defect in the container wall, and that the flux of these radionuclides is diluted by well water being used by people. We have focused on 129 I, 36 Cl and 14 C, because these nuclides are found to be the dominant source of exposure in more complex analyses. If a single container released radionuclides to well water, we estimate dose rates of about 1 μSv.a -1 from drinking water and 29 μSv.a -1 , which the Atomic Eenrgy Control Board has adopted as a de minimis dose rate, i.e., a dose rate so small as to not warrant institutional control. We believe that the dose rates are

  17. Elemental analysis of lichen bioaccumulators before exposure as transplants in air pollution monitoring

    International Nuclear Information System (INIS)

    Pantelica, A.; Cercasov, V.

    2003-01-01

    Lichen transplants from relatively unpolluted sites are successfully used as heavy metal bioaccumulators for long-term air pollution monitoring. Significant element accumulations are generally revealed after 6 to 12 months of exposure. The main objective of this interdisciplinary research is to get a low-price survey of the air pollution level in some critical areas of Romania by nuclear and atomic analytical methods, based on the element accumulating property of transplanted lichens. The lichen species Evernia prunastri and Pseudevernia furfuracea collected from the Prealps, northeast Italy, have been selected for this study. Experimental setup for standardized lichen exposure needs special plastic frames ('little traps': 15 · 15 · 1.5 cm, with 1cm 2 mesh) which are fixed horizontally on stainless steel posts at about 1.5 m above the ground. Prior to exposure, the lichen material is cleansed of some vegetal impurities and then shortly washed using de-ionised water. The initial (zero-level) contents of lichens were determined by Instrumental Neutron Activation Analysis (INAA) and Energy Dispersive X-Ray Fluorescence Analysis (EDXRFA) methods. INAA was carried out at the Institute of Physics and Nuclear Engineering in Bucharest (IFIN) and while EDXRFA at the University of Hohenheim in Stuttgart. The investigated elements were: As, Br, Ca, Cd, Co, Cr, Cu, Fe, K, Mn, Ni, Pb, S, Sb, Se, V and Zn. From among them, Cd, Co and Sb can be determined only by INAA and ICP-MS, Pb only by EDXRFA and PIXE, and S only by EDXRFA. A statistical intercomparison of the results allowed a good quality control of the used analytical methods for these specific matrices. This work was supported in part by European Commission Center of Excellence Project ICA1-CT-2000-70023: IDRANAP (Inter-Disciplinary Research and Applications based on Nuclear and Atomic Physics), Work Package 2 (Air pollution monitoring by sampling airborne particulate matter combined with lichen bioaccumulator exposure

  18. Personal exposure to mixtures of volatile organic compounds: modeling and further analysis of the RIOPA data.

    Science.gov (United States)

    Batterman, Stuart; Su, Feng-Chiao; Li, Shi; Mukherjee, Bhramar; Jia, Chunrong

    2014-06-01

    affect VOC exposures, many personal, environmental, and socioeconomic determinants remain to be identified, and the significance and applicability of the determinants reported in the literature are uncertain. To help answer these unresolved questions and overcome limitations of previous analyses, this project used several novel and powerful statistical modeling and analysis techniques and two large data sets. The overall objectives of this project were (1) to identify and characterize exposure distributions (including extreme values), (2) evaluate mixtures (including dependencies), and (3) identify determinants of VOC exposure. METHODS VOC data were drawn from two large data sets: the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study (1999-2001) and the National Health and Nutrition Examination Survey (NHANES; 1999-2000). The RIOPA study used a convenience sample to collect outdoor, indoor, and personal exposure measurements in three cities (Elizabeth, NJ; Houston, TX; Los Angeles, CA). In each city, approximately 100 households with adults and children who did not smoke were sampled twice for 18 VOCs. In addition, information about 500 variables associated with exposure was collected. The NHANES used a nationally representative sample and included personal VOC measurements for 851 participants. NHANES sampled 10 VOCs in common with RIOPA. Both studies used similar sampling methods and study periods. Specific Aim 1. To estimate and model extreme value exposures, extreme value distribution models were fitted to the top 10% and 5% of VOC exposures. Health risks were estimated for individual VOCs and for three VOC mixtures. Simulated extreme value data sets, generated for each VOC and for fitted extreme value and lognormal distributions, were compared with measured concentrations (RIOPA observations) to evaluate each model's goodness of fit. Mixture distributions were fitted with the conventional finite mixture of normal distributions and the semi

  19. Thermogravimetric Analysis of Textile Dyeing Sludge (TDS) in N₂/CO₂/O₂ Atmospheres and its Combustion Model with Coal.

    Science.gov (United States)

    Zhuo, Zhongxu; Liu, Jingyong; Sun, Shuiyu; Kuo, Jiahong; Sun, Jian; Chang, Ken-Lin; Fu, Jiewen

    2018-01-01

      The combustion characteristics of textile dyeing sludge (TDS) in N2/O2, CO2/O2, and N2/CO2 atmospheres, and blends of TDS with coal were analyzed using TGA (thermogravimetric analysis). Results showed that the replacement of N2 by CO2 resulted in negative effects on the combustion and pyrolysis of TDS. Comparing N2/O2 and CO2/O2 atmospheres, combustion of TDS was easier in a N2/O2 atmosphere, but the residual mass after TDS pyrolysis in pure CO2 was less than that in N2 by approximately 4.51%. When the proportion of TDS was 30-50% in the blends of coal with TDS, a synergistic interaction clearly occurred, and it significantly promoted combustion. In considering different combustion parameters, the optimal proportion of TDS may be between 20-30%. The activation energy Ea value decreased from 155.6 kJ/mol to 53.35 kJ/mol with an increasing TDS proportion from 0% to 50%, and it rapidly decreased when the TDS proportion was below 20%.

  20. Human health risk assessment of lead pollution in atmospheric deposition in Baoshan District, Shanghai.

    Science.gov (United States)

    Chen, Yuanyuan; Wang, Jun; Shi, Guitao; Sun, Xiaojing; Chen, Zhenlou; Xu, Shiyuan

    2011-12-01

    The lead (Pb) content in atmospheric deposition was determined at 42 sampling sites in Baoshan District of Shanghai, China. Based on exposure and dose-response assessments, the health risk caused by Pb exposure in atmospheric deposition was investigated. The results indicated that Pb was significantly accumulated in atmospheric deposition. The spatial distribution of Pb was mapped by geostatistical analysis, and the results showed that pollution hotspots were present at traffic and industrial zones. Ingestion was the main route of Pb exposure in both adults and children. For children the risk value was above 1, whereas it was below 1 for the adult group. Therefore, children belong to the high-risk group for Pb exposure from atmospheric deposition in the observed area of Shanghai, China.

  1. Short-term exposure to atmospheric ammonia does not affect frost hardening of needles from three- and five-year-old Scots pine trees

    NARCIS (Netherlands)

    Clement, J.M A M; van Hasselt, P.R; van Eerden, L.J.M.; Dueck, T.A.

    The effect of atmospheric ammonia on frost hardening of needles from 3- and 5-year-old Scots pine trees was investigated. Trees were exposed to various concentrations of NH(3) during different hardening stages under laboratory conditions and in experiments with open-top chambers under a natural

  2. Soil respiration, root biomass, and root turnover following long-term exposure of northern forests to elevated atmospheric CO2 and tropospheric O3

    Science.gov (United States)

    Kurt S. Pregitzer; Andrew J. Burton; John S. King; Donald R. Zak

    2008-01-01

    The Rhinelander free-air CO2 enrichment (FACE) experiment is designed to understand ecosystem response to elevated atmospheric carbon dioxide (+CO2) and elevated tropospheric ozone (+O3). The objectives of this study were: to understand how soil respiration responded to the experimental treatments; to...

  3. Symbolic Analysis of Heart Rate Variability During Exposure to Musical Auditory Stimulation.

    Science.gov (United States)

    Vanderlei, Franciele Marques; de Abreu, Luiz Carlos; Garner, David Matthew; Valenti, Vitor Engrácia

    2016-01-01

    In recent years, the application of nonlinear methods for analysis of heart rate variability (HRV) has increased. However, studies on the influence of music on cardiac autonomic modulation in those circumstances are rare. The research team aimed to evaluate the acute effects on HRV of selected auditory stimulation by 2 musical styles, measuring the results using nonlinear methods of analysis: Shannon entropy, symbolic analysis, and correlation-dimension analysis. Prospective control study in which the volunteers were exposed to music and variables were compared between control (no auditory stimulation) and during exposure to music. All procedures were performed in a sound-proofed room at the Faculty of Science and Technology at São Paulo State University (UNESP), São Paulo, Brazil. Participants were 22 healthy female students, aged between 18 and 30 y. Prior to the actual intervention, the participants remained at rest for 20 min, and then they were exposed to one of the selected types of music, either classical baroque (64-84 dB) or heavy-metal (75-84 dB). Each musical session lasted a total of 5 min and 15 s. At a point occurring up to 1 wk after that day, the participants listened to the second type of music. The 2 types of music were delivered in a random sequence that depended on the group to which the participant was assigned. The study analyzed the following HRV indices through Shannon entropy; symbolic analysis-0V%, 1V%, 2LV%, and 2ULV%; and correlation-dimension analysis. During exposure to auditory stimulation by heavy-metal or classical baroque music, the study established no statistically significant variations regarding the indices for the Shannon entropy; the symbolic analysis-0V%, 1V%, and 2ULV%; and the correlation-dimension analysis. However, during heavy-metal music, the 2LV% index in the symbolic analysis was reduced compared with the controls. Auditory stimulation with the heavy-metal music reduced the parasympathetic modulation of HRV

  4. Atmospheric contamination

    International Nuclear Information System (INIS)

    Gruetter, Juerg

    1997-01-01

    It is about the levels of contamination in center America, the population's perception on the problem, effects of the atmospheric contamination, effects in the environment, causes of the atmospheric contamination, possibilities to reduce the atmospheric contamination and list of Roeco Swisscontac in atmospheric contamination

