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Sample records for net environmental sampling

  1. Environmental sampling

    Energy Technology Data Exchange (ETDEWEB)

    Puckett, J.M.

    1998-12-31

    Environmental Sampling (ES) is a technology option that can have application in transparency in nuclear nonproliferation. The basic process is to take a sample from the environment, e.g., soil, water, vegetation, or dust and debris from a surface, and through very careful sample preparation and analysis, determine the types, elemental concentration, and isotopic composition of actinides in the sample. The sample is prepared and the analysis performed in a clean chemistry laboratory (CCL). This ES capability is part of the IAEA Strengthened Safeguards System. Such a Laboratory is planned to be built by JAERI at Tokai and will give Japan an intrinsic ES capability. This paper presents options for the use of ES as a transparency measure for nuclear nonproliferation.

  2. RadNet (Environmental Radiation Ambient Monitoring System)

    Data.gov (United States)

    U.S. Environmental Protection Agency — RadNet, formerly Environmental Radiation Ambient Monitoring System (ERAMS), is a national network of monitoring stations that regularly collect air, precipitation,...

  3. Environmental impact analysis of aquaculture in net cages in a ...

    African Journals Online (AJOL)

    Environmental impact analysis of aquaculture in net cages in a Brazilian water reservoir, based in zooplankton communities. Maria Cristina Crispim, Karla Patrícia Ponte Araújo, Hênio do Nascimento Melo Júnior ...

  4. Evaluation of common methods for sampling invertebrate pollinator assemblages: net sampling out-perform pan traps.

    Directory of Open Access Journals (Sweden)

    Tony J Popic

    Full Text Available Methods for sampling ecological assemblages strive to be efficient, repeatable, and representative. Unknowingly, common methods may be limited in terms of revealing species function and so of less value for comparative studies. The global decline in pollination services has stimulated surveys of flower-visiting invertebrates, using pan traps and net sampling. We explore the relative merits of these two methods in terms of species discovery, quantifying abundance, function, and composition, and responses of species to changing floral resources. Using a spatially-nested design we sampled across a 5000 km(2 area of arid grasslands, including 432 hours of net sampling and 1296 pan trap-days, between June 2010 and July 2011. Net sampling yielded 22% more species and 30% higher abundance than pan traps, and better reflected the spatio-temporal variation of floral resources. Species composition differed significantly between methods; from 436 total species, 25% were sampled by both methods, 50% only by nets, and the remaining 25% only by pans. Apart from being less comprehensive, if pan traps do not sample flower-visitors, the link to pollination is questionable. By contrast, net sampling functionally linked species to pollination through behavioural observations of flower-visitation interaction frequency. Netted specimens are also necessary for evidence of pollen transport. Benefits of net-based sampling outweighed minor differences in overall sampling effort. As pan traps and net sampling methods are not equivalent for sampling invertebrate-flower interactions, we recommend net sampling of invertebrate pollinator assemblages, especially if datasets are intended to document declines in pollination and guide measures to retain this important ecosystem service.

  5. Environmental surveillance master sampling schedule

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, L.E.

    1997-01-01

    Environmental surveillance of the Hanford Site and surrounding areas is conducted by the Pacific Northwest National Laboratory (PNNL)(a) for the US Department of Energy (DOE). This document contains the planned 1997 schedules for routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project. In addition, Section 3.0, Biota, also reflects a rotating collection schedule identifying the year a specific sample is scheduled for collection. The purpose of these monitoring projects is to evaluate levels of radioactive and nonradioactive pollutants in the Hanford environs, as required in DOE Order 5400.1, General Environmental Protection Program, and DOE Order 5400.5, Radiation Protection of the Public and the Environment. The sampling methods will be the same as those described in the Environmental Monitoring Plan, US Department of Energy, Richland Operations Office, DOE/RL91-50, Rev. 1, US Department of Energy, Richland, Washington.

  6. Optimizing sampling design to deal with mist-net avoidance in Amazonian birds and bats.

    Directory of Open Access Journals (Sweden)

    João Tiago Marques

    Full Text Available Mist netting is a widely used technique to sample bird and bat assemblages. However, captures often decline with time because animals learn and avoid the locations of nets. This avoidance or net shyness can substantially decrease sampling efficiency. We quantified the day-to-day decline in captures of Amazonian birds and bats with mist nets set at the same location for four consecutive days. We also evaluated how net avoidance influences the efficiency of surveys under different logistic scenarios using re-sampling techniques. Net avoidance caused substantial declines in bird and bat captures, although more accentuated in the latter. Most of the decline occurred between the first and second days of netting: 28% in birds and 47% in bats. Captures of commoner species were more affected. The numbers of species detected also declined. Moving nets daily to minimize the avoidance effect increased captures by 30% in birds and 70% in bats. However, moving the location of nets may cause a reduction in netting time and captures. When moving the nets caused the loss of one netting day it was no longer advantageous to move the nets frequently. In bird surveys that could even decrease the number of individuals captured and species detected. Net avoidance can greatly affect sampling efficiency but adjustments in survey design can minimize this. Whenever nets can be moved without losing netting time and the objective is to capture many individuals, they should be moved daily. If the main objective is to survey species present then nets should still be moved for bats, but not for birds. However, if relocating nets causes a significant loss of netting time, moving them to reduce effects of shyness will not improve sampling efficiency in either group. Overall, our findings can improve the design of mist netting sampling strategies in other tropical areas.

  7. Optimizing sampling design to deal with mist-net avoidance in Amazonian birds and bats.

    Science.gov (United States)

    Marques, João Tiago; Ramos Pereira, Maria J; Marques, Tiago A; Santos, Carlos David; Santana, Joana; Beja, Pedro; Palmeirim, Jorge M

    2013-01-01

    Mist netting is a widely used technique to sample bird and bat assemblages. However, captures often decline with time because animals learn and avoid the locations of nets. This avoidance or net shyness can substantially decrease sampling efficiency. We quantified the day-to-day decline in captures of Amazonian birds and bats with mist nets set at the same location for four consecutive days. We also evaluated how net avoidance influences the efficiency of surveys under different logistic scenarios using re-sampling techniques. Net avoidance caused substantial declines in bird and bat captures, although more accentuated in the latter. Most of the decline occurred between the first and second days of netting: 28% in birds and 47% in bats. Captures of commoner species were more affected. The numbers of species detected also declined. Moving nets daily to minimize the avoidance effect increased captures by 30% in birds and 70% in bats. However, moving the location of nets may cause a reduction in netting time and captures. When moving the nets caused the loss of one netting day it was no longer advantageous to move the nets frequently. In bird surveys that could even decrease the number of individuals captured and species detected. Net avoidance can greatly affect sampling efficiency but adjustments in survey design can minimize this. Whenever nets can be moved without losing netting time and the objective is to capture many individuals, they should be moved daily. If the main objective is to survey species present then nets should still be moved for bats, but not for birds. However, if relocating nets causes a significant loss of netting time, moving them to reduce effects of shyness will not improve sampling efficiency in either group. Overall, our findings can improve the design of mist netting sampling strategies in other tropical areas.

  8. Environmental surveillance master sampling schedule

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, L.E.

    1994-02-01

    This document contains the planned 1994 schedules for routine collection of samples for the Surface Environmental Surveillance Project (SESP), Drinking Water Project, and Ground-Water Surveillance Project. Samples are routinely collected for the SESP and analyzed to determine the quality of air, surface water, soil, sediment, wildlife, vegetation, foodstuffs, and farm products at Hanford Site and surrounding communities. The responsibility for monitoring the onsite drinking water falls outside the scope of the SESP. The Hanford Environmental Health Foundation is responsible for monitoring the nonradiological parameters as defined in the National Drinking Water Standards while PNL conducts the radiological monitoring of the onsite drinking water. PNL conducts the drinking water monitoring project concurrent with the SESP to promote efficiency and consistency, utilize the expertise developed over the years, and reduce costs associated with management, procedure development, data management, quality control and reporting. The ground-water sampling schedule identifies ground-water sampling events used by PNL for environmental surveillance of the Hanford Site.

  9. Comparison of Bottomless Lift Nets and Breder Traps for Sampling Salt-Marsh Nekton

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data set contains: the length of mummichogs (Fundulus heteroclitus) caught on lift nets and Breder traps from May to September 2002; the sizes of green crabs caught...

  10. Sampling and chemical analysis in environmental samples around Nuclear Power Plants and some environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Woo; Han, Man Jung; Cho, Seong Won; Cho, Hong Jun; Oh, Hyeon Kyun; Lee, Jeong Min; Chang, Jae Sook [KORTIC, Taejon (Korea, Republic of)

    2002-12-15

    Twelve kinds of environmental samples such as soil, seawater, underground water, etc. around Nuclear Power Plants(NPPs) were collected. Tritium chemical analysis was tried for the samples of rain water, pine-needle, air, seawater, underground water, chinese cabbage, a grain of rice and milk sampled around NPPs, and surface seawater and rain water sampled over the country. Strontium in the soil that sere sampled at 60 point of district in Korea were analyzed. Tritium were sampled at 60 point of district in Korea were analyzed. Tritium were analyzed in 21 samples of surface seawater around the Korea peninsular that were supplied from KFRDI(National Fisheries Research and Development Institute). Sampling and chemical analysis environmental samples around Kori, Woolsung, Youngkwang, Wooljin Npps and Taeduk science town for tritium and strontium analysis was managed according to plans. Succeed to KINS after all samples were tried.

  11. Biological Environmental Sampling Technologies Assessment

    Science.gov (United States)

    2015-12-01

    array‐based measurements that are made on carbon ink surfaces. The instrument can process a wide variety of sample types and is targeted at...from all types of surfaces and absorb unknown liquids. The Aklus Shield system can also be used to sample debris, soil, or vegetation . For this...system is already part of the selected JBTDS system. Therefore, if the InnovaPrep system was selected, it would reduce the logistical footprint of

  12. Fish fauna associated with floating objects sampled by experimental and commercial purse nets

    Directory of Open Access Journals (Sweden)

    Enric Massutí

    1999-12-01

    Full Text Available Based on the commercial surrounding nets traditionally used in the Coryphaena hippurus fishery, we designed an experimental purse seine (64 m long and 14 m high, with a purse line and a central codend of 2 mm mesh for sampling fish fauna associated with flotsam. Taxa, number, biomass and sizes of fishes caught with both types of gear around fish aggregation devices were compared. From 63 hauls with the experimental net, we caught 11370 fishes belonging to 17 families and 26 species. In contrast, 816 fishes belonging to 7 species and 5 families were collected from 39 commercial hauls. Despite differences in number of hauls for each net, the curves of cumulative species richness showed that additional hauls could not increase the number of species collected with the commercial net. The most abundant species from experimental net catches were Trachurus picturatus, which represented over 80% of the specimens caught in spring and summer, Naucrates ductor, which represented about 50% of autumn catches, both in terms of abundance and biomass, and Seriola dumerili, which represented 46% and 21% of the samples taken in summer and autumn respectively. Seriola dumerili was also frequent in commercial net catches, in which T. picturatus did not appear, while Coryphaena hippurus and N. ductor represented more than 85% of both abundance and biomass. Large differences between the two types of net were also obtained in the mean fish weight and length frequency distributions of the catches by season. Fish caught with the experimental net ranged from 6 to 570 mm length, while fish collected from commercial hauls had a size range of 35 to 700 mm. The effectiveness of the experimental net in catching small fishes showed that it can be an optimal sampling method not only in the study of fish fauna associated with flotsam, but also in studies to catch early life stages.

  13. Development of a new multiple sampling trawl with autonomous opening/closing net control system for sampling juvenile pelagic fish

    Science.gov (United States)

    Oozeki, Yoshioki; Hu, Fuxiang; Tomatsu, Chiaki; Kubota, Hiroshi

    2012-03-01

    A new multiple layer sampling trawl with an autonomous net opening/closing control system was developed to sample pelagic juvenile fish quantitatively. The new trawl system, based on the Matsuda-Oozeki-Hu Trawl (MOHT), has a rigid-frame 3.3 m high and 2.35 m wide and five nets of 11.0 m length with a rectangular mouth of 2.22 m×1.81 m (4 m2 mouth area; large-scale prototype). A cambered V-shape depressor is hung below the frame and two bridles are attached at the midpoint of the side frames. A net-release controller is used, which not only controls the net release mechanism but also records the net depth, temperature and flow rate during net towing. The controller sends stored command signals to the net release mechanism as depth settings and/or time settings and does not require any commands from the surface through a conducting cable or by acoustic signals. Two other models were constructed before the construction of the large-scale prototype, which are a small-scale prototype (2 m2 mouth area) for testing the net release mechanism and a 1/4-scale model of the large-scale prototype for flume tank tests. Flume tank tests with the 1/4-scale model showed that the frame leaned forward at a tilt angle from 5 to 15 degrees at towing speeds from 0.8 to 1.4 m s-1. Opened nets closed smoothly and sequentially nets were completely opened when the trigger was released by the command. Net depth rarely changed even during changes in towing speed. Sea trials both by the small-scale and the large-scale prototype demonstrated the same towing characteristics expected from the flume tank tests. The newly developed multiple layer opening/closing MOHT (MOC-MOHT) is considered to be suitable for quantitative layer sampling of juvenile fish.

  14. Optimization of environmental sampling using interactive GIS.

    NARCIS (Netherlands)

    Groenigen, van J.W.; Stein, A.; Zuurbier, R.

    1997-01-01

    An interactive sampling procedure is proposed to optimize environmental risk assessment. Subsequent sampling stages were used as quantitative pre-information. With this pre-information probability maps were made using indicator kriging to direct subsequent sampling. In this way, optimal use of the

  15. Diagnostic herd sensitivity using environmental samples

    DEFF Research Database (Denmark)

    Vigre, Håkan; Josefsen, Mathilde Hartmann; Seyfarth, Anne Mette

    . In our example, the prevalence of infected pigs in each herd was estimated from the pooled samples of nasal swabs. Logistic regression was used to estimate the effect of animal prevalence on the probability to detect MRSA in the dust and air samples at herd level. The results show a significant increase...... of the within herd prevalence, and performed almost perfectly at a prevalence of 25% infected pigs (sensitivity=99%). In general, the dependence of within herd prevalence should be considered in designing surveillance programs based on environmental samples.......Due to logistic and economic benefits, the animal industry has an increased interest in using environmental samples to classify herds free of infections. For a valid interpretation of results obtained from environmental samples, the performance of the diagnostic method using these samples must...

  16. Modifications to the bottomless lift net for sampling nekton in tidal mangrove forests

    Science.gov (United States)

    McIvor, C.C.; Silverman, N.L.

    2010-01-01

    Sampling fishes in vegetated intertidal wetlands is logistically challenging. We modified the 2 ?? 3-m2 bottomless lift net developed for sampling nekton (fish and decapod crustaceans) on the surface of salt marshes for use in tidal mangrove forests with a woody (as opposed to herbaceous) underground root system. As originally designed (Rozas, Mar Ecol Prog Ser 89:287-292, 1992), the lift net was buried directly in the marsh substrate. The net was raised at slack high tide thereby encircling nekton within the enclosed area. A chain-line on the net bottom prevented escape under the net once deployed. However, when we used this same design in tidal mangrove forests, the extensive woody roots and occasional slumping sediments resulted in uneven trenches that could not be cleared effectively during sample recovery. We made 3 modifications to the original net design: (i) lined the peat trenches with aluminum channels of uniform width and depth; (ii) replaced the previous chain-line with Velcro closures that directly attached the net to the inner face of the outer wall of the aluminum channel; and (iii) removed the subtidal pan previously used for concentrating the enclosed nekton at low tide, and filled in those depressions with on-site peat. In the modified version, the aluminum trench became the only subtidal refuge available to nekton, and it was from here that we collected the sample after the forest drained. These modifications permitted high clearing efficiency (93-100%) of fin-clipped individuals of two common species of estuarine resident fishes, Kryptolebias marmoratus (mangrove rivulus) and Bathygobius soporator (frillfin goby). Additionally, the density estimates of grass shrimp (Palaemonetes spp.) increased 10-fold post-modification. ?? 2010 US Government.

