WorldWideScience

Sample records for base present contamination

  1. Remediation of the Andreyev Bay naval base; present contamination status and future monitoring strategy

    International Nuclear Information System (INIS)

    Hustveit, Styrkaar; Sneve, Malgorzata K.; Reistad, Ole; Kiselev, Mikhail; Shandala, Natalya

    2008-01-01

    Full text: The Andreyev Bay shore technical base (STB) is a former naval installation and the largest nuclear legacy site in northwest Russia. Established in the late 50-ties and early 60-ties, this naval facility performed activities related to the refuelling of Soviet Northern Fleet nuclear-propelled vessels as well as being a temporary storage site for SNF and solid and liquid radioactive wastes (SRW and LRW) arising as a result of civilian and military nuclear-propelled vessels operations and maintenance. A large inventory of spent nuclear fuel (SNF) and radioactive waste (RAW) are located at the site, and since an accident in 1982 large amounts of radioactivity have been released from the storage facilities. Remediation of Andreyev STB has been the subject of international cooperation for many years. Great Britain, Italy, Norway, Sweden and the European Bank for Reconstruction and Development (EBRD) have collaborated with the Russian government to secure the site, improve the infrastructure at the site, plan for new management strategies/facilities for SNF and demolish old buildings that were deemed an environmental hazard. On the basis of an agreement between the Russian Federal State Enterprise 'SevRao' and the Norwegian Radiation Protection Authority (NRPA) a study to map the gamma dose rates and the surface radionuclide concentrations in the contaminated parts of the site, as well as an overview and general knowledge of the area regarding geological and hydrogeological conditions was performed in the period 2002-2004. The aim of the study was to enable the provision of more effective radiological protection for personnel undertaking future operations at the site and to assess the radiation dose hazards present at Andreyev STB and to clarify the risks associated with the existing contamination and the continued storage of spent fuel and radioactive waste at the site. The first phase of the Norwegian program to survey the Andreyev Bay provided the basis for

  2. Radioactive contamination in Arctic - present situation and future challenges

    International Nuclear Information System (INIS)

    Strand, Per

    2002-01-01

    There is currently a focus on radioactivity and the Arctic region. The reason for this is probably the high number of nuclear sources in parts of the Arctic and the vulnerability of Arctic systems to radioactive contamination. The Arctic environment is also perceived as a wilderness and the need for the protection of this wilderness against contamination is great. In the last decade information has also been released concerning the nuclear situation which has caused concern in many countries. Due to such concerns, the International Arctic Environmental Protection Strategy (IAEPS) was launched in 1991 and the Arctic Monitoring and Assessment Programme (AMAP) was established. AMAP is undertaking an assessment of the radioactive contamination of the Arctic and its radiological consequences. In 1996 IAEPS became part of the Arctic Council. AMAP presented one main report in 1997 and another in 1998. There are also several other national, bilateral and international programmes in existence which deal with this issue. This paper summarises some of current knowledge about sources of radioactive contamination, vulnerability, exposure of man, and potential sources for radioactive contamination within Arctic and some views on the future needs for work concerning radioactivity in Arctic. (au)

  3. Present level of contaminants in the Romanian Black Sea sector

    International Nuclear Information System (INIS)

    Bologa, A.S.; Apas, M.; Cociasu, A.; Cuingioglu, E.; Patrascu, V.; Pecheanu, I.; Piescu, V.; Popa, L.

    1999-01-01

    The assessment of environmental quality in the Romanian Black Sea sector is being constantly made by the Romanian Marine Research Institute (RMRI) within the National Integrated Monitoring System. The contamination of the marine environment is expressed by considering four chemical and a biological parameter: nutrients (N-NO 2 , N-NO 3 , N-NH 4 , P-PO 4 , organic P, Si-SiO 4 ), heavy metals (Mn, Fe, Cu, Cd, Pb), artificial radionuclides ( 90 Sr, 137 Cs), total hydrocarbons, parasite and saprophyte fungi in sediments, sea water and/or biota. Present levels of contaminants are discussed as to their historical evolution during the last few years or decades. Inorganic N and P concentrations still exceed three to five times those before eutrophication started to intensify in the early '70s. Practical uses of results by national and regional authorities are discussed. (author)

  4. Radioactive contamination in the Arctic - Present situation and future challenges

    International Nuclear Information System (INIS)

    Strand, P.

    2002-01-01

    There is currently a focus on radioactivity and the Arctic region. The reason for this is the high number of nuclear sources in parts of the Arctic and the vulnerability of Arctic systems to radioactive contamination. The Arctic environment is also perceived as a wilderness and the need for the protection of this wilderness against contamination is great. In 1991, the International Arctic Environmental Protection Strategy (IAEPS) was launched and the Arctic Monitoring and Assessment Programme (AMAP) established. AMAP is undertaking an assessment of the radioactive contamination of the Arctic and its radiological consequences. This paper summarises some of current knowledge about sources of radioactive contamination, vulnerability, exposure of man, and potential sources for radioactive contamination within Arctic and some views on the future needs for work concerning radioactivity in Arctic. (author)

  5. Field based plastic contamination sensing

    Science.gov (United States)

    The United States has a long-held reputation of being a dependable source of high quality, contaminant-free cotton. Recently, increased incidence of plastic contamination from sources such as shopping bags, vegetable mulch, surface irrigation tubing, and module covers has threatened the reputation o...

  6. Contamination of wines and spirits by phthalates: types of contaminants present, contamination sources and means of prevention.

    Science.gov (United States)

    Chatonnet, P; Boutou, S; Plana, A

    2014-01-01

    This research determines the concentrations of various phthalates in French wines and grape spirits marketed in Europe or intended for export. Dibutyl phthalate (DBP), diethylhexyl phthalate (DEHP) and butyl benzyl phthalate (BBP) were the most frequently detected compounds in the wines analysed. While only 15% of the samples examined contained quantifiable concentrations (> 0.010 mg kg(-1)) of DEHP and BBP, 59% of the wines contained significant quantities of DBP, with a median value as high as 0.0587 mg kg(-1). Only 17% of the samples did not contain any detectable quantity of at least one of the phthalates and 19% contained only non-quantifiable traces. In the spirits analysed, DBP (median = 0.105 mg kg(-1)) and DEHP (median = 0.353 mg kg(-1)) were the substances measured at the highest concentrations, as well as the most frequently detected (90% of samples). BBP was present in 40% of the samples at an average concentration of 0.026 mg kg(-1). Di-isobutyl phthalate (DiBP), which is not permitted in contact with food, was found in 25% of the spirits tested. According to the specific migration limits (SML) for materials in contact with food, slightly more than 11% of the wines analysed were non-compliant, as they exceeded the SML for DBP (0.3 mg kg(-1)); just under 4% were close to the SML for DEHP. Concerning spirits, 19% of the samples analysed were considered non-compliant to the SML for DBP and nearly 7% were close to the SML for DEHP. The aged grape spirits analysed were often excessively contaminated with DiBP, which is not permitted to be used in contact with food (> 0.01 mg kg(-1)). A study of various materials frequently present in wineries revealed that a relatively large number of polymers sometimes contained high concentrations of phthalates. However, the epoxy resin coatings used on vats represented the major source of contamination.

  7. Satellite Contamination and Materials Outgassing Knowledge base

    Science.gov (United States)

    Minor, Jody L.; Kauffman, William J. (Technical Monitor)

    2001-01-01

    Satellite contamination continues to be a design problem that engineers must take into account when developing new satellites. To help with this issue, NASA's Space Environments and Effects (SEE) Program funded the development of the Satellite Contamination and Materials Outgassing Knowledge base. This engineering tool brings together in one location information about the outgassing properties of aerospace materials based upon ground-testing data, the effects of outgassing that has been observed during flight and measurements of the contamination environment by on-orbit instruments. The knowledge base contains information using the ASTM Standard E- 1559 and also consolidates data from missions using quartz-crystal microbalances (QCM's). The data contained in the knowledge base was shared with NASA by government agencies and industry in the US and international space agencies as well. The term 'knowledgebase' was used because so much information and capability was brought together in one comprehensive engineering design tool. It is the SEE Program's intent to continually add additional material contamination data as it becomes available - creating a dynamic tool whose value to the user is ever increasing. The SEE Program firmly believes that NASA, and ultimately the entire contamination user community, will greatly benefit from this new engineering tool and highly encourages the community to not only use the tool but add data to it as well.

  8. Integrating Individual-Based Indices of Contaminant Effects

    Directory of Open Access Journals (Sweden)

    Christopher L. Rowe

    2001-01-01

    Full Text Available Habitat contamination can alter numerous biological processes in individual organisms. Examining multiple individual-level responses in an integrative fashion is necessary to understand how individual health or fitness reflects environmental contamination. Here we provide an example of such an integrated perspective based upon recent studies of an amphibian (the bullfrog, Rana catesbeiana that experiences several, disparate changes when larval development occurs in a trace element�contaminated habitat. First, we present an overview of studies focused on specific responses of individuals collected from, or transplanted into, a habitat contaminated by coal combustion residues (CCR. These studies have reported morphological, behavioral, and physiological modifications to individuals chronically interacting with sediments in the CCR-contaminated site. Morphological abnormalities in the oral and tail regions in contaminant-exposed individuals influenced other properties such as grazing, growth, and swimming performance. Behavioral changes in swimming activities and responses to stimuli appear to influence predation risk in the contaminant-exposed population. Significant changes in bioenergetics in the contaminated habitat, evident as abnormally high energetic expenditures for survival (maintenance costs, may ultimately influence production pathways (growth, energy storage in individuals. We then present a conceptual model to examine how interactions among the affected systems (morphological, behavioral, physiological may ultimately bring about more severe effects than would be predicted if the responses were considered in isolation. A complex interplay among simultaneously occurring biological changes emerges in which multiple, sublethal effects ultimately can translate into reductions in larval or juvenile survival, and thus reduced recruitment of juveniles into the population. In systems where individuals are exposed to low concentrations of

  9. Emerging contaminants: Presentations at the 2009 Toxicology and Risk Assessment Conference

    International Nuclear Information System (INIS)

    Murnyak, George; Vandenberg, John; Yaroschak, Paul J.; Williams, Larry; Prabhakaran, Krishnan; Hinz, John

    2011-01-01

    A session entitled 'Emerging Contaminants' was held in April 2009 in Cincinnati, OH at the 2009 Toxicology and Risk Assessment Conference. The purpose of the session was to share information on both programmatic and technical aspects associated with emerging contaminants. Emerging contaminants are chemicals or materials that are characterized by a perceived or real threat to human health or environment, a lack of published health standards or an evolving standard. A contaminant may also be 'emerging' because of the discovery of a new source, a new pathway to humans, or a new detection method or technology. The session included five speakers representing the Department of Defense (DoD), the Environmental Protection Agency (EPA), and each of the military services. The DoD created the Emerging Contaminant Directorate to proactively address environmental, health, and safety concerns associated with emerging contaminants. This session described the scan-watch-action list process, impact assessment methodology, and integrated risk management concept that DoD has implemented to manage emerging contaminants. EPA presented emerging trends in health risk assessment. Researchers made technical presentations on the status of some emerging contaminates in the assessment process (i.e. manganese, RDX, and naphthalene).

  10. Contaminant classification using cosine distances based on multiple conventional sensors.

    Science.gov (United States)

    Liu, Shuming; Che, Han; Smith, Kate; Chang, Tian

    2015-02-01

    Emergent contamination events have a significant impact on water systems. After contamination detection, it is important to classify the type of contaminant quickly to provide support for remediation attempts. Conventional methods generally either rely on laboratory-based analysis, which requires a long analysis time, or on multivariable-based geometry analysis and sequence analysis, which is prone to being affected by the contaminant concentration. This paper proposes a new contaminant classification method, which discriminates contaminants in a real time manner independent of the contaminant concentration. The proposed method quantifies the similarities or dissimilarities between sensors' responses to different types of contaminants. The performance of the proposed method was evaluated using data from contaminant injection experiments in a laboratory and compared with a Euclidean distance-based method. The robustness of the proposed method was evaluated using an uncertainty analysis. The results show that the proposed method performed better in identifying the type of contaminant than the Euclidean distance based method and that it could classify the type of contaminant in minutes without significantly compromising the correct classification rate (CCR).

  11. The role of packaging size on contamination rates during simulated presentation to a sterile field.

    Directory of Open Access Journals (Sweden)

    Tony Trier

    Full Text Available The objective of this study was to assess the impact of package size on the contact between medical devices and non-sterile surfaces (i.e. the hands of the practitioner and the outside of the package during aseptic presentation to a simulated sterile field. Rationale for this objective stems from the decades-long problem of hospital-acquired infections. This work approaches the problem from a unique perspective, namely packaging size.Randomized complete block design with subsampling.Research study conducted at professional conferences for surgical technologists and nursing professionals.Ninety-seven healthcare providers, primarily surgical technologists and nurses.Participants were gloved and asked to present the contents of six pouches of three different sizes to a simulated sterile field. The exterior of pouches and gloves of participants were coated with a simulated contaminant prior to each opening trial. After presentation to the simulated sterile field, the presence of the contaminant on package contents was recorded as indicative of contact with non-sterile surfaces and analyzed in a binary fashion using a generalized linear mixed model.Recruited subjects were 26-64 years of age (81 females, 16 males, with 2.5-44 years of professional experience. Results indicated a significant main effect of pouch size on contact rate of package contents (P = 0.0108, whereby larger pouches induced greater rates of contact than smaller pouches (estimates±SEM: 14.7±2.9% vs. 6.0±1.7%, respectively.This study utilized novel methodologies which simulate contamination in aseptic presentation. Results of this work indicate that increased contamination rates are associated with larger pouches when compared to smaller pouches. The results add to a growing body of research which investigate packaging's role in serving as a pathway for product contamination during aseptic presentation. Future work should investigate other packaging design factors (e

  12. Cloud Based Applications and Platforms (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Brodt-Giles, D.

    2014-05-15

    Presentation to the Cloud Computing East 2014 Conference, where we are highlighting our cloud computing strategy, describing the platforms on the cloud (including Smartgrid.gov), and defining our process for implementing cloud based applications.

  13. Presentation planning using an integrated knowledge base

    Science.gov (United States)

    Arens, Yigal; Miller, Lawrence; Sondheimer, Norman

    1988-01-01

    A description is given of user interface research aimed at bringing together multiple input and output modes in a way that handles mixed mode input (commands, menus, forms, natural language), interacts with a diverse collection of underlying software utilities in a uniform way, and presents the results through a combination of output modes including natural language text, maps, charts and graphs. The system, Integrated Interfaces, derives much of its ability to interact uniformly with the user and the underlying services and to build its presentations, from the information present in a central knowledge base. This knowledge base integrates models of the application domain (Navy ships in the Pacific region, in the current demonstration version); the structure of visual displays and their graphical features; the underlying services (data bases and expert systems); and interface functions. The emphasis is on a presentation planner that uses the knowledge base to produce multi-modal output. There has been a flurry of recent work in user interface management systems. (Several recent examples are listed in the references). Existing work is characterized by an attempt to relieve the software designer of the burden of handcrafting an interface for each application. The work has generally focused on intelligently handling input. This paper deals with the other end of the pipeline - presentations.

  14. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  15. Limits determination of microbial contamination present on surfaces from a pharmaceutical microbiology district reference laboratory

    Directory of Open Access Journals (Sweden)

    Natalia Charry

    2016-06-01

    Full Text Available Context: The bioburden present on the pharmaceutical microbiology laboratory’s surfaces, may increase the risk of cross-contamination when analytical tests are being carried out; periodic monitoring allows to set limits that reduce the risk. Aims: To determinate the limits of bioburden present on seven surfaces of the pharmaceutical microbiology laboratory, after the cleaning and disinfection process. Methods: The swabbing method was used for sampling. With a 25 cm2 stencil and a sterile swab, a sample was taken, passing the swab over five points of every surface chosen. A total aerobic microbial count and a total yeast and mold count was done. Finally, the average and the standard deviation of the counts was obtained. Results: The average from the counts obtained on each surface selected for the study, were below the recommended limits by international entities like the World Health Organization and the European Union, between others; also, the results generated in this study, allow to classify the biosafety cabinet as an ISO 5 area and the other areas as ISO 7. Conclusions: Bioburden levels on the tested surfaces are considered low, reducing the risk of cross-contamination, which could have a negative impact on laboratory’s activities. Also, it follows that disinfectant concentration used, is effectively.

  16. Transuranic contaminated waste container characterization and data base. Revision I

    International Nuclear Information System (INIS)

    Kniazewycz, B.G.

    1980-05-01

    The Nuclear Regulatory Commission (NRC) is developing regulations governing the management, handling and disposal of transuranium (TRU) radioisotope contaminated wastes as part of the NRC's overall waste management program. In the development of such regulations, numerous subtasks have been identified which require completion before meaningful regulations can be proposed, their impact evaluated and the regulations implemented. This report was prepared to assist in the development of the technical data base necessary to support rule-making actions dealing with TRU-contaminated wastes. An earlier report presented the waste sources, characteristics and inventory of both Department of Energy (DOE) generated and commercially generated TRU waste. In this report a wide variety of waste sources as well as a large TRU inventory were identified. The purpose of this report is to identify the different packaging systems used and proposed for TRU waste and to document their characteristics. This document then serves as part of the data base necessary to complete preparation and initiate implementation of TRU waste container and packaging standards and criteria suitable for inclusion in the present TRU waste management program. It is the purpose of this report to serve as a working document which will be used as appropriate in the TRU Waste Management Program. This report, and those following, will be compatible not only in format, but also in reference material and direction

  17. Synthesis of present methods of surface contamination detection (skin, clothes, laboratories)

    International Nuclear Information System (INIS)

    Joudrier, P.

    1983-01-01

    The signification of the term ''contamination'' is briefly recalled. To measure the levels of contamination, there are only two methods: the direct method and the indirect method. Finally, the recent improvements in the surface contamination detection field are shortly reviewed [fr

  18. Levels of contamination for various pollutants present in Belgian human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Wouwe, N. Van; Goeyens, L. [Scientific Inst. of Public Health, Brussels (Belgium); Covaci, A. [Toxicological Center, Univ. of Antwerp, Wilrijk (Belgium); Kannan, K. [Wadsworth Center, New York State Dept. of Health, Albany, NY (United States); Gordon, J.; Chu, A. [Xenobiotic Detection System Inc., Durham, NC (United States); Eppe, G.; Pauw, E. De [Center of Analysis of residues in Traces (CART), Univ. of Liege (Belgium)

    2004-09-15

    During the last century, numerous compounds, such as polychlorinated biphenyls (PCBs) or organochlorine pesticides (OCPs), were banned because of their bioaccumulative and toxic properties, while other compounds, such as polybrominated diphenyl ethers (PBDEs), appeared on the market and consequently in the environment. The experiences gained from accidents involving PBBs, PCBs or PCDD/Fs are useful to conduct scientific investigations focused on preventing similar catastrophies with the newly introduced compounds. Several studies have reported potential increase in the concentration of PBDEs in food and wildlife. Monitoring the levels of toxic chemicals is therefore useful to understand the exposure pathways, sources and trends. The aim of the paper is to present actual contamination's levels of various pollutants in human plasma from Belgium. Several classes of pollutants, such PCDD/Fs, PCBs and OCPs were determined in 20 human plasmas. In addition, perfluorooctanesulfonate (PFOS) and related fluorochemicals, which are of current concern, were measured. Although anticipated, concentrations of PBDEs in the same samples were not yet determined. Through this study, a good approximation of the contamination level in Belgian human is given, allowing thus comparison with concentrations observed in other countries.

  19. ContaMiner and ContaBase: a webserver and database for early identification of unwantedly crystallized protein contaminants

    Science.gov (United States)

    Hungler, Arnaud; Momin, Afaque; Diederichs, Kay; Arold, Stefan, T.

    2016-01-01

    Solving the phase problem in protein X-ray crystallography relies heavily on the identity of the crystallized protein, especially when molecular replacement (MR) methods are used. Yet, it is not uncommon that a contaminant crystallizes instead of the protein of interest. Such contaminants may be proteins from the expression host organism, protein fusion tags or proteins added during the purification steps. Many contaminants co-purify easily, crystallize and give good diffraction data. Identification of contaminant crystals may take time, since the presence of the contaminant is unexpected and its identity unknown. A webserver (ContaMiner) and a contaminant database (ContaBase) have been established, to allow fast MR-based screening of crystallographic data against currently 62 known contaminants. The web-based ContaMiner (available at http://strube.cbrc.kaust.edu.sa/contaminer/) currently produces results in 5 min to 4 h. The program is also available in a github repository and can be installed locally. ContaMiner enables screening of novel crystals at synchrotron beamlines, and it would be valuable as a routine safety check for ‘crystallization and preliminary X-ray analysis’ publications. Thus, in addition to potentially saving X-ray crystallographers much time and effort, ContaMiner might considerably lower the risk of publishing erroneous data. PMID:27980519

  20. ContaMiner and ContaBase: a webserver and database for early identification of unwantedly crystallized protein contaminants

    KAUST Repository

    Hungler, Arnaud; Momin, Afaque Ahmad Imtiyaz; Diederichs, Kay; Arold, Stefan T.

    2016-01-01

    Solving the phase problem in protein X-ray crystallography relies heavily on the identity of the crystallized protein, especially when molecular replacement (MR) methods are used. Yet, it is not uncommon that a contaminant crystallizes instead of the protein of interest. Such contaminants may be proteins from the expression host organism, protein fusion tags or proteins added during the purification steps. Many contaminants co-purify easily, crystallize and give good diffraction data. Identification of contaminant crystals may take time, since the presence of the contaminant is unexpected and its identity unknown. A webserver (ContaMiner) and a contaminant database (ContaBase) have been established, to allow fast MR-based screening of crystallographic data against currently 62 known contaminants. The web-based ContaMiner (available at http://strube.cbrc.kaust.edu.sa/contaminer/) currently produces results in 5 min to 4 h. The program is also available in a github repository and can be installed locally. ContaMiner enables screening of novel crystals at synchrotron beamlines, and it would be valuable as a routine safety check for 'crystallization and preliminary X-ray analysis' publications. Thus, in addition to potentially saving X-ray crystallographers much time and effort, ContaMiner might considerably lower the risk of publishing erroneous data. A web server, titled ContaMiner, has been established, which allows fast molecular-replacement-based screening of crystallographic data against a database (ContaBase) of currently 62 potential contaminants. ContaMiner enables systematic screening of novel crystals at synchrotron beamlines, and it would be valuable as a routine safety check for 'crystallization and preliminary X-ray analysis' publications. © Arnaud Hungler et al. 2016.

  1. ContaMiner and ContaBase: a webserver and database for early identification of unwantedly crystallized protein contaminants

    KAUST Repository

    Hungler, Arnaud

    2016-11-02

    Solving the phase problem in protein X-ray crystallography relies heavily on the identity of the crystallized protein, especially when molecular replacement (MR) methods are used. Yet, it is not uncommon that a contaminant crystallizes instead of the protein of interest. Such contaminants may be proteins from the expression host organism, protein fusion tags or proteins added during the purification steps. Many contaminants co-purify easily, crystallize and give good diffraction data. Identification of contaminant crystals may take time, since the presence of the contaminant is unexpected and its identity unknown. A webserver (ContaMiner) and a contaminant database (ContaBase) have been established, to allow fast MR-based screening of crystallographic data against currently 62 known contaminants. The web-based ContaMiner (available at http://strube.cbrc.kaust.edu.sa/contaminer/) currently produces results in 5 min to 4 h. The program is also available in a github repository and can be installed locally. ContaMiner enables screening of novel crystals at synchrotron beamlines, and it would be valuable as a routine safety check for \\'crystallization and preliminary X-ray analysis\\' publications. Thus, in addition to potentially saving X-ray crystallographers much time and effort, ContaMiner might considerably lower the risk of publishing erroneous data. A web server, titled ContaMiner, has been established, which allows fast molecular-replacement-based screening of crystallographic data against a database (ContaBase) of currently 62 potential contaminants. ContaMiner enables systematic screening of novel crystals at synchrotron beamlines, and it would be valuable as a routine safety check for \\'crystallization and preliminary X-ray analysis\\' publications. © Arnaud Hungler et al. 2016.

  2. Aflatoxin contamination of locallyprocessed cereal-based ...

    African Journals Online (AJOL)

    Feeding children with cereal-based foods has potential to expose them to aflatoxins (AFs).This study was conducted to determine the occurrence and levels of aflatoxins (AFB1, AFB2, AFG1 and AFG2) in 64 commercial locally produced cereal-based complementary foods obtained from producers and popular markets in ...

  3. Special RADMIL report. Assessment of the past and present implications of radioactive contamination of Lancashire

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The county of Lancashire in the United Kingdom has a unique relationship with the nuclear industry in respect of the number of nuclear facilities within or close to its boundaries. This special Radiation Monitoring in Lancashire (RADMIL) report collates data collected from 1976 to 1994 to provide a dose reconstruction for that period. It is shown that the radiation exposure of the population of Lancashire has decreased over the past twenty years. This has been due largely to a decrease in the authorised discharges from the facilities at Sellafield. Despite the fact that the advisory public dose limits have been reduced fivefold over the period, the dose to the most exposed groups has been consistently below those limits. Present contamination of the Lancashire environment is much reduced by comparison with earlier years. The accumulated effect of past discharges will mean that little further improvement can be expected, however. Similarly, dose levels to the populations are also expected to remain steady unless discharges increase again. This data compilation will form a baseline against which RADMIL can compare the results of future monitoring. (17 figures, 38 tables, 182 references) (UK).

  4. Special RADMIL report. Assessment of the past and present implications of radioactive contamination of Lancashire

    International Nuclear Information System (INIS)

    1996-10-01

    The county of Lancashire in the United Kingdom has a unique relationship with the nuclear industry in respect of the number of nuclear facilities within or close to its boundaries. This special Radiation Monitoring in Lancashire (RADMIL) report collates data collected from 1976 to 1994 to provide a dose reconstruction for that period. It is shown that the radiation exposure of the population of Lancashire has decreased over the past twenty years. This has been due largely to a decrease in the authorised discharges from the facilities at Sellafield. Despite the fact that the advisory public dose limits have been reduced fivefold over the period, the dose to the most exposed groups has been consistently below those limits. Present contamination of the Lancashire environment is much reduced by comparison with earlier years. The accumulated effect of past discharges will mean that little further improvement can be expected, however. Similarly, dose levels to the populations are also expected to remain steady unless discharges increase again. This data compilation will form a baseline against which RADMIL can compare the results of future monitoring. (17 figures, 38 tables, 182 references) (UK)

  5. Present situation of radioactive contamination in and around the former Soviet Union's Semipalatinsk nuclear test site

    International Nuclear Information System (INIS)

    Yamamoto, M.; Hoshi, M.; Takada, J.; Tsukatani, T.; Oikawa, S.; Yoshikawa, I.; Takatsuji, T.; Sekerbaev, A. Kh.; Gusev, B.I.

    2001-01-01

    Field missions were sent to the Semipalatinsk regions to investigate the present radioecological situation as a result of the radioactive fallout from nuclear test explosions carried out at the former Soviet Union's Semipalatinsk nuclear test site (SNTS). For this purpose, surface and core soil samples were collected at more than 60 sites, including several settlements such as Dolon, Chagan and Sarzhal, within and outside the SNTS territory. The radioactivities of long-lived radionuclides, 137 Cs, 238 Pu and 239,240 Pu, and the atomic ratio of 240 Pu/ 239 Pu were determined in combination with non-destructive g-ray spectrometric method and radiochemical separation followed by a-particle spectrometric and/or ICP-MS methods. The results showed a distinction of 137 Cs and 239,240 Pu inventories in soil depending on a sampling sites. Although 137 Cs was within typical environmental levels except for the area near the first nuclear test site and Balapan, 239,240 Pu was at elevated levels in all areas we visited. This high Pu contamination was recognized to be due to the weapons-grade Pu from the SNTS by the measurement of 240 Pu/ 239P u atomic ratio in soil samples. (author)

  6. Modeling uranium transport in acidic contaminated groundwater with base addition

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan [Institute of Tibetan Plateau Research, Chinese Academy of Sciences; Luo, Wensui [ORNL; Parker, Jack C. [University of Tennessee, Knoxville (UTK); Brooks, Scott C [ORNL; Watson, David B [ORNL; Jardine, Philip [University of Tennessee, Knoxville (UTK); Gu, Baohua [ORNL

    2011-01-01

    This study investigates reactive transport modeling in a column of uranium(VI)-contaminated sediments with base additions in the circulating influent. The groundwater and sediment exhibit oxic conditions with low pH, high concentrations of NO{sub 3}{sup -}, SO{sub 4}{sup 2-}, U and various metal cations. Preliminary batch experiments indicate that additions of strong base induce rapid immobilization of U for this material. In the column experiment that is the focus of the present study, effluent groundwater was titrated with NaOH solution in an inflow reservoir before reinjection to gradually increase the solution pH in the column. An equilibrium hydrolysis, precipitation and ion exchange reaction model developed through simulation of the preliminary batch titration experiments predicted faster reduction of aqueous Al than observed in the column experiment. The model was therefore modified to consider reaction kinetics for the precipitation and dissolution processes which are the major mechanism for Al immobilization. The combined kinetic and equilibrium reaction model adequately described variations in pH, aqueous concentrations of metal cations (Al, Ca, Mg, Sr, Mn, Ni, Co), sulfate and U(VI). The experimental and modeling results indicate that U(VI) can be effectively sequestered with controlled base addition due to sorption by slowly precipitated Al with pH-dependent surface charge. The model may prove useful to predict field-scale U(VI) sequestration and remediation effectiveness.

  7. Modeling uranium transport in acidic contaminated groundwater with base addition

    International Nuclear Information System (INIS)

    Zhang Fan; Luo Wensui; Parker, Jack C.; Brooks, Scott C.; Watson, David B.; Jardine, Philip M.; Gu Baohua

    2011-01-01

    This study investigates reactive transport modeling in a column of uranium(VI)-contaminated sediments with base additions in the circulating influent. The groundwater and sediment exhibit oxic conditions with low pH, high concentrations of NO 3 - , SO 4 2- , U and various metal cations. Preliminary batch experiments indicate that additions of strong base induce rapid immobilization of U for this material. In the column experiment that is the focus of the present study, effluent groundwater was titrated with NaOH solution in an inflow reservoir before reinjection to gradually increase the solution pH in the column. An equilibrium hydrolysis, precipitation and ion exchange reaction model developed through simulation of the preliminary batch titration experiments predicted faster reduction of aqueous Al than observed in the column experiment. The model was therefore modified to consider reaction kinetics for the precipitation and dissolution processes which are the major mechanism for Al immobilization. The combined kinetic and equilibrium reaction model adequately described variations in pH, aqueous concentrations of metal cations (Al, Ca, Mg, Sr, Mn, Ni, Co), sulfate and U(VI). The experimental and modeling results indicate that U(VI) can be effectively sequestered with controlled base addition due to sorption by slowly precipitated Al with pH-dependent surface charge. The model may prove useful to predict field-scale U(VI) sequestration and remediation effectiveness.

  8. Modeling uranium transport in acidic contaminated groundwater with base addition

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Fan, E-mail: zhangfan@itpcas.ac.cn [Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085 (China); Luo Wensui [Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China); Parker, Jack C. [Institute for a Secure and Sustainable Environment, Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Brooks, Scott C.; Watson, David B. [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Jardine, Philip M. [Biosystems Engineering and Soil Science Department, University of Tennessee, Knoxville, TN 37996 (United States); Gu Baohua [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2011-06-15

    This study investigates reactive transport modeling in a column of uranium(VI)-contaminated sediments with base additions in the circulating influent. The groundwater and sediment exhibit oxic conditions with low pH, high concentrations of NO{sub 3}{sup -}, SO{sub 4}{sup 2-}, U and various metal cations. Preliminary batch experiments indicate that additions of strong base induce rapid immobilization of U for this material. In the column experiment that is the focus of the present study, effluent groundwater was titrated with NaOH solution in an inflow reservoir before reinjection to gradually increase the solution pH in the column. An equilibrium hydrolysis, precipitation and ion exchange reaction model developed through simulation of the preliminary batch titration experiments predicted faster reduction of aqueous Al than observed in the column experiment. The model was therefore modified to consider reaction kinetics for the precipitation and dissolution processes which are the major mechanism for Al immobilization. The combined kinetic and equilibrium reaction model adequately described variations in pH, aqueous concentrations of metal cations (Al, Ca, Mg, Sr, Mn, Ni, Co), sulfate and U(VI). The experimental and modeling results indicate that U(VI) can be effectively sequestered with controlled base addition due to sorption by slowly precipitated Al with pH-dependent surface charge. The model may prove useful to predict field-scale U(VI) sequestration and remediation effectiveness.

  9. Inkjet-based adaptive planarization (Conference Presentation)

    Science.gov (United States)

    Singhal, Shrawan; Grigas, Michelle M.; Khusnatdinov, Niyaz; Sreenivasan, Srinivasan V.

    2017-03-01

    that should have been polished away. Preventive techniques like dummy fill and patterned resist can be used to reduce the variation in pattern density. These techniques increase the complexity of the planarization process and significantly limit the device design flexibility. Contact Planarization (CP) has also been reported as an alternative to the CMP processing [7], [8]. A substrate is spin coated with a photo curable material and pre baked to remove residual solvent. An ultra-flat surface or an optical flat is pressed on the spin-coated wafer. The material is forced to reflow. Pressure is used to spread out material evenly and achieve global planarization. The substrate is then exposed to UV radiation to harden the photo curable material. Although attractive, this process is not adaptive as it does not account for differences in surface topography of the wafer and the optical flat, nor can it address all the parasitics that arise during the process itself. The optical flat leads to undesirable planarization of even the substrate nominal shape and nanotopography, which corrupts the final film thickness profile. Hence, it becomes extremely difficult to eliminate this signature to a desirable extent without introducing other parasitic signatures. An example of this is shown in Figure 1. In this paper, a novel adaptive planarization process has been presented that potentially addresses the problems associated with planarization of varying pattern density, even in the presence of pre-existing substrate topography [9]. This process is called Inkjet-enabled Adaptive Planarization (IAP). The IAP process uses an inverse optimization scheme, built around a validated fluid mechanics-based forward model [10], that takes the pre-existing substrate topography and pattern layout as inputs. It then generates an inkjet drop pattern with a material distribution that is correlated with the desired planarization film profile. This allows a contiguous film to be formed with the desired

  10. Present status of contamination monitoring at the Dalat Nuclear Research Institute (DNRI)

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Hoang Van [Dalat Nuclear Research Inst. (Viet Nam)

    1997-06-01

    The Dalat nuclear research reactor was renovated and upgraded from the previous TRIGA reactor. In Vietnam, it is a unique nuclear device having suitable neutron flux for the radioisotope production and neutron activation analysis. Soon after the reactor reached its initial criticality in November 1983, a programme has been formed to develop the application of nuclear techniques in various fields. In addition, the use of radioisotopes for diagnostic, therapeutic and other research purposes has been in progress. In order to support these activities, the radiation protection, especially the radiation contamination monitoring has been properly paid attention to. In DNRI, the Radiation Protection Department is responsible for controlling and supervising radiation and working safety for all activities. In this paper, the following items are described on radiation contamination monitoring: controlled area, surface contamination monitoring, and airborne concentration monitoring. (G.K.)

  11. Wireless Sensor Network Based Subsurface Contaminant Plume Monitoring

    Science.gov (United States)

    2012-04-16

    Sensor Network (WSN) to monitor contaminant plume movement in naturally heterogeneous subsurface formations to advance the sensor networking based...time to assess the source and predict future plume behavior. This proof-of-concept research aimed at demonstrating the use of an intelligent Wireless

  12. Present status of Accelerator-Based BNCT.

    Science.gov (United States)

    Kreiner, Andres Juan; Bergueiro, Javier; Cartelli, Daniel; Baldo, Matias; Castell, Walter; Asoia, Javier Gomez; Padulo, Javier; Suárez Sandín, Juan Carlos; Igarzabal, Marcelo; Erhardt, Julian; Mercuri, Daniel; Valda, Alejandro A; Minsky, Daniel M; Debray, Mario E; Somacal, Hector R; Capoulat, María Eugenia; Herrera, María S; Del Grosso, Mariela F; Gagetti, Leonardo; Anzorena, Manuel Suarez; Canepa, Nicolas; Real, Nicolas; Gun, Marcelo; Tacca, Hernán

    2016-01-01

    This work aims at giving an updated report of the worldwide status of Accelerator-Based BNCT (AB-BNCT). There is a generalized perception that the availability of accelerators installed in hospitals, as neutron sources, may be crucial for the advancement of BNCT. Accordingly, in recent years a significant effort has started to develop such machines. A variety of possible charged-particle induced nuclear reactions and the characteristics of the resulting neutron spectra are discussed along with the worldwide activity in suitable accelerator development. Endothermic (7)Li(p,n)(7)Be and (9)Be(p,n)(9)B and exothermic (9)Be(d,n)(10)B are compared. In addition to having much better thermo-mechanical properties than Li, Be as a target leads to stable products. This is a significant advantage for a hospital-based facility. (9)Be(p,n)(9)B needs at least 4-5 MeV bombarding energy to have a sufficient yield, while (9)Be(d,n)(10)B can be utilized at about 1.4 MeV, implying the smallest possible accelerator. This reaction operating with a thin target can produce a sufficiently soft spectrum to be viable for AB-BNCT. The machines considered are electrostatic single ended or tandem accelerators or radiofrequency quadrupoles plus drift tube Linacs. (7)Li(p,n)(7)Be provides one of the best solutions for the production of epithermal neutron beams for deep-seated tumors. However, a Li-based target poses significant technological challenges. Hence, Be has been considered as an alternative target, both in combination with (p,n) and (d,n) reactions. (9)Be(d,n)(10)B at 1.4 MeV, with a thin target has been shown to be a realistic option for the treatment of deep-seated lesions.

  13. THE SCENARIOS APPROACH TO ATTENUATION-BASED REMEDIES FOR INORGANIC AND RADIONUCLIDE CONTAMINANTS

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K.; Rysz, M.; Truex, M.; Brady, P.; Newell, C.; Denham, M.

    2011-08-04

    Guidance materials based on use of conceptual model scenarios were developed to assist evaluation and implementation of attenuation-based remedies for groundwater and vadose zones contaminated with inorganic and radionuclide contaminants. The Scenarios approach is intended to complement the comprehensive information provided in the US EPA's Technical Protocol for Monitored Natural Attenuation (MNA) of Inorganic Contaminants by providing additional information on site conceptual models and extending the evaluation to consideration of Enhanced Attenuation approaches. The conceptual models incorporate the notion of reactive facies, defined as units with hydrogeochemical properties that are different from surrounding units and that react with contaminants in distinct ways. The conceptual models also incorporate consideration of biogeochemical gradients, defined as boundaries between different geochemical conditions that have been induced by waste disposal or other natural phenomena. Gradients can change over time when geochemical conditions from one area migrate into another, potentially affecting contaminant mobility. A recognition of gradients allows the attenuation-affecting conditions of a site to be projected into the future. The Scenarios approach provides a stepwise process to identify an appropriate category of conceptual model and refine it for a specific site. Scenario materials provide links to pertinent sections in the EPA technical protocol and present information about contaminant mobility and important controlling mechanism for attenuation-based remedies based on the categories of conceptual models.

  14. Chemical contamination of groundwater at gas processing plants - the past, the present and the future

    International Nuclear Information System (INIS)

    Wrubleski, R.M.; Drury, C.R.

    1997-01-01

    The chemicals used to remove the sour gas components (primarily H 2 S) from raw gas in the sour gas sweetening processes were discussed. The chemicals, mainly amines and physical absorbents, have been found as contaminants in soil and groundwater at several sites. Studies have been conducted to evaluate the behaviour of some of these chemicals. In particular, the contamination by sulfolane and diisopropanolamine (DIPA) which originate from the Sulfinol R sweetening process, was discussed. Prior to the mid 1970s wastes from these processes were disposed of on site in landfills that were not engineered for groundwater protection. By the mid 1970s the landfills were closed by capping. Many of the gas plant sites were located on elevated terrain where hydraulic gradient was available for downward movement of groundwater and any chemicals contained within. Contaminant movement in fractured bedrock has also affected drinking water. Ground water monitoring began in the mid 1980s to address environmental concerns, focusing on monitoring for potability, metals and organics. It was discovered that most of the plants using the Sulfinol process had groundwater contaminated with sulfolane levels ranging from 1 ppm to over 800 ppm. A research project was developed to determine the soil interaction parameters and biodegradation behaviour of pure sulfolane and DIPA to provide data in order to predict plume migration. Ecotoxicity tests were also performed to verify toxicity effects of sulfolane, DIPA, reclaimer bottoms and observed biodegradation metabolites to bio-organisms and aquatic life in aquatic receptors. 3 refs., 1 tab., 1 fig

  15. Present state of the monitoring for internal contamination at Tokai Research Establishment, Japan Atomic Energy Research Institute

    International Nuclear Information System (INIS)

    Akaishi, J.; Fukuda, H.; Mizushita, S.

    1980-01-01

    At Tokai Research Establishment, JAERI, over one thousand people work in hot areas such as reactors, accelerators, chemical laboratories and waste treatment plants. The monitoring for internal contamination of this personnel is presented. Routine and special monitoring are carried out. The object of the former is to check for the presence of significant contamination, and that of the latter is to estimate body burden and committed dose equivalent, if necessary. Heavy shield and shadow shield whole body counters, a low energy lung counter and a wound monitor are used to detect the internal contamination due to γ or chi ray emitters, and bioassay technique is used for α or β emitters and uranium. The results of the monitoring until now are presented. (H.K.)

  16. Cadmium contamination in cereal-based diets and diet ingredients

    International Nuclear Information System (INIS)

    Siitonen, P.H.; Thompson, H.C. Jr.

    1990-01-01

    Cereal-based diet and/or diet ingredient cadmium levels were determined by graphite furnace AAS. Cadmium contamination was 88.3 and 447 ppb in two cereal-based diets, 44.6 and 48.9 ppb in two purified diets, and ranged from less than 1.1 to 22,900 ppb in the ingredients of one cereal-based diet. The major source of cadmium contamination was attributed to the calcium supplement used for diet formulation. Comparative analyses of two purified diet samples and one cereal-based diet by the National Institute of Standards and Technology (NIST, formerly the National Bureau of Standards) and the National Center for Toxicological Research (NCTR) gave virtually identical results for Cd. A comparative study of Cd levels determined by flame and furnace AAS was also made by the NCTR and the NIST

  17. Waste Contaminants at Military Bases Working Group report

    International Nuclear Information System (INIS)

    1993-01-01

    The Waste Contaminants at Military Bases Working Group has screened six prospective demonstration projects for consideration by the Federal Advisory Committee to Develop On-Site Innovative Technologies (DOIT). These projects include the Kirtland Air Force Base Demonstration Project, the March Air Force Base Demonstration Project, the McClellan Air Force Base Demonstration Project, the Williams Air Force Base Demonstration Project, and two demonstration projects under the Air Force Center for Environmental Excellence. A seventh project (Port Hueneme Naval Construction Battalion Center) was added to list of prospective demonstrations after the September 1993 Working Group Meeting. This demonstration project has not been screened by the working group. Two additional Air Force remediation programs are also under consideration and are described in Section 6 of this document. The following information on prospective demonstrations was collected by the Waste Contaminants at Military Bases Working Group to assist the DOIT Committee in making Phase 1 Demonstration Project recommendations. The remainder of this report is organized into seven sections: Work Group Charter's mission and vision; contamination problems, current technology limitations, and institutional and regulatory barriers to technology development and commercialization, and work force issues; screening process for initial Phase 1 demonstration technologies and sites; demonstration descriptions -- good matches;demonstration descriptions -- close matches; additional candidate demonstration projects; and next steps

  18. Chemical contamination of groundwater at gas processing plants - the past, the present and the future

    Energy Technology Data Exchange (ETDEWEB)

    Wrubleski, R.M.; Drury, C.R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre; Sevigny, J.H. [Komex Consultants Ltd., Calgary, AB (Canada)

    1997-12-31

    The chemicals used to remove the sour gas components (primarily H{sub 2}S) from raw gas in the sour gas sweetening processes were discussed. The chemicals, mainly amines and physical absorbents, have been found as contaminants in soil and groundwater at several sites. Studies have been conducted to evaluate the behaviour of some of these chemicals. In particular, the contamination by sulfolane and diisopropanolamine (DIPA) which originate from the Sulfinol{sup R} sweetening process, was discussed. Prior to the mid 1970s wastes from these processes were disposed of on site in landfills that were not engineered for groundwater protection. By the mid 1970s the landfills were closed by capping. Many of the gas plant sites were located on elevated terrain where hydraulic gradient was available for downward movement of groundwater and any chemicals contained within. Contaminant movement in fractured bedrock has also affected drinking water. Ground water monitoring began in the mid 1980s to address environmental concerns, focusing on monitoring for potability, metals and organics. It was discovered that most of the plants using the Sulfinol process had groundwater contaminated with sulfolane levels ranging from 1 ppm to over 800 ppm. A research project was developed to determine the soil interaction parameters and biodegradation behaviour of pure sulfolane and DIPA to provide data in order to predict plume migration. Ecotoxicity tests were also performed to verify toxicity effects of sulfolane, DIPA, reclaimer bottoms and observed biodegradation metabolites to bio-organisms and aquatic life in aquatic receptors. 3 refs., 1 tab., 1 fig.

  19. Oxidative stress induced on Cyprinus carpio by contaminants present in the water and sediment of Madin Reservoir.

    Science.gov (United States)

    Galar-Martinez, Marcela; Gomez-Olivan, Leobardo Manuel; Amaya-Chavez, Araceli; Razo-Estrada, Celene; Garcia-Medina, Sandra

    2010-01-01

    Madin Reservoir (MR), located in the State of Mexico, is fed mainly by the Rio Tlalnepantla. MR supplies potable water to the municipalities of Naucalpan and Atizapan, and various recreational activities take place in its vicinity, such as sailing and the fishing of diverse species including the common carp Cyprinus carpio. The purpose of this study was to determine the toxic effects of contaminants present in MR water and sediment on C. carpio. Five sampling stations were selected (those considered to have the most problems due to discharges). Water and sediment samples were taken and toxicity studies were performed, including acute toxicity (lethality) and subacute toxicity assays. The biomarkers used in the subacute assays were lipid peroxidation (LPX) and activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in the liver and brain of test organisms. These biomarkers were also evaluated in local carp, i.e. carp with chronic exposure in situ to reservoir contaminants. Results show that contaminants in the water and sediment of the different sampling stations induce oxidative stress, this toxicity being more evident in samples from stations near the entry point of the Rio Tlalnepantla tributary and in local carp. This may be due to high contaminant levels as well as the fact that the physicochemical characteristics of the matrices might favor their bioavailability. Thus, both the water and sediment of this reservoir are contaminated with xenobiotics hazardous to C. carpio, a species consumed by the local human population.

  20. Present state of the monitoring for internal contamination at Tokai Research Establishment, Japan Atomic Energy Research Institute

    International Nuclear Information System (INIS)

    Akaishi, J.; Fukuda, H.; Mizushita, S.

    1980-01-01

    Results are presented of internal contamination surveys carried out since 1969 at Tokai Research Establishment. Routine monitoring sometimes revealed significant internal contamination for tritium workers, but almost never for others. The number of subjects for special monitoring varied according to the activities. In 1965, the number of subjects for special monitoring was nearly 300, due to a reactor repair that year. In recent years, the number or special monitoring has been several tens or so. With regard to special monitoring, the workers with significant internal contamination were less than 50%. The internal dose (50 years) estimated for the majority of subjects was of mrem order. During the past 15 years, only several cases of exposure of rem order were found. The highest dose experienced was about 4 rems ( 131 I thyroid) (U.K.)

  1. A comprehensive guide of remediation technologies for oil contaminated soil - Present works and future directions.

    Science.gov (United States)

    Lim, Mee Wei; Lau, Ee Von; Poh, Phaik Eong

    2016-08-15

    Oil spills result in negative impacts on the environment, economy and society. Due to tidal and waves actions, the oil spillage affects the shorelines by adhering to the soil, making it difficult for immediate cleaning of the soil. As shoreline clean-up is the most costly component of a response operation, there is a need for effective oil remediation technologies. This paper provides a review on the remediation technologies for soil contaminated with various types of oil, including diesel, crude oil, petroleum, lubricating oil, bitumen and bunker oil. The methods discussed include solvent extraction, bioremediation, phytoremediation, chemical oxidation, electrokinetic remediation, thermal technologies, ultrasonication, flotation and integrated remediation technologies. Each of these technologies was discussed, and associated with their advantages, disadvantages, advancements and future work in detail. Nonetheless, it is important to note that no single remediation technology is considered the best solution for the remediation of oil contaminated soil. This review provides a comprehensive literature on the various remediation technologies studied in the removal of different oil types from soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Drinking Water Contamination Due To Lead-based Solder

    Science.gov (United States)

    Garcia, N.; Bartelt, E.; Cuff, K. E.

    2004-12-01

    The presence of lead in drinking water creates many health hazards. Exposure to lead-contaminated water can affect the brain, the central nervous system, blood cells, and kidneys, causing such problems as mental retardation, kidney disease, heart disease, stroke, and death. One way in which lead can contaminate our water supply is through the use of lead solder to join pipes. Lead solder was widely used in the past because of its ease of application as well as its low cost. Lead contamination in residential areas has previously been found to be a particularly serious problem in first-draw samples, of water that has sat stagnant in pipes overnight. To investigate the time-dependence of drinking water lead contamination, we analyzed samples taken hourly of water exposed to lead solder. While our preliminary data was insufficient to show more than a rough correlation between time of exposure and lead concentration over short periods (1-3 hours), we were able to confirm that overnight exposure of water to lead-based solder results in the presence high levels of lead. We also investigated other, external factors that previous research has indicated contribute to increased concentrations of lead. Our analysis of samples of lead-exposed water at various pH and temperatures suggests that these factors can be equally significant in terms of their contribution to elevated lead concentration levels. In particular, water that is slightly corrosive appears to severely impact the solubility of lead. As this type of water is common in much of the Northeast United States, the presence of lead-based solder in residential areas there is especially problematic. Although lead-based solder has been banned since the 1980s, it remains a serious concern, and a practical solution still requires further research.

  3. Ground-water contamination at Wurtsmith Air Force Base, Michigan

    Science.gov (United States)

    Stark, J.R.; Cummings, T.R.; Twenter, F.R.

    1983-01-01

    A sand and gravel aquifer of glacial origin underlies Wurtsmith Air Force Base in northeastern lower Michigan. The aquifer overlies a thick clay layer at an average depth of 65 feet. The water table is about 10 feet below land surface in the western part of the Base and about 25 feet below land surface in the eastern part. A ground-water divide cuts diagonally across the Base from northwest to southeast. South of the divide, ground water flows to the Au Sable River; north of the divide, it flows to Van Etten Creek and Van Etten Lake. Mathematical models were used to aid in calculating rates of groundwater flow. Rates range from about 0.8 feet per day in the eastern part of the Base to about 0.3 feet per day in the western part. Models also were used as an aid in making decisions regarding purging of contaminated water from the aquifer. In 1977, trichloroethylene was detected in the Air Force Base water-supply system. It had leaked from a buried storage tank near Building 43 in the southeastern part of the Base and moved northeastward under the influence of the natural ground-water gradient and the pumping of Base water-supply wells. In the most highly contaminated part of the plume, concentrations are greater than 1,000 micrograms per liter. Current purge pumping is removing some of the trichloroethylene, and seems to have arrested its eastward movement. Pumping of additional purge wells could increase the rate of removal. Trichloroethylene has also been detected in ground water in the vicinity of the Base alert apron, where a plume from an unknown source extends northeastward off Base. A smaller, less well-defined area of contamination also occurs just north of the larger plume. Trichloroethylene, identified near the waste-treatment plant, seepage lagoons, and the northern landfill area, is related to activities and operations in these areas. Dichloroethylene and trichloroethylene occur in significant quantities westward of Building 43, upgradient from the major

  4. The organic contamination level based on the total soil mass is not a proper index of the soil contamination intensity

    Science.gov (United States)

    Hung, H.-W.; Daniel, Sheng G.; Lin, T.-F.; Su, Y.; Chiou, C.T.

    2009-01-01

    Concentrations of organic contaminants in common productive soils based on the total soil mass give a misleading account of actual contamination effects. This is attributed to the fact that productive soils are essentially water-saturated, with the result that the soil uptake of organic compounds occurs principally by partition into the soil organic matter (SOM). This report illustrates that the soil contamination intensity of a compound is governed by the concentration in the SOM (Com) rather than by the concentration in whole soil (Cs). Supporting data consist of the measured levels and toxicities of many pesticides in soils of widely differing SOM contents and the related levels in in-situ crops that defy explanation by the Cs values. This SOM-based index is timely needed for evaluating the contamination effects of food crops grown in different soils and for establishing a dependable priority ranking for intended remediation of numerous contamination sites.

  5. Present and potential contamination of the river system at Mayak PA

    International Nuclear Information System (INIS)

    Amundsen, I.; Strand, P.; Malyshev, S.V.

    1999-01-01

    Studies of mobility of radionuclides in environmental samples at Mayak show that strontium-90 is the most mobile of the relevant radionuclides and hence can be transported by river water. Cesium-137, although less mobile, can also be transported over large distances. The main source of river contamination today is the remobilization of strontium-90 from the boggy area at the upper reaches of Techa River (Asanov Swamp). Regular Russian monitoring programmes show that levels of strontium-90 leaving the swamp are three times higher than levels entering the swamp. The net outflow from the Swamp is now estimated to 2-3% of the 37 TBq of strontium-90 located in the swamp, 1992 levels

  6. Development of plastic scintillator based food radioactivity contamination monitoring system

    International Nuclear Information System (INIS)

    Parihar, A.; Sahani, R.M.; Mahala, V.K.; Vaijapurkar, S.G.

    2016-01-01

    Radioactivity is naturally present in soil, water and food stuffs. Food can be contaminated after discharge of radioactivity into the environment from industries that concentrate natural radionuclide and from civil or military nuclear operations. The contamination can be in three ways; by direct deposition, through the food chain and induced radioactivity due to exposure of high neutron flux. The health effects on human depend on the type of radionuclide and the length of time people are exposed to it. The studies of fission product behaviour in the food chain have revealed radionuclide Strontium-90, Caesium 137 and Iodine-131 are of major concern. Plastic scintillator is already developed indigenously at Defence Laboratory, Jodhpur. Efforts has been made to develop a portable field instrument using plastic scintillator for assessment of beta ( 90 Sr) and gamma ( 137 Cs and 131 I) radioactivity in food

  7. Dacfood: a knowledge-based system for decision support in case of radiological contamination of foodstuffs

    International Nuclear Information System (INIS)

    Diaz, A.; Despres, A.; Soulatges, D.

    1991-01-01

    In case of radiological contamination of foodstuffs, the introduction of a countermeasure has to be justified by balancing its advantages and drawbacks, as recommended by ICRP. Also, to provide authorities with information about the decision context, it has been decided to develop a Decision Support System (DSS). A knowledge-based approach is used for the DSS. Indeed, it allows: . better modelling thanks to, for instance, object oriented programming and rules, . ability to introduce more knowledge thanks to an easier consistency and validity control of the knowledge base, . handling of uncertainties (incomplete, uncertain or evolving knowledge). The present state of the system is presented. DACFOOD is a decision aiding system for contamined foodstuffs, based on a knowledge-based approach. A demonstration model has been developed in a post-Chernobyl CEC research program. It evaluates the sanitary situation, the alternative actions through costs and sanitary effects, and gives information on the decisional background

  8. Using model-based screening to help discover unknown environmental contaminants.

    Science.gov (United States)

    McLachlan, Michael S; Kierkegaard, Amelie; Radke, Michael; Sobek, Anna; Malmvärn, Anna; Alsberg, Tomas; Arnot, Jon A; Brown, Trevor N; Wania, Frank; Breivik, Knut; Xu, Shihe

    2014-07-01

    Of the tens of thousands of chemicals in use, only a small fraction have been analyzed in environmental samples. To effectively identify environmental contaminants, methods to prioritize chemicals for analytical method development are required. We used a high-throughput model of chemical emissions, fate, and bioaccumulation to identify chemicals likely to have high concentrations in specific environmental media, and we prioritized these for target analysis. This model-based screening was applied to 215 organosilicon chemicals culled from industrial chemical production statistics. The model-based screening prioritized several recognized organosilicon contaminants and generated hypotheses leading to the selection of three chemicals that have not previously been identified as potential environmental contaminants for target analysis. Trace analytical methods were developed, and the chemicals were analyzed in air, sewage sludge, and sediment. All three substances were found to be environmental contaminants. Phenyl-tris(trimethylsiloxy)silane was present in all samples analyzed, with concentrations of ∼50 pg m(-3) in Stockholm air and ∼0.5 ng g(-1) dw in sediment from the Stockholm archipelago. Tris(trifluoropropyl)trimethyl-cyclotrisiloxane and tetrakis(trifluoropropyl)tetramethyl-cyclotetrasiloxane were found in sediments from Lake Mjøsa at ∼1 ng g(-1) dw. The discovery of three novel environmental contaminants shows that models can be useful for prioritizing chemicals for exploratory assessment.

  9. GPS-based handheld device for mapping contaminated areas

    International Nuclear Information System (INIS)

    Paridaens, J.

    2005-01-01

    Sometimes one is confronted with the challenge to map large areas with enhanced radioactivity. Examples are mine tailings or waste rock piles, deposits of the phosphate industry, flooding zones contaminated by effluents of plants processing ores containing enhanced natural radiation, nuclear accident sites etc. Car borne measuring equipment is not always an option, as the terrain might be rough and only accessible by foot. Airborne mapping with helicopters on the other hand is fast, but expensive, not readily available, shows difficulties with complex topography and lacks the necessary detail. The objective of this study was to create a portable and easily usable tool for the real time logging of radiation and location data, allowing mapping the radioactivity by simply walking over any kind of terrain with the portable equipment and post processing the data in the office. We also assessed the performance of the GPS based system on contaminated sites with areas varying from less than a hectare to several tens of hectares, with respect to speed, precision and ease of use. At sites of large scale mining and processing of uranium ore, tailings and waste rock piles are today the most visible relics of the uranium extractive industry. These mining relics are constantly subjected to weathering and leaching processes causing the dissemination of radioactive and toxic elements and sometimes requiring remedial operations. The in situ remediation of waste rock piles usually includes their revegetation for minimizing the water infiltration and for increasing surface soil stability. Thanks to its biomass density and longevity, the perennial vegetation plays an important role in stabilisation of the water cycling. The buffer role of forest vegetation can reduce water export from watersheds as well as erosion and hydrological losses of chemicals including radionuclides from contaminated sites. If long term reduction of contaminant dispersion at revegetated uranium mining sites is

  10. Development of an ecological risk assessment framework based on contaminant availability

    International Nuclear Information System (INIS)

    Menzie, C.; Linz, D.G.; Nakles, D.V.

    1995-01-01

    The Gas Research Institute (GRI) of Chicago, Illinois, recently completed the first phase of a research program to develop a methodology to determine environmentally acceptable endpoints or EAEs in soil. The results of this effort are being published by the American Academy of Environmental Engineers in a text, Environmentally Acceptable Endpoints in Soil: A Risk-Based Approach to Contaminated Site Management Based on Availability of Chemicals in Soil. This presentation will review the key technical findings of this first phase of research with an emphasis on the sequestration and bioavailability of organic compounds in soil and the effect of treatment on contaminant availability, mobility, and toxicity. A strawman protocol for the tiered evaluation of the ecological risk of a contaminated site based upon contaminant availability will also be examined. The use, refinement, and possible replacement of this protocol with alternative approaches is currently being discussed with a consortia of government, academia, and industrial representatives in the states of Washington and Texas and in the New England region. The results of these discussions will be presented and the critical technical and regulatory issues that have been identified by these consortia will be summarized. Possible alternative approaches to resolve the more significant issues will also be suggested

  11. The risk of contamination of food with toxic substances present in animal feed

    NARCIS (Netherlands)

    Kan, C.A.; Meijer, G.A.L.

    2007-01-01

    Toxic substances such as dioxins, mycotoxins, heavy metals, pesticides, veterinary drugs and polycyclic aromatic hydrocarbons are almost ubiquitous in the environment. Thus, they are also present in ingredients for animal feed. Adequate risk management depends on knowledge of absorption, metabolism,

  12. Presentations

    International Nuclear Information System (INIS)

    2007-01-01

    The presented materials consist of presentations of international workshop which held in Warsaw from 4 to 5 October 2007. Main subject of the meeting was progress in manufacturing as well as research program development for neutron detector which is planned to be placed at GANIL laboratory and will be used in nuclear spectroscopy research

  13. Presentation

    Directory of Open Access Journals (Sweden)

    Eduardo Vicente

    2013-06-01

    effectivities more than a number of fixed essential characteristics. Luiz Artur Ferrareto (UFRGS, undertaking a theoretical proposal for categorizing radio content in four different levels of planning (segment, form, programming and content itself tries to “compare and contrast the practices of Brazilian commercial broadcasting companies to those used on the radio in the United States, a reference market for our national entrepreneurs”. Madalena Oliveira (University of Minho focuses on the current stage of communication researches in Portugal reflecting on the challenges for studying a culture based on listening in times of looking. Marko Ala-Fossi, (University of Tampere beginning with the statement that “radio evolution greatly depends not only on the cultural context of a country but also on the whole social, political, economic development of societies” gives us a projection on radio development around the world for the next decades. Closing the dossier, Rafael Duarte Oliveira Venancio (UFU assuming radio as language by definition and not as a device understands it as a section and an operating model in such language as it intersects the world. Another six articles, not enrolled in the dossier, round the edition off. Fernando de Tacca debates the category of “photocine” recurring to three recent Spanish productions. Gustavo Souza investigates the possibility of identifying a point of view in documentary movies while establishing a debate that joins the materialities of image and sound with the subjectivity resulting from interpretation. Vinicius Bandeira develops on the special duplicity present in the movies between what is and what is not subsumed by the camera. Neide Jallageas proposes the study of visual communication design from the first modelings, attempting especially to the radical propositions from the early XXth century avant-garde movement. Gilson Schwartz debates on the impact from the distribution of videogames as hegemonic cultural practice in

  14. present

    African Journals Online (AJOL)

    as medium of instruction enhances concept formation, especially in science subjects as ... The study, on which this paper is based, was conducted to evaluate Malawi's ... corrected in the wake of information flowing from the evaluation phase (Kaplan .... concerning the background information and suggested activities (Thodi,.

  15. Community based bioremediation: grassroots responses to urban soil contamination

    Directory of Open Access Journals (Sweden)

    Scott Kellogg

    2016-12-01

    Full Text Available The past 150 years of industrial processes have left a legacy of toxicity in the soils of today’s urban environments. Exposure to soil based pollutants disproportionately affects low-income communities who are frequently located within formerly industrialized zones. Both gardeners, who come into direct contact with soil, as well as those who eat the products grown in the soil, are at risk to exposure from industrial contaminants. Options for low-income communities for remediating contaminated soils are limited, with most remediation work being carried out by costly engineering firms. Even more problematic is the overall lack of awareness and available information regarding safety and best practices with soils. In response to these challenges, a grassroots movement has emerged that seeks to empower urban residents with the tools and information necessary to address residual industrial toxicity in their ecosystems. Focusing on methods that are simple and affordable, this movement wishes to remove the barriers of cost and technical expertise that may be otherwise prohibitive. This paper will give an overview of this exemplar of generative justice, looking at case studies of organizations that have been successful in implementing these strategies.

  16. Presentations

    International Nuclear Information System (INIS)

    2007-01-01

    The PARIS meeting held in Cracow, Poland from 14 to 15 May 2007. The main subjects discussed during this meeting were the status of international project dedicated to gamma spectroscopy research. The scientific research program includes investigations of giant dipole resonance, probe of hot nuclei induced in heavy reactions, Jacobi shape transitions, isospin mixing and nuclear multifragmentation. The mentioned programme needs Rand D development such as new scintillations materials as lanthanum chlorides and bromides as well as new photo detection sensors as avalanche photodiodes - such subjects are also subjects of discussion. Additionally results of computerized simulations of scintillation detectors properties by means of GEANT- 4 code are presented

  17. Biofuel and other biomass based products from contaminated sites - Potentials and barriers from Swedish perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Andersson-Skoeld, Yvonne; Enell, Anja; Rihm, Thomas; Haglund, Kristina; Wik, Ola [Swedish Geotechnical Institute, Linkoeping (Sweden); Blom, Sonja; Angelbratt, Alexandra [FB Engineering AB, Goeteborg (Sweden); Bardos, Paul [r3 Environmental Technology Ltd, Reading (United Kingdom); Track, Thomas [DECHEMA e. V., Frankfurt am Main (Germany); Keuning, Sytze [Bioclear b.v., Groningen (Netherlands)

    2009-07-01

    In this report, results are presented based on interviews and literature surveys on the triggers and stoppers for non food crop on contaminated land in Sweden. The report also includes a first estimate of potential marginal land for biofuel production in Sweden. The report is a first step to explore the feasibility of a range of possible approaches to combine risk based land management (RBLM) with non-food crop land-uses and organic matter re-use as appropriate in a Swedish context. The focus of the report is on the treatment of contaminated land by phyto-remediation and on biofuel cultivation. In Sweden, like all other countries in Europe, areas of land have been degraded by past use. Such previously developed land includes areas affected by mining, fallout from industrial processes such as smelting, areas elevated with contaminated dredged sediments, former landfill sites and many other areas where the decline of industrial activity has left a legacy of degraded land and communities. The extent of contamination may not be sufficient to trigger remediation under current regulatory conditions, and there may be little economic incentive to regenerate the affected areas. An ideal solution would be a land management approach that is able to pay for itself. Biomass from coppice or other plantations has long been seen as a possible means of achieving this goal. Phyto remediation offers a low cost method for remediation of areas that are not candidates for conventional regeneration. The optimal conditions for phyto remediation are large land areas of low or mediate contamination. Phyto remediation is also suitable to prevent spreading of contaminants, for example in green areas such as in cities, as waste water buffer and small size remediation areas with diffuse spreading. Phyto remediation implies that plants, fungi or algae are used to remediate, control or increase the natural attenuation of contaminants. Depending on the contaminating species and the site conditions

  18. Biofuel and other biomass based products from contaminated sites - Potentials and barriers from Swedish perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Andersson-Skoeld, Yvonne; Enell, Anja; Rihm, Thomas; Haglund, Kristina; Wik, Ola (Swedish Geotechnical Institute, Linkoeping (Sweden)); Blom, Sonja; Angelbratt, Alexandra (FB Engineering AB, Goeteborg (Sweden)); Bardos, Paul (r3 Environmental Technology Ltd, Reading (United Kingdom)); Track, Thomas (DECHEMA e. V., Frankfurt am Main (Germany)); Keuning, Sytze (Bioclear b.v., Groningen (Netherlands))

    2009-07-01

    In this report, results are presented based on interviews and literature surveys on the triggers and stoppers for non food crop on contaminated land in Sweden. The report also includes a first estimate of potential marginal land for biofuel production in Sweden. The report is a first step to explore the feasibility of a range of possible approaches to combine risk based land management (RBLM) with non-food crop land-uses and organic matter re-use as appropriate in a Swedish context. The focus of the report is on the treatment of contaminated land by phyto-remediation and on biofuel cultivation. In Sweden, like all other countries in Europe, areas of land have been degraded by past use. Such previously developed land includes areas affected by mining, fallout from industrial processes such as smelting, areas elevated with contaminated dredged sediments, former landfill sites and many other areas where the decline of industrial activity has left a legacy of degraded land and communities. The extent of contamination may not be sufficient to trigger remediation under current regulatory conditions, and there may be little economic incentive to regenerate the affected areas. An ideal solution would be a land management approach that is able to pay for itself. Biomass from coppice or other plantations has long been seen as a possible means of achieving this goal. Phyto remediation offers a low cost method for remediation of areas that are not candidates for conventional regeneration. The optimal conditions for phyto remediation are large land areas of low or mediate contamination. Phyto remediation is also suitable to prevent spreading of contaminants, for example in green areas such as in cities, as waste water buffer and small size remediation areas with diffuse spreading. Phyto remediation implies that plants, fungi or algae are used to remediate, control or increase the natural attenuation of contaminants. Depending on the contaminating species and the site conditions

  19. Fluoride contamination sensor based on optical fiber grating technology

    Science.gov (United States)

    Jadhav, Mangesh S.; Laxmeshwar, Lata S.; Akki, Jyoti F.; Raikar, P. U.; Kumar, Jitendra; Prakash, Om; Raikar, U. S.

    2017-11-01

    A number of distinct advantages of the optical fiber technology in the field of sensors and communications which leads to enormous applications. Fiber Bragg grating (FBG) developed from the fabrication of photosensitive fiber through phase mask technique is used in the present report. The designed fiber sensor used for the detection and determination of contaminants in drinking water at ppm & ppb level and it is considered as a special type of concentration sensor. The test samples of drinking water have been collected from different regions. In this paper we have calibrated the FBG sensor to detect Flouride concentration in drinking water in the range of 0.05-8 ppm. According to WHO, the normal range of fluoride content in drinking water is about 0.7 ppm to 1.5 ppm. The results for resultant spectral shifts for test samples are closely agree with standard values.

  20. Laser-based characterization and decontamination of contaminated facilities

    International Nuclear Information System (INIS)

    Leong, K.H.; Hunter, B.V.; Grace, J.E.; Pellin, M.J.; Leidich, H.F.; Kugler, T.R.

    1996-01-01

    This study examines the application of laser ablation to the characterization and decontamination of painted and unpainted concrete and metal surfaces that are typical of many facilities within the US Department of Energy complex. The utility of this promising technology is reviewed and the essential requirements for efficient ablation extracted. Recent data obtained on the ablation of painted steel surfaces and concrete are presented. The affects of beam irradiance, ablation speed and efficiency, and characteristics of the aerosol effluent are discussed. Characterization of the ablated components of the surface offers the ability of concurrent determination of the level of contamination. This concept can be applied online where the ablation endpoint can be determined. A conceptual system for the characterization and decontamination of surfaces is proposed

  1. International workshop on scientific bases for decision making after a radioactive contamination of an urban environment. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    This workshop aims to discuss the most important aspects of scientific bases for decision making after a radioactive contamination in urban environment and to identify some scientific, social and economic open questions. Papers explaining in more details the principles of intervention, computational capabilities and measurements after a contamination of urban areas are presented. A review on practical experiences from Chernobyl and Goiania accidents is also included.