  5. Atmospheric retrieval analysis of the directly imaged exoplanet HR 8799b

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae-Min [University of Zürich, Institute for Theoretical Physics, Winterthurerstrasse 190, CH-8057 Zürich (Switzerland); Heng, Kevin [University of Bern, Center for Space and Habitability, Sidlerstrasse 5, CH-3012 Bern (Switzerland); Irwin, Patrick G. J., E-mail: lee@physik.uzh.ch, E-mail: kevin.heng@csh.unibe.ch, E-mail: irwin@atm.ox.ac.uk [University of Oxford, Atmospheric, Oceanic and Planetary Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU (United Kingdom)

    2013-12-01

    Directly imaged exoplanets are unexplored laboratories for the application of the spectral and temperature retrieval method, where the chemistry and composition of their atmospheres are inferred from inverse modeling of the available data. As a pilot study, we focus on the extrasolar gas giant HR 8799b, for which more than 50 data points are available. We upgrade our non-linear optimal estimation retrieval method to include a phenomenological model of clouds that requires the cloud optical depth and monodisperse particle size to be specified. Previous studies have focused on forward models with assumed values of the exoplanetary properties; there is no consensus on the best-fit values of the radius, mass, surface gravity, and effective temperature of HR 8799b. We show that cloud-free models produce reasonable fits to the data if the atmosphere is of super-solar metallicity and non-solar elemental abundances. Intermediate cloudy models with moderate values of the cloud optical depth and micron-sized particles provide an equally reasonable fit to the data and require a lower mean molecular weight. We report our best-fit values for the radius, mass, surface gravity, and effective temperature of HR 8799b. The mean molecular weight is about 3.8, while the carbon-to-oxygen ratio is about unity due to the prevalence of carbon monoxide. Our study emphasizes the need for robust claims about the nature of an exoplanetary atmosphere to be based on analyses involving both photometry and spectroscopy and inferred from beyond a few photometric data points, such as are typically reported for hot Jupiters.

  6. Assessment of human exposure to pesticides by hair analysis: The case of vegetable-producing areas in Burkina Faso.

    Science.gov (United States)

    Lehmann, Edouard; Oltramare, Christelle; Nfon Dibié, Jean-Jacques; Konaté, Yacouba; de Alencastro, Luiz Felippe

    2018-02-01

    The present work assesses human exposure to pesticides in vegetable-producing areas in Burkina Faso, using hair as an indicator. The study design includes a comparison between operators who are occupationally exposed while working in the fields and a reference population (i.e. not occupationally exposed) to evaluate both occupational and indirect exposures. Hair samples from volunteers (n=101) were positive for 17 pesticides (38 analyzed). Acetamiprid, desethylatrazine, carbofuran, and deltamethrin were detected for the first time in field samples. With a maximum of 9 residues per sample, pesticide exposure was ubiquitous in both populations. Contamination by acetamiprid, cypermethrin, and lambda-cyhalothrin (used in vegetable production) prevailed in operator samples. For other pesticides, such as imidacloprid and deltamethrin, no significant difference was found. This indicates a potentially large environmental exposure (dietary intake or atmospheric contamination) or the prevalence of other contamination sources. The present findings are concerning, as detected levels are globally higher than those previously reported, and indicate exposure to endocrine disrupting chemicals and probable carcinogens. Hair was found to be a suitable matrix for biomonitoring human exposure to pesticides and assessing dominant factors (i.e. sex, age, and protective equipment) in subgroups, as well as identifying geographical contamination patterns. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Analysis of wave-like oscillations in parameters of sporadic E layer and neutral atmosphere

    Czech Academy of Sciences Publication Activity Database

    Mošna, Zbyšek; Koucká Knížová, Petra

    90-91, SI (2012), s. 172-178 ISSN 1364-6826. [IAGA/ICMA/CAWSES-II TG4 Workshop on Vertical Coupling in the Atmosphere-Ionosphere System /4./. Prague, 14.02.2011-18.02.2011] R&D Projects: GA AV ČR IAA300420704 Institutional support: RVO:68378289 Keywords : Sporadic E * Planetary waves * Tidal waves * Mid-latitude ionosphere Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.417, year: 2012 http://www.sciencedirect.com/science/article/pii/S1364682612001186

  8. Expectations for Particulate Contamination Relevant to in Situ Atmospheric Sampling for Compositional Analysis at Uranus

    Science.gov (United States)

    Wong, M. H.

    2017-12-01

    NASA and ESA are considering options for in situ science with atmospheric entry probes to the ice giants Uranus and Neptune. Nominal probe entry mass is in the 300-kg range, although a miniaturized secondary probe option is being studied in the 30-kg range. In all cases, compositional sampling would commence near the 100-mbar level at Uranus, after ejection of the heat shield and deployment of the descent parachute. In this presentation, I review existing literature on the composition, mass loading, and vertical distribution of condensed material that the probe may encounter. Sample inlets for measurement of the gas composition should be heated to avoid potential buildup of condensate, which would block the flow of atmospheric gas into composition sensors. Heating rate and temperature values -- sufficient to keep sample inlets clean under various assumptions -- will be presented. Three main types of condensed material will be considered: Stratospheric hydrocarbon ices: Solar UV photolyzes CH4, leading to the production of volatile hydrocarbons with higher C/H ratios. These species diffuse from their production regions into colder levels where the ices of C2H2, C2H6, and C4H2 condense. Some studies have also considered condensation of C3H8, C4H10, C6H6, and C6H2. Gunk: The hydrocarbon ices are thought to become polymerized due to irradiation from solar UV. The exact composition of the resulting gunk is not known. Solid-state photochemical processing may produce the traces of reddish (blue-absorbing) haze material, present in the troposphere at temperatures warm enough to sublimate the simple hydrocarbon ices. Tropospheric ices: In the region accessible to probes under study (P < 10 bar), much thicker condensation clouds may form from volatile gases CH4, NH3, and H2S. If large amounts of NH3 are sequestered in the deeper H2O liquid cloud, then the S/N ratio could exceed 1 in the probe-accessible region of the atmosphere, leading to NH4SH and H2S ices below the CH4

  9. Evaluation and application of multi-decadal visibility data for trend analysis of atmospheric haze

    Directory of Open Access Journals (Sweden)

    C. Li

    2016-03-01

    Full Text Available There are few multi-decadal observations of atmospheric aerosols worldwide. This study applies global hourly visibility (Vis observations at more than 3000 stations to investigate historical trends in atmospheric haze over 1945–1996 for the US, and over 1973–2013 for Europe and eastern Asia. A comprehensive data screening and processing framework is developed and applied to minimize uncertainties and construct monthly statistics of inverse visibility (1/Vis. This data processing includes removal of relatively clean cases with high uncertainty, and change point detection to identify and separate methodological discontinuities such as the introduction of instrumentation. Although the relation between 1/Vis and atmospheric extinction coefficient (bext varies across different stations, spatially coherent trends of the screened 1/Vis data exhibit consistency with the temporal evolution of collocated aerosol measurements, including the bext trend of −2.4 % yr−1 (95 % CI: −3.7, −1.1 % yr−1 vs. 1/Vis trend of −1.6 % yr−1 (95 % CI: −2.4, −0.8 % yr−1 over the US for 1989–1996, and the fine aerosol mass (PM2.5 trend of −5.8 % yr−1 (95 % CI: −7.8, −4.2 % yr−1 vs. 1/Vis trend of −3.4 % yr−1 (95 % CI: −4.4, −2.4 % yr−1 over Europe for 2006–2013. Regional 1/Vis and Emissions Database for Global Atmospheric Research (EDGAR sulfur dioxide (SO2 emissions are significantly correlated over the eastern US for 1970–1995 (r = 0.73, over Europe for 1973–2008 (r ∼ 0.9 and over China for 1973–2008 (r ∼ 0.9. Consistent "reversal points" from increasing to decreasing in SO2 emission data are also captured by the regional 1/Vis time series (e.g., late 1970s for the eastern US, early 1980s for western Europe, late 1980s for eastern Europe, and mid 2000s for China. The consistency of 1/Vis trends with other in situ measurements and emission data demonstrates promise in applying these quality assured 1/Vis data

  10. Theory of stellar atmospheres an introduction to astrophysical non-equilibrium quantitative spectroscopic analysis

    CERN Document Server

    Hubeny, Ivan

    2015-01-01

    This book provides an in-depth and self-contained treatment of the latest advances achieved in quantitative spectroscopic analyses of the observable outer layers of stars and similar objects. Written by two leading researchers in the field, it presents a comprehensive account of both the physical foundations and numerical methods of such analyses. The book is ideal for astronomers who want to acquire deeper insight into the physical foundations of the theory of stellar atmospheres, or who want to learn about modern computational techniques for treating radiative transfer in non-equilibrium situations. It can also serve as a rigorous yet accessible introduction to the discipline for graduate students.

  11. Phylogenetic analysis of atmospheric halotolerant bacterial communities at high altitude in an Asian dust (KOSA) arrival region, Suzu City

    Energy Technology Data Exchange (ETDEWEB)

    Maki, Teruya, E-mail: makiteru@t.kanazawa-u.ac.jp [College of Science and Engineering, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192 (Japan); Susuki, Shinzi; Kobayashi, Fumihisa [College of Science and Engineering, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192 (Japan); Kakikawa, Makiko [Institute of Nature and Environmental Technology, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192 (Japan); Tobo, Yutaka [Frontier Science Organization, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192 (Japan); Yamada, Maromu [Faculty of Environmental and Symbiotic Science, Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto 862-8502 (Japan); Higashi, Tomomi [Hygiene, Kanazawa University School of Medicine, 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640 (Japan); Matsuki, Atsushi; Hong, Chunsang [Frontier Science Organization, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192 (Japan); Hasegawa, Hiroshi [College of Science and Engineering, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192 (Japan); Iwasaka, Yasunobu [Frontier Science Organization, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192 (Japan)

    2010-09-15

    The microbial communities transported by Asian desert dust (KOSA) events have attracted much attention as bioaerosols because the transported microorganisms are thought to influence the downwind ecosystems in Korea and Japan. However, the atmospheric microbial community has not been investigated at high altitude in the KOSA arrival area. In this study, to estimate the viability and diversity of atmospheric halotolerant bacteria, which are expected to resist to various environmental stresses as well as high salinities, bioaerosol samples were collected at 10 and 600 m above the ground within the KOSA arrival area, Suzu City, Japan, during KOSA events. During the sampling period, the particle numbers at 600 m were higher than those at 10 m, suggesting that large particles of aerosol fall from the high altitude of 600 m to the ground surface. The microorganisms in bioaerosol samples grew in media containing up to 15% NaCl concentrations demonstrating the viability of the halotolerant bacteria in bioaerosol samples. The PCR-DGGE analysis using 16S rDNA revealed that the bacterial species in NaCl-amended cultures were similar to the bacteria detected from the genomic DNA directly extracted from the bioaerosol samples. The 16S rDNA sequences of bacterial communities in bioaerosol samples were classified into 4 phylotypes belonging to the Bacilluscereus or Bacillussubtilis group. The bioaerosol samples collected at 600 m included 2 phylotypes belonging to B. subtilis, and one phylotype among all 4 phylotypes was identical between the samples at 10 and 600 m. In the atmosphere at 600 m, the halotolerant bacterial community was expected to remain viable, and the species composition was expected to include a few species of the genus Bacillus. During this investigation period, these atmospheric bacteria may have been vertically transported to the ground surface, where the long-range KOSA particle transport from China is frequently observed.