  17. Bio-diversity: an effective safety net against environmental pollution.

    Science.gov (United States)

    Swaminathan, M S

    2003-01-01

    Biodiversity is the feedstock for the biotechnology industry. Hence, the conservation, enhancement and sustainable and equitable use of biodiversity should be accorded high priority in all national environment protection programmes. Lichens serve as useful indicators of environmental health. Similarly, several blue green algae help to sequester salt from water. There is need for the more widespread use of such biomonitoring and bioremediation agents. Bioprospecting research designed to identify novel metabolites must be rooted in the principle of equity in sharing benefits with the holders of traditional knowledge. There is need for greater vigil against alien invasive species, since with growing world trade in food grains and other agricultural commodities, there is an increasing possibility of introducing new pests, weeds and harmful micro-organisms. Finally, biological scientists should place emphasis on their ethical responsibility for the consequences of their research, since otherwise bioterrorism could become a major threat to human security.

  18. Enzymatic Purification of Microplastics in Environmental Samples.

    Science.gov (United States)

    Löder, Martin G J; Imhof, Hannes K; Ladehoff, Maike; Löschel, Lena A; Lorenz, Claudia; Mintenig, Svenja; Piehl, Sarah; Primpke, Sebastian; Schrank, Isabella; Laforsch, Christian; Gerdts, Gunnar

    2017-12-19

    Micro-Fourier transform infrared (micro-FTIR) spectroscopy and Raman spectroscopy enable the reliable identification and quantification of microplastics (MPs) in the lower micron range. Since concentrations of MPs in the environment are usually low, the large sample volumes required for these techniques lead to an excess of coenriched organic or inorganic materials. While inorganic materials can be separated from MPs using density separation, the organic fraction impedes the ability to conduct reliable analyses. Hence, the purification of MPs from organic materials is crucial prior to conducting an identification via spectroscopic techniques. Strong acidic or alkaline treatments bear the danger of degrading sensitive synthetic polymers. We suggest an alternative method, which uses a series of technical grade enzymes for purifying MPs in environmental samples. A basic enzymatic purification protocol (BEPP) proved to be efficient while reducing 98.3 ± 0.1% of the sample matrix in surface water samples. After showing a high recovery rate (84.5 ± 3.3%), the BEPP was successfully applied to environmental samples from the North Sea where numbers of MPs range from 0.05 to 4.42 items m-3. Experiences with different environmental sample matrices were considered in an improved and universally applicable version of the BEPP, which is suitable for focal plane array detector (FPA)-based micro-FTIR analyses of water, wastewater, sediment, biota, and food samples.

  19. Bio-diversity: an effective safety net against environmental pollution

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, M.S

    2003-12-01

    Biodiversity is the feedstock for the biotechnology industry. Hence, the conservation, enhancement and sustainable and equitable use of biodiversity should be accorded high priority in all national environment protection programmes. Lichens serve as useful indicators of environmental health. Similarly, several blue green algae help to sequester salt from water. There is need for the more widespread use of such biomonitoring and bioremediation agents. Bioprospecting research designed to identify novel metabolites must be rooted in the principle of equity in sharing benefits with the holders of traditional knowledge. There is need for greater vigil against alien invasive species, since with growing world trade in food grains and other agricultural commodities, there is an increasing possibility of introducing new pests, weeds and harmful micro-organisms. Finally, biological scientists should place emphasis on their ethical responsibility for the consequences of their research, since otherwise bioterrorism could become a major threat to human security. - The age of biological diversity serves as an impetus for the future of biotechnology.

  20. Sampling and Data Analysis for Environmental Microbiology

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Christopher J.

    2001-06-01

    A brief review of the literature indicates the importance of statistical analysis in applied and environmental microbiology. Sampling designs are particularly important for successful studies, and it is highly recommended that researchers review their sampling design before heading to the laboratory or the field. Most statisticians have numerous stories of scientists who approached them after their study was complete only to have to tell them that the data they gathered could not be used to test the hypothesis they wanted to address. Once the data are gathered, a large and complex body of statistical techniques are available for analysis of the data. Those methods include both numerical and graphical techniques for exploratory characterization of the data. Hypothesis testing and analysis of variance (ANOVA) are techniques that can be used to compare the mean and variance of two or more groups of samples. Regression can be used to examine the relationships between sets of variables and is often used to examine the dependence of microbiological populations on microbiological parameters. Multivariate statistics provides several methods that can be used for interpretation of datasets with a large number of variables and to partition samples into similar groups, a task that is very common in taxonomy, but also has applications in other fields of microbiology. Geostatistics and other techniques have been used to examine the spatial distribution of microorganisms. The objectives of this chapter are to provide a brief survey of some of the statistical techniques that can be used for sample design and data analysis of microbiological data in environmental studies, and to provide some examples of their use from the literature.

  1. The geographic diversity of nontuberculous mycobacteria isolated from pulmonary samples: an NTM-NET collaborative study.

    Science.gov (United States)

    Hoefsloot, Wouter; van Ingen, Jakko; Andrejak, Claire; Angeby, Kristian; Bauriaud, Rosine; Bemer, Pascale; Beylis, Natalie; Boeree, Martin J; Cacho, Juana; Chihota, Violet; Chimara, Erica; Churchyard, Gavin; Cias, Raquel; Daza, Rosa; Daley, Charles L; Dekhuijzen, P N Richard; Domingo, Diego; Drobniewski, Francis; Esteban, Jaime; Fauville-Dufaux, Maryse; Folkvardsen, Dorte Bek; Gibbons, Noel; Gómez-Mampaso, Enrique; Gonzalez, Rosa; Hoffmann, Harald; Hsueh, Po-Ren; Indra, Alexander; Jagielski, Tomasz; Jamieson, Frances; Jankovic, Mateja; Jong, Eefje; Keane, Joseph; Koh, Wo-Jung; Lange, Berit; Leao, Sylvia; Macedo, Rita; Mannsåker, Turid; Marras, Theodore K; Maugein, Jeannette; Milburn, Heather J; Mlinkó, Tamas; Morcillo, Nora; Morimoto, Kozo; Papaventsis, Dimitrios; Palenque, Elia; Paez-Peña, Mar; Piersimoni, Claudio; Polanová, Monika; Rastogi, Nalin; Richter, Elvira; Ruiz-Serrano, Maria Jesus; Silva, Anabela; da Silva, M Pedro; Simsek, Hulya; van Soolingen, Dick; Szabó, Nora; Thomson, Rachel; Tórtola Fernandez, Teresa; Tortoli, Enrico; Totten, Sarah E; Tyrrell, Greg; Vasankari, Tuula; Villar, Miguel; Walkiewicz, Renata; Winthrop, Kevin L; Wagner, Dirk

    2013-12-01

    A significant knowledge gap exists concerning the geographical distribution of nontuberculous mycobacteria (NTM) isolation worldwide. To provide a snapshot of NTM species distribution, global partners in the NTM-Network European Trials Group (NET) framework (www.ntm-net.org), a branch of the Tuberculosis Network European Trials Group (TB-NET), provided identification results of the total number of patients in 2008 in whom NTM were isolated from pulmonary samples. From these data, we visualised the relative distribution of the different NTM found per continent and per country. We received species identification data for 20 182 patients, from 62 laboratories in 30 countries across six continents. 91 different NTM species were isolated. Mycobacterium avium complex (MAC) bacteria predominated in most countries, followed by M. gordonae and M. xenopi. Important differences in geographical distribution of MAC species as well as M. xenopi, M. kansasii and rapid-growing mycobacteria were observed. This snapshot demonstrates that the species distribution among NTM isolates from pulmonary specimens in the year 2008 differed by continent and differed by country within these continents. These differences in species distribution may partly determine the frequency and manifestations of pulmonary NTM disease in each geographical location.

  2. Osmium in environmental samples from Northeast Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Rodushkin, Ilia [Division of Applied Geology, Lulea University of Technology, S-971 87 Lulea (Sweden); ALS Laboratory Group, ALS Analytica AB, Aurorum 10, S-977 75 Lulea (Sweden)], E-mail: ilia.rodushkin@alsglobal.com; Engstroem, Emma [Division of Applied Geology, Lulea University of Technology, S-971 87 Lulea (Sweden); Soerlin, Dieke; Ponter, Christer; Baxter, Douglas C. [ALS Laboratory Group, ALS Analytica AB, Aurorum 10, S-977 75 Lulea (Sweden)

    2007-11-01

    Osmium (Os) concentrations and {sup 187}Os/{sup 188}Os isotope abundance ratios are presented for sedimentary materials, soils, humus, plants, mushrooms, mosses and lichens collected in the vicinity of the town of Lulea, Northeast Sweden, the data for biological specimens being the first reported. Contributions from sampling and varying exposure time to the observed environmental variability were evaluated. Sedimentary materials (from both fresh and brackish water) are most elevated in radiogenic {sup 187}Os, followed by inorganic soil horizons, mushrooms and humus. The Os isotopic compositions of plants, mosses and lichens are much less radiogenic, with mean {sup 187}Os/{sup 188}Os lying within a relatively narrow 0.3-0.6 range. Significant temporal variations in Os concentrations and isotopic compositions of plant samples are attributed to integrative uptake of airborne Os with non-radiogenic composition. Measured Os concentrations in biological matrices increase in the order: small shrub leaves (blueberry and lingonberry) {<=} spruce needles {<=} mushrooms {<=} tree leaves {<=} pine needles < mosses << lichens. The concentrations found in three different species of plant were used to provide the first estimates of gaseous osmium tetroxide (OsO{sub 4}) in the environment. Though the Os content of samples from Northeast Sweden does not differ significantly from matrix-matched international reference materials (not certified for Os) of abiotic origin, the estimates of gaseous OsO{sub 4} concentrations are roughly an order of magnitude higher than have been reported for particle-bound Os in other studies. The pronounced spatial variations between relatively closely situated sites in mean {sup 187}Os/{sup 188}Os ratios for samples of the same species (presumably with the same dominating uptake mechanism) point to the presence of different local Os sources. This study therefore demonstrates that emissions of Os from automobile catalytic converters are not the only

  3. SkyGlowNet: Multi-Disciplinary Independent Student Research in Environmental Light at Night Monitoring

    Science.gov (United States)

    Craine, B. L.; Craine, E. R.; Culver, R. B.; DeBenedetti, J. C.; Flurchick, K. M.

    2014-07-01

    SkyGlowNet uses Internet-enabled sky brightness meters (iSBM) to monitor sky brightness over school sites. The data are used professionally and in STEM outreach to study natural and artificial sources of sky brightness, light pollution, energy efficiency, and environmental and health impacts of artificial night lighting. The iSBM units are owned by participating institutions and managed by faculty or students via proprietary Internet links. Student data are embargoed for two semesters to allow students to analyze data and publish results, then they are moved to a common area where students from different institutions can collaborate. The iSBM units can be set to operate automatically each night. Their data include time, sky brightness, weather conditions, and other related parameters. The data stream can be viewed and processed online or downloaded for study. SkyGlowNet is a unique, multi-disciplinary, real science program aiding research for science and non-science students.

  4. Differential efficiencies of dip-net sampling versus sampling surface-floating pupal exuviae in a biodiversity survey of Chironomidae

    Directory of Open Access Journals (Sweden)

    Leonard Charles Ferrington Jr

    2014-12-01

    Full Text Available Relative efficiencies of standard dip-net sampling (SDN versus collections of surface-floating pupal exuviae (SFPE were determined for detecting Chironomidae at catchment and site scales and at subfamily/tribe-, genus- and species-levels based on simultaneous, equal-effort sampling on a monthly basis for one year during a biodiversity assessment of Bear Run Nature Reserve. Results showed SFPE was more efficient than SDN at catchment scales for detecting both genera and species. At site scales, SDN sampling was more efficient for assessment of a first-order site. No consistent pattern, except for better efficiency of SFPE to detect Orthocladiinae genera, was observed at genus-level for two second-order sites. However, SFPE was consistently more efficient at detecting species of Orthocladiinae, Chironomini and Tanytarsini at the second order sites. SFPE was more efficient at detecting both genera and species at two third-order sites. The differential efficiencies of the two methods are concluded to be related to stream order and size, substrate size, flow and water velocity, depth and habitat heterogeneity, and differential ability to discriminate species among pupal exuviae specimens versus larval specimens. Although both approaches are considered necessary for comprehensive biodiversity assessments of Chironomidae, our results suggest that there is an optimal, but different, allocation of sampling effort for detecting Chironomidae across stream orders and at differing spatial and taxonomic scales.Article submitted 13. August 2014, accepted 31. October 2014, published 22. December 2014.

  5. Environmental Sampling, Monitoring and Site Assessment Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Quality Data Asset includes all current and historical data on environmental quality with regard to the presence of radiological contamination of all kinds regulated...

  6. Environmental controls on daytime net community calcification on a Red Sea reef flat

    KAUST Repository

    Bernstein, W. N.

    2016-01-23

    Coral growth and carbonate accumulation form the foundation of the coral reef ecosystem. Changes in environmental conditions due to coastal development, climate change, and ocean acidification may pose a threat to net carbonate production in the near future. Controlled laboratory studies demonstrate that calcification by corals and coralline algae is sensitive to changes in aragonite saturation state (Ωa), as well as temperature, light, and nutrition. Studies also show that the dissolution rate of carbonate substrates is impacted by changes in carbonate chemistry. The sensitivity of coral reefs to these parameters must be confirmed and quantified in the natural environment in order to predict how coral reefs will respond to local and global changes, particularly ocean acidification. We estimated the daytime hourly net community metabolic rates, both net community calcification (NCC) and net community productivity (NCP), at Sheltered Reef, an offshore platform reef in the central Red Sea. Average NCC was 8 ± 3 mmol m−2 h−1 in December 2010 and 11 ± 1 mmol m−2 h−1 in May 2011, and NCP was 21 ± 7 mmol m−2 h−1 in December 2010 and 44 ± 4 mmol m−2 h−1 in May 2011. We also monitored a suite of physical and chemical properties to help relate the rates at Sheltered Reef to published rates from other sites. While previous research shows that short-term field studies investigating the NCC–Ωa relationship have differing results due to confounding factors, it is important to continue estimating NCC in different places, seasons, and years, in order to monitor changes in NCC versus Ω in space and time, and to ultimately resolve a broader understanding of this relationship.

  7. Environmental controls on daytime net community calcification on a Red Sea reef flat

    Science.gov (United States)

    Bernstein, W. N.; Hughen, K. A.; Langdon, C.; McCorkle, D. C.; Lentz, S. J.

    2016-06-01

    Coral growth and carbonate accumulation form the foundation of the coral reef ecosystem. Changes in environmental conditions due to coastal development, climate change, and ocean acidification may pose a threat to net carbonate production in the near future. Controlled laboratory studies demonstrate that calcification by corals and coralline algae is sensitive to changes in aragonite saturation state (Ωa), as well as temperature, light, and nutrition. Studies also show that the dissolution rate of carbonate substrates is impacted by changes in carbonate chemistry. The sensitivity of coral reefs to these parameters must be confirmed and quantified in the natural environment in order to predict how coral reefs will respond to local and global changes, particularly ocean acidification. We estimated the daytime hourly net community metabolic rates, both net community calcification (NCC) and net community productivity (NCP), at Sheltered Reef, an offshore platform reef in the central Red Sea. Average NCC was 8 ± 3 mmol m-2 h-1 in December 2010 and 11 ± 1 mmol m-2 h-1 in May 2011, and NCP was 21 ± 7 mmol m-2 h-1 in December 2010 and 44 ± 4 mmol m-2 h-1 in May 2011. We also monitored a suite of physical and chemical properties to help relate the rates at Sheltered Reef to published rates from other sites. While previous research shows that short-term field studies investigating the NCC-Ωa relationship have differing results due to confounding factors, it is important to continue estimating NCC in different places, seasons, and years, in order to monitor changes in NCC versus Ω in space and time, and to ultimately resolve a broader understanding of this relationship.