  2. International workshop on scientific bases for decision making after a radioactive contamination of an urban environment. Book of abstracts

    International Nuclear Information System (INIS)

    1994-01-01

    This workshop aims to discuss the most important aspects of scientific bases for decision making after a radioactive contamination in urban environment and to identify some scientific, social and economic open questions. Papers explaining in more details the principles of intervention, computational capabilities and measurements after a contamination of urban areas are presented. A review on practical experiences from Chernobyl and Goiania accidents is also included

  3. Quantification of Human and Animal Viruses to Differentiate the Origin of the Fecal Contamination Present in Environmental Samples

    Directory of Open Access Journals (Sweden)

    Sílvia Bofill-Mas

    2013-01-01

    Full Text Available Many different viruses are excreted by humans and animals and are frequently detected in fecal contaminated waters causing public health concerns. Classical bacterial indicator such as E. coli and enterococci could fail to predict the risk for waterborne pathogens such as viruses. Moreover, the presence and levels of bacterial indicators do not always correlate with the presence and concentration of viruses, especially when these indicators are present in low concentrations. Our research group has proposed new viral indicators and methodologies for determining the presence of fecal pollution in environmental samples as well as for tracing the origin of this fecal contamination (microbial source tracking. In this paper, we examine to what extent have these indicators been applied by the scientific community. Recently, quantitative assays for quantification of poultry and ovine viruses have also been described. Overall, quantification by qPCR of human adenoviruses and human polyomavirus JC, porcine adenoviruses, bovine polyomaviruses, chicken/turkey parvoviruses, and ovine polyomaviruses is suggested as a toolbox for the identification of human, porcine, bovine, poultry, and ovine fecal pollution in environmental samples.

  4. Contamination control plan for prelaunch operations

    Science.gov (United States)

    Austin, J. D.

    1983-01-01

    A unified, systematic plan is presented for contamination control for space flight systems. Allowable contaminant quantities, or contamination budgets, are determined based on system performance margins and system-level allowable degradations. These contamination budgets are compared to contamination rates in ground environments to establish the controls required in each ground environment. The use of feedback from contamination monitoring and some contamination control procedures are discussed.

  5. Risk-Based Approach for Thermal Treatment of Soils Contaminated with Heavy Metals

    Directory of Open Access Journals (Sweden)

    Cocârţă D. M.

    2013-04-01

    Full Text Available In the actual context of limited soil resources and the significant degree of environmental pollution, public administrations and authorities are interested in restoring contaminated sites paying attention to the impact of these soils on human health. This paper aims to present the efficiency of the the incineration as a method for treatment of the contaminated soils t based on human health risk assessment. Through various experimentations, the following metals have been studied: Zn, Cu, Fe, Mn, Ni, Pb, Cr, Co, Cd, Hg, As and Be. The most important and interesting results concerning both thermal treatment removal efficiency and associated human health risk assessments were achieved concerning Cd, Pb and Ni contaminants. The behavior of Cadmium (Cd, Lead (Pb and Nickel (Ni concentrations from heavy metals incineration soil has been analyzed for three incineration temperatures (600°C, 800°C and 1000°C and two resident times of soil within the incineration reactor (30 min. and 60 min.. In this case, the level of contaminants in the treated soil can be reduced but not enough to ensure an acceptable risk for human health.

  6. Pavlovian disgust conditioning as a model for contamination-based OCD: Evidence from an analogue study.

    Science.gov (United States)

    Armstrong, Thomas; Olatunji, Bunmi O

    2017-06-01

    Pavlovian fear conditioning provides a model for anxiety-related disorders, including obsessive-compulsive disorder (OCD). However, disgust is the predominant emotional response to contamination, which is a common theme in OCD. The present study sought to identify disgust conditioning abnormalities that may underlie excessive contamination concerns relevant to OCD. Individuals high and low in contamination concern (HCC, n = 32; LCC, n = 30) completed an associative learning task in which one neutral face (conditioned stimulus; CS+) was followed by a disgusting image (unconditioned stimulus; US) and another neutral face (CS-) was unreinforced. Following this acquisition procedure, there was an extinction procedure in which both CSs were presented unreinforced. The groups did not show significant differences in discriminant responding to the CSs following acquisition. However, following extinction, the HCC group reported less reduction in their expectancy of the US following the CS+, and also reported greater disgust to the CS+, compared to the LCC group. Increased disgust to the CS+ following both acquisition and extinction was correlated with increased symptoms of contamination-based OCD and increased disgust sensitivity. Additionally, disgust sensitivity mediated group differences in disgust responding to the CS+ at acquisition and extinction. Also, failure to adjust US expectancy in response to extinction partially mediated group differences in disgust to the CS+ following extinction. Together, these findings suggest that excessive contamination concerns observed in OCD may be related to difficulty inhibiting acquired disgust, possibly due to elevated disgust sensitivity that characterizes the disorder. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. N.V. Timofeev-Resovsky's ideas in present studies of radioactive contamination zones of the Urals

    International Nuclear Information System (INIS)

    Molchanova, I.V.; Pozolotina, V.N.; Karavaeva, E.N.; Antonova, E.V.; Mikhaylovskaya, L.N.

    2008-01-01

    The theory of living substance and the Earth biosphere by the brilliant Russian scientist V.I. Vernadsky has produced a great world view effect. Basing on this theory another prominent Russian researcher N.V. Timofeev-Resovsky came up to formation of a new scientific discipline - radioecology. He identified two basic areas of research in radioecology (radiation biocenology): 1) studies of the radionuclide fate in natural ecosystems and 2) assessment of biological effects of ionizing radiation on living organisms, population, ecosystems. In our research activities conducted in the East Uralian Radioactive Trail (EURT) zone resulted from an accident at the Mayak concern in 1957, we attempted to advance some ideas of Timofeev-Resovsky (1957). The objectives of research were to assess recent levels and distribution of radio-nuclides between ecosystem components along the contamination gradient and 2) to study effects of low levels of chronic radiation exposure on populations of herbaceous plants (author)(tk)

  8. Semi-automated relative quantification of cell culture contamination with mycoplasma by Photoshop-based image analysis on immunofluorescence preparations.

    Science.gov (United States)

    Kumar, Ashok; Yerneni, Lakshmana K

    2009-01-01

    Mycoplasma contamination in cell culture is a serious setback for the cell-culturist. The experiments undertaken using contaminated cell cultures are known to yield unreliable or false results due to various morphological, biochemical and genetic effects. Earlier surveys revealed incidences of mycoplasma contamination in cell cultures to range from 15 to 80%. Out of a vast array of methods for detecting mycoplasma in cell culture, the cytological methods directly demonstrate the contaminating organism present in association with the cultured cells. In this investigation, we report the adoption of a cytological immunofluorescence assay (IFA), in an attempt to obtain a semi-automated relative quantification of contamination by employing the user-friendly Photoshop-based image analysis. The study performed on 77 cell cultures randomly collected from various laboratories revealed mycoplasma contamination in 18 cell cultures simultaneously by IFA and Hoechst DNA fluorochrome staining methods. It was observed that the Photoshop-based image analysis on IFA stained slides was very valuable as a sensitive tool in providing quantitative assessment on the extent of contamination both per se and in comparison to cellularity of cell cultures. The technique could be useful in estimating the efficacy of anti-mycoplasma agents during decontaminating measures.

  9. RBCA-based approaches to ecological risk assessment for TPH-contaminated areas

    International Nuclear Information System (INIS)

    Hummell, R.; Vedagiri, U.

    1995-01-01

    The RBCA guidelines proposed by ASTM form an evaluation and decision-making framework for sites potentially contaminated by petroleum releases. They present a three-tiered approach of decreasing conservatism and increasing site-specificity that primarily evaluates risks to human health. While RBCA includes consideration of environmental impacts, there are no specific recommendations on how this is to be achieved. A RBCA-based ecological risk assessment approach was developed for TPH-contaminated areas in Alaska. The approach presents a habitat-based selection process for surrogate chemicals and indicator chemicals of ecological relevance, evaluation of ecotoxicity, derivation of matrix-specific Tier 1 RBSLs (including soils) and determination of Tier 2 and 3 SSTLS. Chemicals are considered by class, aquatic (freshwater and saltwater) and terrestrial habitats are evaluated independently, and chemical concentrations are screened in all media of concern (air, soil, water, sediment). Data needs and decision points specific to ecological receptors are identified for each tier of the approach. Other aspects of the approach include consideration of contaminant migration pathways and habitats that are typical of Arctic conditions. Areas where ecological and human risk concerns may overlap are identified

  10. Bayesian based design of real-time sensor systems for high-risk indoor contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Sreedharan, Priya [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    -system performance and offset the need for more contaminant sensors. Physics- and algorithm-based frameworks are presented for selecting and fusing information from noncontaminant sensors. The frameworks are demonstrated with door-position sensors, which are found to be more useful in natural airflow conditions, but which cannot compensate for poor placement of contaminant sensors. The concepts and empirical findings have the potential to help in the design of sensor systems for more complex building systems. The research has broader relevance to additional environmental monitoring problems, fault detection and diagnostics, and system design.

  11. (CultiAF) Reducing maize-based aflatoxin contamination

    International Development Research Centre (IDRC) Digital Library (Canada)

    In Zimbabwe, testing of harvested maize has revealed high levels of contamination by aflatoxins, ... and other private sector partners will increase the availability of improved grain storage containers. Researchers will work with the Ministry of ...

  12. Reducing maize-based aflatoxin contamination and exposure

    International Development Research Centre (IDRC) Digital Library (Canada)

    super bags' in which to store their grain. The control households will continue using traditional storage techniques. Researchers will assess the extent of aflatoxin contamination in grain stored by both groups and levels of exposure in mothers ...

  13. Transuranic contaminated waste form characterization and data base

    International Nuclear Information System (INIS)

    Kniazewycz, B.G.; McArthur, W.C.

    1980-07-01

    This volume contains 5 appendices. Title listing are: technologies for recovery of transuranics; nondestructive assay of TRU contaminated wastes; miscellaneous waste characteristics; acceptance criteria for TRU waste; and TRU waste treatment technologies

  14. Insulator Contamination Forecasting Based on Fractal Analysis of Leakage Current

    Directory of Open Access Journals (Sweden)

    Bing Luo

    2012-07-01

    Full Text Available In this paper, an artificial pollution test is carried out to study the leakage current of porcelain insulators. Fractal theory is adopted to extract the characteristics hidden in leakage current waveforms. Fractal dimensions of the leakage current for the security, forecast and danger zones are analyzed under four types of degrees of contamination. The mean value and the standard deviation of the fractal dimension in the forecast zone are calculated to characterize the differences. The analysis reveals large differences in the fractal dimension of leakage current under different contamination discharge stages and degrees. The experimental and calculation results suggest that the fractal dimension of a leakage current waveform can be used as a new indicator of the discharge process and contamination degree of insulators. The results provide new methods and valid indicators for forecasting contamination flashovers.

  15. Chordoma of skull base presenting as nasopharyngeal mass

    Directory of Open Access Journals (Sweden)

    Sant Prakash Kataria

    2013-01-01

    Full Text Available While the nasopharynx is most commonly regarded by the otolaryngologist as a primary site of neoplastic involvement, it is also an avenue of spread of base-of-the-skull tumors presenting as bulging nasopharyngeal masses. Chordoma is a relatively rare tumor of the skull base and sacrum thought to originate from embryonic remnants of the notochord. Chordomas arising from the skull base/clivus are typically locally aggressive with lytic bone destruction. The optimal treatment may be photon/proton radiotherapy alone or combined with a gross total resection, when feasible. We report a case of intracranial chordoma presenting as nasopharyngeal mass.

  16. Incorporating linguistic, probabilistic, and possibilistic information in a risk-based approach for ranking contaminated sites.

    Science.gov (United States)

    Zhang, Kejiang; Achari, Gopal; Pei, Yuansheng

    2010-10-01

    Different types of uncertain information-linguistic, probabilistic, and possibilistic-exist in site characterization. Their representation and propagation significantly influence the management of contaminated sites. In the absence of a framework with which to properly represent and integrate these quantitative and qualitative inputs together, decision makers cannot fully take advantage of the available and necessary information to identify all the plausible alternatives. A systematic methodology was developed in the present work to incorporate linguistic, probabilistic, and possibilistic information into the Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE), a subgroup of Multi-Criteria Decision Analysis (MCDA) methods for ranking contaminated sites. The identification of criteria based on the paradigm of comparative risk assessment provides a rationale for risk-based prioritization. Uncertain linguistic, probabilistic, and possibilistic information identified in characterizing contaminated sites can be properly represented as numerical values, intervals, probability distributions, and fuzzy sets or possibility distributions, and linguistic variables according to their nature. These different kinds of representation are first transformed into a 2-tuple linguistic representation domain. The propagation of hybrid uncertainties is then carried out in the same domain. This methodology can use the original site information directly as much as possible. The case study shows that this systematic methodology provides more reasonable results. © 2010 SETAC.

  17. A consideration on internal dose evaluation and intervention based on a surface contamination concept

    International Nuclear Information System (INIS)

    Yasuda, H.

    1997-01-01

    Long-term radiation doses received by the inhabitants after the Chernobyl accident have been evaluated according to the surface contamination levels on the ground surface. The health effects have also been discussed by comparison between the surface-contaminated area and the uncontaminated control area. Selected protective measures were carried out in accordance with the contamination level of surface soil. These have been based on the 'surface contamination concept' which assumes that the radiation risk to inhabitants is proportional to the level of ground-surface contamination. The observations collected in regions around Chernobyl, however, show that the internal radiation doses to the inhabitants poorly correlate with the surface contamination level. This fact poses a question on the suitability of dose evaluations and interventions based on this concept

  18. Persistence of Trace Organic Contaminants from a Commercial Biosolids-Based Fertilizer in Aerobic Soils

    OpenAIRE

    Banet, Travis A; Kim, Jihyun R; Mashtare, Michael L

    2016-01-01

    Municipal biosolids are recycled as agricultural fertilizers. Recent studies have raised concerns due to the presence of emerging contaminants in municipal biosolids. Previous research suggests that these contaminants have the potential to reside in biosolids-based fertilizers that are commercially distributed. Use of these products in urban/suburban areas may provide a pathway for these contaminants to enter ecosystems and impact human and environmental health. Soils from Purdue University’s...

  19. Managing long-term polycyclic aromatic hydrocarbon contaminated soils: a risk-based approach.

    Science.gov (United States)

    Duan, Luchun; Naidu, Ravi; Thavamani, Palanisami; Meaklim, Jean; Megharaj, Mallavarapu

    2015-06-01

    Polycyclic aromatic hydrocarbons (PAHs) are a family of contaminants that consist of two or more aromatic rings fused together. Soils contaminated with PAHs pose significant risk to human and ecological health. Over the last 50 years, significant research has been directed towards the cleanup of PAH-contaminated soils to background level. However, this achieved only limited success especially with high molecular weight compounds. Notably, during the last 5-10 years, the approach to remediate PAH-contaminated soils has changed considerably. A risk-based prioritization of remediation interventions has become a valuable step in the management of contaminated sites. The hydrophobicity of PAHs underlines that their phase distribution in soil is strongly influenced by factors such as soil properties and ageing of PAHs within the soil. A risk-based approach recognizes that exposure and environmental effects of PAHs are not directly related to the commonly measured total chemical concentration. Thus, a bioavailability-based assessment using a combination of chemical analysis with toxicological assays and nonexhaustive extraction technique would serve as a valuable tool in risk-based approach for remediation of PAH-contaminated soils. In this paper, the fate and availability of PAHs in contaminated soils and their relevance to risk-based management of long-term contaminated soils are reviewed. This review may serve as guidance for the use of site-specific risk-based management methods.

  20. Present situation of radioactive contamination in and around the former Soviet Union's Semipalatinsk nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, M. [Kanazawa Univ., Low Level Radioactivity Laboratory, Ishikawa (Japan); Hoshi, M.; Takada, J. [Hiroshima Univ., Research Institute for Radiation Biology and Medicine, Hiroshima (Japan); Tsukatani, T. [Kyoto Univ., Kyoto Institute of Economic Research, Kyoto (Japan); Oikawa, S. [Japan Chemical Analytical Center, Inage, Chiba (Japan); Yoshikawa, I.; Takatsuji, T. [Nagasaki Univ., Faculty of Environmental Studies, Nagasaki (Japan); Sekerbaev, A. Kh.; Gusev, B.I. [Kazakh Scientific Research Institute for Radiation Medicine and Ecology, Semipalatinsk (Kazakhstan)

    2001-03-01

    Field missions were sent to the Semipalatinsk regions to investigate the present radioecological situation as a result of the radioactive fallout from nuclear test explosions carried out at the former Soviet Union's Semipalatinsk nuclear test site (SNTS). For this purpose, surface and core soil samples were collected at more than 60 sites, including several settlements such as Dolon, Chagan and Sarzhal, within and outside the SNTS territory. The radioactivities of long-lived radionuclides, {sup 137}Cs, {sup 238}Pu and {sup 239,240}Pu, and the atomic ratio of {sup 240}Pu/{sup 239}Pu were determined in combination with non-destructive g-ray spectrometric method and radiochemical separation followed by a-particle spectrometric and/or ICP-MS methods. The results showed a distinction of {sup 137}Cs and {sup 239,240}Pu inventories in soil depending on a sampling sites. Although {sup 137}Cs was within typical environmental levels except for the area near the first nuclear test site and Balapan, {sup 239,240}Pu was at elevated levels in all areas we visited. This high Pu contamination was recognized to be due to the weapons-grade Pu from the SNTS by the measurement of {sup 240}Pu/{sup 239P}u atomic ratio in soil samples. (author)

  1. Development of Presentation Model with Cloud Based Infrastructure

    Directory of Open Access Journals (Sweden)

    Magdalena Widiantari Maria

    2018-01-01

    Full Text Available Computer mediated communication are the communication activities using technology which have rapidly in progress. Communication interactive activities nowadays has no longer only involving person to person but mediated by technology, and have been done in many fields including in education and teaching activity. In this study, presentation media based on cloud's infrastructure designed to replace face to face or in class lectures. In addition, the presentation will allow media data storage indefinitely, and accessible wherever and anytime. This is in line with the concept of student center learning where students were encouraged to more active in the lecture activities. The purpose of this research is making or designing a presentation model based on cloud‘s infrastructure. This research is using research and development method which is consists of four stages, where the first phase is composing the concept of media presentation design. The second phase are choosing the subject that will be designed as the subject of presentation. The third stage is designing presentation model. And the fourth phase is collecting materials of the subject that will be presented by each lecturer.

  2. Emerging contaminants in the environment: Risk-based analysis for better management.

    Science.gov (United States)

    Naidu, Ravi; Arias Espana, Victor Andres; Liu, Yanju; Jit, Joytishna

    2016-07-01

    Emerging contaminants (ECs) are chemicals of a synthetic origin or deriving from a natural source that has recently been discovered and for which environmental or public health risks are yet to be established. This is due to limited available information on their interaction and toxicological impacts on receptors. Several types of ECs exist such as antibiotics, pesticides, pharmaceuticals, personal care products, effluents, certain naturally occurring contaminants and more recently nanomaterials. ECs may derive from a known source, for example released directly to the aquatic environment from direct discharges such as those from wastewater treatment plants. Although in most instances the direct source cannot be identified, ECs have been detected in virtually every country's natural environment and as a consequence they represent a global problem. There is very limited information on the fate and transport of ECs in the environment and their toxicological impact. This lack of information can be attributed to limited financial resources and the lack of analytical techniques for detecting their effects on ecosystems and human health on their own or as mixture. We do not know how ECs interact with each other or various contaminants. This paper presents an overview of existing knowledge on ECs, their fate and transport and a risk-based analysis for ECs management and complementary strategies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Removal of lead and fluoride from contaminated water using exhausted coffee grounds based bio-sorbent.

    Science.gov (United States)

    Naga Babu, A; Reddy, D Srinivasa; Kumar, G Suresh; Ravindhranath, K; Krishna Mohan, G V

    2018-07-15

    Water pollution by industrial and anthropogenic actives has become a serious threat to the environment. World Health Organization (WHO) has identified that lead and fluoride amid the environmental pollutants are most poisonous water contaminants with devastating impact on the human race. The present work proposes a study on economical bio-adsorbent based technique using exhausted coffee grounds in the removal of lead and fluoride contaminants from water. The exhausted coffee grounds gathered from industrial wastes have been acid-activated and examined for their adsorption capacity. The surface morphology and elemental characterization of pre-and-post adsorption operations by FESEM, EDX and FTIR spectral analysis confirmed the potential of the exhausted coffee ground as successful bio-sorbent. However, thermodynamic analysis confirmed the adsorption to be spontaneous physisorption with Langmuir mode of homogenous monolayer deposition. The kinetics of adsorption is well defined by pseudo second order model for both lead and fluoride. A significant quantity of lead and fluoride is removed from the synthetic contaminated water by the proposed bio-sorbent with the respective sorption capabilities of 61.6 mg/g and 9.05 mg/g. However, the developed bio-sorbent is also recyclable and is capable of removing the lead and fluoride from the domestic and industrial waste-water sources with an overall removal efficiency of about 90%. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Raman spectroscopy-based detection of chemical contaminants in food powders

    Science.gov (United States)

    Raman spectroscopy technique has proven to be a reliable method for qualitative detection of chemical contaminants in food ingredients and products. For quantitative imaging-based detection, each contaminant particle in a food sample must be detected and it is important to determine the necessary sp...

  5. Towards bioavailability-based soil criteria: Past, present and future perspectives

    Science.gov (United States)

    Bioavailability has been used as a key indicator in chemical risk assessment, yet it is a poorly quantified risk factor. Worldwide, the framework used to assess potentially contaminated sites is similar and the decisions are based on threshold contaminant concentration. The uncertainty in the defin...

  6. Modelling and simulation-based acquisition decision support: present & future

    CSIR Research Space (South Africa)

    Naidoo, S

    2009-10-01

    Full Text Available stream_source_info Naidoo1_2009.pdf.txt stream_content_type text/plain stream_size 24551 Content-Encoding UTF-8 stream_name Naidoo1_2009.pdf.txt Content-Type text/plain; charset=UTF-8 1 Modelling & Simulation...-Based Acquisition Decision Support: Present & Future Shahen Naidoo Abstract The Ground Based Air Defence System (GBADS) Programme, of the South African Army has been applying modelling and simulation (M&S) to provide acquisition decision and doctrine...

  7. Voice and gesture-based 3D multimedia presentation tool

    Science.gov (United States)

    Fukutake, Hiromichi; Akazawa, Yoshiaki; Okada, Yoshihiro

    2007-09-01

    This paper proposes a 3D multimedia presentation tool that allows the user to manipulate intuitively only through the voice input and the gesture input without using a standard keyboard or a mouse device. The authors developed this system as a presentation tool to be used in a presentation room equipped a large screen like an exhibition room in a museum because, in such a presentation environment, it is better to use voice commands and the gesture pointing input rather than using a keyboard or a mouse device. This system was developed using IntelligentBox, which is a component-based 3D graphics software development system. IntelligentBox has already provided various types of 3D visible, reactive functional components called boxes, e.g., a voice input component and various multimedia handling components. IntelligentBox also provides a dynamic data linkage mechanism called slot-connection that allows the user to develop 3D graphics applications by combining already existing boxes through direct manipulations on a computer screen. Using IntelligentBox, the 3D multimedia presentation tool proposed in this paper was also developed as combined components only through direct manipulations on a computer screen. The authors have already proposed a 3D multimedia presentation tool using a stage metaphor and its voice input interface. This time, we extended the system to make it accept the user gesture input besides voice commands. This paper explains details of the proposed 3D multimedia presentation tool and especially describes its component-based voice and gesture input interfaces.

  8. Challenge Based Innovation @ mediterranean - final presentations & prototype expo

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Challenge Based Innovation @ mediterranean - Final presentations & prototype expo Challenge Based Innovation (CBI) is a six-month project course, where multidisciplinary student teams and their instructors collaborate with researchers at CERN to discover novel solutions for the future of humankind. The projects are an elaborate mixture, where societal, human-driven needs meet research at CERN. More info about CBI from the course website, cbi-course.com The Gala on 10.12. will introduce the proof-of concept prototypes the four student teams have developed to answer a wide range of societal challenges, inspired by people and research at CERN.   Dress code: a suit / dress  is not required - come as you are! Register for live attendance & CERN access for external visitors. Webcast and/or recorded presentations will be available here in the Indico page for anyone interested.  The space is limited to 50 participants, so act quickly! &...

  9. Challenge Based Innovation @ mediterranean - final presentations & prototype expo

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    Challenge Based Innovation @ mediterranean - Final presentations & prototype expo Note - presentation location has been changed to the council chamber (503-1-001) due to the large amount of signups. External participants are guided from the main reception (building 33), more information over email on Wednesday. Prototype presentations are still at IdeaSquare (3179) 18.00 - 19.30, guided walking from the presentations.  Challenge Based Innovation (CBI) is a four month project course, where multidisciplinary student teams and their instructors collaborate with researchers at CERN to discover novel solutions for the future of humankind. The projects are an elaborate mixture, where societal, human-driven needs meet research at CERN. More info about CBI from the course website, cbi-course.com The Gala on 1.12. will introduce the proof-of concept prototypes the five student teams have developed to answer a wide range of societal challenges, inspired by people and r...

  10. Optical reading of contaminants in aqueous media based on gold nanoparticles.

    Science.gov (United States)

    Du, Jianjun; Zhu, Bowen; Peng, Xiaojun; Chen, Xiaodong

    2014-09-10

    With increasing trends of global population growth, urbanization, pollution over-exploitation, and climate change, the safe water supply has become a global issue and is threatening our society in terms of sustainable development. Therefore, there is a growing need for a water-monitoring platform with the capability of rapidness, specificity, low-cost, and robustness. This review summarizes the recent developments in the design and application of gold nanoparticles (AuNPs) based optical assays to detect contaminants in aqueous media with a high performance. First, a brief discussion on the correlation between the optical reading strategy and the optical properties of AuNPs is presented. Then, we summarize the principle behind AuNP-based optical assays to detect different contaminants, such as toxic metal ion, anion, and pesticides, according to different optical reading strategies: colorimetry, scattering, and fluorescence. Finally, the comparison of these assays and the outlook of AuNP-based optical detection are discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Detection of water-quality contamination events based on multi-sensor fusion using an extented Dempster–Shafer method

    International Nuclear Information System (INIS)

    Hou, Dibo; He, Huimei; Huang, Pingjie; Zhang, Guangxin; Loaiciga, Hugo

    2013-01-01

    This study presents a method for detecting contamination events of sources of drinking water based on the Dempster–Shafer (D-S) evidence theory. The detection method has the purpose of protecting water supply systems against accidental and intentional contamination events. This purpose is achieved by first predicting future water-quality parameters using an autoregressive (AR) model. The AR model predicts future water-quality parameters using recent measurements of these parameters made with automated (on-line) water-quality sensors. Next, a probabilistic method assigns probabilities to the time series of residuals formed by comparing predicted water-quality parameters with threshold values. Finally, the D-S fusion method searches for anomalous probabilities of the residuals and uses the result of that search to determine whether the current water quality is normal (that is, free of pollution) or contaminated. The D-S fusion method is extended and improved in this paper by weighted averaging of water-contamination evidence and by the analysis of the persistence of anomalous probabilities of water-quality parameters. The extended D-S fusion method makes determinations that have a high probability of being correct concerning whether or not a source of drinking water has been contaminated. This paper's method for detecting water-contamination events was tested with water-quality time series from automated (on-line) water quality sensors. In addition, a small-scale, experimental, water-pipe network was tested to detect water-contamination events. The two tests demonstrated that the extended D-S fusion method achieves a low false alarm rate and high probabilities of detecting water contamination events. (paper)

  12. Health Risk-Based Assessment and Management of Heavy Metals-Contaminated Soil Sites in Taiwan

    Directory of Open Access Journals (Sweden)

    Zueng-Sang Chen

    2010-10-01

    Full Text Available Risk-based assessment is a way to evaluate the potential hazards of contaminated sites and is based on considering linkages between pollution sources, pathways, and receptors. These linkages can be broken by source reduction, pathway management, and modifying exposure of the receptors. In Taiwan, the Soil and Groundwater Pollution Remediation Act (SGWPR Act uses one target regulation to evaluate the contamination status of soil and groundwater pollution. More than 600 sites contaminated with heavy metals (HMs have been remediated and the costs of this process are always high. Besides using soil remediation techniques to remove contaminants from these sites, the selection of possible remediation methods to obtain rapid risk reduction is permissible and of increasing interest. This paper discusses previous soil remediation techniques applied to different sites in Taiwan and also clarified the differences of risk assessment before and after soil remediation obtained by applying different risk assessment models. This paper also includes many case studies on: (1 food safety risk assessment for brown rice growing in a HMs-contaminated site; (2 a tiered approach to health risk assessment for a contaminated site; (3 risk assessment for phytoremediation techniques applied in HMs-contaminated sites; and (4 soil remediation cost analysis for contaminated sites in Taiwan.

  13. Health Risk-Based Assessment and Management of Heavy Metals-Contaminated Soil Sites in Taiwan

    Science.gov (United States)

    Lai, Hung-Yu; Hseu, Zeng-Yei; Chen, Ting-Chien; Chen, Bo-Ching; Guo, Horng-Yuh; Chen, Zueng-Sang

    2010-01-01

    Risk-based assessment is a way to evaluate the potential hazards of contaminated sites and is based on considering linkages between pollution sources, pathways, and receptors. These linkages can be broken by source reduction, pathway management, and modifying exposure of the receptors. In Taiwan, the Soil and Groundwater Pollution Remediation Act (SGWPR Act) uses one target regulation to evaluate the contamination status of soil and groundwater pollution. More than 600 sites contaminated with heavy metals (HMs) have been remediated and the costs of this process are always high. Besides using soil remediation techniques to remove contaminants from these sites, the selection of possible remediation methods to obtain rapid risk reduction is permissible and of increasing interest. This paper discusses previous soil remediation techniques applied to different sites in Taiwan and also clarified the differences of risk assessment before and after soil remediation obtained by applying different risk assessment models. This paper also includes many case studies on: (1) food safety risk assessment for brown rice growing in a HMs-contaminated site; (2) a tiered approach to health risk assessment for a contaminated site; (3) risk assessment for phytoremediation techniques applied in HMs-contaminated sites; and (4) soil remediation cost analysis for contaminated sites in Taiwan. PMID:21139851

  14. Transuranic contaminated waste form characterization and data base

    International Nuclear Information System (INIS)

    McArthur, W.C.; Kniazewycz, B.G.

    1980-07-01

    This report outlines the sources, quantities, characteristics and treatment of transuranic wastes in the United States. This document serves as part of the data base necessary to complete preparation and initiate implementation of transuranic wastes, waste forms, waste container and packaging standards and criteria suitable for inclusion in the present NRC waste management program. No attempt is made to evaluate or analyze the suitability of one technology over another. Indeed, by the nature of this report, there is little critical evaluation or analysis of technologies because such analysis is only appropriate when evaluating a particular application or transuranic waste streams. Due to fiscal restriction, the data base is developed from a myriad of technical sources and does not necessarily contain operating experience and the current status of all technologies. Such an effort was beyond the scope of this report

  15. Transuranic contaminated waste form characterization and data base

    Energy Technology Data Exchange (ETDEWEB)

    McArthur, W.C.; Kniazewycz, B.G.

    1980-07-01

    This report outlines the sources, quantities, characteristics and treatment of transuranic wastes in the United States. This document serves as part of the data base necessary to complete preparation and initiate implementation of transuranic wastes, waste forms, waste container and packaging standards and criteria suitable for inclusion in the present NRC waste management program. No attempt is made to evaluate or analyze the suitability of one technology over another. Indeed, by the nature of this report, there is little critical evaluation or analysis of technologies because such analysis is only appropriate when evaluating a particular application or transuranic waste streams. Due to fiscal restriction, the data base is developed from a myriad of technical sources and does not necessarily contain operating experience and the current status of all technologies. Such an effort was beyond the scope of this report.

  16. Preliminary Results: Release Of Metals From Acid-Mine Drainage Contaminated Streambed Sediments Under Anaerobic Conditions (Presentation)

    Science.gov (United States)

    Many miles of streams in the western U.S. are contaminated with acid-mine drainage (AMD) from abandoned metal mines. Treatment of these streams may include removal of the existing sediments, with subsequent burial (e.g., in a repository). Burial of previously aerobic sediments ma...

  17. Scientific Presenting: Using Evidence-Based Classroom Practices to Deliver Effective Conference Presentations

    Science.gov (United States)

    Corwin, Lisa A.; Prunuske, Amy; Seidel, Shannon B.

    2018-01-01

    Scientists and educators travel great distances, spend significant time, and dedicate substantial financial resources to present at conferences. This highlights the value placed on conference interactions. Despite the importance of conferences, very little has been studied about what is learned from the presentations and how presenters can…

  18. Nuclear electronic components of surface contamination monitor based on multi-electrode proportional counter

    International Nuclear Information System (INIS)

    Du Xiangyang; Zhang Yong; Han Shuping; Rao Xianming; Fang Jintu

    2001-01-01

    The nuclear electronic components applying in Portal Monitor and Hands and Feet Surface Contamination Monitor were based on modern integrated circuit are introduced. The detailed points in circuit design and manufacturing technique are analyzed

  19. Membrane-based seawater desalination: Present and future prospects

    KAUST Repository

    Amy, Gary L.

    2016-10-20

    Given increasing regional water scarcity and that almost half of the world\\'s population lives within 100 km of an ocean, seawater represents a virtually infinite water resource. However, its exploitation is presently limited by the significant specific energy consumption (kWh/m) required by conventional desalination technologies, further exasperated by high unit costs ($/m) and environmental impacts including GHG emissions (g CO-eq/m), organism impingement/entrainment through intakes, and brine disposal through outfalls. This paper explores the state-of-the-art in present seawater desalination practice, emphasizing membrane-based technologies, while identifying future opportunities in step improvements to conventional technologies and development of emerging, potentially disruptive, technologies through advances in material science, process engineering, and system integration. In this paper, seawater reverse osmosis (RO) serves as the baseline conventional technology. The discussion extends beyond desalting processes into membrane-based salinity gradient energy production processes, which can provide an energy offset to desalination process energy requirements. The future membrane landscape in membrane-based desalination and salinity gradient energy is projected to include ultrahigh permeability RO membranes, renewable-energy driven desalination, and emerging processes including closed-circuit RO, membrane distillation, forward osmosis, pressure retarded osmosis, and reverse electrodialysis according various niche applications and/or hybrids, operating separately or in conjunction with RO.

  20. Environmental migration of radium and other contaminants present in liquid and solid wastes from the mining and milling of uranium

    International Nuclear Information System (INIS)

    1986-04-01

    This coordinated research programme has been directed at studying the migration of radium and other contaminants from tailings. It is therefore particularly concerned with the migration and transfer processes caused by ingress of water into tailings piles. Some of the studies in the programme have been concerned with the behaviour of radium after transfer into aquatic systems while others were concerned with the basic processes which occur in tailings piles. Studies of the latter type are essential if the long-term behaviour of radium and other contaminants is to be predicted with confidence and the effects of various treatment schemes are to be understood. The migration behaviour of radium-226, as a precursor to radon-222, will also have an effect on the long-term emission of this gas. The appendices of this report contain the guidance on analysis and measurement procedures and the summaries of research carried out by individual contractors

  1. Radioactive contamination in the Barents Sea, past and present status, uptake of radinuclides in fish and its impact on fisheries

    OpenAIRE

    Føyn, Lars

    1994-01-01

    During the atmospheric nuclear bomb test at the end of the fifties and in the beginning of the sixties the Institute of Marine Research, IMR, monitored the radioactive contamination in commercial landed fish from the Barents Sea. There were indications of an immediate response in uptake of radionuclides depending on the time of the year, probably due to the food situation for the fish. There was also indications of species dependant uptake of radionuclides in fish. Even duri...

  2. Communication-based positioning systems: past, present and prospects

    International Nuclear Information System (INIS)

    Ma Guanyi; Wan Qingtao; Gan Tong

    2012-01-01

    This paper reviews positioning systems in the context of communication systems. First, the basic positioning technique is described for location based service (LBS) in mobile communication systems. Then the high integrity global positioning system (iGPS) is introduced in terms of aspects of what it is and how the low Earth orbit (LEO) Iridium telecommunication satellites enhance the global positioning system (GPS). Emphasis is on the Chinese Area Positioning System (CAPS) which is mainly based on commercial geostationary (GEO) communication satellites, including decommissioned GEO and inclined geosynchronous communication satellites. Characterized by its low cost, high flexibility, wide-area coverage and ample frequency resources, a distinctive feature of CAPS is that its navigation messages are generated on the ground, then uploaded to and forwarded by the communication satellites. Fundamental principles and key technologies applied in the construction of CAPS are presented in detail from the CAPS validation phase to its experimental system setup. A prospective view of CAPS has concluded it to be a seamless, high accuracy, large capacity navigation and communication system which can be achieved by expanding it world wide and enhancing it with LEO satellites and mobile base stations. Hence, this system is a potential candidate for the next generation of radio navigation after GPS. (invited reviews)

  3. Development of custom LCD based portable survey/contamination monitors

    International Nuclear Information System (INIS)

    Reddy, J.D.

    2010-01-01

    Equipments for carrying out radiation survey measurements for alpha, beta and gamma radiations have evolved considerably with the advancements in Electronics overtime. There are 2 major classes of portable instruments available from most manufacturers - (a) Analog indicator type (b) Direct digital readout type. Analog meters give a direct quantifying feel to radiation levels though they are not rich features nor they have smartness like a digital meter. Digital versions have advantages of direct readout numerically and configurable as per users requirements. To achieve best features of both the techniques a dual indicator type LCD module comprising of Analog indicating LCD segments and digital readout indicating 7 segments has been developed. This LCD comprising of LCD glass and its display driver has been deployed across various types of survey meters and contamination monitors manufactured by Nucleonix. This display now facilitates direct readout of dose rate/count rate in various units simultaneously in both analog LCD scale and direct digital indication. (author)

  4. Evaluation of aflatoxins and Aspergillus sp. contamination in raw peanuts and peanut-based products along the supply chain in Malaysia.

    Science.gov (United States)

    Norlia, Mahror; Nor-Khaizura, M A R; Selamat, Jinap; Abu Bakar, Fatimah; Radu, Son; Chin, Cheow Keat

    2018-06-18

    The peanut supply chain in Malaysia is dominated by three main stakeholders (importers, manufacturers, retailers). The present study, aimed to determine the levels and critical points of aflatoxins and fungal contamination in peanuts along the supply chain. Specifically, two types of raw peanuts and six types of peanut-based products were collected (N = 178). Samples were analysed for aflatoxins by using High Performance Liquid Chromatography. Results revealed that the aflatoxins contamination was significantly higher (P≤0.05) in raw peanuts and peanut-based products from the retailers. However, there was no significant different (P≥0.05) in fungal contamination for both types of peanuts except for the total fungal count in raw peanuts from the retailers. Furthermore, raw peanut kernels from the retailers were the most contaminated ones ranged from contamination (0.3 - 3.6 log CFU/g) was relatively higher in raw peanuts compared to that of peanut-based products (0.6 - 2.7 log CFU/g). In conclusion, the manufacturers and retailers were the critical points for aflatoxins contamination in peanuts. However, fungal contamination was more critical in the raw peanuts compared to peanut-based products. The study was limited by a minimal number of samples from the importer. Therefore, further investigations on a larger sample size should be conducted to confirm the findings in this present study.

  5. Stabilization and solidification of a heavy metal contaminated site soil using a hydroxyapatite based binder

    OpenAIRE

    Xia, Wei-Yi; Feng, Ya-Song; Jin, Fei; Zhang, Li-Ming; Du, Yan-Jun

    2017-01-01

    Synthetic hydroxyapatite (HA) is an efficient and environment-friendly material for the remediation of heavy metal contaminated soils. However, the application of conventional HA powder in stabilizing contaminated soils is limited, due to high cost of final products, difficulties in synthesizing purified HA crystals. A new binder named SPC, which composes of single superphosphate (SSP) and calcium oxide (CaO), is presented as an alternative in this study. HA can form in the soil matrix by an ...

  6. EPR and TL-based beta dosimetry measurements in various tooth components contaminated by 90Sr

    International Nuclear Information System (INIS)

    Veronese, I.; Fattibene, P.; Cantone, M.C.; De Coste, V.; Giussani, A.; Onori, S.; Shishkina, E.A.

    2008-01-01

    Thermoluminescence-based beta dosimetry, previously proposed for the estimate of the internal contamination in teeth, and EPR has been used in this paper to investigate the homogeneity of 90 Sr contamination and of dose within nine teeth of one person born in the year of the onset of waterborne radioactive releases of the Mayak plutonium facility. A large deviation of dose and activity distributions in both enamel and radical dentine of the various teeth was observed. Average dose was 27±7Gy in enamel and 0.90±0.31Gy in radical dentine. Average 90 Sr concentration was 52±8Bq/g in enamel and 5±2Bq/g in radical dentine. The observed deviation around the mean value of dose and 90 Sr concentration can be explained due to the specific mineral evolution of each tooth at the time of Sr intake. In the same donor, a negative correlation was also observed between radical dentine and enamel for the 90 Sr specific activity as well for the dose. Similar analyses performed on one massive molar belonging to a second donor revealed absence of correlation between dose and 90 Sr concentration in the same tissue, indicating a dose contribution from 90 Sr present in neighbouring tissue compartments. Systematic differences in cumulated dose and activity levels between the lingual and the buccal parts of crown dentine and of enamel were also observed

  7. Rapid detection of bacterial contamination in cell or tissue cultures based on Raman spectroscopy

    Science.gov (United States)

    Bolwien, Carsten; Sulz, Gerd; Becker, Sebastian; Thielecke, Hagen; Mertsching, Heike; Koch, Steffen

    2008-02-01

    Monitoring the sterility of cell or tissue cultures is an essential task, particularly in the fields of regenerative medicine and tissue engineering when implanting cells into the human body. We present a system based on a commercially available microscope equipped with a microfluidic cell that prepares the particles found in the solution for analysis, a Raman-spectrometer attachment optimized for non-destructive, rapid recording of Raman spectra, and a data acquisition and analysis tool for identification of the particles. In contrast to conventional sterility testing in which samples are incubated over weeks, our system is able to analyze milliliters of supernatant or cell suspension within hours by filtering relevant particles and placing them on a Raman-friendly substrate in the microfluidic cell. Identification of critical particles via microscopic imaging and subsequent image analysis is carried out before micro-Raman analysis of those particles is then carried out with an excitation wavelength of 785 nm. The potential of this setup is demonstrated by results of artificial contamination of samples with a pool of bacteria, fungi, and spores: single-channel spectra of the critical particles are automatically baseline-corrected without using background data and classified via hierarchical cluster analysis, showing great promise for accurate and rapid detection and identification of contaminants.

  8. Estimation of the collective sanitary impact of the land contamination by the radioactivity found at Gif sur Yvette; Estimation de l'impact sanitaire collectif de la contamination des terrains par la radioactivite presente a Gif sur Yvette

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-06-01

    The company 'Societe Nouvelle du Radium' extracted radium and produced radium needles in Gif-sur-Yvette (Essonne) from 1904 to 1957. In 1959, this site was converted into a habitable zone. Since then, this district called the 'Petite Coudraie' has been going through several radioactivity measurements and decontamination works. In 2000, the detection of very high levels of radon above sanitary recommendations in one house encouraged the local authorities to launch a systematic investigation and risk analysis in order to take the necessary measures against radiological risks for the whole concerned district. The 'Direction Departementale des Affaires Sanitaires et Sociales' (D.D.A.S.S.), the French Institute of Public Health (InVS) and the Institute of Nuclear Protection and Security (I.P.S.N.) conducted a health impact assessment of the pollution in this area. The Office for the Protection against Ionizing Radiations (O.P.R.I.) and the I.P.S.N. first measured the radioactivity found on the surface area. The I.P.S.N. then conducted a dosimetric study based on the measurement results and realistic exposure scenarios of adults and children present in the area. Finally, on the base of these results, the InVs did a quantitative risk assessment of cancer due to exposure to the radioactive residuals from the past industrial activities which is the subject of this report. This assessment allows to estimate the extent of this potential health impact due to the contamination of the area with the current scientific knowledge. It assesses the contribution of the various sources ways of exposure to risk and therefore directs the measures of management priority. Finally, it also allows to appreciate the relevance of an epidemiological study on the population who was present in this area. (author)

  9. The Barents Sea, its fisheries and past and present status of radioactive contamination, and its impacts on fisheries

    International Nuclear Information System (INIS)

    Foeyn, L.; Svaeren, I.

    1995-01-01

    For Norway and Russia the fisheries in the Barents Sea is of great importance. When the Chernobyl accident happened, almost two decades had passed without any systematic monitoring of the radioactivity in the Sea. The accident initiated new activity in this field at the Norwegian Institute of Marine Research. In 1990 a programme of sampling sediments, biota and water was started for, in the first hand, determination of radiocesium. The obtained results have shown that the fish resources as such of the Barents Sea have not yet been affected by anthropogenic radioactivity, neither during the nuclear bomb tests in the fifties and sixties, nor during recent years due to accidental releases. The fisheries may, however, be dramatically affected by the fact that the focus of media on radioactive contamination frightens people from eating fish. 11 refs., 1 fig

  10. Linking field-based metabolomics and chemical analyses to prioritize contaminants of emerging concern in the Great Lakes basin

    Science.gov (United States)

    Davis, John M.; Ekman, Drew R.; Teng, Quincy; Ankley, Gerald T.; Berninger, Jason P.; Cavallin, Jenna E.; Jensen, Kathleen M.; Kahl, Michael D.; Schroeder, Anthony L.; Villeneuve, Daniel L.; Jorgenson, Zachary G.; Lee, Kathy E.; Collette, Timothy W.

    2016-01-01

    The ability to focus on the most biologically relevant contaminants affecting aquatic ecosystems can be challenging because toxicity-assessment programs have not kept pace with the growing number of contaminants requiring testing. Because it has proven effective at assessing the biological impacts of potentially toxic contaminants, profiling of endogenous metabolites (metabolomics) may help screen out contaminants with a lower likelihood of eliciting biological impacts, thereby prioritizing the most biologically important contaminants. The authors present results from a study that utilized cage-deployed fathead minnows (Pimephales promelas) at 18 sites across the Great Lakes basin. They measured water temperature and contaminant concentrations in water samples (132 contaminants targeted, 86 detected) and used 1H-nuclear magnetic resonance spectroscopy to measure endogenous metabolites in polar extracts of livers. They used partial least-squares regression to compare relative abundances of endogenous metabolites with contaminant concentrations and temperature. The results indicated that profiles of endogenous polar metabolites covaried with at most 49 contaminants. The authors identified up to 52% of detected contaminants as not significantly covarying with changes in endogenous metabolites, suggesting they likely were not eliciting measurable impacts at these sites. This represents a first step in screening for the biological relevance of detected contaminants by shortening lists of contaminants potentially affecting these sites. Such information may allow risk assessors to prioritize contaminants and focus toxicity testing on the most biologically relevant contaminants. Environ Toxicol Chem 2016;35:2493–2502.

  11. SERS-based application in food analytics (Conference Presentation)

    Science.gov (United States)

    Cialla-May, Dana; Radu, Andreea; Jahn, Martin; Weber, Karina; Popp, Jürgen

    2017-02-01

    To establish detection schemes in life science applications, specific and sensitive methods allowing for fast detection times are required. Due to the interaction of molecules with strong electromagnetic fields excited at metallic nanostructures, the molecular fingerprint specific Raman spectrum is increased by several orders of magnitude. This effect is described as surface-enhanced Raman spectroscopy (SERS) and became a very powerful analytical tool in many fields of application. Within this presentation, we will introduce innovative bottom-up strategies to prepare SERS-active nanostructures coated with a lipophilic sensor layer. To do so, the food colorant Sudan III, an indirect carcinogen substance found in chili powder, palm oil or spice mixtures, is detected quantitatively in the background of the competitor riboflavin as well as paprika powder extracts. The SERS-based detection of azorubine (E122) in commercial available beverages with different complexity (e.g. sugar content, alcohol concentration) illustrates the strong potential of SERS as a qualitative as well as semiquantitative prescan method in food analytics. Here, a good agreement between the estimated concentration employing SERS as well as the gold standard technique HPLC, a highly laborious method, is found. Finally, SERS is applied to detect vitamin B2 and B12 in cereals as well as the estimate the ratio of lycopene and β-carotene in tomatoes. Acknowledgement: Funding the projects "QuantiSERS" and "Jenaer Biochip Initiative 2.0" within the framework "InnoProfile Transfer - Unternehmen Region" the Federal Ministry of Education and Research, Germany (BMBF) is gratefully acknowledged.

  12. The development of halophyte-based agriculture: past and present.

    Science.gov (United States)

    Ventura, Yvonne; Eshel, Amram; Pasternak, Dov; Sagi, Moshe

    2015-02-01

    Freshwater comprises about a mere 2·5% of total global water, of which approximately two-thirds is locked into glaciers at the polar ice caps and on mountains. In conjunction with this, in many instances irrigation with freshwater causes an increase in soil salinity due to overirrigation of agricultural land, inefficient water use and poor drainage of unsuitable soils. The problem of salinity was recognized a long time ago and, due to the importance of irrigated agriculture, numerous efforts have been devoted towards improving crop species for better utilization of saline soils and water. Irrigating plants with saline water is a challenge for practitioners and researchers throughout the world. Recruiting wild halophytes with economic potential was suggested several decades ago as a way to reduce the damage caused by salinization of soil and water. A range of cultivation systems for the utilization of halophytes have been developed, for the production of biofuel, purification of saline effluent in constructed wetlands, landscaping, cultivation of gourmet vegetables, and more. This review critically analyses past and present halophyte-based production systems in the context of genetics, physiology, agrotechnical issues and product value. There are still difficulties that need to be overcome, such as direct germination in saline conditions or genotype selection. However, more and more research is being directed not only towards determining salt tolerance of halophytes, but also to the improvement of agricultural traits for long-term progress. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Detection of seal contamination in heat-sealed food packaging based on active infrared thermography

    Science.gov (United States)

    D'huys, Karlien; Saeys, Wouter; De Ketelaere, Bart

    2015-05-01

    In the food industry packaging is often applied to protect the product from the environment, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the material used and the closure (seal). The material is selected based on the specific needs of the food product to be wrapped. However, proper closure of the package is often harder to achieve. One problem possibly jeopardizing seal quality is the presence of food particles between the seal. Seal contamination can cause a decreased seal strength and thus an increased packaging failure risk. It can also trigger the formation of microchannels through which air and microorganisms can enter and spoil the enclosed food. Therefore, early detection and removal of seal-contaminated packages from the production chain is essential. In this work, a pulsed-type active thermography method using the heat of the sealing bars as an excitation source was studied for detecting seal contamination. The cooling profile of contaminated seals was recorded. The detection performance of four processing methods (based on a single frame, a fit of the cooling profile, pulsed phase thermography and a matched filter) was compared. High resolution digital images served as a reference to quantify contamination. The lowest detection limit (equivalent diameter of 0.63 mm) and the lowest processing time (0.42 s per sample) were obtained for the method based on a single frame. Presumably, practical limitations in the recording stage prevented the added value of active thermography to be fully reflected in this application.

  14. Mannich Bases: An Important Pharmacophore in Present Scenario

    Directory of Open Access Journals (Sweden)

    Suman Bala

    2014-01-01

    Full Text Available Mannich bases are the end products of Mannich reaction and are known as beta-amino ketone carrying compounds. Mannich reaction is a carbon-carbon bond forming nucleophilic addition reaction and is a key step in synthesis of a wide variety of natural products, pharmaceuticals, and so forth. Mannich reaction is important for the construction of nitrogen containing compounds. There is a number of aminoalkyl chain bearing Mannich bases like fluoxetine, atropine, ethacrynic acid, trihexyphenidyl, and so forth with high curative value. The literature studies enlighten the fact that Mannich bases are very reactive and recognized to possess potent diverse activities like anti-inflammatory, anticancer, antifilarial, antibacterial, antifungal, anticonvulsant, anthelmintic, antitubercular, analgesic, anti-HIV, antimalarial, antipsychotic, antiviral activities and so forth. The biological activity of Mannich bases is mainly attributed to α, β-unsaturated ketone which can be generated by deamination of hydrogen atom of the amine group.

  15. Present status of unsealed radioisotope therapy in Japan based on the nation-wide questionnaire

    International Nuclear Information System (INIS)

    Oyamada, Hiyoshimaru

    1999-01-01

    In Japan, clinical application of unsealed radioisotopes is strictly regulated. Especially in the field of therapy, we are allowed to use only Na 131 I at present. Under such circumstances, the present status of therapeutic nuclear medicine in Japan was surveyed by means of a nation-wide questionnaire, conducted in 193 hospitals. Then, 113 hospitals replied to such questionnaire (recovery rate: 58.5%), and it was found that in 77 hospitals, radioisotope therapy is being performed for Graves' disease and/or thyroid cancer. The questionnaire covered the following points: for Graves' disease-the basic strategy of 131 I therapy, its indications, absorbed doses planned to be given, whether the therapy had been conducted on outpatient basis or in-patient basis, method of thyroid weight estimation, interval of administration in case of multiple doses, number of patients treated per year (1996) etc., and for thyroid cancer-strategy for thyroid remnant, the doses to be given, the maximum doses permitted by the authorities in each hospital both per day and per year, handling of highly contaminated urine in each hospital, interval of administration in case of multiple doses, number of patients treated per year (1996) etc. Also questioned were dissatisfaction with the present regulation by the authorities and/or requests for the better daily work, if any. Based on the above questionnaire, the present status of unsealed radioisotope therapy in Japan was investigated. (author)

  16. A Comparative Approach for Ranking Contaminated Sites Based on the Risk Assessment Paradigm Using Fuzzy PROMETHEE

    Science.gov (United States)

    Zhang, Kejiang; Kluck, Cheryl; Achari, Gopal

    2009-11-01

    A ranking system for contaminated sites based on comparative risk methodology using fuzzy Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE) was developed in this article. It combines the concepts of fuzzy sets to represent uncertain site information with the PROMETHEE, a subgroup of Multi-Criteria Decision Making (MCDM) methods. Criteria are identified based on a combination of the attributes (toxicity, exposure, and receptors) associated with the potential human health and ecological risks posed by contaminated sites, chemical properties, site geology and hydrogeology and contaminant transport phenomena. Original site data are directly used avoiding the subjective assignment of scores to site attributes. When the input data are numeric and crisp the PROMETHEE method can be used. The Fuzzy PROMETHEE method is preferred when substantial uncertainties and subjectivities exist in site information. The PROMETHEE and fuzzy PROMETHEE methods are both used in this research to compare the sites. The case study shows that this methodology provides reasonable results.

  17. Method for restoring contaminants to base levels in previously leached formations

    International Nuclear Information System (INIS)

    Strom, E.T.; Espencheid, W.F.

    1983-01-01

    The present invention relates to a method for restoring to environmentally acceptable levels the soluble contaminants in a subterranean formation that has been subjected to oxidative leaching. The contaminants are defined as those ionic species that when subjected to calcium ions form precipitates which are insoluble in the formation fluids. In accordance with the present invention, soluble calcium values are introduced into the formation. The level of contaminants is monitored and when such reaches the desired level, the introduction of soluble calcium values is stopped. The introduction of calcium values may be achieved in several ways one of which is to inject into the formation an aqueous solution containing therein solubilized calcium values. Another method of introducing calcium values into a formation, is to inject into the formation an aqueous solution containing carbon dioxide to solubilize calcium values, such as calcium carbonates, found in the formation

  18. Contamination-free Ge-based graphene as revealed by graphene enhanced secondary ion mass spectrometry (GESIMS)

    Science.gov (United States)

    Michałowski, P. P.; Pasternak, I.; Strupiński, W.

    2018-01-01

    In this study, we demonstrate that graphene grown on Ge does not contain any copper contamination, and identify some of the errors affecting the accuracy of commonly used measurement methods. Indeed, one of these, the secondary ion mass spectrometry (SIMS) technique, reveals copper contamination in Ge-based graphene but does not take into account the effect of the presence of the graphene layer. We have shown that this layer increases negative ionization significantly, and thus yields false results, but also that the graphene enhances, by an order of two, the magnitude of the intensity of SIMS signals when compared with a similar graphene-free sample, enabling much better detection limits. This forms the basis of a new measurement procedure, graphene enhanced SIMS (GESIMS) (pending European patent application no. EP 16461554.4), which allows for the precise estimation of the realistic distribution of dopants and contamination in graphene. In addition, we present evidence that the GESIMS effect leads to unexpected mass interferences with double-ionized species, and that these interferences are negligible in samples without graphene. The GESIMS method also shows that graphene transferred from Cu results in increased copper contamination.

  19. Minimizing the Health Risks from Hydrocarbon Contaminated Soils by Using Electric Field-Based Treatment for Soil Remediation

    Directory of Open Access Journals (Sweden)

    Irina Aura Istrate

    2018-01-01

    Full Text Available The present work addresses the assessment of human health risk from soil contaminated with total petroleum hydrocarbons (TPHs due to crude oil pollution, with a particular focus on the polycyclic aromatic hydrocarbon (PAH group of carcinogenic and toxic substances. Given that the measured risk for human health exceeded the accepted level, the study considered an electrochemical remediation method. The laboratory-scale experiments were conducted by using an electric field-based treatment as a possible solution for the remediation of contaminated soil. After 20 days of treatment, while the voltage applied was 15 V (specific voltage of 1 V/cm, the hydrocarbon content was significantly reduced. The parameters measured to determine the overall remediation efficiency were pH, redox potential, ionic strength, soil characteristics, voltage gradient, and zeta potential. The remediation degree observed during the experiments was around 50% for TPHs and 46% for PAHs. The applied remediation method resulted in significant removal efficiency of the tested contaminants from the soil. Consequently, the human health risk assessment for the new degree of contaminants in the soil was achieved. This data demonstrated to what extent the application of the remediation applied technology ensured an acceptable risk under the same exposure conditions for the industrial workers.

  20. What Is Game-Based Learning? Past, Present, and Future

    Science.gov (United States)

    Jan, Mingfong; Gaydos, Matthew

    2016-01-01

    This article aims at clarifying and conceptualizing game-based learning (GBL) in order to pinpoint directions for practices and research. The authors maintain that GBL should be conceptualized toward the transformation of a textbook-learning culture. The authors emphasize the importance of a paradigm shift in learning and a reorientation in…

  1. New phosphate-based binder for stabilization of soils contaminated with heavy metals: leaching, strength and microstructure characterization.

    Science.gov (United States)

    Du, Yan-Jun; Wei, Ming-Li; Reddy, Krishna R; Jin, Fei; Wu, Hao-Liang; Liu, Zhi-Bin

    2014-12-15

    Cement stabilization is used extensively to remediate soils contaminated with heavy metals. However, previous studies suggest that the elevated zinc (Zn) and lead (Pb) concentrations in the contaminated soils would substantially retard the cement hydration, leading to the deterioration of the performance of cement stabilized soils. This study presents a new binder, KMP, composed of oxalic acid-activated phosphate rock, monopotassium phosphate and reactive magnesia. The effectiveness of stabilization using this binder is investigated on soils spiked with Zn and Pb, individually and together. Several series of tests are conducted including toxicity characteristic leaching (TCLP), ecotoxicity in terms of luminescent bacteria test and unconfined compressive strength. The leachability of a field Zn- and Pb- contaminated soil stabilized with KMP is also evaluated by TCLP leaching test. The results show that the leached Zn concentrations are lower than the China MEP regulatory limit except when Zn and Pb coexist and for the curing time of 7 days. On the other hand, the leached Pb concentrations for stabilized soils with Pb alone or mixed Zn and Pb contamination are much lower than the China MEP or USEPA regulatory limit, irrespective of the curing time. The luminescent bacteria test results show that the toxicity of the stabilized soils has been reduced considerably and is classified as slightly toxic class. The unconfined compressive strength of the soils decrease with the increase in the Zn concentration. The stabilized soils with mixed Zn and Pb contaminants exhibit notably higher leached Zn concentration, while there is lower unconfined compressive strength relative to the soils when contaminated with Zn alone. The X-ray diffraction and scanning electron microscope analyses reveal the presence of bobierrite (Mg3(PO4)2·8H2O) and K-struvite (MgKPO4·6H2O) as the main products formed in the KMP stabilized uncontaminated soils; the formation of hopeite (Zn3(PO4)2·4H2O

  2. An outline of a model-based expert system to identify optimal remedial strategies for restoring contaminated aquatic ecosystems: the project MOIRA

    International Nuclear Information System (INIS)

    Appelgren, A.; Bergstrom, U.; Brittain, J.; Monte, L.

    1996-10-01

    The present report describes the fundamental principles of the research programme MOIRA (a model based computerized system for management support to Identify optimal remedial strategies for Restoring radionuclide contaminated Aquatic ecosystems and drainage areas) financed by the EC (European Community) (Contract N F14P-CT96-0036). The interventions to restore radionuclides contaminated aquatic systems may result in detrimental ecological, social and economical effects. Decision makers must carefully evaluate these impacts. The main aim of the MOIRA project is the development of an expert system based on validated models predicting the evolution of the radioactive contamination of fresh water systems following countermeasure applications and their relevant ecological, social and economical impacts. The expert system will help decision makers, that are not necessarily gifted with experience in environmental modeling, to identify optimal remedial strategies for restoring contaminated fresh water systems

  3. An outline of a model-based expert system to identify optimal remedial strategies for restoring contaminated acquatic ecosystems: The project ``moira``

    Energy Technology Data Exchange (ETDEWEB)

    Appelgren, A.; Bergstrom, U. [Studsvik Eco and AB, Nykoping (Sweden); Brittain, J. [Oslo Univ. (Norway). LFI Zoological Museum; Gallego Diaz, E. [Madrid Universidad Politecnica (Spain). Dept. de Ingenieria Nuclear; Hakanson, L. [KEMA Nuclear, Arnhem (Niger); Monte, L. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dip. Ambiente

    1996-10-01

    The present report describes the fundamental principles of the research programme MOIRA (a model based computerized system for management support to Identify optimal remedial strategies for Restoring radionuclide contaminated Aquatic ecosystems and drainage areas) financed by the EC (European Community) (Contract N F14P-CT96-0036). The interventions to restore radionuclides contaminated aquatic systems may result in detrimental ecological, social and economical effects. Decision makers must carefully evaluate these impacts. The main aim of the MOIRA project is the development of an expert system based on validated models predicting the evolution of the radioactive contamination of fresh water systems following countermeasure applications and their relevant ecological, social and economical impacts. The expert system will help decision makers, that are not necessarily gifted with experience in environmental modeling, to identify optimal remedial strategies for restoring contaminated fresh water systems.

  4. Animal vaccines based on orally presented yeast recombinants.

    Science.gov (United States)

    Shin, Min-Kyoung; Yoo, Han Sang

    2013-09-13

    In veterinary vaccinology, the oral route of administration is an attractive alternative compared to the commonly used parenteral route. Yeasts have a number of properties that make them potential live delivery systems for oral vaccination purposes such as their high expression levels, their GRAS status, adjuvant properties, and post-translational modification possibilities. Consequently, yeasts have been employed for the expression of heterologous genes and for the production of therapeutic proteins. Yeast-based vaccines are reviewed with regard to their ability to express and produce antigens from pathogens for veterinary use. Many of these vaccines have been shown to elicit protective immune responses following oral immunization in animals. Ultimately, yeast-based oral vaccines may offer a potential opportunity for the development of novel ideal vaccines in veterinary medicine. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Competency-Based Postgraduate Medical Education: Past, Present and Future

    Directory of Open Access Journals (Sweden)

    ten Cate, Olle

    2017-11-01

    Full Text Available Since the turn of the twenty-first century, competency-based medical education (CBME has become a dominant approach to postgraduate medical education in many countries. CBME has a history dating back half a century and is rooted in general educational approaches such as outcome-based education and mastery learning. Despite controversies around the terminology and the CBME approach, important national medical regulatory bodies in Canada, the United States, and other countries have embraced CBME. CBME can be characterized as having two distinct features: a focus on specific domains of competence, and a relative independence of time in training, making it an individualized approach that is particularly applicable in workplace training. It is not the length of training that determines a person’s readiness for unsupervised practice, but the attained competence or competencies. This shift in focus makes CBME different from traditional training. In this contribution, definitions of CBME and related concepts are detailed.

  6. Present status of SU(5)-based grand unifications

    International Nuclear Information System (INIS)

    Ahmad, S.M.W.

    1990-10-01

    This paper is a brief communique on the Georgi-Glashow SU(5) paper: Unity of all Elementary Forces, published in 1974; and the other more important papers based on SU(5) or linked with the Georgi-Glashow paper which was welcomed by many a theoretical physicist as a great step. At the end of the paper, a concise review of the experiments (in operation) and the proposed ones is given. (author). 22 refs

  7. Peak AAA Fatty Acid Homolog Contaminants Present in the Dietary Supplement l-Tryptophan Associated with the Onset of Eosinophilia-Myalgia Syndrome.

    Science.gov (United States)

    Klarskov, Klaus; Gagnon, Hugo; Racine, Mathieu; Boudreault, Pierre-Luc; Normandin, Chad; Marsault, Eric; Gleich, Gerald J; Naylor, Stephen

    2018-05-22

    The eosinophilia-myalgia syndrome (EMS) outbreak that occurred in the USA and elsewhere in 1989 was caused by the ingestion of Showa Denko K.K. (SD) L-tryptophan (L-Trp). "Six compounds" detected in the L-Trp were reported as case-associated contaminants. Recently the final and most statistically significant contaminant, "Peak AAA" was structurally characterized. The "compound" was actually shown to be two structural isomers resulting from condensation reactions of L-Trp with fatty acids derived from the bacterial cell membrane. They were identified as the indole C-2 anteiso (AAA 1 -343) and linear (AAA 2 -343) aliphatic chain isomers. Based on those findings, we utilized a combination of on-line HPLC-electrospray ionization mass spectrometry (LC-MS), as well as both precursor and product ion tandem mass spectrometry (MS/MS) to facilitate identification of a homologous family of condensation products related to AAA 1 -343 and AAA 2 -343. We structurally characterized eight new AAA 1 -XXX/AAA 2 -XXX contaminants, where XXX represents the integer molecular ions of all the related homologs, differing by aliphatic chain length and isomer configuration. The contaminants were derived from the following fatty acids of the bacterial cell membrane, 5-methylheptanoic acid (anteiso-C8:0) for AAA 1 -315; n-octanoic acid (n-C8:0) for AAA 2 -315; 6-methyloctanoic acid (anteiso-C9:0) for AAA 1 -329; n-nonanoic acid (n-C9:0) for AAA 2 -329; 10-methyldodecanoic acid (anteiso-C13:0) for AAA 1 -385; n-tridecanoic acid (n-C13:0) for AAA 2 -385; 11-methyltridecanoic acid (anteiso-C14:0) for AAA 1 -399; and n-tetradecanoic acid (n-C14:0) for AAA 2 -399. The concentration levels for these contaminants were estimated to be 0.1 - 7.9 μg / 500 mg of an individual SD L-Trp tablet or capsule The structural similarity of these homologs to case-related contaminants of Spanish Toxic Oil Syndrome (TOS) is discussed. Copyright © 2018. Published by Elsevier B.V.

  8. Lipid Based Nanosystems for Curcumin: Past, Present and Future.

    Science.gov (United States)

    Nayak, Aditya P; Mills, Tom; Norton, Ian

    2016-01-01

    Curcumin is one of the principle bioactive compounds used in the ayurvedic medicine system that has the history of over 5000 years for human use. Curcumin an "Indian Gold" is used to treat simple ailments like the common cold to severe life threatening diseases like cancer, and HIV. Though its contribution is immense for the health protection and disease prevention, its clinical use is limited due to its susceptible nature to alkaline pH, high temperature, presence of oxygen and light. Hence it becomes extremely difficult to maintain its bioactivity during processing, storage and consumption. Recent advancements in the application of nanotechnology to curcumin offer an opportunity to enhance its stability, bioactivity and to overcome its pharmacokinetic mismatch. This in turn helps to bridge the gaps that exist between its bench top research data to its clinical findings. Among the various types of nano/micro delivery systems, lipid based delivery systems are well studied and are the best suited delivery systems to enhance the stability and pharmacokinetic profile of curcumin both for pharma and the food application. In the current review, effort will be made to recapitulate the work done in the past to use lipid based delivery systems (liposomes, solid lipid nanoparticles, and emulsions) to enhance the application of curcumin for health promotion and disease prevention. Further, future prospects for the utilization of these lipid-based delivery systems will be discussed in detail.

  9. Effects of contaminants on reproductive success of aquatic birds nesting at Edwards Air Force Base, California

    Science.gov (United States)

    Hothem, R.L.; Crayon, J.J.; Law, M.A.