  12. Phylogenetic analysis of atmospheric halotolerant bacterial communities at high altitude in an Asian dust (KOSA) arrival region, Suzu City

    International Nuclear Information System (INIS)

    Maki, Teruya; Susuki, Shinzi; Kobayashi, Fumihisa; Kakikawa, Makiko; Tobo, Yutaka; Yamada, Maromu; Higashi, Tomomi; Matsuki, Atsushi; Hong, Chunsang; Hasegawa, Hiroshi; Iwasaka, Yasunobu

    2010-01-01

    The microbial communities transported by Asian desert dust (KOSA) events have attracted much attention as bioaerosols because the transported microorganisms are thought to influence the downwind ecosystems in Korea and Japan. However, the atmospheric microbial community has not been investigated at high altitude in the KOSA arrival area. In this study, to estimate the viability and diversity of atmospheric halotolerant bacteria, which are expected to resist to various environmental stresses as well as high salinities, bioaerosol samples were collected at 10 and 600 m above the ground within the KOSA arrival area, Suzu City, Japan, during KOSA events. During the sampling period, the particle numbers at 600 m were higher than those at 10 m, suggesting that large particles of aerosol fall from the high altitude of 600 m to the ground surface. The microorganisms in bioaerosol samples grew in media containing up to 15% NaCl concentrations demonstrating the viability of the halotolerant bacteria in bioaerosol samples. The PCR-DGGE analysis using 16S rDNA revealed that the bacterial species in NaCl-amended cultures were similar to the bacteria detected from the genomic DNA directly extracted from the bioaerosol samples. The 16S rDNA sequences of bacterial communities in bioaerosol samples were classified into 4 phylotypes belonging to the Bacilluscereus or Bacillussubtilis group. The bioaerosol samples collected at 600 m included 2 phylotypes belonging to B. subtilis, and one phylotype among all 4 phylotypes was identical between the samples at 10 and 600 m. In the atmosphere at 600 m, the halotolerant bacterial community was expected to remain viable, and the species composition was expected to include a few species of the genus Bacillus. During this investigation period, these atmospheric bacteria may have been vertically transported to the ground surface, where the long-range KOSA particle transport from China is frequently observed.

  13. Neutron activation analysis on sediments from Victoria Land, Antarctica. Multi-elemental characterization of potential atmospheric dust sources

    International Nuclear Information System (INIS)

    Baccolo, G.; Maggi, V.; Baroni, C.; Clemenza, M.; Motta, A.; Nastasi, M.; Previtali, E.; University of Milano-Bicocca, Milan; Delmonte, B.; Salvatore, M.C.

    2014-01-01

    The elemental composition of 40 samples of mineral sediments collected in Victoria Land, Antarctica, in correspondence of ice-free sites, is presented. Concentration of 36 elements was determined by instrumental neutron activation analysis, INAA. The selection of 6 standard reference materials and the development of a specific analytical procedure allowed to reduce measurements uncertainties and to verify the reproducibility of the results. The decision to analyze sediment samples from Victoria Land ice-free areas is related to recent investigations regarding mineral dust content in the TALos Dome ICE core (159deg11'E; 72deg49'S, East Antarctica, Victoria Land), in which a coarse local fraction of dust was recognized. The characterization of Antarctic potential source areas of atmospheric mineral dust is the first step to identify the active sources of dust for the Talos Dome area and to reconstruct the atmospheric pathways followed by air masses in this region during different climatic periods. Principal components analysis was used to identify elements and samples correlations; attention was paid specially to rare earth elements (REE) and incompatible/compatible elements (ICE) in respect to iron, which proved to be the most discriminating elemental groups. The analysis of REE and ICE concentration profiles supported evidences of chemical weathering in ice-free areas of Victoria Land, whereas cold and dry climate conditions of the Talos Dome area and in general of East Antarctica. (author)

  14. Monitoring the heavy metal atmospheric deposition in Romania using the neutron activation analysis of bio-indicators

    International Nuclear Information System (INIS)

    Lucaciu, Adriana

    1997-01-01

    This research is the direct result of a protocol between NIPNE-HH Bucharest, Romania and JINR-Dubna, Russia on one side, and NIPNE-HH Bucharest, Romania and the University of Trondheim, Norway on the other side. Since the summer of 1995, a systematic sampling of bio-indicators has been carried out. The bio-indicators are represented by three species of bryophytes with an endemic development in the Romanian area: Hylocomium splendens, Hypnum cupresiforme and Pleurozium schreberi. A large area of 45,000 km 2 , including the Carpathian Arch between the Olt River Gorge (Southern Carpathian Mountains) and the northern Romanian border (Eastern Carpathian Mountains) was covered. Some of the samples were prepared in the laboratory and analyzed by nuclear analysis methods of a high sensitivity and accuracy i.e., neutron activation analysis and atomic absorption spectrometry. Other samples are to be prepared and analyzed. The results will be shown as distribution maps for heavy metal concentrations in the studied area. The analysis were carried out at NIPNE-HH-Bucharest, JINR-Dubna and Trondheim University. Part of the results have already been included in the European Atlas of the Heavy Metal Atmospheric Depositions, published by the Northern Countries Council. The distribution maps of atmospheric depositions in Romania will also be included in the above mentioned Atlas. (author)

  15. High-resolution surface analysis for extended-range downscaling with limited-area atmospheric models

    Science.gov (United States)

    Separovic, Leo; Husain, Syed Zahid; Yu, Wei; Fernig, David

    2014-12-01

    High-resolution limited-area model (LAM) simulations are frequently employed to downscale coarse-resolution objective analyses over a specified area of the globe using high-resolution computational grids. When LAMs are integrated over extended time frames, from months to years, they are prone to deviations in land surface variables that can be harmful to the quality of the simulated near-surface fields. Nudging of the prognostic surface fields toward a reference-gridded data set is therefore devised in order to prevent the atmospheric model from diverging from the expected values. This paper presents a method to generate high-resolution analyses of land-surface variables, such as surface canopy temperature, soil moisture, and snow conditions, to be used for the relaxation of lower boundary conditions in extended-range LAM simulations. The proposed method is based on performing offline simulations with an external surface model, forced with the near-surface meteorological fields derived from short-range forecast, operational analyses, and observed temperatures and humidity. Results show that the outputs of the surface model obtained in the present study have potential to improve the near-surface atmospheric fields in extended-range LAM integrations.

  16. Atmospheric pollution in an urban environment by tree bark biomonitoring--part I: trace element analysis.

    Science.gov (United States)

    Guéguen, Florence; Stille, Peter; Lahd Geagea, Majdi; Boutin, René

    2012-03-01

    Tree bark has been shown to be a useful biomonitor of past air quality because it accumulates atmospheric particulate matter (PM) in its outermost structure. Trace element concentrations of tree bark of more than 73 trees allow to elucidate the impact of past atmospheric pollution on the urban environment of the cities of Strasbourg and Kehl in the Rhine Valley. Compared to the upper continental crust (UCC) tree barks are strongly enriched in Mn, Ni, Cu, Zn, Cd and Pb. To assess the degree of pollution of the different sites in the cities, a geoaccumulation index I(geo) was applied. Global pollution by V, Ni, Cr, Sb, Sn and Pb was observed in barks sampled close to traffic axes. Cr, Mo, Cd pollution principally occurred in the industrial area. A total geoaccumulation index I(GEO-tot) was defined; it is based on the total of the investigated elements and allows to evaluate the global pollution of the studied environment by assembling the I(geo) indices on a pollution map. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Performance analysis of an adaptive optics system for free-space optics communication through atmospheric turbulence.

    Science.gov (United States)

    Wang, Yukun; Xu, Huanyu; Li, Dayu; Wang, Rui; Jin, Chengbin; Yin, Xianghui; Gao, Shijie; Mu, Quanquan; Xuan, Li; Cao, Zhaoliang

    2018-01-18

    The performance of free-space optics communication (FSOC) is greatly degraded by atmospheric turbulence. Adaptive optics (AO) is an effective method for attenuating the influence. In this paper, the influence of the spatial and temporal characteristics of turbulence on the performance of AO in a FSOC system is investigated. Based on the Greenwood frequency (GF) and the ratio of receiver aperture diameter to atmospheric coherent length (D/r 0 ), the relationship between FSOC performance (CE) and AO parameters (corrected Zernike modes number and bandwidth) is derived for the first time. Then, simulations and experiments are conducted to analyze the influence of AO parameters on FSOC performance under different GF and D/r 0 . The simulation and experimental results show that, for common turbulence conditions, the number of corrected Zernike modes can be fixed at 35 and the bandwidth of the AO system should be larger than the GF. Measurements of the bit error rate (BER) for moderate turbulence conditions (D/r 0  = 10, f G  = 60 Hz) show that when the bandwidth is two times that of GF, the average BER is decreased by two orders of magnitude compared with f G /f 3dB  = 1. These results and conclusions can provide important guidance in the design of an AO system for FSOC.

  18. Fourier analysis of Solar atmospheric numerical simulations accelerated with GPUs (CUDA).

    Science.gov (United States)

    Marur, A.