  8. Net-phytoplankton communities in the Western Boundary Currents and their environmental correlations

    Science.gov (United States)

    Chen, Yunyan; Sun, Xiaoxia; Zhun, Mingliang

    2017-05-01

    This study investigated net-phytoplankton biomass, species composition, the phytoplankton abundance horizontal distribution, and the correlations between net-phytoplankton communities and mesoscale structure that were derived from the net samples taken from the Western Boundary Currents during summer, 2014. A total of 199 phytoplankton species belonging to 61 genera in four phyla were identified. The dominant species included Climacodium frauenfeldianum, Thalassiothrix longissima, Rhizosolenia styliformis var. styliformis, Pyrocystis noctiluca, Ceratium trichoceros, and Trichodesmium thiebautii. Four phytoplankton communities were divided by cluster analysis and the clusters were mainly associated with the North Equatorial Counter Current (NECC), the North Equatorial Current (NEC), the Subtropical Counter Current (STCC), and the Luzon Current (LC), respectively. The lowest phytoplankton cell abundance and the highest Trichodesmium filament abundance were recorded in the STCC region. The principal component analysis showed that T. thiebautii preferred warm and nutrient poor water. There was also an increase in phytoplankton abundance and biomass near 5°N in the NECC region, where they benefit from upwellings and eddies.

  9. Serving Real-Time Point Observation Data in netCDF using Climate and Forecasting Discrete Sampling Geometry Conventions

    Science.gov (United States)

    Ward-Garrison, C.; May, R.; Davis, E.; Arms, S. C.

    2016-12-01

    NetCDF is a set of software libraries and self-describing, machine-independent data formats that support the creation, access, and sharing of array-oriented scientific data. The Climate and Forecasting (CF) metadata conventions for netCDF foster the ability to work with netCDF files in general and useful ways. These conventions include metadata attributes for physical units, standard names, and spatial coordinate systems. While these conventions have been successful in easing the use of working with netCDF-formatted output from climate and forecast models, their use for point-based observation data has been less so. Unidata has prototyped using the discrete sampling geometry (DSG) CF conventions to serve, using the THREDDS Data Server, the real-time point observation data flowing across the Internet Data Distribution (IDD). These data originate in text format reports for individual stations (e.g. METAR surface data or TEMP upper air data) and are converted and stored in netCDF files in real-time. This work discusses the experiences and challenges of using the current CF DSG conventions for storing such real-time data. We also test how parts of netCDF's extended data model can address these challenges, in order to inform decisions for a future version of CF (CF 2.0) that would take advantage of features of the netCDF enhanced data model.

  10. Net environmental benefit: introducing a new LCA approach on wastewater treatment systems.

    Science.gov (United States)

    Godin, D; Bouchard, C; Vanrolleghem, P A

    2012-01-01

    Life cycle assessment (LCA) allows evaluating the potential environmental impacts of a product or a service in relation to its function and over its life cycle. In past LCAs applied to wastewater treatment plants (WWTPs), the system function definition has received little attention despite its great importance. This has led to some limitations in LCA results interpretation. A new methodology to perform LCA on WWTPs is proposed to avoid those limitations. It is based on net environmental benefit (NEB) evaluation and requires assessing the potential impact of releasing wastewater without and with treatment besides assessing the impact of the WWTP's life cycle. The NEB allows showing the environmental trade-offs between avoided impact due to wastewater treatment and induced impact by the WWTP's life cycle. NEB is compared with a standard LCA through the case study of a small municipal WWTP consisting of facultative aerated lagoons. The NEB and standard LCA show similar results for impact categories solely related to the WWTP's life cycle but differ in categories where wastewater treatment environmental benefit is accounted for as NEB considers influent wastewater quality whereas standard LCA does not.

  11. The use of narrative sampling in the assessment of social cognition: the Narrative of Emotions Task (NET).

    Science.gov (United States)

    Buck, Benjamin; Ludwig, Kelsey; Meyer, Piper S; Penn, David L

    2014-07-30

    Social cognitive deficits in schizophrenia are well documented and related to functional outcome. Current social cognition measures are often not psychometrically validated, too heterogeneous for standardization, and focus principally on one domain of social cognition rather than the simultaneous activation of multiple domains. Also, few if any allow for personalization of stimuli and interpretation of personally evocative events. An alternative methodology that addresses these limitations is the analysis of samples of personal narratives. The present study evaluates the psychometric properties of a measure called the Narrative of Emotions Task (NET). The NET was used to assess the performance of participants with a diagnosis of schizophrenia or schizoaffective disorder and nonclinical controls. Use of the NET revealed significant impairments in the emotional narratives of participants with schizophrenia. Various NET indices were significantly related to current measures of theory of mind and emotion perception, as well as a social skills role-play, but were not related to measures of attributional style or clinician-rated functioning scales. Overall, the NET׳s psychometric properties justify further use of the narrative sampling method of social cognition assessment in this population. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. Fundamentals of environmental sampling and analysis

    National Research Council Canada - National Science Library

    Zhang, Chunlong Carl

    2007-01-01

    ... and Quantitation Limit 17 Standard Calibration Curve 18 14 16 2.2 Essential Environmental Statistics 20 2.2.1 2.2.2 2.2.3 Measurements of Central Tendency and Dispersion Understanding Probability...

  13. The geographic diversity of nontuberculous mycobacteria isolated from pulmonary samples: an NTM-NET collaborative study

    NARCIS (Netherlands)

    Hoefsloot, W.; Ingen, J. van; Andrejak, C.; Angeby, K.; Bauriaud, R.; Bemer, P.; Beylis, N.; Boeree, M.J.; Cacho, J.; Chihota, V.; Chimara, E.; Churchyard, G.; Cias, R.; Daza, R.; Daley, C.L.; Dekhuijzen, P.N.R.; Domingo, D.; Drobniewski, F.; Esteban, J. De; Fauville-Dufaux, M.; Folkvardsen, D.B.; Gibbons, N.; Gomez-Mampaso, E.; Gonzalez, R.; Hoffmann, H.; Hsueh, P.R.; Indra, A.; Jagielski, T.; Jamieson, F.; Jankovic, M.; Jong, Eefje de; Keane, J.; Koh, W.J.; Lange, B. de; Leao, S.; Macedo, R.; Mannsaker, T.; Marras, T.K.; Maugein, J.; Milburn, H.J.; Mlinko, T.; Morcillo, N.; Morimoto, K.; Papaventsis, D.; Palenque, E.; Paez-Pena, M.; Piersimoni, C.; Polanova, M.; Rastogi, N.; Richter, E.; Ruiz-Serrano, M.J.; Silva, A.; Silva, M.P. da; Simsek, H.; Soolingen, D. van; Szabo, N.; Thomson, R.; Fernandez, T. Tortola; Tortoli, E.; Totten, S.E.; Tyrrell, G.; Vasankari, T.; Villar, M.; Walkiewicz, R.; Winthrop, K.L.; Wagner, D.; Trials, G. Nontuberculous

    2013-01-01

    A significant knowledge gap exists concerning the geographical distribution of nontuberculous mycobacteria (NTM) isolation worldwide. To provide a snapshot of NTM species distribution, global partners in the NTM-Network European Trials Group (NET) framework (www.ntm-net.org), a branch of the

  14. ENVIRONMENTAL SAMPLING AND ANALYSIS IN THE AFTERMATH OF HURRICANE KATRINA

    Science.gov (United States)

    This presentation describes the environmental sampling completed by EPA in southeastern Louisiana after Hurricane Katrina caused major catastrophic damage. Presentation also describes EPA's Environmental Unit activities in Baton Rouge and New Orleans, LA, and Dallas, TX.

  15. Radiation Target Area Sample Environmental Chamber (RTASEC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Payload Systems Inc. proposes the Radiation Target Area Sample Environmental Chamber (RTASEC) as an innovative approach enabling radiobiologists to investigate the...

  16. Optimization of sample patterns for universal kriging of environmental variables

    NARCIS (Netherlands)

    Brus, D.J.; Heuvelink, G.B.M.

    2007-01-01

    The quality of maps obtained by interpolation of observations of a target environmental variable at a restricted number of locations, is partly determined by the spatial pattern of the sample locations. A method is presented for optimization of the sample pattern when the environmental variable is

  17. DOE methods for evaluating environmental and waste management samples.

    Energy Technology Data Exchange (ETDEWEB)

    Goheen, S C; McCulloch, M; Thomas, B L; Riley, R G; Sklarew, D S; Mong, G M; Fadeff, S K [eds.; Pacific Northwest Lab., Richland, WA (United States)

    1994-04-01

    DOE Methods for Evaluating Environmental and Waste Management Samples (DOE Methods) provides applicable methods in use by. the US Department of Energy (DOE) laboratories for sampling and analyzing constituents of waste and environmental samples. The development of DOE Methods is supported by the Laboratory Management Division (LMD) of the DOE. This document contains chapters and methods that are proposed for use in evaluating components of DOE environmental and waste management samples. DOE Methods is a resource intended to support sampling and analytical activities that will aid in defining the type and breadth of contamination and thus determine the extent of environmental restoration or waste management actions needed, as defined by the DOE, the US Environmental Protection Agency (EPA), or others.

  18. Organically bound tritium analysis in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Baglan, N. [CEA/DAM/DIF, Arpajon (France); Kim, S.B. [AECL, Chalk River Laboratories, Chalk River, ON (Canada); Cossonnet, C. [IRSN/PRP-ENV/STEME/LMRE, Orsay (France); Croudace, I.W.; Warwick, P.E. [GAU-Radioanalytical, University of Southampton, Southampton (United Kingdom); Fournier, M. [IRSN/DG/DMQ, Fontenay-aux-Roses (France); Galeriu, D. [IFIN-HH, Horia-Hulubei, Inst. Phys. and Nucl. Eng., Bucharest (Romania); Momoshima, N. [Kyushu University, Radioisotope Ctr., Fukuoka (Japan); Ansoborlo, E. [CEA/DEN/DRCP/CETAMA, Bagnols-sur-Ceze (France)

    2015-03-15

    Organically bound tritium (OBT) has become of increased interest within the last decade, with a focus on its behaviour and also its analysis, which are important to assess tritium distribution in the environment. In contrast, there are no certified reference materials and no standard analytical method through the international organization related to OBT. In order to resolve this issue, an OBT international working group was created in May 2012. Over 20 labs from around the world participated and submitted their results for the first intercomparison exercise results on potato (Sep 2013). The samples, specially-prepared potatoes, were provided in March 2013 to each participant. Technical information and results from this first exercise are discussed here for all the labs which have realised the five replicates necessary to allow a reliable statistical treatment. The results are encouraging as the increased number of participating labs did not degrade the observed dispersion of the results for a similar activity level. Therefore, the results do not seem to depend on the analytical procedure used. From this work an optimised procedure can start to be developed to deal with OBT analysis and will guide subsequent planned OBT trials by the international group.

  19. Applications of Liquid-Phase Microextraction in the Sample Preparation of Environmental Solid Samples

    Directory of Open Access Journals (Sweden)

    Helena Prosen

    2014-05-01

    Full Text Available Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc. published in the last decade. Several innovative liquid-phase microextraction (LPME techniques that have emerged recently have also been applied as an aid in sample preparation of these samples: single-drop microextraction (SDME, hollow fiber-liquid phase microextraction (HF-LPME, dispersive liquid-liquid microextraction (DLLME. Besides the common organic solvents, surfactants and ionic liquids are also used. However, these techniques have to be combined with another technique to release the analytes from the solid sample into an aqueous solution. In the present review, the published methods were categorized into three groups: LPME in combination with a conventional solvent extraction; LPME in combination with an environmentally friendly extraction; LPME without previous extraction. The applicability of these approaches to the sample preparation for the determination of pollutants in solid environmental samples is discussed, with emphasis on their strengths, weak points and environmental impact.

  20. Panel 3: conducting environmental surveillance sampling to identify exposures.

    Science.gov (United States)

    Batts, Robert; Parzik, Diana

    2011-07-01

    Environmental sampling technology has improved significantly since Operations Desert Shield and Storm (Gulf War I, August 6, 1990-February 27, 1991). Deployment of U.S. Forces overseas and Joint Service operations have increased, and large numbers of troops are currently deployed for long periods of time. Concerns of adverse health effects from environmental exposures, similar to the concerns about exposures to oil well fires in Gulf War I, continue to occur today. Although progress has been made in developing Joint Service policies for training and conducting environmental sampling, the military doctrine that drives this training and allows for the purchase of updated sampling equipment has been slow to respond to changes, thus resulting in conflicts between current technology and assets available in the field. The military needs to remain flexible to new technology and new requirements, and must standardize doctrine and training across the services, and acquire standardized, state-of-the-art sampling equipment to improve field assets.

  1. Radiological analyses of Marshall Islands environmental samples, 1974--1976

    Energy Technology Data Exchange (ETDEWEB)

    Greenhouse, N.A.; Miltenberger, R.P.; Cua, F.T.

    1977-12-12

    Results are reported from the radiological analysis of environmental samples collected in the Marshall Islands during 1974 through 1976. Most of the samples were collected on or near the Bikini Atoll and included plants, soil, fish, catchment water, and sediments, with emphasis on local marine and terrestrial food items. Data are presented from ..gamma.. spectral analysis and the content of /sup 90/Sr and transuranic elements in the samples.

  2. Detection of the actinides and cesium from environmental samples

    Science.gov (United States)

    Snow, Mathew Spencer

    Detection of the actinides and cesium in the environment is important for a variety of applications ranging from environmental remediation to safeguards and nuclear forensics. The utilization of multiple different elemental concentrations and isotopic ratios together can significantly improve the ability to attribute contamination to a unique source term and/or generation process; however, the utilization of multiple elemental "signatures" together from environmental samples requires knowledge of the impact of chemical fractionation for various elements under a variety of environmental conditions (including predominantly aqueous versus arid conditions). The research reported in this dissertation focuses on three major areas: 1. Improving the understanding of actinide-mineral interactions at ultra-low concentrations. Chapter 2 reports a batch sorption and modeling study of Np(V) sorption to the mineral goethite from attomolar to micromolar concentrations. 2. Improving the detection capabilities for Thermal Ionization Mass Spectrometry (TIMS) analyses of ultra-trace cesium from environmental samples. Chapter 4 reports a new method which significantly improves the chemical yields, purification, sample processing time, and ultimately, the detection limits for TIMS analyses of femtogram quantities of cesium from a variety of environmental sample matrices. 3. Demonstrating how actinide and cesium concentrations and isotopic ratios from environmental samples can be utilized together to determine a wealth of information including environmental transport mechanisms (e.g. aqueous versus arid transport) and information on the processes which generated the original material. Chapters1, 3 and 5 demonstrate these principles using Pu, Am, Np, and Cs concentrations and isotopic ratios from contaminated soils taken near the Subsurface Disposal Area (SDA) of Idaho National Laboratory (INL) (a low level radioactive waste disposal site in southeastern Idaho).

  3. A protocol for collecting environmental DNA samples from streams

    Science.gov (United States)

    Kellie J. Carim; Kevin S. McKelvey; Michael K. Young; Taylor M. Wilcox; Michael K. Schwartz

    2016-01-01

    Environmental DNA (eDNA) is DNA that has been released by an organism into its environment, such that the DNA can be found in air, water, or soil. In aquatic systems, eDNA has been shown to provide a sampling approach that is more sensitive for detecting target organisms faster, and less expensively than previous approaches. However, eDNA needs to be sampled in a...

  4. Environmental sampling for Salmonella spp. in Colorado animal shelters.

    Science.gov (United States)

    Steneroden, K K; Hill, A E; Salman, M D

    2011-09-01

    Salmonella enterica is an important zoonotic agent and nosocomial infections and epidemics have occurred in animal facilities. The objective of this study was to estimate the prevalence of Salmonella in the environment in animal shelters. From 12 to 25 samples were taken from each shelter to represent environmental contamination. Samples were collected from surfaces in areas used by animals and in public access areas including animal receiving rooms, kennels, paediatric wards, treatment, visitation rooms, isolation, euthanasia, outdoor runs and play areas, reception rooms, animal transport vehicles, offices, break rooms and restrooms. Samples were tested for Salmonella and compared within shelters to identify high- and low-risk areas; and between shelters to identify differences in environmental contamination by geographical location, infection control policies, and shelter size characteristics. Twenty-eight per cent of sampled Colorado shelters had environmental Salmonella contamination. Two regions in the eastern 1/3 of the state had prevalences of 30% and 100%. Within-shelter sample prevalence ranged from 0 to 100%. Results of this study indicate that animal shelters can be frequently contaminated with Salmonella spp., a variety of Salmonella species may be present, contamination can be widespread within a facility and recovered isolates may harbour antibiotic resistance The findings from this study may influence and help focus educational policy on issues of infection control and zoonotic disease awareness in animal shelters. © 2010 Blackwell Verlag GmbH.