    2006-01-01

    Contamination by organochlorine pesticides (OCs), polychlorinated biphenyls, metals, and trace elements at Edwards Air Force Base (EAFB), located in the Mojave Desert, could adversely affect nesting aquatic birds, especially at the sewage lagoons that comprise Piute Ponds. Estimates of avian reproduction, in conjunction with analyses of eggs and avian foods for contaminant residues, may indicate the potential for negative effects on avian populations. From 1996 to 1999, we conducted studies at the Piute Ponds area of EAFB to evaluate the impacts of contaminants on nesting birds. Avian reproduction was evaluated in 1999. Eggs were collected for chemical analyses in 1996 and 1999, and African clawed frogs (Xenopus laevis), a likely food source, were collected for chemical analyses in 1998. Avian species occupying the higher trophic levels-black-crowned night-heron (Nycticorax nycticorax), white-faced ibis (Plegadis chihi), and American avocet (Recurvirostra americana)-generally bioaccumulated higher concentrations of contaminants in their eggs. Reproductive success and egg hatchability of night-herons and white-faced ibises in the Piute Ponds were similar to results observed at other western colonies. Deformities were observed in only one embryo in this study, but concentrations of contaminants evaluated in this ibis embryo were considered insufficient to have caused the deformities. Because clawed frogs, a primary prey item for night-herons at Piute Ponds, had no detectable levels of any OCs, it is likely that OCs found in night-heron eggs were acquired from the wintering grounds rather than from EAFB. The presence of isomers of dichlorodiphenyltrichloroethane (DDT) in ibis eggs indicated recent exposure, but invertebrates used for food by ibises were not sampled at Piute Ponds, and conclusions about the source of OCs in ibis eggs could not be made. Concentrations of contaminants in random and failed eggs of individual species were not different, and we concluded

  10. Mould Contamination of ready-to-eat cereal-based foods retailed in ...

    African Journals Online (AJOL)

    Samples belonging to four different brands (Instant Morvite™, E-Papa™, Ace Instant Porridge™ and Roasted Morvite™) of ready-to-eat fortified cereal-based foodstuffs imported from the Republic of South Africa were bought from different retail outlets in the Roma valley, Lesotho and examined for contamination with ...

  11. Experimental and AI-based numerical modeling of contaminant transport in porous media

    Science.gov (United States)

    Nourani, Vahid; Mousavi, Shahram; Sadikoglu, Fahreddin; Singh, Vijay P.

    2017-10-01

    This study developed a new hybrid artificial intelligence (AI)-meshless approach for modeling contaminant transport in porous media. The key innovation of the proposed approach is that both black box and physically-based models are combined for modeling contaminant transport. The effectiveness of the approach was evaluated using experimental and real world data. Artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) were calibrated to predict temporal contaminant concentrations (CCs), and the effect of noisy and de-noised data on the model performance was evaluated. Then, considering the predicted CCs at test points (TPs, in experimental study) and piezometers (in Myandoab plain) as interior conditions, the multiquadric radial basis function (MQ-RBF), as a meshless approach which solves partial differential equation (PDE) of contaminant transport in porous media, was employed to estimate the CC values at any point within the study area where there was no TP or piezometer. Optimal values of the dispersion coefficient in the advection-dispersion PDE and shape coefficient of MQ-RBF were determined using the imperialist competitive algorithm. In temporal contaminant transport modeling, de-noised data enhanced the performance of ANN and ANFIS methods in terms of the determination coefficient, up to 6 and 5%, respectively, in the experimental study and up to 39 and 18%, respectively, in the field study. Results showed that the efficiency of ANFIS-meshless model was more than ANN-meshless model up to 2 and 13% in the experimental and field studies, respectively.

  12. Biochar based remediation of water and soil contaminated by phenanthrene and pentachlorophenol.

    Science.gov (United States)

    Rao, Maria A; Di Rauso Simeone, Giuseppe; Scelza, Rosalia; Conte, Pellegrino

    2017-11-01

    Phenanthrene (Phe) and pentachlorophenol (PCP) are classified as persistent organic pollutants and represent serious concern for the environment as they are toxic and ubiquitous. Biochar based remediation is an emerging technology used in water and soil contamination. In this study we used poplar (BP) and conifer (BC) biochars to remediate water and soil contaminated by Phe and PCP. BP and BC were able to remove completely either Phe or PCP from contaminated water within one to three days. When biochar was confined in a porous membrane, BC and BP maintained their sorption efficiency for several remediation cycles. However, in these conditions BC allowed faster Phe removal. In soil remediation experiments, addition of two biochar rates, i.e. 2.5 and 5 mg g -1 , strongly reduced Phe extractability (up to 2.7% of the initially added Phe with the larger BC dose). This was similar to the behavior observed when compost was applied in order to verify the role of soil organic matter in the fate of both contaminants. PCP extractability was reduced only up to 75% (in average) in all samples including those with compost amendment. Only larger amount of biochar (20 and 50 mg g -1 ) allowed reduction of the extractable PCP and nullified phytotoxicity of the contaminant. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effects-based spatial assessment of contaminated estuarine sediments from Bear Creek, Baltimore Harbor, MD, USA.

    Science.gov (United States)

    Hartzell, Sharon E; Unger, Michael A; McGee, Beth L; Wilson, Sacoby M; Yonkos, Lance T

    2017-10-01

    Estuarine sediments in regions with prolonged histories of industrial activity are often laden to significant depths with complex contaminant mixtures, including trace metals and persistent organic pollutants. Given the complexity of assessing risks from multi-contaminant exposures, the direct measurement of impacts to biological receptors is central to characterizing contaminated sediment sites. Though biological consequences are less commonly assessed at depth, laboratory-based toxicity testing of subsurface sediments can be used to delineate the scope of contamination at impacted sites. The extent and depth of sediment toxicity in Bear Creek, near Baltimore, Maryland, USA, was delineated using 10-day acute toxicity tests with the estuarine amphipod Leptocheirus plumulosus, and chemical analysis of trace metals and persistent organic pollutants. A gradient of toxicity was demonstrated in surface sediments with 21 of 22 tested sites differing significantly from controls. Effects were most pronounced (100% lethality) at sites proximate to a historic industrial complex. Sediments from eight of nine core samples to depths of 80 cm were particularly impacted (i.e., caused significant lethality to L. plumulosus) even in locations overlain with relatively non-toxic surface sediments, supporting a conclusion that toxicity observed at the surface (top 2 cm) does not adequately predict toxicity at depth. In seven of nine sites, toxicity of surface sediments differed from toxicity at levels beneath by 28 to 69%, in five instances underestimating toxicity (28 to 69%), and in two instances overestimating toxicity (44 to 56%). Multiple contaminants exceeded sediment quality guidelines and correlated positively with toxic responses within surface sediments (e.g., chromium, nickel, polycyclic aromatic hydrocarbon (PAH), total petroleum hydrocarbon). Use of an antibody-based PAH biosensor revealed that porewater PAH concentrations also increased with depth at most sites. This

  14. Comparing SVM and ANN based Machine Learning Methods for Species Identification of Food Contaminating Beetles.

    Science.gov (United States)

    Bisgin, Halil; Bera, Tanmay; Ding, Hongjian; Semey, Howard G; Wu, Leihong; Liu, Zhichao; Barnes, Amy E; Langley, Darryl A; Pava-Ripoll, Monica; Vyas, Himansu J; Tong, Weida; Xu, Joshua

    2018-04-25

    Insect pests, such as pantry beetles, are often associated with food contaminations and public health risks. Machine learning has the potential to provide a more accurate and efficient solution in detecting their presence in food products, which is currently done manually. In our previous research, we demonstrated such feasibility where Artificial Neural Network (ANN) based pattern recognition techniques could be implemented for species identification in the context of food safety. In this study, we present a Support Vector Machine (SVM) model which improved the average accuracy up to 85%. Contrary to this, the ANN method yielded ~80% accuracy after extensive parameter optimization. Both methods showed excellent genus level identification, but SVM showed slightly better accuracy  for most species. Highly accurate species level identification remains a challenge, especially in distinguishing between species from the same genus which may require improvements in both imaging and machine learning techniques. In summary, our work does illustrate a new SVM based technique and provides a good comparison with the ANN model in our context. We believe such insights will pave better way forward for the application of machine learning towards species identification and food safety.

  15. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio

    International Nuclear Information System (INIS)

    1992-04-01

    This Removal Action System Design has been prepared as a Phase I Volume for the implementation of the Phase II removal action at Wright-Patterson Air Force Base (WPAFB) near Dayton, Ohio. The objective of the removal action is to prevent, to the extent practicable, the migration of ground water contaminated with chlorinated volatile organic compounds (VOCS) across the southwest boundary of Area C. The Phase 1, Volume 9 Removal Action System Design compiles the design documents prepared for the Phase II Removal Action. These documents, which are presented in Appendices to Volume 9, include: Process Design, which presents the 30 percent design for the ground water treatment system (GWTS); Design Packages 1 and 2 for Earthwork and Road Construction, and the Discharge Pipeline, respectively; no drawings are included in the appendix; Design Package 3 for installation of the Ground Water Extraction Well(s); Design Package 4 for installation of the Monitoring Well Instrumentation; and Design Package 5 for installation of the Ground Water Treatment System; this Design Package is incorporated by reference because of its size

  16. Overcoming etch challenges related to EUV based patterning (Conference Presentation)

    Science.gov (United States)

    Metz, Andrew W.; Cottle, Hongyun; Honda, Masanobu; Morikita, Shinya; Kumar, Kaushik A.; Biolsi, Peter

    2017-04-01

    Research and development activities related to Extreme Ultra Violet [EUV] defined patterning continue to grow for cost and extreme process control challenges of Self-Aligned Quad Patterning [SAQP] with continued momentum for EUV ecosystem readiness could provide cost advantages in addition to improved intra-level overlay performance relative to multiple patterning approaches. However, Line Edge Roughness [LER] and Line Width Roughness [LWR] performance of EUV defined resist images are still far from meeting technology needs or ITRS spec performance. Furthermore, extreme resist height scaling to mitigate flop over exacerbates the plasma etch trade-offs related to traditional approaches of PR smoothing, descum implementation and maintaining 2D aspect ratios of short lines or elliptical contacts concurrent with ultra-high photo resist [PR] selectivity. In this paper we will discuss sources of LER/LWR, impact of material choice, integration, and innovative plasma process techniques and describe how TELTM VigusTM CCP Etchers can enhance PR selectivity, reduce LER/LWR, and maintain 2D aspect ratio of incoming patterns. Beyond traditional process approaches this paper will show the utility of: [1] DC Superposition in enhancing EUV resist hardening and selectivity, increasing resistance to stress induced PR line wiggle caused by CFx passivation, and mitigating organic planarizer wiggle; [2] Quasi Atomic Layer Etch [Q-ALE] for ARC open eliminating the tradeoffs between selectivity, CD, and shrink ratio control; and [3] ALD+Etch FUSION technology for feature independent CD shrink and LER reduction. Applicability of these concepts back transferred to 193i based lithography is also confirmed.

  17. Toward efficient fiber-based quantum interface (Conference Presentation)

    Science.gov (United States)

    Soshenko, Vladimir; Vorobyov, Vadim V.; Bolshedvorsky, Stepan; Lebedev, Nikolay; Akimov, Alexey V.; Sorokin, Vadim; Smolyaninov, Andrey

    2016-04-01

    , vol. 528, no. 1, p. 1-45, 2013. [2] A.V. Akimov, A. Mukherjee, C.L. Yu, D.E. Chang, A.S. Zibrov, P.R. Hemmer, H. Park and M.D. Lukin, "Generation of single optical plasmons in metallic nanowires coupled to quantum dots," Nature, vol. 450, p. 402-406, 2007. [3] Michael J. Burek , Yiwen Chu, Madelaine S.Z. Liddy, Parth Patel, Jake Rochman , Srujan Meesala, Wooyoung Hong, Qimin Quan, Mikhail D. Lukin and Marko Loncar High quality-factor optical nanocavities in bulk single-crystal diamond, Nature communications 6718 (2014) [4] Tim Schroder, Andreas W. Schell, Gunter Kewes, Thomas Aichele, and Oliver Benson Fiber-Integrated Diamond-Based Single Photon Source, Nano Lett. 2011, 11, 198-202 [5]Lars Liebermeister, et. al. "Tapered fiber coupling of single photons emitted by a deterministically positioned single nitrogen vacancy center", Appl. Phys. Lett. 104, 031101 (2014)

  18. Development of sustainable Palladium-based catalysts for removal of persistent contaminants from drinking water

    Science.gov (United States)

    Shuai, Danmeng

    Pd-based catalytic reduction has emerged as an advanced treatment technology for drinking water decontamination, and a suite of persistent contaminants including oxyanions, N-nitrosoamines, and halogenated compounds are amenable to catalytic reduction. The primary goal of this study is to develop novel Pd-based catalysts with enhanced performance (i.e., activity, selectivity, and sustainability) to remove contaminants from drinking water. The effects of water quality (i.e., co-contaminants in water matrix), catalyst support, and catalyst metal were explored, and they provide insights for preparing catalysts with faster kinetics, higher selectivity, and extended lifetime. Azo dyes are wide-spread contaminants, and they are potentially co-exisiting with target contaminants amenable for catalytic removal. The probe azo dye methyl orange (MO) enhanced catalytic reduction kinetics of a suite of oxyanions (i.e., nitrate, nitrite, bromate, chlorate, and perchlorate) and diatrizoate significantly but not N-nitrosodimethylamine (NDMA) with a variety of Pd-based catalysts. Nitrate was selected as a probe contaminant, and several different azo dyes (i.e., (methyl orange, methyl red, fast yellow AB, metanil yellow, acid orange 7, congo red, eriochrome black T, acid red 27, acid yellow 11, and acid yellow 17) were evaluated for their ability to enhance reduction. A hydrogen atom shuttling mechanism was proposed and a kinetic model was proposed based on Bronsted-Evans-Polanyi (BEP) theory, and they suggest sorbed azo dyes and reduced hydrazo dyes shuttle hydrogen atoms to oxyanions or diatrizoate to enhance their reduction kinetics. Next, vapor-grown carbon nanofiber (CNF) supports were used to explore the effects of Pd nanoparticle size and interior versus exterior loading on nitrite reduction activity and selectivity (i.e., dinitrogen over ammonia production). In order to evaluate the amount of interior versus exterior loading of Pd nanoparticles, a fast and accurate geometric

  19. The field application of an immunoassay-based test for petroleum fuels contamination in groundwater

    International Nuclear Information System (INIS)

    Carter, K.R.

    1994-01-01

    The recent development of low-cost, rapid field analytical tests for petroleum fuels based on immunoassay technology has provided an on-site tool for the cost-effective, accurate assessment of groundwater contamination. The method allows for rapid, direct measurement of contaminant concentration. The method has been used for a variety of applications including surface water runoff testing and groundwater monitoring well siting. The PETRO RISc Water Test can be used to substantially reduce the cost of monitoring well installation. Current, monitoring wells are placed based on knowledge of the location of the source of contamination, the size of the release, the time elapsed since the release began, and the hydrogeology of the site. While the location of the source is generally known with some precision, the hydrogeology of the site and the timing of the release rarely are. This results in the need for an ''educated guess'' regarding the drilling location for monitoring wells that are installed to provide long term feedback on groundwater contamination. The tests have the greatest sensitivity to aliphatic compounds in the range of six to ten carbons and aromatic compounds such as toluene, xylene, and naphthalene

  20. Global assessment of exposure to faecal contamination through drinking water based on a systematic review.

    Science.gov (United States)

    Bain, Robert; Cronk, Ryan; Hossain, Rifat; Bonjour, Sophie; Onda, Kyle; Wright, Jim; Yang, Hong; Slaymaker, Tom; Hunter, Paul; Prüss-Ustün, Annette; Bartram, Jamie

    2014-08-01

    To estimate exposure to faecal contamination through drinking water as indicated by levels of Escherichia coli (E. coli) or thermotolerant coliform (TTC) in water sources. We estimated coverage of different types of drinking water source based on household surveys and censuses using multilevel modelling. Coverage data were combined with water quality studies that assessed E. coli or TTC including those identified by a systematic review (n = 345). Predictive models for the presence and level of contamination of drinking water sources were developed using random effects logistic regression and selected covariates. We assessed sensitivity of estimated exposure to study quality, indicator bacteria and separately considered nationally randomised surveys. We estimate that 1.8 billion people globally use a source of drinking water which suffers from faecal contamination, of these 1.1 billion drink water that is of at least 'moderate' risk (>10 E. coli or TTC per 100 ml). Data from nationally randomised studies suggest that 10% of improved sources may be 'high' risk, containing at least 100 E. coli or TTC per 100 ml. Drinking water is found to be more often contaminated in rural areas (41%, CI: 31%-51%) than in urban areas (12%, CI: 8-18%), and contamination is most prevalent in Africa (53%, CI: 42%-63%) and South-East Asia (35%, CI: 24%-45%). Estimates were not sensitive to the exclusion of low quality studies or restriction to studies reporting E. coli. Microbial contamination is widespread and affects all water source types, including piped supplies. Global burden of disease estimates may have substantially understated the disease burden associated with inadequate water services. © 2014 The Authors. Tropical Medicine and International Health published by John Wiley & Sons Ltd.

  1. Determination of ultra-trace contaminants on silicon wafer surfaces using TXRF. Present state of the art

    International Nuclear Information System (INIS)

    Pahlke, S.; Fabry, L.; Kotz, L.; Mantler, C.; Ehmann, T.

    2000-01-01

    Recently, TXRF became a standard, on-line inspection tool for controlling the cleanliness of polished Si wafers for semiconductor use now up to 300 diameter. Wafer makers strive for an all-over metallic cleanliness of 10 atoms x cm -2 . Therefore an analytical tools must cover LOD in a range 9 atoms x cm -2 or lower. The all-over cleanliness of the whole wafer surface can analyzed using VPD/TXRF. For this chemical wafer-pre-preparation under cleanroom conditions class 1 we have developed a full automatic 'Wafer Surface Preparation System' coupled with a new generation TXRF. We have also combined this system with other independent methods for Na, Al, anions and cations. Only the combination of automatic wafer handling systems, modem analytical tools, ultra-pure water, ULSI chemicals and special cleanroom conditions provides us a chance to achieve the present and the future demands for semiconductor industry. (author)

  2. Influence of base pressure and atmospheric contaminants on a-Si:H solar cell properties

    International Nuclear Information System (INIS)

    Woerdenweber, J.; Schmitz, R.; Mueck, A.; Zastrow, U.; Niessen, L.; Gordijn, A.; Carius, R.; Beyer, W.; Rau, U.; Merdzhanova, T.; Stiebig, H.

    2008-01-01

    The influence of atmospheric contaminants oxygen and nitrogen on the performance of thin-film hydrogenated amorphous silicon (a-Si:H) solar cells grown by plasma-enhanced chemical vapor deposition at 13.56 MHz was systematically investigated. The question is addressed as to what degree of high base pressures (up to 10 -4 Torr) are compatible with the preparation of good quality amorphous silicon based solar cells. The data show that for the intrinsic a-Si:H absorber layer exists critical oxygen and nitrogen contamination levels (about 2x10 19 atoms/cm 3 and 4x10 18 atoms/cm 3 , respectively). These levels define the minimum impurity concentration that causes a deterioration in solar cell performance. This critical concentration is found to depend little on the applied deposition regime. By enhancing, for example, the flow of process gases, a higher base pressure (and leak rate) can be tolerated before reaching the critical contamination level. The electrical properties of the corresponding films show that increasing oxygen and nitrogen contamination results in an increase in dark conductivity and photoconductivity, while activation energy and photosensitivity are decreased. These effects are attributed to nitrogen and oxygen induced donor states, which cause a shift of the Fermi level toward the conduction band and presumably deteriorate the built-in electric field in the solar cells. Higher doping efficiencies are observed for nitrogen compared to oxygen. Alloying effects (formation of SiO x ) are observed for oxygen contaminations above 10 20 atoms/cm 3 , leading to an increase in the band gap

  3. On-site radioactive soil contamination at the Andreeva Bay shore technical base, Northwest Russia.

    Science.gov (United States)

    Reistad, O; Dowdall, M; Selnaes, Ø G; Standring, W J F; Hustveit, S; Steenhuisen, F; Sørlie, A

    2008-07-01

    The radioactive waste (RAW) storage site at Andreeva Bay in the Russian Northwest has experienced radioactive contamination both as a result of activities carried out at the site and due to incidents that have occurred there in the past such as accidental releases of radioactive materials. The site is an interesting case study for decommissioning due to the extremely large amounts of radioactivity present at the site and the conditions under which it is stored; very little has been previously published in the scientific literature about this site. This paper complements the paper describing dose rates at Andreeva Bay which is published in this issue of Journal of Environmental Radioactivity by the same authors. This study presents new data related to the activity concentrations of (137)Cs and (90)Sr in surface soils and measurements of alpha- and beta-particle fluxes taken at different areas around the site. Limited data on 60Co is also presented. The results of the study indicate that the main areas of site contamination are associated with the former spent nuclear fuel storage facility at Building 5, due to accidental discharges which began in 1982. Substantial contamination is also observed at the solid radioactive waste storage facilities, probably due to the ingress of water into these facilities. More than 240 samples were measured: maximum contamination levels were 1 x 10(6)Bq/kg (137)Cs (mean value 4.1 x 10(5)Bq/kg) and 4 x 10(6)Bq/kg (90)Sr (mean value 1.2 x1 0(5)Bq/kg). Localised patches of alpha and beta contamination were also observed throughout the site.

  4. Assessment of the present and future implications of radioactive contamination of the Irish Sea coastal region of Cumbria

    International Nuclear Information System (INIS)

    Wilkins, B.T.; Simmonds, J.R.; Cooper, J.R.

    1994-10-01

    An assessment has been made of the doses that could be received by people who make use of the Cumbrian coastal area. Current doses have been estimated for residents and visitors to different parts of the area. By making assumptions about changes in waste management practices at the BNFL Sellafield plant and in the geography of the coastal area, the development of doses over the next 200 years has been assessed. The study was confined to exposure pathways in the terrestrial environment, although the influence of liquid discharges on terrestrial pathways was taken into account. Consumption of marine foodstuffs was outside the scope of the study. As expected, the highest doses would be received by those people who live closest to Sellafield. However, in all cases doses to average individuals were well below the present limit for members of the public specified by ICRP. The general future trend was for doses to decline. Doses were also estimated for particular population groups such as those who spend more time on beaches. While the resultant values were higher than those for average individuals, they were still well within the ICRP limit in all cases. (author)

  5. Identification of the source of PFOS and PFOA contamination at a military air base site.

    Science.gov (United States)

    Arias E, Victor A; Mallavarapu, Megharaj; Naidu, Ravi

    2015-01-01

    Although the use of perfluorooctane sulfonic acid (PFOS)/perfluorooctanoic acid (PFOA)-based aqueous fire-fighting foams (AFFF) has been banned due to their persistence, bioaccumulation and toxicity to biota, PFOS and PFOA are still present at significant levels in the environment due to their past usage. This study investigated the reasons for detection of PFOS and PFOA in an evaporation pond used to collect the wastewater arising from fire-fighting exercises at a military air base despite the replacement of PFOS/PFOA-based foam with no PFOS/PFOA-foam about 6 years ago. Concentrations in the wastewater stored in this pond ranged from 3.6 to 9.7 mg/L for PFOS and between 0.6 and 1.7 mg/L for PFOA. The hypothesis tested in a laboratory study was that PFOS and PFOA have accumulated in the sediments of the pond and can be released into the main body of the water. Concentrations detected in the sediments were 38 and 0.3 mg/g for PFOS and PFOA, respectively. These values exceed the recently reported average global values for sediments (0.2-3.8 ng/g for PFOS and from 0.1 to 0.6 ng/g for PFOA) by a factor of several thousands. PFOS and PFOA distribution coefficients were derived for the organic content of the pond sediment (1.6%). Identification of the source of contamination and knowledge of the partition between soil and aqueous phases are vital first steps in developing a sustainable remediation technology to remove the source from the site. This study clearly suggests that unless the sediment is cleaned of PFOS/PFOA, these chemicals will continue to be detected for a long period in the pond water, with potential adverse impacts on the ecosystem.

  6. Reinterpreting the importance of oxygen-based biodegradation in chloroethene-contaminated groundwater

    Science.gov (United States)

    Bradley, Paul M.

    2011-01-01

    Chlororespiration is common in shallow aquifer systems under conditions nominally identified as anoxic. Consequently, chlororespiration is a key component of remediation at many chloroethene-contaminated sites. In some instances, limited accumulation of reductive dechlorination daughter products is interpreted as evidence that natural attenuation is not adequate for site remediation. This conclusion is justified when evidence for parent compound (tetrachloroethene, PCE, or trichloroethene, TCE) degradation is lacking. For many chloroethene-contaminated shallow aquifer systems, however, nonconservative losses of the parent compounds are clear but the mass balance between parent compound attenuation and accumulation of reductive dechlorination daughter products is incomplete. Incomplete mass balance indicates a failure to account for important contaminant attenuation mechanisms and is consistent with contaminant degradation to nondiagnostic mineralization products like CO2. While anoxic mineralization of chloroethene compounds has been proposed previously, recent results suggest that oxygen-based mineralization of chloroethenes also can be significant at dissolved oxygen concentrations below the currently accepted field standard for nominally anoxic conditions. Thus, reassessment of the role and potential importance of low concentrations of oxygen in chloroethene biodegradation are needed, because mischaracterization of operant biodegradation processes can lead to expensive and ineffective remedial actions. A modified interpretive framework is provided for assessing the potential for chloroethene biodegradation under different redox conditions and the probable role of oxygen in chloroethene biodegradation.

  7. Radiobiological significance of radioactive contamination - summary assessment based on great number of measurements

    International Nuclear Information System (INIS)

    Angelov, V.; Bonchev, Ts.; Mavrodiev, V.; Kyrdzhilov, N.

    1995-01-01

    In order to facilitate quantitative and qualitative characterisation of radioactive contamination the authors introduce a relative estimate of radionuclide activity by setting as a reference the most abundant element -Co-60 in the case of the Kozloduy NPP. The ratio η i of the mean annual permissible concentration in air for each radionuclide (RPC-92) to that of Co-60 is calculated. It is found that η i has the same or close values for groups of radionuclides, e.g. η i = 2.10 -4 for 238 Pu, 239 Pu, 240 Pu, 241 Am, 244 Cm; η i = 5 for 89 Sr, 91 Y; 93 Nb, 134 Cs, 137 Cs; η i = 50 for 55 Fe, 63 Ni, 95 Zr, 95 Nb, 140 Ba, 140 La. Then it is compared to the experimentally measured values of the same quantity η iexp , derived from surface contamination data. The ratio η iexp /η i is plotted against log η i . The resulting nomograms give graphic representation of the radiobiological significance of various radionuclide groups. Data from different locations at the Kozloduy NPP are presented. It is found that the alpha emitter contamination has highest values in the Unit 1 (WWER-440) control rooms after repair. The Unit 5 (WWER-1000) has lower alpha contamination compared to WWER-440 units. 1 ref., 5 figs., 1 tab

  8. Assessing and minimizing contamination in time of flight based validation data

    Science.gov (United States)

    Lennox, Kristin P.; Rosenfield, Paul; Blair, Brenton; Kaplan, Alan; Ruz, Jaime; Glenn, Andrew; Wurtz, Ronald

    2017-10-01

    Time of flight experiments are the gold standard method for generating labeled training and testing data for the neutron/gamma pulse shape discrimination problem. As the popularity of supervised classification methods increases in this field, there will also be increasing reliance on time of flight data for algorithm development and evaluation. However, time of flight experiments are subject to various sources of contamination that lead to neutron and gamma pulses being mislabeled. Such labeling errors have a detrimental effect on classification algorithm training and testing, and should therefore be minimized. This paper presents a method for identifying minimally contaminated data sets from time of flight experiments and estimating the residual contamination rate. This method leverages statistical models describing neutron and gamma travel time distributions and is easily implemented using existing statistical software. The method produces a set of optimal intervals that balance the trade-off between interval size and nuisance particle contamination, and its use is demonstrated on a time of flight data set for Cf-252. The particular properties of the optimal intervals for the demonstration data are explored in detail.

  9. Schiff base: A high affinity chemical agent to decrease the concentration of aflatoxin M1 in raw milk contaminated artificially

    Directory of Open Access Journals (Sweden)

    Frane Delaš

    2012-03-01

    Full Text Available In the present study were conducted the effect of pH (5.5, 6.0 and 6.5 and concentration of new synthesized 3-/2-aminophenylimino-(p-toluoyl/-4-hydroxy-6-(p-tolyl-2H-pyrane-2-one (Schiff base on decrease the concentration of aflatoxin M1 (AFM1 in raw milk contaminated with known concentration of this toxin. Experiments were carried out at temperature of 4 °C during 35 days. At pH 5.5 Schiff base concentration of 0.1 µmol/L was lessening the concentration of AFM1 after 35 days by 55 %. However, at pH 6.5 the most effective concentration for lessening of AFM1 was 0.5 µmol/L. Schiff base was not effective at pH value of 7 or higher. The ability of Schiff base to act as antimycotoxigenic agent provides new perspective for possibly using this compound to control AFM1 contamination in milk and to extent shelf lives of this food. Detection of toxicity of investigated Schiff base was performed by using the brine shrimp (Artemia salina larvae as an biological indicator to determine their sensitivity to this chemical agent.

  10. A Risk-Based Characterization of Sediment Contamination by Legacy and Emergent Contaminants of Concern in Coastal British Columbia, Canada.

    Science.gov (United States)

    Morales-Caselles, Carmen; Desforges, Jean-Pierre W; Dangerfield, Neil; Ross, Peter S

    2017-08-01

    Sediments have long been used to help describe pollution sources, contaminated sites, trends over time, and habitat quality for marine life. We collected surficial sediments from 12 sites at an average seawater depth of 25 m in three near-urban areas of the Salish Sea (British Columbia, Canada) to investigate habitat quality for marine life, including heavily contaminated killer whales. Samples were analyzed using high-resolution instrumentation for a wide variety of congeners of polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs), hexabromocyclododecane (HBCDD), polybrominated biphenyls, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans, organochlorine pesticides, and polychlorinated naphthalenes (PCNs). The top six contaminant classes detected in sediments were ∑PCB > ∑PBDE > ∑PCDD/F > DDT > ∑HBCDD > ∑PCN. Near-urban harbor sediments had up to three orders of magnitude higher concentrations of contaminants than more remote sites. With limited tools available to characterize biological risks associated with complex mixtures in the real world, we applied several available approaches to prioritize the pollutant found in our study: (1) sediment quality guidelines from the Canadian Council of Ministers of the Environment where available; (2) US NOAA effects range low and other international guidelines; (3) total TEQ for dioxin-like PCBs for the protection of mammals; and (4) the calculation of risk quotients. Our findings provide an indication of the state of contamination of coastal environments in British Columbia and guidance for chemical regulations and priority setting, as well as management actions including best-practices, dredging, disposal at sea, and source control. In this regard, the legacy PCB and the emergent PBDEs should command continued priority monitoring.

  11. Study on Contaminant Transportation of a Typical Chemical Industry Park Based on GMS Software

    Science.gov (United States)

    Huang, LinXian; Liu, GuoZhen; Xing, LiTing; Liu, BenHua; Xu, ZhengHe; Yang, LiZhi; Zhu, HebgHua

    2018-03-01

    The groundwater solute transport model can effectively simulated the transport path, the transport scope, and the concentration of contaminant which can provide quantitative data for groundwater pollution repair and groundwater resource management. In this study, we selected biological modern technology research base of Shandong province as research objective and simulated the pollution characteristic of typicalcontaminant cis-1, 3-dichloropropene under different operating conditions by using GMS software.

  12. Risk assessment based on current release standards for radioactive surface contamination

    International Nuclear Information System (INIS)

    Chen, S.Y.

    1993-09-01

    Standards for uncontrolled releases of radioactive surface contamination have been in existence in the United States for about two decades. Such standards have been issued by various agencies, including the US Department of Energy. This paper reviews the technical basis of published standards, identifies areas in need of revision, provides risk interpretations based on current technical knowledge and the regulatory environment, and offers suggestions for improvements

  13. Dose reconstruction in radioactively contaminated areas based on radiation transport calculations and measurements

    International Nuclear Information System (INIS)

    Hiller, Mauritius Michael

    2015-01-01

    The external radiation exposure at the former village of Metlino, Russia, was reconstructed. The Techa river in Metlino was contaminated by water from the Majak plant. The village was evacuated in 1956 and a reservoir lake created. Absorbed doses in bricks were measured and a model of the present-day and the historic Metlino was created for Monte Carlo calculations. By combining both, the air kerma at shoreline could be reconstructed to evaluate the Techa River Dosimetry System.

  14. Use of cement-fly ash-based stabilization techniques for the treatment of waste containing aromatic contaminants

    Science.gov (United States)

    Banaszkiewicz, Kamil; Marcinkowski, Tadeusz

    2017-11-01

    Research on evaluation of evaporation rate of volatile organic compounds from soil beds during processing is presented. For the experiment, soil samples were prepared with the same amounts of benzene and stabilized using a mixture of CEMI 42.5R cement and fly ash from pit-coal combustion. Solidification of soils contaminated with BTEX hydrocarbons using hydraulic binders involves a risk of releasing vapours of these compounds during homogenization of waste with stabilizing mixture introduced and its dilution with water. The primary purposes of the research were: analysis of benzene volume emitted from soil during stabilization/solidification process and characterization of factors that may negatively affect the quality of measurements/the course of stabilization process. Analysis of benzene emission intensity during the process was based on concentration (C6H6) values, recorded with flame-ionization detector above the surface of reacting mixture. At the same time, gaseous contaminants emitted during waste stabilization were passed through pipes filled with activated carbon (SCK, Anasorb CSC). Benzene vapours adsorbed on activated carbon were subjected to analysis using gas chromatograph Varian 450-GC. Evaporation characteristics of benzene during processing contaminated soils revealed the stages creating the highest danger to workers' health, as well as a need for actions connected with modification of technological line.

  15. INITIAL AND PRESENT SITUATION OF FOOD CONTAMINATION IN JAPAN AFTER THE ACCIDENT AT THE FUKUSHIMA DAI-ICHI NUCLEAR POWER PLANT.

    Science.gov (United States)

    Aono, Tatsuo; Yoshida, Satoshi; Akashi, Makoto

    2016-09-01

    The accident at the Fukushima Dai-ichi Nuclear Power Plant (NPP) in March 2011 affected not only the terrestrial environment of Fukushima prefecture and the surrounding area, but also the marine area facing the NPP. Our present study is focused on the concentrations of radionuclides in agricultural products of Fukushima and sea-foods collected off Fukushima after the accident. The regulation value for radiocesium in vegetables, meat and fish was revised from 500 Bq/kg-wet to 100 Bq/kg-wet on 1 April 2012. The overall activity of radiocesium in these products was found to be within the limit of tolerance in respect to Japanese and also international regulations, but there is still radiocesium found at activities greater than this level in edible wild plants, wild mushrooms and game such as boar meat. Although the activities of radionuclides exceeding the regulatory limits were not detected in marine products collected off Fukushima after April 2015, the commercial marine fishery has not received approval in the affected areas except for certain species. We learned from the Fukushima accident that long-term kinetic studies of radionuclides in terrestrial and marine environments is extremely important for prevention of internal contamination, since contamination with radionuclides occurs via the food chain in the environment. © World Health Organisation 2016. All rights reserved. The World Health Organization has granted Oxford University Press permission for the reproduction of this article.

  16. Initial and present situation of food contamination in Japan after the accident at the Fukushima Dai-Ichi Nuclear Power Plant

    International Nuclear Information System (INIS)

    Aono, Tatsuo; Yoshida, Satoshi; Akashi, Makoto

    2016-01-01

    The accident at the Fukushima Dai-ichi Nuclear Power Plant (NPP) in March 2011 affected not only the terrestrial environment of Fukushima prefecture and the surrounding area, but also the marine area facing the NPP. Our present study is focused on the concentrations of radionuclides in agricultural products of Fukushima and sea-foods collected off Fukushima after the accident. The regulation value for radiocesium in vegetables, meat and fish was revised from 500 Bq/kg-wet to 100 Bq/kg-wet on 1 April 2012. The overall activity of radiocesium in these products was found to be within the limit of tolerance in respect to Japanese and also international regulations, but there is still radiocesium found at activities greater than this level in edible wild plants, wild mushrooms and game such as boar meat. Although the activities of radionuclides exceeding the regulatory limits were not detected in marine products collected off Fukushima after April 2015, the commercial marine fishery has not received approval in the affected areas except for certain species. We learned from the Fukushima accident that long-term kinetic studies of radionuclides in terrestrial and marine environments is extremely important for prevention of internal contamination, since contamination with radionuclides occurs via the food chain in the environment. (authors)

  17. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 3, Appendix A, Draft standard operating procedures and elements: Sampling and Analysis Plan (SAP): Phase 1, Task 4, Field Investigation, Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  18. Sensitive Multi-Species Emissions Monitoring: Infrared Laser-Based Detection of Trace-Level Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Steill, Jeffrey D. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Huang, Haifeng [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Hoops, Alexandra A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Patterson, Brian D. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Birtola, Salvatore R. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Jaska, Mark [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Strecker, Kevin E. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Chandler, David W. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Bisson, Soott [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2014-09-01

    This report summarizes our development of spectroscopic chemical analysis techniques and spectral modeling for trace-gas measurements of highly-regulated low-concentration species present in flue gas emissions from utility coal boilers such as HCl under conditions of high humidity. Detailed spectral modeling of the spectroscopy of HCl and other important combustion and atmospheric species such as H 2 O, CO 2 , N 2 O, NO 2 , SO 2 , and CH 4 demonstrates that IR-laser spectroscopy is a sensitive multi-component analysis strategy. Experimental measurements from techniques based on IR laser spectroscopy are presented that demonstrate sub-ppm sensitivity levels to these species. Photoacoustic infrared spectroscopy is used to detect and quantify HCl at ppm levels with extremely high signal-to-noise even under conditions of high relative humidity. Additionally, cavity ring-down IR spectroscopy is used to achieve an extremely high sensitivity to combustion trace gases in this spectral region; ppm level CH 4 is one demonstrated example. The importance of spectral resolution in the sensitivity of a trace-gas measurement is examined by spectral modeling in the mid- and near-IR, and efforts to improve measurement resolution through novel instrument development are described. While previous project reports focused on benefits and complexities of the dual-etalon cavity ring-down infrared spectrometer, here details on steps taken to implement this unique and potentially revolutionary instrument are described. This report also illustrates and critiques the general strategy of IR- laser photodetection of trace gases leading to the conclusion that mid-IR laser spectroscopy techniques provide a promising basis for further instrument development and implementation that will enable cost-effective sensitive detection of multiple key contaminant species simultaneously.

  19. A Portable Smart-Phone Readout Device for the Detection of Mercury Contamination Based on an Aptamer-Assay Nanosensor

    Directory of Open Access Journals (Sweden)

    Wei Xiao

    2016-11-01

    Full Text Available The detection of environmental mercury (Hg contamination requires complex and expensive instruments and professional technicians. We present a simple, sensitive, and portable Hg2+ detection system based on a smartphone and colorimetric aptamer nanosensor. A smartphone equipped with a light meter app was used to detect, record, and process signals from a smartphone-based microwell reader (MR S-phone, which is composed of a simple light source and a miniaturized assay platform. The colorimetric readout of the aptamer nanosensor is based on a specific interaction between the selected aptamer and Hg2+, which leads to a color change in the reaction solution due to an aggregation of gold nanoparticles (AuNPs. The MR S-phone-based AuNPs-aptamer colorimetric sensor system could reliably detect Hg2+ in both tap water and Pearl River water samples and produced a linear colorimetric readout of Hg2+ concentration in the range of 1 ng/mL–32 ng/mL with a correlation of 0.991, and a limit of detection (LOD of 0.28 ng/mL for Hg2+. The detection could be quickly completed in only 20 min. Our novel mercury detection assay is simple, rapid, and sensitive, and it provides new strategies for the on-site detection of mercury contamination in any environment.

  20. A Portable Smart-Phone Readout Device for the Detection of Mercury Contamination Based on an Aptamer-Assay Nanosensor.

    Science.gov (United States)

    Xiao, Wei; Xiao, Meng; Fu, Qiangqiang; Yu, Shiting; Shen, Haicong; Bian, Hongfen; Tang, Yong

    2016-11-08

    The detection of environmental mercury (Hg) contamination requires complex and expensive instruments and professional technicians. We present a simple, sensitive, and portable Hg 2+ detection system based on a smartphone and colorimetric aptamer nanosensor. A smartphone equipped with a light meter app was used to detect, record, and process signals from a smartphone-based microwell reader (MR S-phone), which is composed of a simple light source and a miniaturized assay platform. The colorimetric readout of the aptamer nanosensor is based on a specific interaction between the selected aptamer and Hg 2+ , which leads to a color change in the reaction solution due to an aggregation of gold nanoparticles (AuNPs). The MR S-phone-based AuNPs-aptamer colorimetric sensor system could reliably detect Hg 2+ in both tap water and Pearl River water samples and produced a linear colorimetric readout of Hg 2+ concentration in the range of 1 ng/mL-32 ng/mL with a correlation of 0.991, and a limit of detection (LOD) of 0.28 ng/mL for Hg 2+ . The detection could be quickly completed in only 20 min. Our novel mercury detection assay is simple, rapid, and sensitive, and it provides new strategies for the on-site detection of mercury contamination in any environment.

  1. Uncertainty quantification and experimental design based on unsupervised machine learning identification of contaminant sources and groundwater types using hydrogeochemical data

    Science.gov (United States)

    Vesselinov, V. V.

    2017-12-01

    Identification of the original groundwater types present in geochemical mixtures observed in an aquifer is a challenging but very important task. Frequently, some of the groundwater types are related to different infiltration and/or contamination sources associated with various geochemical signatures and origins. The characterization of groundwater mixing processes typically requires solving complex inverse models representing groundwater flow and geochemical transport in the aquifer, where the inverse analysis accounts for available site data. Usually, the model is calibrated against the available data characterizing the spatial and temporal distribution of the observed geochemical species. Numerous geochemical constituents and processes may need to be simulated in these models which further complicates the analyses. As a result, these types of model analyses are typically extremely challenging. Here, we demonstrate a new contaminant source identification approach that performs decomposition of the observation mixtures based on Nonnegative Matrix Factorization (NMF) method for Blind Source Separation (BSS), coupled with a custom semi-supervised clustering algorithm. Our methodology, called NMFk, is capable of identifying (a) the number of groundwater types and (b) the original geochemical concentration of the contaminant sources from measured geochemical mixtures with unknown mixing ratios without any additional site information. We also demonstrate how NMFk can be extended to perform uncertainty quantification and experimental design related to real-world site characterization. The NMFk algorithm works with geochemical data represented in the form of concentrations, ratios (of two constituents; for example, isotope ratios), and delta notations (standard normalized stable isotope ratios). The NMFk algorithm has been extensively tested on synthetic datasets; NMFk analyses have been actively performed on real-world data collected at the Los Alamos National

  2. Affinity extraction of emerging contaminants from water based on bovine serum albumin as a binding agent.

    Science.gov (United States)

    Papastavros, Efthimia; Remmers, Rachael A; Snow, Daniel D; Cassada, David A; Hage, David S

    2018-03-01

    Affinity sorbents using bovine serum albumin as a binding agent were developed and tested for the extraction of environmental contaminants from water. Computer simulations based on a countercurrent distribution model were also used to study the behavior of these sorbents. Several model drugs, pesticides, and hormones of interest as emerging contaminants were considered in this work, with carbamazepine being used as a representative analyte when coupling the albumin column on-line with liquid chromatography and tandem mass spectrometry. The albumin column was found to be capable of extracting carbamazepine from aqueous solutions that contained trace levels of this analyte. Further studies of the bovine serum albumin sorbent indicated that it had higher retention under aqueous conditions than a traditional C 18 support for most of the tested emerging contaminants. Potential advantages of using these protein-based sorbents included the low cost of bovine serum albumin and its ability to bind to a relatively wide range of drugs and related compounds. It was also shown how simulations could be used to describe the elution behavior of the model compounds on the bovine serum albumin sorbents as an aid in optimizing the retention and selectivity of these supports for use with liquid chromatography or methods such as liquid chromatography with tandem mass spectrometry. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. (Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

  4. Evaluation of microcystin contamination in blue-green algal dietary supplements using a protein phosphatase inhibition-based test kit.

    Science.gov (United States)

    Marsan, David W; Conrad, Stephen M; Stutts, Whitney L; Parker, Christine H; Deeds, Jonathan R

    2018-03-01

    The cyanobacterium Aphanizomenon flos-aquae (AFA), from Upper-Klamath Lake, Oregon, are used to produce blue-green algal (BGA) dietary supplements. The periodic co-occurrence of hepatotoxin-producing contaminant species prompted the Oregon Health Division to establish a limit of 1 μg/g microcystin (MC) for products sold in Oregon in 1997. At the federal level, the current good manufacturing practice (CGMP) regulations for dietary supplements require manufacturers establish a specification, and test, for limits on contaminants that may adulterate finished products. Despite this, several previous international surveys reported MC in BGA supplements in excess of 1 μg/g. The objectives of this study were (1) identify a reliable, easy to use test kit for the detection of MC in dried BGA materials and (2) use this kit to assess the occurrence of MC contamination in AFA-BGA dietary supplements in the U.S. A commercial protein phosphatase inhibition assay (PPIA), based on the enzyme PP2A, was found to have acceptable relative enzyme inhibition and accuracy for the majority of MC variants tested, including those most commonly identified in commercial samples, making the kit fit for purpose. Using the PPIA kit, 51% (26 of 51) distinct AFA-BGA products had MC ≥0.25 μg/g (the detection limit of the kit), 10 products had MC concentrations between 0.5 and 1.0 μg/g, and 4 products exceeded the limit (1.1-2.8 μg/g). LC-MS/MS confirmed PPIA results ≥0.5 μg/g and determined that MC-LA and MC-LR were the main congeners present. PPIA is a reliable method for the detection of MC contamination in dried BGA dietary supplements produced in the U.S. While the majority of AFA-BGA products contained ≥0.25 μg/g MC, most were at or below 1.0 μg/g, suggesting that manufacturers have adopted this level as a specification in these products; however, variability in recommended serving sizes prevented further analysis of consumer exposure based on the concentrations of MC

  5. Evaluation of microcystin contamination in blue-green algal dietary supplements using a protein phosphatase inhibition-based test kit

    Directory of Open Access Journals (Sweden)

    David W. Marsan

    2018-03-01

    Full Text Available The cyanobacterium Aphanizomenon flos-aquae (AFA, from Upper-Klamath Lake, Oregon, are used to produce blue-green algal (BGA dietary supplements. The periodic co-occurrence of hepatotoxin-producing contaminant species prompted the Oregon Health Division to establish a limit of 1 μg/g microcystin (MC for products sold in Oregon in 1997. At the federal level, the current good manufacturing practice (CGMP regulations for dietary supplements require manufacturers establish a specification, and test, for limits on contaminants that may adulterate finished products. Despite this, several previous international surveys reported MC in BGA supplements in excess of 1 μg/g. The objectives of this study were (1 identify a reliable, easy to use test kit for the detection of MC in dried BGA materials and (2 use this kit to assess the occurrence of MC contamination in AFA-BGA dietary supplements in the U.S. A commercial protein phosphatase inhibition assay (PPIA, based on the enzyme PP2A, was found to have acceptable relative enzyme inhibition and accuracy for the majority of MC variants tested, including those most commonly identified in commercial samples, making the kit fit for purpose. Using the PPIA kit, 51% (26 of 51 distinct AFA-BGA products had MC ≥0.25 μg/g (the detection limit of the kit, 10 products had MC concentrations between 0.5 and 1.0 μg/g, and 4 products exceeded the limit (1.1–2.8 μg/g. LC-MS/MS confirmed PPIA results ≥0.5 μg/g and determined that MC-LA and MC-LR were the main congeners present. PPIA is a reliable method for the detection of MC contamination in dried BGA dietary supplements produced in the U.S. While the majority of AFA-BGA products contained ≥0.25 μg/g MC, most were at or below 1.0 μg/g, suggesting that manufacturers have adopted this level as a specification in these products; however, variability in recommended serving sizes prevented further analysis of consumer exposure based on the concentrations of MC

  6. Locating the Source of Atmospheric Contamination Based on Data From the Kori Field Tracer Experiment

    Directory of Open Access Journals (Sweden)

    Piotr Kopka

    2015-01-01

    Full Text Available Accidental releases of hazardous material into the atmosphere pose high risks to human health and the environment. Thus it would be valuable to develop an emergency reaction system which can recognize the probable location of the source based only on concentrations of the released substance as reported by a network of sensors. We apply a methodology combining Bayesian inference with Sequential Monte Carlo (SMC methods to the problem of locating the source of an atmospheric contaminant. The input data for this algorithm are the concentrations of a given substance gathered continuously in time. We employ this algorithm to locating a contamination source using data from a field tracer experiment covering the Kori nuclear site and conducted in May 2001. We use the second-order Closure Integrated PUFF Model (SCIPUFF of atmospheric dispersion as the forward model to predict concentrations at the sensors' locations. We demonstrate that the source of continuous contamination may be successfully located even in the very complicated, hilly terrain surrounding the Kori nuclear site. (original abstract

  7. An approach to delineate the contaminated groundwater in landfill based on Electrical Resistivity Imaging Technique

    International Nuclear Information System (INIS)

    Nor Dalila Desa; Lakam Mejus; Mohd Tadza Abdul Rahman; Kamarudin Samuding; Roslanzairi Mostapa; Mod Omar Hassan

    2010-01-01

    Full text: The occurrence of contaminated groundwater can often be recognized by a decrease in formation of resistivity values, since the latter is primarily dependent on the resistivity of the pore water. Landfills can be considered as one of major source of contamination that contributes to air, land and water pollution. Landfills are supposed to have a protective bottom layer (barrier layer) to prevent contaminants from getting into the groundwater that exist almost everywhere underground. However, if there is no layer or if it is cracked, water percolating through landfills produces leachate can make their way down into the groundwater system. In geophysical studies, the various properties of materials on earth are known as the anomaly of the Earth's sub surface. It is important to understand which physical properties are associated with, and effective for, a particular target and geophysical method. This paper reviews the needs of geophysical field for mapping subsurface geology and features occurance. Electrical Resistivity Imaging (ERI) technique has been chosen for it has become one of the promising methods in order to obtain preliminary information of subsurface variance materials based on their physical properties. (author)

  8. Gas Bubbles Investigation in Contaminated Water Using Optical Tomography Based on Independent Component Analysis Method

    Directory of Open Access Journals (Sweden)

    Mohd Taufiq Mohd Khairi

    2016-01-01

    Full Text Available This paper presents the results of concentration profiles for gas bubble flow in a vertical pipeline containing contaminated water using an optical tomography system. The concentration profiles for the bubble flow quantities are investigated under five different flows conditions, a single bubble, double bubbles, 25% of air opening, 50% of air opening, and 100% of air opening flow rates where a valve is used to control the gas flow in the vertical pipeline. The system is aided by the independent component analysis (ICA algorithm to reconstruct the concentration profiles of the liquid-gas flow. The behaviour of the gas bubbles was investigated in contaminated water in which the water sample was prepared by adding 25 mL of colour ingredients to 3 liters of pure water. The result shows that the application of ICA has enabled the system to detect the presence of gas bubbles in contaminated water. This information provides vital information on the flow inside the pipe and hence could be very significant in increasing the efficiency of the process industries.

  9. Radiobiological significance of radioactive contamination - summary assessment based on great number of measurements

    Energy Technology Data Exchange (ETDEWEB)

    Angelov, V [Civil Defence Administration, Sofia (Bulgaria); Bonchev, Ts; Mavrodiev, V; Kyrdzhilov, N [Sofia Univ. (Bulgaria). Fizicheski Fakultet

    1996-12-31

    In order to facilitate quantitative and qualitative characterisation of radioactive contamination the authors introduce a relative estimate of radionuclide activity by setting as a reference the most abundant element -Co-60 in the case of the Kozloduy NPP. The ratio {eta}{sub i} of the mean annual permissible concentration in air for each radionuclide (RPC-92) to that of Co-60 is calculated. It is found that {eta}{sub i} has the same or close values for groups of radionuclides, e.g. {eta}{sub i} = 2.10{sup -4} for {sup 238} Pu, {sup 239} Pu, {sup 240} Pu, {sup 241} Am, {sup 244} Cm; {eta}{sub i} = 5 for {sup 89} Sr, {sup 91} Y; {sup 93} Nb, {sup 134} Cs, {sup 137} Cs; {eta}{sub i} = 50 for {sup 55} Fe, {sup 63} Ni, {sup 95} Zr, {sup 95} Nb, {sup 140} Ba, {sup 140} La. Then it is compared to the experimentally measured values of the same quantity {eta}{sub iexp}, derived from surface contamination data. The ratio {eta}{sub iexp}/{eta}{sub i} is plotted against log {eta}{sub i}. The resulting nomograms give graphic representation of the radiobiological significance of various radionuclide groups. Data from different locations at the Kozloduy NPP are presented. It is found that the alpha emitter contamination has highest values in the Unit 1 (WWER-440) control rooms after repair. The Unit 5 (WWER-1000) has lower alpha contamination compared to WWER-440 units. 1 ref., 5 figs., 1 tab.

  10. A survey of benthic sediment contaminants in reaches of the Columbia River Estuary based on channel sedimentation characteristics.

    Science.gov (United States)

    Counihan, Timothy D; Waite, Ian R; Nilsen, Elena B; Hardiman, Jill M; Elias, Edwin; Gelfenbaum, Guy; Zaugg, Steven D

    2014-06-15

    While previous studies have documented contaminants in fish, sediments, water, and wildlife, few specifics are known about the spatial distribution of contaminants in the Columbia River Estuary (CRE). Our study goal was to characterize sediment contaminant detections and concentrations in reaches of the CRE that were concurrently being sampled to assess contaminants in water, invertebrates, fish, and osprey (Pandion haliaetus) eggs. Our objectives were to develop a survey design based on sedimentation characteristics and then assess whether sediment grain size, total organic carbon (TOC), and contaminant concentrations and detections varied between areas with different sedimentation characteristics. We used a sediment transport model to predict sedimentation characteristics of three 16km river reaches in the CRE. We then compartmentalized the modeled change in bed mass after a two week simulation to define sampling strata with depositional, stable, or erosional conditions. We collected and analyzed bottom sediments to assess whether substrate composition, organic matter composition, and contaminant concentrations and detections varied among strata within and between the reaches. We observed differences in grain size fractions between strata within and between reaches. We found that the fine sediment fraction was positively correlated with TOC. Contaminant concentrations were statistically different between depositional vs. erosional strata for the industrial compounds, personal care products and polycyclic aromatic hydrocarbons class (Indus-PCP-PAH). We also observed significant differences between strata in the number of detections of Indus-PCP-PAH (depositional vs. erosional; stable vs. erosional) and for the flame retardants, polychlorinated biphenyls, and pesticides class (depositional vs. erosional, depositional vs. stable). When we estimated mean contaminant concentrations by reach, we observed higher contaminant concentrations in the furthest downstream

  11. A survey of benthic sediment contaminants in reaches of the Columbia River Estuary based on channel sedimentation characteristics

    Science.gov (United States)

    Counihan, Timothy D.; Waite, Ian R.; Nilsen, Elena B.; Hardiman, Jill M.; Elias, Edwin; Gelfenbaum, Guy; Zaugg, Steven D.

    2014-01-01

    While previous studies have documented contaminants in fish, sediments, water, and wildlife, few specifics are known about the spatial distribution of contaminants in the Columbia River Estuary (CRE). Our study goal was to characterize sediment contaminant detections and concentrations in reaches of the CRE that were concurrently being sampled to assess contaminants in water, invertebrates, fish, and osprey (Pandion haliaetus) eggs. Our objectives were to develop a survey design based on sedimentation characteristics and then assess whether sediment grain size, total organic carbon (TOC), and contaminant concentrations and detections varied between areas with different sedimentation characteristics. We used a sediment transport model to predict sedimentation characteristics of three 16 km river reaches in the CRE. We then compartmentalized the modeled change in bed mass after a two week simulation to define sampling strata with depositional, stable, or erosional conditions. We collected and analyzed bottom sediments to assess whether substrate composition, organic matter composition, and contaminant concentrations and detections varied among strata within and between the reaches. We observed differences in grain size fractions between strata within and between reaches. We found that the fine sediment fraction was positively correlated with TOC. Contaminant concentrations were statistically different between depositional vs. erosional strata for the industrial compounds, personal care products and polycyclic aromatic hydrocarbons class (Indus–PCP–PAH). We also observed significant differences between strata in the number of detections of Indus–PCP–PAH (depositional vs. erosional; stable vs. erosional) and for the flame retardants, polychlorinated biphenyls, and pesticides class (depositional vs. erosional, depositional vs. stable). When we estimated mean contaminant concentrations by reach, we observed higher contaminant concentrations in the furthest

  12. Feasibility of Using Phytoextraction to Remediate a Compost-Based Soil Contaminated with Cadmium.

    Science.gov (United States)

    Parisien, Michele A; Rutter, Allison; Zeeb, Barbara A

    2015-01-01

    Greenhouse and in-situ field experiments were used to determine the potential for phytoextraction to remediate soil contaminated with Cd from municipal solid waste (MSW) and sewage sludge (SS) compost application at a Peterborough (Canada) site. For the greenhouse experiment, one native (Chenopodium album) and three naturalized (Poa compressa, Brassica juncea, Helianthus annuus) plant species were planted in soil containing no detectable Cd (phytoextraction is therefore not feasible at this site. Though low Cd bioavailability has negative implications for Cd phytoextraction from MSW/SS compost-based soils, it may limit receptor exposure to Cd sufficiently to eliminate the potential for risk at this site.

  13. Effect of a base-catalyzed dechlorination process on the genotoxicity of PCB-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    DeMarini, D.M.; Houk, V.S.; Kornel, A.; Rogers, C.J.

    1992-01-01

    We evaluated the genotoxicity of dichloromethane (DCM) extracts of PCB-contaminated soil before and after the soil had been treated by a base-catalyzed dechlorination process, which involved heating a mixture of the soil, polyethylene glycol, and sodium hydroxide to 250-350 C. This dechlorination process reduced by over 99% the PCB concentration in the soil, which was initially 2,200 ppm. The DCM extracts of both control and treated soils were not mutagenic in strain TA100 of Salmonella, but they were mutagenic in strain TA98. The base-catalyzed dechlorination process reduced the mutagenic potency of the soil by approximately one-half. The DCM extracts of the soils before and after treatment were equally genotoxic in a prophage-induction assay in E. coli, which detects some chlorinated organic carcinogens that were not detected by the Salmonella mutagenicity assay. These results show that treatment of PCB-contaminated soil by this base-catalyzed dechlorination process did not increase the genotoxicity of the soil.

  14. Field—Based Supercritical Fluid Extraction of Hydrocarbons at Industrially Contaminated Sites

    Directory of Open Access Journals (Sweden)

    Peggy Rigou

    2002-01-01

    Full Text Available Examination of organic pollutants in groundwaters should also consider the source of the pollution, which is often a solid matrix such as soil, landfill waste, or sediment. This premise should be viewed alongside the growing trend towards field-based characterisation of contaminated sites for reasons of speed and cost. Field-based methods for the extraction of organic compounds from solid samples are generally cumbersome, time consuming, or inefficient. This paper describes the development of a field-based supercritical fluid extraction (SFE system for the recovery of organic contaminants (benzene, toluene, ethylbenzene, and xylene and polynuclear aromatic hydrocarbons from soils. A simple, compact, and robust SFE system has been constructed and was found to offer the same extraction efficiency as a well-established laboratory SFE system. Extraction optimisation was statistically evaluated using a factorial analysis procedure. Under optimised conditions, the device yielded recovery efficiencies of >70% with RSD values of 4% against the standard EPA Soxhlet method, compared with a mean recovery efficiency of 48% for a commercially available field-extraction kit. The device will next be evaluated with real samples prior to field deployment.

  15. Assessment of natural attenuation of ground-water contamination at sites FT03, LF13, and WP14/LF15, Dover Air Force Base, Delaware

    Science.gov (United States)

    Barbaro, Jeffrey R.

    2002-01-01

    source areas, and (6) determine whether intrinsic biodegradation is occurring at these sites.The water-quality data indicate that intrinsic biodegradation is occurring at all three sites. The strongest indication of intrinsic biodegradation is the detection of tetrachloroethene and trichloroethene breakdown products within and down-gradient of the source areas. The patterns of electron acceptors and metabolic by-products indicate that contaminant biodegradation has changed the prevailing geochemistry of the surficial aquifer, creating the strongly reducing conditions necessary for chlorinated solvent bio-degradation. Geochemical changes include depleted dissolved oxygen and elevated ferrous iron and methane levels relative to concentrations in uncontaminated zones of the surficial aquifer. At Fire Training Area Three and the Rubble Area Landfill sites, natural attenuation appears to be adequate for controlling the migration of the contaminant plumes. At the third site, the Liquid Waste Disposal and Receiver Station Landfills, the plume is larger and the uncertainty about the effectiveness of natural attenuation in reducing contaminant concentrations and controlling plume migration is greater. Ground-water data indicate, however, that U.S. Environmental Protection Agency maximum contaminant levels were not exceeded in any point-of-compliance wells located along the Base boundary.The information presented in this report led to the development of improved conceptual models for these sites, and to the recognition of four issues that are currently unclear and may need further study. These issues include delineating the areal and vertical extent of the contaminant plumes in greater detail, determining the extent of intrinsic biodegradation downgradient of the Liquid Waste Disposal and Receiver Station Landfills, deter-mining the fate of contaminants in the ground-water discharge areas, and determining the effect of temporal variability in source concentrations and ground-water

  16. BIOREGIS software platform based on GIS technology to support in-situ remediation of petroleum contaminated sites. Case study: razvad - dambovita county, Romania

    Energy Technology Data Exchange (ETDEWEB)

    Anicai, Ovidiu [Institute for Computers - ITC SA, Bucharest (Romania); Anicai, Liana [PSV COMPANY SA, Direction of Research, Bucharest (Romania)

    2011-12-15

    With a need for the management of petroleum contaminated sites on Romanian territory, an experimental software platform involving ESRI-ArcGIS technologies (BIOREGIS) is presented in this study. The BIOREGIS platform is aimed to: (i) Build the structure of relational, standardized databases to store spatial and textual characteristic information on polluted sites for further risk analysis and planning of remediation actions, (ii) improve the pollution risk assessment methodology for Romanian petroleum contaminated sites and its informatics implementation, and (iii) develop and operate the software platform for pollution risk based management involving GIS/remote sensing technologies and remediation activities. The operation of BIOREGIS has been tested for a pilot contaminated area situated at Razvad - Dambovita County, which has been subjected to in situ remediation procedures involving both bioremediation and electrokinetic processes. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Evaluation of targeted and untargeted effects-based monitoring tools to assess impacts of contaminants of emerging concern on fish in the South Platte River, CO

    Science.gov (United States)

    Rivers in the arid Western United States face increasing influences from anthropogenic contaminants due to population growth, urbanization, and drought. To better understand and more effectively track the impacts of these contaminants, biologically-based monitoring tools are incr...

  18. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    An environmental investigation of ground water conditions has been undertaken at Wright-Patterson Air Force Base (WPAFB), Ohio to obtain data to assist in the evaluation of a potential removal action to prevent, to the extent practicable, migration of the contaminated ground water across Base boundaries. Field investigations were limited to the central section of the southwestern boundary of Area C and the Springfield Pike boundary of Area B. Further, the study was limited to a maximum depth of 150 feet below grade. Three primary activities of the field investigation were: (1) installation of 22 monitoring wells, (2) collection and analysis of ground water from 71 locations, (3) measurement of ground water elevations at 69 locations. Volatile organic compounds including trichloroethylene, perchloroethylene, and/or vinyl chloride were detected in concentrations exceeding Maximum Contaminant Levels (MCL) at three locations within the Area C investigation area. Ground water at the Springfield Pike boundary of Area B occurs in two primary units, separated by a thicker-than-expected clay layers. One well within Area B was determined to exceed the MCL for trichloroethylene.

  19. A system for the rapid detection of bacterial contamination in cell-based therapeutica

    Science.gov (United States)

    Bolwien, Carsten; Erhardt, Christian; Sulz, Gerd; Thielecke, Hagen; Johann, Robert; Pudlas, Marieke; Mertsching, Heike; Koch, Steffen

    2010-02-01

    Monitoring the sterility of cell or tissue cultures is of major concern, particularly in the fields of regenerative medicine and tissue engineering when implanting cells into the human body. Our sterility-control system is based on a Raman micro-spectrometer and is able to perform fast sterility testing on microliters of liquid samples. In conventional sterility control, samples are incubated for weeks to proliferate the contaminants to concentrations above the detection limit of conventional analysis. By contrast, our system filters particles from the liquid sample. The filter chip fabricated in microsystem technology comprises a silicon nitride membrane with millions of sub-micrometer holes to retain particles of critical sizes and is embedded in a microfluidic cell specially suited for concomitant microscopic observation. After filtration, identification is carried out on the single particle level: image processing detects possible contaminants and prepares them for Raman spectroscopic analysis. A custom-built Raman-spectrometer-attachment coupled to the commercial microscope uses 532nm or 785nm Raman excitation and records spectra up to 3400cm-1. In the final step, the recorded spectrum of a single particle is compared to an extensive library of GMP-relevant organisms, and classification is carried out based on a support vector machine.

  20. The potential of compost-based biobarriers for Cr(VI) removal from contaminated groundwater: Column test

    International Nuclear Information System (INIS)

    Boni, Maria Rosaria; Sbaffoni, Silvia

    2009-01-01

    This paper presents the results of a column reactor test, aiming at evaluating the performance of a biological permeable barrier made of low-cost waste materials, for Cr(VI) removal from contaminated groundwater. A 1:1 by volume mixture of green compost and siliceous gravel was tested as reactive medium in the experimental activity. A 10 mg/l Cr(VI) contaminated solution was used and the residual Cr(VI) concentration along the column height and in the outlet was determined in the water samples collected daily. Also pH, redox potential and COD were analyzed. At the end of the test, the reactive medium was characterized in terms of Cr(VI) and total chromium. The Cr(VI) removal efficiency was higher than 99% during the entire experimental activity. The influence of the biological activity on Cr(VI) removal efficiency was evaluated by varying the organic carbon and nitrogen dosages in the contaminated solution fed to the system; a removal decrease was observed when the organic carbon was not enough to sustain the microbial metabolism. The Cr(VI) removal was strictly linked to the biological activity of the native biomass of compost. No Cr(III) was detected in the outlet: the Cr(III) produced was entrapped in the solid matrix. Two main processes involved were: adsorption on the organic-based matrix and reduction into Cr(III) mediated by the anaerobic microbial metabolism of the bacteria residing in green compost. Siliceous gravel was used as the structure matrix, since its contribution to the removal was almost negligible. Thanks to the proven efficiency and to the low-cost, the reactive medium used can represent a valid alternative to conventional approaches to chromium remediation.

  1. Physiologically-based toxicokinetic models help identifying the key factors affecting contaminant uptake during flood events

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Markus; Eichbaum, Kathrin [Department of Ecosystem Analysis, Institute for Environmental Research,ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Kammann, Ulrike [Thünen-Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Hudjetz, Sebastian [Department of Ecosystem Analysis, Institute for Environmental Research,ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Cofalla, Catrina [Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Buchinger, Sebastian; Reifferscheid, Georg [Federal Institute of Hydrology (BFG), Department G3: Biochemistry, Ecotoxicology, Am Mainzer Tor 1, 56068 Koblenz (Germany); Schüttrumpf, Holger [Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Preuss, Thomas [Department of Environmental Biology and Chemodynamics, Institute for Environmental Research,ABBt- Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); and others

    2014-07-01

    Highlights: • A PBTK model for trout was coupled with a sediment equilibrium partitioning model. • The influence of physical exercise on pollutant uptake was studies using the model. • Physical exercise during flood events can increase the level of biliary metabolites. • Cardiac output and effective respiratory volume were identified as relevant factors. • These confounding factors need to be considered also for bioconcentration studies. - Abstract: As a consequence of global climate change, we will be likely facing an increasing frequency and intensity of flood events. Thus, the ecotoxicological relevance of sediment re-suspension is of growing concern. It is vital to understand contaminant uptake from suspended sediments and relate it to effects in aquatic biota. Here we report on a computational study that utilizes a physiologically based toxicokinetic model to predict uptake, metabolism and excretion of sediment-borne pyrene in rainbow trout (Oncorhynchus mykiss). To this end, data from two experimental studies were compared with the model predictions: (a) batch re-suspension experiments with constant concentration of suspended particulate matter at two different temperatures (12 and 24 °C), and (b) simulated flood events in an annular flume. The model predicted both the final concentrations and the kinetics of 1-hydroxypyrene secretion into the gall bladder of exposed rainbow trout well. We were able to show that exhaustive exercise during exposure in simulated flood events can lead to increased levels of biliary metabolites and identified cardiac output and effective respiratory volume as the two most important factors for contaminant uptake. The results of our study clearly demonstrate the relevance and the necessity to investigate uptake of contaminants from suspended sediments under realistic exposure scenarios.

  2. Physiologically-based toxicokinetic models help identifying the key factors affecting contaminant uptake during flood events

    International Nuclear Information System (INIS)

    Brinkmann, Markus; Eichbaum, Kathrin; Kammann, Ulrike; Hudjetz, Sebastian; Cofalla, Catrina; Buchinger, Sebastian; Reifferscheid, Georg; Schüttrumpf, Holger; Preuss, Thomas

    2014-01-01

    Highlights: • A PBTK model for trout was coupled with a sediment equilibrium partitioning model. • The influence of physical exercise on pollutant uptake was studies using the model. • Physical exercise during flood events can increase the level of biliary metabolites. • Cardiac output and effective respiratory volume were identified as relevant factors. • These confounding factors need to be considered also for bioconcentration studies. - Abstract: As a consequence of global climate change, we will be likely facing an increasing frequency and intensity of flood events. Thus, the ecotoxicological relevance of sediment re-suspension is of growing concern. It is vital to understand contaminant uptake from suspended sediments and relate it to effects in aquatic biota. Here we report on a computational study that utilizes a physiologically based toxicokinetic model to predict uptake, metabolism and excretion of sediment-borne pyrene in rainbow trout (Oncorhynchus mykiss). To this end, data from two experimental studies were compared with the model predictions: (a) batch re-suspension experiments with constant concentration of suspended particulate matter at two different temperatures (12 and 24 °C), and (b) simulated flood events in an annular flume. The model predicted both the final concentrations and the kinetics of 1-hydroxypyrene secretion into the gall bladder of exposed rainbow trout well. We were able to show that exhaustive exercise during exposure in simulated flood events can lead to increased levels of biliary metabolites and identified cardiac output and effective respiratory volume as the two most important factors for contaminant uptake. The results of our study clearly demonstrate the relevance and the necessity to investigate uptake of contaminants from suspended sediments under realistic exposure scenarios

  3. Internal dose assessment of 238U contaminated soils based on in-vitro gastrointestinal protocol

    Science.gov (United States)

    Perama, Yasmin Mohd Idris; Rashid, Nur Shahidah Abdul; Majid, Amran Ab.; Siong, Khoo Kok

    2017-01-01

    Human exposure to natural radioactive uranium has been a great interest as more industrial rapidly growing contributes to radiation risks. The aim of this case study was to determine the internal dose in humans incorporated with ingestion of 238U contaminated soils. A gastrointestinal analogue test was employed to simulate the human digestive tract. In-vitro approach via German DIN 19738 model was developed in order to estimate the internal exposure of 238U due to ingestion of different types of soils. Synthetic gastrointestinal fluids assay via in-vitro method were produced to determine the concentration of 238U in various soils using ICP-MS. Based on the results, concentration of 238U in BRIS, laterite, peat and alluvium soils were in ranged between (0.0061 ± 0.0057 - 0.0488 ± 0.0148) ppm and (0.0005 ± 0.0004 - 0.0046 ± 0.0007) ppm in gastric and gastrointestinal phase respectively. Types of soil compositions and pH medium were some of the factors that influence mobilization and solubility of 238U contaminanted soil into the digestive juices that resembles human gastrointestinal tract. For the purpose of internal dose assessment, the committed efective dose from 238U intake in soils ranged between 1.237 × 10-11 - 9.8993 × 10-11 Sv y-1 for gastric phase and 1.0184 × 10-12 - 9.3294 × 10-12 Sv y-1 for gastric-intestinal phase. The internal dose measurements from this study were much lower from the recommended values. Hence, ingestion of 238U contaminated soils would not be expected to pose major health risk to humans.