    2015-12-01

    Solar dynamics from the convection zone creates a variety of waves that may propagate through the solar atmosphere. These waves are important in facilitating the energy transfer between the sun's surface and the corona as well as propagating energy throughout the solar system. How and where these waves are dissipated remains an open question. Advanced 3D numerical simulations have furthered our understanding of the processes involved. Fourier transforms to understand the nature of the waves by finding the frequency and wavelength of these waves through the simulated atmosphere, as well as the nature of their propagation and where they get dissipated. In order to analyze the different waves produced by the aforementioned simulations and models, Fast Fourier Transform algorithms will be applied. Since the processing of the multitude of different layers of the simulations (of the order of several 100^3 grid points) would be time intensive and inefficient on a CPU, CUDA, a computing architecture that harnesses the power of the GPU, will be used to accelerate the calculations.

  19. A re-analysis of the atmospheric and ionospheric effects of the Flixborough explosion

    Science.gov (United States)

    Krasnov, V. M.; Drobzheva, Ya. V.; Venart, J. E. S.; Lastovicka, J.

    2003-07-01

    The ionospheric record of the 1974 cyclohexane vapour cloud explosion (VCE) accident near Flixborough is re-examined in light of a new theory used to describe the acoustic field in the atmosphere and ionosphere caused by explosions on the ground. The reconstructed oblique Doppler sounding records from six radio traces agree remarkably well with experimental results when a ground source explosion yield of 283+/-38tons of TNT is utilized. This result, when compared to the detonation of large hydrocarbon fuel-drop-air clouds, suggests that only 14+/-2tons of cyclohexane was involved in the explosion. Additionally the time of the explosion determined from the model, 15:52:08+/-6, agrees, within the mutual uncertainty, with that determined seismically, 15:52:15.5+/-2 UT. The precision in the value of the yield and accuracy of the time of the explosion validates the model used to describe the propagation of acoustic waves by taking into account expansion, absorption, and non-linear and inhomogeneous effects in the atmosphere and ionosphere.

  20. Analysis of the Effects of ENSO and Atmospheric Rivers on Precipitation in Los Angeles County

    Science.gov (United States)

    Santacruz, A.; Lamb, K.

    2017-12-01

    The Winter 2016-2017 season in California was marked by substantial amounts of precipitation; this resulted in critically-low reservoirs filling up and the removal of most of California from drought status. The year prior was characterized by one of the strongest El Nino-Southern Oscillation (ENSO) events, though it did not produce nearly enough precipitation as the 2016-2017 season. The major contributors to the increased rainfall during the 2016-2017 season were climactic phenomenon known as atmospheric rivers (ARs), which transport water vapor through the atmosphere in narrow bands, and are known to produce extreme rain events. Determining the exact timing, landfall areas, and total precipitation amounts of ARs is currently of great interest; a recent study showed that extreme weather events are likely to increase in California in the coming years, which motivates research into how phenomenon such as ENSO and ARs play a role. Using long-term daily rain gauge data provided by the Los Angeles County Department of Public Works, we compute the precipitation volume and storm count for various locations in Los Angeles County and identify anomalies. These data will then be compared with the occurrence and intensity of AR and ENSO events by using NOAA's NOI and ESRL AR data. The results can be used to provide a better grasp of extreme climactic patterns and their effects on the amount of precipitation in the region.

  1. Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Dirks, Wendy; Roberts, Nick M.W.; Patel, Jaiminkumar G.; Hodgson, Susan; Pless-Mulloli, Tanja; Walton, Pamela; Parrish, Randall R.

    2016-01-01

    We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5–8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2–3 years for molars, first 1–2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2 µg Pb/g) with 208 Pb/ 206 Pb (mean ±2σ: 2.126–2.079) 208 Pb/ 206 Pb (mean ±2σ: 0.879–0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM 10 , PM 2.5 ) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4 µgPb/g) with 208 Pb/ 206 Pb (mean ±2σ: 2.145–2.117) 208 Pb/ 206 Pb (mean ±2σ: 0.898–0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1–2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood changes in the isotope composition of blood Pb. Our pilot

  2. Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J. [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne (United Kingdom); British Geological Survey, Keyworth, Nottingham (United Kingdom); Dirks, Wendy [Department of Anthropology, Durham University, Durham (United Kingdom); Roberts, Nick M.W. [NERC Isotope Geosciences Laboratory, British Geological Survey, Nottingham (United Kingdom); Patel, Jaiminkumar G. [Leeds Dental Institute, University Leeds, Leeds (United Kingdom); Hodgson, Susan [MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, Imperial College London (United Kingdom); Pless-Mulloli, Tanja [Institute of Health and Society, Newcastle University, Newcastle upon Tyne (United Kingdom); Walton, Pamela [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne (United Kingdom); Parrish, Randall R. [British Geological Survey, Keyworth, Nottingham (United Kingdom)

    2016-04-15

    We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and {sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5–8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2–3 years for molars, first 1–2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2 µg Pb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.126–2.079) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.879–0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM{sub 10}, PM{sub 2.5}) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4 µgPb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.145–2.117) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.898–0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1–2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood

  3. A model to systematically employ professional judgment in the Bayesian Decision Analysis for a semiconductor industry exposure assessment.

    Science.gov (United States)

    Torres, Craig; Jones, Rachael; Boelter, Fred; Poole, James; Dell, Linda; Harper, Paul

    2014-01-01

    Bayesian Decision Analysis (BDA) uses Bayesian statistics to integrate multiple types of exposure information and classify exposures within the exposure rating categorization scheme promoted in American Industrial Hygiene Association (AIHA) publications. Prior distributions for BDA may be developed from existing monitoring data, mathematical models, or professional judgment. Professional judgments may misclassify exposures. We suggest that a structured qualitative risk assessment (QLRA) method can provide consistency and transparency in professional judgments. In this analysis, we use a structured QLRA method to define prior distributions (priors) for BDA. We applied this approach at three semiconductor facilities in South Korea, and present an evaluation of the performance of structured QLRA for determination of priors, and an evaluation of occupational exposures using BDA. Specifically, the structured QLRA was applied to chemical agents in similar exposure groups to identify provisional risk ratings. Standard priors were developed for each risk rating before review of historical monitoring data. Newly collected monitoring data were used to update priors informed by QLRA or historical monitoring data, and determine the posterior distribution. Exposure ratings were defined by the rating category with the highest probability--i.e., the most likely. We found the most likely exposure rating in the QLRA-informed priors to be consistent with historical and newly collected monitoring data, and the posterior exposure ratings developed with QLRA-informed priors to be equal to or greater than those developed with data-informed priors in 94% of comparisons. Overall, exposures at these facilities are consistent with well-controlled work environments. That is, the 95th percentile of exposure distributions are ≤50% of the occupational exposure limit (OEL) for all chemical-SEG combinations evaluated; and are ≤10% of the limit for 94% of chemical-SEG combinations evaluated.

  4. A longitudinal analysis of prenatal exposure to methylmercury and fatty acids in the Seychelles.

    Science.gov (United States)

    Stokes-Riner, Abbie; Thurston, Sally W; Myers, Gary J; Duffy, Emeir M; Wallace, Julie; Bonham, Maxine; Robson, Paula; Shamlaye, Conrad F; Strain, J J; Watson, Gene; Davidson, Philip W

    2011-01-01

    Maternal fish consumption during pregnancy exposes the fetus simultaneously to methylmercury (MeHg) and long chain polyunsaturated fatty acids (LCPUFA). Data from the Seychelles Child Development Nutrition Study (SCDNS) showed a negative association of MeHg with child development when children were 30 months of age, only when controlling for LCPUFA. Concomitantly, n-3 LCPUFA were found to have a significant positive association only at 9 months. These findings suggest that the effects of MeHg and LCPUFA may vary with age over the first few years of life. We address this by including outcomes at two ages and adjusting for the child's age at testing. A longitudinal analysis utilizing linear mixed models was performed to assess the associations of maternal hair total mercury (THg, a biomarker for MeHg) and maternal LCPUFA with children's Bayley Scales of Infant Development Psychomotor Developmental Index (BSID-II PDI) at 9 and 30 months of age, and to determine whether these associations change over time. Data from 228 children were included. Maternal hair MeHg had a negative effect on BSID PDI, while maternal n-3 LCPUFA had a positive effect. These effects did not change significantly from 9 to 30 months in this analysis. The longitudinal analysis provides increased power for estimating the relationships of prenatal MeHg and LCPUFA exposures during child development. Significant associations of these exposures in opposite directions confirm the importance of LCPUFA in development and the need to adjust for maternal nutrition when studying prenatal MeHg exposure. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. HPLC-ICP-MS speciation analysis of arsenic in urine of Japanese subjects without occupational exposure.

    Science.gov (United States)

    Hata, Akihisa; Endo, Yoko; Nakajima, Yoshiaki; Ikebe, Maiko; Ogawa, Masanori; Fujitani, Noboru; Endo, Ginji

    2007-05-01

    The toxicity and carcinogenicity of arsenic depend on its species. Individuals living in Japan consume much seafood that contains high levels of organoarsenics. Speciation analysis of urinary arsenic is required to clarify the health risks of arsenic intake. There has been no report of urinary arsenic analysis in Japan using high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). We performed speciation analysis of urinary arsenic for 210 Japanese male subjects without occupational exposure using HPLC-ICP-MS. The median values of urinary arsenics were as follows: sodium arsenite (AsIII), 3.5; sodium arsenate (AsV), 0.1; monomethylarsonic acid (MMA), 3.1; dimethylarsinic acid (DMA), 42.6; arsenobetaine (AsBe), 61.3; arsenocholine, trimethylarsine oxide, and unidentified arsenics (others), 5.2; and total arsenic (total As), 141.3 microgAs/l. The median creatinine-adjusted values were as follows: AsIII, 3.0; AsV, 0.1; MMA, 2.6; DMA, 35.9; AsBe, 52.1; others 3.5; and total As, 114.9 microgAs/g creatinine. Our findings indicate that DMA and AsBe levels in Japan are much higher than those found in Italian and American studies. It appears that the high levels of DMA and AsBe observed in Japan may be due in part to seafood intake. ACGIH and DFG set the BEI and BAT values for occupational arsenic exposure as 35 microgAs/l and 50 microgAs/l, respectively, using the sum of inorganic arsenic (iAs), MMA, and DMA. In the general Japanese population, the sums of these were above 50 microgAs/l in 115 (55%) samples. We therefore recommend excluding DMA concentration in monitoring of iAs exposure.