  5. The determination of total tin and organotin compounds in environmental samples

    National Research Council Canada - National Science Library

    Waldock, M.J; Waite, M.E; Miller, D; Smith, D.J; Law, R.J

    1989-01-01

    .... Environmental damage has been demonstrated to occur when tributyltin compounds are used in antifouling formulations on large numbers of boats in enclosed waters, on antifouled nets used to contain...

  6. DOE methods for evaluating environmental and waste management samples

    Energy Technology Data Exchange (ETDEWEB)

    Goheen, S.C.; McCulloch, M.; Thomas, B.L.; Riley, R.G.; Sklarew, D.S.; Mong, G.M.; Fadeff, S.K. [eds.

    1994-10-01

    DOE Methods for Evaluating Environmental and Waste Management Samples (DOE Methods) is a resource intended to support sampling and analytical activities for the evaluation of environmental and waste management samples from U.S. Department of Energy (DOE) sites. DOE Methods is the result of extensive cooperation from all DOE analytical laboratories. All of these laboratories have contributed key information and provided technical reviews as well as significant moral support leading to the success of this document. DOE Methods is designed to encompass methods for collecting representative samples and for determining the radioisotope activity and organic and inorganic composition of a sample. These determinations will aid in defining the type and breadth of contamination and thus determine the extent of environmental restoration or waste management actions needed, as defined by the DOE, the U.S. Environmental Protection Agency, or others. The development of DOE Methods is supported by the Analytical Services Division of DOE. Unique methods or methods consolidated from similar procedures in the DOE Procedures Database are selected for potential inclusion in this document. Initial selection is based largely on DOE needs and procedure applicability and completeness. Methods appearing in this document are one of two types, {open_quotes}Draft{close_quotes} or {open_quotes}Verified{close_quotes}. {open_quotes}Draft{close_quotes} methods that have been reviewed internally and show potential for eventual verification are included in this document, but they have not been reviewed externally, and their precision and bias may not be known. {open_quotes}Verified{close_quotes} methods in DOE Methods have been reviewed by volunteers from various DOE sites and private corporations. These methods have delineated measures of precision and accuracy.

  7. Expected net present value of sample information: from burden to investment.

    Science.gov (United States)

    Hall, Peter S; Edlin, Richard; Kharroubi, Samer; Gregory, Walter; McCabe, Christopher

    2012-01-01

    The Expected Value of Information Framework has been proposed as a method for identifying when health care technologies should be immediately reimbursed and when any reimbursement should be withheld while awaiting more evidence. This framework assesses the value of obtaining additional evidence to inform a current reimbursement decision. This represents the burden of not having the additional evidence at the time of the decision. However, when deciding whether to reimburse now or await more evidence, decision makers need to know the value of investing in more research to inform a future decision. Assessing this value requires consideration of research costs, research time, and what happens to patients while the research is undertaken and after completion. The investigators describe a development of the calculation of the expected value of sample information that assesses the value of investing in further research, including an only-in-research strategy and an only-with-research strategy.

  8. Partitioning net ecosystem carbon exchange into net assimilation and respiration using 13CO2 measurements: A cost-effective sampling strategy

    Science.gov (United States)

    OgéE, J.; Peylin, P.; Ciais, P.; Bariac, T.; Brunet, Y.; Berbigier, P.; Roche, C.; Richard, P.; Bardoux, G.; Bonnefond, J.-M.

    2003-06-01

    The current emphasis on global climate studies has led the scientific community to set up a number of sites for measuring the long-term biosphere-atmosphere net CO2 exchange (net ecosystem exchange, NEE). Partitioning this flux into its elementary components, net assimilation (FA), and respiration (FR), remains necessary in order to get a better understanding of biosphere functioning and design better surface exchange models. Noting that FR and FA have different isotopic signatures, we evaluate the potential of isotopic 13CO2 measurements in the air (combined with CO2 flux and concentration measurements) to partition NEE into FR and FA on a routine basis. The study is conducted at a temperate coniferous forest where intensive isotopic measurements in air, soil, and biomass were performed in summer 1997. The multilayer soil-vegetation-atmosphere transfer model MuSICA is adapted to compute 13CO2 flux and concentration profiles. Using MuSICA as a "perfect" simulator and taking advantage of the very dense spatiotemporal resolution of the isotopic data set (341 flasks over a 24-hour period) enable us to test each hypothesis and estimate the performance of the method. The partitioning works better in midafternoon when isotopic disequilibrium is strong. With only 15 flasks, i.e., two 13CO2 nighttime profiles (to estimate the isotopic signature of FR) and five daytime measurements (to perform the partitioning) we get mean daily estimates of FR and FA that agree with the model within 15-20%. However, knowledge of the mesophyll conductance seems crucial and may be a limitation to the method.

  9. Environmental evidence for net methane production and oxidation in putative ANaerobic MEthanotrophic (ANME) archaea

    DEFF Research Database (Denmark)

    Lloyd, Karen; Teske, Andreas; Alperin, Marc J.

    2011-01-01

    Uncultured ANaerobic MEthanotrophic (ANME) archaea are often assumed to be obligate methanotrophs that are incapable of net methanogenesis, and are therefore used as proxies for anaerobic methane oxidation in many environments in spite of uncertainty regarding their metabolic capabilities...... versus methane production in sediments from the White Oak River estuary, North Carolina. ANME-1 consistently transcribe 16S rRNA and mRNA of methyl coenzyme M reductase (mcrA), the key gene for methanogenesis, up to 45 cm into methanogenic sediments. CARD-FISH shows that ANME-1 exist as single rod....... These results, along with a re-assessment of the published Iiterature, change the perspective to ANME-1 as methanogens that are also capable of methane oxidation....

  10. Modified electrode voltammetric sensors for trace metals in environmental samples

    Directory of Open Access Journals (Sweden)

    Brett Christopher M.A.

    2000-01-01

    Full Text Available Nafion-modified mercury thin film electrodes have been investigated for the analysis of trace metals in environmental samples of waters and effluent by batch injection analysis with square wave anodic stripping voltammetry. The method, involving injection over the detector electrode of untreated samples of volume of the order of 50 microlitres has fast response, blocking and fouling of the electrode is minimum as shown by studies with surface-active components. Comparison is made between glassy carbon substrate electrodes and carbon fibre microelectrode array substrates, the latter leading to a small sensitivity enhancement. Application to analysis of river water and industrial effluent for labile zinc, cadmium, lead and copper ions is demonstrated in collected samples and after acid digestion.

  11. Cost-effective sampling of ¹³⁷Cs-derived net soil redistribution: part 1--estimating the spatial mean across scales of variation.

    Science.gov (United States)

    Li, Y; Chappell, A; Nyamdavaa, B; Yu, H; Davaasuren, D; Zoljargal, K

    2015-03-01

    The (137)Cs technique for estimating net time-integrated soil redistribution is valuable for understanding the factors controlling soil redistribution by all processes. The literature on this technique is dominated by studies of individual fields and describes its typically time-consuming nature. We contend that the community making these studies has inappropriately assumed that many (137)Cs measurements are required and hence estimates of net soil redistribution can only be made at the field scale. Here, we support future studies of (137)Cs-derived net soil redistribution to apply their often limited resources across scales of variation (field, catchment, region etc.) without compromising the quality of the estimates at any scale. We describe a hybrid, design-based and model-based, stratified random sampling design with composites to estimate the sampling variance and a cost model for fieldwork and laboratory measurements. Geostatistical mapping of net (1954-2012) soil redistribution as a case study on the Chinese Loess Plateau is compared with estimates for several other sampling designs popular in the literature. We demonstrate the cost-effectiveness of the hybrid design for spatial estimation of net soil redistribution. To demonstrate the limitations of current sampling approaches to cut across scales of variation, we extrapolate our estimate of net soil redistribution across the region, show that for the same resources, estimates from many fields could have been provided and would elucidate the cause of differences within and between regional estimates. We recommend that future studies evaluate carefully the sampling design to consider the opportunity to investigate (137)Cs-derived net soil redistribution across scales of variation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Macrozooplankton rather than Calanus are responsible for autumn DVM in Arctic fjords and pack ice: Backscatter contribution by net samples compared with acoustics

    DEFF Research Database (Denmark)

    Berge, J.; Cottier, F.; Varpe, Øystein

    2011-01-01

    times of the year. Herein we report on an autumn sampling campaign at four different locations around Svalbard using a combination of net sampling and 36 hr mooring deployments with 300kHz ADCPs. DVM patterns were strong but differed among the locations in terms of both backscatter strength...

  13. Molecular Identification of Gambierdiscus and Fukuyoa (Dinophyceae from Environmental Samples

    Directory of Open Access Journals (Sweden)

    Kirsty F. Smith

    2017-08-01

    Full Text Available Ciguatera Fish Poisoning (CFP is increasing across the Pacific and the distribution of the causative dinoflagellates appears to be expanding. Subtle differences in thecal plate morphology are used to distinguish dinoflagellate species, which are difficult to determine using light microscopy. For these reasons we sought to develop a Quantitative PCR assay that would detect all species from both Gambierdiscus and Fukuyoa genera in order to rapidly screen environmental samples for potentially toxic species. Additionally, a specific assay for F. paulensis was developed as this species is of concern in New Zealand coastal waters. Using the assays we analyzed 31 samples from three locations around New Zealand and the Kingdom of Tonga. Fourteen samples in total were positive for Gambierdiscus/Fukuyoa and two samples were also positive using the F. paulensis assay. Samples from the Kermadec Islands were further characterized using high-throughput sequencing metabarcoding. The majority of reads corresponded to Gambierdiscus species with three species identified at all sites (G. australes, G. honu and G. polynesiensis. This is the first confirmed identification of G. polynesiensis, a known ciguatoxin producer, in New Zealand waters. Other known toxin-producing genera were also detected, included Alexandrium, Amphidinium, Azadinium, Dinophysis, Ostreopsis, and Prorocentrum.

  14. Rapid extraction and assay of uranium from environmental surface samples

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, Christopher A.; Chouyyok, Wilaiwan; Speakman, Robert J.; Olsen, Khris B.; Addleman, Raymond Shane

    2017-10-01

    Extraction methods enabling faster removal and concentration of uranium compounds for improved trace and low-level assay are demonstrated for standard surface sampling material in support of nuclear safeguards efforts, health monitoring, and other nuclear analysis applications. A key problem with the existing surface sampling swipes is the requirement for complete digestion of sample and sampling matrix. This is a time-consuming and labour-intensive process that limits laboratory throughput, elevates costs, and increases background levels. Various extraction methods are explored for their potential to quickly and efficiently remove different chemical forms of uranium from standard surface sampling material. A combination of carbonate and peroxide solutions is shown to give the most rapid and complete form of uranyl compound extraction and dissolution. This rapid extraction process is demonstrated to be compatible with standard inductive coupled plasma mass spectrometry methods for uranium isotopic assay as well as screening techniques such as x-ray fluorescence. The general approach described has application beyond uranium to other analytes of nuclear forensic interest (e.g., rare earth elements and plutonium) as well as heavy metals for environmental and industrial hygiene monitoring.

  15. [Effects of environmental factors on catch variation of main species of stow net fisheries in East China Sea].

    Science.gov (United States)

    Zhou, Sufang; Fan, Wei; Cui, Xuesen; Cheng, Yanhong

    2004-09-01

    Stow net fishery is one of the important fishing methods in the East China Sea. This paper used the generalized additive models (GAMs) to quantitatively describe the relationships between stow net catch and environmental factors (sea surface temperature SST, water depth, fishing position and tide) in the East China Sea. The results indicated that each factor had its own nonlinear effect on the catch per unit effort (CPUE) of haitail (Trichiurus japonicus), small yellow croaker (Larimichthys polyactis) and butter fish (Pampus spp.), and SST and water depth were the key factors. The GAMs' fitting results showed that SST had the strongest effect on the catch per unit effort of haitail, and water depth had the second one. The effects of fishing location and tide were very small. Water depth was the most influential variable when adjusted for the effects on small yellow croaker. SST, fishing location and tide had similar effects. Meanwhile, water depth and SST were the key factors affecting the catch per unit effort of butter fish. They had similar intensity.

  16. Intercomparison of radionuclides in environmental samples 2000-2001

    Energy Technology Data Exchange (ETDEWEB)

    Fogh, C.L.; Nielsen, S.P.; Keith-Roach, M.J. [Risoe National Lab., Roskilde (Denmark)

    2002-07-01

    An intercomparison exercise on radionuclides in environmental samples was carried out during 2000-2001 as part of a Nordic NKS project. The exercise included six sample types (aerosols, dry milk, soil, seawater, seaweed and lake water) and a range of man-made and naturally occurring radionuclides, mainly gamma-emitters but also beta- and alpha-emitters. A total of 25 Nordic and Baltic laboratories participated. The analytical quality across participants was generally good with about two thirds of the results in close agreement with estimated mean values. The exercise has demonstrated improved agreement between the results and more realistic analytical uncertainties submitted by the participants compared with a previous exercise carried out during 1998-1999 in the same NKS project. (au)

  17. An Environmentally Friendly, Cost-Effective Determination of Lead in Environmental Samples Using Anodic Stripping Voltammetry

    Science.gov (United States)

    Goldcamp, Michael J.; Underwood, Melinda N.; Cloud, Joshua L.; Harshman, Sean

    2008-01-01

    Contamination of the environment with heavy metals such as lead presents many health risks. Simple, effective, and field-portable methods for the measurement of toxic metals in environmental samples are vital tools for evaluating the risks that these contaminants pose. This article describes the use of new developments in anodic stripping…

  18. Identification and characterization of nuclease activities in anaerobic environmental samples.

    Science.gov (United States)

    Ruiz, T R; Andrews, S; Smith, G B

    2000-08-01

    DNA-degrading activity from anaerobic samples of bovine ruminal fluid, primary anaerobic digestor wastewater, freshwater sediments, and marine sediments was observed in the presence of 5 mM EDTA. Nuclease activity experiments involved exposing salmon chromosomal DNA to the environmental samples in 50 mM pH 7.2 buffer, incubating at 37 degrees C, and subjecting the products to electrophoresis. The same stock and concentration of EDTA used in these assays (5 mM) completely inhibited commercial grade DNase. Nuclease activity in two of the samples, ruminal fluid and wastewater, was further characterized. DNA degradation in the ruminal sample was significantly reduced when EDTA or citrate concentrations were increased to 50 mM or above. DNA degradation activity in ruminal fluid was associated with material that passed through a 0.22-micron filter, but wastewater activity was associated with material retained by a 3-micron filter. Degradation activity in the wastewater was resistant to heat pretreatment, whereas the rumen activity was heat-labile (70 degrees C, 60 min). These results demonstrated the biochemical complexity of these two environments and that high molecular weight DNA has a short half-life in these anaerobic environments.

  19. Comparison of DNA preservation methods for environmental bacterial community samples

    Science.gov (United States)

    Gray, Michael A.; Pratte, Zoe A.; Kellogg, Christina A.

    2013-01-01

    Field collections of environmental samples, for example corals, for molecular microbial analyses present distinct challenges. The lack of laboratory facilities in remote locations is common, and preservation of microbial community DNA for later study is critical. A particular challenge is keeping samples frozen in transit. Five nucleic acid preservation methods that do not require cold storage were compared for effectiveness over time and ease of use. Mixed microbial communities of known composition were created and preserved by DNAgard™, RNAlater®, DMSO–EDTA–salt (DESS), FTA® cards, and FTA Elute® cards. Automated ribosomal intergenic spacer analysis and clone libraries were used to detect specific changes in the faux communities over weeks and months of storage. A previously known bias in FTA® cards that results in lower recovery of pure cultures of Gram-positive bacteria was also detected in mixed community samples. There appears to be a uniform bias across all five preservation methods against microorganisms with high G + C DNA. Overall, the liquid-based preservatives (DNAgard™, RNAlater®, and DESS) outperformed the card-based methods. No single liquid method clearly outperformed the others, leaving method choice to be based on experimental design, field facilities, shipping constraints, and allowable cost.