  4. Response of gadolinium doped liquid scintillator to charged particles: measurement based on intrinsic U/Th contamination

    Science.gov (United States)

    Du, Q.; Lin, S. T.; He, H. T.; Liu, S. K.; Tang, C. J.; Wang, L.; Wong, H. T.; Xing, H. Y.; Yue, Q.; Zhu, J. J.

    2018-04-01

    A measurement is reported for the response to charged particles of a liquid scintillator named EJ-335 doped with 0.5% gadolinium by weight. This liquid scintillator was used as the detection medium in a neutron detector. The measurement is based on the in-situ α-particles from the intrinsic Uranium and Thorium contamination in the scintillator. The β–α and the α–α cascade decays from the U/Th decay chains were used to select α-particles. The contamination levels of U/Th were consequently measured to be (5.54±0.15)× 10‑11 g/g, (1.45±0.01)× 10‑10 g/g and (1.07±0.01)× 10‑11 g/g for 232Th, 238U and 235U, respectively, assuming secular equilibrium. The stopping power of α-particles in the liquid scintillator was simulated by the TRIM software. Then the Birks constant, kB, of the scintillator for α-particles was determined to be (7.28±0.23) mg/(cm2ṡMeV) by Birks' formulation. The response for protons is also presented assuming the kB constant is the same as for α-particles.

  5. Potential effect of diaper and cotton ball contamination on NMR- and LC/MS-based metabonomics studies of urine from newborn babies.

    Science.gov (United States)

    Goodpaster, Aaron M; Ramadas, Eshwar H; Kennedy, Michael A

    2011-02-01

    Nuclear magnetic resonance (NMR) and liquid chromatography/mass spectrometry (LC/MS) based metabonomics screening of urine has great potential for discovery of biomarkers for diseases that afflict newborn and preterm infants. However, urine collection from newborn infants presents a potential confounding problem due to the possibility that contaminants might leach from materials used for urine collection and influence statistical analysis of metabonomics data. In this manuscript, we have analyzed diaper and cotton ball contamination using synthetic urine to assess its potential to influence the outcome of NMR- and LC/MS-based metabonomics studies of human infant urine. Eight diaper brands were examined using the "diaper plus cotton ball" technique. Data were analyzed using conventional principal components analysis, as well as a statistical significance algorithm developed for, and applied to, NMR data. Results showed most diaper brands had distinct contaminant profiles that could potentially influence NMR- and LC/MS-based metabonomics studies. On the basis of this study, it is recommended that diaper and cotton ball brands be characterized using metabonomics methodologies prior to initiating a metabonomics study to ensure that contaminant profiles are minimal or manageable and that the same diaper and cotton ball brands be used throughout a study to minimize variation.

  6. Enhanced removal of lead from contaminated soil by polyol-based deep eutectic solvents and saponin

    Science.gov (United States)

    Mukhopadhyay, Soumyadeep; Mukherjee, Sumona; Hayyan, Adeeb; Hayyan, Maan; Hashim, Mohd Ali; Sen Gupta, Bhaskar

    2016-11-01

    Deep eutectic solvents (DESs) are a class of green solvents analogous to ionic liquids, but less costly and easier to prepare. The objective of this study is to remove lead (Pb) from a contaminated soil by using polyol based DESs mixed with a natural surfactant saponin for the first time. The DESs used in this study were prepared by mixing a quaternary ammonium salt choline chloride with polyols e.g. glycerol and ethylene glycol. A natural surfactant saponin obtained from soapnut fruit pericarp, was mixed with DESs to boost their efficiency. The DESs on their own did not perform satisfactory due to higher pH; however, they improved the performance of soapnut by up to 100%. Pb removal from contaminated soil using mixture of 40% DES-Gly and 1% saponin and mixture of 10% DES-Gly and 2% saponin were above 72% XRD and SEM studies did not detect any major corrosion in the soil texture. The environmental friendliness of both DESs and saponin and their affordable costs merit thorough investigation of their potential as soil washing agents.

  7. Towards a more appropriate water based extraction for the assessment of organic contaminant availability

    International Nuclear Information System (INIS)

    Hickman, Zachary A.; Reid, Brian J.

    2005-01-01

    This study correlated extractabilities of 37 d aged phenanthrene residues in four dissimilar soils with the fraction that was available for earthworm (Lumbricus rubellus) accumulation and microorganism (Pseudomonas sp.) mineralisation. Extractability was determined using two established techniques, namely (1) a water based extraction using CO 2 equilibrated water and (2) an aqueous based hydroxypropyl-β-cyclodextrin (HPCD) extraction. Results showed no relationship between earthworm accumulation and phenanthrene extractability using either HPCD (r 2 =0.07; slope=-4.76; n=5) or the water based extraction (r 2 =0.31; slope=-5.34; n=5). Earthworm accumulation was overestimated by both techniques. In contrast, the fraction of phenanthrene extractable using both the HPCD technique and the water based extraction correlated strongly with microbial mineralisation. However, the slopes of these linear relationships were 0.48 (r 2 =0.96; n=10), and 0.99 (r 2 =0.88; n=10) for the water based extraction and HPCD, respectively. Thus, the HPCD extraction provided values that were numerically close to the mineralisation values, whilst the water based extraction values were approximately half the mineralisation values. It is submitted that HPCD extraction provided an appropriate method of assessing the fraction of contaminant available for microbial mineralisation in these dissimilar soils. - No significant difference was found between microbially mineralised phenanthrene and extractability using hydroxypropyl-β-cyclodextrin in four dissimilar soils; the water-only extraction removed half of this fraction

  8. Enhancing Lecture Presentations in Introductory Biology with Computer-Based Multimedia.

    Science.gov (United States)

    Fifield, Steve; Peifer, Rick

    1994-01-01

    Uses illustrations and text to discuss convenient ways to organize and present computer-based multimedia to students in lecture classes. Includes the following topics: (1) Effects of illustrations on learning; (2) Using computer-based illustrations in lecture; (3) MacPresents-Multimedia Presentation Software; (4) Advantages of computer-based…

  9. Modeling Adsorption Based Filters (Bio-remediation of Heavy Metal Contaminated Water)

    Science.gov (United States)

    McCarthy, Chris

    I will discuss kinetic models of adsorption, as well as models of filters based on those mechanisms. These mathematical models have been developed in support of our interdisciplinary lab group, which is centered at BMCC/CUNY (City University of New York). Our group conducts research into bio-remediation of heavy metal contaminated water via filtration. The filters are constructed out of biomass, such as spent tea leaves. The spent tea leaves are available in large quantities as a result of the industrial production of tea beverages. The heavy metals bond with the surfaces of the tea leaves (adsorption). The models involve differential equations, stochastic methods, and recursive functions. I will compare the models' predictions to data obtained from computer simulations and experimentally by our lab group. Funding: CUNY Collaborative Incentive Research Grant (Round 12); CUNY Research Scholars Program.

  10. Risk-based economic decision analysis of remediation options at a PCE-contaminated site

    DEFF Research Database (Denmark)

    Lemming, Gitte; Friis-Hansen, P.; Bjerg, Poul Løgstrup

    2010-01-01

    by the remediation activities. More attention is increasingly being given to these secondary environmental impacts when evaluating remediation options. This paper presents a methodology for an integrated economic decision analysis which combines assessments of remediation costs, health risk costs and potential...... at a downstream groundwater well. Potential environmental impacts on the local, regional and global scales due to the site remediation activities are evaluated using life cycle assessments (LCA). The potential impacts on health and environment are converted to monetary units using a simplified cost model. A case......Remediation methods for contaminated sites cover a wide range of technical solutions with different remedial efficiencies and costs. Additionally, they may vary in their secondary impacts on the environment i.e. the potential impacts generated due to emissions and resource use caused...

  11. Development of Triad approach based system for ecological risk assessment for contaminated areas of Kyrgyzstan

    Science.gov (United States)

    Kydralieva, Kamilia; Uzbekov, Beksultan; Khudaibergenova, Bermet; Terekhova, Vera; Jorobekova, Sharipa

    2014-05-01

    This research is aimed to develop a high-effective system of an ecological risk assessment and risk-based decision making for anthropogenic ecosystems, with particular focus on the soils of the Kyrgyz Republic. The study is focused on the integration of Triad data including chemical, biological and ecotoxicological soil markers to estimate the potential risk from soils of highly anthropized areas impacted by deposition of different pollutants from mining operation. We focus on technogenic areas of Kyrgyzstan, the former uranium-producing province. Triad-based ecological risk assessment for technogenic sites are not currently used in Kyrgyzstan. However, the vitality of such research is self-evident. There are about 50 tailing dumps and more than 80 tips of radioactive waste which are formed as a result of uranium and complex ores (mercury, antimony, lead, cadmium and etc) mining around the unfavorable aforementioned places. According to the Mining Wastes' Tailings and Fills Rehabilitation Centre established in 1999 by a special Government's Resolution, one of the most ecologically dangerous uranium tailings resides in Kadzhi-Say. Although uranium processing is no longer practiced in Kadzhi-Say, a large number of open landfills and uranium ore storages still remain abandoned at the vicinity of this settlement. These neglected sites have enormous problems associated with soil erosion known as "technogenic deserts". The upper soil horizons are deprived of humus and vegetation, which favor the formation of low-buffer landscapes in the zones of maximum contamination. As a result, most of these areas are not re-cultivated and remain in critical environmental condition (Bykovchenko, et al., 2005; Tukhvatshin, 2005; Suranova, 2006). Triad data for assessing environmental risk and biological vulnerability at contaminated sites will be integrated. The following Triad-based parameters will be employed: 1) chemical soil analyses (revealing the presence of potentially dangerous

  12. Adaptive sampling based on the cumulative distribution function of order statistics to delineate heavy-metal contaminated soils using kriging

    International Nuclear Information System (INIS)

    Juang, K.-W.; Lee, D.-Y.; Teng, Y.-L.

    2005-01-01

    Correctly classifying 'contaminated' areas in soils, based on the threshold for a contaminated site, is important for determining effective clean-up actions. Pollutant mapping by means of kriging is increasingly being used for the delineation of contaminated soils. However, those areas where the kriged pollutant concentrations are close to the threshold have a high possibility for being misclassified. In order to reduce the misclassification due to the over- or under-estimation from kriging, an adaptive sampling using the cumulative distribution function of order statistics (CDFOS) was developed to draw additional samples for delineating contaminated soils, while kriging. A heavy-metal contaminated site in Hsinchu, Taiwan was used to illustrate this approach. The results showed that compared with random sampling, adaptive sampling using CDFOS reduced the kriging estimation errors and misclassification rates, and thus would appear to be a better choice than random sampling, as additional sampling is required for delineating the 'contaminated' areas. - A sampling approach was derived for drawing additional samples while kriging

  13. Radiological assessment of past, present and potential sources to environmental contamination in the Southern Urals and strategies for remedial measures (SUCON)

    DEFF Research Database (Denmark)

    Aarkrog, A.; Simmonds, J.; Strand, P.

    2001-01-01

    This report summarises work done on the SUCON Project during 1996-1999 (European Commission Contract No. FI4C-CT95-0001). The project has focused on three major objectives: 1) An assessment of the radiological consequences of the contamination of theSouth Urals and the Ob river system from...

  14. Assessing the impact of groundwater contamination on stream water quality by multiple approaches at the groundwater-surface water interface (Invited Presentation)

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup; Rønde, Vinni Kampman; Balbarini, Nicola

    Contaminants such as chlorinated solvents and pesticides, as well as new classes of compounds or emerging micropollutants are extensively produced, utilized and then discarded in society and subsequently released to streams from multiple point and diffuse sources. Sustainable management of water...

  15. Microlith-based Structured Sorbent for Carbon Dioxide, Humidity, and Trace Contaminant Control in Manned Space Habitats

    Science.gov (United States)

    Junaedi, Christian; Roychoudhury, SUbir; Howard, David F.; Perry, Jay L.; Knox, James C.

    2011-01-01

    To support continued manned space exploration, the development of atmosphere revitalization systems that are lightweight, compact, durable, and power efficient is a key challenge. The systems should be adaptable for use in a variety of habitats and should offer operational functionality to either expel removed constituents or capture them for closedloop recovery. As mission durations increase and exploration goals reach beyond low earth orbit, the need for regenerable adsorption processes for continuous removal of CO2 and trace contaminants from cabin air becomes critical. Precision Combustion, Inc. (PCI) and NASA Marshall (MSFC) have been developing an Engineered Structured Sorbents (ESS) approach based on PCI s patented Microlith technology to meet the requirements of future, extended human spaceflight explorations. This technology offers the inherent performance and safety attributes of zeolite and other sorbents with greater structural integrity, regenerability, and process control, thereby providing potential durability and efficiency improvements over current state-of-the-art systems. The major advantages of the ESS explored in this study are realized through the use of metal substrates to provide structural integrity (i.e., less partition of sorbents) and enhanced thermal control during the sorption process. The Microlith technology also offers a unique internal resistive heating capability that shows potential for short regeneration time and reduced power requirement compared to conventional systems. This paper presents the design, development, and performance results of the integrated adsorber modules for removing CO2, water vapor, and trace chemical contaminants. A related effort that utilizes the adsorber modules for sorption of toxic industrial chemicals is also discussed. Finally, the development of a 4-person two-leg ESS system for continuous CO2 removal is also presented.

  16. Bench-scale studies of reactor-based treatment of fuel-contaminated soils

    International Nuclear Information System (INIS)

    Truax, D.D.; Britto, R.; Sherrard, J.H.

    1995-01-01

    Biological treatment of hazardous wastes from accidental spills or underground storage tank leaks has generated interest in bioremediation as a natural, economical mechanism for site decontamination. Because of drawbacks of batch systems, and the successful use of continuous flow treatment of wastewater for several decades, it was felt that continuous treatment of such soils would be a feasible alternative treatment technique. Therefore, bench-scale bioreactor treatability studies were conducted and used contaminated soil made in the laboratory using No. 2 diesel fuel and sand. Contamination levels studied were from 1,335--6,675 mg (TPH) as derived from No. 2 fuel oil per kg sand. Variation in mean cell age was obtained between reactors, with sufficient nutrients and oxygen made available to ensure the fuel oil organics were the only limit to microbial growth. A theoretical biokinetic model was formulated based on Monod's theory of limiting substrate and continuous cultures. Biokinetic constants and removal efficiencies were evaluated. The off-gases, CO 2 , and volatile hydrocarbons were monitored for mass balance analysis of the process. The solids retention times for evaluating final TPH concentration of 100 mg/kg were also calculated. Removal efficiencies of up to 91% were attained at a loading of 1,335 mg TPH/kg wet sand, operated at a biological solid retention time (BSRT) of 60 days. Experiments also showed that TPH desorption and volatilization were not rate-limiting in the overall removal process. Sand-to-moisture ratios in excess of 3:1 were also shown to retard TPH removal rates very little. However, biokinetic constants were found to vary over a range of values. This was particularly true at varying diesel loading levels. Nevertheless, significant removal efficiency (up to 86%) was noted at the highest loading level tested, 6,675 mg TPH/kg wet sand

  17. Monte Carlo N-particle simulation of neutron-based sterilisation of anthrax contamination.

    Science.gov (United States)

    Liu, B; Xu, J; Liu, T; Ouyang, X

    2012-10-01

    To simulate the neutron-based sterilisation of anthrax contamination by Monte Carlo N-particle (MCNP) 4C code. Neutrons are elementary particles that have no charge. They are 20 times more effective than electrons or γ-rays in killing anthrax spores on surfaces and inside closed containers. Neutrons emitted from a (252)Cf neutron source are in the 100 keV to 2 MeV energy range. A 2.5 MeV D-D neutron generator can create neutrons at up to 10(13) n s(-1) with current technology. All these enable an effective and low-cost method of killing anthrax spores. There is no effect on neutron energy deposition on the anthrax sample when using a reflector that is thicker than its saturation thickness. Among all three reflecting materials tested in the MCNP simulation, paraffin is the best because it has the thinnest saturation thickness and is easy to machine. The MCNP radiation dose and fluence simulation calculation also showed that the MCNP-simulated neutron fluence that is needed to kill the anthrax spores agrees with previous analytical estimations very well. The MCNP simulation indicates that a 10 min neutron irradiation from a 0.5 g (252)Cf neutron source or a 1 min neutron irradiation from a 2.5 MeV D-D neutron generator may kill all anthrax spores in a sample. This is a promising result because a 2.5 MeV D-D neutron generator output >10(13) n s(-1) should be attainable in the near future. This indicates that we could use a D-D neutron generator to sterilise anthrax contamination within several seconds.

  18. A laboratory based experimental study of mercury emission from contaminated soils in the River Idrijca catchment

    Directory of Open Access Journals (Sweden)

    D. Kocman

    2010-02-01

    Full Text Available Results obtained by a laboratory flux measurement system (LFMS focused on investigating the kinetics of the mercury emission flux (MEF from contaminated soils of the Idrija Hg-mine region, Slovenia are presented. Representative soil samples with respect to total Hg concentrations (4–417 μg g−1 and land cover (forest, meadow and alluvial soil alongside the River Idrijca were analysed to determine the variation in MEF versus distance from the source, regulating three major environmental parameters comprising soil temperature, soil moisture and solar radiation. MEFs ranged from less than 2 to 530 ng m−2 h−1, with the highest emissions from contaminated alluvial soils and soils near the mining district in the town of Idrija. A significant decrease of MEF was then observed with increasing distance from these sites. The results revealed a strong positive effect of all three parameters investigated on momentum MEF. The light-induced flux was shown to be independent of the soil temperature, while the soil aqueous phase seems to be responsible for recharging the pool of mercury in the soil available for both the light- and thermally-induced flux. The overall flux response to simulated environmental conditions depends greatly on the form of Hg in the soil. Higher activation energies are required for the overall process to occur in soils where insoluble cinnabar prevails compared to soils where more mobile Hg forms and forms available for transformation processes are dominant.

  19. The study of metal contamination in urban soils of Hong Kong using a GIS-based approach

    International Nuclear Information System (INIS)

    Li Xiangdong; Lee Siulan; Wong Szechung; Shi Wenzhong; Thornton, Iain

    2004-01-01

    The study of regional variations and the anthropogenic contamination by metals of soils is very important for environmental planning and monitoring in urban areas. An extensive survey was conducted in the highly urbanized Kowloon area (46.9 km 2 ) of Hong Kong, using a systematic sampling strategy with a sampling density of 3-5 composite soil samples (0-15 cm) per km 2 . Geochemical maps of 'total' metals (Cd, Cr, Cu, Ni, Pb and Zn) from strong acid extraction in the surface soils were produced based on geographical information system (GIS) technology. A significant spatial relationship was found for Ni, Cu, Pb and Zn in the soils using a GIS-based analysis, suggesting that these metal contaminants in the soils of the Kowloon area had common sources. Several hot-spot areas of metal contamination were identified from the composite metal geochemical map, mainly in the old industrial and residential areas. A further GIS analysis revealed that road junctions, major roads and industrial buildings were possible sources of heavy metals in the urban soils. The Pb isotope composition of the contaminated soils showed clear anthropogenic origins. - GIS can be used to identify soil contamination hot-spot areas and to assess potential pollutant sources in an urban community

  20. A Cercla-Based Decision Model to Support Remedy Selection for an Uncertain Volume of Contaminants at a DOE Facility

    Energy Technology Data Exchange (ETDEWEB)

    Christine E. Kerschus

    1999-03-31

    The Paducah Gaseous Diffusion Plant (PGDP) operated by the Department of Energy is challenged with selecting the appropriate remediation technology to cleanup contaminants at Waste Area Group (WAG) 6. This research utilizes value-focused thinking and multiattribute preference theory concepts to produce a decision analysis model designed to aid the decision makers in their selection process. The model is based on CERCLA's five primary balancing criteria, tailored specifically to WAG 6 and the contaminants of concern, utilizes expert opinion and the best available engineering, cost, and performance data, and accounts for uncertainty in contaminant volume. The model ranks 23 remediation technologies (trains) in their ability to achieve the CERCLA criteria at various contaminant volumes. A sensitivity analysis is performed to examine the effects of changes in expert opinion and uncertainty in volume. Further analysis reveals how volume uncertainty is expected to affect technology cost, time and ability to meet the CERCLA criteria. The model provides the decision makers with a CERCLA-based decision analysis methodology that is objective, traceable, and robust to support the WAG 6 Feasibility Study. In addition, the model can be adjusted to address other DOE contaminated sites.

  1. A Cercla-Based Decision Model to Support Remedy Selection for an Uncertain Volume of Contaminants at a DOE Facility

    International Nuclear Information System (INIS)

    Christine E. Kerschus

    1999-01-01

    The Paducah Gaseous Diffusion Plant (PGDP) operated by the Department of Energy is challenged with selecting the appropriate remediation technology to cleanup contaminants at Waste Area Group (WAG) 6. This research utilizes value-focused thinking and multiattribute preference theory concepts to produce a decision analysis model designed to aid the decision makers in their selection process. The model is based on CERCLA's five primary balancing criteria, tailored specifically to WAG 6 and the contaminants of concern, utilizes expert opinion and the best available engineering, cost, and performance data, and accounts for uncertainty in contaminant volume. The model ranks 23 remediation technologies (trains) in their ability to achieve the CERCLA criteria at various contaminant volumes. A sensitivity analysis is performed to examine the effects of changes in expert opinion and uncertainty in volume. Further analysis reveals how volume uncertainty is expected to affect technology cost, time and ability to meet the CERCLA criteria. The model provides the decision makers with a CERCLA-based decision analysis methodology that is objective, traceable, and robust to support the WAG 6 Feasibility Study. In addition, the model can be adjusted to address other DOE contaminated sites

  2. Data sheet based countermeasure evaluation for radioactively contaminated Nordic food-producing areas

    International Nuclear Information System (INIS)

    Andersson, K.G.; Roed, J.; Rantavaara, A.; Rosen, K.; Salbu, B.; Skipperud, L.

    2002-01-01

    A Nordic expert group has identified and critically evaluated the countermeasures that may potentially be implemented in connection with major nuclear accident situations contaminating Nordic food-producing areas. This paper demonstrates how the derived technical information can be applied by decision-makers to identify practicable and cost-effective means for mitigation of the impact of contamination. (au)

  3. Alginate-based polysaccharide beads for cationic contaminant sorption from water

    Science.gov (United States)

    Mei Li; Thomas Elder; Gisela Buschle-Diller

    2016-01-01

    Massive amounts of agricultural and industrial water worldwide are polluted by different types of contaminants that harm the environment and impact human health. Removing the contaminants from effluents by adsorbent materials made from abundant, inexpensive polysaccharides is a feasible approach to deal with this problem. In this research, alginate beads combined with...

  4. Data sheet based countermeasure evaluation for radioactively contaminated Nordic food-producing areas

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, K.G.; Roed, J. [Risoe National Lab., Roskilde (Denmark); Rantavaara, A. [STUK, Helsinki (Finland); Rosen, K. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden); Salbu, B.; Skipperud, L. [Agricultural Univ. of Norway, Aas (Norway)

    2002-04-01

    A Nordic expert group has identified and critically evaluated the countermeasures that may potentially be implemented in connection with major nuclear accident situations contaminating Nordic food-producing areas. This paper demonstrates how the derived technical information can be applied by decision-makers to identify practicable and cost-effective means for mitigation of the impact of contamination. (au)

  5. Contamination shield

    International Nuclear Information System (INIS)

    Bayer, W.; Pecornik, D.

    1982-01-01

    An acrylate resin is presented as contamination protection coating for components and instruments in nuclear facilities and for spent fuel transport containers. The resin is evaporated or sublimated at 130 0 C and can thus be removed easily from the protected component. The radioactive particles entrained during evaporation are retained by suitable filters. (TK) [de

  6. Cotton contamination

    CSIR Research Space (South Africa)

    Van der Sluijs, MHJ

    2018-05-01

    Full Text Available This review focusses on physical forms of contaminant including the presence, prevention and/or removal of foreign bodies, stickiness and seed-coat fragments rather than the type and quantity of chemical residues that might be present in cotton...

  7. Geophysics Based Contaminant Mass Discharge Quantification Downgradient of a Landfill and a Former Pharmaceutical Factory

    DEFF Research Database (Denmark)

    Balbarini, Nicola; Rønde, Vinni Kampman; Maurya, Pradip

    2018-01-01

    Contaminant mass discharge is a commonly applied tool to evaluate the environmental impact of contaminated sites on water resources. At large contaminated sites with heterogeneous sources, such as landfills, the number of wells available is often not sufficient, leading to a high uncertainty...... of mass discharge estimates. In this study, we tackle the uncertainty of the contaminant mass discharge due to low sampling densities by interpolating limited water‐sample data with the support of surface Direct Current resistivity and Induced Polarization geophysical data. The method relies on finding...... a conceptual link between the bulk conductivity imaged from geophysics and the contaminant concentrations. We investigate the link between: 1) imaged bulk and electrical water conductivity, 2) water conductivity and conservative ionic species, 3) water conductivity and redox‐sensitive species, 4) water...

  8. Multimedia risk-based soil cleanup at a gasoline-contaminated site using vapor extraction

    International Nuclear Information System (INIS)

    Mills, W.B.; Johnson, K.M.; Liu, S.; Loh, J.Y.; Lew, C.S.

    1996-01-01

    At a utility service center, gasoline from an underground storage tank had leaked into subsurface vadose zone soils for several years. To remediate the site, a soil vapor extraction (SVE) system was installed and operated. At the completion of the SVE operation, gasoline-containing residues in several confirmation soil borings exceeded agency-mandated cleanup levels. Rather than continue with SVE, a risk-based approach was developed to evaluate what levels of gasoline-containing residues could be left in the soil and still protect human health. The risk-based approach consisted of simulating the fate of chemical residues through the vadose zone and then into both the ground water and atmosphere. Receptor point concentrations were predicted, and health risks were assessed. The risk assessment concluded that ingestion of contaminated ground water and inhalation of air while showering were the largest potential contributors to risk, and that risks associated with inhalation of vapor-containing ambient air are small. However, all predicted risks are below the acceptable risk levels of 10 -6 individual cancer risk probability and 1.0 hazard index. Therefore, the lead agency accepted the recommendation that the site requires no further remediation. The service center continues normal operations today

  9. Equilibrium Strategy Based Recycling Facility Site Selection towards Mitigating Coal Gangue Contamination

    Directory of Open Access Journals (Sweden)

    Jiuping Xu

    2017-02-01

    Full Text Available Environmental pollution caused by coal gangue has been a significant challenge for sustainable development; thus, many coal gangue reduction approaches have been proposed in recent years. In particular, coal gangue facility (CGF construction has been considered as an efficient method for the control and recycling of coal gangue. Meanwhile, the identification and selection of suitable CGF sites is a fundamental task for the government. Therefore, based on the equilibrium strategy, a site selection approach under a fuzzy environment is developed to mitigate coal gangue contamination, which integrates a geographical information system (GIS technique and a bi-level model to identify candidate CGF sites and to select the most suitable one. In this situation, the GIS technique used to identify potential feasible sites is able to integrate a great deal of geographical data tofitwithpracticalcircumstances;thebi-levelmodelusedtoscreentheappropriatesitecanreasonably dealwiththeconflictsbetweenthelocalauthorityandthecolliery. Moreover,aKarush–Kuhn–Tucker (KKT condition-based approach is used to find an optimal solution, and a case study is given to demonstrate the effectiveness of the proposed method. The results across different scenarios show that appropriate site selection can achieve coal gangue reduction targets and that a suitable excess stack level can realize an environmental-economic equilibrium. Finally, some propositions and management recommendations are given.

  10. Optimization of the control of contamination at nuclear power plants

    International Nuclear Information System (INIS)

    Khan, T.A.; Baum, J.W.

    1988-05-01

    A methodology is described for the optimization of the actions taken to control contamination. It deals with many aspects of contamination, such as the monetary value assigned to a unit of radiation dose, the treatment of skin and extremity dose, and the inefficiencies introduced from working in a contaminated environemnt. The optimization method is illustrated with two case studies based on cleanup projects at nuclear power plants. Guidelines for the use of protective apparel, and for monitoring radiation and contamination at various levels of contamination are presented. The report concludes that additional research is required to quantify the effect of a contaminated environment on work efficiencies

  11. Accounting for nanometer-thick adventitious carbon contamination in X-ray absorption spectra of carbon-based materials.

    Science.gov (United States)

    Mangolini, Filippo; McClimon, J Brandon; Rose, Franck; Carpick, Robert W

    2014-12-16

    Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy is a powerful technique for characterizing the composition and bonding state of nanoscale materials and the top few nanometers of bulk and thin film specimens. When coupled with imaging methods like photoemission electron microscopy, it enables chemical imaging of materials with nanometer-scale lateral spatial resolution. However, analysis of NEXAFS spectra is often performed under the assumption of structural and compositional homogeneity within the nanometer-scale depth probed by this technique. This assumption can introduce large errors when analyzing the vast majority of solid surfaces due to the presence of complex surface and near-surface structures such as oxides and contamination layers. An analytical methodology is presented for removing the contribution of these nanoscale overlayers from NEXAFS spectra of two-layered systems to provide a corrected photoabsorption spectrum of the substrate. This method relies on the subtraction of the NEXAFS spectrum of the overlayer adsorbed on a reference surface from the spectrum of the two-layer system under investigation, where the thickness of the overlayer is independently determined by X-ray photoelectron spectroscopy (XPS). This approach is applied to NEXAFS data acquired for one of the most challenging cases: air-exposed hard carbon-based materials with adventitious carbon contamination from ambient exposure. The contribution of the adventitious carbon was removed from the as-acquired spectra of ultrananocrystalline diamond (UNCD) and hydrogenated amorphous carbon (a-C:H) to determine the intrinsic photoabsorption NEXAFS spectra of these materials. The method alters the calculated fraction of sp(2)-hybridized carbon from 5 to 20% and reveals that the adventitious contamination can be described as a layer containing carbon and oxygen ([O]/[C] = 0.11 ± 0.02) with a thickness of 0.6 ± 0.2 nm and a fraction of sp(2)-bonded carbon of 0.19 ± 0.03. This

  12. Characterization and remediation of a mixed waste-contaminated site at Kirtland Air Force Base, New Mexico

    International Nuclear Information System (INIS)

    Johnston, J.W.; Thacker, M.S.; DeWitt, C.B.

    1997-01-01

    In the area of environmental restoration, one of the most challenging problems is the task of remediating mixed waste-contaminated sites. This paper discusses a successful Interim Corrective Measure (ICM) performed at a mixed waste-contaminated site on Kirtland Air Force Base (AFB) in Albuquerque, New Mexico. The site, known as RW-68, Cratering Area and Radium Dump/Slag Piles, was used during the late 1940s and early 1950s for the destruction and incineration of captured World War II aircraft. It contained 19 slag piles totaling approximately 150 tons of slag, ash, refractory brick, and metal debris. The piles were contaminated with radium-226 and RCRA-characteristic levels of heavy metals. Therefore, the piles were considered mixed waste. To eliminate the threat to human health and the environment, an ICM of removal, segregation, stabilization, and disposal was conducted from October through December 1996. Approximately 120 cubic yards (cu yds) of mixed waste, 188 cu yds of low-level radioactive-contaminated soil, 1 cu yd of low-level radioactive-contaminated debris, 5 cu yds of RCRA-characteristic hazardous waste, and 45 tons of nonhazardous debris were stabilized and disposed of during the ICM. To render the RCRA metals and radionuclides insoluble, stabilization was performed on the mixed and RCRA-characteristic waste streams. All stabilized material was subjected to TCLP analysis to verify it no longer exhibited RCRA-characteristic properties. Radiological and geophysical surveys were conducted concurrently with site remediation activities. These surveys provided real-time documentation of site conditions during each phase of the ICM and confirmed successful cleanup of the site. The three radioactive waste streams, stabilized mixed waste, low-level radioactive-contaminated soil, and low-level radioactive-contaminated debris, were disposed of at the Envirocare low-level radioactive disposal facility

  13. Relationship between ecophysiological factors, growth and ochratoxin A contamination of dry-cured sausage based matrices.

    Science.gov (United States)

    Rodríguez, Alicia; Capela, Daniela; Medina, Ángel; Córdoba, Juan J; Magan, Naresh

    2015-02-02

    Dry-cured sausages are colonised by moulds during the ripening process. The temperature and the salt content (which affects water activity, aw) predispose the surface to colonisation by Penicillium species, including Penicillium nordicum and Penicillium verrucosum which can lead to contamination of the sausages with ochratoxin A (OTA). The objective of this work was to obtain scientific data on the impact that interaction between ionic water stress (aw; 0.97, 0.94, 0.90, 0.87 and 0.84) and temperature (30, 25, 20, 15 and 10°C) may have on lag phases prior to growth, growth and OTA production by some P. verrucosum and P. nordicum strains isolated from dry-cured meat products on a dry-cured sausage-based medium over a period of 12days. Although P. nordicum had shorter lag phases than P. verrucosum, the latter grew faster than P. nordicum in most conditions tested. For both species, there was no growth and OTA production at 0.84 aw at all the temperatures tested. The fungi were more tolerant at moderate ionic aw conditions (0.94 and 0.90) and 20 and 25°C. In contrast, the patterns of production of OTA were very different from those for growth. Different OTA production profiles between the two OTA-producing species were found. While P. nordicum began producing OTA in most of the conditions tested by day 6, P. verrucosum only produced the toxin in these conditions when the temperature and aw were >10°C and >0.90, respectively. However, the P. verrucosum strain produced much higher concentrations of OTA than the P. nordicum strain in all conditions. We developed contour maps of the optimum and marginal aw×temperature conditions for growth/OTA production on dry-cured sausage-based medium for the first time. This suggests that these interacting conditions during the early phases of production must be effectively controlled as these favour growth of the toxigenic Penicillia. Knowledge on the ecophysiology of these two important Penicillium species on these matrices

  14. Comparison of Phytoscreening and Direct-Push- Based Site Investigation at a Rural Megasite Contaminated with Chlorinated Ethenes

    DEFF Research Database (Denmark)

    Rein, Arno; Holm, Olaf; Trapp, Stefan

    2015-01-01

    areas in particular. Here we compare two site screening techniques that can be applied quickly at relatively low cost, namely Direct Push (DP)-based groundwater sampling and tree core sampling. The effectiveness of both methods is compared for a rural megasite contaminated with chlorinated hydrocarbons...

  15. Scientific bases for decision making after a radioactive contamination of an urban environment: The design of the repository

    International Nuclear Information System (INIS)

    Tranjan Filho, A.

    2000-01-01

    The paper to be presented will discuss, specifically, technical aspects of the Repository design in case of urban contamination. It will be emphasise what to decide, how to decide and what are the difficulties to decide. The case of Goiania it will be used as demonstration, in some cases, as a practical example. (author)

  16. Assessments of risk indices and decision-making support within risk based land management and sustainable rehabilitation of radioactive contaminated territories

    International Nuclear Information System (INIS)

    Yatsalo, B.; Didenko, V.; Golikov, V.

    2002-01-01

    Description of the applied Geoinformation Decision-Support System PRANA for risk based land management and rehabilitation of territories of Bryansk region (Russia), subjected to radioactive contamination as a result of the Chernobyl accident, is presented. The main blocks of PRANA DSS, including electronic maps, databases and models are described. Implementation of vector land use map with corresponding integration of different models allows integrating both local and regional level of analysis and practical implementation (from each field and settlement up to farm and district and regional levels). Some examples of model assessments (map of countermeasures and doses) are presented

  17. Application Of The SPV-based Surface Lifetime Technique To In-Line Monitoring Of Surface Cu Contamination

    Science.gov (United States)

    D'Amico, John; Savtchouk, Alexandre; Wilson, Matthew; Kim, Chul Hong; Yoo, Hyung Won; Lee, Chang Hwan; Kim, Tae Kyoung; Son, Sang Hoon

    2009-09-01

    Implementation of Cu interconnects into Silicon Integrated Circuits (IC's) has been instrumental in the continuing improvement of IC device performance. Copper as a well known Gate Oxide Integrity (GOI) killer [1, 2] requires extensive protocols to minimize the possibility of cross contamination. Despite such protocols the risk for cross contamination exists, and consequently there is the need for in-line Cu cross-contamination detection metrology. Preferably the metrology will be non-destructive, fast, and capable of mapping on product wafers. Up to now the most common approaches for monitoring Cu contamination in IC fabrication lines either measure Cu in the bulk Si, which is not applicable to Cu cross-contamination monitoring because Back-End-of-the-Line thermal budgets restrict the ability to diffuse the surface Cu into the bulk Si; or the techniques are not optimal for in-line monitoring due to their destructive, time-consuming, or costly nature. In this work we demonstrate for the first time the application of the ac-Surface Photo Voltage (ac-SPV) surface lifetime approach [3] to in-line, full wafer coverage mapping of low level (metrology system. Furthermore, because the metrology is non-contact (utilizing edge-grip handling) and non-destructive, it is directly applicable to measurement of production wafers. In-line fab data acquired using this metrology is presented and compared to data from Inductively Coupled Plasma Mass Spectroscopy (ICP-MS).

  18. Bioaccessibility of barium from barite contaminated soils based on gastric phase in vitro data and plant uptake.

    Science.gov (United States)

    Abbasi, Sedigheh; Lamb, Dane T; Palanisami, Thavamani; Kader, Mohammed; Matanitobua, Vitukawalu; Megharaj, Mallavarapu; Naidu, Ravi

    2016-02-01

    Barite contamination of soil commonly occurs from either barite mining or explorative drilling operations. This work reported in vitro data for barite contaminated soils using the physiologically based extraction test (PBET) methodology. The existence of barite in plant tissue and the possibility of 'biomineralised' zones was also investigated using Scanning Electron Microscopy. Soils with low barium (Ba) concentrations showed a higher proportion of Ba extractability than barite rich samples. Barium uptake to spinach from soil was different between short term spiking studies and field weathered soils. Furthermore, Ba crystals were not evident in spinach tissue or acid digest solutions grown in barium nitrate spiked soils despite high accumulation. Barite was found in the plant digest solutions from barite contaminated soils only. Results indicate that under the conservative assumptions made, a child would need to consume extreme quantities of soil over an extended period to cause chronic health problems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. A mycological baseline study based on a multidisciplinary approach in a coastal area affected by contaminated torrent input.

    Science.gov (United States)

    Capello, M; Carbone, C; Cecchi, G; Consani, S; Cutroneo, L; Di Piazza, S; Greco, G; Tolotti, R; Vagge, G; Zotti, M

    2017-06-15

    Fungi include a vast group of eukaryotic organisms able to colonise different natural, anthropised and extreme environments, including marine areas contaminated by metals. The present study aims to give a first multidisciplinary characterisation of marine bottom sediments contaminated by metals (Cd, Co, Cr, Cu, Ni, and Zn), originating in the water leakage from an abandoned Fe-Cu sulphide mine (Libiola, north-western Italy), and evaluate how the chemical and physical parameters of water and sediments may affect the benthic fungal communities. Our preliminary results showed the high mycodiversity of the marine sediments studied (13 genera and 23 species of marine fungi isolated), and the great physiological adaptability that this mycobiota evolved in reaction to the effects of the ecotoxic bottom sediment contamination, and associated changes in the seawater parameters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Research on presentation and query service of geo-spatial data based on ontology

    Science.gov (United States)

    Li, Hong-wei; Li, Qin-chao; Cai, Chang

    2008-10-01

    The paper analyzed the deficiency on presentation and query of geo-spatial data existed in current GIS, discussed the advantages that ontology possessed in formalization of geo-spatial data and the presentation of semantic granularity, taken land-use classification system as an example to construct domain ontology, and described it by OWL; realized the grade level and category presentation of land-use data benefited from the thoughts of vertical and horizontal navigation; and then discussed query mode of geo-spatial data based on ontology, including data query based on types and grade levels, instances and spatial relation, and synthetic query based on types and instances; these methods enriched query mode of current GIS, and is a useful attempt; point out that the key point of the presentation and query of spatial data based on ontology is to construct domain ontology that can correctly reflect geo-concept and its spatial relation and realize its fine formalization description.

  1. Process design of high-concentration benzimidazole wastewater treatment based on the molecular structure of contaminants.

    Science.gov (United States)

    Li, Chenru; Qian, Kun; Liu, Qinyao; Zhang, Qianyi; Yao, Chen; Song, Wei; Wang, Yihong

    2018-04-01

    Benzimidazole is an important intermediate in industry and it is usually difficult to be degraded by many treatment technologies. Looking for a highly effective, environment-friendly degradation process for benzimidazole wastewater is of great significance to reduce pollution. Based on the structure of contaminants, the micro-electrolysis (ME) coupled with the Fenton technique was chosen to degrade the industrial benzimidazole wastewater. Special feeding was applied to maintain the suitable hydrogen peroxide (H 2 O 2 ) concentration to produce the hydroxyl radicals (•OH) as much as possible and protect •OH from being quenched by excess H 2 O 2 according to the reaction mechanism. The results showed that this combined technique was highly efficient to decompose benzimidazole compounds. More chemical oxygen demand (COD) could be reduced when flow control was used, compared to the flow not being controlled. The COD removal rate could reach 85.2% at optimal parameters. Then the effluent of this process was combined with the existing biochemical system for further degradation. The studies of Ultraviolet Spectrophotometry, Fourier Transform Infrared Spectroscopy and Liquid Chromatography Mass Spectrometry showed that both 2-(a-Hydroxyethyl) benzimidazole and 2-Acetylbenzimidazole were decomposed to the isopropanolamine and aniline after the ME treatment; then the intermediates were oxidized into oxalic acid after the Fenton reaction.

  2. Novel cell-based assay for detection of thyroid receptor beta-interacting environmental contaminants.

    Science.gov (United States)

    Stavreva, Diana A; Varticovski, Lyuba; Levkova, Ludmila; George, Anuja A; Davis, Luke; Pegoraro, Gianluca; Blazer, Vicki; Iwanowicz, Luke; Hager, Gordon L

    2016-08-10

    Even though the presence of endocrine disrupting chemicals (EDCs) with thyroid hormone (TH)-like activities in the environment is a major health concern, the methods for their efficient detection and monitoring are still limited. Here we describe a novel cell assay, based on the translocation of a green fluorescent protein (GFP)-tagged chimeric molecule of glucocorticoid receptor (GR) and the thyroid receptor beta (TRβ) from the cytoplasm to the nucleus in the presence of TR ligands. Unlike the constitutively nuclear TRβ, this GFP-GR-TRβ chimera is cytoplasmic in the absence of hormone while translocating to the nucleus in a time- and concentration-dependent manner upon stimulation with triiodothyronine (T3) and thyroid hormone analogue, TRIAC, while the reverse triiodothyronine (3,3',5'-triiodothyronine, or rT3) was inactive. Moreover, GFP-GR-TRβ chimera does not show any cross-reactivity with the GR-activating hormones, thus providing a clean system for the screening of TR beta-interacting EDCs. Using this assay, we demonstrated that Bisphenol A (BPA) and 3,3',5,5'-Tetrabromobisphenol (TBBPA) induced GFP-GR-TRβ translocation at micro molar concentrations. We screened over 100 concentrated water samples from different geographic locations in the United States and detected a low, but reproducible contamination in 53% of the samples. This system provides a novel high-throughput approach for screening for endocrine disrupting chemicals (EDCs) interacting with TR beta. Published by Elsevier Ireland Ltd.

  3. Novel cell-based assay for detection of thyroid receptor beta-interacting environmental contaminants

    International Nuclear Information System (INIS)

    Stavreva, Diana A.; Varticovski, Lyuba; Levkova, Ludmila; George, Anuja A.; Davis, Luke; Pegoraro, Gianluca; Blazer, Vicki; Iwanowicz, Luke; Hager, Gordon L.

    2016-01-01

    Even though the presence of endocrine disrupting chemicals (EDCs) with thyroid hormone (TH)-like activities in the environment is a major health concern, the methods for their efficient detection and monitoring are still limited. Here we describe a novel cell assay, based on the translocation of a green fluorescent protein (GFP)—tagged chimeric molecule of glucocorticoid receptor (GR) and the thyroid receptor beta (TRβ) from the cytoplasm to the nucleus in the presence of TR ligands. Unlike the constitutively nuclear TRβ, this GFP-GR-TRβ chimera is cytoplasmic in the absence of hormone while translocating to the nucleus in a time- and concentration-dependent manner upon stimulation with triiodothyronine (T3) and thyroid hormone analogue, TRIAC, while the reverse triiodothyronine (3,3′,5′-triiodothyronine, or rT3) was inactive. Moreover, GFP-GR-TRβ chimera does not show any cross-reactivity with the GR-activating hormones, thus providing a clean system for the screening of TR beta-interacting EDCs. Using this assay, we demonstrated that Bisphenol A (BPA) and 3,3′,5,5′-Tetrabromobisphenol (TBBPA) induced GFP-GR-TRβ translocation at micro molar concentrations. We screened over 100 concentrated water samples from different geographic locations in the United States and detected a low, but reproducible contamination in 53% of the samples. This system provides a novel high-throughput approach for screening for endocrine disrupting chemicals (EDCs) interacting with TR beta.

  4. Radiological assessment of past, present and potential sources to environmental contamination in the Southern Urals and strategies for remedial measures (SUCON)

    Energy Technology Data Exchange (ETDEWEB)

    Aarkrog, A. [Risoe National Lab. (Denmark); Simmonds, J. [National Radiological Protection Board (United Kingdom); Strand, P. [Norwegian Radiation Protection Authority (Norway); Christensen, G. [Institute of Energy Technology (Norway); Salbu, B. [Agricultural Univ. of Norway (Norway)

    2000-12-01

    This report summarises work done on the SUCON Project during 1996-1999 (European Commission Contract No. FI4C-CT95-0001). The project has focused on three major objectives: 1) An assessment of the radiological consequences of the contamination of the South Urals and the Ob river system from the production of plutonium at 'Mayak', 2) The development of models to calculate doses to individuals and populations in the South Urals using environmental data, and 3) The intercomparison, harmonisation and standardisation of techniques used in dose reconstruction and specification of good practice in particular with regard to remedial measures. (au)

  5. Radiological assessment of past, present and potential sources to environmental contamination in the Southern Urals and strategies for remedial measures (SUCON)

    International Nuclear Information System (INIS)

    Aarkrog, A.; Simmonds, J.; Strand, P.; Christensen, G.; Salbu, B.

    2000-12-01

    This report summarises work done on the SUCON Project during 1996-1999 (European Commission Contract No. FI4C-CT95-0001). The project has focused on three major objectives: 1) An assessment of the radiological consequences of the contamination of the South Urals and the Ob river system from the production of plutonium at 'Mayak', 2) The development of models to calculate doses to individuals and populations in the South Urals using environmental data, and 3) The intercomparison, harmonisation and standardisation of techniques used in dose reconstruction and specification of good practice in particular with regard to remedial measures. (au)

  6. Development of contaminant detection system based on ultra-low field SQUID-NMR/MRI

    International Nuclear Information System (INIS)

    Tsunaki, S; Yamamoto, M; Hatta, J; Hatsukade, Y; Tanaka, S

    2014-01-01

    We have developed an ultra-low field (ULF) NMR/MRI system using an HTS-rf-SQUID and evaluated performance of the system as a contaminant detection system for foods and drinks. In this work, we measured 1D MRIs from water samples with or without various contaminants, such as aluminum and glass balls using the system. In the 1D MRIs, changes of the MRI spectra were detected, corresponding to positions of the contaminants. We measured 2D MRIs from food samples with and without a hole. In the 2D MRIs, the hole position in the sample was well visualized. These results show that the feasibility of the system to detect and localize contaminants in foods and drinks.

  7. Magnesium-Based Corrosion Nano-Cells For Reductive Transformation Of Contaminants

    Science.gov (United States)

    Magnesium, with its potential to reduce a variety of aqueous contaminants, unique self-limiting corrosion behavior affording long active life times, natural abundance, low cost, and environmentally friendly nature, promises to be an effective technology. However, nanoparticles o...

  8. Economics of place-based monitoring under the safe drinking water act, part I: spatial and temporal patterns of contaminants, and design of screening strategies.

    Science.gov (United States)

    Brands, Edwin; Rajagopal, R

    2008-08-01

    The goals of environmental legislation and associated regulations are to protect public health, natural resources, and ecosystems. In this context, monitoring programs should provide timely and relevant information so that the regulatory community can implement legislation in a cost-effective and efficient manner. The Safe Drinking Water Act (SDWA) of 1974 attempts to ensure that public water systems (PWSs) supply safe water to its consumers. As is the case with many other federal environmental statutes, SDWA monitoring has been implemented in relatively uniform fashion across the USA. In this three part series, spatial and temporal patterns in water quality data are utilized to develop, compare, and evaluate the economic performance of alternative place-based monitoring approaches to current monitoring practice. Under the Safe Drinking Water Act (SDWA), a common list of over 90 contaminants is analyzed nationwide using EPA-authorized laboratory procedures. National and state-level summaries of SDWA data have shown that not all contaminants occur in all places at all times. This hypothesis is confirmed and extended by showing that only a few (less than seven) contaminants are of concern in any one of 19 Iowa surface water systems studied. These systems collectively serve about 350,000 people and their sizes vary between 1,200 and 120,000. The distributions of contaminants found in these systems are positively skewed, with many non-detect measurements. A screening strategy to identify such contaminants in individual systems is presented. These findings have significant implications not only for the design of alternative monitoring programs, but also in multi-billion-dollar decisions that influence the course of future drinking water infrastructure, repair, and maintenance investments.

  9. Saponin-based adjuvants induce cross-presentation in dendritic cells by intracellular lipid body formation

    NARCIS (Netherlands)

    Brok, M.H. den; Bull, C.; Wassink, M.; Graaf, A.M.A. de; Wagenaars, J.A.L.; Minderman, M.; Thakur, M.; Amigorena, S.; Rijke, E.O.; Schrier, C.C.; Adema, G.J.

    2016-01-01

    Saponin-based adjuvants (SBAs) are being used in animal and human (cancer) vaccines, as they induce protective cellular immunity. Their adjuvant potency is a factor of inflammasome activation and enhanced antigen cross-presentation by dendritic cells (DCs), but how antigen cross-presentation is

  10. Effect of Varied Computer Based Presentation Sequences on Facilitating Student Achievement.

    Science.gov (United States)

    Noonen, Ann; Dwyer, Francis M.

    1994-01-01

    Examines the effectiveness of visual illustrations in computer-based education, the effect of order of visual presentation, and whether screen design affects students' use of graphics and text. Results indicate that order of presentation and choice of review did not influence student achievement; however, when given a choice, students selected the…

  11. A GIS-based approach to prevent contamination of groundwater at regional scale

    Science.gov (United States)

    Balderacchi, M.; Vischetti, C.; di Guardo, A.; Trevisan, M.

    2009-04-01

    Sustainable development is a fundamental objective of the European Union. Since 1991, the use of numerical models has been used to assess the environmental fate of pesticides (directive 91/414 EC). Since then, new approaches to assess pesticide contamination have been developed. This is an ongoing process, with approaches getting increasingly close to reality. Actually, there is a new challenge to integrate the most advanced and cost-effective monitoring strategies with simulation models so that reliable indicators of unsaturated flow and transport can be suitably mapped and coupled with other indicators related to productivity and sustainability. The most relevant role of GIS in the analysis of pesticide fate in soil is its application to process together input data and the results of distribution model based simulations of pesticide transport. FitoMarche is a GIS-based software tool that estimates pesticide movement in the unsaturated zone using MACRO 5 and it is able to simulate complex and real crop rotations at the regional scale. Crop rotation involves the sequential production of different plant species on the same land, every crop is characterized by different agricultural practices that involve the use of different pesticides at different doses. FitoMarche extracts MACRO input data from a series of geographic data sets (shapefiles) and an internal database, writes input files for MACRO, executes the simulation and extracts solute and water fluxes from MACRO output files. The study has been performed in the Marche region, located in central Italy along the Adriatic coast. Soil, climate, land use shapefiles were provided from public authorities, crop rotation schemes were estimated from ISTAT (the national statistics institute) 5th agricultural census database using a municipality detail and agricultural practices following the local customs. Two herbicides have been tested: "A" is employed on maize crop, and "B" on maize, sunflower and sugarbeet. In the

  12. Responsibility/Threat Overestimation Moderates the Relationship Between Contamination-Based Disgust and Obsessive-Compulsive Concerns About Sexual Orientation.

    Science.gov (United States)

    Ching, Terence H W; Williams, Monnica T; Siev, Jedidiah; Olatunji, Bunmi O

    2018-05-01

    Disgust has been shown to perform a "disease-avoidance" function in contamination fears. However, no studies have examined the relevance of disgust to obsessive-compulsive (OC) concerns about sexual orientation (e.g., fear of one's sexual orientation transforming against one's will, and compulsive avoidance of same-sex and/or gay or lesbian individuals to prevent that from happening). Therefore, we investigated whether the specific domain of contamination-based disgust (i.e., evoked by the perceived threat of transmission of essences between individuals) predicted OC concerns about sexual orientation, and whether this effect was moderated/amplified by obsessive beliefs, in evaluation of a "sexual orientation transformation-avoidance" function. We recruited 283 self-identified heterosexual college students (152 females, 131 males; mean age = 20.88 years, SD = 3.19) who completed three measures assessing disgust, obsessive beliefs, and OC concerns about sexual orientation. Results showed that contamination-based disgust (β = .17), responsibility/threat overestimation beliefs (β = .15), and their interaction (β = .17) each uniquely predicted OC concerns about sexual orientation, ts = 2.22, 2.50, and 2.90, ps contamination-based disgust accompanied by strong responsibility/threat overestimation beliefs predicted more severe OC concerns about sexual orientation, β = .48, t = 3.24, p contamination-based disgust, and exacerbated by responsibility/threat overestimation beliefs. Treatment for OC concerns about sexual orientation should target such beliefs.

  13. Test and application of a general process-based dynamic coastal mass-balance model for contaminants using data for radionuclides in the Dnieper-Bug estuary

    International Nuclear Information System (INIS)

    Hakanson, Lars; Lindgren, Dan

    2009-01-01

    In this work a general, process-based mass-balance model for water contaminants for coastal areas at the ecosystem scale (CoastMab) is presented and for the first time tested for radionuclides. The model is dynamic, based on ordinary differential equations and gives monthly predictions. Connected to the core model there is also a sub-model for contaminant concentrations in fish. CoastMab calculates sedimentation, resuspension, diffusion, mixing, burial and retention of the given contaminant. The model contains both general algorithms, which apply to all contaminants, and substance-specific parts (such as algorithms for the particulate fraction, diffusion, biouptake and biological half-life). CoastMab and the sub-model for fish are simple to apply in practice since all driving variables may be readily accessed from maps or regular monitoring programs. The separation between the surface-water layer and the deep-water layer is not done as in most traditional models from water temperature data but from sedimentological criteria. Previous versions of the models for phosphorus and suspended particulate matter (in the Baltic Sea) have been validated and shown to predict well. This work presents modifications of the model and tests using two tracers, radiocesium and radiostrontium (from the Chernobyl fallout) in the Dnieper-Bug estuary (the Black Sea). Good correlations are shown between modeled and empirical data, except for the month directly after the fallout. We have, e.g., shown that: 1. The conditions in the sea outside the bay are important for the concentrations of the substances in water, sediments and fish within the bay, 2. We have demonstrated 'biological,' 'chemical' and 'water' dilution, 3. That the water chemical conditions in the bay influence biouptake and concentrations in fish of the radionuclides and 4. That the feeding behaviour of the coastal fish is very important for the biouptake of the radionuclides

  14. Impact of Contaminants Present in Coal-Biomass Derived Synthesis Gas on Water-gas Shift and Fischer-Tropsch Synthesis Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gokhan [TDA Research, Inc., Wheat Ridge, CO (United States)

    2013-02-15

    Co-gasification of biomass and coal in large-scale, Integrated Gasification Combined Cycle (IGCC) plants increases the efficiency and reduces the environmental impact of making synthesis gas ("syngas") that can be used in Coal-Biomass-to-Liquids (CBTL) processes for producing transportation fuels. However, the water-gas shift (WGS) and Fischer-Tropsch synthesis (FTS) catalysts used in these processes may be poisoned by multiple contaminants found in coal-biomass derived syngas; sulfur species, trace toxic metals, halides, nitrogen species, the vapors of alkali metals and their salts (e.g., KCl and NaCl), ammonia, and phosphorous. Thus, it is essential to develop a fundamental understanding of poisoning/inhibition mechanisms before investing in the development of any costly mitigation technologies. We therefore investigated the impact of potential contaminants (H2S, NH3, HCN, AsH3, PH3, HCl, NaCl, KCl, AS3, NH4NO3, NH4OH, KNO3, HBr, HF, and HNO3) on the performance and lifetime of commercially available and generic (prepared in-house) WGS and FT catalysts.

  15. Cell-based metabolomics for assessing chemical exposure and toxicity of environmental surface waters (presentation)

    Science.gov (United States)

    Introduction: Waste water treatment plants (WWTPs), concentrated animal feeding operations (CAFOs), mining activities, and agricultural operations release contaminants that negatively affect surface water quality. Traditional methods using live animals (e.g. fish) to monitor/as...

  16. Nano-TiO2-based photocatalytic disinfection of environmental surfaces contaminated by meticillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Petti, S; Messano, G A

    2016-05-01

    Traditional cleaning and disinfection methods are inefficient for complete decontamination of hospital surfaces from meticillin-resistant Staphylococcus aureus (MRSA). Additional methods, such as nano-TiO2-based photocatalytic disinfection (PCD), could be helpful. To evaluate anti-MRSA activity of PCD on polyvinyl chloride (PVC) surfaces in natural-like conditions. Two identical PVC surfaces were used, and nano-TiO2 was incorporated into one of them. The surfaces were contaminated with MRSA isolated from hospitalized patients using a mist sprayer to simulate the mode of environmental contamination caused by a carrier. MRSA cell density was assessed before contamination until 180min after contamination using Rodac plates. The differences between test and control surfaces in terms of MRSA density and log MRSA density reduction were assessed using parametric and non-parametric statistical tests. Five strains were tested, and each strain was tested five times. The highest median MRSA densities [46.3 and 43.1 colony-forming units (cfu)/cm(2) for control and test surfaces, respectively] were detected 45min after contamination. Median MRSA densities 180min after contamination were 10.1 and 0.7cfu/cm(2) for control and test surfaces, respectively (Pdisinfectant activity remained stable throughout the 25 testing occasions, despite between-test cleaning and disinfection. The anti-MRSA activity of PCD was compatible with the benchmark for surface hygiene in hospitals (surfaces. However, for clinical surfaces, PCD should be regarded as supplemental to conventional decontamination procedures, rather than an alternative. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  17. Identification of candidate biomarkers of the exposure to PCBs in contaminated cattle: A gene expression- and proteomic-based approach.

    Science.gov (United States)

    Girolami, F; Badino, P; Spalenza, V; Manzini, L; Renzone, G; Salzano, A M; Dal Piaz, F; Scaloni, A; Rychen, G; Nebbia, C

    2018-05-28

    Dioxins and polychlorinated biphenyls (PCBs) are widespread and persistent contaminants. Through a combined gene expression/proteomic-based approach, candidate biomarkers of the exposure to such environmental pollutants in cattle subjected to a real eco-contamination event were identified. Animals were removed from the polluted area and fed a standard ration for 6 months. The decontamination was monitored by evaluating dioxin and PCB levels in pericaudal fat two weeks after the removal from the contaminated area (day 0) and then bimonthly for six months (days 59, 125 and 188). Gene expression measurements demonstrated that CYP1B1 expression was significantly higher in blood lymphocytes collected in contaminated animals (day 0), and decreased over time during decontamination. mRNA levels of interleukin 2 showed an opposite quantitative trend. MALDI-TOF-MS polypeptide profiling of serum samples ascertained a progressive decrease (from day 0 to 188) of serum levels of fibrinogen β-chain and serpin A3-7-like fragments, apolipoprotein (APO) C-II and serum amyloid A-4 protein, along with an augmented representation of transthyretin isoforms, as well as APOC-III and APOA-II proteins during decontamination. When differentially represented species were combined with serum antioxidant, acute phase and proinflammatory protein levels already ascertained in the same animals (Cigliano et al., 2016), bioinformatics unveiled an interaction network linking together almost all components. This suggests the occurrence of a complex PCB-responsive mechanism associated with animal contamination/decontamination, including a cohort of protein/polypeptide species involved in blood redox homeostasis, inflammation and lipid transport. All together, these results suggest the use in combination of such biomarkers for identifying PCB-contaminated animals, and for monitoring the restoring of their healthy condition following a decontamination process. Copyright © 2018 Elsevier B.V. All

  18. Restoration of contaminated soils

    International Nuclear Information System (INIS)

    Miranda J, Jose Eduardo

    2009-01-01

    A great variety of techniques are used for the restoration of contaminated soils. The contamination is present by both organic and inorganic pollutants. Environmental conditions and soil characteristics should take into account in order to implement a remedial technique. The bioremediation technologies are showed as help to remove a variety of soil contaminants. (author) [es

  19. Aqueous contaminant detection via UiO-66 thin film optical fiber sensor platform with fast Fourier transform based spectrum analysis

    Science.gov (United States)

    Nazari, Marziyeh; Rubio-Martinez, Marta; Babarao, Ravichandar; Ayad Younis, Adel; Collins, Stephen F.; Hill, Matthew R.; Duke, Mikel C.

    2018-01-01

    Routine water quality monitoring is required in drinking and waste water management. A particular interest is to measure concentrations of a range of diverse contaminants on-site or remotely in real time. Here we present metal organic framework (MOF) integrated optical fiber sensor that allows for rapid optical measurement based on fast Fourier transform (FFT) spectrum analysis. The end-face of these glass optical fibers was modified with UiO-66(Zr) MOF thin film by in situ hydrothermal synthesis for the detection of the model contaminants, Rhodamine-B and 4-Aminopyridine, in water. The sensing mechanism is based on the change in the optical path length of the thin film induced by the adsorption of chemical molecules by UiO-66. Using FFT analysis, various modes of interaction (physical and chemical) became apparent, showing both irreversible changes upon contact with the contaminant, as well as reversible changes according to actual concentration. This was indicated by the second harmonic elevation to a certain level translating to high sensitivity detection.

  20. The Legacy of Arsenic Contamination from Giant Mine, Northern Canada: An Assessment of Impacts Based on Lake Water and Lake Sediment Core Analysis

    Science.gov (United States)

    Blais, J. M.; Korosi, J.

    2016-12-01

    The Giant Mine, which operated between 1948 and 2004 and located near the City of Yellowknife (Northwest Territories, Canada), has left a legacy of arsenic, antimony, and mercury contamination extending to the present day. Over 20,000 tonnes of arsenic trioxide dust was released from roaster stack emissions during its first 10 years of operations, leading to a significant contamination of the surrounding landscape. Here we present a summary of impacts by the recent contamination from Giant Mine on the surrounding region. A survey we conducted of 25 lakes of the region in 2010 revealed that most lake water within a 15 km radius of the roaster stack had arsenic concentrations in water > 10 mg/L, the standard for drinking water, with concentrations declining exponentially with increasing distance from the roaster stack. Sediment cores from lakes were collected near the Giant Mine roaster stack and radiometrically dated by 137Cs and excess 210Pb. Arsenic concentrations in these sediments increased by 1700% during the 1950s and 60s, consistent with the history of arsenic releases from roaster emissions. Correspondingly, pelagic diatoms and cladocerans were extirpated from one lake during this period, based on microfossil analysis of lake sediment deposits. Sediment core analysis further showed that this lake ecosystem has not recovered, even ten years after closure of the mine. Likely causes for the lack of recent recovery are explored with the use of sediment toxicity bioassays, using a novel paleo-ecotoxicological approach of using toxicity assessments of radiometrically dated lake sediment horizons.

  1. Auto-correlation based intelligent technique for complex waveform presentation and measurement

    International Nuclear Information System (INIS)

    Rana, K P S; Singh, R; Sayann, K S

    2009-01-01

    Waveform acquisition and presentation forms the heart of many measurement systems. Particularly, data acquisition and presentation of repeating complex signals like sine sweep and frequency-modulated signals introduces the challenge of waveform time period estimation and live waveform presentation. This paper presents an intelligent technique, for waveform period estimation of both the complex and simple waveforms, based on the normalized auto-correlation method. The proposed technique is demonstrated using LabVIEW based intensive simulations on several simple and complex waveforms. Implementation of the technique is successfully demonstrated using LabVIEW based virtual instrumentation. Sine sweep vibration waveforms are successfully presented and measured for electrodynamic shaker system generated vibrations. The proposed method is also suitable for digital storage oscilloscope (DSO) triggering, for complex signals acquisition and presentation. This intelligence can be embodied into the DSO, making it an intelligent measurement system, catering wide varieties of the waveforms. The proposed technique, simulation results, robustness study and implementation results are presented in this paper.

  2. A Discovery-Based Experiment Illustrating How Iron Metal Is Used to Remediate Contaminated Groundwater

    Science.gov (United States)

    Balko, Barbara A.; Tratnyek, Paul G.

    2001-12-01

    In this article, we describe an experiment for undergraduate general chemistry in which students investigate the chemistry behind iron-permeable reactive barriers (iron PRBs), a new technology that is widely used to remediate contaminated groundwater. Contaminant remediation involving iron PRBs is a redox process: the iron metal undergoes oxidative dissolution while the contaminant is reduced. The reaction is complicated, however, by the fact that it involves a surface that changes owing to the development of a layer of rust (iron oxide) on the iron. In this experiment, students examine the iron PRB-contaminant reaction by characterizing the kinetics of the degradation of a dye (the model contaminant) in the presence of granular iron under various experimental conditions. Students can be asked to design their own experiments to investigate aspects of the degradation reaction that are of particular interest to them. The material covered in the lab includes oxidation-reduction reactions, pseudo first-order kinetics, spectrophotometry, and the application of chemistry to solving environmental problems. The experiment can also be used as a vehicle to introduce more advanced topics in chemistry such as heterogeneous reactions, corrosion, passive film growth, and mass transport.

  3. Contamination-remedying technology based on biotechnology. ; Bioremediation. Biotechnology wo mochiita osen shufuku gijutsu. ; Bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, M [The Japan Research Institute, Ltd., Osaka (Japan)

    1993-08-01

    Bioremediation technology is outlined. The bioremediation technology is a contamination-remedying technology for the injurious chemical matter discharged in the environment to be made innocuous by utilizing the decomposing ability of microorganisms. That technology is characterized by its energywise economical performance, secondary waste which is not producible and remedy which is possible on site against the contamination. As a treatment system, that technology comprises solid phase bioremediation (The contaminated soil is purified in a soil treatment unit.), slurry phase bioremediation (The contaminated soil is made slurry and decomposed by microorganisms.) and in-situ bioremediation (The treatment is made by injecting nutrients and microorganisms underground.). As for how to use the microorganisms, there are two methods: One in which living groups of microorganisms are activated and the other in which microorganisms are artificially cultivated. As contaminants in the US, listed are organic solvent, wood preservative, high-molecular aromatic halide, agricultural chemical, military waste, heavy metal waste and radioactive waste. 11 refs., 5 figs., 1 tab.

  4. Microlith-Based Catalytic Reactor for Air Quality and Trace Contaminant Control Applications

    Science.gov (United States)

    Vilekar, Saurabh; Hawley, Kyle; Junaedi, Christian; Crowder, Bruce; Prada, Julian; Mastanduno, Richard; Perry, Jay L.; Kayatin, Matthew J.

    2015-01-01

    Traditionally, gaseous compounds such as methane, carbon monoxide, and trace contaminants have posed challenges for maintaining clean air in enclosed spaces such as crewed spacecraft cabins as they are hazardous to humans and are often difficult to remove by conventional adsorption technology. Catalytic oxidizers have provided a reliable and robust means of disposing of even trace levels of these compounds by converting them into carbon dioxide and water. Precision Combustion, Inc. (PCI) and NASA - Marshall (MSFC) have been developing, characterizing, and optimizing high temperature catalytic oxidizers (HTCO) based on PCI's patented Microlith® technology to meet the requirements of future extended human spaceflight explorations. Current efforts have focused on integrating the HTCO unit with a compact, simple recuperative heat exchanger to reduce the overall system size and weight while also reducing its energy requirements. Previous efforts relied on external heat exchangers to recover the waste heat and recycle it to the oxidizer to minimize the system's power requirements; however, these units contribute weight and volume burdens to the overall system. They also result in excess heat loss due to the separation of the HTCO and the heat recuperator, resulting in lower overall efficiency. Improvements in the recuperative efficiency and close coupling of HTCO and heat recuperator lead to reductions in system energy requirements and startup time. Results from testing HTCO units integrated with heat recuperators at a variety of scales for cabin air quality control and heat melt compactor applications are reported and their benefits over previous iterations of the HTCO and heat recuperator assembly are quantified in this paper.