  6. Bronchoalveolar lavage analysis, gallium-67 lung scanning and soluble interleukin-2 receptor levels in asbestos exposure

    International Nuclear Information System (INIS)

    Delclos, G.L.; Flitcraft, D.G.; Brousseau, K.P.; Windsor, N.T.; Nelson, D.L.; Wilson, R.K.; Lawrence, E.C.

    1989-01-01

    This study examined different markers of lung immunologic and inflammatory responses to previous asbestos exposure. We performed bronchoalveolar lavage (BAL) and gallium-67 ( 67 Ga) lung scans and measured serum and BAL soluble interleukin-2 receptor (IL-2R) and angiotensin-converting enzyme (SACE) levels in 32 subjects with a history of significant asbestos exposure, 14 without (EXP) and 18 with (ASB) radiographic evidence of asbestosis. BAL analysis revealed increases in neutrophils in both ASB and EXP when compared to controls (P less than 0.01), which persisted after adjustment for smoking category. Although significant abnormalities of macrophage and total lymphocyte profiles were not found in the study population, lymphocyte subpopulation analysis revealed elevation of BAL T4/T8 ratios in the entire study group (ASB + EXP) when compared to controls (P less than 0.05), independent of smoking category. 67 Ga lung scan activity was increased in 56% of ASB and in 36% of EXP: no correlations between positive scans and different radiological and functional parameters could be found. There was no significant elevation of mean SACE, serum, or BAL IL-2R levels in any of the study categories. These data suggest that asbestos exposure may be associated with parenchymal inflammation, even in the absence of clinical criteria for asbestosis. Abnormalities of gallium uptake and of BAL analysis reflect the clinically inapparent inflammation. The increased BAL T4/T8 ratios observed suggest that abnormal local pulmonary immunoregulation may play a role in the pathogenesis of asbestos-related lung diseases

  7. Assessment of gold exposure and contamination in galvanizing workplace by neutron activation analysis

    International Nuclear Information System (INIS)

    Menezes, M.A.B.C.; Amaral, A.M.; Maia, E.C.P.; Albinati, C.C.B.

    2007-01-01

    Gold is not included in the current list of elements considered essential to humans and there are many controversies related to its toxicity. According to the chemical characteristics of the element, Au 1+ is favored for binding at sites with S donor, such as sulfhydryl group (-SH) in proteins in biological systems. This tendency raises the possibility of health-related risk, mainly linked to a long-term exposure to high and low levels of gold. This paper highlights the determination of gold by instrumental neutron activation analysis (INAA) during the assessment of exposure levels to metals and possible workers' contamination in three galvanizing factories applying the same processes. This assessment is aimed at giving support to Worker's Health Awareness Program of the Municipal Department of Health of Belo Horizonte, Minas Gerais, Brazil. INAA, mix of k 0 and monostandard methods was applied to air filter, hair and toenail samples, and to urine samples. Solvent extraction of gold was carried out followed by comparative INAA. The results revealed that gold was present in all matrixes, indicating the exposure in the workplace and suggesting endogenous contamination. Is gold playing a role as a toxic element? (author)

  8. Gene expression analysis in gonads and brain of catfish Clarias batrachus after the exposure of malathion.

    Science.gov (United States)

    Prathibha, Y; Murugananthkumar, R; Rajakumar, A; Laldinsangi, C; Sudhakumari, C C; Mamta, S K; Dutta-Gupta, A; Senthilkumaran, B

    2014-04-01

    Pesticides like malathion have the potential to disrupt development and reproduction of aquatic organisms including fishes. To investigate the likely consequences of malathion exposure at low doses in juvenile catfish, Clarias batrachus, we studied the expression pattern of genes encoding certain transcription factors, activin A, sex steroid or orphan nuclear receptors and steroidogenic enzymes which are known to be involved in gonadal development along with histological changes. To compare further, we also analyzed certain brain specific genes related to gonadal axis. Fifty days post hatch catfish fingerlings were exposed continuously to 1 and 10 µg/L of malathion for 21 days. Results from these experiments indicated that transcript levels of various genes were altered by the treatments, which may further affect the gonadal development either directly or indirectly through brain. Histological analysis revealed slow progression of spermatogenesis in testis, while in ovary, the oil droplet oocytes were found to be higher after treatment (10 µg/L). Our findings revealed that the exposure of malathion, even at low doses, hinder or modulate early gonadal development differentially by targeting gene expression pattern of transcription factors, activin A, sex steroid or orphan nuclear receptors and steroidogenic enzymes with an evidence on histological changes. Further, some of the genes showed differential expression at the level of brain in male and female sex after the exposure of malathion. Copyright © 2014. Published by Elsevier Inc.

  9. Development of three-dimensional shoulder kinematic and electromyographic exposure variation analysis methodology in violin musicians.

    Science.gov (United States)

    Reynolds, Jonathan F; Leduc, Robert E; Kahnert, Emily K; Ludewig, Paula M

    2014-01-01

    A total of 11 male and 19 female violinists performed 30-second random-ordered slow and fast musical repertoire while right shoulder three-dimensional kinematic, and upper trapezius and serratus anterior surface electromyography (EMG) data were summarised using exposure variation analysis (EVA), a bivariate distribution of work time spent at categories of signal amplitude, and duration spent at a fixed category of amplitude. Sixty-two per cent of intraclass correlation coefficients [1,1] for all kinematic and EMG variables exceeded 0.75, and 40% of standard error of the measurement results were below 5%, confirming EVA reliability. When fast repertoire was played, increases in odds ratios in short duration cells were seen in 23 of 24 possible instances, and decreases in longer duration cells were seen in 17 instances in all EVA arrays using multinomial logistic regression with random effects, confirming a shift towards shorter duration. A reliable technique to assess right shoulder kinematic and EMG exposure in violinists was identified. A reliable method of measuring right shoulder motion and muscle activity exposure variation in violinists was developed which can be used to assess ergonomic risk in other occupations. Recently developed statistical methods enabled differentiation between fast and slow musical performance of standardised musical repertoire.

  10. Dynamic exposure model analysis of continuous laser direct writing in Polar-coordinate

    Science.gov (United States)

    Zhang, Shan; Lv, Yingjun; Mao, Wenjie

    2018-01-01

    In order to exactly predict the continuous laser direct writing quality in Polar-coordinate, we take into consideration the effect of the photoresist absorbing beam energy, the Gaussian attribute of the writing beam and the dynamic exposure process, and establish a dynamic exposure model to describe the influence of the tangential velocity of the normal incident facular center and laser power on the line width and sidewall angle. Numerical simulation results indicate that while writing velocity remains unchanged, the line width and sidewall angle are all increased as the laser power increases; while laser power remains unchanged, the line width and sidewall angle are all decreased as the writing velocity increases; at the same time the line profile in the exposure section is asymmetry and the center of the line has tiny excursion toward the Polar-coordinate origin compared with the facular center. Then it is necessary to choose the right writing velocity and laser power to obtain the ideal line profile. The model makes up the shortcomings of traditional models that can only predict line width or estimate the profile of the writing line in the absence of photoresist absorption, and can be considered as an effect analysis method for optimizing the parameters of fabrication technique of laser direct writing.

  11. Transcriptomic analysis in the developing zebrafish embryo after compound exposure: Individual gene expression and pathway regulation

    Energy Technology Data Exchange (ETDEWEB)

    Hermsen, Sanne A.B., E-mail: Sanne.Hermsen@rivm.nl [Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, P.O. Box 616, 6200 MD, Maastricht (Netherlands); Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.178, 3508 TD, Utrecht (Netherlands); Pronk, Tessa E. [Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, P.O. Box 616, 6200 MD, Maastricht (Netherlands); Brandhof, Evert-Jan van den [Centre for Environmental Quality, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA Bilthoven (Netherlands); Ven, Leo T.M. van der [Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA Bilthoven (Netherlands); Piersma, Aldert H. [Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA Bilthoven (Netherlands); Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.178, 3508 TD, Utrecht (Netherlands)

    2013-10-01

    The zebrafish embryotoxicity test is a promising alternative assay for developmental toxicity. Classically, morphological assessment of the embryos is applied to evaluate the effects of compound exposure. However, by applying differential gene expression analysis the sensitivity and predictability of the test may be increased. For defining gene expression signatures of developmental toxicity, we explored the possibility of using gene expression signatures of compound exposures based on commonly expressed individual genes as well as based on regulated gene pathways. Four developmental toxic compounds were tested in concentration-response design, caffeine, carbamazepine, retinoic acid and valproic acid, and two non-embryotoxic compounds, D-mannitol and saccharin, were included. With transcriptomic analyses we were able to identify commonly expressed genes, which were mostly development related, after exposure to the embryotoxicants. We also identified gene pathways regulated by the embryotoxicants, suggestive of their modes of action. Furthermore, whereas pathways may be regulated by all compounds, individual gene expression within these pathways can differ for each compound. Overall, the present study suggests that the use of individual gene expression signatures as well as pathway regulation may be useful starting points for defining gene biomarkers for predicting embryotoxicity. - Highlights: • The zebrafish embryotoxicity test in combination with transcriptomics was used. • We explored two approaches of defining gene biomarkers for developmental toxicity. • Four compounds in concentration-response design were tested. • We identified commonly expressed individual genes as well as regulated gene pathways. • Both approaches seem suitable starting points for defining gene biomarkers.

  12. Occupational exposure to polychlorinated biphenyls and risk of cutaneous melanoma: a meta-analysis.

    Science.gov (United States)

    Boffetta, Paolo; Catalani, Simona; Tomasi, Cesare; Pira, Enrico; Apostoli, Pietro

    2018-01-01

    The aim of this study was to carry out a meta-analysis of studies on exposure to polychlorinated biphenyls (PCBs) and the risk of malignant melanoma (MM). We searched Scopus, PubMed, and reference lists; among 807 potentially relevant articles, we selected those based on 12 populations. Data were extracted according to a standardized form; the Newcastle-Ottawa Scale was used to assess study quality. Meta-analyses were carried out according to fixed-effect and random-effects models. The fixed-effect summary relative risk (RR) for MM was 0.91 [95% confidence interval (CI): 0.82-1.00]; the random-effects summary RR was 1.05 (95% CI: 0.78-1.32). The random-effects summary RR from eight occupational cohorts was 1.13 (95% CI: 0.91-1.35) and that from four community-based studies was 0.84 (95% CI: 0.36-1.31). The quality of the studies and the methods for PCB exposure assessment did not influence the RR. These results do not support the hypothesis of an association between PCB exposure and the risk of MM.