  20. New quantitative detection of pathogens in heterogeneous environmental samples

    Science.gov (United States)

    Lee, Eun-Hee; Wang, Xiaofang; Mitchell, Kristi; Chae, Seon-Ha; Son, Ahjeong

    2015-04-01

    Quantum dots and magnetic beads based genomic assay (NanoGene assay) has been developed for sensitive and inhibition resistant gene quantification to achieve in-situ bacteria monitoring in environmental samples. In this study, eaeA gene of pathogenic E. coli O157:H7 was quantified. The result demonstrated the excellent sensitivity (i.e., limit of detection: 87 gene copies for dsDNA and 890 zeptomolar for ssDNA) in the presence of nonspecific microbial populations (Kim et al., 2010; 2011a). The feasibility of the developed gene quantification for non-laboratory environment usage (in-situ use) was investigated. Therefore, DNA hybridization was achieved at ambient temperature and minimum agitation, and the analysis was completed within hours. Most importantly, the NanoGene assay demonstrated the resistance to the presence of naturally occurring inhibitors (humic acids, cations) and residual reagents (surfactants, alcohols) from DNA extraction (Kim et al., 2011b). The assay was also applied to humic acids laden soils (7 types of soils with various amount of organic matters) and successfully quantified 105 to 108 CFU of E. coli O157:H7 per gram soil (R2 = 0.99). The results indicate that the presented NanoGene assay is suitable for further development as an in-situ bacteria monitoring method for working with heterogeneous environmental samples (Wang et al., 2013). Another aspect of the method is to transform the NanoGene assay into a portable device that can be used as a pathogenic bacteria detector in environment. The project consisted of the first inline fluidic components development and characterization as well as the first integration effort on a briefcase platform for the in-situ pathogen detection system (IPDS) (Mitchell et al., 2014). Our long term vision is to further miniaturize the briefcase platform implementation of the IPDS and to commercialize the handheld version of the IPDS.

  1. Looking through a dirty glass: how different can the characterization of a fish fauna be when distinct nets are used for sampling?

    Directory of Open Access Journals (Sweden)

    Gianfranco Ceni

    2013-10-01

    Full Text Available The present study compares fish species composition, dominance, and size-structure patterns at an open sand beach area (32°15'S, 52°46'W in Mirim Lake, RS, Brazil, estimated from samples collected with two distinct beach seine nets. The BS-9m net is 9 m long and 1.5 m high, and is made with a 5 mm multifilament mesh on its central portion and 12 mm on the side wings. The BS-30m net is 30 m long and 1.8 m high, with a 12 mm monofilament nylon mesh all over the net, except for a 30 cm strip made with a 12 mm multifilament mesh on the lower portion. Thirty hauls were performed with both nets resulting in a total of 849 fish captured, comprising 34 species. BS-9m was selective for individuals smaller than 60 mm TL and BS-30m for individuals larger than 60 mm TL. Low values of the faunal similarity (JI = 0.41, ANOSIM R = 0.2309, p < 0.0001 and numeric dominance (PSI = 0.46 indexes were revealed. We suggest that the concurrent use of both samplers provide a better description of the fish fauna of shallow areas. However, due to their robustness, rusticity, and ease of use and maintenance, small multifilament seines are indicated for regular work in environments without obstacles and with little open sand area available for sampling.

  2. [DOE method for evaluating environmental and waste management samples: Revision 1, Addendum 1

    Energy Technology Data Exchange (ETDEWEB)

    Goheen, S.C.

    1995-04-01

    The US Dapartment of Energy`s (DOE`s) environmental and waste management (EM) sampling and analysis activities require that large numbers of samples be analyzed for materials characterization, environmental surveillance, and site-remediation programs. The present document, DOE Methods for Evaluating Environmental and Waste Management Samples (DOE Methods), is a supplemental resource for analyzing many of these samples.

  3. RadNet-Air Near Real Time Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — RadNet-Air is a national network of air monitoring stations that regularly collect air samples for near real time analysis of radioactivity. The data is transmitted...

  4. Environmental Assessment of Natural Radioactivity in Soil Samples

    Directory of Open Access Journals (Sweden)

    Ryuta Hazama

    2009-07-01

    Full Text Available The environmental impacts and hazards due to the unstoppable hot mud flow by the East Java ‘LUSI’ Mud Volcano are increasing since its unexpected eruption on May 29, 2006. Analysis should be undertaken, not only to examine its impact on human health and the environment, but also to explore the potential benefits of the mud flow. One may be able to tap the mud flow as a material source for brick and cement. Recently there has been great concern about the health risks associated with exposure to natural radioactivity present in soil and building materials all over the world. In this context, measurements for natural radioactive isotopes such as 238U and 232Th series, and 40K in mud samples were carried out using the HPGe (High-Purity Germanium detector to determine the re-usability of the mud. 226Ra, 232Th and 40K activity concentrations were found to be 13±1, 15±1 and 111±3 Bq/kg (1 Bq = 1 sec-1, respectively, and the corresponding activity index was found to be 0.16±0.02. These values were compared with previous data and our measured accuracy was improved by a factor of nine at the maximum. Radium equivalent activity, external and internal hazard indices, and annual effective dose equivalent were also evaluated and all were found to be within acceptable limits.

  5. Methods to maximise recovery of environmental DNA from water samples.

    Directory of Open Access Journals (Sweden)

    Rheyda Hinlo

    Full Text Available The environmental DNA (eDNA method is a detection technique that is rapidly gaining credibility as a sensitive tool useful in the surveillance and monitoring of invasive and threatened species. Because eDNA analysis often deals with small quantities of short and degraded DNA fragments, methods that maximize eDNA recovery are required to increase detectability. In this study, we performed experiments at different stages of the eDNA analysis to show which combinations of methods give the best recovery rate for eDNA. Using Oriental weatherloach (Misgurnus anguillicaudatus as a study species, we show that various combinations of DNA capture, preservation and extraction methods can significantly affect DNA yield. Filtration using cellulose nitrate filter paper preserved in ethanol or stored in a -20°C freezer and extracted with the Qiagen DNeasy kit outperformed other combinations in terms of cost and efficiency of DNA recovery. Our results support the recommendation to filter water samples within 24hours but if this is not possible, our results suggest that refrigeration may be a better option than freezing for short-term storage (i.e., 3-5 days. This information is useful in designing eDNA detection of low-density invasive or threatened species, where small variations in DNA recovery can signify the difference between detection success or failure.

  6. Methods to maximise recovery of environmental DNA from water samples.

    Science.gov (United States)

    Hinlo, Rheyda; Gleeson, Dianne; Lintermans, Mark; Furlan, Elise

    2017-01-01

    The environmental DNA (eDNA) method is a detection technique that is rapidly gaining credibility as a sensitive tool useful in the surveillance and monitoring of invasive and threatened species. Because eDNA analysis often deals with small quantities of short and degraded DNA fragments, methods that maximize eDNA recovery are required to increase detectability. In this study, we performed experiments at different stages of the eDNA analysis to show which combinations of methods give the best recovery rate for eDNA. Using Oriental weatherloach (Misgurnus anguillicaudatus) as a study species, we show that various combinations of DNA capture, preservation and extraction methods can significantly affect DNA yield. Filtration using cellulose nitrate filter paper preserved in ethanol or stored in a -20°C freezer and extracted with the Qiagen DNeasy kit outperformed other combinations in terms of cost and efficiency of DNA recovery. Our results support the recommendation to filter water samples within 24hours but if this is not possible, our results suggest that refrigeration may be a better option than freezing for short-term storage (i.e., 3-5 days). This information is useful in designing eDNA detection of low-density invasive or threatened species, where small variations in DNA recovery can signify the difference between detection success or failure.

  7. Environmental Radiation Data (ERD) Journal Report 166

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of April - June 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  8. Environmental Radiation Data (ERD) Journal Report 156

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of October - December 2013. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.

  9. Environmental Radiation Data (ERD) Journal Report 161

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of January - March 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  10. Environmental Radiation Data (ERD) Journal Report 158

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of April - June 2014. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.

  11. Environmental Radiation Data (ERD) Journal Report 157

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of January - March 2014. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.

  12. Environmental Radiation Data (ERD) Journal Report 160

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of October - December 2014. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  13. Environmental Radiation Data (ERD) Journal Report 163

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of July - September 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  14. Environmental Radiation Data (ERD) Journal Report 159

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of July - September 2014. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  15. Environmental Radiation Data (ERD) Journal Report 167

    Science.gov (United States)

    RadNet Environmental Radiation Data (ERD) journal report for the period of July – September 2016. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  16. Environmental Radiation Data (ERD) Journal Report 154

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of April - June 2013. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.

  17. Environmental Radiation Data (ERD) Journal Report 155

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of July - September 2013. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.

  18. Environmental Radiation Data (ERD) Journal Report 162

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of April - June 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  19. Environmental Radiation Data (ERD) Journal Report 165

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of January - March 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  20. Environmental Radiation Data (ERD) Journal Report 164

    Science.gov (United States)

    RadNet environmental radiation monitoring data report for the period of October - December 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  1. Environmental Radiation Data (ERD) Journal Report 168

    Science.gov (United States)

    RadNet Environmental Radiation Data (ERD) journal report for the period of October - December 2016. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.

  2. Detection of Naegleria Species in Environmental Samples from Peninsular Malaysia

    Science.gov (United States)

    Ithoi, Init; Ahmad, Arine Fadzlun; Nissapatorn, Veeranoot; Lau, Yee Ling; Mahmud, Rohela; Mak, Joon Wah

    2011-01-01

    Background In Malaysia, researchers and medical practitioners are unfamiliar with Naegleria infections. Thus little is known about the existence of pathogenic Naegleria fowleri, and the resultant primary amoebic meningoencephalitis (PAM) is seldom included in the differential diagnosis of central nervous system infections. This study was conducted to detect the presence of Naegleria species in various environmental samples. Methods/Findings A total of 41 Naegleria-like isolates were isolated from water and dust samples. All these isolates were subjected to PCR using two primer sets designed from the ITS1-ITS2 regions. The N. fowleri species-specific primer set failed to produce the expected amplicon. The Naegleria genus-specific primers produced amplicons of 408 bp (35), 450 bp (2), 457 bp (2) or 381 bp (2) from all 41 isolates isolated from aquatic (33) and dust (8) samples. Analysis of the sequences from 10 representative isolates revealed that amplicons with fragments 408, 450 and 457 bp showed homology with non-pathogenic Naegleria species, and 381 bp showed homology with Vahlkampfia species. These results concurred with the morphological observation that all 39 isolates which exhibited flagella were Naegleria, while 2 isolates (AC7, JN034055 and AC8, JN034056) that did not exhibit flagella were Vahlkampfia species. Conclusion To date, pathogenic species of N. fowleri have not been isolated from Malaysia. All 39 isolates that produced amplicons (408, 450 and 457 bp) from the genus-specific primers were identified as being similar to nonpathogenic Naegleria. Amplicon 408 bp from 5 representative isolates showed 100% and 99.7% identity to Naegleria philippinensis isolate RJTM (AM167890) and is thus believed to be the most common species in our environment. Amplicons 450 bp and 457 bp were respectively believed to be from 2 new species of Naegleria, since representative isolates showed lower homology and had a longer base pair length when compared to the reference

  3. Detection of Naegleria species in environmental samples from Peninsular Malaysia.

    Directory of Open Access Journals (Sweden)

    Init Ithoi

    Full Text Available BACKGROUND: In Malaysia, researchers and medical practitioners are unfamiliar with Naegleria infections. Thus little is known about the existence of pathogenic Naegleria fowleri, and the resultant primary amoebic meningoencephalitis (PAM is seldom included in the differential diagnosis of central nervous system infections. This study was conducted to detect the presence of Naegleria species in various environmental samples. METHODS/FINDINGS: A total of 41 Naegleria-like isolates were isolated from water and dust samples. All these isolates were subjected to PCR using two primer sets designed from the ITS1-ITS2 regions. The N. fowleri species-specific primer set failed to produce the expected amplicon. The Naegleria genus-specific primers produced amplicons of 408 bp (35, 450 bp (2, 457 bp (2 or 381 bp (2 from all 41 isolates isolated from aquatic (33 and dust (8 samples. Analysis of the sequences from 10 representative isolates revealed that amplicons with fragments 408, 450 and 457 bp showed homology with non-pathogenic Naegleria species, and 381 bp showed homology with Vahlkampfia species. These results concurred with the morphological observation that all 39 isolates which exhibited flagella were Naegleria, while 2 isolates (AC7, JN034055 and AC8, JN034056 that did not exhibit flagella were Vahlkampfia species. CONCLUSION: To date, pathogenic species of N. fowleri have not been isolated from Malaysia. All 39 isolates that produced amplicons (408, 450 and 457 bp from the genus-specific primers were identified as being similar to nonpathogenic Naegleria. Amplicon 408 bp from 5 representative isolates showed 100% and 99.7% identity to Naegleria philippinensis isolate RJTM (AM167890 and is thus believed to be the most common species in our environment. Amplicons 450 bp and 457 bp were respectively believed to be from 2 new species of Naegleria, since representative isolates showed lower homology and had a longer base pair length when compared to

  4. Net Zero Fort Carson: Integrating Energy, Water, and Waste Strategies to Lower the Environmental Impact of a Military Base

    Science.gov (United States)

    Military bases resemble small cities and face similar sustainability challenges. As pilot studies in the U.S. Army Net Zero program, 17 locations are moving to 100% renewable energy, zero depletion of water resources, and/or zero waste to landfill by 2020. Some bases target net z...

  5. Genomic Sequencing of Single Microbial Cells from Environmental Samples

    Energy Technology Data Exchange (ETDEWEB)

    Ishoey, Thomas; Woyke, Tanja; Stepanauskas, Ramunas; Novotny, Mark; Lasken, Roger S.

    2008-02-01

    Recently developed techniques allow genomic DNA sequencing from single microbial cells [Lasken RS: Single-cell genomic sequencing using multiple displacement amplification, Curr Opin Microbiol 2007, 10:510-516]. Here, we focus on research strategies for putting these methods into practice in the laboratory setting. An immediate consequence of single-cell sequencing is that it provides an alternative to culturing organisms as a prerequisite for genomic sequencing. The microgram amounts of DNA required as template are amplified from a single bacterium by a method called multiple displacement amplification (MDA) avoiding the need to grow cells. The ability to sequence DNA from individual cells will likely have an immense impact on microbiology considering the vast numbers of novel organisms, which have been inaccessible unless culture-independent methods could be used. However, special approaches have been necessary to work with amplified DNA. MDA may not recover the entire genome from the single copy present in most bacteria. Also, some sequence rearrangements can occur during the DNA amplification reaction. Over the past two years many research groups have begun to use MDA, and some practical approaches to single-cell sequencing have been developed. We review the consensus that is emerging on optimum methods, reliability of amplified template, and the proper interpretation of 'composite' genomes which result from the necessity of combining data from several single-cell MDA reactions in order to complete the assembly. Preferred laboratory methods are considered on the basis of experience at several large sequencing centers where >70% of genomes are now often recovered from single cells. Methods are reviewed for preparation of bacterial fractions from environmental samples, single-cell isolation, DNA amplification by MDA, and DNA sequencing.

  6. a study of predictors of environmental behaviour using us samples

    African Journals Online (AJOL)

    behaviour predictors (perceived skill and knowledge of environmental action strategies ... intervention (ecomanagement), persuasion, legal action, and political action. A behaviour score, generated from the BIEA, served as the criterion variable. Sections three to ..... personality variables in the prediction of environmental ...