  5. 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

  6. Heavy Metal Contamination in the Sediments of Anzali International Wetland, Northern Iran Based on Type Regional Development

    Directory of Open Access Journals (Sweden)

    Saeed Ganjali

    2016-08-01

    Full Text Available Background: The most important factors and problems threatening the Anzali Wetland are the contaminant load and sediments entering the wetland, as well as lack of an integrated management plan for this wetland. The main objectives of the current research were to explore whether there are significant differences in concentrations of Zn, Cd, and Pb in surface sediments among different sites (based on type region development of the Anzali Wetland, Northern Iran. Methods: Through a field study, samples were collected from 10 stations based on the type of regional development and contaminant source inputs of Anzali Wetland in 2015. Using a hot-block digester, the sediment samples were digested with a 4:1 combination of nitric acid (HNO3 and perchloric acid (HCLO4 for one hour at 40 °C, followed by 3 h at 140 °C. Afterwards, samples were filtered with Whatman 42, filter paper and the filtrate was kept in polyethylene containers at 4 °C, until analysis by atomic absorption spectrometry (AAS. Results: Mean ± SD levels of metals in the sediments of different stations were 26.7 ± 3.49 (lead, 4.36 ± 0.47 (cadmium, and 88.44 ± 10.06 (zinc μg g-1 dw. There was a significant difference between the stations of the wetland (P < 0.05. This difference could be due to the variations in the input of contaminant sources into the Anzali Wetland. Conclusions: The areas, affected by urban and industrial developments, had the highest level of contamination while the agricultural and less-developed areas had the lowest level of contamination, and therefore, protective plans must be implemented in developed areas in order to lower the level of heavy metals.

  7. GIS-BASED location optimization of a biomass conversion plant on contaminated willow in the Campine region (Belgium)

    International Nuclear Information System (INIS)

    Voets, Thomas; Neven, An; Thewys, Theo; Kuppens, Tom

    2013-01-01

    The Campine region is diffusely contaminated with heavy metals like cadmium. Since traditional excavation techniques are too expensive, phytoremediation is preferred as a remediation technique. In a previous study, the biomass potential from phytoremediation of contaminated agricultural land in the Campine region in Belgium was assessed. Based on recently upgraded figures of willow potential from phytoremediation on agricultural land in the seven most contaminated municipalities of the Belgian Campine region, the current paper uses GIS-knowledge to investigate which of three previously identified locations is most suitable for a biomass plant, taking into account the spatial distribution of the contaminated willow supply and the total cost of willow transport. Biomass transport distance from the centroid of each contaminated agricultural parcel to each of the three potential biomass plant locations was determined following Euclidian distance calculations and distance calculations over the existing road network. A transport cost model consisting of distance fixed and distance dependent biomass transport costs was developed. Of the locations identified, the Overpelt Fabriek site results in the lowest biomass transport distance and costs. When willow allocation for each parcel occurs based on the nearest potential plant location, transport costs are on average 23% lower than when all biomass is transported to the single Overpelt Fabriek site location. Therefore, when only considering transport costs, installing a smaller plant at each of the three potential plant locations would be less expensive than when installing a single biomass plant at the Overpelt Fabriek site. -- Highlights: ► Overpelt Fabriek site most attractive for time frames considered. ► Average tortuosity factor in Campine region between 1.27 and 1.42. ► Share of willow transport costs in willow supply costs 21%. ► Optimal allocation of willow results in lower transport costs

  8. JUSTIFICATION FOR THE RADIOLOGICAL CRITERIA FOR THE USE OF AREAS WITH RESIDUAL RADIOACTIVE CONTAMINATION BASED ON THE DOSE APPROACH

    Directory of Open Access Journals (Sweden)

    V. Yu. Golikov

    2017-01-01

    Full Text Available The article presents a methodology for assessing the radiological criteria for the use of the territory (a land plot with buildings with residual radioactive contamination from the so-called “green area”, i.e., complete release from radiation control until a number of restrictions are imposed on the use of the territory. In accordance with the further use of the territory, a range of scenarios and pathways for the exposure of the population was considered. A set of models and their parameters, corresponding to the number of the considered pathways of exposure, was defined. Assuming a uniform distribution of a radionuclide with a unit concentration in the source zone, the distribution of effective doses for the population living in the territory with the residual radioactive contamination for different irradiation scenarios was calculated by stochastic modeling, 95% of the quantile of which was attributed to the dose in the representatives of the critical population group. Next, the value of radiological criteria, depending on the implemented scenario, was determined as the ratio of the dose constraint EL = 0,3 mSv/yr and 95% quantile in the distribution of the effective dose from a unit contamination. The numerical values of radiological criteria for the presence of radionuclides in the soil are presented, both for the radiation scenarios that correspond to the permanent residence of the population in the contaminated territory and for recreational use. A further consideration is given to the so-called worker scenario, which corresponds to the limited time spent on the contaminated territory and the simultaneous effects of radionuclides contained both in the soil and in the construction of the buildings. A comparison of the results of the own calculations with the data of other authors was carried out.

  9. Identification of immiscible NAPL contaminant sources in aquifers by a modified two-level saturation based imperialist competitive algorithm

    Science.gov (United States)

    Ghafouri, H. R.; Mosharaf-Dehkordi, M.; Afzalan, B.

    2017-07-01

    A simulation-optimization model is proposed for identifying the characteristics of local immiscible NAPL contaminant sources inside aquifers. This model employs the UTCHEM 9.0 software as its simulator for solving the governing equations associated with the multi-phase flow in porous media. As the optimization model, a novel two-level saturation based Imperialist Competitive Algorithm (ICA) is proposed to estimate the parameters of contaminant sources. The first level consists of three parallel independent ICAs and plays as a pre-conditioner for the second level which is a single modified ICA. The ICA in the second level is modified by dividing each country into a number of provinces (smaller parts). Similar to countries in the classical ICA, these provinces are optimized by the assimilation, competition, and revolution steps in the ICA. To increase the diversity of populations, a new approach named knock the base method is proposed. The performance and accuracy of the simulation-optimization model is assessed by solving a set of two and three-dimensional problems considering the effects of different parameters such as the grid size, rock heterogeneity and designated monitoring networks. The obtained numerical results indicate that using this simulation-optimization model provides accurate results at a less number of iterations when compared with the model employing the classical one-level ICA. A model is proposed to identify characteristics of immiscible NAPL contaminant sources. The contaminant is immiscible in water and multi-phase flow is simulated. The model is a multi-level saturation-based optimization algorithm based on ICA. Each answer string in second level is divided into a set of provinces. Each ICA is modified by incorporating a new knock the base model.

  10. AFLATOXIN B1 IN CORN: DIRECT VERIFICATION OF CONTAMINATION THROUGH AN AUTOMATIC COMPUTERIZED SYSTEM BASED ON THE FLUORESCENCE

    Directory of Open Access Journals (Sweden)

    L. Vallone

    2009-09-01

    Full Text Available “Aflaflesh” is a computer based instrument, designed combining a visual data acquisition system with a sophisticated software of acquisition and analysis of images. This system allows you to check on a representative sample (5/10 kg contamination of corn by AFB1, using fluorescence under UV light when the grain is contaminated. To optimize the use of this control equipment were analyzed in two phases, a total of 80 samples comparing the results obtained by chemical analysis (Hplc to those obtained using “Aflaflesh”. Initially the study was set to correlate the number of contaminated grains to the ppb read by the official method, Hplc; the second step was to correlate ppb values to the number of pixel of contaminated surface of the grains read by the “Aflaflesh” instrument. The apparatus was then calibrated through a statistical analysis of the results obtained, to allow a direct reading of the AFB1 concentrations in a short period of time (15 min without the assistance of specialized personnel.

  11. Field-based evidence for consistent responses of bacterial communities to copper contamination in two contrasting agricultural soils

    Directory of Open Access Journals (Sweden)

    Jing eLi

    2015-02-01

    Full Text Available Copper contamination on China’s arable land could pose severe economic, ecological and healthy consequences in the coming decades. As the drivers in maintaining ecosystem functioning, the responses of soil microorganisms to long-term copper contamination in different soil ecosystems are still debated. This study investigated the impacts of copper gradients on soil bacterial communities in two agricultural fields with contrasting soil properties. Our results revealed consistent reduction in soil microbial biomass carbon (SMBC with increasing copper levels in both soils, coupled by significant declines in bacterial abundance in most cases. Despite of contrasting bacterial community structures between the two soils, the bacterial diversity in the copper-contaminated soils showed considerably decreasing patterns when copper levels elevated. High-throughput sequencing revealed copper selection for major bacterial guilds, in particular, Actinobacteria showed tolerance, while Acidobacteria and Chloroflexi were highly sensitive to copper. The thresholds that bacterial communities changed sharply were 800 and 200 added copper mg kg-1 in the fluvo-aquic soil and red soil, respectively, which were similar to the toxicity thresholds (EC50 values characterized by SMBC. Structural equation model (SEM analysis ascertained that the shifts of bacterial community composition and diversity were closely related with the changes of SMBC in both soils. Our results provide field-based evidence that copper contamination exhibits consistently negative impacts on soil bacterial communities, and the shifts of bacterial communities could have largely determined the variations of the microbial biomass.

  12. Developing GIS based decision-making tools in case of radiological contamination of agricultural soil

    International Nuclear Information System (INIS)

    Kepka, Pavel; Brom, Jakub; Prochazka, Jan; Vincikova, Hana; Pecharova, Emilie

    2010-01-01

    A set of supporting tools to help take remedial decisions in case of radiological contamination of agricultural produce is being developed within the EURANOS project. The tools are created in the ArcGIS environment in the Python programming language. So far, a simple model to estimate biomass in the contaminated area has been set up. This module will make it possible to estimate additional parameters, such as activity per kg or amount of waste created, which are useful when taking decision regarding premature crops harvesting. Areas where no remedial action is required can be also identified, of course

  13. Eosinophilic granuloma of the skull base: patient with unique clinical moreover, radiographic presentation.

    Directory of Open Access Journals (Sweden)

    Hosein Dalili

    2015-01-01

    Full Text Available This case report presents an eight-year-old girl having periauricular swelling and severe pain during mouth opening on the right-side temporomandibular joint (TMJ. CBCT showed extensive destruction of the base of the skull and the roof of the glenoid fossa on the right side. The findings based on CT and MRI images with and without contrast are discussed herein. This report highlights a skull base eosinophilic granuloma that mimics TMJ disorder and the importance of proper evaluation of CBCT images to make an early diagnosis.

  14. The oral case presentation: toward a performance-based rhetorical model for teaching and learning

    Directory of Open Access Journals (Sweden)

    Mei Yuit Chan

    2015-07-01

    Full Text Available The oral case presentation is an important communicative activity in the teaching and assessment of students. Despite its importance, not much attention has been paid to providing support for teachers to teach this difficult task to medical students who are novices to this form of communication. As a formalized piece of talk that takes a regularized form and used for a specific communicative goal, the case presentation is regarded as a rhetorical activity and awareness of its rhetorical and linguistic characteristics should be given due consideration in teaching. This paper reviews practitioners’ and the limited research literature that relates to expectations of medical educators about what makes a good case presentation, and explains the rhetorical aspect of the activity. It is found there is currently a lack of a comprehensive model of the case presentation that projects the rhetorical and linguistic skills needed to produce and deliver a good presentation. Attempts to describe the structure of the case presentation have used predominantly opinion-based methodologies. In this paper, I argue for a performance-based model that would not only allow a description of the rhetorical structure of the oral case presentation, but also enable a systematic examination of the tacit genre knowledge that differentiates the expert from the novice. Such a model will be a useful resource for medical educators to provide more structured feedback and teaching support to medical students in learning this important genre.

  15. The oral case presentation: toward a performance-based rhetorical model for teaching and learning

    Science.gov (United States)

    Chan, Mei Yuit

    2015-01-01

    The oral case presentation is an important communicative activity in the teaching and assessment of students. Despite its importance, not much attention has been paid to providing support for teachers to teach this difficult task to medical students who are novices to this form of communication. As a formalized piece of talk that takes a regularized form and used for a specific communicative goal, the case presentation is regarded as a rhetorical activity and awareness of its rhetorical and linguistic characteristics should be given due consideration in teaching. This paper reviews practitioners’ and the limited research literature that relates to expectations of medical educators about what makes a good case presentation, and explains the rhetorical aspect of the activity. It is found there is currently a lack of a comprehensive model of the case presentation that projects the rhetorical and linguistic skills needed to produce and deliver a good presentation. Attempts to describe the structure of the case presentation have used predominantly opinion-based methodologies. In this paper, I argue for a performance-based model that would not only allow a description of the rhetorical structure of the oral case presentation, but also enable a systematic examination of the tacit genre knowledge that differentiates the expert from the novice. Such a model will be a useful resource for medical educators to provide more structured feedback and teaching support to medical students in learning this important genre. PMID:26194482

  16. A heuristic two-dimensional presentation of microsatellite-based data applied to dogs and wolves

    Directory of Open Access Journals (Sweden)

    Foerster Martin

    2007-07-01

    Full Text Available Abstract Methods based on genetic distance matrices usually lose information during the process of tree-building by converting a multi-dimensional matrix into a phylogenetic tree. We applied a heuristic method of two-dimensional presentation to achieve a better resolution of the relationship between breeds and individuals investigated. Four hundred and nine individuals from nine German dog breed populations and one free-living wolf population were analysed with a marker set of 23 microsatellites. The result of the two-dimensional presentation was partly comparable with and complemented a model-based analysis that uses genotype patterns. The assignment test and the neighbour-joining tree based on allele sharing estimate allocated 99% and 97% of the individuals according to their breed, respectively. The application of the two-dimensional presentation to distances on the basis of the proportion of shared alleles resulted in comparable and further complementary insight into inferred population structure by multilocus genotype data. We expect that the inference of population structure in domesticated species with complex breeding histories can be strongly supported by the two-dimensional presentation based on the described heuristic method.

  17. Audit on first seizure presentation to Taranaki Base Hospital: a secondary centre experience.

    Science.gov (United States)

    Lance, Sean; Kumar, Rajesh

    2017-11-10

    Management of first seizure should be based on treating the underlying cause and tailoring investigations to identify those patients at high risk of recurrence. To establish the incidence of first seizure presentation to Taranaki Base Hospital and investigate the management of these patients. A retrospective audit was performed identifying patients presenting to Taranaki Base Hospital from 1 January 2015 to 31 December 2015 with a first seizure. Thirty-seven patients presented with their first seizure with 50% found to have an easily reversible precipitant. Forty-three percent had a history of previous brain insult and 52% had an abnormality identified on neuroimaging. Only 14% received formal neurology follow-up and only 8% had electroencephalography. Forty-three percent received chronic antiepileptic drug therapy and 27% had a recurrent seizure within 12 months. Only 43% had documented driving advice. The incidence of first seizure presentation to Taranaki Base Hospital is similar to worldwide data. In general, patients receive basic investigations in keeping with international guidelines. This audit has helped to identify a number of areas to address with the current service provision, including ways to improve access to important investigations and ways to develop a guideline to standardise care.

  18. The interplay between cost accounting knowledge and presentation formats in cost-based decision making

    NARCIS (Netherlands)

    Cardinaels, E.

    2008-01-01

    Most studies on cost-based decision-making examine the profit impact of cost reports that rely on different methods to allocate costs. In practice, firms’ cost reports often employ the same cost allocation method with subtle variations in the way that the cost data are presented. This paper examines

  19. SVM-based feature extraction and classification of aflatoxin contaminated corn using fluorescence hyperspectral data

    Science.gov (United States)

    Support Vector Machine (SVM) was used in the Genetic Algorithms (GA) process to select and classify a subset of hyperspectral image bands. The method was applied to fluorescence hyperspectral data for the detection of aflatoxin contamination in Aspergillus flavus infected single corn kernels. In the...

  20. Early detection of fungal contamination on green coffee by a MOX sensors based Electronic Nose

    International Nuclear Information System (INIS)

    Sberveglieri, V.; Pulvirenti, A.; Fava, P.; Concina, I.; Falasconi, M.; Gobbi, E.

    2011-01-01

    Fungal growth can occur on green coffee beans along all the distribution chain, eventually bringing on health hazards to consumers, because of the production of toxic metabolites (mycotoxins). Besides, the sensorial contamination due to volatiles by-products of fungal metabolism could cause defects on coffee also after roasting. Therefore, it is necessary to devise strategies to detect and quantify fungal infection and toxin production at early stages of the food chain. One of the most promising techniques is the analysis of volatile compounds in the headspace gas surrounding the samples. The aim of this work was to verify the ability of the Electronic Nose (EN EOS 835 ) to early detect the microbial contamination of Arabica green coffee. This EN is equipped with Metal Oxide Semiconductor sensor array. Gas chromatography coupled to mass spectrometry (GC-MS) analysis of the static headspace of non-contaminated Arabica green coffee samples was carried out to confirm the EN ability to provide satisfactory indications about the presence of contamination.

  1. On-site radioactive soil contamination at the Andreeva Bay shore technical base, Northwest Russia

    NARCIS (Netherlands)

    Reistad, O.; Dowdall, M.; Selnaes, O. G.; Standring, W. J. F.; Hustveit, S.; Steenhuisen, F.; Sorlie, A.

    The radioactive waste (RAW) storage site at Andreeva Bay in the Russian Northwest has experienced radioactive contamination both as a result of activities carried out at the site and due to incidents that have occurred there in the past such as accidental releases of radioactive materials. The site

  2. Bioremediation Of Groundwater Contaminated Wtih Gasoline Hydrocarbons And Oxygenates Using A Membrane-Based Reactor

    Science.gov (United States)

    The objective of this study was to operate a novel, field-scale, aerobic bioreactor and assess its performance in the ex situ treatment of groundwater contaminated with gasoline from a leaking underground storage tank in Pascoag, RI. The groundwater contained elevated concentrat...

  3. An efficient ERP-based brain-computer interface using random set presentation and face familiarity.

    Directory of Open Access Journals (Sweden)

    Seul-Ki Yeom

    Full Text Available Event-related potential (ERP-based P300 spellers are commonly used in the field of brain-computer interfaces as an alternative channel of communication for people with severe neuro-muscular diseases. This study introduces a novel P300 based brain-computer interface (BCI stimulus paradigm using a random set presentation pattern and exploiting the effects of face familiarity. The effect of face familiarity is widely studied in the cognitive neurosciences and has recently been addressed for the purpose of BCI. In this study we compare P300-based BCI performances of a conventional row-column (RC-based paradigm with our approach that combines a random set presentation paradigm with (non- self-face stimuli. Our experimental results indicate stronger deflections of the ERPs in response to face stimuli, which are further enhanced when using the self-face images, and thereby improving P300-based spelling performance. This lead to a significant reduction of stimulus sequences required for correct character classification. These findings demonstrate a promising new approach for improving the speed and thus fluency of BCI-enhanced communication with the widely used P300-based BCI setup.

  4. PREZI, CLOUD-BASED PRESENTATION, FOR TEACHING: HOW IS IT INTERESTING?

    Directory of Open Access Journals (Sweden)

    Santiana Santiana

    2017-08-01

    Full Text Available This study aims at analyzing reflection of the use of prezi as instructional media for teaching English in Indonesian context. Prezi is presentation software which is not commonly used in Indonesia producing a cloud-based presentation and storytelling tool for presenting ideas on a virtual canvas. This study is conducted based on the previous survey study done by Fox et.al (2016 finding that all of the students in their study preferred prezi rather than power point as a presentation tool in the areas of ease of use, fun to use, text, graphics, and usage in future presentations. However, this study has a purpose to reflect the student-teacher’s experience when using prezi in teaching English. To obtain the data, journal writing and self-observation by using video recording are used. It deeply investigates: 1 how he creates prezi for teaching English and 2 challenges and benefits of using it for teaching. The finding revealed that prezi is a powerful tool attracting the students’ attention which creates better classroom atmosphere and meaningful learning experience. On the other hand, it encourages the teacher to have high access of internet and be creative on making prezi presentation.

  5. Clinical Subtypes of Dementia with Lewy Bodies Based on the Initial Clinical Presentation.

    Science.gov (United States)

    Morenas-Rodríguez, Estrella; Sala, Isabel; Subirana, Andrea; Pascual-Goñi, Elba; Sánchez-Saudinós, MaBelén; Alcolea, Daniel; Illán-Gala, Ignacio; Carmona-Iragui, María; Ribosa-Nogué, Roser; Camacho, Valle; Blesa, Rafael; Fortea, Juan; Lleó, Alberto

    2018-06-04

    Dementia with Lewy bodies (DLB) is a heterogeneous disease in which clinical presentation, symptoms, and evolution widely varies between patients. To investigate the existence of clinical subtypes in DLB based on the initial clinical presentation. 81 patients with a clinical diagnosis of probable DLB were consecutively included. All patients underwent a neurological evaluation including a structured questionnaire about neuropsychiatric symptoms and sleep, an assessment of motor impairment (Unified Parkinson Disease Rating Scale subscale III), and a formal neuropsychological evaluation. Onset of core symptoms (hallucinations, parkinsonism, and fluctuations) and dementia were systematically reviewed from medical records. We applied a K-means clustering method based on the initial clinical presentation. Cluster analysis yielded three different groups. Patients in cluster I (cognitive-predominant, n = 46) presented more frequently with cognitive symptoms (95.7%, n = 44, p presented more frequently with psychotic symptoms (77.3%, n = 17), and had a shorter duration until the onset of hallucinations (p clinical DLB can be defined when considering the differential initial presentations. The proposed subtypes have distinct clinical profiles and progression patterns.

  6. Technology-Based Healthcare for Nursing Education Within The Netherlands: Past, Present and Future.

    Science.gov (United States)

    Koster, Ybranda; van Houwelingen, Cornelis T M

    2017-01-01

    At the present time, nearly all Dutch nursing schools are searching for suitable ways to implement technology-based healthcare in their curriculum. Some Universities chose elective education, others a mandatory solution. Several studies were executed to determine competencies needed by nurses in order to work with technology-based healthcare. In 2016 a nationwide new curriculum for nurses has been published. Providing technology-based healthcare is included under the core competencies of this new curriculum. All baccalaureate nursing educational institutes must implement this new curriculum at the start of 2016 which will have a huge impact on the implementation of technology-based healthcare in the education programs. In the future, technology centers from Universities will collaborate and specialize, partner with technology companies and crossovers between information and communication technology and healthcare education will be expanded.

  7. Limestone-based technosols: a suitable way for the remediation of sediments contaminated by heavy metals.

    Science.gov (United States)

    Martínez-Sanchez, Maria Jose; Garcia-Lorenzo, Mari Luz; Martínez, Salvadora; Gonzalez, Eva; Molina, Jose; Hernández, Carmen; Pérez-Sirvent, Carmen

    2013-04-01

    The aim of this work was to assess the suitability of limestone-based technosols for decreasing the toxicity of the leachates caused by rain in sites contaminated by heavy metals. For such a purpose, 64 technosols were prepared in containers of 0.75m3, filled with 4 types of sediments collected from Portman Bay and subjected to different stabilizer proportions (limestone filler), different thickness of a drainage layer and presence/absence of a topsoil cover. The technosols were then submitted to different humidity/dryness cycles simulating the usual rain conditions in the zone. Portman bay is situated close to the mining region of La Unión. The entire area around the bay was subject to mining from the time of the Roman Empire to 1991. Since 1957, the wastes from mining operations were discharged directly into the sea in the inner part of the bay, while later on, they were also discharged to sea at a distance of the shore. These wastes mainly consisted in ore materials (galena, pyrite and sphalerite), phyllosilicates, in addition to siderite, iron oxides and sometimes alteration products such as jarosite, alunite, kaolinite and greenalite. These materials have suffered a concentration process by floatation with sea water and as a result of the discharge, the whole of the bay has filled up with wastes which also extend into the Mediterranean Sea. The pH and the electrical conductivity (EC) was determined in obtained percolates, together with major ion content, determined by ionic chromatography. The Zn, Pb, Cd and Cu content was determined by electrothermal atomization atomic absorption spectrometry (ETAAS). The As content was measured by atomic fluorescence spectrometry. In addition, the mineralogical composition was determined in the evaporated samples by X-Ray diffraction. A battery of bioassays was applied for the ecotoxicological screening of obtained percolates . Particularly, the toxicity was evaluated by using three assays: microtox bioassay (Vibrio

  8. A novel brain-computer interface based on the rapid serial visual presentation paradigm.

    Science.gov (United States)

    Acqualagna, Laura; Treder, Matthias Sebastian; Schreuder, Martijn; Blankertz, Benjamin

    2010-01-01

    Most present-day visual brain computer interfaces (BCIs) suffer from the fact that they rely on eye movements, are slow-paced, or feature a small vocabulary. As a potential remedy, we explored a novel BCI paradigm consisting of a central rapid serial visual presentation (RSVP) of the stimuli. It has a large vocabulary and realizes a BCI system based on covert non-spatial selective visual attention. In an offline study, eight participants were presented sequences of rapid bursts of symbols. Two different speeds and two different color conditions were investigated. Robust early visual and P300 components were elicited time-locked to the presentation of the target. Offline classification revealed a mean accuracy of up to 90% for selecting the correct symbol out of 30 possibilities. The results suggest that RSVP-BCI is a promising new paradigm, also for patients with oculomotor impairments.

  9. Environmental Application of Reporter-Genes Based Biosensors for Chemical Contamination Screening

    Directory of Open Access Journals (Sweden)

    Matejczyk Marzena

    2014-12-01

    Full Text Available The paper presents results of research concerning possibilities of applications of reporter-genes based microorganisms, including the selective presentation of defects and advantages of different new scientific achievements of methodical solutions in genetic system constructions of biosensing elements for environmental research. The most robust and popular genetic fusion and new trends in reporter genes technology – such as LacZ (β-galactosidase, xylE (catechol 2,3-dioxygenase, gfp (green fluorescent proteins and its mutated forms, lux (prokaryotic luciferase, luc (eukaryotic luciferase, phoA (alkaline phosphatase, gusA and gurA (β-glucuronidase, antibiotics and heavy metals resistance are described. Reporter-genes based biosensors with use of genetically modified bacteria and yeast successfully work for genotoxicity, bioavailability and oxidative stress assessment for detection and monitoring of toxic compounds in drinking water and different environmental samples, surface water, soil, sediments.

  10. Enzyme-based solutions for textile processing and dye contaminant biodegradation-a review.

    Science.gov (United States)

    Chatha, Shahzad Ali Shahid; Asgher, Muhammad; Iqbal, Hafiz M N

    2017-06-01

    The textile industry, as recognized conformist and stake industry in the world's economy, is facing serious environmental challenges. In numerous industries, in practice, various chemical-based processes from initial sizing to final washing are fascinating harsh environment concerns. Some of these chemicals are corrosive to equipment and cause serious damage itself. Therefore, in the twenty-first century, chemical and allied industries quest a paradigm transition from traditional chemical-based concepts to a greener, sustainable, and environmentally friendlier catalytic alternative, both at the laboratory and industrial scales. Bio-based catalysis offers numerous benefits in the context of biotechnological industry and environmental applications. In recent years, bio-based processing has received particular interest among the scientist for inter- and multi-disciplinary investigations in the areas of natural and engineering sciences for the application in biotechnology sector at large and textile industries in particular. Different enzymatic processes such as chemical substitution have been developed or in the process of development for various textile wet processes. In this context, the present review article summarizes current developments and highlights those areas where environment-friendly enzymatic textile processing might play an increasingly important role in the textile industry. In the first part of the review, a special focus has been given to a comparative discussion of the chemical-based "classical/conventional" treatments and the modern enzyme-based treatment processes. Some relevant information is also reported to identify the major research gaps to be worked out in future.

  11. Mortality study of civilian employees exposed to contaminated drinking water at USMC Base Camp Lejeune: a retrospective cohort study

    Science.gov (United States)

    2014-01-01

    Background Two drinking water systems at U.S. Marine Corps Base Camp Lejeune, North Carolina were contaminated with solvents during 1950s-1985. Methods We conducted a retrospective cohort mortality study of 4,647 civilian, full-time workers employed at Camp Lejeune during 1973–1985 and potentially exposed to contaminated drinking water. We selected a comparison cohort of 4,690 Camp Pendleton workers employed during 1973–1985 and unexposed to contaminated drinking water. Mortality follow-up period was 1979-2008. Cause-specific standardized mortality ratios utilized U.S. age-, sex-, race-, and calendar period-specific mortality rates as reference. We used survival analysis to compare mortality rates between Camp Lejeune and Camp Pendleton workers and assess the effects of estimated cumulative contaminant exposures within the Camp Lejeune cohort. Ground water contaminant fate/transport and distribution system models provided monthly estimated contaminant levels in drinking water serving workplaces at Camp Lejeune. The confidence interval (CI) indicated precision of effect estimates. Results Compared to Camp Pendleton, Camp Lejeune workers had mortality hazard ratios (HRs) >1.50 for kidney cancer (HR = 1.92, 95% CI: 0.58, 6.34), leukemias (HR = 1.59, 95% CI: 0.66, 3.84), multiple myeloma (HR = 1.84, 95% CI: 0.45, 7.58), rectal cancer (HR = 1.65, 95% CI: 0.36, 7.44), oral cavity cancers (HR = 1.93, 95% CI: 0.34, 10.81), and Parkinson’s disease (HR = 3.13, 95% CI: 0.76, 12.81). Within the Camp Lejeune cohort, monotonic exposure-response relationships were observed for leukemia and vinyl chloride and PCE, with mortality HRs at the high exposure category of 1.72 (95% CI: 0.33, 8.83) and 1.82 (95% CI: 0.36, 9.32), respectively. Cumulative exposures were above the median for most deaths from cancers of the kidney, esophagus, rectum, prostate, and Parkinson’s disease, but small numbers precluded evaluation of exposure-response relationships. Conclusion The study found

  12. WebPresent: a World Wide Web-based telepresentation tool for physicians

    Science.gov (United States)

    Sampath-Kumar, Srihari; Banerjea, Anindo; Moshfeghi, Mehran

    1997-05-01

    In this paper, we present the design architecture and the implementation status of WebPresent - a world wide web based tele-presentation tool. This tool allows a physician to use a conference server workstation and make a presentation of patient cases to a geographically distributed audience. The audience consists of other physicians collaborating on patients' health care management and physicians participating in continuing medical education. These physicians are at several locations with networks of different bandwidth and capabilities connecting them. Audiences also receive the patient case information on different computers ranging form high-end display workstations to laptops with low-resolution displays. WebPresent is a scalable networked multimedia tool which supports the presentation of hypertext, images, audio, video, and a white-board to remote physicians with hospital Intranet access. WebPresent allows the audience to receive customized information. The data received can differ in resolution and bandwidth, depending on the availability of resources such as display resolution and network bandwidth.

  13. BOLDSync: a MATLAB-based toolbox for synchronized stimulus presentation in functional MRI.

    Science.gov (United States)

    Joshi, Jitesh; Saharan, Sumiti; Mandal, Pravat K

    2014-02-15

    Precise and synchronized presentation of paradigm stimuli in functional magnetic resonance imaging (fMRI) is central to obtaining accurate information about brain regions involved in a specific task. In this manuscript, we present a new MATLAB-based toolbox, BOLDSync, for synchronized stimulus presentation in fMRI. BOLDSync provides a user friendly platform for design and presentation of visual, audio, as well as multimodal audio-visual (AV) stimuli in functional imaging experiments. We present simulation experiments that demonstrate the millisecond synchronization accuracy of BOLDSync, and also illustrate the functionalities of BOLDSync through application to an AV fMRI study. BOLDSync gains an advantage over other available proprietary and open-source toolboxes by offering a user friendly and accessible interface that affords both precision in stimulus presentation and versatility across various types of stimulus designs and system setups. BOLDSync is a reliable, efficient, and versatile solution for synchronized stimulus presentation in fMRI study. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Probing Contaminant-Induced Alterations in Chlorophyll Fluorescence by AC-Dielectrophoresis-Based 2D-Algal Array

    Directory of Open Access Journals (Sweden)

    Coralie Siebman

    2018-02-01

    Full Text Available The investigation of contaminant impact on algae requires rapid and reliable cell collection and optical detection. The capability of alternative current (AC dielectrophoresis (DEP collection of whole cell arrays with combined fluorescence microscopy detection to follow the alterations of chlorophyll fluorescence during environmental contaminant exposure was explored. The application of an AC-field of 100 V cm−1, 100 Hz for 30 min to capture and immobilize the cells of green alga Chlamydomonas reinhardtii in two-dimensional (2D arrays does not induce changes in chlorophyll fluorescence. The results demonstrate that DEP-based 2D-arrays allow non-invasive detection of chlorophyll fluorescence change upon exposure to high concentrations of copper oxide nanoparticles and ionic copper. These results were in agreement with data obtained by flow cytometry used as a comparative method. The tool was also applied to follow the effect of a number of ubiquitous contaminants such as inorganic mercury, methylmercury, and diuron. However, a statistically significant short-term effect was observed only for mercury. Overall, DEP-based 2D-arrays of algal cells with fluorescence detection appear to be suitable for stain-free probing the effects on the photosynthetic microorganisms in highly polluted environment.

  15. Nanomaterial based detection and degradation of biological and chemical contaminants in a microfluidic system

    Science.gov (United States)

    Jayamohan, Harikrishnan

    Monitoring and remediation of environmental contaminants (biological and chemical) form the crux of global water resource management. There is an extant need to develop point-of-use, low-power, low-cost tools that can address this problem effectively with minimal environmental impact. Nanotechnology and microfluidics have made enormous advances during the past decade in the area of biosensing and environmental remediation. The "marriage" of these two technologies can effectively address some of the above-mentioned needs. In this dissertation, nanomaterials were used in conjunction with microfluidic techniques to detect and degrade biological and chemical pollutants. In the first project, a point-of-use sensor was developed for detection of trichloroethylene (TCE) from water. A self-organizing nanotubular titanium dioxide (TNA) synthesized by electrochemical anodization and functionalized with photocatalytically deposited platinum (Pt/TNA) was applied to the detection. The morphology and crystallinity of the Pt/TNA sensor was characterized using field emission scanning electron microscope, energy dis- persive x-ray spectroscopy, and X-ray diffraction. The sensor could detect TCE in the concentrations ranging from 10 to 1000 ppm. The room-temperature operation capability of the sensor makes it less power intensive and can potentially be incorporated into a field-based sensor. In the second part, TNA synthesized on a foil was incorporated into a flow-based microfluidic format and applied to degradation of a model pollutant, methylene blue. The system was demonstrated to have enhanced photocatalytic performance at higher flow rates (50-200 muL/min) over the same microfluidic format with TiO2 nanoparticulate (commercial P25) catalyst. The microfluidic format with TNA catalyst was able to achieve 82% fractional conversion of 18 mM methylene blue in comparison to 55% in the case of the TiO2 nanoparticulate layer at a flow rate of 200 L/min. The microfluidic device was

  16. Present status of accelerator-based BNCT: Focus on developments in Argentina

    International Nuclear Information System (INIS)

    Cartelli, D.; Capoulat, M.E.; Bergueiro, J.; Gagetti, L.; Suárez Anzorena, M.; Grosso, M.F. del; Baldo, M.; Castell, W.; Padulo, J.; Suárez Sandín, J.C.; Igarzabal, M.; Erhardt, J.; Mercuri, D.

    2015-01-01

    In this work we provide some information on the present status of accelerator-based BNCT (AB-BNCT) worldwide and subsequently concentrate on the recent accelerator technology developments in Argentina. - Highlights: • The current status of projects and associated facilities for AB-BNCT worldwide is shown. • Only low (few MeV) energy accelerators are included. • The recent progress of the Argentine AB-BNCT program is described.

  17. Analyses of integrated aircraft cabin contaminant monitoring network based on Kalman consensus filter.

    Science.gov (United States)

    Wang, Rui; Li, Yanxiao; Sun, Hui; Chen, Zengqiang

    2017-11-01

    The modern civil aircrafts use air ventilation pressurized cabins subject to the limited space. In order to monitor multiple contaminants and overcome the hypersensitivity of the single sensor, the paper constructs an output correction integrated sensor configuration using sensors with different measurement theories after comparing to other two different configurations. This proposed configuration works as a node in the contaminant distributed wireless sensor monitoring network. The corresponding measurement error models of integrated sensors are also proposed by using the Kalman consensus filter to estimate states and conduct data fusion in order to regulate the single sensor measurement results. The paper develops the sufficient proof of the Kalman consensus filter stability when considering the system and the observation noises and compares the mean estimation and the mean consensus errors between Kalman consensus filter and local Kalman filter. The numerical example analyses show the effectiveness of the algorithm. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Evaluation of surface contamination based on certifiably traceable, internationally accreditable measurements

    International Nuclear Information System (INIS)

    Whitlock, G.D.

    1992-01-01

    National Accreditation and Measurement Service (NAMAS) adopted by the EUROMET agreement requires that the calibration of monitoring instruments be traceable internationally with the objective that radiation hazard assessment be improved. This objective is achieved for Tritium surface contamination by employing calibration sources and evaluation methods which comply with ISO standards including the measurement of activity removable by Volatilization as well as dust. Consideration should be given to organic binding of tritium in the skin with its implications in the event of litigation. (author)

  19. [The historical background and present development of evidence-based healthcare and clinical nursing].

    Science.gov (United States)

    Tsai, Jung-Mei

    2014-12-01

    Evidence-based healthcare (EBHC) emphasizes the integration of the best research evidence with patient values, specialist suggestions, and clinical circumstances during the process of clinical decision-making. EBHC is a recognized core competency in modern healthcare. Nursing is a professional discipline of empirical science that thrives in an environment marked by advances in knowledge and technology in medicine as well as in nursing. Clinical nurses must elevate their skills and professional qualifications, provide efficient and quality health services, and promote their proficiency in EBHC. The Institute of Medicine in the United States indicates that evidence-based research results often fail to disseminate efficiently to clinical decision makers. This problem highlights the importance of better promoting the evidence-based healthcare fundamentals and competencies to frontline clinical nurses. This article describes the historical background and present development of evidence-based healthcare from the perspective of modern clinical nursing in light of the importance of evidence-based healthcare in clinical nursing; describes the factors associated with evidence-based healthcare promotion; and suggests strategies and policies that may improve the promotion and application of EBHC in clinical settings. The authors hope that this paper provides a reference for efforts to improve clinical nursing in the realms of EBHC training, promotion, and application.

  20. Clinical presentation of intraocular retinoblastoma; 5-year hospital-based registry in Egypt

    International Nuclear Information System (INIS)

    El Zomor, H.; Nour, R.; Alieldin, A.; Taha, H.; Montasr, M.M.; Moussa, E.; El Nadi, E.; Alfaar, A.S.; Alfaar, A.S.; El Zomor, H.; Taha, H.; Alieldin, A.; Montasr, M.M.; Moussa, E.; El Nadi, E.; Ezzat, S.

    2015-01-01

    Purpose: To study the presenting signs of Retinoblastoma in Egypt at Egypt’s main pediatric oncology referral center. Methods: This is a prospective descriptive study (hospital-based registry) conducted at Children’s Cancer Hospital Egypt between July 2007 and December 2012. Results: Out of 262 patients diagnosed with retinoblastoma, 244 were suffering from intra-ocular disease at presentation. One hundred thirty-nine (57%) patients presented with unilateral disease, while 105 (43%) suffered bilateral disease. The mean age at presentation was 20.6 ± 17 months, averaging 18.87 ± 11.76 months for bilateral and 25.72 ± 18.78 months for unilateral disease. The most common clinical presentation was leukocoria in 180 (73.8%) patients, strabismus in 32 (13.1%) patients and decreased visual acuity in 12 (4.9%) patients. Group D and E disease represented 62% of all affected eyes. Patients with advanced disease (Group C–E) had longer duration of symptoms.Conclusion: In Egypt, retinoblastoma patients present more frequently with advanced disease. There is an ever-increasing need to develop a national team dedicated to studying disease significance and formulating a national awareness program.

  1. Biofilm formation and antimicrobial sensitivity of lactobacilli contaminants from sugarcane-based fuel ethanol fermentation.

    Science.gov (United States)

    Dellias, Marina de Toledo Ferraz; Borges, Clóvis Daniel; Lopes, Mário Lúcio; da Cruz, Sandra Helena; de Amorim, Henrique Vianna; Tsai, Siu Mui

    2018-02-24

    Industrial ethanol fermentation is subject to bacterial contamination that causes significant economic losses in ethanol fuel plants. Chronic contamination has been associated with biofilms that are normally more resistant to antimicrobials and cleaning efforts than planktonic cells. In this study, contaminant species of Lactobacillus isolated from biofilms (source of sessile cells) and wine (source of planktonic cells) from industrial and pilot-scale fermentations were compared regarding their ability to form biofilms and their sensitivity to different antimicrobials. Fifty lactobacilli were isolated and the most abundant species were Lactobacillus casei, Lactobacillus fermentum and Lactobacillus plantarum. The majority of the isolates (87.8%) were able to produce biofilms in pure culture. The capability to form biofilms and sensitivity to virginiamycin, monensin and beta-acids from hops, showed inter- and intra-specific variability. In the pilot-scale fermentation, Lactobacillus brevis, L. casei and the majority of L. plantarum isolates were less sensitive to beta-acids than their counterparts from wine; L. brevis isolates from biofilms were also less sensitive to monensin when compared to the wine isolates. Biofilm formation and sensitivity to beta-acids showed a positive and negative correlation for L. casei and L. plantarum, respectively.

  2. Skull Base Osteomyelitis from Otitis Media Presenting as the Collet-Sicard Syndrome

    Directory of Open Access Journals (Sweden)

    Wong-Kein Low

    2018-01-01

    Full Text Available Skull base osteomyelitis can involve the jugular foramen and its associated cranial nerves resulting in specific clinical syndromes. The Collet-Sicard syndrome describes the clinical manifestations of palsies involving cranial nerves IX, X, XI, and XII. We present a rare atypical case of skull base osteomyelitis originating from infection of the middle ear and causing the Collet-Sicard syndrome. Caused by Pseudomonas aeruginosa and Klebsiella pneumoniae, this occurred in an elderly diabetic man subsequent to retention of a cotton swab in an ear with chronic suppurative otitis media. This case report illustrates the possibility of retained cotton swabs contributing to the development of otitis media, skull base osteomyelitis, and ultimately the Collet-Sicard syndrome in the ears of immune-compromised patients with chronically perforated eardrums.

  3. Pheromone-Based Pest Management in China: Past, Present, and Future Prospects.

    Science.gov (United States)

    Cui, Gen Zhong; Zhu, Junwei Jerry

    2016-07-01

    Semiochemical-based pest management technology has been widely used to monitor and control insect pests in agricultural, forestry, and public health sectors in the western world. It became a popular tool in the early 1970s with tremendous efforts in developing environment-friendly control technologies for the integrated pest management. However, in China, similar research lagged 15 to 20 years and was not initiated until the late 1980s. In this review, we present the early history of pheromone research that has led to the current practical applications in China, particularly in the development of pheromone-based pest management products. We also provide information regarding the current status of pheromone-based product manufacturing, marketing, and regulatory issues related to local semiochemical industries, which may be useful to other international companies interested in pursuing business in China. In addition, we share some research topics that represent new directions of the present pheromone research to explore novel tools for advancing semiochemical-based pest management in China.

  4. Present state and future of CFD based on three-dimensional RANS analysis

    International Nuclear Information System (INIS)

    Kim, Kwang Yong

    2004-01-01

    Computational Fluid Dynamics (CFD) based on Navier-Stokes equations has been developed rapidly for several decades with the developments of high speed computers and numerical algorithms, and presently is regarded as an essential analysis tool in the engineering applications containing fluid flow and convective heat transfer. It is known that for turbulent flow the Navier-Stokes equations can be calculated precisely by Direct Numerical Simulation (DNS). However, DNS needs huge computing time even for simple low-Reynolds number flows, and thus is not practical. Large Eddy Simulation (LES) can be an alternative. But, LES also needs considerable computing time for the analysis of engineering flows, and have some problem in the methods. Therefore, the analysis methods using Reynolds-averaged Navier-stokes equations (RANS) and turbulence closure models are still regarded as the major techniques for the analysis of turbulent flows in spite of the inaccuracy of the prediction. In this presentation, the present state and the prospect of CFD based on three-dimensional RANS analysis are introduced for physical models and numerical algorithms with the engineering examples. Especially, for the analysis of two-phase flows in nuclear reactor, the recently developed techniques are also introduced. And, the presentation includes the methods of design optimization using RANS analysis and numerical optimization techniques with variety of the applications

  5. Spectral imaging for contamination detection in food

    DEFF Research Database (Denmark)

    Carstensen, Jens Michael

    application of the technique is finding anomalies I supposedly homogeneous matter or homogeneous mixtures. This application occurs frequently in the food industry when different types of contamination are to be detected. Contaminants could be e.g. foreign matter, process-induced toxins, and microbiological...... spoilage. Many of these contaminants may be detected in the wavelength range visible to normal silicium-based camera sensors i.e. 350-1050 nm with proper care during sample preparation, sample presentation, image acquisition and analysis. This presentation will give an introduction to the techniques behind...

  6. Plasma-based water treatment: development of a general mechanistic model to estimate the treatability of different types of contaminants

    International Nuclear Information System (INIS)

    Mededovic Thagard, Selma; Stratton, Gunnar R; Paek, Eunsu; Dai, Fei; Holsen, Thomas M; Bellona, Christopher L; Bohl, Douglas G; Dickenson, Eric R V

    2017-01-01

    To determine the types of applications for which plasma-based water treatment (PWT) is best suited, the treatability of 23 environmental contaminants was assessed through treatment in a gas discharge reactor with argon bubbling, termed the enhanced-contact reactor. The contaminants were treated in a mixture to normalize reaction conditions and convective transport limitations. Treatability was compared in terms of the observed removal rate constant ( k obs ). To characterize the influence of interfacial processes on k obs , a model was developed that accurately predicts k obs for each compound, as well as the contributions to k obs from each of the three general degradation mechanisms thought to occur at or near the gas–liquid interface: ‘sub-surface’, ‘surface’ and ‘above-surface’. Sub-surface reactions occur just underneath the gas–liquid interface between the contaminants and dissolved plasma-generated radicals, contributing significantly to the removal of compounds that lack surfactant-like properties and so are not highly concentrated at the interface. Surface reactions occur at the interface between the contaminants and dissolved radicals, contributing significantly to the removal of surfactant-like compounds that have high interfacial concentrations. The contaminants’ interfacial concentrations were calculated using surface-activity parameters determined through surface tension measurements. Above-surface reactions are proposed to take place in the plasma interior between highly energetic plasma species and exposed portions of compounds that extend out of the interface. This mechanism largely accounts for the degradation of surfactant-like contaminants that contain highly hydrophobic perfluorocarbon groups, which are most likely to protrude from the interface. For a few compounds, the degree of exposure to the plasma interior was supported by new and previously reported molecular dynamics simulations results. By reviewing the predicted

  7. Plasma-based water treatment: development of a general mechanistic model to estimate the treatability of different types of contaminants

    Science.gov (United States)

    Mededovic Thagard, Selma; Stratton, Gunnar R.; Dai, Fei; Bellona, Christopher L.; Holsen, Thomas M.; Bohl, Douglas G.; Paek, Eunsu; Dickenson, Eric R. V.

    2017-01-01

    To determine the types of applications for which plasma-based water treatment (PWT) is best suited, the treatability of 23 environmental contaminants was assessed through treatment in a gas discharge reactor with argon bubbling, termed the enhanced-contact reactor. The contaminants were treated in a mixture to normalize reaction conditions and convective transport limitations. Treatability was compared in terms of the observed removal rate constant (k obs). To characterize the influence of interfacial processes on k obs, a model was developed that accurately predicts k obs for each compound, as well as the contributions to k obs from each of the three general degradation mechanisms thought to occur at or near the gas-liquid interface: ‘sub-surface’, ‘surface’ and ‘above-surface’. Sub-surface reactions occur just underneath the gas-liquid interface between the contaminants and dissolved plasma-generated radicals, contributing significantly to the removal of compounds that lack surfactant-like properties and so are not highly concentrated at the interface. Surface reactions occur at the interface between the contaminants and dissolved radicals, contributing significantly to the removal of surfactant-like compounds that have high interfacial concentrations. The contaminants’ interfacial concentrations were calculated using surface-activity parameters determined through surface tension measurements. Above-surface reactions are proposed to take place in the plasma interior between highly energetic plasma species and exposed portions of compounds that extend out of the interface. This mechanism largely accounts for the degradation of surfactant-like contaminants that contain highly hydrophobic perfluorocarbon groups, which are most likely to protrude from the interface. For a few compounds, the degree of exposure to the plasma interior was supported by new and previously reported molecular dynamics simulations results. By reviewing the predicted

  8. Modern, PC based, high resolution portable EDXRF analyzer offers laboratory performance for field, in-situ analysis of environmental contaminants

    International Nuclear Information System (INIS)

    Piorek, Stanislaw

    1994-01-01

    The introduction of a new, high resolution, portable probe that has improved the sensitivity of the conventional field portable X-ray fluorescence (FPXRF) by up to an order of magnitude had been reported earlier [S. Piorek and J.R. Pasmore, Proc. 2nd Int. Symp. on Field Screening Methods for Hazardous Wastes and Toxic Chemicals, Las Vegas, 1991, p. 737]. A high resolution Si(Li) detector probe operates connected to a multichannel X-ray analyzer (2048 channels) which is housed in a portable, battery powered industrial computer. An improved energy resolution of the detector allows the implementation of more sophisticated data treatment methods to convert the measured intensities into mass concentrations of the analytes. A backscatter with a fundamental parameters approach (BFP) is one of the best methods, specifically for metallic contaminants in soil. A program has been written based on the BFP method for use with the new probe. The new software/probe combination enables one to quickly assess levels of contaminants on the site without the need of analyzed samples for instrument calibration. The performance of the EDXRF system in application to analysis of metals in contaminated soil is discussed in this paper. Also discussed is the extension of this method in the analysis of other types of environmental samples such as air particulates collected on filter paper. ((orig.))

  9. Does parent-child agreement vary based on presenting problems? Results from a UK clinical sample.

    Science.gov (United States)

    Cleridou, Kalia; Patalay, Praveetha; Martin, Peter

    2017-01-01

    Discrepancies are often found between child and parent reports of child psychopathology, nevertheless the role of the child's presenting difficulties in relation to these is underexplored. This study investigates whether parent-child agreement on the conduct and emotional scales of the Strengths and Difficulties Questionnaire (SDQ) varied as a result of certain child characteristics, including the child's presenting problems to clinical services, age and gender. The UK-based sample consisted of 16,754 clinical records of children aged 11-17, the majority of which were female (57%) and White (76%). The dataset was provided by the Child Outcomes Research Consortium , which collects outcome measures from child services across the UK. Clinicians reported the child's presenting difficulties, and parents and children completed the SDQ. Using correlation analysis, the main findings indicated that agreement varied as a result of the child's difficulties for reports of conduct problems, and this seemed to be related to the presence or absence of externalising difficulties in the child's presentation. This was not the case for reports of emotional difficulties. In addition, agreement was higher when reporting problems not consistent with the child's presentation; for instance, agreement on conduct problems was greater for children presenting with internalising problems. Lastly, the children's age and gender did not seem to have an impact on agreement. These findings demonstrate that certain child presenting difficulties, and in particular conduct problems, may be related to informant agreement and need to be considered in clinical practice and research. Trial Registration This study was observational and as such did not require trial registration.

  10. Multirapid Serial Visual Presentation Framework for EEG-Based Target Detection

    Directory of Open Access Journals (Sweden)

    Zhimin Lin

    2017-01-01

    Full Text Available Target image detection based on a rapid serial visual presentation (RSVP paradigm is a typical brain-computer interface system with various applications, such as image retrieval. In an RSVP paradigm, a P300 component is detected to determine target images. This strategy requires high-precision single-trial P300 detection methods. However, the performance of single-trial detection methods is relatively lower than that of multitrial P300 detection methods. Image retrieval based on multitrial P300 is a new research direction. In this paper, we propose a triple-RSVP paradigm with three images being presented simultaneously and a target image appearing three times. Thus, multitrial P300 classification methods can be used to improve detection accuracy. In this study, these mechanisms were extended and validated, and the characteristics of the multi-RSVP framework were further explored. Two different P300 detection algorithms were also utilized in multi-RSVP to demonstrate that the scheme is universally applicable. Results revealed that the detection accuracy of the multi-RSVP paradigm was higher than that of the standard RSVP paradigm. The results validate the effectiveness of the proposed method, and this method can provide a whole new idea in the field of EEG-based target detection.

  11. GIS - Based data presentation and interactive communication system for public involvement in EIA

    International Nuclear Information System (INIS)

    Oprea, I.; Oprea, M.; Guta, V.; Pirvu, V.

    2001-01-01

    The data presentation and interactive communication system has as main task to integrate technical and administrative information, as well as to ensure an efficient public participation. The system can achieve desired inter-operability between specialists, government and public in decision-making and environmental impact assessment (EIA). It incorporates different modules relative to specific types of parameters and authorities involved. The GIS-based system provides mapping, database, automatic information collection and advanced presentation techniques. It includes a graphically oriented executive support, which has the ability to present information by geographical representation of the zones on the map. The public opinion is taking into account by consideration of alternatives and providing access to the monitoring of environmental effects. The system offers an effective way to avoid negative reactions by interactive communication based on real-time information exchange. The system can be integrated into national or international management systems, being a useful tool for an efficient communication, handling and exchanging a vast amount of information. (authors)

  12. Simultaneous removal of selected oxidized contaminants in groundwater using a continuously stirred hydrogen-based membrane biofilm reactor.

    Science.gov (United States)

    Xia, Siqing; Liang, Jun; Xu, Xiaoyin; Shen, Shuang

    2013-01-01

    A laboratory trial was conducted for evaluating the capability of a continuously stirred hydrogen-based membrane biofilm reactor to simultaneously reduce nitrate (NO(3-)-N), sulfate (SO4(2-)), bromate (BrO3-), hexavalent chromium (Cr(VI)) and parachloronitrobenzene (p-CNB). The reactor contained two bundles of hollow fiber membranes functioning as an autotrophic biofilm carrier and hydrogen pipe as well. On the condition that hydrogen was supplied as electron donor and diffused into water through membrane pores, autohydrogenotrophic bacteria were capable of reducing contaminants to forms with lower toxicity. Reduction occurred within 1 day and removal fluxes for NO(3-)-N, SO4(2-), BrO3-, Cr(VI), and p-CNB reached 0.641, 2.396, 0.008, 0.016 and 0.031 g/(day x m2), respectively after 112 days of continuous operation. Except for the fact that sulfate was 37% removed under high surface loading, the other four contaminants were reduced by over 95%. The removal flux comparison between phases varying in surface loading and H2 pressure showed that decreasing surface loading or increasing H2 pressure would promote removal flux. Competition for electrons occurred among the five contaminants. Electron-equivalent flux analysis showed that the amount of utilized hydrogen was mainly controlled by NO(3-)-N and SO4(2-) reduction, which accounted for over 99% of the electron flux altogether. It also indicated the electron acceptor order, showing that nitrate was the most prior electron acceptor while suIfate was the second of the five contaminants.

  13. Developing Sediment Remediation Goals at Superfund Sites Based on Pore Water for the Protection of Benthic Organisms from Direct Toxicity to Non-ionic Organic Contaminants

    Science.gov (United States)

    A methodology for developing remediation goals for sites with contaminated sediments is provided. The remediation goals are based upon the concentrations of chemicals in the sediment interstitial water measured using the passive sampling technique. The passive sampling technique ...

  14. Contamination Analyzer

    Science.gov (United States)

    1994-01-01

    Measurement of the total organic carbon content in water is important in assessing contamination levels in high purity water for power generation, pharmaceutical production and electronics manufacture. Even trace levels of organic compounds can cause defects in manufactured products. The Sievers Model 800 Total Organic Carbon (TOC) Analyzer, based on technology developed for the Space Station, uses a strong chemical oxidizing agent and ultraviolet light to convert organic compounds in water to carbon dioxide. After ionizing the carbon dioxide, the amount of ions is determined by measuring the conductivity of the deionized water. The new technique is highly sensitive, does not require compressed gas, and maintenance is minimal.

  15. Assessment of heavy metal bioavailability in contaminated sediments and soils using green fluorescent protein-based bacterial biosensors

    International Nuclear Information System (INIS)

    Liao, V.H.-C.; Chien, M.-T.; Tseng, Y.-Y.; Ou, K.-L.

    2006-01-01

    A green fluorescent protein (GFP)-based bacterial biosensor Escherichia coli DH5α (pVLCD1) was developed based on the expression of gfp under the control of the cad promoter and the cadC gene of Staphylococcus aureus plasmid pI258. DH5α (pVLCD1) mainly responded to Cd(II), Pb(II), and Sb(III), the lowest detectable concentrations being 0.1 nmol L -1 , 10 nmol L -1 , and 0.1 nmol L -1 , respectively, with 2 h exposure. The biosensor was field-tested to measure the relative bioavailability of the heavy metals in contaminated sediments and soil samples. The results showed that the majority of heavy metals remained adsorbed to soil particles: Cd(II)/Pb(II) was only partially available to the biosensor in soil-water extracts. Our results demonstrate that the GFP-based bacterial biosensor is useful and applicable in determining the bioavailability of heavy metals with high sensitivity in contaminated sediment and soil samples and suggests a potential for its inexpensive application in environmentally relevant sample tests. - Nonpathogenic GFP-based bacterial biosensor is applicable in determining the bioavailability of heavy metals in environmental samples

  16. Texosome-based drug delivery system for cancer therapy: from past to present

    International Nuclear Information System (INIS)

    Mahmoodzadeh Hosseini, Hamideh; Halabian, Raheleh; Amin, Mohsen; Imani Fooladi, Abbas Ali

    2015-01-01

    Rising worldwide cancer incidence and resistance to current anti-cancer drugs necessitate the need for new pharmaceutical compounds and drug delivery system. Malfunction of the immune system, particularly in the tumor microenvironment, causes tumor growth and enhances tumor progression. Thus, cancer immunotherapy can be an appropriate approach to provoke the systemic immune system to combat tumor expansion. Texosomes, which are endogenous nanovesicles released by all tumor cells, contribute to cell-cell communication and modify the phenotypic features of recipient cells due to the texosomes’ ability to transport biological components. For this reason, texosome-based delivery system can be a valuable strategy for therapeutic purposes. To improve the pharmaceutical behavior of this system and to facilitate its use in medical applications, biotechnology approaches and mimetic techniques have been utilized. In this review, we present the development history of texosome-based delivery systems and discuss the advantages and disadvantages of each system

  17. Present and next steps of the JAERI superconducting rf linac based FEL program

    International Nuclear Information System (INIS)

    Minehara, E.J.; Yamauchi, T.; Sugimoto, M.

    2000-01-01

    The JAERI superconducting rf linac based FEL has successfully been lased to produce a 0.3 kW FEL light and 100 kW or larger electron beam output in quasi continuous wave operation in 1999. The 1 kW class output as our present program goal will be achieved to improve the optical out coupling method in the FEL optical resonator, the electron gun, and the electron beam optics in the JAERI FEL driver. As our next 5 year program goal is the 100 kW class FEL light and a few tens MW class electron beam output in average, quasi continuous wave operation of the light and electron beam will be planned in the JAERI superconducting rf linac based FEL facility. Conceptual design options needed for such a very high power operation and shorter wavelength light sources will be discussed to improve and to upgrade the exciting facility. (author)

  18. Thermogravimetric study of reduction of oxides present in oxidized nickel-base alloy powders

    Science.gov (United States)

    Herbell, T. P.

    1976-01-01

    Carbon, hydrogen, and hydrogen plus carbon reduction of three oxidized nickel-base alloy powders (a solid solution strengthened alloy both with and without the gamma prime formers aluminum and titanium and the solid solution strengthened alloy NiCrAlY) were evaluated by thermogravimetry. Hydrogen and hydrogen plus carbon were completely effective in reducing an alloy containing chromium, columbium, tantalum, molybdenum, and tungsten. However, with aluminum and titanium present the reduction was limited to a weight loss of about 81 percent. Carbon alone was not effective in reducing any of the alloys, and none of the reducing conditions were effective for use with NiCrAlY.

  19. Contamination Control for Thermal Engineers

    Science.gov (United States)

    Rivera, Rachel B.

    2015-01-01

    The presentation will be given at the 26th Annual Thermal Fluids Analysis Workshop (TFAWS 2015) hosted by the Goddard Spaceflight Center (GSFC) Thermal Engineering Branch (Code 545). This course will cover the basics of Contamination Control, including contamination control related failures, the effects of contamination on Flight Hardware, what contamination requirements translate to, design methodology, and implementing contamination control into Integration, Testing and Launch.

  20. Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

    International Nuclear Information System (INIS)

    Sevigny, J.H.; Lintott, D.; Wrubleski, R.M.; Drury, C.R.

    1997-01-01

    The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox R toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox R toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox R toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent

  1. Immobilization of metals in contaminated soils using natural polymer-based stabilizers.

    Science.gov (United States)

    Tao, Xue; Li, Aimin; Yang, Hu

    2017-03-01

    Three low-cost natural polymer materials, namely, lignin (Ln), carboxymethyl cellulose, and sodium alginate, were used for soil amendment to immobilize lead and cadmium in two contaminated soil samples collected from a mining area in Nanjing, China. The remediation effects of the aforementioned natural polymers were evaluated by toxicity characteristic leaching procedure (TCLP) and sequential extractions. The stabilizers could lower the bioavailability of Pb and Cd in the contaminated soils, and the amount of the exchangeable forms of the aforementioned two metals were reduced evidently. TCLP results showed that the leaching concentrations of Pb and Cd were decreased by 5.46%-71.1% and 4.25%-49.6%, respectively, in the treated soils. The contents of the organic forms of the two metals both increased with the increase in stabilizer dose on the basis of the redistribution of metal forms by sequential extractions. These findings were due to the fact that the abundant oxygen-containing groups on the polymeric amendments were effective in chelating and immobilizing Pb and Cd, which have been further confirmed from the metal adsorptions in aqueous solutions. Moreover, Ln achieved the greatest effect among the three polymers under study because of the former's distinct three-dimensional molecular structure, showing the preferential immobilization of Pb over Cd in soils also. Thus, the above-mentioned natural polymers hold great application potentials for reducing metal ion entry into the food chain at a field scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Sevigny, J.H. [Komex Consultants Ltd., Calgary, AB (Canada); Lintott, D. [HydroQual Consultants, Inc., Calgary, AB (Canada); Wrubleski, R.M.; Drury, C.R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre

    1997-12-31

    The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox{sup R} toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox{sup R} toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox{sup R} toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent.

  3. StressPhone: smartphone based platform for measurement of cortisol for stress detection (Conference Presentation)

    Science.gov (United States)

    Jain, Aadhar; Rey, Elizabeth; Lee, Seoho; O'Dell, Dakota; Erickson, David

    2016-03-01

    Anxiety disorders are estimated to be the most common mental illness in US affecting around 40 million people and related job stress is estimated to cost US industry up to $300 billion due to lower productivity and absenteeism. A personal diagnostic device which could help identify stressed individuals would therefore be a huge boost for workforce productivity. We are therefore developing a point of care diagnostic device that can be integrated with smartphones or tablets for the measurement of cortisol - a stress related salivary biomarker, which is known to be strongly involved in body's fight-or-flight response to a stressor (physical or mental). The device is based around a competitive lateral flow assay whose results can then be read and quantified through an accessory compatible with the smartphone. In this presentation, we report the development and results of such an assay and the integrated device. We then present the results of a study relating the diurnal patterns of cortisol levels and the alertness of an individual based on the circadian rhythm and sleep patterns of the individual. We hope to use the insight provided by combining the information provided by levels of stress related to chemical biomarkers of the individual with the physical biomarkers to lead to a better informed and optimized activity schedule for maximized work output.

  4. Evaluation of anemia diagnosis based on elastic light scattering (Conference Presentation)

    Science.gov (United States)

    Tong, Lieshu; Wang, Xinrui; Xie, Dengling; Chen, Xiaoya; Chu, Kaiqin; Dou, Hu; Smith, Zachary J.

    2017-03-01

    Currently, one-third of humanity is still suffering from anemia. In China the most common forms of anemia are iron deficiency and Thalassemia minor. Differentiating these two is the key to effective treatment. Iron deficiency is caused by malnutrition and can be cured by iron supplementation. Thalassemia is a hereditary disease in which the hemoglobin β chain is lowered or absent. Iron therapy is not effective, and there is evidence that iron therapy may be harmful to patients with Thalassemia. Both anemias can be diagnosed using red blood cell morphology: Iron deficiency presents a smaller mean cell volume compared to normal cells, but with a wide distribution; Thalassemia, meanwhile, presents a very small cell size and tight particle size distribution. Several researchers have proposed diagnostic indices based on red cell morphology to differentiate these two diseases. However, these indices lack sensitivity and specificity and are constructed without statistical rigor. Using multivariate methods we demonstrate a new classification method based on red cell morphology that diagnoses anemia in a Chinese population with enough accuracy for its use as a screening method. We further demonstrate a low cost instrument that precisely measures red cell morphology using elastic light scattering. This instrument is combined with an automated analysis program that processes scattering data to report red cell morphology without the need for user intervention. Despite using consumer-grade components, when comparing our experimental results with gold-standard measurements, the device can still achieve the high precision required for sensing clinically significant changes in red cell morphology.

  5. Predicting arsenic and heavy metals contamination in groundwater resources of Ghahavand plain based on an artificial neural network optimized by imperialist competitive algorithm

    Directory of Open Access Journals (Sweden)

    Meysam Alizamir

    2017-10-01

    Full Text Available Background: The effects of trace elements on human health and the environment gives importance to the analysis of heavy metals contamination in environmental samples and, more particularly, human food sources. Therefore, the current study aimed to predict arsenic and heavy metals (Cu, Pb, and Zn contamination in the groundwater resources of Ghahavand Plain based on an artificial neural network (ANN optimized by imperialist competitive algorithm (ICA. Methods: This study presents a new method for predicting heavy metal concentrations in the groundwater resources of Ghahavand plain based on ANN and ICA. The developed approaches were trained using 75% of the data to obtain the optimum coefficients and then tested using 25% of the data. Two statistical indicators, the coefficient of determination (R2 and the root-mean-square error (RMSE, were employed to evaluate model performance. A comparison of the performances of the ICA-ANN and ANN models revealed the superiority of the new model. Results of this study demonstrate that heavy metal concentrations can be reliably predicted by applying the new approach. Results: Results from different statistical indicators during the training and validation periods indicate that the best performance can be obtained with the ANN-ICA model. Conclusion: This method can be employed effectively to predict heavy metal concentrations in the groundwater resources of Ghahavand plain.

  6. Using a tiered approach based on ecotoxicological techniques to assess the ecological risks of contamination in a subtropical estuarine protected area.

    Science.gov (United States)

    Campos, B G; Cruz, A C F; Buruaem, L M; Rodrigues, A P C; Machado, W T V; Abessa, D M S

    2016-02-15

    This study sought to assess the ecological risks of sediments from the northern portion of an estuarine protected area (Cananéia-Iguape-Peruíbe Protected Area--CIP-PA). The CIP-PA is located on the southern coast of São Paulo State, Brazil and is influenced by former mining activities along the Ribeira de Iguape River (RIR). We used a tiered approach based on multiple lines of evidence (geochemical analyses, toxicity tests, and whole sediment toxicity identification and evaluation) in order to assess environmental quality. The sediments presented a heterogeneous composition, but the samples collected close to the RIR exhibited higher concentrations of metals (Cd, Cr, Cu, Pb) and toxicity. Multivariate analysis showed that toxicity was associated with metals, mud, organic matter, and CaCO3 quantities. The whole-sediment toxicity identification evaluation approach indicated that ammonia and metals were responsible for sediment toxicity. Overall, we concluded that the sediments collected at depositional areas from the northern portion of the CIP-PA presented high levels of metals, which originated from former mining areas located in the upper RIR basin, and that this contamination had toxic effects on aquatic invertebrates. The tiered approach was useful for identifying the degradation of sediment quality and also for indicating the causes of toxicity. Because the CIP-PA is an important estuarine protected area that is ecologically at risk, large-scale measures are required to control the sources of contamination.

  7. Methodology for performing surveys for fixed contamination

    International Nuclear Information System (INIS)

    Durham, J.S.; Gardner, D.L.

    1994-10-01

    This report describes a methodology for performing instrument surveys for fixed contamination that can be used to support the release of material from radiological areas, including release to controlled areas and release from radiological control. The methodology, which is based on a fast scan survey and a series of statistical, fixed measurements, meets the requirements of the U.S. Department of Energy Radiological Control Manual (RadCon Manual) (DOE 1994) and DOE Order 5400.5 (DOE 1990) for surveys for fixed contamination and requires less time than a conventional scan survey. The confidence interval associated with the new methodology conforms to the draft national standard for surveys. The methodology that is presented applies only to surveys for fixed contamination. Surveys for removable contamination are not discussed, and the new methodology does not affect surveys for removable contamination

  8. Bioremediation of oil sludge contaminated soil using bulking agent mixture enriched consortia of microbial inoculants based by irradiated compost

    International Nuclear Information System (INIS)

    Tri Retno, D.L.; Mulyana, N.

    2013-01-01

    Bulking agent mixture enriched consortia of microbial inoculants based by irradiated compost was used on bioremediation of microcosm scale contaminated by hydrocarbon soil. Bioremediation composting was carried out for 42 days. Composting was done with a mixture of bulking agent (sawdust, residual sludge biogas and compost) by 30%, mud petroleum (oil sludge) by 20% and 50% of soil. Mixture of 80% soil and 20% oil sludge was used as a control. Irradiated compost was used as a carrier for consortia of microbial inoculants (F + B) which biodegradable hydrocarbons. Treatment variations include A1, A2, B1, B2, C1, C2, D1 and D2. Process parameters were observed to determine the optimal conditions include: temperature, pH, water content, TPC (Total Plate Count) and degradation of % TPH (Total Petroleum Hydrocarbon). Optimal conditions were achieved in the remediation of oil sludge contamination of 20% using the B2 treatment with the addition consortia of microbial inoculants based by irradiated compost of sawdust (bulking agentby 30% at concentrations of soil by 50% with TPH degradation optimal efficiency of 81.32%. The result of GC-MS analysis showed that bioremediation for 42 days by using a sawdust as a mixture of bulking agents which enriched consortia of microbial inoculants based by irradiated compost is biodegradeable, so initial hydrocarbons with the distribution of the carbon chain C-7 to C-54 into final hydrocarbons with the distribution of carbon chain C-6 to C-8. (author)

  9. Do morphometric parameters and geological conditions determine chemistry of glacier surface ice? Spatial distribution of contaminants present in the surface ice of Spitsbergen glaciers (European Arctic).