  13. Liquid chromatography-dopant-assisted atmospheric pressure photoionization-mass spectrometry: Application to the analysis of aldehydes in atmospheric aerosol particles.

    Science.gov (United States)

    Ruiz-Jiménez, José; Hautala, Sanna; Parshintsev, Jevgeni; Laitinen, Totti; Hartonen, Kari; Petäjä, Tuukka; Kulmala, Markku; Riekkola, Marja-Liisa

    2013-01-01

    A complete methodology based on LC-anisole-toluene dopant-assisted atmospheric pressure photoionization-IT-MS was developed for the determination of aldehydes in atmospheric aerosol particles. For the derivatization, ultrasound was used to accelerate the reaction between the target analytes and 2,4-dinitrophenylhydrazine. The developed methodology was validated for three different samples, gas phase, ultrafine (Dp = 30 ± 4 nm; where Dp stands for particle diameter) and all-sized particles, collected on Teflon filters. The method quantitation limits ranged from 5 to 227 pg. The accuracy and the potential matrix effects were evaluated using standard addition methodology. Recoveries ranged between 91.7 and 109.9%, and the repeatability and the reproducibility of the method developed between 0.5 and 8.0% and between 2.9 and 11.1%, respectively. The results obtained by the developed methodology compared to those provided by the previously validated method revealed no statistical differences. The method developed was applied to the determination of aldehydes in 16 atmospheric aerosol samples (30 nm and all-sized samples) collected at the Station for Measuring Forest Ecosystem-Atmosphere Relations II during spring 2011. The mean concentrations of aldehydes, and oxidation products of terpenes were between 0.05 and 82.70 ng/m(3). © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. The beryllium quandary: will the lower exposure limits spur new developments in sampling and analysis?

    Energy Technology Data Exchange (ETDEWEB)

    Brisson, Michael

    2013-06-03

    At the time this article was written, new rulemakings were under consideration at OSHA and the U.S. Department of Energy (DOE) that would propose changes to occupational exposure limits for beryllium. Given these developments, it’s a good time to review the tools and methods available to IHs for assessing beryllium air and surface contamination in the workplace—what’s new and different, and what’s tried and true. The article discusses limit values and action levels for beryllium, problematic aspects of beryllium air sampling, sample preparation, sample analysis, and data evaluation.

  15. Renal Effects and Carcinogenicity of Occupational Exposure to Uranium: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Leonhard Stammler

    2016-02-01

    Full Text Available Purpose: Uranium is a heavy metal with alpha radioactivity. We state the hypothesis that uranium exposure is harmful to human kidneys and carcinogenic to body tissues. Therefore, we review epidemiological studies from people with known long-lasting uranium exposure. Materials and Methods: Three meta-analyses are performed using clinical studies published in the PubMed database and applying RevMan 5.3 from the Cochrane Collaboration to calculate the outcome. The first two meta-analyses examine the standardized mortality ratio (SMR and the standardized incidence ratio for any cancers of uranium workers who were operating in areas ranging from uranium processing to the assembly of final uranium products. The third meta-analysis evaluates the nephrotoxic risk in uranium workers as well as soldiers and of individuals with exposure to drinking water containing uranium. Results: Overall and contrasting to our hypothesis, the tumor risk is significantly lower for uranium workers than for control groups (SMR = 0.90 with a 95% confidence interval of 0.84 to 0.96. In addition and also contrasting to our hypothesis, the risk of nephrotoxicity is not increased either. This holds for both the incidence and the mortality due to renal cell carcinoma or due to acute kidney injury or chronic kidney disease. In contrast, a significantly better creatinine clearance is found for the uranium cohort as compared to the control groups (mean difference = 7.66 with a 95% confidence interval of 0.12 to 15.2. Conclusion: Our hypothesis that a chronic uranium exposure is associated with an increased risk of cancer mortality or of kidney failure is refuted by clinical data. The decreased risk may result from better medical surveillance of uranium workers.

  16. Child Care Exposure Influences Childhood Adiposity at 2 Years: Analysis from the ROLO Study.

    Science.gov (United States)

    Scully, Helena; Alberdi, Goiuri; Segurado, Ricardo; McNamara, Aoife; Lindsay, Karen; Horan, Mary; Hennessy, Eilis; Gibney, Eileen; McAuliffe, Fionnuala

    2017-04-01

    The first 2 years of life are instrumental for childhood physical development. Factors contributing to childhood obesity are difficult to determine; child care exposure is one to consider, by influencing food preference and physical activity development. To investigate the association of child care exposure with adiposity at 2 years. Data were collected as part of the secondary analysis of the prospective ROLO study (randomized control trial of low glycemic index diet) in Dublin, Ireland. Mothers were recruited antenatally and followed up at 2 years postpartum. Maternal and childhood anthropometric data and lifestyle questionnaires, reporting on child care attendance (defined as nonparental care), exposure (weeks), and infant-feeding practices, were collected. Anthropometric measures and lifestyle data were collected for 273 mothers and children aged 2 years, 52.7% of whom attended child care. Child care was predominately provided by a nonrelative (83.7%), either in a crèche (57%) or by a childminder (26.7%). More than half (56.2%) of the children attended child care part-time (≤30 hours/week). Central adiposity measures (abdominal circumference, waist:height ratio) and total adiposity (sum of all skin folds) were significantly elevated in children with increasing time in child care. Children provided with "meals and snacks" had elevated adiposity measures versus those given "snacks or no food." No difference in the infant-feeding practices was identified between the child care groups. Children attending child care have higher total and central adiposity, proportional to exposure. More research is required to investigate this link to appropriately design health promotion and obesity prevention programs targeting children at 2 years.

  17. Top 100 Cited articles on Radiation Exposure in Medical Imaging: A Bibliometric Analysis.

    Science.gov (United States)

    Kinnin, Jason; Hanna, Tarek N; Jutras, Marc; Hasan, Babar; Bhatia, Rick; Khosa, Faisal

    2018-03-20

    Bibliometric analyses by highest number of citations can help researchers and funding agencies in determining the most influential articles in a field. The main objective of this analysis was to identify the top 100 cited articles addressing radiation exposure from medical imaging and assess their characteristics. Relevant articles were extracted from the Scopus database after a systematic search by researchers using an iteratively defined Boolean search string. Subsequently, exclusion criteria were applied. A list of top 100 articles was prepared, and articles were ranked according to the citations they had received. No time restriction was applied. Descriptive statistics of the data were compiled. The top-cited articles were published from 1970-2013, with the most articles published in 2009 and 2010 (12 articles in each year). The citations ranged from 107-1888 with a median of 272. Manuscripts from our top-cited list originated from 20 different countries, with contributions made by 158 authors and 160 organizations. Eighty-eight percent of studies evaluated patient-related radiation exposure, 7% health care workers, and 5% both or were not specified. Thirty-two percent of studies examined adult populations, 14% pediatric, and 54% included both populations or did not specify. Seventy-two percent of studies were dedicated to Computed Tomography, 8% to radiography/fluoroscopy, 9% to interventional procedures, 4% to nuclear medicine, and 7% to a combination of 2 or more modalities. The top 100 cited articles in medical imaging related to radiation exposure are diverse, originating from many countries with numerous contributing authors. The most common topics covered involve CT and adult patients. The recent peak in the most-highly cited articles (2010) suggests that increased attention has been devoted to this field in recent years. Based on these results, it would appear that research on radiation exposure in medical imaging is poised to continue expanding

  18. Final technical report: Atmospheric emission analysis for the Hanford Waste Vitrification plant

    International Nuclear Information System (INIS)

    Andrews, G.L.; Rhoads, K.C.

    1996-03-01

    This report is an assessment of chemical and radiological effluents that are expected to be released to the atmosphere from the Hanford Waste Vitrification Plant (HWVP). The report is divided into two sections. In the first section, the impacts of carbon monoxide (CO) and nitrogen oxides as NO 2 have been estimated for areas within the Hanford Site boundary. A description of the dispersion model used to-estimate CO and NO 2 average concentrations and Hanford Site meteorological data has been included in this section. In the second section, calculations were performed to estimate the potential radiation doses to a maximally exposed off-site individual. The model used to estimate the horizontal and vertical dispersion of radionuclides is also discussed

  19. Silicon etching of difluoromethane atmospheric pressure plasma jet combined with its spectroscopic analysis

    Science.gov (United States)

    Sung, Yu-Ching; Wei, Ta-Chin; Liu, You-Chia; Huang, Chun

    2018-06-01

    A capacitivly coupled radio-frequency double-pipe atmospheric-pressure plasma jet is used for etching. An argon carrier gas is supplied to the plasma discharge jet; and CH2F2 etch gas is inserted into the plasma discharge jet, near the silicon substrate. Silicon etchings rate can be efficiently-controlled by adjusting the feeding etching gas composition and plasma jet operating parameters. The features of silicon etched by the plasma discharge jet are discussed in order to spatially spreading plasma species. Electronic excitation temperature and electron density are detected by increasing plasma power. The etched silicon profile exhibited an anisotropic shape and the etching rate was maximum at the total gas flow rate of 4500 sccm and CH2F2 concentration of 11.1%. An etching rate of 17 µm/min was obtained at a plasma power of 100 W.

  20. Identification of elements in polutants of Mexico City's atmosphere, using the pixe analysis

    International Nuclear Information System (INIS)

    Diaz-Godoy, R.V.