  7. The MetNet vehicle: a lander to deploy environmental stations for local and global investigations of Mars

    Science.gov (United States)

    Harri, Ari-Matti; Pichkadze, Konstantin; Zeleny, Lev; Vazquez, Luis; Schmidt, Walter; Alexashkin, Sergey; Korablev, Oleg; Guerrero, Hector; Heilimo, Jyri; Uspensky, Mikhail; Finchenko, Valery; Linkin, Vyacheslav; Arruego, Ignacio; Genzer, Maria; Lipatov, Alexander; Polkko, Jouni; Paton, Mark; Savijärvi, Hannu; Haukka, Harri; Siili, Tero; Khovanskov, Vladimir; Ostesko, Boris; Poroshin, Andrey; Diaz-Michelena, Marina; Siikonen, Timo; Palin, Matti; Vorontsov, Viktor; Polyakov, Alexander; Valero, Francisco; Kemppinen, Osku; Leinonen, Jussi; Romero, Pilar

    2017-02-01

    Investigations of global and related local phenomena on Mars such as atmospheric circulation patterns, boundary layer phenomena, water, dust and climatological cycles and investigations of the planetary interior would benefit from simultaneous, distributed in situ measurements. Practically, such an observation network would require low-mass landers, with a high packing density, so a large number of landers could be delivered to Mars with the minimum number of launchers.The Mars Network Lander (MetNet Lander; MNL), a small semi-hard lander/penetrator design with a payload mass fraction of approximately 17 %, has been developed, tested and prototyped. The MNL features an innovative Entry, Descent and Landing System (EDLS) that is based on inflatable structures. The EDLS is capable of decelerating the lander from interplanetary transfer trajectories down to a surface impact speed of 50-70 m s-1 with a deceleration of design is ≈ 24 kg, with ≈ 4 kg of mass available for the payload.The EDLS is designed to orient the penetrator for a vertical impact. As the payload bay will be embedded in the surface materials, the bay's temperature excursions will be much less than if it were fully exposed on the Martian surface, allowing a reduction in the amount of thermal insulation and savings on mass.The MNL is well suited for delivering meteorological and atmospheric instruments to the Martian surface. The payload concept also enables the use of other environmental instruments. The small size and low mass of a MNL makes it ideally suited for piggy-backing on larger spacecraft. MNLs are designed primarily for use as surface networks but could also be used as pathfinders for high-value landed missions.

  8. Environmental summary document for the Republic Geothermal, Inc. application for a geothermal loan guaranty project: 64 MW well field and 48 MW (net) geothermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Layton, D.W.; Powers, D.J.; Leitner, P.; Crow, N.B.; Gudiksen, P.H.; Ricker, Y.E.

    1979-07-01

    A comprehensive review and analysis is provided of the environmental consequences of (1) guaranteeing a load for the completion of the 64 MW well field and the 48 MW (net) power plant or (2) denying a guaranteed load that is needed to finish the project. Mitigation measures are discussed. Alternatives and their impacts are compared and some discussion is included on unavoidable adverse impacts. (MHR)

  9. BAYESIAN ENTROPY FOR SPATIAL SAMPLING DESIGN OF ENVIRONMENTAL DATA

    Science.gov (United States)

    Particulate Matter (PM) has been linked to widespread public health effects, including a range of serious respiratory and cardiovascular problems, and to reduced visibility in may parts of the United States, see the Environmental Protection Agency (EPA) report (2004) and relevant...

  10. Determination of technetium-99 in environmental samples: A review

    DEFF Research Database (Denmark)

    Shi, Keliang; Hou, Xiaolin; Roos, Per

    2012-01-01

    Due to the lack of a stable technetium isotope, and the high mobility and long half-life, 99Tc is considered to be one of the most important radionuclides in safety assessment of environmental radioactivity as well as nuclear waste management. 99Tc is also an important tracer for oceanographic...

  11. A Protocol for Collecting Environmental DNA Samples From Streams

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Environmental DNA (eDNA) is DNA that has been released by an organism into its environment, such that the DNA can be found in air, water, or soil. In aquatic...

  12. Sampling design for spatially distributed hydrogeologic and environmental processes

    Science.gov (United States)

    Christakos, G.; Olea, R.A.

    1992-01-01

    A methodology for the design of sampling networks over space is proposed. The methodology is based on spatial random field representations of nonhomogeneous natural processes, and on optimal spatial estimation techniques. One of the most important results of random field theory for physical sciences is its rationalization of correlations in spatial variability of natural processes. This correlation is extremely important both for interpreting spatially distributed observations and for predictive performance. The extent of site sampling and the types of data to be collected will depend on the relationship of subsurface variability to predictive uncertainty. While hypothesis formulation and initial identification of spatial variability characteristics are based on scientific understanding (such as knowledge of the physics of the underlying phenomena, geological interpretations, intuition and experience), the support offered by field data is statistically modelled. This model is not limited by the geometric nature of sampling and covers a wide range in subsurface uncertainties. A factorization scheme of the sampling error variance is derived, which possesses certain atttactive properties allowing significant savings in computations. By means of this scheme, a practical sampling design procedure providing suitable indices of the sampling error variance is established. These indices can be used by way of multiobjective decision criteria to obtain the best sampling strategy. Neither the actual implementation of the in-situ sampling nor the solution of the large spatial estimation systems of equations are necessary. The required values of the accuracy parameters involved in the network design are derived using reference charts (readily available for various combinations of data configurations and spatial variability parameters) and certain simple yet accurate analytical formulas. Insight is gained by applying the proposed sampling procedure to realistic examples related

  13. Radioimmunoassay for the detection of polychlorinated dibenzo-P-dioxins in environmental samples: method description

    National Research Council Canada - National Science Library

    Sherry, J.P; ApSimon, J; Colier, L; Afghan, B.K; Albro, P.W

    1988-01-01

    ...) is a screening test that can, by the elimination of PCDD free samples from further conventional analysis, improve analytical efficiency and lower the cost of determining dioxins in environmental samples...

  14. Hanford Site Environmental Surveillance Master Sampling Schedule for Calendar Year 2011

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, Lynn E.

    2011-01-21

    This document contains the calendar year 2011 schedule for the routine collection of samples for the Surface Environmental Surveillance Project and the Drinking Water Monitoring Project. Each section includes sampling locations, sampling frequencies, sample types, and analyses to be performed. In some cases, samples are scheduled on a rotating basis. If a sample will not be collected in 2011, the anticipated year for collection is provided. Maps showing approximate sampling locations are included for media scheduled for collection in 2011.

  15. Hanford Site Environmental Surveillance Master Sampling Schedule for Calendar Year 2006

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, Lynn E.

    2006-01-27

    This document contains the calendar year 2006 schedules for the routine and non-routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project. Each section includes sampling locations, sample types, and analyses to be performed. In some cases, samples are scheduled on a rotating basis and may not be collected in 2006 in which case the anticipated year for collection is provided. The project document package (PDP) for Surface Environmental Surveillance contains the milestone control log for the issuing of CY06 Environmental Surveillance Master Sampling Schedule WBS 4.2.3.21.3.03, milestone: RL00430306 (4830106-12).

  16. Development of a One-Handed, Environmental Surface-Sampling Device

    Science.gov (United States)

    2016-05-01

    2015 4. TITLE AND SUBTITLE Development of a One-Handed, Environmental Surface-Sampling Device 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...the Mano sampling device is capable of collecting a Bacillus anthracis simulant in a laboratory setting with greater efficiency than the BiSKit device...incorporated into regular field use. 15. SUBJECT TERMS Environmental surface sampling Biological sampling kit (BiSKit) Bacillus anthracis 16

  17. The HLA-net GENE[RATE] pipeline for effective HLA data analysis and its application to 145 population samples from Europe and neighbouring areas.

    Science.gov (United States)

    Nunes, J M; Buhler, S; Roessli, D; Sanchez-Mazas, A

    2014-05-01

    In this review, we present for the first time an integrated version of the Gene[rate] computer tools which have been developed during the last 5 years to analyse human leukocyte antigen (HLA) data in human populations, as well as the results of their application to a large dataset of 145 HLA-typed population samples from Europe and its two neighbouring areas, North Africa and West Asia, now forming part of the Gene[va] database. All these computer tools and genetic data are, from now, publicly available through a newly designed bioinformatics platform, HLA-net, here presented as a main achievement of the HLA-NET scientific programme. The Gene[rate] pipeline offers user-friendly computer tools to estimate allele and haplotype frequencies, to test Hardy-Weinberg equilibrium (HWE), selective neutrality and linkage disequilibrium, to recode HLA data, to convert file formats, to display population frequencies of chosen alleles and haplotypes in selected geographic regions, and to perform genetic comparisons among chosen sets of population samples, including new data provided by the user. Both numerical and graphical outputs are generated, the latter being highly explicit and of publication quality. All these analyses can be performed on the pipeline after scrupulous validation of the population sample's characterisation and HLA typing reporting according to HLA-NET recommendations. The Gene[va] database offers direct access to the HLA-A, -B, -C, -DQA1, -DQB1, -DRB1 and -DPB1 frequencies and summary statistics of 145 population samples having successfully passed these HLA-NET 'filters', and representing three European subregions (South-East, North-East and Central-West Europe) and two neighbouring areas (North Africa, as far as Sudan, and West Asia, as far as South India). The analysis of these data, summarized in this review, shows a substantial genetic variation at the regional level in this continental area. These results have main implications for population genetics

  18. Investigation of environmental samples by low-level gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Koehler, M. [Nuclear Engineering and Analytics Rossendorf, Inc., Dresden (Germany); Niese, S. [Nuclear Engineering and Analytics Rossendorf, Inc., Dresden (Germany)

    1997-03-01

    The average sample number in our laboratory is about 200 per month (12% technical solid state, 30% geological solid state, 6% geological solid state with low mass, 12% biological, 11% water directly, 25% water after chemical separation, 4% others). In 54% of the measurements the background continuum, and though the detection limit, is determined only by the detector himself and not by the compton continuum from high energy lines in the sample. Some examples in the presented work aim to prove the advantages of gamma ray spectrometry in the underground laboratory Felsenkeller. (orig./DG)

  19. Latitudinal patterns of magnitude and interannual variability in net ecosystem exchange regulated by biological and environmental variables

    NARCIS (Netherlands)

    Yuan, W.P.; Luo, Y.Q.; Richardson, A.D.; Oren, R.; Luyssaert, S.; Janssens, I.A.; Ceulemans, R.; Zhou, X.H.; Grunwald, T.; Aubinet, M.; Berhofer, C.; Baldocchi, D.D.; Chen, J.Q.; Dunn, A.L.; Deforest, J.L.; Dragoni, D.; Goldstein, A.H.; Moors, E.J.; Munger, J.W.; Monson, R.K.; Suyker, A.E.; Star, G.; Scott, R.L.; Tenhunen, J.; Verma, S.B.; Vesala, T.; Wofsy, S.

    2009-01-01

    Over the last two and half decades, strong evidence showed that the terrestrial ecosystems are acting as a net sink for atmospheric carbon. However the spatial and temporal patterns of variation in the sink are not well known. In this study, we examined latitudinal patterns of interannual

  20. Niland development project geothermal loan guaranty: 49-MW (net) power plant and geothermal well field development, Imperial County, California: Environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    1984-10-01

    The proposed federal action addressed by this environmental assessment is the authorization of disbursements under a loan guaranteed by the US Department of Energy for the Niland Geothermal Energy Program. The disbursements will partially finance the development of a geothermal well field in the Imperial Valley of California to supply a 25-MW(e) (net) power plant. Phase I of the project is the production of 25 MW(e) (net) of power; the full rate of 49 MW (net) would be achieved during Phase II. The project is located on approximately 1600 acres (648 ha) near the city of Niland in Imperial County, California. Well field development includes the initial drilling of 8 production wells for Phase I, 8 production wells for Phase II, and the possible need for as many as 16 replacement wells over the anticipated 30-year life of the facility. Activities associated with the power plant in addition to operation are excavation and construction of the facility and associated systems (such as cooling towers). Significant environmental impacts, as defined in Council on Environmental Quality regulation 40 CFR Part 1508.27, are not expected to occur as a result of this project. Minor impacts could include the following: local degradation of ambient air quality due to particulate and/or hydrogen sulfide emissions, temporarily increased ambient noise levels due to drilling and construction activities, and increased traffic. Impacts could be significant in the event of a major spill of geothermal fluid, which could contaminate groundwater and surface waters and alter or eliminate nearby habitat. Careful land use planning and engineering design, implementation of mitigation measures for pollution control, and design and implementation of an environmental monitoring program that can provide an early indication of potential problems should ensure that impacts, except for certain accidents, will be minimized.

  1. GY SAMPLING THEORY IN ENVIRONMENTAL STUDIES 2: SUBSAMPLING ERROR MEASUREMENTS

    Science.gov (United States)

    Sampling can be a significant source of error in the measurement process. The characterization and cleanup of hazardous waste sites require data that meet site-specific levels of acceptable quality if scientifically supportable decisions are to be made. In support of this effort,...

  2. Filtration recovery of extracellular DNA from environmental water samples

    Science.gov (United States)

    qPCR methods are able to analyze DNA from microbes within hours of collecting water samples, providing the promptest notification and public awareness possible when unsafe pathogenic levels are reached. Health risk, however, may be overestimated by the presence of extracellular ...

  3. Measurement of Difficult-to-Measure Radionuclides in Environmental Samples

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Mun Ja; Choi, G S; Cho, Y. H.; Jeong, K. H.; Kim, H. R.; Park, D. W.

    2010-07-15

    Analytical procedures for technetium-99 and iodine-129 radioactivity in groundwater and seaweed sampled around radioactive waste disposal site were established. Quality control procedure for the radiochemical analysis was also prepared. Radiochemical analysis for technetium-99 in 72 groundwaters sampled around disposal site from 2007 to 2009 was performed. Radioactivities of technetium-99 were below MDA. The MDAs were obtained from <0.0643 to <0.0837 Bq/L. Radiochemical analysis for iodine-129 in 72 groundwaters was also carried out. Radioactivities of iodine-129 were below MDA. The MDAs were obtained from <0.0175 to <0.0470 Bq/L. Radioactivity of iodine-129 in 12 seaweeds sampled around disposal site was measured. Radioactivity of iodine-129 in the seaweeds were below MDA. The MDAs reached from <0.153 to <1.31 Bq/kg-fresh. For the verification of the analytical procedure, our lab. participated inter-comparison performance test organized by NPL. From the result of data evaluation by NPL, our lab obtained 'In Agreement' in the analysis of technetium-99 and iodine-129 of water sample

  4. Natural and anthropogenic {sup 236}U in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Steier, Peter [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria)], E-mail: peter.steier@univie.ac.at; Bichler, Max [Atominstitut der Osterreichischen Universitaeten, Technische Universitaet Wien, Stadionallee 2, Wien A-1020 (Austria); Keith Fifield, L. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia); Golser, Robin; Kutschera, Walter; Priller, Alfred [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria); Quinto, Francesca [Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, via Vivaldi 43, Caserta 81100 (Italy); Richter, Stephan [Euopean Commission, Directorate-General Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel (Belgium); Srncik, Michaela [Institut fuer Anorganische Chemie, Universitaet Wien, Waehringer Strasse 42, A-1090 Wien (Austria); Terrasi, Philippo [Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, via Vivaldi 43, Caserta 81100 (Italy); Wacker, Lukas [Institute for Particle Physics, HPK H25, Schafmattstrasse 20, CH-8093 Zuerich (Switzerland); Wallner, Anton [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria); Wallner, Gabriele [Institut fuer Anorganische Chemie, Universitaet Wien, Waehringer Strasse 42, A-1090 Wien (Austria); Wilcken, Klaus M. [Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, East Kilbride G75 OQF (United Kingdom); Maria Wild, Eva [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria)

    2008-05-15

    The interaction of thermal neutrons with {sup 235}U results in fission with a probability of {approx}85% and in the formation of {sup 236}U (t{sub 1/2} = 2.3 x 10{sup 7} yr) with a probability of {approx}15%. While anthropogenic {sup 236}U is, therefore, present in spent nuclear fuel at levels of {sup 236}U/U up to 10{sup -2}, the expected natural ratios in the pre-anthropogenic environment range from 10{sup -14} to 10{sup -10}. At VERA, systematic investigations suggest a detection limit below {sup 236}U/U = 5 x 10{sup -12} for samples of 0.5 mg U, while chemistry blanks of {approx}2 x 10{sup 7} atoms {sup 236}U per sample limit the sensitivity for smaller samples. We have found natural isotopic ratios in uranium reagents separated before the onset of human nuclear activities, in uranium ores from various origins and in water from a subsurface well in Bad Gastein, Austria. Anthropogenic contamination was clearly visible in soil and rivulet samples from Salzburg, Austria, whereas river sediments from Garigliano river (Southern Italy) were close to the detection limit. Finally, our natural in-house standard Vienna-KkU was calibrated against a certified reference material (IRMM REIMEP-18 A)

  5. A study on determination of potentially hazardous plutonium isotopes in environmental samples.

    Science.gov (United States)

    Strumińska-Parulska, Dagmara I

    2013-01-01

    Due to the lack of stable plutonium isotopes, and the high mobility as well as long half-life, plutonium is considered one of the most important radioelement in safety assessment of environmental radioactivity and nuclear waste management. A number of analytical methods have been developed over the past decades for determination of plutonium in environmental samples. The article discusses different analytical techniques and presents the results of plutonium isotopes determination by alpha spectrometry and accelerator mass spectrometry in environmental samples. The concentrations of plutonium isotopes in analyzed samples indicates its measurement is of great importance for environmental and safety assessment, especially in contaminated areas.