    Science.gov (United States)

    Lehmann, Sara; Gajek, Grzegorz; Chmiel, Stanisław; Polkowska, Żaneta

    2016-12-01

    The chemism of the glaciers is strongly determined by long-distance transport of chemical substances and their wet and dry deposition on the glacier surface. This paper concerns spatial distribution of metals, ions, and dissolved organic carbon, as well as the differentiation of physicochemical parameters (pH, electrical conductivity) determined in ice surface samples collected from four Arctic glaciers during the summer season in 2012. The studied glaciers represent three different morphological types: ground based (Blomlibreen and Scottbreen), tidewater which evolved to ground based (Renardbreen), and typical tidewater glacier (Recherchebreen). All of the glaciers are functioning as a glacial system and hence are subject to the same physical processes (melting, freezing) and the process of ice flowing resulting from the cross-impact force of gravity and topographic conditions. According to this hypothesis, the article discusses the correlation between morphometric parameters, changes in mass balance, geological characteristics of the glaciers and the spatial distribution of analytes on the surface of ice. A strong correlation (r = 0.63) is recorded between the aspect of glaciers and values of pH and ions, whereas dissolved organic carbon (DOC) depends on the minimum elevation of glaciers (r = 0.55) and most probably also on the development of the accumulation area. The obtained results suggest that although certain morphometric parameters largely determine the spatial distribution of analytes, also the geology of the bed of glaciers strongly affects the chemism of the surface ice of glaciers in the phase of strong recession.

  10. Images from the Mind: BCI image reconstruction based on Rapid Serial Visual Presentations of polygon primitives

    Directory of Open Access Journals (Sweden)

    Luís F Seoane

    2015-04-01

    Full Text Available We provide a proof of concept for an EEG-based reconstruction of a visual image which is on a user's mind. Our approach is based on the Rapid Serial Visual Presentation (RSVP of polygon primitives and Brain-Computer Interface (BCI technology. In an experimental setup, subjects were presented bursts of polygons: some of them contributed to building a target image (because they matched the shape and/or color of the target while some of them did not. The presentation of the contributing polygons triggered attention-related EEG patterns. These Event Related Potentials (ERPs could be determined using BCI classification and could be matched to the stimuli that elicited them. These stimuli (i.e. the ERP-correlated polygons were accumulated in the display until a satisfactory reconstruction of the target image was reached. As more polygons were accumulated, finer visual details were attained resulting in more challenging classification tasks. In our experiments, we observe an average classification accuracy of around 75%. An in-depth investigation suggests that many of the misclassifications were not misinterpretations of the BCI concerning the users' intent, but rather caused by ambiguous polygons that could contribute to reconstruct several different images. When we put our BCI-image reconstruction in perspective with other RSVP BCI paradigms, there is large room for improvement both in speed and accuracy. These results invite us to be optimistic. They open a plethora of possibilities to explore non-invasive BCIs for image reconstruction both in healthy and impaired subjects and, accordingly, suggest interesting recreational and clinical applications.

  11. Present status and future directions of the JAERI superconducting RF linac-based FEL

    International Nuclear Information System (INIS)

    Minehara, EJ.; Yamauchi, T.; Sugimori, M.; Sawamura, M.; Hajima, R.; Nagai, R.; Kikuzawa, N.; Nishimori, N.; Shizuma, T.

    2000-01-01

    The JAERI superconducting rf linac based FEL has successfully been lased to produce a 2.34kW FEL light and l00kW electron beam output in quasi continuous wave operation in February 2000. Twice larger output than the present program goal of 1kW was achieved to improve the optical out coupling method in the FEL optical resonator, the electron gun, and the electron beam optics in the JAERI FEL driver. As our next 2 years program goal is the 100kW class FEL light and a few MW class electron beam output in average, quasi continuous wave operation of the light and electron beam will be planned in the JAERI superconducting rf linac based FEL facility. Conceptual and engineering design options needed for such a very high power operation will be discussed to improve and to upgrade the existing facility. Finally, several applications, table-top superconducting rf linac based FELs, and an X-ray FEL R and D will be discussed as a next-five years program at JAERI-FEL laboratory. (author)

  12. Microcontroller based fibre-optic visual presentation system for multisensory neuroimaging.

    Science.gov (United States)

    Kurniawan, Veldri; Klemen, Jane; Chambers, Christopher D

    2011-10-30

    Presenting visual stimuli in physical 3D space during fMRI experiments carries significant technical challenges. Certain types of multisensory visuotactile experiments and visuomotor tasks require presentation of visual stimuli in peripersonal space, which cannot be accommodated by ordinary projection screens or binocular goggles. However, light points produced by a group of LEDs can be transmitted through fibre-optic cables and positioned anywhere inside the MRI scanner. Here we describe the design and implementation of a microcontroller-based programmable digital device for controlling fibre-optically transmitted LED lights from a PC. The main feature of this device is the ability to independently control the colour, brightness, and timing of each LED. Moreover, the device was designed in a modular and extensible way, which enables easy adaptation for various experimental paradigms. The device was tested and validated in three fMRI experiments involving basic visual perception, a simple colour discrimination task, and a blocked multisensory visuo-tactile task. The results revealed significant lateralized activation in occipital cortex of all participants, a reliable response in ventral occipital areas to colour stimuli elicited by the device, and strong activations in multisensory brain regions in the multisensory task. Overall, these findings confirm the suitability of this device for presenting complex fibre-optic visual and cross-modal stimuli inside the scanner. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Modification of Optical Properties of Seawater Exposed to Oil Contaminants Based on Excitation-Emission Spectra

    Science.gov (United States)

    Baszanowska, E.; Otremba, Z.

    2015-10-01

    The optical behaviour of seawater exposed to a residual amount of oil pollution is presented and a comparison of the fluorescence spectra of oil dissolved in both n-hexane and seawater is discussed based on excitation-emission spectra. Crude oil extracted from the southern part of the Baltic Sea was used to characterise petroleum properties after contact with seawater. The wavelength-independent fluorescence maximum for natural seawater and seawater artificially polluted with oil were determined. Moreover, the specific excitation-emission peaks for natural seawater and polluted water were analysed to identify the natural organic matter composition. It was found that fluorescence spectra identification is a promising method to detect even an extremely low concentration of petroleum residues directly in the seawater. In addition, alien substances disturbing the fluorescence signatures of natural organic substances in a marine environment is also discussed.

  14. Reconstruction of the external dose of evacuees from the contaminated areas based on simulation modelling

    International Nuclear Information System (INIS)

    Meckbach, R.; Chumak, V.V.

    1996-01-01

    Model calculations are being performed for the reconstruction of individual external gamma doses of population evacuated during the Chernobyl accident from the city of Pripyat and other settlements of the 30-km zone. The models are based on sets of dose rate measurements performed during the accident, on individual behavior histories of more than 30000 evacuees obtained by questionnaire survey and on location factors determined for characteristic housing buildings. Location factors were calculated by Monte Carlo simulations of photon transport for a typical housing block and village houses. Stochastic models for individual external dose reconstruction are described. Using Monte Carlo methods, frequency distributions representing the uncertainty of doses are calculated from an assessment of the uncertainty of the data. The determination of dose rate distributions in Pripyat is discussed. Exemplary results for individual external doses are presented

  15. Of earprints, fingerprints, scent dogs, cot deaths and cognitive contamination--a brief look at the present state of play in the forensic arena.

    Science.gov (United States)

    Broeders, A P A

    2006-06-02

    Over the last decades, the importance of technical and scientific evidence for the criminal justice system has been steadily increasing. Unfortunately, the weight of forensic evidence is not always easy for the trier of fact to assess, as appears from a brief discussion of some recent cases in which the weight of expert evidence was either grossly over- or understated. Also, in recent years, questions surrounding the value of forensic evidence have played a major role in the appeal and revision stages of a number of highly publicized criminal cases in several countries, including the UK and the Netherlands. Some of the present confusion is caused by the different ways in which conclusions are formulated by experts working within the traditional approach to forensic identification, as exemplified by (1) dactyloscopy and (2) the other traditional forensic identification disciplines like handwriting analysis, firearms analysis and fibre analysis, as opposed to those working within the modern scientific approach used in forensic DNA analysis. Though most clearly expressed in the way conclusions are formulated within the diverse fields, these differences essentially reflect the scientific paradigms underlying the various identification disciplines. The types of conclusions typically formulated by practitioners of the traditional identification disciplines are seen to be directly related to the two major principles underpinning traditional identification science, i.e. the uniqueness assumption and the individualization principle. The latter of these is shown to be particularly problematic, especially when carried to its extreme, as embodied in the positivity doctrine, which is almost universally embraced by the dactyloscopy profession and allows categorical identification only. Apart from issues arising out of the interpretation of otherwise valid expert evidence there is growing concern over the validity and reliability of the expert evidence submitted to courts. While

  16. Assessment of molecular contamination in mask pod

    Science.gov (United States)

    Foray, Jean Marie; Dejaune, Patrice; Sergent, Pierre; Gough, Stuart; Cheung, D.; Davenet, Magali; Favre, Arnaud; Rude, C.; Trautmann, T.; Tissier, Michel; Fontaine, H.; Veillerot, M.; Avary, K.; Hollein, I.; Lerit, R.

    2008-04-01

    Context/ study Motivation: Contamination and especially Airbone Molecular Contamination (AMC) is a critical issue for mask material flow with a severe and fairly unpredictable risk of induced contamination and damages especially for 193 nm lithography. It is therefore essential to measure, to understand and then try to reduce AMC in mask environment. Mask material flow was studied in a global approach by a pool of European partners, especially within the frame of European MEDEA+ project, so called "MUSCLE". This paper deals with results and assessment of mask pod environment in term of molecular contamination in a first step, then in a second step preliminary studies to reduce mask pod influence and contamination due to material out gassing. Approach and techniques: A specific assessment of environmental / molecular contamination along the supply chain was performed by all partners. After previous work presented at EMLC 07, further studies were performed on real time contamination measurement pod at different sites locations (including Mask manufacturing site, blank manufacturing sites, IC fab). Studies were linked to the main critical issues: cleaning, storage, handling, materials and processes. Contamination measurement campaigns were carried out along the mask supply chain using specific Adixen analyzer in order to monitor in real time organic contaminants (ppb level) in mask pods. Key results would be presented: VOC, AMC and humidity level on different kinds of mask carriers, impact of basic cleaning on pod outgassing measurement (VOC, NH3), and process influence on pod contamination... In a second step, preliminary specific pod conditioning studies for better pod environment were performed based on Adixen vacuum process. Process influence had been experimentally measured in term of molecular outgassing from mask pods. Different AMC experimental characterization methods had been carried out leading to results on a wide range of organic and inorganic

  17. Heavy metals contamination and their risk assessment around the abandoned base metals and Au-Ag mines in Korea

    Science.gov (United States)

    Chon, Hyo-Taek

    2017-04-01

    Heavy metals contamination in the areas of abandoned Au-Ag and base metal mines in Korea was investigated in order to assess the level of metal pollution, and to draw general summaries about the fate of toxic heavy metals in different environments. Efforts have been made to compare the level of heavy metals, chemical forms, and plant uptake of heavy metals in each mine site. In the base-metals mine areas, significant levels of Cd, Cu, Pb and Zn were found in mine dump soils developed over mine waste materials and tailings. Leafy vegetables tend to accumulate heavy metals(in particular, Cd and Zn) higher than other crop plants, and high metal concentrations in rice crops may affect the local residents' health. In the Au-Ag mining areas, arsenic would be the most characteristic contaminant in the nearby environment. Arsenic and heavy metals were found to be mainly associated with sulfide gangue minerals, and the mobility of these metals would be enhanced by the effect of continuing weathering and oxidation. According to the sequential extraction of metals in soils, most heavy metals were identified as non-residual chemical forms, and those are very susceptible to the change of ambient conditions of a nearby environment. The concept of pollution index(PI) of soils gives important information on the extent and degree of multi-element contamination, and can be applied to the evaluation of mine soils before their agricultural use and remediation. The risk assessment process comprising exposure assessment, dose-response assessment, and risk characterization was discussed, and the results of non-cancer risk of As, Cd, and Zn, and those of cancer risk of As were suggested.

  18. Development of a new CBR-based platform for human contamination emergency situations

    International Nuclear Information System (INIS)

    Farah, J.; Henriet, J.; Broggio, D.; Laurent, R.; Fontaine, E.; Chebel-Morello, B.; Sauget, M.; Salomon, M.; Makovicka, L.; Franck, D.

    2011-01-01

    In the case of a radiological emergency situation, involving accidental human exposure, it is necessary to establish as soon as possible a dosimetry evaluation. In most cases, this evaluation is based on numerical representations and models of the victims. Unfortunately, personalised and realistic human representations are often unavailable for the exposed subjects. Hence, existing models like the 'Reference Man' representative of the average male individual are used. However, the accuracy of the treatment depends on the similarity of the phantom to the victim. The EquiVox platform (Research of Equivalent Voxel phantom) developed in this work uses the case-based reasoning principles to retrieve, from a set of existing phantoms, the most adapted one to represent the victim. This paper introduces the EquiVox platform and gives the example of in vivo lung monitoring optimisation to prove its efficiency in choosing the right model. It also presents the artificial neural network tools being developed to adapt the model to the victim. (authors)

  19. Separation and concentration of water-borne contaminants utilizing insulator-based dielectrophoresis.

    Energy Technology Data Exchange (ETDEWEB)

    Lapizco-Encinas, Blanca Hazalia; Fiechtner, Gregory J.; Cummings, Eric B.; Davalos, Rafael V.; Kanouff, Michael P.; Simmons, Blake Alexander; McGraw, Gregory J.; Salmi, Allen J.; Ceremuga, Joseph T.; Fintschenko, Yolanda

    2006-01-01

    This report focuses on and presents the capabilities of insulator-based dielectrophoresis (iDEP) microdevices for the concentration and removal of water-borne bacteria, spores and inert particles. The dielectrophoretic behavior exhibited by the different particles of interest (both biological and inert) in each of these systems was observed to be a function of both the applied electric field and the characteristics of the particle, such as size, shape, and conductivity. The results obtained illustrate the potential of glass and polymer-based iDEP devices to act as a concentrator for a front-end device with significant homeland security and industrial applications for the threat analysis of bacteria, spores, and viruses. We observed that the polymeric devices exhibit the same iDEP behavior and efficacy in the field of use as their glass counterparts, but with the added benefit of being easily mass fabricated and developed in a variety of multi-scale formats that will allow for the realization of a truly high-throughput device. These results also demonstrate that the operating characteristics of the device can be tailored through the device fabrication technique utilized and the magnitude of the electric field gradient created within the insulating structures. We have developed systems capable of handling numerous flow rates and sample volume requirements, and have produced a deployable system suitable for use in any laboratory, industrial, or clinical setting.

  20. Feasibility Study for Installing Machine in Production Line to Avoid Particle Contamination Based on CFD Simulation

    Science.gov (United States)

    Khaokom, Adisorn; Thongsri, Jatuporn

    2017-10-01

    Ventilation system inside production line for electronic component production needs to meet the factory standard. Because it can eliminate small particles which may cause of human or machine in production as well as it can distribute the circulating air temperature uniformly. CFD is used in this research in order to study the feasibility and plan for machine layout in production line before actual installation. The simulation shows the airflow in every area inside production line. From simulation with releasing the particles from human and machine is found that this ventilation system generates airflow that makes most particles float out of the machines and no particle downs to the conveyor, it results to contamination. In addition, the simulation also shows the range of 19-26 °C air temperature that meets the factory standard. The results of this research are the parts of the data to renovate the production line to get more efficiency and proper on the production.

  1. Biosensor-based diagnostics of contaminated groundwater: assessment and remediation strategy

    International Nuclear Information System (INIS)

    Bhattacharyya, Jessica; Read, David; Amos, Sean; Dooley, Stephen; Killham, Kenneth; Paton, Graeme I.

    2005-01-01

    Shallow groundwater beneath a former airfield site in southern England has been heavily contaminated with a wide range of chlorinated solvents. The feasibility of using bacterial biosensors to complement chemical analysis and enable cost-effective, and focussed sampling has been assessed as part of a site evaluation programme. Five different biosensors, three metabolic (Vibrio fischeri, Pseudomonas fluorescens 10568 and Escherichia coli HB101) and two catabolic (Pseudomonas putida TVA8 and E. coli DH5α), were employed to identify areas where the availability and toxicity of pollutants is of most immediate environmental concern. The biosensors used showed different sensitivities to each other and to the groundwater samples tested. There was generally a good agreement with chemical analyses. The potential efficacy of remediation strategies was explored by coupling sample manipulation to biosensor tests. Manipulation involved sparging and charcoal treatment procedures to simulate remediative engineering solutions. Sparging was sufficient at most locations. - Luminescent bacteria complement chemical analysis and support remediation technology

  2. Microbiological evaluation on toxicity amelioration of soil samples contaminated with petroleum-based products

    International Nuclear Information System (INIS)

    Khairuddin Abdul Rahim; Pauline Liew Woan Ying; Ahmad Nazrul Abd Wahid; Shamsiah Abdul Rahman; Mohd Suhaimi Hamzah; Abdul Khalik Wood; Muhamat Omar

    2004-01-01

    Samples of soil materials from oil sludge landfarm in Melaka and petroleum sludge ready for disposal were analysed on their potentially toxic elements and compounds and their microbial population. These were compared against uncontaminated soil samples from agricultural plots and fresh crude petroleum samples obtained from an oil refinery in Kerteh, Terengganu. Enumeration and isolation of culturable microbial populations in the above samples were conducted using standard plate counts and screening methods. Populations of microorganisms from uncontaminated soils were tested on its potential to degrade petroleum derived products on contaminated soil samples and crude petroleum samples in a laboratory experiment. Microorganisms with great potential to degrade petroleum sludge will be further screened in further bioremediation studies in the field. (Author)

  3. All-polymeric sensing platform based on packaged self-assembled bottle microresonator (Conference Presentation)

    Science.gov (United States)

    Bernini, Romeo; Grimaldi, Immacolata A.; Persichetti, Gianluca; Testa, Genni

    2017-02-01

    In recent years, microbottle resonators that support non-degenerate whispering gallery modes (WGMs), propagating by successive total internal reflections close to the resonator surface and all along its axis, have been widely investigated due to their potential applications in optical sensing, microlasers and nonlinear optics. To overcome some drawbacks of the standard silica microbottle resonators, we focused our attention on polymers such as SU-8 resist and NOA resins. A drop of polymeric material is dispensed onto a fiber stem, providing a mechanical support for the bottle resonator, and is photo-polymerized by an UV lamp. The interrogation system, usually constituted by a tapered silica fiber evanescently coupled with the microresonator, is substituted by a more stable planar waveguide realized in SU-8 by means of standard photolithography technique. Moreover, for guarantying the stability to surrounding disturbance of the coupling between the microbottle resonator and the planar waveguide, the fiber stem is glued to substrate. Two drilled holes in the substrate allow the rise of the glue at the ends of the fiber stem and the fixing of sensor on PMMA substrate. In the present work, we presented an integrated full polymeric platform with self-assembled bottle microresonators packaged in a stable structure. SU-8 and NOA based microbottles are realized and morphologically characterized. The low autofluorescence emission and long term stability make the NOA based bottles suitable to be employed in a great variety of conditions. Bulk sensing measurements are performed by using water:ethanol solutions and a bulk sensitivity of 120 nm/RIU is estimated.

  4. Emerging Contaminants and Federal Facility Contaminants of Concern

    Science.gov (United States)

    This page links to fact sheets summarizing contaminants of concern and emerging contaminants that present unique issues and challenges to the environmental community in general and to FFRRO in particular.

  5. Technologies for remediation of radioactively contaminated sites

    International Nuclear Information System (INIS)

    1999-06-01

    This report presents particulars on environmental restoration technologies (control and treatment) which can be applied to land based, radioactively contaminated sites. The media considered include soils, groundwater, surface water, sediments, air, and terrestrial and aquatic vegetation. The technologies addressed in this report can be categorized as follows: self-attenuation (natural restoration); in-situ treatment; removal of contamination; ex-situ treatment; and transportation and final disposal. The report provides also background information about and a general approach to remediation of radioactively contaminated sites as well as some guidance for the selection of a preferred remediation technology. Examples of remediation experience in Australia and Canada are given it annexes

  6. Technologies for remediation of radioactively contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    1999-06-01

    This report presents particulars on environmental restoration technologies (control and treatment) which can be applied to land based, radioactively contaminated sites. The media considered include soils, groundwater, surface water, sediments, air, and terrestrial and aquatic vegetation. The technologies addressed in this report can be categorized as follows: self-attenuation (natural restoration); in-situ treatment; removal of contamination; ex-situ treatment; and transportation and final disposal. The report provides also background information about and a general approach to remediation of radioactively contaminated sites as well as some guidance for the selection of a preferred remediation technology. Examples of remediation experience in Australia and Canada are given it annexes Refs, figs, tabs

  7. Remediation of organic and inorganic arsenic contaminated groundwater using a nanocrystalline TiO{sub 2}-based adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Jing Chuanyong, E-mail: cyjing@rcees.ac.c [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Meng Xiaoguang; Calvache, Edwin [Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Jiang Guibin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)

    2009-08-15

    A nanocrystalline TiO{sub 2}-based adsorbent was evaluated for the simultaneous removal of As(V), As(III), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in contaminated groundwater. Batch experimental results show that As adsorption followed pseudo-second order rate kinetics. The competitive adsorption was described with the charge distribution multi-site surface complexation model (CD-MUSIC). The groundwater containing an average of 329 mug L{sup -1} As(III), 246 mug L{sup -1} As(V), 151 mug L{sup -1} MMA, and 202 mug L{sup -1} DMA was continuously passed through a TiO{sub 2} filter at an empty bed contact time of 6 min for 4 months. Approximately 11 000, 14 000, and 9900 bed volumes of water had been treated before the As(III), As(V), and MMA concentration in the effluent increased to 10 mug L{sup -1}. However, very little DMA was removed. The EXAFS results demonstrate the existence of a bidentate binuclear As(V) surface complex on spent adsorbent, indicating the oxidation of adsorbed As(III). - A nanocrystalline TiO{sub 2}-based adsorbent could be used for the simultaneous removal of As(V), As(III), MMA, and DMA in contaminated groundwater.

  8. Remediation of Organic and Inorganic Arsenic Contaminated Groundwater using a Nonocrystalline TiO2 Based Adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Jing, C.; Meng, X; Calvache, E; Jiang, G

    2009-01-01

    A nanocrystalline TiO2-based adsorbent was evaluated for the simultaneous removal of As(V), As(III), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in contaminated groundwater. Batch experimental results show that As adsorption followed pseudo-second order rate kinetics. The competitive adsorption was described with the charge distribution multi-site surface complexation model (CD-MUSIC). The groundwater containing an average of 329 ?g L-1 As(III), 246 ?g L-1 As(V), 151 ?g L-1 MMA, and 202 ?g L-1 DMA was continuously passed through a TiO2 filter at an empty bed contact time of 6 min for 4 months. Approximately 11 000, 14 000, and 9900 bed volumes of water had been treated before the As(III), As(V), and MMA concentration in the effluent increased to 10 ?g L-1. However, very little DMA was removed. The EXAFS results demonstrate the existence of a bidentate binuclear As(V) surface complex on spent adsorbent, indicating the oxidation of adsorbed As(III). A nanocrystalline TiO2-based adsorbent could be used for the simultaneous removal of As(V), As(III), MMA, and DMA in contaminated groundwater.

  9. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 5, Field Investigation report

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    An environmental investigation of ground water conditions has been undertaken at Wright-Patterson Air Force Base (WPAFB), Ohio to obtain data to assist in the evaluation of a potential removal action to prevent, to the extent practicable, migration of the contaminated ground water across Base boundaries. Field investigations were limited to the central section of the southwestern boundary of Area C and the Springfield Pike boundary of Area B. Further, the study was limited to a maximum depth of 150 feet below grade. Three primary activities of the field investigation were: (1) installation of 22 monitoring wells, (2) collection and analysis of ground water from 71 locations, (3) measurement of ground water elevations at 69 locations. Volatile organic compounds including trichloroethylene, perchloroethylene, and/or vinyl chloride were detected in concentrations exceeding Maximum Contaminant Levels (MCL) at three locations within the Area C investigation area. Ground water at the Springfield Pike boundary of Area B occurs in two primary units, separated by a thicker-than-expected clay layers. One well within Area B was determined to exceed the MCL for trichloroethylene.

  10. Base-Metal Electrode-Multilayer Ceramic Capacitors: Past, Present and Future Perspectives

    Science.gov (United States)

    Kishi, Hiroshi; Mizuno, Youichi; Chazono, Hirokazu

    2003-01-01

    Multilayer ceramic capacitor (MLCC) production and sales figures are the highest among fine-ceramic products developed in the past 30 years. The total worldwide production and sales reached 550 billion pieces and 6 billion dollars, respectively in 2000. In the course of progress, the development of base-metal electrode (BME) technology played an important role in expanding the application area. In this review, the recent progress in MLCCs with BME nickel (Ni) electrodes is reviewed from the viewpoint of nonreducible dielectric materials. Using intermediate-ionic-size rare-earth ion (Dy2O3, Ho2O3, Er2O3, Y2O3) doped BaTiO3 (ABO3)-based dielectrics, highly reliable Ni-MLCCs with a very thin layer below 2 μm in thickness have been developed. The effect of site occupancy of rare-earth ions in BaTiO3 on the electrical properties and microstructure of nonreducible dielectrics is studied systematically. It appears that intermediate-ionic-size rare-earth ions occupy both A- and B-sites in the BaTiO3 lattice and effectively control the donor/acceptor dopant ratio and microstructural evolution. The relationship between the electrical properties and the microstructure of Ni-MLCCs is also presented.

  11. Lithography-based ceramic manufacture (LCM) of auxetic structures: present capabilities and challenges

    International Nuclear Information System (INIS)

    Lantada, Andrés Díaz; De Blas Romero, Adrián; Schwentenwein, Martin; Jellinek, Christopher; Homa, Johannes

    2016-01-01

    Auxetic metamaterials are known for having a negative Poisson’s ratio (NPR) and for displaying the unexpected properties of lateral expansion when stretched and densification when compressed. Even though a wide set of micro-manufacturing resources have been used for the development of auxetic metamaterials and related devices, additional precision and an extension to other families of materials is needed for their industrial expansion. In addition, their manufacture using ceramic materials is still challenging. In this study we present a very promising approach for the development of auxetic metamaterials and devices based on the use of lithography-based ceramic manufacturing. The process stands out for its precision and complex three-dimensional geometries attainable, without the need of supporting structures, and for enabling the manufacture of ceramic auxetics with their geometry controlled from the design stage with micrometric precision. To our knowledge it represents the first example of application of this technology to the manufacture of auxetic geometries using ceramic materials. We have used a special three-dimensional auxetic design whose remarkable NPR has been previously highlighted. (paper)

  12. Present status of Kyoto University reactor research result data base KURRIP

    International Nuclear Information System (INIS)

    Takeuchi, Takayuki

    1986-01-01

    The construction of KURRIP data base was begun in 1982, and in 1983, the data base concerning the literatures published in five years from 1978 to 1982 was set up in the Kyoto University Large Computer Center, and it has become available generally. In fiscal year 1984, the data concerning the literatures published from 1974 to 1977 and in 1983 were added. Moreover in this fiscal year, the work is carried out to input the data concerning the literatures published from 1970 to 1973 and in 1984. The data retrievable at present are those for ten years from 1974 to 1983. The results of having retrieved these data about a number of items are reported in this paper. The classification according to the places of employment of authors, the classification according to the kinds of literatures, the classification according to the languages used, the classification according to the installations used, the classification according to the fields of research, and the classification according to the magazines which printed the data are reported. (Kako, I.)

  13. A comprehensive review on droplet-based bioprinting: Past, present and future.

    Science.gov (United States)

    Gudapati, Hemanth; Dey, Madhuri; Ozbolat, Ibrahim

    2016-09-01

    Droplet-based bioprinting (DBB) offers greater advantages due to its simplicity and agility with precise control on deposition of biologics including cells, growth factors, genes, drugs and biomaterials, and has been a prominent technology in the bioprinting community. Due to its immense versatility, DBB technology has been adopted by various application areas, including but not limited to, tissue engineering and regenerative medicine, transplantation and clinics, pharmaceutics and high-throughput screening, and cancer research. Despite the great benefits, the technology currently faces several challenges such as a narrow range of available bioink materials, bioprinting-induced cell damage at substantial levels, limited mechanical and structural integrity of bioprinted constructs, and restrictions on the size of constructs due to lack of vascularization and porosity. This paper presents a first-time review of DBB and comprehensively covers the existing DBB modalities including inkjet, electrohydrodynamic, acoustic, and micro-valve bioprinting. The recent notable studies are highlighted, the relevant bioink biomaterials and bioprinters are expounded, the application areas are presented, and the future prospects are provided to the reader. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Resonant tunneling diodes based on ZnO for quantum cascade structures (Conference Presentation)

    Science.gov (United States)

    Hinkov, Borislav; Schwarz, Benedikt; Harrer, Andreas; Ristanic, Daniela; Schrenk, Werner; Hugues, Maxime; Chauveau, Jean-Michel; Strasser, Gottfried

    2017-02-01

    The terahertz (THz) spectral range (lambda 30µm - 300µm) is also known as the "THz-gap" because of the lack of compact semiconductor devices. Various real-world applications would strongly benefit from such sources like trace-gas spectroscopy or security-screening. A crucial step is the operation of THz-emitting lasers at room temperature. But this seems out of reach with current devices, of which GaAs-based quantum cascade lasers (QCLs) seem to be the most promising ones. They are limited by the parasitic, non-optical LO-phonon transitions (36meV in GaAs), being on the same order as the thermal energy at room temperature (kT = 26meV). This can be solved by using larger LO-phonon materials like ZnO (E_LO = 72meV). But to master the fabrication of ZnO-based QC structures, a high quality epitaxial growth is crucial followed by a well-controlled fabrication process including ZnO/ZnMgO etching. We use devices grown on m-plane ZnO-substrate by molecular beam epitaxy. They are patterned by reactive ion etching in a CH4-based chemistry (CH4:H2:Ar/30:3:3 sccm) into 50μm to 150μm square mesas. Resonant tunneling diode structures are investigated in this geometry and are presented including different barrier- and well-configurations. We extract contact resistances of 8e-5 Omega cm^2 for un-annealed Ti/Au contacts and an electron mobility of above 130cm^2/Vs, both in good agreement with literature. Proving that resonant electron tunneling can be achieved in ZnO is one of the crucial building blocks of a QCL. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 665107.

  15. Method for visualization and presentation of priceless old prints based on precise 3D scan

    Science.gov (United States)

    Bunsch, Eryk; Sitnik, Robert

    2014-02-01

    Graphic prints and manuscripts constitute main part of the cultural heritage objects created by the most of the known civilizations. Their presentation was always a problem due to their high sensitivity to light and changes of external conditions (temperature, humidity). Today it is possible to use an advanced digitalization techniques for documentation and visualization of mentioned objects. In the situation when presentation of the original heritage object is impossible, there is a need to develop a method allowing documentation and then presentation to the audience of all the aesthetical features of the object. During the course of the project scans of several pages of one of the most valuable books in collection of Museum of Warsaw Archdiocese were performed. The book known as "Great Dürer Trilogy" consists of three series of woodcuts by the Albrecht Dürer. The measurement system used consists of a custom designed, structured light-based, high-resolution measurement head with automated digitization system mounted on the industrial robot. This device was custom built to meet conservators' requirements, especially the lack of ultraviolet or infrared radiation emission in the direction of measured object. Documentation of one page from the book requires about 380 directional measurements which constitute about 3 billion sample points. The distance between the points in the cloud is 20 μm. Provided that the measurement with MSD (measurement sampling density) of 2500 points makes it possible to show to the publicity the spatial structure of this graphics print. An important aspect is the complexity of the software environment created for data processing, in which massive data sets can be automatically processed and visualized. Very important advantage of the software which is using directly clouds of points is the possibility to manipulate freely virtual light source.

  16. A chaotic-dynamical conceptual model to describe fluid flow and contaminant transport in a fractured vadose zone. 1997 progress report and presentations at the annual meeting, Ernest Orlando Lawrence Berkeley National Laboratory, December 3-4, 1997

    International Nuclear Information System (INIS)

    Faybishenko, B.; Doughty, C.; Geller, J.

    1998-07-01

    Understanding subsurface flow and transport processes is critical for effective assessment, decision-making, and remediation activities for contaminated sites. However, for fluid flow and contaminant transport through fractured vadose zones, traditional hydrogeological approaches are often found to be inadequate. In this project, the authors examine flow and transport through a fractured vadose zone as a deterministic chaotic dynamical process, and develop a model of it in these terms. Initially, the authors examine separately the geometric model of fractured rock and the flow dynamics model needed to describe chaotic behavior. Ultimately they will put the geometry and flow dynamics together to develop a chaotic-dynamical model of flow and transport in a fractured vadose zone. They investigate water flow and contaminant transport on several scales, ranging from small-scale laboratory experiments in fracture replicas and fractured cores, to field experiments conducted in a single exposed fracture at a basalt outcrop, and finally to a ponded infiltration test using a pond of 7 by 8 m. In the field experiments, they measure the time-variation of water flux, moisture content, and hydraulic head at various locations, as well as the total inflow rate to the subsurface. Such variations reflect the changes in the geometry and physics of water flow that display chaotic behavior, which they try to reconstruct using the data obtained. In the analysis of experimental data, a chaotic model can be used to predict the long-term bounds on fluid flow and transport behavior, known as the attractor of the system, and to examine the limits of short-term predictability within these bounds. This approach is especially well suited to the need for short-term predictions to support remediation decisions and long-term bounding studies. View-graphs from ten presentations made at the annual meeting held December 3--4, 1997 are included in an appendix to this report

  17. JPL Contamination Control Engineering

    Science.gov (United States)

    Blakkolb, Brian

    2013-01-01

    JPL has extensive expertise fielding contamination sensitive missions-in house and with our NASA/industry/academic partners.t Development and implementation of performance-driven cleanliness requirements for a wide range missions and payloads - UV-Vis-IR: GALEX, Dawn, Juno, WFPC-II, AIRS, TES, et al - Propulsion, thermal control, robotic sample acquisition systems. Contamination control engineering across the mission life cycle: - System and payload requirements derivation, analysis, and contamination control implementation plans - Hardware Design, Risk trades, Requirements V-V - Assembly, Integration & Test planning and implementation - Launch site operations and launch vehicle/payload integration - Flight ops center dot Personnel on staff have expertise with space materials development and flight experiments. JPL has capabilities and expertise to successfully address contamination issues presented by space and habitable environments. JPL has extensive experience fielding and managing contamination sensitive missions. Excellent working relationship with the aerospace contamination control engineering community/.

  18. A High Resolution Technology-based Emissions Inventory for Nepal: Present and Future Scenario

    Science.gov (United States)

    Sadavarte, P.; Das, B.; Rupakheti, M.; Byanju, R.; Bhave, P.

    2016-12-01

    A comprehensive regional assessment of emission sources is a major hindrance for a complete understanding of the air quality and for designing appropriate mitigation solutions in Nepal, a landlocked country in foothills of the Himalaya. This study attempts, for the first time, to develop a fine resolution (1km × 1km) present day emission inventory of Nepal with a higher tier approach using our understanding of the currently used technologies, energy consumption used in various energy sectors and its resultant emissions. We estimate present-day emissions of aerosols (BC, OC and PM2.5), trace gases (SO2, CO, NOX and VOC) and greenhouse gases (CO2, N2O and CH4) from non-open burning sources (residential, industry, transport, commercial) and open-burning sources (agriculture and municipal solid waste burning) for the base year 2013. We used methodologies published in literatures, and both primary and secondary data to estimate energy production and consumption in each sector and its sub-sector and associated emissions. Local practices and activity rates are explicitly accounted for energy consumption and dispersed often under-documented emission sources like brick manufacturing, diesel generator sets, mining, stone crushing, solid waste burning and diesel use in farms are considered. Apart from pyrogenic source of CH4 emissions, methanogenic and enteric fermentation sources are also accounted. Region-specific and newly measured country-specific emission factors are used for emission estimates. Activity based proxies are used for spatial and temporal distribution of emissions. Preliminary results suggest that 80% of national energy consumption is in residential sector followed by industry (8%) and transport (7%). More than 90% of the residential energy is supplied by biofuel which needs immediate attention to reduce emissions. Further, the emissions would be compared with other contemporary studies, regional and global datasets and used in the model simulations to

  19. Management of risk of microbial cross-contamination from uncooked frozen hamburgers by alcohol-based hand sanitizer.

    Science.gov (United States)

    Schaffner, Donald W; Schaffner, Kristin M

    2007-01-01

    This research was undertaken to determine the effectiveness of an alcohol-based hand sanitizer on hands contaminated with a nonpathogen surrogate for Escherichia coli O157:H7, where the source of the contamination was frozen hamburger patties. A nonpathogenic nalidixic acid-resistant food-grade strain of Enterobacter aerogenes was used to inoculate frozen hamburger patties composed of 76% lean beef and 24% fat. Thirty-two individuals participated to produce the data used in this study. Each participant handled nine patties at least three times, a sample for microbiological analysis was collected from the surface of one hand, the participant sanitized both hands, and a sample was collected from the other hand. Burger handling created perceptible and visible food debris on the hands of most participants. Computer simulations also were used to perform a variety of risk calculations. The average reduction in bacteria from the use of sanitizer on hands contaminated by frozen burgers containing E. aerogenes was 2.6 +/- 0.7 log CFU per hand. An experiment designed to simultaneously test the effect of sanitizer on E. aerogenes and E. coli O157:H7 also revealed no significant difference in sanitizer effectiveness against the two organisms. The results of the real-world risk estimation calculations (using the actual prevalence and concentration of E. coli O157:H7 in ground beef) predict that once in 1 million trials, a single pathogen cell will be transferred to a single lettuce piece. The effectiveness of this sanitizer intervention was similar to that for hand washing and glove use previously reported. The person-to-person microbial reduction variability from sanitizer use is similar to published data for glove use and was less variable than published data on hand washing effectiveness.

  20. Grouting design based on characterization of the fractured rock. Presentation and demonstration of a methodology

    Energy Technology Data Exchange (ETDEWEB)

    Fransson, Aasa (SWECO Environment, Stockholm (Sweden); Chalmers Univ. of Technology, Goeteborg (Sweden))

    2008-12-15

    The design methodology presented in this document is based on an approach that considers the individual fractures. The observations and analyses made during production enable the design to adapt to the encountered conditions. The document is based on previously published material and overview flow charts are used to show the different steps. Parts of or the full methodology has been applied for a number of tunneling experiments and projects. SKB projects in the Aespoe tunnel include a pillar experiment and pre-grouting of a 70 meter long tunnel (TASQ). Further, for Hallandsas railway tunnel (Skaane south Sweden), a field pre-grouting experiment and design and post-grouting of a section of 133 meters have been made. For the Nygard railway tunnel (north of Goeteborg, Sweden), design and grouting of a section of 86 meters (pre-grouting) and 60 meters (post-grouting) have been performed. Finally, grouting work at the Tornskog tunnel (Stockholm, Sweden) included design and grouting along a 100 meter long section of one of the two tunnel tubes. Of importance to consider when doing a design and evaluating the result are: - The identification of the extent of the grouting needed based on inflow requirements and estimates of tunnel inflow before grouting. - The selection of grout and performance of grouting materials including penetration ability and length. The penetration length is important for the fan geometry design. - The ungrouted compared to the grouted and excavated rock mass conditions: estimates of tunnel inflow and (if available) measured inflows after grouting and excavation. Identify if possible explanations for deviations. For the Hallandsas, Nygard and Tornskog tunnel sections, the use of a Pareto distribution and the estimate of tunnel inflow identified a need for sealing small aperture fractures (< 50 - 100 mum) to meet the inflow requirements. The tunneling projects show that using the hydraulic aperture as a basis for selection of grout is a good

  1. Grouting design based on characterization of the fractured rock. Presentation and demonstration of a methodology

    International Nuclear Information System (INIS)

    Fransson, Aasa

    2008-12-01

    The design methodology presented in this document is based on an approach that considers the individual fractures. The observations and analyses made during production enable the design to adapt to the encountered conditions. The document is based on previously published material and overview flow charts are used to show the different steps. Parts of or the full methodology has been applied for a number of tunneling experiments and projects. SKB projects in the Aespoe tunnel include a pillar experiment and pre-grouting of a 70 meter long tunnel (TASQ). Further, for Hallandsas railway tunnel (Skaane south Sweden), a field pre-grouting experiment and design and post-grouting of a section of 133 meters have been made. For the Nygard railway tunnel (north of Goeteborg, Sweden), design and grouting of a section of 86 meters (pre-grouting) and 60 meters (post-grouting) have been performed. Finally, grouting work at the Tornskog tunnel (Stockholm, Sweden) included design and grouting along a 100 meter long section of one of the two tunnel tubes. Of importance to consider when doing a design and evaluating the result are: - The identification of the extent of the grouting needed based on inflow requirements and estimates of tunnel inflow before grouting. - The selection of grout and performance of grouting materials including penetration ability and length. The penetration length is important for the fan geometry design. - The ungrouted compared to the grouted and excavated rock mass conditions: estimates of tunnel inflow and (if available) measured inflows after grouting and excavation. Identify if possible explanations for deviations. For the Hallandsas, Nygard and Tornskog tunnel sections, the use of a Pareto distribution and the estimate of tunnel inflow identified a need for sealing small aperture fractures (< 50 - 100 μm) to meet the inflow requirements. The tunneling projects show that using the hydraulic aperture as a basis for selection of grout is a good

  2. Contamination Control Techniques

    Energy Technology Data Exchange (ETDEWEB)

    EBY, J.L.

    2000-05-16

    Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.

  3. Contamination Control Techniques

    International Nuclear Information System (INIS)

    EBY, J.L.

    2000-01-01

    Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics

  4. Unregulated Contaminant Monitoring Program Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — EPA uses the Unregulated Contaminant Monitoring (UCM) program to collect data for contaminants suspected to be present in drinking water, but that do not have...

  5. Earthworms and in vitro physiologically-based extraction tests: complementary tools for a holistic approach towards understanding risk at arsenic-contaminated sites.

    Science.gov (United States)

    Button, Mark; Watts, Michael J; Cave, Mark R; Harrington, Chris F; Jenkin, Gawen T

    2009-04-01

    The relationship of the total arsenic content of a soil and its bioaccumulation by earthworms (Lumbricus rubellus and Dendrodrilus rubidus) to the arsenic fraction bioaccessible to humans, measured using an in vitro physiologically-based extraction test (PBET), was investigated. Soil and earthworm samples were collected at 24 sites at the former arsenic mine at the Devon Great Consols (DGC) in southwest England (UK), along with an uncontaminated site in Nottingham, UK, for comparison. Analysis of soil and earthworm total arsenic via inductively coupled plasma mass spectrometry (ICP-MS) was performed following a mixed acid digestion. Arsenic concentrations in the soil were elevated (204-9,025 mg kg(-1)) at DGC. The arsenic bioaccumulation factor (BAF) for both earthworm species was found to correlate positively with the human bioaccessible fraction (HBF), although the correlation was only significant (P earthworms as complementary tools is explored as a holistic and multidisciplinary approach towards understanding risk at contaminated sites. Arsenic resistant earthworm species such as the L. rubellus populations at DGC are presented as a valuable tool for understanding risk at highly contaminated sites.

  6. Decision making support of the management of technogenically contaminated territories basing on risk analysis with use of geographic information technology

    International Nuclear Information System (INIS)

    Yatsalo, B.I.; Demin, V.F.

    2002-01-01

    Overall questions of decision making support of the contaminated territories management on a basis of risk assessment were considered. Characteristics and possibilities of the applied geoinformation system of decision making support PRANA developed for the risk control and rehabilitation of contaminated territories are demonstrated. The PRANA system involves estimations of all fundamental characteristics of risk during analysis of results and contaminated territories management [ru

  7. Development of an Integrated Multi-Contaminant Removal Process Applied to Warm Syngas Cleanup for Coal-Based Advanced Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Howard

    2010-11-30

    This project met the objective to further the development of an integrated multi-contaminant removal process in which H2S, NH3, HCl and heavy metals including Hg, As, Se and Cd present in the coal-derived syngas can be removed to specified levels in a single/integrated process step. The process supports the mission and goals of the Department of Energy's Gasification Technologies Program, namely to enhance the performance of gasification systems, thus enabling U.S. industry to improve the competitiveness of gasification-based processes. The gasification program will reduce equipment costs, improve process environmental performance, and increase process reliability and flexibility. Two sulfur conversion concepts were tested in the laboratory under this project, i.e., the solventbased, high-pressure University of California Sulfur Recovery Process High Pressure (UCSRP-HP) and the catalytic-based, direct oxidation (DO) section of the CrystaSulf-DO process. Each process required a polishing unit to meet the ultra-clean sulfur content goals of <50 ppbv (parts per billion by volume) as may be necessary for fuel cells or chemical production applications. UCSRP-HP was also tested for the removal of trace, non-sulfur contaminants, including ammonia, hydrogen chloride, and heavy metals. A bench-scale unit was commissioned and limited testing was performed with simulated syngas. Aspen-Plus®-based computer simulation models were prepared and the economics of the UCSRP-HP and CrystaSulf-DO processes were evaluated for a nominal 500 MWe, coal-based, IGCC power plant with carbon capture. This report covers the progress on the UCSRP-HP technology development and the CrystaSulf-DO technology.

  8. The analysis of photon pair source at telecom wavelength based on the BBO crystal (Conference Presentation)

    Science.gov (United States)

    Gajewski, Andrzej; Kolenderski, Piotr L.

    2016-10-01

    There are several problems that must be solved in order to increase the distance of quantum communication protocols based on photons as an information carriers. One of them is the dispersion, whose effects can be minimized by engineering spectral properties of transmitted photons. In particular, it is expected that positively correlated photon pairs can be very useful. We present the full characterization of a source of single photon pairs at a telecom wavelength based on type II spontaneous parametric down conversion (SPDC) process in a beta-barium borate (BBO) crystal. In the type II process, a pump photon, which is polarized extraordinarily, splits in a nonlinear medium into signal and idler photons, which are polarized perpendicularly to each other. In order for the process to be efficient a phase matching condition must be fulfilled. These conditions originate from momentum and energy conservation rules and put severe restrictions on source parameters. Seemingly, these conditions force the photon pair to be negatively correlated in their spectral domain. However, it is possible to achieve positive correlation for pulsed pumping. The experimentally available degrees of freedom of a source are the width of the pumping beam, the collected modes' widths, the length of the nonlinear crystal and the duration of the pumping pulse. In our numerical model we use the following figures of merit: the pair production rate, the efficiency of photon coupling into a single mode fiber, the spectral correlation of the coupled photon pair. The last one is defined as the Pearson correlation parameter for a joint spectral distribution. The aim here is to find the largest positive spectral correlation and the highest coupling efficiency. By resorting to the numerical model Ref. [1] we showed in Ref. [2], that by careful adjustment of the pump's and the collected modes' characteristics, one can optimize any of the source's parameters. Our numerical outcomes conform to the

  9. Presenting the students’ academic achievement causal model based on goal orientation

    Directory of Open Access Journals (Sweden)

    EBRAHIM NASIRI

    2017-10-01

    Full Text Available Introduction: Several factors play a role in academic achievement, individual’s excellence and capability to do actions and tasks that the learner is in charge of in learning areas. The main goal of this study was to present academic achievement causal model based on the dimensions of goal orientation and learning approaches among the students of Medical Science and Dentistry courses in Guilan University of Medical Sciences in 2013. Methods: This study is based on a cross-sectional model. The participants included 175 first and second year students of the Medical and Dentistry schools in Guilan University of Medical Sciences selected by random cluster sampling [121 persons (69% Medical Basic Science students and 54 (30.9% Dentistry students]. The measurement tool included the Goal Orientation Scale of Bouffard and Study Process Questionnaire of Biggs and the students’ Grade Point Average. The study data were analyzed using Pearson correlation coefficient and structural equations modeling. SPSS 14 and Amos were used to analyze the data. Results: The results indicated a significant relationship between goal orientation and learning strategies (P<0.05. In addition, the results revealed that a significant relationship exists between learning strategies [Deep Learning (r=0.37, P<0.05, Surface Learning (r=-0.21, P<0.05], and academic achievement. The suggested model of research is fitted to the data of the research. Conclusion: Results showed that the students’ academic achievement model fits with experimental data, so it can be used in learning principles which lead to students’ achievement in learning.

  10. Piezoelectric nanogenerators based on ZnO and M13 Bacteriophage nanostructures (Conference Presentation)

    Science.gov (United States)

    Shin, Dong-Myeong; Kim, Kyujungg; Hong, Suck Won; Oh, Jin-Woo; Kim, Hyung Kook; Hwang, Yoon-Hwae

    2016-09-01

    Recently, the portable and wearable electronic devices, operated in the power range of microwatt to miliwatt, become available thank to the nanotechnology development and become an essential element for a comfortable life. Our recent research interest mainly focuses on the fabrication of piezoelectric nanogenerators based on smart nanomaterials such as zinc oxide novel nanostructure, M13 bacteriophage. In this talk, we present a simple strategy for fabricating the freestanding ZnO nanorods/graphene/ZnO nanorods double sided heterostructures. The characterization of the double sided heterostructures by using SEM, and Raman scattering spectroscopy reveals the key process and working mechanism of a formation of the heterostructure. The mechanism is discussed in detail in term of the decomposed seed layer and the vacancy defect of graphene. The approach consists of a facile one-step fabrication process and could achieve ZnO coverage with a higher number density than that of the epitaxial single heterostructure. The resulting improvement in the number density of nanorods has a direct beneficial effect on the double side heterostructured nanogenerator performance. The total output voltage and current density are improved up to 2 times compared to those of a single heterostructure due to the coupling of the piezoelectric effects from both upward and downward grown nanorods. The facile one-step fabrication process suggests that double sided heterostructures would improve the performance of electrical and optoelectrical device, such as touch pad, pressure sensor, biosensor and dye-sensitized solar cells. Further, ioinspired nanogenerators based on vertically aligned phage nanopillars are inceptively demonstrated. Vertically aligned phage nanopillars enable not only a high piezoelectric response but also a tuneable piezoelectricity. Piezoelectricity is also modulated by tuning of the protein's dipoles in each phage. The sufficient electrical power from phage nanopillars thus

  11. Response of soil microbial communities to red mud-based stabilizer remediation of cadmium-contaminated farmland.

    Science.gov (United States)

    Li, Hui; Liu, Lemian; Luo, Lin; Liu, Yan; Wei, Jianhong; Zhang, Jiachao; Yang, Yuan; Chen, Anwei; Mao, Qiming; Zhou, Yaoyu

    2018-04-01

    In this work, a field test was conducted to investigate the effects of heavy metal stabilizer addition on brown rice and microbial variables in a cadmium (Cd)-contaminated farmland from April to October in 2016. Compared with the control, red mud-based stabilizer (RMDL) effectively reduced the concentration of Cd in brown rice (with the removal rate of 48.14% in early rice, 20.24 and 47.62% in late rice). The results showed that adding 0.3 kg m -2 RDML in early rice soil or soil for both early and late rice increased the microbial biomass carbon (MBC), the number of culturable heterotrophic bacteria and fungi, and the catalase activity in soil at different stages of paddy rice growth. Furthermore, there was no notable difference in the diversity of the bacterial species, community composition, and relative abundance at phylum (or class) or operational taxonomic unit (OTU) levels between the control and treatment (RMDL addition) groups. In a word, RMDL could be highly recommended as an effective remediation stabilizer for Cd-contaminated farmland, since its continuous application in paddy soil cultivating two seasons rice soil could effectively decrease the Cd content in brown rice and had no negative impact on soil microorganisms.

  12. Pig Manure Contamination Marker Selection Based on the Influence of Biological Treatment on the Dominant Fecal Microbial Groups▿

    Science.gov (United States)

    Marti, Romain; Dabert, Patrick; Pourcher, Anne-Marie

    2009-01-01

    The objective of this study was to identify a microbial marker for pig manure contamination. We quantified the persistence of four dominant bacterial groups from the pig intestinal tract throughout manure handling at 10 livestock operations (including aerobic digestion) by using molecular typing. The partial 16S rRNA genes of Bacteroides-Prevotella, Eubacterium-Clostridiaceae, Bacillus-Streptococcus-Lactobacillus (BSL), and Bifidobacterium group isolates were amplified and analyzed by capillary electrophoresis single-strand conformation polymorphism. The most dominant bacterial populations were identified by cloning and sequencing their 16S rRNA genes. The results showed that Bifidobacterium spp. and, to a lesser extent, members of the BSL group, were less affected by the aerobic treatment than either Eubacterium-Clostridiaceae or Bacteroides-Prevotella. Two Bifidobacterium species found in raw manure were still present in manure during land application, suggesting that they can survive outside the pig intestinal tract and also survive aerobic treatment. The 16S-23S rRNA internal transcribed spacer of one species, Bifidobacterium thermacidophilum subsp. porcinum, was sequenced, and a specific pair of primers was designed for its detection in the environment. With this nested PCR assay, this potential marker was not detected in samples from 30 bovine, 30 poultry, and 28 human fecal samples or in 15 urban wastewater effluents. As it was detected in runoff waters after spreading of pig manure, we propose this marker as a suitable microbial indicator of pig manure contamination. PMID:19525269

  13. Pig manure contamination marker selection based on the influence of biological treatment on the dominant fecal microbial groups.

    Science.gov (United States)

    Marti, Romain; Dabert, Patrick; Pourcher, Anne-Marie

    2009-08-01

    The objective of this study was to identify a microbial marker for pig manure contamination. We quantified the persistence of four dominant bacterial groups from the pig intestinal tract throughout manure handling at 10 livestock operations (including aerobic digestion) by using molecular typing. The partial 16S rRNA genes of Bacteroides-Prevotella, Eubacterium-Clostridiaceae, Bacillus-Streptococcus-Lactobacillus (BSL), and Bifidobacterium group isolates were amplified and analyzed by capillary electrophoresis single-strand conformation polymorphism. The most dominant bacterial populations were identified by cloning and sequencing their 16S rRNA genes. The results showed that Bifidobacterium spp. and, to a lesser extent, members of the BSL group, were less affected by the aerobic treatment than either Eubacterium-Clostridiaceae or Bacteroides-Prevotella. Two Bifidobacterium species found in raw manure were still present in manure during land application, suggesting that they can survive outside the pig intestinal tract and also survive aerobic treatment. The 16S-23S rRNA internal transcribed spacer of one species, Bifidobacterium thermacidophilum subsp. porcinum, was sequenced, and a specific pair of primers was designed for its detection in the environment. With this nested PCR assay, this potential marker was not detected in samples from 30 bovine, 30 poultry, and 28 human fecal samples or in 15 urban wastewater effluents. As it was detected in runoff waters after spreading of pig manure, we propose this marker as a suitable microbial indicator of pig manure contamination.

  14. Real-time temperature feedback for nanoparticles based tumor thermal treatment (Conference Presentation)

    Science.gov (United States)

    Steinberg, Idan; Tamir, Gil; Gannot, Israel

    2017-02-01

    Systemic hyperthermia therapy exploits the fact that cancer cells are more sensitive to elevated temperatures than healthy tissue. Systemic application of hyperthermia externally usually leads to low efficiency treatment. Recently, our group and others have proposed an antibody conjugated magnetic nanoparticles (MNPs) approach to overcome the limitation of systemic hyperthermia. MNPs can bind specifically to the tumor sites, thus delivering internal highly effective targeted hyperthermia. However, such internal mechanism requires more complicated controls and monitoring. This current work presents a deep tissue temperature monitoring method to control hyperthermia effectiveness and minimize collateral damage to surrounding tissues. A low-frequency narrowband modulation of the RF field used for MNP heating leads to the generation of diffused thermal waves which propagate to the tissue surface and captured by a thermal camera. A Fourier domain, analytical heat transfer model is used for temperature monitoring algorithm. The ill-posed thermal inverse problem is solved efficiently by iterating over the source power until both the amplitude and phase match the recorded thermal image sequence. The narrow bandwidth thermal stimulation enables acquiring deep signals with high SNR. We show that thermal transverse resolution improves as the stimulation frequency increases even slightly above DC, enabling better heat source transverse separation and margin identification in the case of distributed tumors. These results can be used as a part of an overall image and treat system for efficient detection of tumors, manipulation of MNPs and monitoring MNP based hyperthermia.

  15. Automation of Presentation Record Production Based on Rich-Media Technology Using SNT Petri Nets Theory

    Directory of Open Access Journals (Sweden)

    Ivo Martiník

    2015-01-01

    Full Text Available Rich-media describes a broad range of digital interactive media that is increasingly used in the Internet and also in the support of education. Last year, a special pilot audiovisual lecture room was built as a part of the MERLINGO (MEdia-rich Repository of LearnING Objects project solution. It contains all the elements of the modern lecture room determined for the implementation of presentation recordings based on the rich-media technologies and their publication online or on-demand featuring the access of all its elements in the automated mode including automatic editing. Property-preserving Petri net process algebras (PPPA were designed for the specification and verification of the Petri net processes. PPPA does not need to verify the composition of the Petri net processes because all their algebraic operators preserve the specified set of the properties. These original PPPA are significantly generalized for the newly introduced class of the SNT Petri process and agent nets in this paper. The PLACE-SUBST and ASYNC-PROC algebraic operators are defined for this class of Petri nets and their chosen properties are proved. The SNT Petri process and agent nets theory were significantly applied at the design, verification, and implementation of the programming system ensuring the pilot audiovisual lecture room functionality.

  16. Disseminating research information through Facebook and Twitter (DRIFT): presenting an evidence-based framework.

    Science.gov (United States)

    Ryan, Gemma; Sfar-Gandoura, Hanah

    2018-05-02

    The social media platform Facebook boasts of having more than 1,284 million daily active users globally. A large proportion of adults use the internet to seek health-related information. To critically analyse the use of social media to engage parents of children with attention deficit hyperactivity disorder (ADHD) with the findings of clinical research. Observation and qualitative content analysis combined with Facebook Audience Insights were used to evaluate the levels of engagement and interaction with different types of research information. More than 1,100 people from 41 nations engaged with the group. Sharing information through a range of Facebook functions was found to successfully achieve engagement and reach this demographic nationally and internationally. Lay research users are eager to engage and understand clinical research. Social media platforms are an appropriate way to disseminate research. This paper presents a much-needed evidence-based framework that nursing and health researchers can use for effective communication. © 2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

  17. Needle-based polarization-sensitive OCT of breast tumor (Conference Presentation)

    Science.gov (United States)

    Villiger, Martin; Lorenser, Dirk; McLaughlin, Robert A.; Quirk, Bryden C.; Kirk, Rodney W.; Bouma, Brett E.; Sampson, David D.

    2016-03-01

    OCT imaging through miniature needle probes has extended the range of OCT and enabled structural imaging deep inside breast tissue, with the potential to assist in the intraoperative assessment of tumor margins. However, in many situations, scattering contrast alone is insufficient to clearly identify and delineate malignant areas. Here, we present a portable, depth-encoded polarization-sensitive OCT system, connected to a miniature needle probe. From the measured polarization states we constructed the tissue Mueller matrix at each sample location and improved the accuracy of the measured polarization states through incoherent averaging before retrieving the depth-resolved tissue birefringence. With the Mueller matrix at hand, additional polarization properties such as depolarization are readily available. We then imaged freshly excised breast tissue from a patient undergoing lumpectomy. The reconstructed local retardation highlighted regions of connective tissue, which exhibited birefringence due to the abundance of collagen fibers, and offered excellent contrast to areas of malignant tissue, which exhibited less birefringence due to their different tissue composition. Results were validated against co-located histology sections. The combination of needle-based imaging with the complementary contrast provided by polarization-sensitive analysis offers a powerful instrument for advanced tissue imaging and has potential to aid in the assessment of tumor margins during the resection of breast cancer.

  18. Novel peptide-based platform for the dual presentation of biologically active peptide motifs on biomaterials.

    Science.gov (United States)

    Mas-Moruno, Carlos; Fraioli, Roberta; Albericio, Fernando; Manero, José María; Gil, F Javier

    2014-05-14

    Biofunctionalization of metallic materials with cell adhesive molecules derived from the extracellular matrix is a feasible approach to improve cell-material interactions and enhance the biointegration of implant materials (e.g., osseointegration of bone implants). However, classical biomimetic strategies may prove insufficient to elicit complex and multiple biological signals required in the processes of tissue regeneration. Thus, newer strategies are focusing on installing multifunctionality on biomaterials. In this work, we introduce a novel peptide-based divalent platform with the capacity to simultaneously present distinct bioactive peptide motifs in a chemically controlled fashion. As a proof of concept, the integrin-binding sequences RGD and PHSRN were selected and introduced in the platform. The biofunctionalization of titanium with this platform showed a positive trend towards increased numbers of cell attachment, and statistically higher values of spreading and proliferation of osteoblast-like cells compared to control noncoated samples. Moreover, it displayed statistically comparable or improved cell responses compared to samples coated with the single peptides or with an equimolar mixture of the two motifs. Osteoblast-like cells produced higher levels of alkaline phosphatase on surfaces functionalized with the platform than on control titanium; however, these values were not statistically significant. This study demonstrates that these peptidic structures are versatile tools to convey multiple biofunctionality to biomaterials in a chemically defined manner.

  19. Coexisting sea-based and land-based sources of contamination by PAHs in the continental shelf sediments of Coatzacoalcos River discharge area (Gulf of Mexico).

    Science.gov (United States)

    Ruiz-Fernández, Ana Carolina; Portela, Julián Mauricio Betancourt; Sericano, José Luis; Sanchez-Cabeza, Joan-Albert; Espinosa, Luisa Fernanda; Cardoso-Mohedano, José Gilberto; Pérez-Bernal, Libia Hascibe; Tinoco, Jesús Antonio Garay

    2016-02-01

    The oldest refinery and the major petrochemical complexes of Mexico are located in the lower reach of the Coatzacoalcos River, considered the most polluted coastal area of Mexico. A (210)Pb-dated sediment core, from the continental shelf of the Coatzacoalcos River, was studied to assess the contamination impact by the oil industry in the southern Gulf of Mexico. The sedimentary record showed the prevalence of petrogenic PAHs between 1950s and 1970s, a period during which waste discharges from the oil industry were not regulated. Later on, sediments exhibited higher contents of pyrogenic PAHs, attributed to the incineration of petrochemical industry wastes and recurrent wildfires in open dumpsites at the nearby swamps. The total concentration of the 16 EPA-priority PAHs indicated low levels of contamination (1000 ng g(-1)) during the late 1970s, most likely due to the major oil spill produced by the blowout of the Ixtoc-I offshore oil rig in deep waters of the southwestern Gulf of Mexico. Most of the PAH congeners did not show defined temporal trends but, according to a Factor Analysis, apparently have a common origin, probably waste released from the nearby oil industry. The only exceptions were the pyrogenic benzo(b)fluoranthene and benzo(a)pyrene, and the biogenic perylene, that showed increasing concentration trends with time, which we attributed to erosional input of contaminated soil from the catchment area. Our study confirmed chronic oil contamination in the Coatzacoalcos River coastal area from land based sources for more than 60 years (since 1950s). Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Front end embedded microprocessors in the JET computer-based control system, past, present and future

    International Nuclear Information System (INIS)

    Steed, C.A.; VanderBeken, H.; Browne, M.L.; Fullard, K.; Reed, K.; Tilley, M.; Schmidt, V.

    1987-01-01

    A brief history of the use of Front End Microprocessors in the JET Control and Data Acquisition System (CODAS) is presented. The present expansion in their use from 2 or 3 in 1983 to 27 now, is covered along with the reasoning behind their present usage. Finally, their future planned use in the area of remote handling is discussed and the authors present views on the use of front end processing in future large distributed control systems are presented

  1. Zoning and contamination rate of magnesium and heavy metals of iron, zinc and copper in the north and northwest aquifer of Khoy (Zourabad based on GIS and determining the contaminated source

    Directory of Open Access Journals (Sweden)

    Fariborz Khodadadi

    2015-04-01

    samples carried out in the chemistry laboratory of the University of Urmia. All water sampling procedures were performed based on standard protocols (SMEWW, 2010. The maximum concentration of heavy metal contamination of drinking water with EPA, WHO and national standards were compared. In this study, the chemical analysis of heavy metals, were used by graphite furnace atomic absorption spectrometry (at ppb for the elements Cu, Mg, Fe and Zn. Concentration of the heavy metals in acidified water samples (pH value of 2, using a flame atomic absorption spectrophotometer were analyzed. Discussion There are enormous amounts of Fe and magnesium in groundwater from the north and northwest Khoy plain, and the amount of Cu and zinc are in the normal range in water resources. The source of iron and magnesium in the groundwater of the study area is ultramafic and mafic rocks of the Khoy ophiolite complex. Weathering of ultramafic and mafic igneous rocks such as peridotite, olivine basalt, gabbro and pillow lava and then soil formation, high concentrations of the elements Mg and Fe were transferred to soil. Ferromagnesian olivine is formed Mg2+ and Fe2+ ions and tetrahedral silicon. If sufficient amount of Mg2+ and Fe3+ ions combine with silicon and oxygen, silicon into the soil, forms silicic acid (H4SiO4, or magnesium or iron smectite (clay minerals (Alexander et al., 2007. Several types of pyroxene are more stable than olivine. Orthopyroxene during weathering decompose into talc and smectite. Magnesite (MgCO3 is present in some serpentine soils. With respect to the empirical relationship (Kierczak et al., 2007 and based on temperature and rainfall, the study area with a drought index of 12.48 places in the category of semi-arid-cold climate between 10 and 19.9. Temperature changes in the condition cause weathering and leaching of serpentine soils, and subsequently can remove large amounts of magnesium. Weathering and leaching serpentine soils, releases immediately magnesium and

  2. Stochastic approach to municipal solid waste landfill life based on the contaminant transit time modeling using the Monte Carlo (MC) simulation

    International Nuclear Information System (INIS)

    Bieda, Bogusław

    2013-01-01

    The paper is concerned with application and benefits of MC simulation proposed for estimating the life of a modern municipal solid waste (MSW) landfill. The software Crystal Ball® (CB), simulation program that helps analyze the uncertainties associated with Microsoft® Excel models by MC simulation, was proposed to calculate the transit time contaminants in porous media. The transport of contaminants in soil is represented by the one-dimensional (1D) form of the advection–dispersion equation (ADE). The computer program CONTRANS written in MATLAB language is foundation to simulate and estimate the thickness of landfill compacted clay liner. In order to simplify the task of determining the uncertainty of parameters by the MC simulation, the parameters corresponding to the expression Z2 taken from this program were used for the study. The tested parameters are: hydraulic gradient (HG), hydraulic conductivity (HC), porosity (POROS), linear thickness (TH) and diffusion coefficient (EDC). The principal output report provided by CB and presented in the study consists of the frequency chart, percentiles summary and statistics summary. Additional CB options provide a sensitivity analysis with tornado diagrams. The data that was used include available published figures as well as data concerning the Mittal Steel Poland (MSP) S.A. in Kraków, Poland. This paper discusses the results and show that the presented approach is applicable for any MSW landfill compacted clay liner thickness design. -- Highlights: ► Numerical simulation of waste in porous media is proposed. ► Statistic outputs based on correct assumptions about probability distribution are presented. ► The benefits of a MC simulation are examined. ► The uniform probability distribution is studied. ► I report a useful tool applied to determine the life of a modern MSW landfill.