    1990-01-01

    A review of the fundamentals and actual state in Mexico of the pixe (particle induced X- ray emission) technique are done. Elemental identification in samples of Mexico City's atmosphere taken in two sites is performed using this technique. A 3 MeV proton beam is used to irradiate the samples. Factors (Bremsstrahlung and interference) that difficult the use of the technique are discussed. The sensitivity of the method is enhanced as a main characteristic. It is shown that tje pixe technique together with an appropriate sampling system can be used to study environmental aerosols. Identified elements are bromine, lead, copper, iron, zinc, titanium, vanadium, calcium, potassium, chlorine, sulfur and silicon. Temporal variations of these elements are discussed. (Author)

  1. Temporal and spatial trends studied by lichen analysis: atmospheric deposition of trace elements in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Aspiazu, J.; Cervantes, L.; Ramirez, J.; Lopez, J.; Villasenor, P. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Ramos, R.; Munoz, R. [Secretaria del Medio Ambiente, Gestion Ambiental del Aire, Mexico City (Mexico)

    2007-07-01

    Ball moss on Tillandsia recurvata (Bromeliaceae), collected in an area previously identified as unpolluted, was transplanted to thirteen bio-monitoring sites in the downtown and metropolitan areas of Mexico City (which cover a surface of 9,560 km{sup 2}) during the periods August 2002 - January 2003 and July 2003 - October 2003. A total of 52 lichens (weighing 300 g) were transplanted to each place. Two were analysed as zero or reference, El Chico National Park, a location 100 Km upwind from the city and the remaining 26 were hung in nylon net bags in order to be able to collect two transplanted tree month, out of every season over a one-year period. The concentrations were measured by the quantitative PIXE method based on an extemal beam facility. The atmospheric deposition for trace elements was inferred by its concentration in lichen samples collected in 2002 from 13 sites in Mexico and compared with data from a similar survey in 2003. The concentration of Cr, Cu, Co, Fe, Mn, Ni, Pb and Zn and other elements was determined for each sample. Maps for each element were drawn after a geostatistical estimate of the metal concentration in the sample was made. Maps were drawn for all elements with the estimated values. Geographical distribution patterns were obtained for the different metals, reflecting the contribution of natural and anthropogenic emission sources. The deposition patterns of V, As, Se, Cd and Pb are substantially influenced by long-range transport from other parts of Mexico City. For Cr, Fe, Co, Ni, and Cu, the deposition patterns are largely determined by contribution from point sources within Mexico and in the metropolitan area. The lichen data for Br and, in part, Se reflect an airborne supply from the environment. Contributions to trace element concentrations in lichen sources other than atmospheric deposition are identified and discussed. The Spatial and temporal variations in the distribution of metal concentration are discussed. (Author)

  2. Temporal and spatial trends studied by lichen analysis: atmospheric deposition of trace elements in Mexico

    International Nuclear Information System (INIS)

    Aspiazu, J.; Cervantes, L.; Ramirez, J.; Lopez, J.; Villasenor, P.; Ramos, R.; Munoz, R.

    2007-01-01

    Ball moss on Tillandsia recurvata (Bromeliaceae), collected in an area previously identified as unpolluted, was transplanted to thirteen bio-monitoring sites in the downtown and metropolitan areas of Mexico City (which cover a surface of 9,560 km 2 ) during the periods August 2002 - January 2003 and July 2003 - October 2003. A total of 52 lichens (weighing 300 g) were transplanted to each place. Two were analysed as zero or reference, El Chico National Park, a location 100 Km upwind from the city and the remaining 26 were hung in nylon net bags in order to be able to collect two transplanted tree month, out of every season over a one-year period. The concentrations were measured by the quantitative PIXE method based on an extemal beam facility. The atmospheric deposition for trace elements was inferred by its concentration in lichen samples collected in 2002 from 13 sites in Mexico and compared with data from a similar survey in 2003. The concentration of Cr, Cu, Co, Fe, Mn, Ni, Pb and Zn and other elements was determined for each sample. Maps for each element were drawn after a geostatistical estimate of the metal concentration in the sample was made. Maps were drawn for all elements with the estimated values. Geographical distribution patterns were obtained for the different metals, reflecting the contribution of natural and anthropogenic emission sources. The deposition patterns of V, As, Se, Cd and Pb are substantially influenced by long-range transport from other parts of Mexico City. For Cr, Fe, Co, Ni, and Cu, the deposition patterns are largely determined by contribution from point sources within Mexico and in the metropolitan area. The lichen data for Br and, in part, Se reflect an airborne supply from the environment. Contributions to trace element concentrations in lichen sources other than atmospheric deposition are identified and discussed. The Spatial and temporal variations in the distribution of metal concentration are discussed. (Author)

  3. Analysis of Co, Cr and Mn Concentrations in Atmospheric Dry Deposition in Hamadan City

    Directory of Open Access Journals (Sweden)

    P. Shokri Ragheb

    2016-07-01

    Full Text Available Introduction & Objective: Heavy metals are major pollutants that can spread in the atmosphere with particulate matter and dust and because of the toxic and carcinogenic effects, their meas-urement and control is very important. Therefore, this study was conducted to assess Co, Cr and Mn concentration in the atmospheric dry deposition collected from Hamadan city in 2014. Materials & Methods: After collection of 12 dust samples from 3 sampling stations and their laboratory preparation, metals concentrations were determined using ICP–OES. All statistical analyses were performed using the SPSS statistical package. Results: The results showed that the minimum and maximum mean concentrations of Co were 0.19 and 0.29 mg/kg for high and low traffic intensity sampling stations, respectively. The min and max mean concentrations of Cr were 0.65and 1.02 mg/kg for high traffic intensity and suburb sampling stations, respectively and the min and max mean concentrations of Mn were 7.23and 8.82 mg/kg for high and low traffic intensity sampling stations , respectively. Also comparing the mean concentrations of assessed metals with WHO permissible limits showed a significant difference (P< 0.05. The mean concentrations of metals were signifi-cantly lower than the maximum permissible limits. Conclusion: Although the mean concentrations of Co, Cr and Mn are lower than the standard levels, lack of continuous monitoring of heavy metals concentrations in the dust and particu-late matters in the air can lead to the entrance of various types of toxic pollutants such as heavy metals into the air and result in adverse health effects. (Sci J Hamadan Univ Med Sci 2016; 23 (2:149-156

  4. Feasibility of gas chromatography-microchip atmospheric pressure photoionization-mass spectrometry in analysis of anabolic steroids.

    Science.gov (United States)

    Hintikka, Laura; Haapala, Markus; Franssila, Sami; Kuuranne, Tiia; Leinonen, Antti; Kostiainen, Risto

    2010-12-24

    Mass spectrometers equipped with atmospheric pressure ion sources (API-MS) have been designed to be interfaced with liquid chromatographs (LC) and have rarely been connected to gas chromatographs (GC). Recently, we introduced a heated nebulizer microchip and showed its potential to interface liquid microseparation techniques and GC with API-MS. This study demonstrates the feasibility of GC-microchip atmospheric pressure photoionization-tandem mass spectrometry (GC-μAPPI-MS/MS) in the analysis of underivatized anabolic steroids in urine. The APPI microchip provides high ionization efficiency and produces abundant protonated molecules or molecular ions with minimal fragmentation. The feasibility of GC-μAPPI-MS/MS in the analysis of six selected anabolic steroids in urine samples was studied with respect to intra-batch repeatability, linearity, linear range, and limit of detection (LOD). The method showed good sensitivity (LODs 0.2-1 ng/mL), repeatability (relative standard deviationanabolic steroids. Quantitative performance of the method was tested with two authentic urine samples, and the results were in good agreement with those obtained with conventional GC-electron ionization-MS after derivatization. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Paternal exposure to Agent Orange and spina bifida: a meta-analysis

    International Nuclear Information System (INIS)

    Ngo, Anh Duc; Taylor, Richard; Roberts, Christine L.

    2010-01-01

    The objective of this study is to conduct a meta-analysis of published and unpublished studies that examine the association between Agent Orange (AO) exposure and the risk of spina bifida. Relevant studies were identified through a computerized literature search of Medline and Embase from 1966 to 2008; a review of the reference list of retrieved articles and conference proceedings; and by contacting researchers for unpublished studies. Both fixed-effects and random-effects models were used to pool the results of individual studies. The Cochrane Q test and index of heterogeneity (I 2 ) were used to evaluate heterogeneity, and a funnel plot and Egger's test were used to evaluate publication bias. Seven studies, including two Vietnamese and five non-Vietnamese studies, involving 330 cases and 134,884 non-cases were included in the meta-analysis. The overall relative risk (RR) for spina bifida associated with paternal exposure to AO was 2.02 (95% confidence interval [CI]: 1.48-2.74), with no statistical evidence of heterogeneity across studies. Non-Vietnamese studies showed a slightly higher summary RR (RR = 2.22; 95% CI: 1.38-3.56) than Vietnamese studies (RR = 1.92 95% CI: 1.29-2.86). When analyzed separately, the overall association was statistically significant for the three case-control studies (Summary Odds Ratio = 2.25, 95% CI: 1.31-3.86) and the cross sectional study (RR = 1.97, 95% CI: 1.31-2.96), but not for the three cohort studies (RR: 2.11; 95% CI: 0.78-5.73). Paternal exposure to AO appears to be associated with a statistically increased risk of spina bifida.

  6. Analysis of Patients' X-ray Exposure in 146 Percutaneous Radiologic Gastrostomies.

    Science.gov (United States)

    Petersen, Tim-Ole; Reinhardt, Martin; Fuchs, Jochen; Gosch, Dieter; Surov, Alexey; Stumpp, Patrick; Kahn, Thomas; Moche, Michael

    2017-09-01

    Purpose  Analysis of patient´s X-ray exposure during percutaneous radiologic gastrostomies (PRG) in a larger population. Materials and Methods  Data of primary successful PRG-procedures, performed between 2004 and 2015 in 146 patients, were analyzed regarding the exposition to X-ray. Dose-area-product (DAP), dose-length-product (DLP) respectively, and fluoroscopy time (FT) were correlated with the used x-ray systems (Flatpanel Detector (FD) vs. Image Itensifier (BV)) and the necessity for periprocedural placement of a nasogastric tube. Additionally, the effective X-ray dose for PRG placement using fluoroscopy (DL), computed tomography (CT), and cone beam CT (CBCT) was estimated using a conversion factor. Results  The median DFP of PRG-placements under fluoroscopy was 163 cGy*cm 2 (flat panel detector systems: 155 cGy*cm 2 ; X-ray image intensifier: 175 cGy*cm 2 ). The median DLZ was 2.2 min. Intraprocedural placement of a naso- or orogastric probe (n = 68) resulted in a significant prolongation of the median DLZ to 2.5 min versus 2 min in patients with an already existing probe. In addition, dose values were analyzed in smaller samples of patients in which the PRG was placed under CBCT (n = 7, median DFP = 2635 cGy*cm 2 ), or using CT (n = 4, median DLP = 657 mGy*cm). Estimates of the median DFP and DLP showed effective doses of 0.3 mSv for DL-assisted placements (flat panel detector 0.3 mSv, X-ray image converter 0.4 mSv), 7.9 mSv using a CBCT - flat detector, and 9.9 mSv using CT. This corresponds to a factor 26 of DL versus CBCT, or a factor 33 of DL versus CT. Conclusion  In order to minimize X-ray exposure during PRG-procedures for patients and staff, fluoroscopically-guided interventions should employ flat detector systems with short transmittance sequences in low dose mode and with slow image frequency. Series recordings can be dispensed with. The intraprocedural placement of a naso- or orogastric probe

  7. Use of principal components analysis and three-dimensional atmospheric-transport models for reactor-consequence evaluation

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Walton, J.J.; Alpert, D.J.; Johnson, J.D.