  6. Quality assurance guidance for field sampling and measurement assessment plates in support of EM environmental sampling and analysis activities

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    This document is one of several guidance documents developed by the US Department of Energy (DOE) Office of Environmental Restoration and Waste Management (EM). These documents support the EM Analytical Services Program (ASP) and are based on applicable regulatory requirements and DOE Orders. They address requirements in DOE Orders by providing guidance that pertains specifically to environmental restoration and waste management sampling and analysis activities. DOE 5700.6C Quality Assurance (QA) defines policy and requirements to establish QA programs ensuring that risks and environmental impacts are minimized and that safety, reliability, and performance are maximized. This is accomplished through the application of effective management systems commensurate with the risks imposed by the facility and the project. Every organization supporting EM`s environmental sampling and analysis activities must develop and document a QA program. Management of each organization is responsible for appropriate QA program implementation, assessment, and improvement. The collection of credible and cost-effective environmental data is critical to the long-term success of remedial and waste management actions performed at DOE facilities. Only well established and management supported assessment programs within each EM-support organization will enable DOE to demonstrate data quality. The purpose of this series of documents is to offer specific guidance for establishing an effective assessment program for EM`s environmental sampling and analysis (ESA) activities.

  7. [Environmental tobacco smoke exposure in homes of Mexico City: analysis of environmental samples and children and women hair].

    Science.gov (United States)

    Barrientos-Gutiérrez, Tonatiuh; Reynales-Shigematsu, Luz Myriam; Avila-Tang, Erika; Wipfli, Heather; Lazcano-Ponce, Eduardo

    2007-01-01

    In Mexico no evaluation of environmental tobacco smoke exposure in homes or habitants has been conducted. The objective of this study is to quantify environmental nicotine in Mexico City homes, simultaneously evaluating nicotine levels in children and women. In July 2005 a convenience sample of 41 homes was selected, 20% without smokers, 80% with smokers. Nicotine passive monitors were allocated in homes for one week, obtaining samples of hair from inhabitant non-smoking women and children. Samples were taken to the Johns Hopkins University where nicotine was extracted and analyzed using gas chromatography. A survey of opinions and behaviors related to environmental tobacco smoke was conducted. Environmental nicotine concentrations had a median of 0.08 microg/m3 (IQR 0.01-0.64), in children's hair 0.05 ng/mg (IQR 0.05-0.29), and in women's hair 0.05 ng/mg (IQR 0.05-0.19). Environmental nicotine concentrations and in children's hair were highly correlated (rS=0.49), and increased with the number of smokers at home. The majority of adults surveyed showed support towards measures of environmental tobacco smoke control. Homes are important spaces of exposure to environmental tobacco smoke. Particularly high levels of exposure were observed in children's hair, attributable to the presence of environmental nicotine at home. Integral preventive activities to eliminate active smoking and to avoid tobacco consumption at home are required.

  8. Extraction techniques in speciation analysis of environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Morabito, R. [ENEA Casaccia, Rome (Italy). Environmental Dept.

    1995-02-01

    One of the main problems in speciation analysis is that the different species of metals are present in complex matrices at very low concentration levels. Thus it is almost always necessary to separate the analytes of concern from the matrix and to concentrate them up to detectable concentration levels. Special care should be paid during extraction in order to avoid any contamination of samples, losses and changes in speciation of analytes of concern. The most common extraction techniques for speciation analysis of Pb, Sn, Hg, Cr, As, Se and Sb in liquid and solid samples are presented and briefly discussed. Due to the large quantity of material to be covered, speciation of alkyl, aryl, and macromolecular compounds (porphyrines, thioneines, etc.) has not been taken into account. (orig.)

  9. Simultaneous determination of the actinides in small environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Sill, D.S.; Sill, C.W. [EG& G Idaho Inc., Idaho Falls, ID (United States)

    1994-12-31

    Simultaneous determination of all alpha activity has always been and continues to be a highly desirable option in radiochemical analysis. However, the usual practice of gross alpha counting samples of raw water evaporated to dryness in planchets, air dusts collected on filters, planchets full of soils, etc., and then reporting the results quantitatively is neither accurate nor reliable, since it is virtually impossible to determine the correct counting efficiency with which the count was actually made. Attempts to calibrate empirically for a given set of conditions are also of marginal value because of wide variability in the deposition patterns. Direct gross alpha counting of samples without chemical preparation is useful when the activity present is substantially higher than that from the natural activity in its surroundings, or when a rapid order-of-magnitude indication of alpha activity is desired. All too often the results of these {open_quotes}screening methods{close_quotes} are reported with precision and accuracy that they can not possibly have. Even is excess alpha activity is indicated, a gross alpha count cannot distinguish between a man-made transuranium (TRU) radionuclide and a naturally-occurring one. The current procedure provides a true {open_quotes}total alpha{close_quotes} while eliminating the problems just discussed.

  10. A note on {sup 207}Bi in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Bossew, P. [European Commission, DG Joint Research Centre, Institute of Environment and Sustainability, Radioactivity Environmental Monitoring Group. Via Fermi 1, I-21020 Ispra, Vatican City State, Holy See (Italy)]. E-mail: peter.bossew@jrc.it; Lettner, H. [Institute of Physics and Biophysics, University of Salzburg, Hellbrunner Strasse 34, A-5020 Salzburg (Austria)]. E-mail: herbert.lettner@sbg.ac.at; Hubmer, A. [Institute of Physics and Biophysics, University of Salzburg, Hellbrunner Strasse 34, A-5020 Salzburg (Austria)

    2006-07-01

    Traces of the radionuclide {sup 207}Bi were identified in soil and cryoconite (glacier sediment) samples from Alpine regions of Austria. This nuclide has been produced in thermonuclear explosions mainly in the early 1960s and subsequently dispersed in the atmosphere. Activity concentrations up to 22 Bq/kg d.m. have been found. The ratio {sup 207}Bi:{sup 137}Cs(global fallout) equals (1.70 {+-} 0.12)10{sup -3}, which is in accordance with literature data. When low levels of {sup 207}Bi are assessed by gamma spectrometry, corrections must be made for a gamma line produced in the lead shield by neutron activation due to cosmic neutrons.

  11. Measurement of actinides in environmental samples by Photo-Electron Rejecting Alpha Liquid Scintillation

    Energy Technology Data Exchange (ETDEWEB)

    Cadieux, J.R. [Westinghouse Savannah River Co., Aiken, SC (United States); Clark, S. [Savannah River Ecology Lab., Univ. of Georgia (United States); Fjeld, R.A.; Reboul, S.; Sowder, A. [Clemson Univ., SC (United States). Dept. of Environmental Systems Engineering

    1994-05-01

    This work describes the adaptation of extractive scintillation with a Photo-Electron Rejecting Alpha Liquid Scintillation (PERALS) (ORDELA, Inc.) spectrometer to the analysis of actinides in environmental samples from the Savannah River Site (SRS). Environmental quality assurance standards and actual water samples were treated by one of two methods; either a two step direct extraction, or for more complex samples, pretreatment by an extraction chromatographic separation prior to measurement of the alpha activity by PERALS.

  12. Environmental sampling plan for Kwajalein Atoll Lagoon: 2017 Kwajalein sampling event

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-07-01

    Since the early 1980s, the U.S DOE Marshall Islands Program at LLNL has provided radiological monitoring of the marine and terrestrial environment at nuclear affected atolls in the northern Marshall Islands. The fundamental aim of these studies was to identify the level and distribution of key residual fallout radionuclide in the environment, improve understanding of prevalent radiation exposure pathways, and develop predictive dose assessments for resettled and resettling atoll population groups. These data and information were essential in terms of guiding the development of effective and environmentally protective remedial measures, and promoting potential actions to improve on food safety and security.

  13. 9 CFR 147.12 - Procedures for collection, isolation, and identification of Salmonella from environmental samples...

    Science.gov (United States)

    2010-01-01

    ... sanitizing soap prior to the sampling. Outer clothing, including gloves, should be changed between visits to... strength skim milk from USDA-APHIS “Recommended Sample Collection Methods for Environmental Samples.... Autoclave the assembled DS sampler bundle and transfer it with sterile forceps or other aseptic method to a...

  14. Application of flow cytometry and cell sorting to the bacterial analysis of environmental aerosol samples

    Science.gov (United States)

    Flow cytometry (FCM) combined with viability staining is a useful tool in discerning viable bacteria in environmental samples where traditional culture methods may fail. Contamination of aerosol samples with dust and other non-biological particles can interfere with accurate sample analysis and ther...

  15. Long-lasting insecticidal mosquito nets: effects of washing processes on pesticide residues, and human and environmental exposure

    OpenAIRE

    Ouattara, Jean Pierre Nabléni

    2014-01-01

    Malaria is one of the public health problems in the world. More than 3.3 billion people are at risk of malaria. Children under the age of five year, and pregnant women are most severely affected. The disease is transmitted to human through the bite of an infected female mosquito of the genus Anopheles. Nowadays Long-Lasting Insecticidal Mosquito Nets (LNs) are the most popular and useful tools for malaria control. At the same time LNs face some challenges as the need for reliable methods to c...

  16. Net Locality

    DEFF Research Database (Denmark)

    de Souza e Silva, Adriana Araujo; Gordon, Eric

    Provides an introduction to the new theory of Net Locality and the profound effect on individuals and societies when everything is located or locatable. Describes net locality as an emerging form of location awareness central to all aspects of digital media, from mobile phones, to Google Maps...... of emerging technologies, from GeoCities to GPS, Wi-Fi, Wiki Me, and Google Android....

  17. Net Neutrality

    DEFF Research Database (Denmark)

    Savin, Andrej

    2017-01-01

    Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else.......Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else....

  18. Evaluating the Life Cycle Environmental Benefits and Trade-Offs of Water Reuse Systems for Net-Zero Buildings.

    Science.gov (United States)

    Hasik, Vaclav; Anderson, Naomi E; Collinge, William O; Thiel, Cassandra L; Khanna, Vikas; Wirick, Jason; Piacentini, Richard; Landis, Amy E; Bilec, Melissa M

    2017-02-07

    Aging water infrastructure and increased water scarcity have resulted in higher interest in water reuse and decentralization. Rating systems for high-performance buildings implicitly promote the use of building-scale, decentralized water supply and treatment technologies. It is important to recognize the potential benefits and trade-offs of decentralized and centralized water systems in the context of high-performance buildings. For this reason and to fill a gap in the current literature, we completed a life cycle assessment (LCA) of the decentralized water system of a high-performance, net-zero energy, net-zero water building (NZB) that received multiple green building certifications and compared the results with two modeled buildings (conventional and water efficient) using centralized water systems. We investigated the NZB's impacts over varying lifetimes, conducted a break-even analysis, and included Monte Carlo uncertainty analysis. The results show that, although the NZB performs better in most categories than the conventional building, the water efficient building generally outperforms the NZB. The lifetime of the NZB, septic tank aeration, and use of solar energy have been found to be important factors in the NZB's impacts. While these findings are specific to the case study building, location, and treatment technologies, the framework for comparison of water and wastewater impacts of various buildings can be applied during building design to aid decision making. As we design and operate high-performance buildings, the potential trade-offs of advanced decentralized water treatment systems should be considered.

  19. RadNet Map Interface for Near-Real-Time Radiation Monitoring Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — RadNet is a national network of monitoring stations that regularly collect air, precipitation, drinking water, and milk samples for analysis of radioactivity. The...

  20. Method validation and uncertainty evaluation of organically bound tritium analysis in environmental sample.

    Science.gov (United States)

    Huang, Yan-Jun; Zeng, Fan; Zhang, Bing; Chen, Chao-Feng; Qin, Hong-Juan; Wu, Lian-Sheng; Guo, Gui-Yin; Yang, Li-Tao; Shang-Guan, Zhi-Hong

    2014-08-01

    The analytical method for organically bound tritium (OBT) was developed in our laboratory. The optimized operating conditions and parameters were established for sample drying, special combustion, distillation, and measurement on a liquid scintillation spectrometer (LSC). Selected types of OBT samples such as rice, corn, rapeseed, fresh lettuce and pork were analyzed for method validation of recovery rate reproducibility, the minimum detection concentration, and the uncertainty for typical low level environmental sample was evaluated. The combustion water recovery rate of different dried environmental sample was kept at about 80%, the minimum detection concentration of OBT ranged from 0.61 to 0.89 Bq/kg (dry weight), depending on the hydrogen content. It showed that this method is suitable for OBT analysis of environmental sample with stable recovery rate, and the combustion water yield of a sample with weight about 40 g would provide sufficient quantity for measurement on LSC. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Detection of pyrethroid pesticides and their environmental degradation products in duplicate diet samples

    Science.gov (United States)

    The abstract is for an oral presentation at the Asilomar Conference on Mass Spectrometry: Mass Spectrometry in Environmental Chemistry, Toxicology, and Health. It describes analytical method development and sample results for determination of pyrethroid pesticides and environme...

  2. Dynamic flow-through approaches for metal fractionation in environmentally relevant solid samples

    DEFF Research Database (Denmark)

    Miró, Manuel; Hansen, Elo Harald; Chomchoei, Roongrat

    2005-01-01

    In the recent decades, batchwise equilibrium-based single or sequential extraction schemes have been consolidated as analytical tools for fractionation analyses to assess the ecotoxicological significance of metal ions in solid environmental samples. However, taking into account that naturally...

  3. Rapid and Automated Determination of Plutonium and Neptunium in Environmental Samples

    DEFF Research Database (Denmark)

    Qiao, Jixin

    This thesis presents improved analytical methods for rapid and automated determination of plutonium and neptunium in environmental samples using sequential injection (SI) based chromatography and inductively coupled plasma mass spectrometry (ICP-MS). The progress of methodology development...... in this work consists of 5 subjects stated as follows: 1) Development and optimization of an SI-anion exchange chromatographic method for rapid determination of plutonium in environmental samples in combination of inductively coupled plasma mass spectrometry detection (Paper II); (2) Methodology development...... and optimization for rapid determination of plutonium in environmental samples using SIextraction chromatography prior to inductively coupled plasma mass spectrometry (Paper III); (3) Development of an SI-chromatographic method for simultaneous determination of plutonium and neptunium in environmental samples...

  4. Teaching Tennis for Net Success.

    Science.gov (United States)

    Young, Bryce

    1989-01-01

    A program for teaching tennis to beginners, NET (Net Easy Teaching) is described. The program addresses three common needs shared by tennis students: active involvement in hitting the ball, clearing the net, and positive reinforcement. A sample lesson plan is included. (IAH)

  5. A comparative study of extraction and purification methods for environmental DNA from soil and sludge samples

    OpenAIRE

    Roh, Changhyun; Villatte, Francois; Kim, Byung-Gee; Schmid, Rolf D.

    2006-01-01

    An important prerequisite for a successful metagenome library construction is an efficient extraction procedure for DNA out of environmental samples. In this study we compared three indirect and four direct extraction methods, including a commercial kit, in terms of DNA yield, purity and time requirement. A special focus was set on methods which are appropriate for the extraction of environmental DNA (eDNA) from very limited sample sizes (0.1 g) to enable a highly parallel approach. Direct ex...

  6. Hanford Site Environmental Surveillance Master Sampling Schedule for Calendar Year 2005

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, Lynn E.

    2005-01-19

    Environmental surveillance of the Hanford Site and surrounding areas is conducted by the Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy (DOE). Sampling is conducted to evaluate levels of radioactive and nonradioactive pollutants in the Hanford environs. This document contains the calendar year 2005 schedules for the routine and non-routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project.