  3. Stochastic approach to municipal solid waste landfill life based on the contaminant transit time modeling using the Monte Carlo (MC) simulation

    Energy Technology Data Exchange (ETDEWEB)

    Bieda, Boguslaw, E-mail: bbieda@zarz.agh.edu.pl

    2013-01-01

    The paper is concerned with application and benefits of MC simulation proposed for estimating the life of a modern municipal solid waste (MSW) landfill. The software Crystal Ball Registered-Sign (CB), simulation program that helps analyze the uncertainties associated with Microsoft Registered-Sign Excel models by MC simulation, was proposed to calculate the transit time contaminants in porous media. The transport of contaminants in soil is represented by the one-dimensional (1D) form of the advection-dispersion equation (ADE). The computer program CONTRANS written in MATLAB language is foundation to simulate and estimate the thickness of landfill compacted clay liner. In order to simplify the task of determining the uncertainty of parameters by the MC simulation, the parameters corresponding to the expression Z2 taken from this program were used for the study. The tested parameters are: hydraulic gradient (HG), hydraulic conductivity (HC), porosity (POROS), linear thickness (TH) and diffusion coefficient (EDC). The principal output report provided by CB and presented in the study consists of the frequency chart, percentiles summary and statistics summary. Additional CB options provide a sensitivity analysis with tornado diagrams. The data that was used include available published figures as well as data concerning the Mittal Steel Poland (MSP) S.A. in Krakow, Poland. This paper discusses the results and show that the presented approach is applicable for any MSW landfill compacted clay liner thickness design. -- Highlights: Black-Right-Pointing-Pointer Numerical simulation of waste in porous media is proposed. Black-Right-Pointing-Pointer Statistic outputs based on correct assumptions about probability distribution are presented. Black-Right-Pointing-Pointer The benefits of a MC simulation are examined. Black-Right-Pointing-Pointer The uniform probability distribution is studied. Black-Right-Pointing-Pointer I report a useful tool applied to determine the life of a

  4. Estimation of the future nuclear power research in Romania, based on the present Cernavoda NPP evolution

    International Nuclear Information System (INIS)

    Dumitrache, Ion

    2001-01-01

    For more than four decades, the electric power needs of Romania were evaluated on the basis of the State Plan for Economic Development. To identify the optimal solution, the 'least price per produced MWh' was practically the only criterion. Now, there is no convincing estimation of the future economic development and at least two additional criteria play a significant role, 'the safety in the supply of the needed electric power', and 'the need of limiting the environmental impact of electricity generation'. The analysis dedicated to evaluation of future electric power solutions must take into account several features of the present situation. There are no available internal funds to finance the construction of new generating units of the order of several hundreds of MW. Even the so-called 'refurbishing' of the existing thermal power plants is based on foreign loan. In the 2000 year, about 80 electricity generation units reached 30 years of operation, i.e., the design life. Other thermal power plants proved very modest performances during 15-20 years of operation. Consequently, the future of almost 100 generating units is either in shutdown + decommissioning or shutdown + modernization situation. The Government analyzed the situation and decided to continue the completion of the Cernavoda NPP. The Unit 2 will be commissioned in a couple of years, and there is a schedule of negotiations relating the future of the Unit 3. After almost five years of successful operation of the Unit 1, the collaboration between RDT Institutes and NPP has clear features. Based on the experience related to this collaboration and taking into account the evolution of the Cernavoda NPP, we estimated that five research domains have significant chances to obtain a stable (and, hopefully, consistent) financial support. 1. Nuclear Safety, in particular Accident Analysis. As the Government re-iterated the firm decision to meet the conditions required for European integration, most of the nuclear

  5. Laryngeal giant cell tumour presenting as a tongue base lesion causing severe dysphagia

    Directory of Open Access Journals (Sweden)

    Mohd Razi M. Saud, MBBS

    2018-04-01

    Full Text Available الملخص: أورام الخلايا العملاقة هي آفات حميدة وغير مألوفة تظهر في الحنجرة. قد يصاب المريض بصعوبة في البلع، وبحة في الصوت وتورم في الجهة الأمامية من الرقبة. أورام الخلايا العملاقة هي نادرة للغاية، وهناك حالات قليلة في الأدبيات المنشورة. نعرض لحالة إمرأة مسنة قدمت بصعوبة شديدة في البلع، وورم في قاعدة اللسان. أظهرت نتيجة الورم بأنه ورم الخلايا العملاقة في الحنجرة وتم علاجه بنجاح باستخدام المعالجة الكيميائية. Abstract: Giant cell tumours are benign lesions that are uncommonly found in the larynx. Patients with these tumours may present with dysphagia, hoarseness and anterior neck swelling. Giant cell tumours are extremely rare and only a few cases have been reported. We present a case of an elderly woman who presented with severe dysphagia and a mass at the base of her tongue. The mass was found to be a laryngeal giant cell tumour and was successfully treated with chemotherapy. الكلمات المفتاحية: أورام الخلايا العملاقة, الحنجرة, صعوبة البلع, دينوسوماب, المعالجة الكيميائية, Keywords: Chemotherapy, Denosumab, Dysphagia, Giant cell tumour, Larynx

  6. Prediction of the effects of soil-based countermeasures on soil solution chemistry of soils contaminated with radiocesium using the hydrogeochemical code PHREEQC.

    Science.gov (United States)

    Hormann, Volker; Kirchner, Gerald

    2002-04-22

    For agriculturally used areas, which are contaminated by the debris from a nuclear accident, the use of chemical amendmends (e.g. potassium chloride and lime) is among the most common soil-based countermeasures. These countermeasures are intended to reduce the plant uptake of radionuclides (mainly 137Cs and 90Sr) by competitive inhibition by chemically similar ions. So far, the impacts of countermeasures on soil solution composition - and thus, their effectiveness - have almost exclusively been established experimentally, since they depend on mineral composition and chemical characteristics of the soil affected. In this study, which focuses on caesium contamination, the well-established code PHREEQC was used as a geochemical model to calculate the changes in the ionic compositions of soil solutions, which result from the application of potassium or ammonium in batch equilibrium experiments. The simple ion exchange model used by PHREEQC was improved by taking into account selective sorption of Cs+, NH4+ and K+ by clay minerals. Calculations were performed with three different initial soil solution compositions, corresponding to particular soil types (loam, sand, peat). For loamy and sandy soils, our calculational results agree well with experimental data reported by Nisbet (Effectiveness of soil-based countermeasures six months and one year after contamination of five diverse soil types with caesium-134 and strontium-90. Contract Report NRPB-M546, National Radiation Protection Board, Chilton, 1995.). For peat, discrepancies were found indicating that for organic soils a reliable set of exchange constants of the relevant cations still has to be determined experimentally. For cesium, however, these discrepancies almost disappeared if selective sites were assumed to be inaccessible. Additionally, results of sensitivity analyses are presented by which the influence of the main soil parameters on Cs+ concentrations in solution after soil treatment has been systematically

  7. Screening-level exposure-based prioritization to identify potential POPs, vPvBs and planetary boundary threats among Arctic contaminants

    Directory of Open Access Journals (Sweden)

    Efstathios Reppas-Chrysovitsinos

    2017-06-01

    Full Text Available A report that reviews Arctic contaminants that are not currently regulated as persistent organic pollutants (POPs under international treaties was recently published by the Arctic Monitoring and Assessment Programme (AMAP. We evaluated 464 individual chemicals mentioned in the AMAP report according to hazard profiles for POPs, very persistent and very bioaccumulative (vPvB chemicals, and two novel and distinct hazard profiles we derived from the planetary boundary threat framework. The two planetary boundary threat profiles assign high priority to chemicals that will be mobile and poorly reversible environmental contaminants. Utilizing persistence as a proxy for poor reversibility, we defined two exposure-based hazard profiles; airborne persistent contaminants (APCs and waterborne persistent contaminants (WPCs that are potential planetary boundary threats. We used in silico estimates of physicochemical properties and multimedia models to calculate hazard metrics for persistence, bioaccumulation and long-range transport potential, then we synthesized this information into four exposure-based hazard scores of the potential of each AMAP chemical to fit each of the POP, vPvB, APC and WPC exposure-based hazard profiles. As an alternative to adopting a “bright line” score that represented cause for concern, we scored the AMAP chemicals by benchmarking against a reference set of 148 known and relatively well-studied contaminants and expressed their exposure-based hazard scores as percentile ranks against the scores of the reference set chemicals. Our results show that scores in the four exposure-based hazard profiles provide complementary information about the potential environmental exposure-based hazards of the AMAP chemicals. Our POP, vPvB, APC and WPC exposure-based hazard scores identify high priority chemicals for further study from among the AMAP contaminants.

  8. Dermatitis herpetiformis – diagnostic difficulties based on the presentation of own cases

    Directory of Open Access Journals (Sweden)

    Katarzyna Łoza

    2014-03-01

    Full Text Available Introduction . Dermatitis herpetiformis (Duhring disease is an autoimmune blistering subepidermal dermatosis characterized by pruritic polymorphic skin eruption accompanied by a clinically asymptomatic gluten-sensitive enteropathy. The etiopathogenesis of the disease is associated with the presence of antibodies against tissue and epidermal transglutaminase. Diagnosis is based on direct immunopathological examination in which granular IgA deposits on the top of dermal papillae are detected. Sulfones are effective in the therapy of skin changes. Objective . The aim of the study is to present difficulties in evaluation of clinical picture, diagnosis and treatment, and monitoring the safety of the therapy in Duhring disease on the basis of three own cases. Case report . Case 1. 37-year-old patient. Itchy skin lesions occurred in mid-2012 and have been treated until now with antihistamines and local corticosteroids without improvement. The diagnosis of dermatitis herpetiformis was established on the basis of direct immunopathology test. Treated with gluten-free diet and dapsone 100 mg/day with improvement. Case 2. 62-year-old patient, in whom the first itchy eruption appeared in October 2012. Treated with antihistamines and topical corticosteroids without improvement. In laboratory examinations elevated level of IgE and triglycerides was found. Histopathological and immunological examinations confirmed the diagnosis of dermatitis herpetiformis. Treated with gluten-free diet and dapsone 150 mg/day with improvement. Case 3. 58-year-old patient. The first changes of typical morphology appeared about 2 years ago. The patient was treated with antihistamines and corticosteroids without improvement. Laboratory tests confirmed the diagnosis of Duhring disease. The introduction of gluten-free diet and dapsone 100 mg/day caused regression of skin changes. Conclusions . Our cases, treated for a long time as eczematous changes, despite the lack of improvement

  9. ACCESSING FEDERAL DATA BASES FOR CONTAMINATED SITE CLEAN-UP TECHNOLOGIES

    Science.gov (United States)

    The Federal Remediation Technologies Roundtable (Roundtable) eveloped this publication to provide information on accessing Federal data bases that contain data on innovative remediation technologies. The Roundtable includes representatives from the Department of Defense (DoD), En...

  10. Risk-Based Management of Contaminated Groundwater: The Role of Geologic Heterogeneity, Exposure and Cancer Risk in Determining the Performance of Aquifer Remediation

    International Nuclear Information System (INIS)

    Maxwell, R.M.; Carle, S.F.; Tompson, A.F.B.

    2000-01-01

    The effectiveness of aquifer remediation is typically expressed in terms of a reduction in contaminant concentrations relative to a regulated maximum contaminant level (MCL), and is usually confined by sparse monitoring data and/or simple model calculations. Here, the effectiveness of remediation is examined from a risk-based perspective that goes beyond the traditional MCL concept. A methodology is employed to evaluate the health risk to individuals exposed to contaminated household water that is produced from groundwater. This approach explicitly accounts for differences in risk arising from variability in individual physiology and water use, the uncertainty in estimating chemical carcinogenesis for different individuals, and the uncertainties and variability in contaminant concentrations within groundwater. A hypothetical contamination scenario is developed as a case study in a saturated, alluvial aquifer underlying a real Superfund site. A baseline (unremediated) human exposure and health risk scenario, as induced by contaminated groundwater pumped from this site, is predicted and compared with a similar estimate based upon pump-and-treat exposure intervention. The predicted reduction in risk in the remediation scenario is not an equitable one-that is, it is not uniform to all individuals within a population and varies according to the level of uncertainty in prediction. The importance of understanding the detailed hydrogeologic connections that are established in the heterogeneous geologic regime between the contaminated source, municipal receptors, and remediation wells, and its relationship to this uncertainty is demonstrated. Using two alternative pumping rates, we develop cost-benefit curves based upon reduced exposure and risk to different individuals within the population, under the presence of uncertainty

  11. Characterization of contamination, source and degradation of petroleum between upland and paddy fields based on geochemical characteristics and phospholipid fatty acids.

    Science.gov (United States)

    Zhang, Juan; Wang, Renqing; Du, Xiaoming; Li, Fasheng; Dai, Jiulan

    2012-01-01

    To evaluate contamination caused by petroleum, surface soil samples were collected from both upland and paddy fields along the irrigation canals in the Hunpu wastewater irrigation region in northeast China. N-alkanes, terpanes, steranes, and phospholipid fatty acids (PLFA) in the surface soil samples were analyzed. The aliphatic hydrocarbon concentration was highest in the samples obtained from the upland field near an operational oil well; it was lowest at I-3P where wastewater irrigation promoted the downward movement of hydrocarbons. The Hunpu region was found contaminated by heavy petroleum from oxic lacustrine fresh water or marine deltaic source rocks. Geochemical parameters also indicated significantly heavier contamination and degradation in the upland fields compared with the paddy fields. Principal component analysis based on PLFA showed various microbial communities between petroleum contaminated upland and paddy fields. Gram-negative bacteria indicated by 15:0, 3OH 12:0, and 16:1(9) were significantly higher in the paddy fields, whereas Gram-positive bacteria indicated by i16:0 and 18:1(9)c were significantly higher in the upland fields (p petroleum contamination. Poly-unsaturated PLFA (18:2omega6, 9; indicative of hydrocarbon-degrading bacteria and fungi) was also significantly elevated in the upland fields. This paper recommends more sensitive indicators of contamination and degradation of petroleum in soil. The results also provide guidelines on soil pollution control and remediation in the Hunpu region and other similar regions.

  12. Computer-Based English Language Testing in China: Present and Future

    Science.gov (United States)

    Yu, Guoxing; Zhang, Jing

    2017-01-01

    In this special issue on high-stakes English language testing in China, the two articles on computer-based testing (Jin & Yan; He & Min) highlight a number of consistent, ongoing challenges and concerns in the development and implementation of the nationwide IB-CET (Internet Based College English Test) and institutional computer-adaptive…

  13. The enhancement of simulation based learning exercises through formalised reflection, focus groups and group presentation

    NARCIS (Netherlands)

    Mawdesley, M.; Long, G.; Al-Jibouri, Saad H.S.; Scott, D.

    2011-01-01

    Computer based simulations and games can be useful tools in teaching aspects of construction project management that are not easily transmitted through traditional lecture based approaches. However, it can be difficult to quantify their utility and it is essential to ensure that students are

  14. Graphic Organizers or Graphic Overviews? Presentation Order Effects with Computer-Based Text

    Science.gov (United States)

    Shaw, Shana; Nihalani, Priya; Mayrath, Michael; Robinson, Daniel H.

    2012-01-01

    It has long been assumed that graphic organizers (GOs) should be presented to students following text as an organizer, rather than preceding text as an overview. Robinson et al. ("Educational Technology Research & Development," 51(4), 25-41, 2003) challenged this assumption by finding support for GOs as an overview. The present study further…

  15. Metagenome-based metabolic reconstruction reveals the ecophysiological function of Epsilonproteobacteria in a hydrocarbon-contaminated sulfidic aquifer

    Directory of Open Access Journals (Sweden)

    Andreas Hardy Keller

    2015-12-01

    Full Text Available The population genome of an uncultured bacterium assigned to the Campylobacterales (Epsilonproteobacteria was reconstructed from a metagenome dataset obtained by whole-genome shotgun pyrosequencing. Genomic DNA was extracted from a sulfate-reducing, m-xylene-mineralizing enrichment culture isolated from groundwater of a benzene-contaminated sulfidic aquifer. The identical epsilonproteobacterial phylotype has previously been detected in toluene- or benzene-mineralizing, sulfate-reducing consortia enriched from the same site. Previous stable isotope probing experiments with 13C6-labeled benzene suggested that this phylotype assimilates benzene-derived carbon in a syntrophic benzene-mineralizing consortium that uses sulfate as terminal electron acceptor. However, the type of energy metabolism and the ecophysiological function of this epsilonproteobacterium within aromatic hydrocarbon-degrading consortia and in the sulfidic aquifer are poorly understood.Annotation of the epsilonproteobacterial population genome suggests that the bacterium plays a key role in sulfur cycling as indicated by the presence of a sqr gene encoding a sulfide quinone oxidoreductase and psr genes encoding a polysulfide reductase. It may gain energy by using sulfide or hydrogen/formate as electron donors. Polysulfide, fumarate, as well as oxygen are potential electron acceptors. Auto- or mixotrophic carbon metabolism seems plausible since a complete reductive citric acid cycle was detected. Thus the bacterium can thrive in pristine groundwater as well as in hydrocarbon-contaminated aquifers. In hydrocarbon-contaminated sulfidic habitats, the epsilonproteobacterium may generate energy by coupling the oxidation of hydrogen or formate and highly abundant sulfide with the reduction of fumarate and/or polysulfide, accompanied by efficient assimilation of acetate produced during fermentation or incomplete oxidation of hydrocarbons. The highly efficient assimilation of acetate was

  16. Metagenome-Based Metabolic Reconstruction Reveals the Ecophysiological Function of Epsilonproteobacteria in a Hydrocarbon-Contaminated Sulfidic Aquifer.

    Science.gov (United States)

    Keller, Andreas H; Schleinitz, Kathleen M; Starke, Robert; Bertilsson, Stefan; Vogt, Carsten; Kleinsteuber, Sabine

    2015-01-01

    The population genome of an uncultured bacterium assigned to the Campylobacterales (Epsilonproteobacteria) was reconstructed from a metagenome dataset obtained by whole-genome shotgun pyrosequencing. Genomic DNA was extracted from a sulfate-reducing, m-xylene-mineralizing enrichment culture isolated from groundwater of a benzene-contaminated sulfidic aquifer. The identical epsilonproteobacterial phylotype has previously been detected in toluene- or benzene-mineralizing, sulfate-reducing consortia enriched from the same site. Previous stable isotope probing (SIP) experiments with (13)C6-labeled benzene suggested that this phylotype assimilates benzene-derived carbon in a syntrophic benzene-mineralizing consortium that uses sulfate as terminal electron acceptor. However, the type of energy metabolism and the ecophysiological function of this epsilonproteobacterium within aromatic hydrocarbon-degrading consortia and in the sulfidic aquifer are poorly understood. Annotation of the epsilonproteobacterial population genome suggests that the bacterium plays a key role in sulfur cycling as indicated by the presence of an sqr gene encoding a sulfide quinone oxidoreductase and psr genes encoding a polysulfide reductase. It may gain energy by using sulfide or hydrogen/formate as electron donors. Polysulfide, fumarate, as well as oxygen are potential electron acceptors. Auto- or mixotrophic carbon metabolism seems plausible since a complete reductive citric acid cycle was detected. Thus the bacterium can thrive in pristine groundwater as well as in hydrocarbon-contaminated aquifers. In hydrocarbon-contaminated sulfidic habitats, the epsilonproteobacterium may generate energy by coupling the oxidation of hydrogen or formate and highly abundant sulfide with the reduction of fumarate and/or polysulfide, accompanied by efficient assimilation of acetate produced during fermentation or incomplete oxidation of hydrocarbons. The highly efficient assimilation of acetate was recently

  17. Functional gene array-based analysis of microbial community structure in groundwaters with a gradient of contaminant levels

    Energy Technology Data Exchange (ETDEWEB)

    Waldron, P.J.; Wu, L.; Van Nostrand, J.D.; Schadt, C.W.; Watson, D.B.; Jardine, P.M.; Palumbo, A.V.; Hazen, T.C.; Zhou, J.

    2009-06-15

    To understand how contaminants affect microbial community diversity, heterogeneity, and functional structure, six groundwater monitoring wells from the Field Research Center of the U.S. Department of Energy Environmental Remediation Science Program (ERSP; Oak Ridge, TN), with a wide range of pH, nitrate, and heavy metal contamination were investigated. DNA from the groundwater community was analyzed with a functional gene array containing 2006 probes to detect genes involved in metal resistance, sulfate reduction, organic contaminant degradation, and carbon and nitrogen cycling. Microbial diversity decreased in relation to the contamination levels of the wells. Highly contaminated wells had lower gene diversity but greater signal intensity than the pristine well. The microbial composition was heterogeneous, with 17-70% overlap between different wells. Metal-resistant and metal-reducing microorganisms were detected in both contaminated and pristine wells, suggesting the potential for successful bioremediation of metal-contaminated groundwaters. In addition, results of Mantel tests and canonical correspondence analysis indicate that nitrate, sulfate, pH, uranium, and technetium have a significant (p < 0.05) effect on microbial community structure. This study provides an overall picture of microbial community structure in contaminated environments with functional gene arrays by showing that diversity and heterogeneity can vary greatly in relation to contamination.

  18. Removal of bulk contaminants from radioactive waste water at Bruce A using a clay based flocculent system

    International Nuclear Information System (INIS)

    Davloor, R.; Harper, B.

    2011-01-01

    implement a clay-based flocculation Pre-Treatment System. In-service since late 2000, the system has been able to reliably treat a broad range of contaminants in the waste water before being sent to the downstream ROS. This clay-based system is unique in its application; it is able to remove bulk oil and grease, suspended solids, and metal contaminants in a waste stream that contains a high amount of surfactants originating from the laundering of plastic suits (personal protective equipment for working in radioactive environments) and other waste waters from the station. The treated water from the PTS consistently meets the strict requirements for subsequent treatment by the system RO membranes. This paper describes the laboratory and pilot scale testing that led to the development of the process, as well as the full scale implementation of this unique Pre-Treatment System. (author)

  19. Removal of bulk contaminants from radioactive waste water at Bruce A using a clay based flocculent system

    Energy Technology Data Exchange (ETDEWEB)

    Davloor, R.; Harper, B. [Bruce Power, Tiverton, ON (Canada)

    2011-07-01

    implement a clay-based flocculation Pre-Treatment System. In-service since late 2000, the system has been able to reliably treat a broad range of contaminants in the waste water before being sent to the downstream ROS. This clay-based system is unique in its application; it is able to remove bulk oil and grease, suspended solids, and metal contaminants in a waste stream that contains a high amount of surfactants originating from the laundering of plastic suits (personal protective equipment for working in radioactive environments) and other waste waters from the station. The treated water from the PTS consistently meets the strict requirements for subsequent treatment by the system RO membranes. This paper describes the laboratory and pilot scale testing that led to the development of the process, as well as the full scale implementation of this unique Pre-Treatment System. (author)

  20. Light contamination

    International Nuclear Information System (INIS)

    Cepeda Pena, William Enrique

    1998-01-01

    The article tries on the wrong use of the artificial light, of the main problems of the light contamination, dispersion of the light, noxious effects of the light contamination, ecological effects, effects on the man's biological rhythm, economic effects and effects about the civic and vial security, among other topics

  1. Extension of the TAMSAT satellite-based rainfall monitoring over Africa and from 1983 to present

    OpenAIRE

    Tarnavsky, Elena; Grimes, David; Maidment, Ross; Black, Emily; Allan, Richard; Stringer, Marc; Chadwick, Robin; Kayitakire, Francois

    2014-01-01

    Tropical Applications of Meteorology Using Satellite Data and Ground-Based Observations (TAMSAT) rainfall monitoring products have been extended to provide spatially contiguous rainfall estimates across Africa. This has been achieved through a new, climatology-based calibration, which varies in both space and time. As a result, cumulative estimates of rainfall are now issued at the end of each 10-day period (dekad) at 4-km spatial resolution with pan-African coverage. The utility of the produ...

  2. In vivo microwave-based thermoacoustic tomography of rats (Conference Presentation)

    Science.gov (United States)

    Lin, Li; Zhou, Yong; Wang, Lihong V.

    2016-03-01

    Microwave-based thermoacoustic tomography (TAT), based on the measurement of ultrasonic waves induced by microwave pulses, can reveal tissue dielectric properties that may be closely related to the physiological and pathological status of the tissues. Using microwaves as the excitation source improved imaging depth because of their deep penetration into biological tissues. We demonstrate, for the first time, in vivo microwave-based thermoacoustic imaging in rats. The transducer is rotated around the rat in a full circle, providing a full two-dimensional view. Instead of a flat ultrasonic transducer, we used a virtual line detector based on a cylindrically focused transducer. A 3 GHz microwave source with 0.6 µs pulse width and an electromagnetically shielded transducer with 2.25 MHz central frequency provided clear cross-sectional images of the rat's body. The high imaging contrast, based on the tissue's rate of absorption, and the ultrasonically defined spatial resolution combine to reveal the spine, kidney, muscle, and other deeply seated anatomical features in the rat's abdominal cavity. This non-invasive and non-ionizing imaging modality achieved an imaging depth beyond 6 cm in the rat's tissue. Cancer diagnosis based on information about tissue properties from microwave band TAT can potentially be more accurate than has previously been achievable.

  3. Reducing viral contamination from finger pads: handwashing is more effective than alcohol-based hand disinfectants

    NARCIS (Netherlands)

    Tuladhar, E.; Hazeleger, W.C.; Koopmans, M.; Zwietering, M.H.; Duizer, E.

    2015-01-01

    Background - Hand hygiene is important for interrupting transmission of viruses through hands. Effectiveness of alcohol-based hand disinfectant has been shown for bacteria but their effectiveness in reducing transmission of viruses is ambiguous. Aim - To test efficacy of alcohol hand disinfectant

  4. A GIS-based vulnerability assessment of brine contamination to aquatic resources from oil and gas development in eastern Sheridan County, Montana.

    Science.gov (United States)

    Preston, Todd M; Chesley-Preston, Tara L; Thamke, Joanna N

    2014-02-15

    Water (brine) co-produced with oil in the Williston Basin is some of the most saline in the nation. The Prairie Pothole Region (PPR), characterized by glacial sediments and numerous wetlands, covers the northern and eastern portion of the Williston Basin. Sheridan County, Montana, lies within the PPR and has a documented history of brine contamination. Surface water and shallow groundwater in the PPR are saline and sulfate dominated while the deeper brines are much more saline and chloride dominated. A Contamination Index (CI), defined as the ratio of chloride concentration to specific conductance in a water sample, was developed by the Montana Bureau of Mines and Geology to delineate the magnitude of brine contamination in Sheridan County. Values >0.035 indicate contamination. Recently, the U.S. Geological Survey completed a county level geographic information system (GIS)-based vulnerability assessment of brine contamination to aquatic resources in the PPR of the Williston Basin based on the age and density of oil wells, number of wetlands, and stream length per county. To validate and better define this assessment, a similar approach was applied in eastern Sheridan County at a greater level of detail (the 2.59 km(2) Public Land Survey System section grid) and included surficial geology. Vulnerability assessment scores were calculated for the 780 modeled sections and these scores were divided into ten equal interval bins representing similar probabilities of contamination. Two surface water and two groundwater samples were collected from the section with the greatest acreage of Federal land in each bin. Nineteen of the forty water samples, and at least one water sample from seven of the ten selected sections, had CI values indicating contamination. Additionally, CI values generally increased with increasing vulnerability assessment score, with a stronger correlation for groundwater samples (R(2)=0.78) than surface water samples (R(2)=0.53). Copyright © 2013

  5. Use of the physiologically-based extraction test to assess the oral bioaccessibility of metals in vegetable plants grown in contaminated soil

    International Nuclear Information System (INIS)

    Intawongse, Marisa; Dean, John R.

    2008-01-01

    The oral bioaccessibility of metals in vegetable plants grown on contaminated soil was assessed. This was done using the physiologically-based extraction test (PBET) to simulate the human digestion of plant material. A range of vegetable plants, i.e. carrot, lettuce, radish and spinach, were grown on metal contaminated soil. After reaching maturity the plants were harvested and analysed for their total metal content (i.e. Cr, Cd, Cu, Fe, Mn, Mo, Ni, Pb and Zn) by inductively coupled plasma-mass spectrometry (ICP-MS). The plant samples were then subsequently extracted using an in vitro gastrointestinal approach or PBET to assess the likelihood of oral bioaccessibility if the material was consumed by humans. - Evaluation of a physiologically-based extraction test to assess the risk to humans of consuming contaminated vegetables

  6. Use of the physiologically-based extraction test to assess the oral bioaccessibility of metals in vegetable plants grown in contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Intawongse, Marisa [Biomolecular and Biomedical Research Centre, School of Applied Sciences, University of Northumbria at Newcastle, Ellison Building, Newcastle upon Tyne NE1 8ST (United Kingdom); Dean, John R. [Biomolecular and Biomedical Research Centre, School of Applied Sciences, University of Northumbria at Newcastle, Ellison Building, Newcastle upon Tyne NE1 8ST (United Kingdom)], E-mail: john.dean@unn.ac.uk

    2008-03-15

    The oral bioaccessibility of metals in vegetable plants grown on contaminated soil was assessed. This was done using the physiologically-based extraction test (PBET) to simulate the human digestion of plant material. A range of vegetable plants, i.e. carrot, lettuce, radish and spinach, were grown on metal contaminated soil. After reaching maturity the plants were harvested and analysed for their total metal content (i.e. Cr, Cd, Cu, Fe, Mn, Mo, Ni, Pb and Zn) by inductively coupled plasma-mass spectrometry (ICP-MS). The plant samples were then subsequently extracted using an in vitro gastrointestinal approach or PBET to assess the likelihood of oral bioaccessibility if the material was consumed by humans. - Evaluation of a physiologically-based extraction test to assess the risk to humans of consuming contaminated vegetables.

  7. Leak detection systems for VVER units based on leak before break concept. PowerPoint presentation

    International Nuclear Information System (INIS)

    Matal, Oldrich

    2010-01-01

    To comply with international standards, independent leak monitoring systems should be installed based on the monitoring of different physical parameters capable of detecting any small leak within one hour from the start of the leak. Such leak detection systems are based mainly on acoustic emission monitoring, humidity monitoring and/or radiation monitoring. Advanced systems integrate the monitoring of different physical parameters into one integrated leak detection system. The Integrated Leak Detection System (ILDS) for NPP Metsamor is described. This system consists of three independent leak detection subsystems, viz. LEMOP (LEak MOnitoring of Pipelines) based on acoustic emission monitoring, HUMOS (HUmidity MOnitoring System) based on humidity monitoring, and RAMOS (RAdiation MOnitoring System) based on radiation monitoring). The Integrated Leak Detection System (ILDS) collects data from the three systems, performs data evaluation, data storage, generates alarms and provides a user interface for the whole system including all subsystems. An example of DiagAssist user interface in the ILDS system in the pictorial form. (P.A.)

  8. Fixed-base recycling of contaminated metals in the commercial market

    International Nuclear Information System (INIS)

    Loiselle, V.

    1993-01-01

    Since the establishment of the first fixed-base commercial decontamination facility in 1982, commercial processors have cleaned and recycled more than 120 million lb of metals for productive reuse. This represents enough metal to duplicate the Eiffel Tower eight times. This paper examines the economic conditions that led to the foundation of this industry and the types of decontamination technology that have been successfully employed by the processors

  9. Kola Fjord radioactive contamination in the vicinity of the nuclear icebreakers fleet base

    International Nuclear Information System (INIS)

    Namjatov, A.

    1995-01-01

    The civil nuclear icebreakers have been based at the enterprise ''Atomflot'' in the Kola Bay for more than 30 years. In this paper the effects of nuclear discards from these ships on the ecosystem in the region have been stipulated. It is concluded that the estimated individual dose to man in the area is 1.7 to 4.1 x 10 -4 μSv/year

  10. Fuzzy net present valuation based on risk assessment of Malaysian infrastructure

    Science.gov (United States)

    Shaffie, Siti Salihah; Jaaman, Saiful Hafizah; Mohamad, Daud

    2017-04-01

    In recent years, built-operate-transfer (BOT) projects have profoundly been accepted under project financing for infrastructure developments in many countries. It requires high financing and involves complex mutual risk. The assessment of the risks is vital to avert huge financial loss. Net present value is widely applied to BOT project where the uncertainties in cash flows are deemed to be deterministic values. This study proposed a fuzzy net present value model taking consideration the assessment of risks from the BOT project. The proposed model is adopted to provide more flexible net present valuation of the project. It is shown and proven that the improved fuzzy cash flow model will provide a valuation that is closed to the real value of the project.

  11. Thermal runaway reaction hazards and mechanisms of hydroxylamine with acid/base contaminants

    International Nuclear Information System (INIS)

    Wei Chunyang; Saraf, Sanjeev R.; Rogers, William J.; Sam Mannan, M.

    2004-01-01

    Hydroxylamine (HA) has been involved in two incidents since 1999 because of its thermal instability and incompatibility. In this study, thermal runaway reactions of hydroxylamine with various concentrations of KOH and HCl were studied using the reactive system screening tool (RSST) and automatic pressure tracking adiabatic calorimeter (APTAC). The thermokinetic data, such as onset temperature, heat of reaction, maximum self-heat rate, maximum pressure rate, and non-condensable gas pressure, were compared with those of hydroxylamine solution without added impurity. Our study shows that the thermal decomposition behavior of hydroxylamine is affected by the presence of acid/base, and mixing of hydroxylamine with acid/base may cause thermal decomposition at lower temperatures. Different decomposition pathways can be initiated by hydrogen ion and hydroxide ion. The decomposition mechanisms of hydroxylamine in alkaline and acidic solutions are proposed based on the products, information from the literature, and quantum mechanical calculations. The experimental results are discussed in terms of the proposed reaction mechanisms

  12. Contamination of apple orchard soils and fruit trees with copper-based fungicides: sampling aspects.

    Science.gov (United States)

    Wang, Quanying; Liu, Jingshuang; Liu, Qiang

    2015-01-01

    Accumulations of copper in orchard soils and fruit trees due to the application of Cu-based fungicides have become research hotspots. However, information about the sampling strategies, which can affect the accuracy of the following research results, is lacking. This study aimed to determine some sampling considerations when Cu accumulations in the soils and fruit trees of apple orchards are studied. The study was conducted in three apple orchards from different sites. Each orchard included two different histories of Cu-based fungicides usage, varying from 3 to 28 years. Soil samples were collected from different locations varying with the distances from tree trunk to the canopy drip line. Fruits and leaves from the middle heights of tree canopy at two locations (outer canopy and inner canopy) were collected. The variation in total soil Cu concentrations between orchards was much greater than the variation within orchards. Total soil Cu concentrations had a tendency to increase with the increasing history of Cu-based fungicides usage. Moreover, total soil Cu concentrations had the lowest values at the canopy drip line, while the highest values were found at the half distances between the trunk and the canopy drip line. Additionally, Cu concentrations of leaves and fruits from the outer parts of the canopy were significantly higher than from the inner parts. Depending on the findings of this study, not only the between-orchard variation but also the within-orchard variation should be taken into consideration when conducting future soil and tree samplings in apple orchards.

  13. Application of different measures of bioavailability to support the derivation of risk-based remedial benchmarks for PHC-contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, G. [Stantec Consulting Ltd., Surrey, BC (Canada)

    2009-07-01

    Risk estimates and exposure scenarios hardly ever take into consideration site-specific bioavailability of contaminants. Risk assessors frequently adopt the assumption that a contaminant in soils is 100 percent bioavailable, resulting in an overestimation of the risks associated with contamination. Remedial targets or benchmarks derived in light of this assumption are needlessly low and might be technically unattainable or prohibitive in terms of cost. This presentation discussed a research project whose goal was to develop a tool kit to measure or determine site-specific bioavailability of contaminants (PHCs) in soils to ecological receptors. Tools that were discussed included: biological measures such as toxicity tests, contaminant residues in tissues, and bioaccumulation tests. Chemical measures such as bioaccessibility tests and other biomimetic devices (SPMDs), biotic ligand modeling, and chemical extractions were also presented. Preliminary investigation results were provided. Other topics that were discussed included: single-species toxicity tests; preliminary comparisons; the site; bioaccumulation; and toxicity to earthworms. It was concluded that total soil and water-extractable concentrations did not correlate well with toxicity. tabs., figs.

  14. Lecturers, Students and Community Members Sharing the Responsibility of Assessing Project-Based Poster Presentations

    Science.gov (United States)

    Beylefeld, A. A.; Joubert, G.; Jama, M. P.; de Klerk, B.

    2003-01-01

    Active participation in the process of learning rather than transmission of information is prominent in modern higher education contexts. In alignment with this trend, traditional modes of assessment, based on the "transmission model", are increasingly replaced or supplemented by more authentic forms of assessment. Authentic assessment "measures"…

  15. MitBASE : a comprehensive and integrated mitochondrial DNA database. The present status

    NARCIS (Netherlands)

    Attimonelli, M.; Altamura, N.; Benne, R.; Brennicke, A.; Cooper, J. M.; D'Elia, D.; Montalvo, A.; Pinto, B.; de Robertis, M.; Golik, P.; Knoop, V.; Lanave, C.; Lazowska, J.; Licciulli, F.; Malladi, B. S.; Memeo, F.; Monnerot, M.; Pasimeni, R.; Pilbout, S.; Schapira, A. H.; Sloof, P.; Saccone, C.

    2000-01-01

    MitBASE is an integrated and comprehensive database of mitochondrial DNA data which collects, under a single interface, databases for Plant, Vertebrate, Invertebrate, Human, Protist and Fungal mtDNA and a Pilot database on nuclear genes involved in mitochondrial biogenesis in Saccharomyces

  16. A Study on the Learning Efficiency of Multimedia-Presented, Computer-Based Science Information

    Science.gov (United States)

    Guan, Ying-Hua

    2009-01-01

    This study investigated the effects of multimedia presentations on the efficiency of learning scientific information (i.e. information on basic anatomy of human brains and their functions, the definition of cognitive psychology, and the structure of human memory). Experiment 1 investigated whether the modality effect could be observed when the…

  17. Make Slides Great Again: Evidence-based Approaches for Presenting Psychological Data

    NARCIS (Netherlands)

    Zawadzki, Stephanie; Zawadzki, TJ

    2017-01-01

    Workshop information: Science communication is not just a buzzword - it's a revolution in how we present our work to the public, our students, and each other. Given the same information, good powerpoint design alone has been shown to significantly improve audience comprehension, memory, and learning

  18. Late presentation to HIV testing is overestimated when based on the consensus definition.

    Science.gov (United States)

    Sasse, A; Florence, E; Pharris, A; De Wit, S; Lacor, P; Van Beckhoven, D; Deblonde, J; Delforge, M-L; Fransen, K; Goffard, J-C; Legrand, J-C; Moutschen, M; Piérard, D; Ruelle, J; Vaira, D; Vandercam, B; Van Ranst, M; Van Wijngaerden, E; Vandekerckhove, L; Verhofstede, C

    2016-03-01

    In 2011, a consensus was reached defining "late presenters" (LPs) as individuals presenting for care with a CD4 count account. Case surveillance data for newly diagnosed patients in Belgium in 1998-2012 were analysed, including CD4 count at diagnosis, the presence of AIDS-defining events, and recent infections (definition. Secondly, LPs were reclassified as "nonlate" if infections were reported as recent. A total of 7949 HIV diagnoses were included in the study. Recent infections were increasingly reported over time, accounting for 8.2% of new infections in 1998 and 37.5% in 2012. The consideration of clinical stage significantly modified the proportion of LPs: 18.2% of men who have sex with men (MSM) diagnosed in 2012 would be classified as LPs instead of 30.9% using the consensus definition (P definition. The impact of transient CD4 count on late presentation estimates should be assessed and, if relevant, the introduction of clinical stage in the definition of late presentation should be considered. © 2015 British HIV Association.

  19. Present status of transport code development based on Monte Carlo method

    International Nuclear Information System (INIS)

    Nakagawa, Masayuki

    1985-01-01

    The present status of development in Monte Carlo code is briefly reviewed. The main items are the followings; Application fields, Methods used in Monte Carlo code (geometry spectification, nuclear data, estimator and variance reduction technique) and unfinished works, Typical Monte Carlo codes and Merits of continuous energy Monte Carlo code. (author)

  20. The antimicrobial effect of spice-based marinades against Campylobacter jejuni on contaminated fresh broiler wings.

    Science.gov (United States)

    Zakarienė, Gintarė; Rokaitytė, Anita; Ramonaitė, Sigita; Novoslavskij, Aleksandr; Mulkytė, Kristina; Zaborskienė, Gintarė; Malakauskas, Mindaugas

    2015-03-01

    The antimicrobial effect of spice-based marinades against Campylobacter jejuni on inoculated fresh broiler wings was investigated. Experiments were carried out with 1 strain of C. jejuni and 6 marinades. Four experimental marinades were composed for the study and contained spices (thyme, rosemary, basil, marjoram, and so on) and different combination of bioactive compounds. Two marinades were commercial and contained spices (black pepper, sweet red pepper, and so on) and chemical additives (monosodium glutamate, sodium diacetate, calcium lactate), 1 commercial marinade was also enriched with bioactive compounds (linalool, cinnamaldehyde, lactic acid). Total aerobic bacterial count was examined to estimate the possible effect of tested marinades on the shelf-life of marinated broiler wings. Study revealed that thyme-based marinade was the most effective against C. jejuni on broiler wings and reduced the numbers of campylobacters by 1.04 log colony forming unit (CFU)/g (P ≤ 0.05) during storage for 168 h at 4 °C temperature. Moreover, it was more effective against C. jejuni than commercial marinade with 0.47 log CFU/g (P ≤ 0.05) reduction effect. Both experimental and commercial marinades had very similar effect on the total aerobic bacterial count. Although experimental and commercial marinades had different effect on pH of broiler wings, this parameter did not show a major impact on the antimicrobial effect of tested marinades (P ≥ 0.05). Our study shows that experimental natural thyme-based marinade can reduce numbers of C. jejuni more effectively than tested commercial marinades. © 2015 Institute of Food Technologists®

  1. Assessing the bioavailability and risk from metal-contaminated ...

    Science.gov (United States)

    Exposure to contaminated soil and dust is an important pathway in human health risk assessment. Physical and chemical characteristics, as well as biological factors, determine the bioaccessibility/bioavailability of soil and dust contaminants. Within a single sample, contamination may arise from multiple sources of toxic elements that may exist as different forms (species) which impact bioavailability. In turn, the bioaccessibility/bioavailability of soil and dust contaminants has a direct impact on human health risk assessment and risk management practices. Novel research efforts focusing on development and application of in vitro and in vivo methods to measure the bioaccessibility/bioavailability of metal contaminated soils have advanced in the past few years. The objective of this workshop was to focus on recent developments in assessing the bioaccessibility/bioavailability of arsenic contaminated soils, metal contamination in urban residences in Canada and potential children’s exposures to toxic elements in house dust, a community-based study known as the West Oakland Residential Lead Assessment , studies of the bioavailability of soil cadmium, chromium, nickel and mercury and human exposures to contaminated Brownfield soils. These presentations covered issues related to human health and bioavailability along with the most recent studies on community participation in assessing metal contamination, studies of exposures to residential contamination, and

  2. Evaluating Potential Human Health Risks Associated with the Development of Utility-Scale Solar Energy Facilities on Contaminated Sites

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, J. -J. [Argonne National Lab. (ANL), Argonne, IL (United States); Chang, Y. -S. [Argonne National Lab. (ANL), Argonne, IL (United States); Hartmann, H. [Argonne National Lab. (ANL), Argonne, IL (United States); Wescott, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Kygeris, C. [Indiana Univ. of Pennsylvania, PA (United States)

    2013-09-01

    This report presents a general methodology for obtaining preliminary estimates of the potential human health risks associated with developing a utility-scale solar energy facility on a contaminated site, based on potential exposures to contaminants in soils (including transport of those contaminants into the air).

  3. A Neural Networks Based Operation Guidance System for Procedure Presentation and Validation

    International Nuclear Information System (INIS)

    Seung, Kun Mo; Lee, Seung Jun; Seong, Poong Hyun

    2006-01-01

    In this paper, a neural network based operator support system is proposed to reduce operator's errors in abnormal situations in nuclear power plants (NPPs). There are many complicated situations, in which regular and suitable operations should be done by operators accordingly. In order to regulate and validate operators' operations, it is necessary to develop an operator support system which includes computer based procedures with the functions for operation validation. Many computerized procedures systems (CPS) have been recently developed. Focusing on the human machine interface (HMI) design and procedures' computerization, most of CPSs used various methodologies to enhance system's convenience, reliability and accessibility. Other than only showing procedures, the proposed system integrates a simple CPS and an operation validation system (OVS) by using artificial neural network (ANN) for operational permission and quantitative evaluation

  4. Present state of condition based maintenance (CBM) and its future problem

    International Nuclear Information System (INIS)

    Hashimoto, Satoshi; Nogami, Takeki; Sugiyama, Naoki

    2008-01-01

    New inspection system of the nuclear power plant will be introduced from 2008. In this feature, eleven experts from electric utilities, venders and academia described their views or activities about Condition Based Maintenance (CBM) with a new inspection system attracting attention. These are titled as 'Electric utilities view on CBM and its technology', Deployment results of developed CBM technologies', 'Valve diagnostic analysis support system with wireless technology applied', 'Portable vibration checker', 'Tribology diagnosis with no overhaul', 'Infrared thermograph diagnosis', 'Pipewall thinning inspection and management' and, in addition, the US trend and also the development trend of the CBM advancement technology in the vender and university. CBM technology will be introduced step-by-step and contribute to establish reliability based maintenance. (T. Tanaka)

  5. ALI and DAC for transuranic elements based on the metabolic data presented in ICRP Publication 48

    International Nuclear Information System (INIS)

    Togawa, Orihiko; Yamaguchi, Yukichi; Homma, Toshimitsu

    1987-07-01

    The recently published ICRP report, ICRP Publication 48, presents the new metabolic data of some transuranic elements, compared with those employed in the calculation of ALI and DAC in ICRP Publication 30. Values of ALI and DAC for 72 radionuclides were calculated using the metabolic data presented in the Publication 48. The calculation was performed by a computer code system DOSDAC, which can systematically calculate ALI and DAC by the same method as that described in the Publication 30. The calculated values of ALI and DAC were tabulated in the same format as that of the supplements to the Publication 30. For the convenience of using in the dose assessment, also given are values of committed effective dose equivalent per intake of unit activity. It is expected that these values will be applied to the radiation protection purposes. (author)

  6. Optical coherence tomography based microangiography: A tool good for dermatology applications (Conference Presentation)

    Science.gov (United States)

    Wang, Ruikang K.; Baran, Utku; Choi, Woo J.

    2016-02-01

    Optical coherence tomography (OCT) based microangiography (OMAG) is a new imaging technique enabling the visualization of blood flow within microcirculatory tissue beds in vivo with high resolution. In this talk, the concept and advantages of OMAG will be discussed and its potential clinical applications in the dermatology will be shown, demonstrating its usefulness in the clinical monitoring and therapeutic treatment of various skin pathologies, e.g. acne, port wine stain and wound healing.

  7. Design of a sensitive grating-based phase contrast mammography prototype (Conference Presentation)

    Science.gov (United States)

    Arboleda Clavijo, Carolina; Wang, Zhentian; Köhler, Thomas; van Stevendaal, Udo; Martens, Gerhard; Bartels, Matthias; Villanueva-Perez, Pablo; Roessl, Ewald; Stampanoni, Marco

    2017-03-01

    Grating-based phase contrast mammography can help facilitate breast cancer diagnosis, as several research works have demonstrated. To translate this technique to the clinics, it has to be adapted to cover a large field of view within a limited exposure time and with a clinically acceptable radiation dose. This indicates that a straightforward approach would be to install a grating interferometer (GI) into a commercial mammography device. We developed a wave propagation based optimization method to select the most convenient GI designs in terms of phase and dark-field sensitivities for the Philips Microdose Mammography (PMM) setup. The phase sensitivity was defined as the minimum detectable breast tissue electron density gradient, whereas the dark-field sensitivity was defined as its corresponding signal-to-noise Ratio (SNR). To be able to derive sample-dependent sensitivity metrics, a visibility reduction model for breast tissue was formulated, based on previous research works on the dark-field signal and utilizing available Ultra-Small-Angle X-ray Scattering (USAXS) data and the outcomes of measurements on formalin-fixed breast tissue specimens carried out in tube-based grating interferometers. The results of this optimization indicate the optimal scenarios for each metric are different and fundamentally depend on the noise behavior of the signals and the visibility reduction trend with respect to the system autocorrelation length. In addition, since the inter-grating distance is constrained by the space available between the breast support and the detector, the best way we have to improve sensitivity is to count on a small G2 pitch.

  8. Plasma-based determination of inorganic contaminants in waste of electric and electronic equipment after microwave-induced combustion

    Energy Technology Data Exchange (ETDEWEB)

    Mello, Paola A.; Diehl, Lisarb O.; Oliveira, Jussiane S.S.; Muller, Edson I. [Departamento de Química, Universidade Federal de Santa Maria, Av. Roraima, 1000, 97105-900, Santa Maria (Brazil); Mesko, Marcia F. [Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Capão do Leão, 96900-010 Pelotas, RS (Brazil); Flores, Erico M.M., E-mail: ericommf@gmail.com [Departamento de Química, Universidade Federal de Santa Maria, Av. Roraima, 1000, 97105-900, Santa Maria (Brazil)

    2015-03-01

    A systematic study was performed for the determination of inorganic contaminants in polymeric waste from electrical and electronic equipment (EEE) for achieving an efficient digestion to minimize interferences in determination using plasma-based techniques. The determination of As, Br, Cd, Co, Cr, Cu, Ni, Pb, Sb, and Zn by inductively coupled plasma mass spectrometry (ICP-MS) and also by inductively coupled plasma optical emission spectrometry (ICP OES) was carried out after digestion using microwave-induced combustion (MIC). Arsenic and Hg were determined by flow-injection chemical vapor generation inductively coupled plasma mass spectrometry (FI-CVG-ICP-MS). Dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS) with ammonia was also used for Cr determination. The suitability of MIC for digestion of sample masses up to 400 mg was demonstrated using microcrystalline cellulose as aid for combustion of polymers from waste of EEEs that usually contain flame retardants that impair the combustion. The composition and concentration of acid solutions (HNO{sub 3} or HNO{sub 3} plus HCl) were evaluated for metals and metalloids and NH{sub 4}OH solutions were investigated for Br absorption. Accuracy was evaluated by comparison of results with those obtained using high pressure microwave-assisted wet digestion (HP-MAWD) and also by the analysis of certified reference material (CRM) of polymer (EC680k—low-density polyethylene). Bromine determination was only feasible using digestion by MIC once losses were observed when HP-MAWD was used. Lower limits of detection were obtained for all analytes using MIC (from 0.005 μg g{sup −1} for Co by ICP-MS up to 3.120 μg g{sup −1} for Sb by ICP OES) in comparison to HP-MAWD due to the higher sample mass that can be digested (400 mg) and the use of diluted absorbing solutions. The combination of HNO{sub 3} and HCl for digestion showed to be crucial for quantitative recovery of some elements, as Cr and Sb

  9. Piezoelectric-based actuators for improved tractor-trailer performance (Conference Presentation)

    Science.gov (United States)

    Menicovich, David; Amitay, Michael; Gallardo, Daniele

    2017-04-01

    The application of piezo-electrically-driven synthetic-jet-based active flow control to reduce drag on tractor-trailers and to improve thermal mixing in refrigerated trailers was explored on full-scale tests. The active flow control technique that is being used relies on a modular system comprised of distributed, small, highly efficient actuators. These actuators, called synthetic jets, are jets that are synthesized at the edge of an orifice by a periodic motion of a piezoelectric diaphragm(s) mounted on one (or more) walls of a sealed cavity. The synthetic jet is zero net mass flux (ZNMF), but it allows momentum transfer to flow. It is typically driven near diaphragm and/or cavity resonance, and therefore, small electric input [O(10W)] is required. Another advantage of this actuator is that no plumbing is required. The system doesn't require changes to the body of the truck, can be easily reconfigured to various types of vehicles, and consumes small amounts of electrical power from the existing electrical system of the truck. The actuators are operated in a closed feedback loop based on inputs received from the tractor's electronic control unit, various system components and environmental sensors. The data are collected and processed on-board and transmitted to a cloud-based data management platform for further big data analytics and diagnostics. The system functions as a smart connected product through the interchange of data between the physical truck-mounted system and its cloud platform.

  10. Photoacoustic bio-quantification of graphene based nanomaterials at a single cell level (Conference Presentation)

    Science.gov (United States)

    Nedosekin, Dmitry A.; Nolan, Jacqueline; Biris, Alexandru S.; Zharov, Vladimir P.

    2017-03-01

    Arkansas Nanomedicine Center at the University of Arkansas for Medical Sciences in collaboration with other Arkansas Universities and the FDA-based National Center of Toxicological Research in Jefferson, AR is developing novel techniques for rapid quantification of graphene-based nanomaterials (GBNs) in various biological samples. All-carbon GBNs have wide range of potential applications in industry, agriculture, food processing and medicine; however, quantification of GBNs is difficult in carbon reach biological tissues. The accurate quantification of GBNs is essential for research on material toxicity and the development of GBNs-based drug delivery platforms. We have developed microscopy and cytometry platforms for detection and quantification of GBNs in single cells, tissue and blood samples using photoacoustic contrast of GBNs. We demonstrated PA quantification of individual graphene uptake by single cells. High-resolution PA microscopy provided mapping of GBN distribution within live cells to establish correlation with intracellular toxic phenomena using apoptotic and necrotic assays. This new methodology and corresponding technical platform provide the insight on possible toxicological risks of GBNs at singe cells levels. In addition, in vivo PA image flow cytometry demonstrated the capability to monitor of GBNs pharmacokinetics in mouse model and to map the resulting biodistribution of GBNs in mouse tissues. The integrated PA platform provided an unprecedented sensitivity toward GBNs and allowed to enhance conventional toxicology research by providing a direct correlation between uptake of GBNs at a single cell level and cell viability status.

  11. Lab-based ambient pressure X-ray photoelectron spectroscopy from past to present

    Science.gov (United States)

    Arble, Chris; Jia, Meng; Newberg, John T.

    2018-05-01

    Chemical interactions which occur at a heterogeneous interface between a gas and substrate are critical in many technological and natural processes. Ambient pressure X-ray photoelectron spectroscopy (AP-XPS) is a powerful spectroscopy tool that is inherently surface sensitive, elemental and chemical specific, with the ability to probe sample surfaces in the presence of a gas phase. In this review, we discuss the evolution of lab-based AP-XPS instruments, from the first development by Siegbahn and coworkers up through modern day systems. A comprehensive overview is given of heterogeneous experiments investigated to date via lab-based AP-XPS along with the different instrumental metrics that affect the quality of sample probing. We conclude with a discussion of future directions for lab-based AP-XPS, highlighting the efficacy for this in-demand instrument to continue to expand in its ability to significantly advance our understanding of surface chemical processes under in situ conditions in a technologically multidisciplinary setting.

  12. Nystagmus-based approach to vertebrobasilar stroke presenting as vertigo without initial neurologic signs.

    Science.gov (United States)

    Kim, Min-Beom; Boo, Sung Hyun; Ban, Jae Ho

    2013-01-01

    We aimed to investigate the clinical courses and common nystagmus of isolated vertigo patients with vertebrobasilar stroke. The patients who presented with isolated acute spontaneous vertigo with spontaneous nystagmus (acute vestibular syndrome) at the Emergency Department were retrospectively analyzed. They were referred to the Otolaryngology Department due to the absence of neurologic signs or even of imaging abnormalities after the initial examination at the Emergency Department. Various clinical features, including presenting symptoms, delayed neurologic signs, the site of infarction, and videonystagmographic (VNG) findings were analyzed. Of the 468 cases of acute vestibular syndrome, 23 (4.9%) cases of radiologically proven vertebrobasilar stroke were identified. Of the 23 patients, 17 (74%) showed aggravation of vertigo or delayed neurologic signs during the admission. In the analysis of VNG, 11 (48%) cases of direction-changing gaze-evoked nystagmus, 7 (30%) cases of fixation failure in the caloric test, 6 (27%) cases of periodic alternating nystagmus, and 4 (17%) cases of atypical head-shaking nystagmus were presented. Stroke occurred in the cerebellum (n=18, 78%), medulla (n=4, 17%), and pons (n=1, 4%). In the early stage of vertebrobasilar stroke, an accurate diagnosis was difficult in the Emergency Department even though a radiologic study was performed, but various VNG abnormalities and delayed neurologic signs could help to diagnose whether the origin is central or not. Copyright © 2013 S. Karger AG, Basel.

  13. Rediscovering Don Swanson: The Past, Present and Future of Literature-based Discovery

    Directory of Open Access Journals (Sweden)

    Neil R. Smalheiser

    2017-12-01

    Full Text Available Purpose: The late Don R. Swanson was well appreciated during his lifetime as Dean of the Graduate Library School at University of Chicago, as winner of the American Society for Information Science Award of Merit for 2000, and as author of many seminal articles. In this informal essay, I will give my personal perspective on Don’s contributions to science, and outline some current and future directions in literature-based discovery that are rooted in concepts that he developed. Design/methodology/approach: Personal recollections and literature review. Findings: The Swanson A-B-C model of literature-based discovery has been successfully used by laboratory investigators analyzing their findings and hypotheses. It continues to be a fertile area of research in a wide range of application areas including text mining, drug repurposing, studies of scientific innovation, knowledge discovery in databases, and bioinformatics. Recently, additional modes of discovery that do not follow the A-B-C model have also been proposed and explored (e.g. so-called storytelling, gaps, analogies, link prediction, negative consensus, outliers, and revival of neglected or discarded research questions. Research limitations: This paper reflects the opinions of the author and is not a comprehensive nor technically based review of literature-based discovery. Practical implications: The general scientific public is still not aware of the availability of tools for literature-based discovery. Our Arrowsmith project site maintains a suite of discovery tools that are free and open to the public (http://arrowsmith.psych.uic.edu, as does BITOLA which is maintained by Dmitar Hristovski (http:// http://ibmi.mf.uni-lj.si/bitola, and Epiphanet which is maintained by Trevor Cohen (http://epiphanet.uth.tmc.edu/. Bringing user-friendly tools to the public should be a high priority, since even more than advancing basic research in informatics, it is vital that we ensure that scientists

  14. Tracking Listeria monocytogenes contamination and virulence-associated characteristics in the ready-to-eat meat-based food products industry according to the hygiene level.

    Science.gov (United States)

    Henriques, A R; Gama, L T; Fraqueza, M J

    2017-02-02

    Listeria monocytogenes isolates collected from final products and food contact surfaces of 10 ready-to-eat meat-based food products (RTEMP) producing industries were analyzed to relate their virulence-associated characteristics and genetic profiles with the hygiene assessment of those industries. Together with sample collection, an audit was performed to evaluate the implemented food safety management system and to investigate the specific audit requisites more associated to the occurrence of those L. monocytogenes serogroups frequently related with human disease. L. monocytogenes was present in 18% of the samples. The isolates (n=62) were serogrouped and detection of virulence-associated genes inlA, inlB, inlC and inlJ, and also plcA, hlyA, actA and iap was done by multiplex PCR. After this initial characterization, selected isolates (n=31) were submitted to antibiotic resistance testing by the disk diffusion method for the currently most used human and veterinary antibiotics and resistance was low. These isolates were also subtyped by pulsed-field gel electrophoresis. Genotyping and serogrouping of L. monocytogenes isolates revealed a genetically diverse population. Our data indicate that contamination of final products does not seem to be uniquely related to the sampled food surfaces. The occurrence of those L. monocytogenes serogroups more commonly associated with human disease in industries with a high hygienic audit classification could be the result of a previous identification of the pathogen, with an enforcement of the hygiene program without recognizing the real source of contamination. This reinforces the importance of a conjoined diagnosis using audit data and microbiological testing. Food safety management systems of those industries need improvement, particularly in cleaning and sanitizing operations, analytical control, preventive maintenance, personal hygiene and root cause analysis. Copyright © 2016. Published by Elsevier B.V.

  15. A yeast co-culture-based biosensor for determination of waste water contamination levels.

    Science.gov (United States)

    Yudina, N Yu; Arlyapov, V A; Chepurnova, M A; Alferov, S V; Reshetilov, A N

    2015-10-01

    Artificial microbial co-cultures were formed to develop the receptor element of a biosensor for assessment of biological oxygen demand (BOD). The co-cultures possessed broad substrate specificities and enabled assays of water and fermentation products within a broad BOD range (2.4-80 mg/dm(3)) with a high correlation to the standard method (R = 0.9988). The use of the co-cultures of the yeasts Pichia angusta, Arxula adeninivorans and Debaryomyces hansenii immobilized in N-vinylpyrrolidone-modified poly(vinyl alcohol) enabled developing a BOD biosensor possessing the characteristics not inferior to those in the known biosensors. The results are indicative of a potential of using these co-cultures as the receptor element base in prototype models of instruments for broad application. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. GaSb-based single-mode distributed feedback lasers for sensing (Conference Presentation)

    Science.gov (United States)

    Gupta, James A.; Bezinger, Andrew; Lapointe, Jean; Poitras, Daniel; Aers, Geof C.

    2017-02-01

    GaSb-based tunable single-mode diode lasers can enable rapid, highly-selective and highly-sensitive absorption spectroscopy systems for gas sensing. In this work, single-mode distributed feedback (DFB) laser diodes were developed for the detection of various trace gases in the 2-3.3um range, including CO2, CO, HF, H2S, H2O and CH4. The lasers were fabricated using an index-coupled grating process without epitaxial regrowth, making the process significantly less expensive than conventional DFB fabrication. The devices are based on InGaAsSb/AlGaAsSb separate confinement heterostructures grown on GaSb by molecular beam epitaxy. DFB lasers were produced using a two step etch process. Narrow ridge waveguides were first defined by optical lithography and etched into the semiconductor. Lateral gratings were then defined on both sides of the ridge using electron-beam lithography and etched to produce the index-grating. Effective index modeling was used to optimize the ridge width, etch depths and the grating pitch to ensure single-lateral-mode operation and adequate coupling strength. The effective index method was further used to simulate the DFB laser emission spectrum, based on a transfer matrix model for light transmission through the periodic structure. The fabricated lasers exhibit single-mode operation which is tunable through the absorption features of the various target gases by adjustment of the drive current. In addition to the established open-path sensing applications, these devices have great potential for optoelectronic integrated gas sensors, making use of integrated photodetectors and possibly on-chip Si photonics waveguide structures.

  17. Evaluation of a new carbon/zirconia-based sorbent for the cleanup of food extracts in multiclass analysis of pesticides and environmental contaminants

    Science.gov (United States)

    A novel carbon/zirconia based material, SupelTM QuE Verde (Verde), was evaluated in a filter-vial dispersive solid phase extraction (d-SPE) cleanup of QuEChERS extracts of pork, salmon, kale, and avocado for residual analysis of pesticides and environmental contaminants. Low pressure (LP) GC-MS/MS w...

  18. Past, Present and Future Aspects of Laser-Based Synchronization at FLASH

    OpenAIRE

    Schulz, Sebastian; Bousonville, Michael; Steffen, Bernd; Sydlo, Cezary; Zummack, Falco; Kozak, Tomasz; Predki, Pawel; Kuhl, Alexander; Czwalinna, Marie Kristin; Felber, Matthias; Heuer, Michael; Lamb, Thorsten; Mueller, Jost; Peier, Peter; Ruzin, Sergej

    2013-01-01

    Free-electron lasers, like FLASH and the upcoming European XFEL, are capable of producing XUV and X-ray pulses of a few femtoseconds duration. For time-resolved pump-probe experiments and the externally seeded operation mode it is crucial not only to stabilize the arrival time of the electron bunches, but also to achieve a synchronization accuracy of external lasers on the same timescale. This can only be realized with a laser-based synchronization infrastructure. At FLASH, a periodic femtose...

  19. [Present status and trend of heart fluid mechanics research based on medical image analysis].

    Science.gov (United States)

    Gan, Jianhong; Yin, Lixue; Xie, Shenghua; Li, Wenhua; Lu, Jing; Luo, Anguo

    2014-06-01

    With introduction of current main methods for heart fluid mechanics researches, we studied the characteristics and weakness for three primary analysis methods based on magnetic resonance imaging, color Doppler ultrasound and grayscale ultrasound image, respectively. It is pointed out that particle image velocity (PIV), speckle tracking and block match have the same nature, and three algorithms all adopt block correlation. The further analysis shows that, with the development of information technology and sensor, the research for cardiac function and fluid mechanics will focus on energy transfer process of heart fluid, characteristics of Chamber wall related to blood fluid and Fluid-structure interaction in the future heart fluid mechanics fields.

  20. A versatile computer based system for data acquisition manipulation and presentation

    International Nuclear Information System (INIS)

    Bardsley, D.J.

    1985-12-01

    A data acquisition system based on the Microdata M 1600L data logger and a Digital Equipment Corporation (DEC) VT103 computer system has been set up for use in a wide range of research and development projects in the field of fission detectors and associated technology. The philosophy underlying the system and its important features are described. Operating instructions for the logger are given, and its application to experimental measurements is considered. Observations on whole system performance, and recommendations for improvements are made. (U.K.)

  1. Contaminant resorption during soil washing

    International Nuclear Information System (INIS)

    Gombert, D.

    1993-01-01

    To evaluate the applicability of soil washing to a specific site requires some basic research in how contaminants are bound. Much can be learned from sequential extraction methodology based on micronutrient bioavailability studies wherein the soil matrix is chemically dissected to selectively remove particular fixation mechanisms independently. This procedure uses a series of progressively more aggressive solvents to dissolve the principle phases that make up a soil, however, the published studies do not appear to consider the potential for a contaminant released from one type of site to resorb on another site during an extraction. This physical model assumes no ion exchange or adsorption at sites either previously occupied by other ions, or exposed by the dissolution. Therefore, to make engineering use of the sequential extraction data, the release of contamination must be evaluated relative to the effects of resorption. Time release studies were conducted to determine the optimum duration for extraction to maximize complete destruction of the target matrix fraction while minimizing contaminant resorption. Tests with and without a potassium brine present to inhibit cesium resorption indicated extraction efficiency could be enhanced by as much as a factor of ten using the brine

  2. Heterotopic salivary gland presenting as a discharging sinus in the base of the neck

    Directory of Open Access Journals (Sweden)

    Shraddha Jain

    2011-12-01

    Full Text Available We report a case of congenital heterotopic salivary gland with draining sinus in the lower neck on the right side of a 10-year-old female, which we initially thought to be a branchial fistula. Heterotopic salivary glands are rare lesions in the neck and when present appear very similar to branchial cleft sinus or fistula. This congenital lesion is rare. This is probably the first report from India. It is important to report this case to raise the awareness of this condition.

  3. Social class conflict presented in “the kite runner” novel based on marxism theory

    OpenAIRE

    Yohanes Eko Rubiyanto

    2017-01-01

    Abstract The writer conducts the research related to class conflict which is presented in Khaled Hosseini’s “The Kite Runner” novel. This qualitative research is written to analyze the conflicts that happen in Afghan society which is mainly caused by difference of social class. The research is conducted by using library research. The method used in this research is descriptive qualitative method as the data are described in the form of sentences. The steps of collecting the data in this re...

  4. Avatar Weight Estimates based on Footstep Sounds in Three Presentation Formats

    DEFF Research Database (Denmark)

    Sikström, Erik; Götzen, Amalia De; Serafin, Stefania

    2015-01-01

    When evaluating a sound design for virtual environment, the context where it is to be implemented in may have an influence on how it may be perceived. In this paper we perform an experiment comparing three presentation formats (audio only, video with audio and an interactive immersive VR format......) and their influences on a sound design evaluation task concerning footstep sounds. The evaluation involved estimating the perceived weight of a virtual avatar seen from a first person perspective, as well as the suitability of the sound effect relative to the context. The results show significant differences for three...

  5. [The P300-based brain-computer interface: presentation of the complex "flash + movement" stimuli].

    Science.gov (United States)

    Ganin, I P; Kaplan, A Ia

    2014-01-01

    The P300 based brain-computer interface requires the detection of P300 wave of brain event-related potentials. Most of its users learn the BCI control in several minutes and after the short classifier training they can type a text on the computer screen or assemble an image of separate fragments in simple BCI-based video games. Nevertheless, insufficient attractiveness for users and conservative stimuli organization in this BCI may restrict its integration into real information processes control. At the same time initial movement of object (motion-onset stimuli) may be an independent factor that induces P300 wave. In current work we checked the hypothesis that complex "flash + movement" stimuli together with drastic and compact stimuli organization on the computer screen may be much more attractive for user while operating in P300 BCI. In 20 subjects research we showed the effectiveness of our interface. Both accuracy and P300 amplitude were higher for flashing stimuli and complex "flash + movement" stimuli compared to motion-onset stimuli. N200 amplitude was maximal for flashing stimuli, while for "flash + movement" stimuli and motion-onset stimuli it was only a half of it. Similar BCI with complex stimuli may be embedded into compact control systems requiring high level of user attention under impact of negative external effects obstructing the BCI control.

  6. Low-cost, smartphone based frequency doubling technology visual field testing using virtual reality (Conference Presentation)

    Science.gov (United States)

    Alawa, Karam A.; Sayed, Mohamed; Arboleda, Alejandro; Durkee, Heather A.; Aguilar, Mariela C.; Lee, Richard K.

    2017-02-01

    Glaucoma is the leading cause of irreversible blindness worldwide. Due to its wide prevalence, effective screening tools are necessary. The purpose of this project is to design and evaluate a system that enables portable, cost effective, smartphone based visual field screening based on frequency doubling technology. The system is comprised of an Android smartphone to display frequency doubling stimuli and handle processing, a Bluetooth remote for user input, and a virtual reality headset to simulate the exam. The LG Nexus 5 smartphone and BoboVR Z3 virtual reality headset were used for their screen size and lens configuration, respectively. The system is capable of running the C-20, N-30, 24-2, and 30-2 testing patterns. Unlike the existing system, the smartphone FDT tests both eyes concurrently by showing the same background to both eyes but only displaying the stimulus to one eye at a time. Both the Humphrey Zeiss FDT and the smartphone FDT were tested on five subjects without a history of ocular disease with the C-20 testing pattern. The smartphone FDT successfully produced frequency doubling stimuli at the correct spatial and temporal frequency. Subjects could not tell which eye was being tested. All five subjects preferred the smartphone FDT to the Humphrey Zeiss FDT due to comfort and ease of use. The smartphone FDT is a low-cost, portable visual field screening device that can be used as a screening tool for glaucoma.

  7. Advances in OLED/OPD-based sensors and spectrometer-on-a-chip (Conference Presentation)

    Science.gov (United States)

    Shinar, Joseph; Kaudal, Rajiv; Manna, Eeshita; Fungura, Fadzai; Shinar, Ruth

    2016-09-01

    We describe ongoing advances toward achieving all-organic optical sensors and a spectrometer on a chip. Two-dimensional combinatorial arrays of microcavity OLEDs (μcOLEDs) with systematically varying optical cavity lengths are fabricated on a single chip by changing the thickness of different organic and/or spacer layers sandwiched between two metal electrodes (one very thin) that form the cavity. The broad spectral range is achieved by utilizing materials that result in white OLEDs (WOLEDs) when fabricated on a standard ITO substrate. The tunable and narrower emissions from the μcOLEDs serve as excitation sources in luminescent sensors and in monitoring light absorption. For each wavelength, the light from the μcOLED is partially absorbed by a sample under study and the light emitted by an electronically excited sample, or the transmitted light is detected by a photodetector (PD). To obtain a compact monitor, an organic PD (OPD) or a perovskite-based PD is integrated with the μcOLED array. We show the potential of encompassing a broader wavelength range by using WOLED materials to fabricate the μcOLEDs. The utility of the all-organic analytical devices is demonstrated by monitoring oxygen, and bioanalytes based on oxygen detection, as well as the absorption spectra of dyes.