    1982-01-01

    This work explores the use of principal components analysis coupled to three-dimensional atmospheric transport and dispersion models for evaluating the environmental consequences of reactor accidents. This permits the inclusion of meteorological data from multiple sites and the effects of topography in the consequence evaluation; features not normally included in such analyses. The technique identifies prevailing regional wind patterns and their frequencies for use in the transport and dispersion calculations. Analysis of a hypothetical accident scenario involving a release of radioactivity from a reactor situated in a river valley indicated the technique is quite useful whenever recurring wind patterns exist, as is often the case in complex terrain situations. Considerable differences were revealed in a comparison with results obtained from a more conventional Gaussian plume model using only the reactor site meteorology and no topographic effects

  8. Analysis of those national analytic epidemiological studies that by obtention the exposure-response functions

    International Nuclear Information System (INIS)

    Molina, E.; Meneses, E.

    2003-01-01

    The Impact Pathway methodology, developed in the frame of Extern E project for estimating of the external costs or externalities of the energy use, has as one of their main steps the health impact evaluation. This evaluation is carried out through exposure-response functions. In previous estimates of the external costs of power generation in Cuba, functions obtained in international studies were used. The main objective of this work was to carry out a summarized critical analysis of those national analytic epidemiological studies that, according the exposed methodology, consider the main aspects specialized with views to the possible preliminary proposal of functions exposure-response (FER) based own in epidemiologic evidences. In agreement with the analysis, the results show that the great majority of the studies are not useful for the FER establishment, at least in their present form. A minority studies exists that contributes limited evidence and their reanalysis could increase their contribution to the propose purpose. Finally the main problems found in the studies are enumerated revision object

  9. Quantitative analysis of untreated human nails for monitoring human exposure to heavy metals

    International Nuclear Information System (INIS)

    Sera, Koichiro; Futatsugawa, Shouji; Murao, Satoshi; Clemente, E.

    2002-01-01

    In order to address global environmental issues, a standard-free method developed by ourselves has been successfully applied to various kinds of bio-samples. Especially, a method for untreated hairs has been applied in many polluted areas to study human exposure to toxic elements. In addition to hair, nail is expected to give us valuable information about human exposure to toxic elements. However, the analysis requires relatively large amounts of samples and laborious sample preparation techniques which necessitate internal standards. In this work, we have developed a quantitative method for untreated human-nail analysis based on the standard-free method. It requires neither large amounts of nails nor complicated target preparation procedure. Furthermore, it is perfectly free from any ambiguity in target preparation such as volatilization of certain elements and contamination of the sample during chemical ashing. The optimum conditions of irradiating nail samples are established, and accuracy and reproducibility of the present method are confirmed. It is found that ultrasonic washing in distilled water is effective for many nail samples preventing the loss of elements from the sample. It is also found that elemental concentration in nails strongly depends on their sampling positions. (author)

  10. Cytogenetic analysis in peripheral blood lymphocytes after arteriography (exposure to X-rays and contrast medium)

    International Nuclear Information System (INIS)

    Hadjidekova, V.; Popova, L.; Hristova, R.; Hadjidekov, V.

    2006-01-01

    Full text: The purpose of our study is to investigate the cytogenetic effects in peripheral blood lymphocytes of 29 patients who had undergone diagnostic angiography. Peripheral blood samples were taken from 22 patients submitted to renal arteriography and 7 patients submitted to cerebral arteriography (17 male and 12 female, aged between 13 and 68 years). Cytogenetic analysis was performed in peripheral lymphocytes before the procedure, immediately after and 24 hours later. The entrance skin dose obtained during the whole diagnostic X-ray exposure was measured by thermoluminescent dosimeters and varied between 0.03 - 0.30 Gy. Both low and high osmolarity contrast media were used. Chromosomal aberrations and micronuclei frequency was used as biomarkers of genotoxicity. The estimated frequency of chromosomal aberrations and micronuclei in peripheral blood lymphocytes of patients after arteriography examination is significantly higher than the level before the diagnostic exposure. The mean frequency of cells with chromosomal aberrations nearly double after examination and remained constant at 24h analysis. Radiological diagnostic procedures involving iodinated contrast media as arteriography may cause a significant increase of the cytogenetic injury in peripheral blood lymphocytes

  11. Cytogenetic analysis of peripheral blood lymphocytes after arteriography (exposure to x-rays and contrast medium)

    International Nuclear Information System (INIS)

    Popova, L.; Hadjidekova, V.; Karadjov, G.; Agova, S.; Traskov, D.; Hadjidekov, V.

    2005-01-01

    Backgrounds. The purpose of our study is to investigate the cytogenetic analysis findings in peripheral blood lymphocytes of 29 patients who had undergone diagnostic radiography. Methods. Peripheral blood samples were taken from 22 patients submitted to renal arteriography and 7 patients submitted to cerebral arteriography (17 male and 12 female, aged between 13-68 years). Cytogenetic analyses of peripheral lymphocytes were performed before the procedure, immediately after and 24 hours later. The entrance skin dose obtained during the whole diagnostic X-ray exposure was measured by thermoluminescent dosimeters and varied between 0.03-0.30 Gy. Both low and high osmolarity contrast media were used. Chromosomal aberrations and micronuclei frequency were used as biomarkers of genotoxicity. Results. The estimated frequency of chromosomal aberrations and micronuclei in the peripheral blood lymphocytes of patients after arteriography examination was significantly higher than the level before the diagnostic exposure. The mean frequency of cells with chromosomal aberrations was nearly double after examination and proved to be constant in the analysis after 24 hours. Conclusions. Radiological diagnostic procedures involving iodinated contrast media as arteriography may cause a significant increase in cytogenetic damage in peripheral blood lymphocytes. (author)

  12. Oscillations in stellar atmospheres

    International Nuclear Information System (INIS)

    Costa, A.; Ringuelet, A.E.; Fontenla, J.M.

    1989-01-01

    Atmospheric excitation and propagation of oscillations are analyzed for typical pulsating stars. The linear, plane-parallel approach for the pulsating atmosphere gives a local description of the phenomenon. From the local analysis of oscillations, the minimum frequencies are obtained for radially propagating waves. The comparison of the minimum frequencies obtained for a variety of stellar types is in good agreement with the observed periods of the oscillations. The role of the atmosphere in the globar stellar pulsations is thus emphasized. 7 refs

  13. A meta-analysis of exposure to particulate matter and adverse birth outcomes

    Directory of Open Access Journals (Sweden)

    Dirga Kumar Lamichhane

    2015-11-01

    Full Text Available Objectives The objective of this study was to conduct a systematic review to provide summarized evidence on the association between maternal exposure to particulate air pollution and birth weight (BW and preterm birth (PTB after taking into consideration the potential confounding effect of maternal smoking. Methods We systematically searched all published cohort and case-control studies examining BW and PTB association with particulate matter (PM, less than or equal to 2.5μm and 10.0 μm in diameter, PM2.5 and PM10, respectively from PubMed and Web of Science, from January 1980 to April 2015. We extracted coefficients for continuous BW and odds ratio (OR for PTB from each individual study, and meta-analysis was used to combine the coefficient and OR of individual studies. The methodological quality of individual study was assessed using a standard protocol proposed by Downs and Black. Forty-four studies met the inclusion criteria. Results In random effects meta-analyses, BW as a continuous outcome was negativelyassociated with 10 μg/m3 increase in PM10 (-10.31 g; 95% confidence interval [CI], -13.57 to -3.13 g; I-squared=0%, p=0.947 and PM2.5 (-22.17 g; 95% CI, -37.93 to -6.41 g; I-squared=92.3%, p <0.001 exposure during entire pregnancy, adjusted for maternal smoking. A significantly increased risk of PTB per 10 μg/m3 increase in PM10 (OR, 1.23; 95% CI, 1.04 to 1.41; I-squared=0%, p =0.977 and PM2.5 (OR, 1.14; 95% CI, 1.06 to 1.22; I-squared=92.5%, p <0.001 exposure during entire pregnancy was observed. Effect size of change in BW per 10 μg/m3 increase in PM tended to report stronger associations after adjustment for maternal smoking. Conclusions While this systematic review supports an adverse impact of maternal exposure to particulate air pollution on birth outcomes, variation in effects by exposure period and sources of heterogeneity between studies should be further explored.

  14. The risk of hearing loss associated with occupational exposure to organic solvents mixture with and without concurrent noise exposure: A systematic review and meta-analysis.

    Science.gov (United States)

    Hormozi, Maryam; Ansari-Moghaddam, Alireza; Mirzaei, Ramazan; Dehghan Haghighi, Javid; Eftekharian, Fatemeh

    2017-06-19

    This study is a meta-analysis of the previous epidemiological studies which investigated the quantitative estimates of the association between independent or combined exposure to noise and mixed organic solvents and hearing loss until October 2014. Overall, 15 studies with information on 7530 individuals (6% female) were included. Having assessed - by puretone audiometry - the adjusted odds ratio estimates for the association between solvents mixture exposure and the risk of developing hearing loss stood at 2.05 (95% confidence interval (CI): 1.44-2.9). Similarly, for subjects who were concurrently exposed to noise and solvents mixture, an OR of 2.95 (95% CI: 2.1-4.17) was obtained. There was some evidence of heterogeneity within each of the 2 exposure groups (p heterogeneity hearing loss for workers exposed to organic solvents even at quite low concentration. Moreover, if such exposure is accompanied by noise, it will exacerbate the extent of hearing loss. Int J Occup Med Environ Health 2017;30(4):521-535. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  15. SPR sen