  8. Retrospective analysis of heavy metal contamination in Rhode Island based on old and new herbarium specimens.

    Science.gov (United States)

    Rudin, Sofia M; Murray, David W; Whitfeld, Timothy J S

    2017-01-01

    Herbarium specimens may provide a record of past environmental conditions, including heavy metal pollution. To explore this potential, we compared concentrations of copper, lead, and zinc in historical and new collections from four sites in Rhode Island, USA. We compared historical specimens (1846 to 1916) to congener specimens collected in 2015 at three former industrial sites in Providence, Rhode Island, and one nonindustrial site on Block Island. Leaf material was prepared by UltraWAVE SRC Microwave Digestion, and heavy metal concentrations were measured by inductively coupled plasma-atomic emission spectroscopy. Heavy metal concentrations in the historical and new specimens were measurable for all elements tested, and levels of copper and zinc were comparable in the historical and 2015 collections. By contrast, the concentration of lead declined at all sites over time. Significant variability in heavy metal concentration was observed between taxa, reflecting their varied potential for elemental accumulation. It seems clear that herbarium specimens can be used to evaluate past levels of pollution and assess local environmental changes. With careful sampling effort, these specimens can be a valuable part of environmental science research. Broadening the possible applications for herbarium collections in this way increases their relevance in an era of reduced funding for collections-based research.

  9. Late-presenting developmental dysplasia of the hip in Jordanian males. A retrospective hospital based study

    Directory of Open Access Journals (Sweden)

    Omar Q. Samarah

    2016-02-01

    Full Text Available Objectives: To describe the pattern of developmental dysplasia of the hip (DDH in late presenting Jordanian male patients and identify the risk factors and associated findings. Methods: This is a retrospective study of 1145 male patients who attended the Pediatric Orthopedic Clinic for a DDH check up. This study was carried out in the Orthopedic Section, Special Surgery Department, Faculty of Medicine, The University of Jordan, Amman, Jordan between March 2011 and October 2014. Data was collected from medical records, and x-ray measurements were evaluated. Results: Of the 1145 male patients, 43 (3.75% with 70 involved hips were diagnosed with late- presenting DDH. Being a first-born baby resulted in 41.9% increased risk for DDH. Cesarian delivery was significantly associated with an increased risk of hip dislocation (p=0.004 while normal delivery was significantly associated with acetabular dysplasia (p=0.004. No predictable risk factors were found in 44.2% patients with DDH. Bilateral cases were more common than unilateral cases: (26 [60.5%] versus 17 [39.5%]. Limited abduction was a constant finding in all dislocated hips (p less than 0.001. Associated conditions, such as club foot and congenital muscular torticollis were not observed. Conclusion: Cesarian section is a significant risk for dislocated hips while normal delivery is significantly associated with acetabular dysplasia. Bilateral DDH is more common than the unilateral. Club foot and torticollis were not observed in this series.

  10. A Methodology for Equitable Performance Assessment and Presentation of Wave Energy Converters Based on Sea Trials

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Pecher, Arthur; Margheritini, Lucia

    2013-01-01

    This paper provides a methodology for the analysis and presentation of data obtained from sea trials of wave energy converters (WEC). The equitable aspect of this methodology lies in its wide application, as any WEC at any scale or stage of development can be considered as long as the tests are p...... parameters influence the performance of the WEC can also be investigated using this methodology.......This paper provides a methodology for the analysis and presentation of data obtained from sea trials of wave energy converters (WEC). The equitable aspect of this methodology lies in its wide application, as any WEC at any scale or stage of development can be considered as long as the tests...... leads to testing campaigns that are not as extensive as desired. Therefore, the performance analysis should be robust enough to allow for not fully complete sea trials and sub optimal performance data. In other words, this methodology is focused at retrieving the maximum amount of useful information out...

  11. Water Contamination

    Science.gov (United States)

    ... Statistics Training & Education Policy & Recommendations Fast Facts Healthy Water Sites Healthy Water Drinking Water Healthy Swimming Global ... type=”submit” value=”Submit” /> Healthy Water Home Water Contamination Recommend on Facebook Tweet Share Compartir On ...

  12. Risk mapping of NO/sub 3/-N contamination on groundwater under intensive rice-based cropping systems in the Philippines

    International Nuclear Information System (INIS)

    Pascual, C.M.; Baga, M.C.S.; Valencia, D.P.

    2005-01-01

    The groundwater resources in a 265 ha watershed of highly diversified and intensive rice-based environment was endangered to NO/sub 3/-N contamination with spatial degree of influence and temporal vulnerability risks as affected by intensive cropping systems with application of high N-fertilizer and judicious use of groundwater for irrigation. Such nitrate contamination levels are above the World Health Organization's maximum contamination level of 10 ppm for drinking water. Tree-joining, complete cluster analysis of monthly groundwater depths on observation wells revealed three distinct groups of wells differentiated by groundwater depths. Planting of nitrate catch crops such as legumes to reduce groundwater contamination and vigorous information dissemination on ill-effects of high NO/sub 3/-N, as well as groundwater recharging were considered to reduce contamination. However, the groundwater extraction for irrigation is still sustainable due to natural recharging of rainfall and hydraulic connections from surface water along rivers and creeks. The combined-use of GIS and GPS proved useful for spatial and temporal risk mapping assessment on groundwater NO/sub 3/-N vulnerability among other geo-referenced attributes of groundwater and other environmental considerations at the study site. Such systems analysis tools can be used by planners, researchers, extension workers, students and farmers for other sustainable development and environmental risk mapping, assessment, extrapolation analysis and strategic planning of sustainable development of the environment. (author)

  13. Fetal Cell Based Prenatal Diagnosis: Perspectives on the Present and Future

    Directory of Open Access Journals (Sweden)

    Morris Fiddler

    2014-09-01

    Full Text Available The ability to capture and analyze fetal cells from maternal circulation or other sources during pregnancy has been a goal of prenatal diagnostics for over thirty years. The vision of replacing invasive prenatal diagnostic procedures with the prospect of having the entire fetal genome in hand non-invasively for chromosomal and molecular studies for both clinical and research use has brought many investigators and innovations into the effort. While the object of this desire, however, has remained elusive, the aspiration for this approach to non-invasive prenatal diagnosis remains and the inquiry has continued. With the advent of screening by cell-free DNA analysis, the standards for fetal cell based prenatal diagnostics have been sharpened. Relevant aspects of the history and the current status of investigations to meet the goal of having an accessible and reliable strategy for capturing and analyzing fetal cells during pregnancy are reviewed.

  14. Activity-Based Intelligence prevedere il futuro osservando il presente con gli strumenti Hexagon Geospatial

    Directory of Open Access Journals (Sweden)

    Massimo Zotti

    2015-06-01

    Full Text Available The intelligence of human activities on the earth's surface, obtained through the analysis of earth observation data and other geospatial information, is vital for the planning and execution of any military action, for peacekeeping or for humanitarian emergencies. The success of these actions largely depends on the ability to analyze timely data from multiple sources. However, the proliferation of new sources of intelligence in a Geospatial big data scenario increasingly complicate the analysis of such activities by human analysts. Modern technologies solve these problems by enabling the Activity Based Intelligence, a methodology that improves the efficiency and timeliness of intelligence through the analysis of historical, current and future activity, to identify patterns, trends and relationships hidden in large data collections from different sources.

  15. Bilinear common spatial pattern for single-trial ERP-based rapid serial visual presentation triage

    Science.gov (United States)

    Yu, K.; Shen, K.; Shao, S.; Ng, W. C.; Li, X.

    2012-08-01

    Common spatial pattern (CSP) analysis is a useful tool for the feature extraction of event-related potentials (ERP). However, CSP is essentially time invariant, and thus unable to exploit the temporal information of ERP. This paper proposes a variant of CSP, namely bilinear common spatial pattern (BCSP), which is capable of accommodating both spatial and temporal information. BCSP generalizes CSP through iteratively optimizing bilinear filters. These bilinear filters constitute a spatio-temporal subspace in which the separation between two conditions is maximized. The method is unique in the sense that it is mathematically intuitive and simple, as all the bilinear filters are obtained by maximizing the power ratio as CSP does. The proposed method was evaluated on 20 subjects’ ERP data collected in rapid serial visual presentation triage experiments. The results show that BCSP achieved significantly higher average test accuracy (12.3% higher, p < 0.001).

  16. Social class conflict presented in “the kite runner” novel based on marxism theory

    Directory of Open Access Journals (Sweden)

    Yohanes Eko Rubiyanto

    2017-04-01

    The writer conducts the research related to class conflict which is presented in Khaled Hosseini’s “The Kite Runner” novel. This qualitative research is written to analyze the conflicts that happen in Afghan society which is mainly caused by difference of social class. The research is conducted by using library research. The method used in this research is descriptive qualitative method as the data are described in the form of sentences. The steps of collecting the data in this research are reading both the novel and the supporting theories related, analyzing, organizing and displaying the data to allow conclusions to be drawn. The results show that the society in the twentieth is fundamentally separated by two large groups namely Pashtun and Hazara. They are inhabit Afghanistan as told in The Kite Runner. The Pashtuns act as the dominant upper class and the Hazaras fill the society of the lower class which fits the theory of Marxism.

  17. Origami-based mechanical metamaterials with tunable frequency band structures (Conference Presentation)

    Science.gov (United States)

    Yasuda, Hiromi; Pratt, Riley; Yang, Jinkyu

    2017-04-01

    We investigate wave dynamics in origami-based mechanical metamaterials composed of bellows-like origami structures, specifically the Tachi-Miura Polyhedron (TMP). One of the unique features of the TMP is that its structural deformations take place only along the crease lines, therefore the structure can be made of rigid plates and hinges. By utilizing this feature, we introduce linear torsional springs to model the crease lines and derive the force and displacement relationship of the TMP structure along the longitudinal direction. Our analysis shows strain softening/hardening behaviors in compression/tensile regions respectively, and the force-displacement curve can be manipulated by altering the initial configuration of the TMP (e.g., the initial folding angle). We also fabricate physical prototypes and measure the force-displacement behavior to verify our analytical model. Based on this static analysis on the TMP, we simplify the TMP structure into a linkage model, preserving the tunable strain softening/hardening behaviors. Dynamic analysis is also conducted numerically to analyze the frequency response of the simplified TMP unit cell under harmonic excitations. The simplified TMP exhibits a transition between linear and nonlinear behaviors, which depends on the amplitude of the excitation and the initial configuration. In addition, we design a 1D system composed of simplified TMP unit cells and analyze the relationship between frequency and wave number. If two different configurations of the unit cell (e.g., different initial folding angles) are connected in an alternating arrangement, the system develops frequency bandgaps. These unique static/dynamic behaviors can be exploited to design engineering devices which can handle vibrations and impact in an efficient manner.

  18. Addressing and Presenting Quality of Satellite Data via Web-Based Services

    Science.gov (United States)

    Leptoukh, Gregory; Lynnes, C.; Ahmad, S.; Fox, P.; Zednik, S.; West, P.

    2011-01-01

    With the recent attention to climate change and proliferation of remote-sensing data utilization, climate model and various environmental monitoring and protection applications have begun to increasingly rely on satellite measurements. Research application users seek good quality satellite data, with uncertainties and biases provided for each data point. However, different communities address remote sensing quality issues rather inconsistently and differently. We describe our attempt to systematically characterize, capture, and provision quality and uncertainty information as it applies to the NASA MODIS Aerosol Optical Depth data product. In particular, we note the semantic differences in quality/bias/uncertainty at the pixel, granule, product, and record levels. We outline various factors contributing to uncertainty or error budget; errors. Web-based science analysis and processing tools allow users to access, analyze, and generate visualizations of data while alleviating users from having directly managing complex data processing operations. These tools provide value by streamlining the data analysis process, but usually shield users from details of the data processing steps, algorithm assumptions, caveats, etc. Correct interpretation of the final analysis requires user understanding of how data has been generated and processed and what potential biases, anomalies, or errors may have been introduced. By providing services that leverage data lineage provenance and domain-expertise, expert systems can be built to aid the user in understanding data sources, processing, and the suitability for use of products generated by the tools. We describe our experiences developing a semantic, provenance-aware, expert-knowledge advisory system applied to NASA Giovanni web-based Earth science data analysis tool as part of the ESTO AIST-funded Multi-sensor Data Synergy Advisor project.

  19. Fiber-based optic sensor for detecting human blood clot: present and future revival

    Science.gov (United States)

    Elshikeri, Nada; Bakhtiar, Hazri

    2018-05-01

    Sustaining human’s life-frame away from being impeded by the clot - ghost term, we attempt to approach a mobile fiber-based optical sensor (f-s) for detecting blood clot in a blood vessel (intra-arteries/veins). Blood vessels are the part of the circulatory system that transport blood throughout the human body, thus their significance of being protected arise to the monograph focus. MRI (magnetic resonance imaging), X-rays and other medical instruments are diagnostic immobility techniques with a slackest interval. The corer causation of fiber-based optical sensor is to detect a clump of blood in the bloodstream by providing a prompt mobile diagnostic intervals preserving last-minutes-breath of human’s life. The detector (f-s) has been etched by diluting sulphuric acid ~10% at certain zone to sensate its function. The in-vitro monograph peaks its maximal monitoring when the sensor is attached to Raman Spectroscopy (RS) setup. RS quantifies the relative intensities of fibrinogen bond, which is the first type of blood coagulation elements of blood plasma. Blood coagulation parameters are the major concern of the monograph investigation, such as total haemoglobin (tHb), clotting reaction time (t), clot progression time (t2), maximum clot amplitude (ma) and mean refractive index (r). A blood sample will be drawn from the patient and after centrifugation to separate blood plasma from its constituents, then an immediate sloshing of blood plasma in the (f-s) packet which has its plug-in to RS. Estimating the quantitative analysis of blood sample concentration, RS will determine the presence of coagulation in terms of intensity and medical procedures will dominate the treatment process. Thus, the suggestive monograph provides a definite instrument for investigating blood coagulation intra-arteries/veins promptly.

  20. Purifying arsenic and fluoride-contaminated water by a novel graphene-based nanocomposite membrane of enhanced selectivity and sustained flux.

    Science.gov (United States)

    Pal, Madhubonti; Mondal, Mrinal Kanti; Paine, Tapan Kanti; Pal, Parimal

    2018-06-01

    A novel graphene-based nanocomposite membrane was synthesized by interfacial polymerization (IP) through chemical bonding of the graphene oxide (GO) layer to polyethersulfone surface. Detailed characterization of the composite membrane through AFM, SEM, ATR-FTIR, XRD analysis, and Raman spectroscopy indicates strong potential of the membrane in highly selective removal of the toxic contaminants like arsenic and fluoride while permeating the essential minerals like calcium and magnesium. This makes the membrane suitable for production of safe drinking water from contaminated water. The membrane applied in a flat-sheet cross-flow module succeeded in removal of more than 98% arsenic and around 80% fluoride from contaminated water while selectively retaining the useful calcium and magnesium minerals in drinking water. A sustained pure water flux of around 150 LMH (liter per square meter per hour) during operation over long hours (> 150 h) with only 3-5% drop in flux indicates antifouling character of the membrane module.

  1. Integrated computer-aided forensic case analysis, presentation, and documentation based on multimodal 3D data.

    Science.gov (United States)

    Bornik, Alexander; Urschler, Martin; Schmalstieg, Dieter; Bischof, Horst; Krauskopf, Astrid; Schwark, Thorsten; Scheurer, Eva; Yen, Kathrin

    2018-06-01

    Three-dimensional (3D) crime scene documentation using 3D scanners and medical imaging modalities like computed tomography (CT) and magnetic resonance imaging (MRI) are increasingly applied in forensic casework. Together with digital photography, these modalities enable comprehensive and non-invasive recording of forensically relevant information regarding injuries/pathologies inside the body and on its surface. Furthermore, it is possible to capture traces and items at crime scenes. Such digitally secured evidence has the potential to similarly increase case understanding by forensic experts and non-experts in court. Unlike photographs and 3D surface models, images from CT and MRI are not self-explanatory. Their interpretation and understanding requires radiological knowledge. Findings in tomography data must not only be revealed, but should also be jointly studied with all the 2D and 3D data available in order to clarify spatial interrelations and to optimally exploit the data at hand. This is technically challenging due to the heterogeneous data representations including volumetric data, polygonal 3D models, and images. This paper presents a novel computer-aided forensic toolbox providing tools to support the analysis, documentation, annotation, and illustration of forensic cases using heterogeneous digital data. Conjoint visualization of data from different modalities in their native form and efficient tools to visually extract and emphasize findings help experts to reveal unrecognized correlations and thereby enhance their case understanding. Moreover, the 3D case illustrations created for case analysis represent an efficient means to convey the insights gained from case analysis to forensic non-experts involved in court proceedings like jurists and laymen. The capability of the presented approach in the context of case analysis, its potential to speed up legal procedures and to ultimately enhance legal certainty is demonstrated by introducing a number of

  2. Using Model-Based System Engineering to Provide Artifacts for NASA Project Life-Cycle and Technical Reviews Presentation

    Science.gov (United States)

    Parrott, Edith L.; Weiland, Karen J.

    2017-01-01

    This is the presentation for the AIAA Space conference in September 2017. It highlights key information from Using Model-Based Systems Engineering to Provide Artifacts for NASA Project Life-cycle and Technical Reviews paper.

  3. Evaluation of targeted and untargeted effects-based monitoring tools to assess impacts of contaminants of emerging concern on fish in the South Platte River, CO.

    Science.gov (United States)

    Ekman, Drew R; Keteles, Kristen; Beihoffer, Jon; Cavallin, Jenna E; Dahlin, Kenneth; Davis, John M; Jastrow, Aaron; Lazorchak, James M; Mills, Marc A; Murphy, Mark; Nguyen, David; Vajda, Alan M; Villeneuve, Daniel L; Winkelman, Dana L; Collette, Timothy W

    2018-08-01

    Rivers in the arid Western United States face increasing influences from anthropogenic contaminants due to population growth, urbanization, and drought. To better understand and more effectively track the impacts of these contaminants, biologically-based monitoring tools are increasingly being used to complement routine chemical monitoring. This study was initiated to assess the ability of both targeted and untargeted biologically-based monitoring tools to discriminate impacts of two adjacent wastewater treatment plants (WWTPs) on Colorado's South Platte River. A cell-based estrogen assay (in vitro, targeted) determined that water samples collected downstream of the larger of the two WWTPs displayed considerable estrogenic activity in its two separate effluent streams. Hepatic vitellogenin mRNA expression (in vivo, targeted) and NMR-based metabolomic analyses (in vivo, untargeted) from caged male fathead minnows also suggested estrogenic activity downstream of the larger WWTP, but detected significant differences in responses from its two effluent streams. The metabolomic results suggested that these differences were associated with oxidative stress levels. Finally, partial least squares regression was used to explore linkages between the metabolomics responses and the chemical contaminants that were detected at the sites. This analysis, along with univariate statistical approaches, identified significant covariance between the biological endpoints and estrone concentrations, suggesting the importance of this contaminant and recommending increased focus on its presence in the environment. These results underscore the benefits of a combined targeted and untargeted biologically-based monitoring strategy when used alongside contaminant monitoring to more effectively assess ecological impacts of exposures to complex mixtures in surface waters. Published by Elsevier Ltd.

  4. Photovoltaic reciprocity and quasi-Fermi level splitting in nanostructure-based solar cells (Conference Presentation)

    Science.gov (United States)

    Aeberhard, Urs

    2017-04-01

    The photovoltaic reciprocity theory relates the electroluminescence spectrum of a solar cell under applied bias to the external photovoltaic quantum efficiency of the device as measured at short circuit conditions [1]. So far, the theory has been verified for a wide range of devices and material systems and forms the basis of a growing number of luminesecence imaging techniques used in the characterization of photovoltaic materials, cells and modules [2-5]. However, there are also some examples where the theory fails, such as in the case of amorphous silicon. In our contribution, we critically assess the assumptions made in the derivation of the theory and compare its predictions with rigorous formal relations as well as numerical computations in the framework of a comprehensive quantum-kinetic theory of photovoltaics [6] as applied to ultra-thin absorber architectures [7]. One of the main applications of the photovoltaic reciprocity relation is the determination of quasi-Fermi level splittings (QFLS) in solar cells from the measurement of luminescence. In nanostructure-based photovoltaic architectures, the determination of QFLS is challenging, but instrumental to assess the performance potential of the concepts. Here, we use our quasi-Fermi level-free theory to investigate existence and size of QFLS in quantum well and quantum dot solar cells. [1] Uwe Rau. Reciprocity relation between photovoltaic quantum efficiency and electrolumines- cent emission of solar cells. Phys. Rev. B, 76(8):085303, 2007. [2] Thomas Kirchartz and Uwe Rau. Electroluminescence analysis of high efficiency cu(in,ga)se2 solar cells. J. Appl. Phys., 102(10), 2007. [3] Thomas Kirchartz, Uwe Rau, Martin Hermle, Andreas W. Bett, Anke Helbig, and Jrgen H. Werner. Internal voltages in GaInP-GaInAs-Ge multijunction solar cells determined by electro- luminescence measurements. Appl. Phys. Lett., 92(12), 2008. [4] Thomas Kirchartz, Anke Helbig, Wilfried Reetz, Michael Reuter, Jürgen H. Werner, and

  5. Prostate cancer mortality reduction by prostate-specific antigen-based screening adjusted for nonattendance and contamination in the European Randomised Study of Screening for Prostate Cancer (ERSPC).

    Science.gov (United States)

    Roobol, Monique J; Kerkhof, Melissa; Schröder, Fritz H; Cuzick, Jack; Sasieni, Peter; Hakama, Matti; Stenman, Ulf Hakan; Ciatto, Stefano; Nelen, Vera; Kwiatkowski, Maciej; Lujan, Marcos; Lilja, Hans; Zappa, Marco; Denis, Louis; Recker, Franz; Berenguer, Antonio; Ruutu, Mirja; Kujala, Paula; Bangma, Chris H; Aus, Gunnar; Tammela, Teuvo L J; Villers, Arnauld; Rebillard, Xavier; Moss, Sue M; de Koning, Harry J; Hugosson, Jonas; Auvinen, Anssi

    2009-10-01

    Prostate-specific antigen (PSA) based screening for prostate cancer (PCa) has been shown to reduce prostate specific mortality by 20% in an intention to screen (ITS) analysis in a randomised trial (European Randomised Study of Screening for Prostate Cancer [ERSPC]). This effect may be diluted by nonattendance in men randomised to the screening arm and contamination in men randomised to the control arm. To assess the magnitude of the PCa-specific mortality reduction after adjustment for nonattendance and contamination. We analysed the occurrence of PCa deaths during an average follow-up of 9 yr in 162,243 men 55-69 yr of age randomised in seven participating centres of the ERSPC. Centres were also grouped according to the type of randomisation (ie, before or after informed written consent). Nonattendance was defined as nonattending the initial screening round in ERSPC. The estimate of contamination was based on PSA use in controls in ERSPC Rotterdam. Relative risks (RRs) with 95% confidence intervals (CIs) were compared between an ITS analysis and analyses adjusting for nonattendance and contamination using a statistical method developed for this purpose. In the ITS analysis, the RR of PCa death in men allocated to the intervention arm relative to the control arm was 0.80 (95% CI, 0.68-0.96). Adjustment for nonattendance resulted in a RR of 0.73 (95% CI, 0.58-0.93), and additional adjustment for contamination using two different estimates led to estimated reductions of 0.69 (95% CI, 0.51-0.92) to 0.71 (95% CI, 0.55-0.93), respectively. Contamination data were obtained through extrapolation of single-centre data. No heterogeneity was found between the groups of centres. PSA screening reduces the risk of dying of PCa by up to 31% in men actually screened. This benefit should be weighed against a degree of overdiagnosis and overtreatment inherent in PCa screening.

  6. Detection of Endotoxin Contamination of Graphene Based Materials Using the TNF-α Expression Test and Guidelines for Endotoxin-Free Graphene Oxide Production.

    Directory of Open Access Journals (Sweden)

    Sourav P Mukherjee

    Full Text Available Nanomaterials may be contaminated with bacterial endotoxin during production and handling, which may confound toxicological testing of these materials, not least when assessing for immunotoxicity. In the present study, we evaluated the conventional Limulus amebocyte lysate (LAL assay for endotoxin detection in graphene based material (GBM samples, including graphene oxide (GO and few-layered graphene (FLG. Our results showed that some GO samples interfered with various formats of the LAL assay. To overcome this problem, we developed a TNF-α expression test (TET using primary human monocyte-derived macrophages incubated in the presence or absence of the endotoxin inhibitor, polymyxin B sulfate, and found that this assay, performed with non-cytotoxic doses of the GBM samples, enabled unequivocal detection of endotoxin with a sensitivity that is comparable to the LAL assay. FLG also triggered TNF-α production in the presence of the LPS inhibitor, pointing to an intrinsic pro-inflammatory effect. Finally, we present guidelines for the preparation of endotoxin-free GO, validated by using the TET.

  7. Quantitative analysis of retina layer elasticity based on automatic 3D segmentation (Conference Presentation)

    Science.gov (United States)

    He, Youmin; Qu, Yueqiao; Zhang, Yi; Ma, Teng; Zhu, Jiang; Miao, Yusi; Humayun, Mark; Zhou, Qifa; Chen, Zhongping

    2017-02-01

    Age-related macular degeneration (AMD) is an eye condition that is considered to be one of the leading causes of blindness among people over 50. Recent studies suggest that the mechanical properties in retina layers are affected during the early onset of disease. Therefore, it is necessary to identify such changes in the individual layers of the retina so as to provide useful information for disease diagnosis. In this study, we propose using an acoustic radiation force optical coherence elastography (ARF-OCE) system to dynamically excite the porcine retina and detect the vibrational displacement with phase resolved Doppler optical coherence tomography. Due to the vibrational mechanism of the tissue response, the image quality is compromised during elastogram acquisition. In order to properly analyze the images, all signals, including the trigger and control signals for excitation, as well as detection and scanning signals, are synchronized within the OCE software and are kept consistent between frames, making it possible for easy phase unwrapping and elasticity analysis. In addition, a combination of segmentation algorithms is used to accommodate the compromised image quality. An automatic 3D segmentation method has been developed to isolate and measure the relative elasticity of every individual retinal layer. Two different segmentation schemes based on random walker and dynamic programming are implemented. The algorithm has been validated using a 3D region of the porcine retina, where individual layers have been isolated and analyzed using statistical methods. The errors compared to manual segmentation will be calculated.

  8. FDTD based model of ISOCT imaging for validation of nanoscale sensitivity (Conference Presentation)

    Science.gov (United States)

    Eid, Aya; Zhang, Di; Yi, Ji; Backman, Vadim

    2017-02-01

    Many of the earliest structural changes associated with neoplasia occur on the micro and nanometer scale, and thus appear histologically normal. Our group has established Inverse Spectroscopic OCT (ISOCT), a spectral based technique to extract nanoscale sensitive metrics derived from the OCT signal. Thus, there is a need to model light transport through relatively large volumes (< 50 um^3) of media with nanoscale level resolution. Finite Difference Time Domain (FDTD) is an iterative approach which directly solves Maxwell's equations to robustly estimate the electric and magnetic fields propagating through a sample. The sample's refractive index for every spatial voxel and wavelength are specified upon a grid with voxel sizes on the order of λ/20, making it an ideal modelling technique for nanoscale structure analysis. Here, we utilize the FDTD technique to validate the nanoscale sensing ability of ISOCT. The use of FDTD for OCT modelling requires three components: calculating the source beam as it propagates through the optical system, computing the sample's scattered field using FDTD, and finally propagating the scattered field back through the optical system. The principles of Fourier optics are employed to focus this interference field through a 4f optical system and onto the detector. Three-dimensional numerical samples are generated from a given refractive index correlation function with known parameters, and subsequent OCT images and mass density correlation function metrics are computed. We show that while the resolvability of the OCT image remains diffraction limited, spectral analysis allows nanoscale sensitive metrics to be extracted.

  9. Automatic detection and counting of cattle in UAV imagery based on machine vision technology (Conference Presentation)

    Science.gov (United States)

    Rahnemoonfar, Maryam; Foster, Jamie; Starek, Michael J.

    2017-05-01

    Beef production is the main agricultural industry in Texas, and livestock are managed in pasture and rangeland which are usually huge in size, and are not easily accessible by vehicles. The current research method for livestock location identification and counting is visual observation which is very time consuming and costly. For animals on large tracts of land, manned aircraft may be necessary to count animals which is noisy and disturbs the animals, and may introduce a source of error in counts. Such manual approaches are expensive, slow and labor intensive. In this paper we study the combination of small unmanned aerial vehicle (sUAV) and machine vision technology as a valuable solution to manual animal surveying. A fixed-wing UAV fitted with GPS and digital RGB camera for photogrammetry was flown at the Welder Wildlife Foundation in Sinton, TX. Over 600 acres were flown with four UAS flights and individual photographs used to develop orthomosaic imagery. To detect animals in UAV imagery, a fully automatic technique was developed based on spatial and spectral characteristics of objects. This automatic technique can even detect small animals that are partially occluded by bushes. Experimental results in comparison to ground-truth show the effectiveness of our algorithm.

  10. Fiber-based tissue identification for electrode placement in deep brain stimulation neurosurgery (Conference Presentation)

    Science.gov (United States)

    DePaoli, Damon T.; Lapointe, Nicolas; Goetz, Laurent; Parent, Martin; Prudhomme, Michel; Cantin, Léo.; Galstian, Tigran; Messaddeq, Younès.; Côté, Daniel C.

    2016-03-01

    Deep brain stimulation's effectiveness relies on the ability of the stimulating electrode to be properly placed within a specific target area of the brain. Optical guidance techniques that can increase the accuracy of the procedure, without causing any additional harm, are therefore of great interest. We have designed a cheap optical fiber-based device that is small enough to be placed within commercially available DBS stimulating electrodes' hollow cores and that is capable of sensing biological information from the surrounding tissue, using low power white light. With this probe we have shown the ability to distinguish white and grey matter as well as blood vessels, in vitro, in human brain samples and in vivo, in rats. We have also repeated the in vitro procedure with the probe inserted in a DBS stimulating electrode and found the results were in good agreement. We are currently validating a second fiber optic device, with micro-optical components, that will result in label free, molecular level sensing capabilities, using CARS spectroscopy. The final objective will be to use this data in real time, during deep brain stimulation neurosurgery, to increase the safety and accuracy of the procedure.

  11. The reliability of differentiating neurogenic claudication from vascular claudication based on symptomatic presentation.

    Science.gov (United States)

    Nadeau, Mélissa; Rosas-Arellano, M Patricia; Gurr, Kevin R; Bailey, Stewart I; Taylor, David C; Grewal, Ruby; Lawlor, D Kirk; Bailey, Chris S

    2013-12-01

    Intermittent claudication can be neurogenic or vascular. Physicians use a profile based on symptom attributes to differentiate the 2 types of claudication, and this guides their investigations for diagnosis of the underlying pathology. We evaluated the validity of these symptom attributes in differentiating neurogenic from vascular claudication. Patients with a diagnosis of lumbar spinal stenosis (LSS) or peripheral vascular disease (PVD) who reported claudication answered 14 questions characterizing their symptoms. We determined the sensitivity, specificity and positive and negative likelihood ratios (PLR and NLR) for neurogenic and vascular claudication for each symptom attribute. We studied 53 patients. The most sensitive symptom attribute to rule out LSS was the absence of "triggering of pain with standing alone" (sensitivity 0.97, NLR 0.050). Pain alleviators and symptom location data showed a weak clinical significance for LSS and PVD. Constellation of symptoms yielded the strongest associations: patients with a positive shopping cart sign whose symptoms were located above the knees, triggered with standing alone and relieved with sitting had a strong likelihood of neurogenic claudication (PLR 13). Patients with symptoms in the calf that were relieved with standing alone had a strong likelihood of vascular claudication (PLR 20.0). The classic symptom attributes used to differentiate neurogenic from vascular claudication are at best weakly valid independently. However, certain constellation of symptoms are much more indicative of etiology. These results can guide general practitioners in their evaluation of and investigation for claudication.

  12. Terahertz wireless communication based on InP-related devices (Conference Presentation)

    Science.gov (United States)

    Lee, Eui Su; Kim, Hyun-Soo; Park, Jeong-Woo; Park, Dong Woo; Park, Kyung Hyun

    2017-02-01

    Recently, a wide interest has been gathered in using terahertz (THz) waves as the carrier waves for the next generation of broadband wireless communications. Upon this objective, the photonics technologies are very attractive for their usefulness in signal generations, modulations and detections with enhanced bandwidth and data rates, and the readiness in combining to the existing fiber-optic or wireless networks. In this paper, as a preliminary step toward the THz wireless communications, a THz wireless interconnection system with a broadband antenna-integrated uni-traveling-carrier photodiode (UTC-PD) and a Shottky-barrier diode (SBD) module will be presented. In our system, optical beating signals are generated and digitally modulated by the optical intensity modulator driven by a pulse pattern generator (PPG). As the receiver a SBD and an IF filter followed by a low-noise preamplifier and a limiting amplifier was used. With a 6-mA photocurrent of the UTC-PD which corresponds to the transmitter output power of about 30 μW at 280 GHz, an error-free (BERdefinition serial digital interface format was successfully transmitted over a wireless link.

  13. DVT presentations to an emergency department: a study of guideline based care and decision making

    LENUS (Irish Health Repository)

    Lillis, D

    2016-02-01

    Pre-test probability scoring and blood tests for deep venous thrombosis (DVT) assessment are sensitive, but not specific leading to increased demands on radiology services. Three hundred and eighty-five patients presenting to an Emergency Department (ED), with suspected DVT, were studied to explore our actual work-up of patients with possible DVT relating to risk stratification, further investigation and follow up. Of the 205 patients with an initially negative scan, 36 (17.6%) were brought for review to the ED Consultant clinic. Thirty-four (16.6%) patients underwent repeat compression ultrasound with 5 (2.4%) demonstrating a DVT on the second scan. Repeat compression ultrasound scans were performed on 34 (16.6%) patients with an initially negative scan, with essentially the same diagnostic yield as other larger studies where 100% of such patients had repeat scanning. Where there is ongoing concern, repeat above-knee compression ultrasound within one week will pick up a small number of deep venous thromboses.

  14. A present status of IECF based linear neutron source in CPP-IPR

    International Nuclear Information System (INIS)

    Borgahain, D.; Buzarbaruah, N.; Mohanty, S.R.

    2015-01-01

    In recent years Inertial Electrostatic Confinement Fusion (IECF) device draws a considerable attention because of its application in neutron activation analysis, land mind detection, plasma space propulsion etc. It is a relatively compact device having the advantage of confining ions in converging electrostatic fields for fusion purposes. While designing the grid structure of IECF device we simulated the electric potential distributions and ion trajectories in it using SIMION 8.0 code. The results predicted ion recirculations for different grid transparencies of inner electrode and a better fusion is expected with optimum transparency in the range of 84%-92%. Monte-Carlo N-particle simulation (MCNP) for estimating the neutron radiation mapping for our IECF experiment was also done. We have found out that a local shield of 35cm thick HDPE around IECF device seen to be sufficient for keeping the neutron and gamma dose rate levels at human occupied places far below the regulatory limit of 1μSv/hr (single particle) and 10μSv/hr (both particle). Details of the results will be presented in the paper

  15. Performance test and analysis to the prototype of fiber-based portable large area surface contamination monitor

    International Nuclear Information System (INIS)

    Qu Yantao; Liu Yang; Wang Wei; Wang Ying; Hou Jie

    2013-01-01

    The feasibility was studied of using large area plastic scintillation (sensitive area up to 1200 cm 2 ) and wavelength-shifting fiber (WLS) to measure β surface contamination that led to a tentative adoption of direct coupling method of wavelength-shifting fiber array and plastic scintillator. Based on above, a calculation program was established, by which the optical transmission was simulated enabling optimizations to the design of the system such as the size of the plastic scintillator, the quantity of the wavelength-shifting fiber and the configuration mode of the wavelength-shifting fiber. As a result, a special experimental prototype was developed and tested. Results prove that the sensitive detection area is up to 1200 cm 2 , the detection efficiency is about 15.4%, the inconsistency of the different sensitive area is about 9.7%, and the minimum detectable limit is about 0.05 Bq/cm 2 , all of which indicate that the experimental prototype could satisfy requirements of surface pollution monitoring for both normal and accident conditions. (authors)

  16. Stock identity of beluga (Delphinapterus leucas in Eastern Canada and West Greenland based on organochlorine contaminants in their blubber

    Directory of Open Access Journals (Sweden)

    Stuart Innes

    2002-07-01

    Full Text Available Belugas (Delphinapterus leucas caught by hunters from various hamlets in the Arctic differed in the concentrations of organochlorine contaminants in their blubber. By applying Canonical Discriminant Analysis (CDA it was possible to separate all seven sampling locations from each other. Over 90% of the samples could be classified back to their landing location based on the data transformations developed by CDA. This analysis suggested that “stock” or management unit for belugas is best described by the culturally transmitted behaviour of their migration route. The analysis also provides evidence that most belugas caught by hunters from Grise Fiord are not the same as belugas caught while migrating along West Greenland; that some belugas caught in Sanikiluaq are not the same as beluga caught in the Nastapoka River estuary; and that the belugas caught in Kimmirut are not the same as belugas caught in Cumberland Sound. There is a need to redefine the stock descriptions of some belugas in Canada and Greenland.

  17. Habitat type-based bioaccumulation and risk assessment of metal and As contamination in earthworms, beetles and woodlice

    International Nuclear Information System (INIS)

    Vermeulen, Frouke; Van den Brink, Nico W.; D'Have, Helga; Mubiana, Valentine K.; Blust, Ronny; Bervoets, Lieven; De Coen, Wim

    2009-01-01

    The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way. - Our study provided essential insights into habitat-specific accumulation patterns with respect to factors influencing metal bioaccumulation, BAFs, and site-specific risk assessment.

  18. Habitat type-based bioaccumulation and risk assessment of metal and As contamination in earthworms, beetles and woodlice

    Energy Technology Data Exchange (ETDEWEB)

    Vermeulen, Frouke, E-mail: frouke.vermeulen@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Van den Brink, Nico W., E-mail: nico.vandenbrink@wur.n [Alterra, Wageningen UR, Box 47, NL6700AA Wageningen (Netherlands); D' Have, Helga [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Mubiana, Valentine K., E-mail: kayawe.mubiana@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Blust, Ronny, E-mail: ronny.blust@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Bervoets, Lieven, E-mail: lieven.bervoets@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); De Coen, Wim, E-mail: wim.decoen@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

    2009-11-15

    The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way. - Our study provided essential insights into habitat-specific accumulation patterns with respect to factors influencing metal bioaccumulation, BAFs, and site-specific risk assessment.

  19. Pixel based SHG probes of extracellular matrix (ECM) alterations in ovarian cancer (Conference Presentation)

    Science.gov (United States)

    Campbell, Kirby R.; Chaudhary, Rajeev; Handel, Julia; Campagnola, Paul J.

    2017-02-01

    Remodeling of the extracellular matrix in human ovarian cancer, can be reflected in increased collagen concentration, changes in alignment and/or up-regulation of different collagen isoforms, including Col III. Using fibrillar gel models, we demonstrate that Col I and Col III can be quantitatively distinguished by 3 distinct SHG polarization specific metrics: i) determination of helical pitch angle via the single axis molecular model, ii) dipole alignment via anisotropy, and iii) chirality via SHG circular dichroism (SHG-CD). These sub-resolution differentiations are possible due to differences in the α helix angles of the two isoforms, which co-mingle in the same fibrils. We also investigated the mechanism of the SHG-CD response and show that unlike conventional CD, it is dominated by electric dipole interactions and is consistent with the two state SHG model. We further applied these 3 polarization resolved analyses to human normal, high risk, benign tumors, and malignant human ovarian tissues. We found that these tissues could all be differentiated by these metrics, where high grade tissues had analogous α-helical pitch angles to the in the Col I/Col III gel model. This confirms literature suggestions based on immunofluorescence and gene expression that Col III is up-regulated in high grade ovarian cancers. The different tissues also displayed differing anisotropies, indicating the fibril assemblies are distinct and likely do not result from remodeling of existing collagen but synthesis of new collagen. Importantly, these SHG polarization methods provide structural information not otherwise possible and can serve as label-free biomarkers for ovarian and other cancers.

  20. Stripe-teeth metamaterial Al- and Nb-based rectennas (Presentation Recording)

    Science.gov (United States)

    Osgood, Richard M.; Giardini, Stephen A.; Carlson, Joel B.; Joghee, Prabhuram; O'Hayre, Ryan P.; Diest, Kenneth; Rothschild, Mordechai

    2015-09-01

    Unlike a semiconductor, where the absorption is limited by the band gap, a "microrectenna array" could theoretically very efficiently rectify any desired portion of the infrared frequency spectrum (25 - 400 THz). We investigated vertical metal-insulator-metal (MIM) diodes that rectify vertical high-frequency fields produced by a metamaterial planar stripe-teeth Al or Au array (above the diodes), similar to stripe arrays that have demonstrated near-perfect absorption in the infrared due to critical coupling [1]. Using our design rules that maximize asymmetry (and therefore the component of the electric field pointed into the substrate, analogous to Second Harmonic Generation), we designed, fabricated, and analyzed these metamaterial-based microrectenna arrays. NbOx and Al2O3 were produced by anodization and ALD, respectively. Smaller visible-light Pt-NbOx-Nb rectennas have produced output power when illuminated by visible (514 nm) light [2]. The resonances of these new Au/NbOx/Nb and Al/Al2O3/Al microrectenna arrays, with larger dimensions and more complex nanostructures than in Ref. 1, were characterized by microscopic FTIR microscopy and agreed well with FDTD models, once the experimental refractive index values were entered into the model. Current-voltage measurements were carried out, showed that the Al/Al2O3/Al diodes have very large barrier heights and breakdown voltages, and were compared to our model of the MIM diode. We calculate expected THz-rectification using classical [3] and quantum [4] rectification models, and compare to measurements of direct current output, under infrared illumination. [1] C. Wu, et. al., Phys. Rev. B 84 (2011) 075102. [2] R. M. Osgood III, et. al., Proc. SPIE 8096, 809610 (2011). [3] A. Sanchez, et. al., J. Appl. Phys. 49 (1978) 5270. [4] J. R. Tucker and M. J. Feldman, Rev. of Mod. Phys. 57, (1985)1055.

  1. OCT-based profiler for automating ocular surface prosthetic fitting (Conference Presentation)

    Science.gov (United States)

    Mujat, Mircea; Patel, Ankit H.; Maguluri, Gopi N.; Iftimia, Nicusor V.; Patel, Chirag; Agranat, Josh; Tomashevskaya, Olga; Bonte, Eugene; Ferguson, R. Daniel

    2016-03-01

    The use of a Prosthetic Replacement of the Ocular Surface Environment (PROSE) device is a revolutionary treatment for military patients that have lost their eyelids due to 3rd degree facial burns and for civilians who suffer from a host of corneal diseases. However, custom manual fitting is often a protracted painful, inexact process that requires multiple fitting sessions. Training for new practitioners is a long process. Automated methods to measure the complete corneal and scleral topology would provide a valuable tool for both clinicians and PROSE device manufacturers and would help streamline the fitting process. PSI has developed an ocular anterior-segment profiler based on Optical Coherence Tomography (OCT), which provides a 3D measure of the surface of the sclera and cornea. This device will provide topography data that will be used to expedite and improve the fabrication process for PROSE devices. OCT has been used to image portions of the cornea and sclera and to measure surface topology for smaller contact lenses [1-3]. However, current state-of-the-art anterior eye OCT systems can only scan about 16 mm of the eye's anterior surface, which is not sufficient for covering the sclera around the cornea. In addition, there is no systematic method for scanning and aligning/stitching the full scleral/corneal surface and commercial segmentation software is not optimized for the PROSE application. Although preliminary, our results demonstrate the capability of PSI's approach to generate accurate surface plots over relatively large areas of the eye, which is not currently possible with any other existing platform. Testing the technology on human volunteers is currently underway at Boston Foundation for Sight.

  2. Characteristics of cancer patients presenting to an integrative medicine practice-based research network.

    Science.gov (United States)

    Edman, Joel S; Roberts, Rhonda S; Dusek, Jeffery A; Dolor, Rowena; Wolever, Ruth Q; Abrams, Donald I

    2014-09-01

    To assess psychosocial characteristics, symptoms and reasons for seeking integrative medicine (IM) care in cancer patients presenting to IM clinical practices. A survey of 3940 patients was conducted at 8 IM sites. Patient reported outcome measures were collected and clinicians provided health status data. This analysis compares 353 participants self-identified as cancer patients with the larger noncancer cohort. Mean age of the cancer cohort was 55.0 years. Participants were predominantly white (85.9%), female (76.4%), and well educated (80.5% completed college). For 15.2% of cancer patients, depression scores were consistent with depressive symptoms, and average scores for perceived stress were higher than normal, but neither were significantly different from noncancer patients. The most prevalent comorbid symptoms were chronic pain (39.8%), fatigue (33.5%), and insomnia (23.3%). In the cancer cohort, perceived stress was significantly associated with depression, fatigue, insomnia, pain, and QOL. Cancer patients who chose an IM clinical practice "seeking healthcare settings that address spirituality as an aspect of care" had significantly higher levels of perceived stress, depression, and pain than those not selecting this reason. Demographic characteristics, depression scores, perceived stress scores, and reasons for seeking integrative cancer care were not significantly different between cancer patients and noncancer patients. Perceived stress may be an important indicator of QOL. The association of perceived stress, depression and pain with seeking spirituality suggests that providing IM interventions, such as effective stress management techniques and pastoral or spiritual counseling, may be helpful to patients living with cancer. © The Author(s) 2014.

  3. Nonlinear modeling of ferroelectric-ferromagnetic composites based on condensed and finite element approaches (Presentation Video)

    Science.gov (United States)

    Ricoeur, Andreas; Lange, Stephan; Avakian, Artjom

    2015-04-01

    Magnetoelectric (ME) coupling is an inherent property of only a few crystals exhibiting very low coupling coefficients at low temperatures. On the other hand, these materials are desirable due to many promising applications, e.g. as efficient data storage devices or medical or geophysical sensors. Efficient coupling of magnetic and electric fields in materials can only be achieved in composite structures. Here, ferromagnetic (FM) and ferroelectric (FE) phases are combined e.g. including FM particles in a FE matrix or embedding fibers of the one phase into a matrix of the other. The ME coupling is then accomplished indirectly via strain fields exploiting magnetostrictive and piezoelectric effects. This requires a poling of the composite, where the structure is exposed to both large magnetic and electric fields. The efficiency of ME coupling will strongly depend on the poling process. Besides the alignment of local polarization and magnetization, it is going along with cracking, also being decisive for the coupling properties. Nonlinear ferroelectric and ferromagnetic constitutive equations have been developed and implemented within the framework of a multifield, two-scale FE approach. The models are microphysically motivated, accounting for domain and Bloch wall motions. A second, so called condensed approach is presented which doesn't require the implementation of a spatial discretisation scheme, however still considering grain interactions and residual stresses. A micromechanically motivated continuum damage model is established to simulate degradation processes. The goal of the simulation tools is to predict the different constitutive behaviors, ME coupling properties and lifetime of smart magnetoelectric devices.

  4. Optical gain in GaAsBi-based quantum-well diode lasers (Conference Presentation)

    Science.gov (United States)

    Marko, Igor P.; Broderick, Christopher A.; Jin, Shirong; Ludewig, Peter; Stolz, Wolfgang; Volz, Kerstin; Rorison, Judy M.; O'Reilly, Eoin P.; Sweeney, Stephen J.

    2017-02-01

    GaAsBi offers the possibility to develop near-IR semiconductor lasers such that the spin-orbit-split-off energy (ΔSO) is greater than the bandgap (Eg) in the active region with lasing wavelengths in the datacom/telecom range of 1.3-1.6 μm. This promises to suppress the dominant efficiency-limiting loss processes as Auger recombination, involving the generation of "hot" holes in the spin-orbit split-off band (the so-called "CHSH" process), and inter-valence band absorption (IVBA), where emitted photons are re-absorbed in the active region, thereby increasing the internal optical losses and negatively impacting upon the laser characteristics being responsible for the main energy consumption. In addition to growth and fabrication processes refinement, a key aspect of efforts to continue the advancement of the GaAsBi material system for laser applications is to develop a quantitative understanding of the impact of Bi on key device parameters. In this work, we present the first experimental measurements of the absorption, spontaneous emission, and optical gain spectra of GaAsBi/AlGaAs QW lasers using a segmented contact method and a theoretical analysis of these devices, which shows good quantitative agreement with the experiment. Internal optical losses of 10-15 cm-1 and peak modal gain of 24 cm-1 are measured at threshold and a peak material gain is estimated to be 1500 cm-1 at current density of 2 kA/cm-2, which agrees well with the calculated value of 1560 cm-1. The theoretical calculations also enabled us to identify and quantify Bi composition variations across the wafer and Bi-induced inhomogeneous broadening of the optical spectra.

  5. School-Based Mental Health Programs in the United States: Present Status and a Blueprint for the Future.

    Science.gov (United States)

    Pfeiffer, Steven I.; Reddy, Linda A.

    1998-01-01

    Provides overview of sociocultural and political factors in the United States that have influenced recent interest in school-based health and mental health programs. Describes four well-known programs and presents a new framework, the Tripartite Model of School-Based Mental Health Interventions, to stimulate thinking on future programs. Addresses…

  6. Deep machine learning based Image classification in hard disk drive manufacturing (Conference Presentation)

    Science.gov (United States)

    Rana, Narender; Chien, Chester

    2018-03-01

    A key sensor element in a Hard Disk Drive (HDD) is the read-write head device. The device is complex 3D shape and its fabrication requires over thousand process steps with many of them being various types of image inspection and critical dimension (CD) metrology steps. In order to have high yield of devices across a wafer, very tight inspection and metrology specifications are implemented. Many images are collected on a wafer and inspected for various types of defects and in CD metrology the quality of image impacts the CD measurements. Metrology noise need to be minimized in CD metrology to get better estimate of the process related variations for implementing robust process controls. Though there are specialized tools available for defect inspection and review allowing classification and statistics. However, due to unavailability of such advanced tools or other reasons, many times images need to be manually inspected. SEM Image inspection and CD-SEM metrology tools are different tools differing in software as well. SEM Image inspection and CD-SEM metrology tools are separate tools differing in software and purpose. There have been cases where a significant numbers of CD-SEM images are blurred or have some artefact and there is a need for image inspection along with the CD measurement. Tool may not report a practical metric highlighting the quality of image. Not filtering CD from these blurred images will add metrology noise to the CD measurement. An image classifier can be helpful here for filtering such data. This paper presents the use of artificial intelligence in classifying the SEM images. Deep machine learning is used to train a neural network which is then used to classify the new images as blurred and not blurred. Figure 1 shows the image blur artefact and contingency table of classification results from the trained deep neural network. Prediction accuracy of 94.9 % was achieved in the first model. Paper covers other such applications of the deep neural

  7. Activity-Based Costing & Warm Fuzzies - Costing, Presentation & Framing Influences on Decision-Making ~ A Business Optimization Simulation ~

    OpenAIRE

    Harrison, David Shelby

    1998-01-01

    Activity-Based Costing is presented in accounting text books as a costing system that can be used to make valuable managerial decisions. Accounting journals regularly report the successful implementations and benefits of activity-based costing systems for particular businesses. Little experimental or empirical evidence exists, however, that has demonstrated the benefits of activity-based costing under controlled conditions. Similarly, although case studies report conditions that may or may...

  8. Redispersion of indoor surface contamination: a review

    International Nuclear Information System (INIS)

    Sansone, E.B.; Slein, M.W.

    1978-01-01

    The importance of surface contamination as a potential source of exposure to hazardous materials is discussed. Data from the literature concerning the resuspension of indoor surface contamination are presented. Reported procedures for quantitating surface contamination are compared. It is suggested that, despite its limitations, surface contamination monitoring may be useful in estimating potential risks from hazardous materials. (Auth.)

  9. Museum of Perception and Cognition website: using JavaScript to increase interactivity in Web-based presentations.

    Science.gov (United States)

    Lange, M

    1999-02-01

    The present paper introduces the Museum of Perception and Cognition website. This site offers an interactive introduction to cognitive psychology via a JavaScript-based illustration of optical illusions and a Java-based presentation of experimental paradigms. Its content and utilization as lecture support for 1st-year students at Free University of Brussels is described. This paper also endeavors to share experience we gained in Web-based lecture materials development. It introduces the Web lecturer with JavaScript features and utilization and provides him/her with a description of reusable JavaScript routines downloadable from our site that relate to more engaging, interactive, and effective Web-based presentation of course materials.

  10. Overview of contaminant arrival distributions as general evaluation requirements

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The environmental consequences of subsurface contamination problems can be completely and effectively evaluated by fulfilling the following five requirements: Determine each present or future outflow boundary of contaminated groundwater; provide the location/arrival-time distributions; provide the location/outflow-quantity distributions; provide these distributions for each individual chemical or biological constituent of environmental importance; and use the arrival distributions to determine the quantity and concentration of each contaminant that will interface with the environment as time passes. The arrival distributions on which these requirements are based provide a reference point for communication among scientists and public decision makers by enabling complicated scientific analyses to be presented as simple summary relationships

  11. Evaluation of contaminated groundwater cleanup objectives

    International Nuclear Information System (INIS)

    Arquiett, C.; Gerke, M.; Datskou, I.

    1996-01-01

    The US Department of Energy's (DOE's) Environmental Restoration Program will be responsible for remediating the approximately 230 contaminated groundwater sites across the DOE Complex. A major concern for remediation is choosing the appropriate cleanup objective. The cleanup objective chosen will influence the risk to the nearby public during and after remediation; risk to remedial and non-involved workers during remediation; and the cost of remediation. This paper discusses the trends shown in analyses currently being performed at Oak Ridge National Laboratories' (ORNL's) Center for Risk Management (CRM). To evaluate these trends, CRM is developing a database of contaminated sites. This paper examines several contaminated groundwater sites selected for assessment from CRM's data base. The sites in this sample represent potential types of contaminated groundwater sites commonly found at an installation within DOE. The baseline risk from these sites to various receptors is presented. Residual risk and risk during remediation is reported for different cleanup objectives. The cost associated with remediating to each of these objectives is also estimated for each of the representative sites. Finally, the general trends of impacts as a function of cleanup objective will be summarized. The sites examined include the Savannah River site, where there was substantial ground pollution from radionuclides, oil, coal stockpiles, and other forms of groundwater contamination. The effects of various types of groundwater contamination on various types of future user is described. 4 refs., 3 figs., 2 tabs

  12. Pathways and factors for food safety and food security at PFOS contaminated sites within a problem based learning approach.

    Science.gov (United States)

    Brambilla, Gianfranco; D'Hollander, Wendy; Oliaei, Fardin; Stahl, Thorsten; Weber, Roland

    2015-06-01

    Perfluorooctanesulfonic acid (PFOS) and related substances have been listed in Annex B of the Stockholm Convention. The implementation requires inventories of use, stockpiles, and environmental contamination including contaminated sites and measures for (risk) reduction and phase out. In most countries monitoring capacity is not available and therefore other approaches for assessment of contaminated sites are needed. Available informations about PFOS contamination in hot spot areas and its bio-accumulation in the food webs have been merged to build up a worst-case scenario We model PFOS transfer from 1 to 100ngL(-1) range in water to extensive and free-range food producing animals, also via the spread of contaminated sludges on agriculture soils. The modeling indicates that forages represented 78% of the exposure in ruminants, while soil accounted for >80% in outdoor poultry/eggs and pigs. From the carry-over rates derived from literature, in pork liver, egg, and feral fish computed concentration falls at 101, 28 and 2.7ngg(-1), respectively, under the 1ngL(-1) PFOS scenario. Assuming a major consumption of food produced from a contaminated area, advisories on egg and fish, supported by good agriculture/farming practices could abate 75% of the human food intake. Such advisories would allow people to become resilient in a PFOS contaminated area through an empowerment of the food choices, bringing the alimentary exposure toward the current Tolerable Daily Intake (TDI) of 150ngkg(-1)bodyweightd(-1) proposed by the European Food Safety Authority (EFSA). Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Electrical Tracking Formation on Silane Epoxy Resin under Various Contaminants

    Directory of Open Access Journals (Sweden)

    NFN Rochmadi

    2013-03-01

    Full Text Available Contamination at the surface of the insulator becomes a serious problem in power system operation, especially for the tropical area. Humidity and rainfall play an important role in wetness by the water at the surface of the insulator, which result in the presence of contaminant and leakage current flowing at the surface of the insulator. This leakage current will generate heat which occurs at the surface of an insulator, so that dry band area will be formed. This ultimately leads to flashover. This paper presents the influence of contaminants to leakage current and formation of electrical tracking at the surface of epoxy resin compound wit silicon rubber. The test was based on Inclined-Planed Tracking method with NH4Cl as contaminants. The industrial and coastal contaminants are used to explain the effect of contaminant at surface tracking process. The flow rate of contaminant was 0.3 ml/min. The 3.5 kV AC high voltage 50 Hz was applied to the top electrodes. It is found that industrial contamination resulting in the smallest surface leakage current is 327.6 mA. Also it is found that coastal contaminant (1420 mS/cm showed the severest damage at surface of test sample. Therefore, special treatment of the sample are needed under these conditions so that the material performance can be improved, especially against the electrical tracking.

  14. Metal contamination in urban, suburban, and country park soils of Hong Kong: A study based on GIS and multivariate statistics

    International Nuclear Information System (INIS)

    Lee, Celine Siu-lan; Li Xiangdong; Shi Wenzhong; Cheung, Sharon Ching-nga; Thornton, Iain

    2006-01-01

    The urban environment quality is of vital importance as the majority of people now live in cities. Due to the continuous urbanisation and industrialisation in many parts of the world, metals are continuously emitted into the terrestrial environment and pose a great threat on human health. An extensive survey was conducted in the highly urbanised and commercialised Hong Kong Island area (80.3 km 2 ) of Hong Kong using a systematic sampling strategy of five soil samples per km 2 in urban areas and two samples per km 2 in the suburban and country park sites (0-15 cm). The analytical results indicated that the surface soils in urban and suburban areas are enriched with metals, such as Cu, Pb, and Zn. The Pb concentration in the urban soils was found to exceed the Dutch target value. The statistical analyses using principal component analysis (PCA) and cluster analysis (CA) showed distinctly different associations among trace metals and the major elements (Al, Ca, Fe, Mg, Mn) in the urban, suburban, and country park soils. Soil pollution maps of trace metals (Cd, Co, Cr, Cu, Ni, Pb, and Zn) in the surface soils were produced based on geographical information system (GIS) technology. The hot-spot areas of metal contamination were mainly concentrated in the northern and western parts of Hong Kong Island, and closely related to high traffic conditions. The Pb isotopic composition of the urban, suburban, and country park soils showed that vehicular emissions were the major anthropogenic sources for Pb. The 206 Pb/ 207 Pb and 208 Pb/ 207 Pb ratios in soils decreased as Pb concentrations increased in a polynomial line (degree = 2)

  15. Reconditioning contaminated gravel

    International Nuclear Information System (INIS)

    Walsh, H.; Bowers, J.S.; Cadwell, K.

    1995-02-01

    Lawrence Livermore National Laboratory (LLNL) has developed a portable screening system that will recondition radioactively contaminated gravel in the field. The separation technique employed by this system removes dirt, contaminated debris, and other fine particles from gravel. At LLNL, gravel is used in conjunction with the experimental testing of explosives to reduce shock wave propagation. The gravel surrounds the experimental device and buffers the energy generated from the explosion. During an explosion, some of the gravel is broken down into small particles and mixed with contaminants. Contaminants in the used gravel originate from metal sheathing and other parts comprising, the experimental device. These contaminants may consist of radionuclides and metals that are considered hazardous by the State of California when disposed. This paper describes the process that conveys contaminated material into the screener system, sprays the material with recycled water or other mild cleaning chemicals, and separates particles based on size. Particles greater than a specified size are discharged out of the screener separator and recycled back into use, thereby reducing the amount of mixed waste generated and minimizing the need for new gravel. The fines or silt are flushed out of the separator with the water and are removed from the water and consolidated into a drum with the use of a hydrocyclone separator and drum decant system. Because the water in the spray system is recycled, minimal makeup water is needed. The system monitors pH and total dissolved solids

  16. Cloud-based Monte Carlo modelling of BSSRDF for the rendering of human skin appearance (Conference Presentation)

    Science.gov (United States)

    Doronin, Alexander; Rushmeier, Holly E.; Meglinski, Igor; Bykov, Alexander V.

    2016-03-01

    We present a new Monte Carlo based approach for the modelling of Bidirectional Scattering-Surface Reflectance Distribution Function (BSSRDF) for accurate rendering of human skin appearance. The variations of both skin tissues structure and the major chromophores are taken into account correspondingly to the different ethnic and age groups. The computational solution utilizes HTML5, accelerated by the graphics processing units (GPUs), and therefore is convenient for the practical use at the most of modern computer-based devices and operating systems. The results of imitation of human skin reflectance spectra, corresponding skin colours and examples of 3D faces rendering are presented and compared with the results of phantom studies.

  17. Reproductive performance in East Greenland polar bears (Ursus maritimus) may be affected by organohalogen contaminants as shown by physiologically-based pharmacokinetic (PBPK) modelling.

    Science.gov (United States)

    Sonne, Christian; Gustavson, Kim; Rigét, Frank F; Dietz, Rune; Birkved, Morten; Letcher, Robert J; Bossi, Rossana; Vorkamp, Katrin; Born, Erik W; Petersen, Gitte

    2009-12-01

    Polar bears (Ursus maritimus) feed mainly on ringed seal (Phoca hispida) and consume large quantities of blubber and consequently have one of the highest tissue concentrations of organohalogen contaminants (OHCs) worldwide. In East Greenland, studies of OHC time trends and organ system health effects, including reproductive, were conducted during 1990-2006. However, it has been difficult to determine the nature of the effects induced by OHC exposures on wild caught polar bears using body burden data and associated changes in reproductive organs and systems. We therefore conducted a risk quotient (RQ) evaluation to more quantitatively evaluate the effect risk on reproduction (embryotoxicity and teratogenicity) based on the critical body residue (CBR) concept and using a physiologically-based pharmacokinetic (PBPK) model. We applied modelling approaches to PCBs, p,p'-DDE, dieldrin, oxychlordane, HCHs, HCB, PBDEs and PFOS in East Greenland polar bears based on known OHC pharmacokinetics and dynamics in laboratory rats (Rattus rattus). The results showed that subcutaneous adipose tissue concentrations of dieldrin (range: 79-1271 ng g(-1) lw) and PCBs (range: 4128-53,923 ng g(-1) lw) reported in bears in the year 1990 were in the range to elicit possible adverse health effects on reproduction in polar bears in East Greenland (all RQs > or = 1). Similar results were found for PCBs (range: 1928-17,376 ng g(-1) lw) and PFOS (range: 104-2840 ng g(-1) ww) in the year 2000 and for dieldrin (range: 43-640 ng g(-1) lw), PCBs (range: 3491-13,243 ng g(-1) lw) and PFOS (range: 1332-6160 ng g(-1) ww) in the year 2006. The concentrations of oxychlordane, DDTs, HCB and HCHs in polar bears resulted in RQspolar bears correlated to OHC exposure are supported by the present study. This study also indicates that PBPK models may be a supportive tool in the evaluation of possible OHC-mediated health effects for Arctic wildlife.

  18. A cost-saving statistically based screening technique for focused sampling of a lead-contaminated site

    International Nuclear Information System (INIS)

    Moscati, A.F. Jr.; Hediger, E.M.; Rupp, M.J.

    1986-01-01

    High concentrations of lead in soils along an abandoned railroad line prompted a remedial investigation to characterize the extent of contamination across a 7-acre site. Contamination was thought to be spotty across the site reflecting its past use in battery recycling operations at discrete locations. A screening technique was employed to delineate the more highly contaminated areas by testing a statistically determined minimum number of random samples from each of seven discrete site areas. The approach not only quickly identified those site areas which would require more extensive grid sampling, but also provided a statistically defensible basis for excluding other site areas from further consideration, thus saving the cost of additional sample collection and analysis. The reduction in the number of samples collected in ''clean'' areas of the site ranged from 45 to 60%

  19. Development of a low cost, GPS-based upgrade to a standard handheld gamma detector for mapping environmental radioactive contamination.

    Science.gov (United States)

    Paridaens, J

    2006-02-01

    A low cost extension to a standard handheld radiation monitor was developed, allowing one to perform outdoor georeferenced gamma measurements. It consists of a commercial wireless Bluetooth GPS receiver, a commercial RS-232 to Bluetooth converter combined with a standard Bluetooth enabled pocket personal computer (PPC). The system is intended for use in difficult to access areas, typically for foot campaigns. As the operator walks, a straightforward homemade visual basic program alternately reads GPS position and gamma dose rate into the PPC, creating a data log. This allows a single operator on foot to map between 50 and 200 ha of environmental radiation per day in very rugged areas, depending on the accessibility of the terrain and the detail required. On a test field with known contamination, a spatial precision of about 5-10 m was obtainable. The device was also used to reveal complex contamination patterns in the flooding zones of a radioactively contaminated small river.

  20. Modeling for Airborne Contamination

    International Nuclear Information System (INIS)

    F.R. Faillace; Y. Yuan

    2000-01-01

    walls. The gamma-ray scattering properties of concrete are sufficiently similar to those of the host rock and proposed insert material; use of concrete will have no significant impact on the conclusions. The information in this report is presented primarily for use in performing pre-closure radiological safety evaluations of radiological contaminants, but it may also be used to develop strategies for contaminant leak detection and monitoring in the MGR. Included in this report are the methods for determining the source terms and release fractions, and mathematical models and model parameters for contaminant transport and distribution within the repository. Various particle behavior mechanisms that affect the transport of contaminant are included. These particle behavior mechanisms include diffusion, settling, resuspension, agglomeration and other deposition mechanisms

  1. Th biodistribution in internal contamination of animals

    International Nuclear Information System (INIS)

    Ciubotariu, M.; Danis, A.; Dumitrescu, G.; Cucu, M.

    1999-01-01

    body from a non-contaminated rat and a solution calibrated in Th. The obtained results put into evidence that the Th was retained in all the vital organs of the contaminated rats, particularly in lung, liver, stomach and small intestine. All the contaminated rats have presented a non-uniform Th distribution in the investigated organs excepting the one which was sacrificed 2 days after contamination. In its organs Th inclusions were present. Their Th concentration were ranging from 1 ppm up to 24 ppm. We think that the rejection reaction of the contaminant element by the rats organism was stronger on the first days after contamination and, as a consequence, the Th was gathered in inclusions, as 'intruder' element. In time, these inclusions were 'washed' by blood and then eliminated. From the point of view of the medical state, the blood test revealed the normal values of the hemoglobin and a exponential increase of the leucocyte values (leucocytosis) without toxic granules in comparison with the U internal contamination where the blood test revealed granular cytopenia and acute leukopenia with toxic granules. In the next stage, we shall try to find a correlation between the ingested Th amount and the ones retained and eliminated by rats. For that, we must investigate the Th elimination through urine and excrements. We must specify that our results obtained in the studies on the U or Th internal contamination can be used only as a discussion based in order to think out a plan for a systematic biological investigation on the internal contamination in which a sufficient number of subjects must be used for a good statistics. (authors)

  2. Regenerable Air Purification System for Gas-Phase Contaminant Control

    Science.gov (United States)

    Constantinescu, Ileana C.; Finn, John E.; LeVan, M. Douglas; Lung, Bernadette (Technical Monitor)

    2000-01-01

    Tests of a pre-prototype regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an adsorbent column have been performed at NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. During the normal operation mode, contaminants are removed from the air on the column. Regeneration of the column is performed on-line. During regeneration, contaminants are displaced and destroyed inside the closed oxidation loop. In this presentation we discuss initial experimental results for the performance of RAPS in the removal and treatment of several important spacecraft contaminant species from air.

  3. Fall 1998 200 East area biological vector contamination report

    International Nuclear Information System (INIS)

    CONNELL, D.J.

    1999-01-01

    The purpose of this report is to document the investigation into the cause of the spread of radioactive contamination in September and October 1998 at the Hanford Site's 200 East Area and its subsequent spread to the City of Richland Landfill; identify the source of the contamination; and present corrective actions. The focus and thrust of managing the incident was based on the need to accomplish the following, listed in order of importance: (1) protect the health and safety of the Site workers and the public; (2) contain and control the spread of contamination; (3) identify the source of contamination and the pathways for its spread; and (4) identify the causal factors enabling the contamination

  4. Fall 1998 200 East area biological vector contamination report

    Energy Technology Data Exchange (ETDEWEB)

    CONNELL, D.J.

    1999-03-17

    The purpose of this report is to document the investigation into the cause of the spread of radioactive contamination in September and October 1998 at the Hanford Site's 200 East Area and its subsequent spread to the City of Richland Landfill; identify the source of the contamination; and present corrective actions. The focus and thrust of managing the incident was based on the need to accomplish the following, listed in order of importance: (1) protect the health and safety of the Site workers and the public; (2) contain and control the spread of contamination; (3) identify the source of contamination and the pathways for its spread; and (4) identify the causal factors enabling the contamination.

  5. Human urine-based therapeutics in Spain from the early 20th century to the present: a historical literature overview and a present-day case study.

    Science.gov (United States)

    Vallejo, José Ramón; Aparicio Mena, Alfonso J; González, José Antonio

    2017-06-01

    Human urine is currently the subject of biomedical investigations as a potential therapeutic resource and it continues to be used in remedies in different cultures and societies, including the Spanish culture. In this study we gather etnomedical knowledge about urotherapy and determine their associated symbolisms in Spain. A literature overview and a case study were carried out to compile urine-based remedies and as a direct analysis of symbolic systems. Urotherapy is widespread in Spanish folk medicine. Among the 204 collected remedies, those related to treatment of diseases or skin conditions predominate (63%). Remedies have been reported for the treatment of skin diseases such as eczema, chloasma, alopecia, etc. to treat or alleviate burns, chilblains, wounds or skin chapping, and as a treatment of venomous bites. Most of the collected remedies have an associated naturalist symbolism, based on local traditions and the transmission of empirical initial knowledge. The use of urine in Spain is a result of the interaction of two types of practice: a local and traditional urotherapy, rural and with a utilitarian purpose, and a technical urotherapy, limited to an urban environment and a naturopathic medicine.