  7. Zoonotic pathogens isolated from wild animals and environmental samples at two California wildlife hospitals.

    Science.gov (United States)

    Siembieda, Jennifer L; Miller, Woutrina A; Byrne, Barbara A; Ziccardi, Michael H; Anderson, Nancy; Chouicha, Nadira; Sandrock, Christian E; Johnson, Christine K

    2011-03-15

    To determine types and estimate prevalence of potentially zoonotic enteric pathogens shed by wild animals admitted to either of 2 wildlife hospitals and to characterize distribution of these pathogens and of aerobic bacteria in a hospital environment. Cross-sectional study. Fecal samples from 338 animals in 2 wildlife hospitals and environmental samples from 1 wildlife hospital. Fecal samples were collected within 24 hours of hospital admission. Environmental samples were collected from air and surfaces. Samples were tested for zoonotic pathogens via culture techniques and biochemical analyses. Prevalence of pathogen shedding was compared among species groups, ages, sexes, and seasons. Bacterial counts were determined for environmental samples. Campylobacter spp, Vibrio spp, Salmonella spp, Giardia spp, and Cryptosporidium spp (alone or in combination) were detected in 105 of 338 (31%) fecal samples. Campylobacter spp were isolated only from birds. Juvenile passerines were more likely to shed Campylobacter spp than were adults; prevalence increased among juvenile passerines during summer. Non-O1 serotypes of Vibrio cholerae were isolated from birds; during an oil-spill response, 9 of 10 seabirds screened were shedding this pathogen, which was also detected in environmental samples. Salmonella spp and Giardia spp were isolated from birds and mammals; Cryptosporidium spp were isolated from mammals only. Floors of animal rooms had higher bacterial counts than did floors with only human traffic. Potentially zoonotic enteric pathogens were identified in samples from several species admitted to wildlife hospitals, indicating potential for transmission if prevention is not practiced.

  8. Report for Detection of Biothreat Agents and Environmental Samples using the LLNL Virulence Array for DHS

    Energy Technology Data Exchange (ETDEWEB)

    Jaing, Crystal [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gardner, Shea [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McLoughlin, Kevin [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thissen, James [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jackson, Paul [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2011-04-18

    The objective of this project is to provide DHS a comprehensive evaluation of the current genomic technologies including genotyping, Taqman PCR, multiple locus variable tandem repeat analysis (MLVA), microarray and high-throughput DNA sequencing in the analysis of biothreat agents from complex environmental samples. This report focuses on the design, testing and results of samples on the Virulence Array.

  9. Discrimination between live and dead cellsin bacterial communities from environmental water samples analyzed by 454 pyrosequencing

    NARCIS (Netherlands)

    Nocker, Andreas; Richter-Heitmann, Tim; Montijn, Roy C; Schuren, Frank H J; Kort, Remco

    SUMMARY: The preferential detection of cells with intact membranes by sample treatment with propidium monoazide (PMA) in combination with PCR amplification is gaining in popularity. This study evaluates the effect of PMA on 454 pyrosequencing profiles of environmental water samples from a canal in

  10. Somatic Coliphage Profiles of Produce and Environmental Samples from Farms in Northern México.

    Science.gov (United States)

    Bartz, Faith E; Hodge, Domonique Watson; Heredia, Norma; de Aceituno, Anna Fabiszewski; Solís, Luisa; Jaykus, Lee-Ann; Garcia, Santos; Leon, Juan S

    2016-09-01

    Somatic coliphages were quantified in 459 produce and environmental samples from 11 farms in Northern Mexico to compare amounts of somatic coliphages among different types of fresh produce and environmental samples across the production steps on farms. Rinsates from cantaloupe melons, jalapeño peppers, tomatoes, and the hands of workers, soil, and water were collected during 2011-2012 at four successive steps on each farm, from the field before harvest through the packing facility, and assayed by FastPhage MPN Quanti-tray method. Cantaloupe farm samples contained more coliphages than jalapeño or tomato (p range food safety during fruit and vegetable production.

  11. Detection and transmission of Dientamoeba fragilis from environmental and household samples.

    Science.gov (United States)

    Stark, Damien; Roberts, Tamalee; Marriott, Deborah; Harkness, John; Ellis, John T

    2012-02-01

    Dientamoeba fragilis is a commonly occurring pathogenic protozoan often detected at higher rates in stool samples than Giardia intestinalis. However, little is known about its life cycle and mode of transmission. A total of 210 environmental and household samples were examined for the presence of D. fragilis by culture and polymerase chain reaction. Of 100 environmental samples, D. fragilis was detected only in untreated sewage. In the household samples D. fragilis was detected in 30% of household contacts tested and was not detected in any domestic pets. This study provides evidence that environmental transmission of D. fragilis is unlikely and that pets played no role in transmission of the disease in this study. Direct transmission from infected persons is the most likely mode of transmission for D. fragilis. The study also highlights the need for household contacts to be screened, given the propensity of close contacts to become infected with the organism.

  12. An Environmentally-Friendly Tourist Village in Egypt Based on a Hybrid Renewable Energy System––Part Two: A Net Zero Energy Tourist Village

    Directory of Open Access Journals (Sweden)

    Fahd Diab

    2015-07-01

    Full Text Available The main objective of this study is to discuss the economical and the environmental analysis of a net zero energy (NZE tourist village in Alexandria, Egypt, by maximizing the renewable energy fraction and minimizing the greenhouse gases (GHG emissions. The hybrid photovoltaics (PV/wind/diesel/battery system is found to be the optimum hybrid renewable energy system (HRES for the proposed tourist village under the study. The optimum HRES consists of 1600 kW of PV panels (58.09% solar energy penetration, 1000 kW of wind turbines (41.34% wind energy penetration, 1000 kW of power converters, 200 kW diesel generator (only 0.57% diesel generator penetration in addition to 2000 batteries with the capacity of 589 Ah each. The levelized cost of energy (COE from the optimum HRES is $0.17/kWh and the total net present cost (NPC of this system is $15,383,360. Additionally, the maximum renewable energy fraction is 99.1% and the amount of GHG emitted from the optimum HRES is only 31,289 kg/year, which is negligible in comparison with the other system configurations, therefore the optimum HRES can be considered as a green system. In addition to this, the achieved percentage of the capacity shortage and the unmet load in the optimal HRES is only 0% for both.

  13. Nontuberculous Mycobacteria Isolation from Clinical and Environmental Samples in Iran: Twenty Years of Surveillance

    Directory of Open Access Journals (Sweden)

    Ali Akbar Velayati

    2015-01-01

    Full Text Available Nontuberculous mycobacteria (NTM are opportunistic pathogens that are widely distributed in the environment. There is a lack of data on species distribution of these organisms from Iran. This study consists of a review of NTM articles published in Iran between the years 1992 and 2014. In this review, 20 articles and 14 case reports were identified. Among the 20 articles, 13 (65% studies focused on NTM isolates from clinical specimens, 6 (30% studies examined NTM isolates from environmental samples, and one (5% article included both clinical and environmental isolates. M. fortuitum (229/997; 23% was recorded as the most prevalent and rapid growing mycobacteria (RGM species in both clinical (28% and environmental (19% isolated samples (P < 0.05. Among slow growing mycobacteria (SGM, M. simiae (103/494; 21% demonstrated a higher frequency in clinical samples whereas in environmental samples it was M. flavescens (44/503; 9%. These data represent information from 14 provinces out of 31 provinces of Iran. No information is available in current published data on clinical or environmental NTM from the remaining 17 provinces in Iran. These results emphasize the potential importance of NTM as well as the underestimation of NTM frequency in Iran. NTM is an important clinical problem associated with significant morbidity and mortality in Iran. Continued research is needed from both clinical and environmental sources to help clinicians and researchers better understand and address NTM treatment and prevention.

  14. Nontuberculous Mycobacteria Isolation from Clinical and Environmental Samples in Iran: Twenty Years of Surveillance.

    Science.gov (United States)

    Velayati, Ali Akbar; Farnia, Parissa; Mozafari, Mohadese; Mirsaeidi, Mehdi

    2015-01-01

    Nontuberculous mycobacteria (NTM) are opportunistic pathogens that are widely distributed in the environment. There is a lack of data on species distribution of these organisms from Iran. This study consists of a review of NTM articles published in Iran between the years 1992 and 2014. In this review, 20 articles and 14 case reports were identified. Among the 20 articles, 13 (65%) studies focused on NTM isolates from clinical specimens, 6 (30%) studies examined NTM isolates from environmental samples, and one (5%) article included both clinical and environmental isolates. M. fortuitum (229/997; 23%) was recorded as the most prevalent and rapid growing mycobacteria (RGM) species in both clinical (28%) and environmental (19%) isolated samples (P mycobacteria (SGM), M. simiae (103/494; 21%) demonstrated a higher frequency in clinical samples whereas in environmental samples it was M. flavescens (44/503; 9%). These data represent information from 14 provinces out of 31 provinces of Iran. No information is available in current published data on clinical or environmental NTM from the remaining 17 provinces in Iran. These results emphasize the potential importance of NTM as well as the underestimation of NTM frequency in Iran. NTM is an important clinical problem associated with significant morbidity and mortality in Iran. Continued research is needed from both clinical and environmental sources to help clinicians and researchers better understand and address NTM treatment and prevention.

  15. Radiochemical separation of actinides for their determination in environmental samples and waste products

    Energy Technology Data Exchange (ETDEWEB)

    Gleisberg, B. [Nuclear Engineering and Analytics Rossendorf, Inc. (VKTA), Dresden (Germany)

    1997-03-01

    The determination of low level activities of actinides in environmental samples and waste products makes high demands on radiochemical separation methods. Artificial and natural actinides were analyzed in samples form the surrounding areas of NPP and of uranium mines, incorporation samples, solutions containing radioactive fuel, solutions and solids resutling from the process, and in wastes. The activities are measured by {alpha}-spectrometry and {gamma}-spectrometry. (DG)

  16. Improvements to sample processing and measurement to enable more widespread environmental application of tritium

    Energy Technology Data Exchange (ETDEWEB)

    Moran, James; Alexander, Thomas; Aalseth, Craig; Back, Henning; Mace, Emily; Overman, Cory; Seifert, Allen; Freeburg, Wilcox

    2017-08-01

    Previous measurements have demonstrated the wealth of information that tritium (T) can provide on environmentally relevant processes. We present modifications to sample preparation approaches that enable T measurement by proportional counting on small sample sizes equivalent to 120 mg of water and demonstrate the accuracy of these methods on a suite of standardized water samples. This enhanced method should provide the analytical flexibility needed to address persistent knowledge gaps in our understanding of T behavior in the environment.

  17. Large volume sample stacking in capillary zone electrophoresis for the monitoring of the degradation products of metribuzin in environmental samples.

    Science.gov (United States)

    Quesada-Molina, Carolina; García-Campaña, Ana M; Del Olmo-Iruela, Laura; Del Olmo, Monsalud

    2007-09-14

    A capillary zone electrophoresis (CZE) method with UV-vis detection has been developed for the simultaneous monitoring of the major degradation products of metribuzin, i.e. deaminometribuzin (DA), deaminodiketometribuzin (DADK) and diketometribuzin (DK). The dissociation acid constants have also been estimated by CE and no significant differences have been observed with the values obtained by applying other techniques. Optimum separation has been achieved in less than 9 min in 40 mM sodium tetraborate buffer, pH 9.5 by applying a voltage of 15kV at 25 degrees C and using p-aminobenzoic acid as internal standard. In order to increase sensitivity, large volume sample stacking (LVSS) with polarity switching has been applied as on-line pre-concentration methodology. Detection limits of 10, 10 and 20 ng/mL for DA, DADK and DK, respectively were obtained. The method has been applied to soil samples, after pressurized liquid extraction (PLE). Samples were extracted at high temperature (103 degrees C and 1500 psi) using methanol as extraction solvent and sodium sulphate as drying agent. This PLE procedure was followed by an off-line pre-concentration and sample clean-up procedure by solid-phase extraction (SPE) using a LiChrolut EN sorbent column. These last two procedures were also suitable for the direct treatment of groundwater samples before CE analysis. The combination of both off-line and on-line pre-concentration procedures provided a significant improvement in sensitivity. LVSS provided pre-concentration factors of 4, 36 and 28 for DK, DA and DADK, respectively and with SPE a pre-concentration of 500-fold for the case of water samples and of 2.5-fold in the case of soil samples was obtained. The method is suitable for the monitoring of these residues in environmental samples with high sensitivity, precision and satisfactory recoveries.

  18. Use of immunomagnetic separation for the detection of Desulfovibrio vulgaris from environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, R.; Hazen, T.C.; Joyner, D.C.; Kusel, K.; Singer, M.E.; Sitte, J.; Torok, T.

    2011-04-15

    Immunomagnetic separation (IMS) has proved highly efficient for recovering microorganisms from heterogeneous samples. Current investigation targeted the separation of viable cells of the sulfate-reducing bacterium, Desulfovibrio vulgaris. Streptavidin-coupled paramagnetic beads and biotin labeled antibodies raised against surface antigens of this microorganism were used to capture D. vulgaris cells in both bioreactor grown laboratory samples and from extremely low-biomass environmental soil and subsurface drilling samples. Initial studies on detection, recovery efficiency and viability for IMS were performed with laboratory grown D. vulgaris cells using various cell densities. Efficiency of cell isolation and recovery (i.e., release of the microbial cells from the beads following separation) was followed by microscopic imaging and acridine orange direct counts (AODC). Excellent recovery efficiency encouraged the use of IMS to capture Desulfovibrio spp. cells from low-biomass environmental samples. The environmental samples were obtained from a radionuclide-contaminated site in Germany and the chromium (VI)-contaminated Hanford site, an ongoing bioremediation project of the U.S. Department of Energy. Field deployable IMS technology may greatly facilitate environmental sampling and bioremediation process monitoring and enable transcriptomics and proteomics/metabolomics-based studies directly on cells collected from the field.

  19. Tritium analysis in environmental samples around Nuclear Power Plants and nationwide surveillance of radionuclides in some environmental samples(meat and drinking water)

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Woo; Han, Man Jung; Cho, Seong Won; Cho, Hong Jun; Oh, Hyeon Kyun; Lee, Jeong Min; Chang, Jae Sook [KORTIC, Taejon (Korea, Republic of)

    2001-12-15

    12 kind of environmental samples such as soil, underground water, seawater, etc. around the Nuclear Power Plants(NPP) and surface seawater around the Korea peninsula were sampled, For the samples of rain, pine-needle, air, seawater, underground water, chinese cabbage, grain of rice and milk sampled around NPP, and surface seawater and rain sampled all around country, tritium concentration was measured, The tritium concentration in the tap water and the gamma activity in the domestic and imported beef that were sampled at ward in the large city in Korea(Seoul, Pusan, Taegu, Taejun, Inchun, Kwangju) were analyzed for the meat and drinking waters. As the results of analyzing, tritium concentration in rain and tap water were very low all around country, but a little higher around the NPP than general surrounding. At the Wolsung NPP, tritium concentration was descend according to distance from the stack. Tritium activity of surface seawater around the Korea peninsula was also, very low. The measured radioactive elements in the beef is the same as the radioactive elements on the earth surface.

  20. Long Term RadNet Quality Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This RadNet Quality Data Asset includes all data since initiation and when ERAMS was expanded to become RadNet, name changed to reflect new mission. This includes...

  1. RESTful NET

    CERN Document Server

    Flanders, Jon

    2008-01-01

    RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa

  2. Rapid and automated determination of plutonium and neptunium in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, J.

    2011-03-15

    This thesis presents improved analytical methods for rapid and automated determination of plutonium and neptunium in environmental samples using sequential injection (SI) based chromatography and inductively coupled plasma mass spectrometry (ICP-MS). The progress of methodology development in this work consists of 5 subjects stated as follows: 1) Development and optimization of an SI-anion exchange chromatographic method for rapid determination of plutonium in environmental samples in combination of inductively coupled plasma mass spectrometry detection (Paper II); (2) Methodology development and optimization for rapid determination of plutonium in environmental samples using SI-extraction chromatography prior to inductively coupled plasma mass spectrometry (Paper III); (3) Development of an SI-chromatographic method for simultaneous determination of plutonium and neptunium in environmental samples (Paper IV); (4) Investigation of the suitability and applicability of 242Pu as a tracer for rapid neptunium determination using anion exchange chromatography in an SI-network coupled with inductively coupled plasma mass spectrometry (Paper V); (5) Exploration of macro-porous anion exchange chromatography for rapid and simultaneous determination of plutonium and neptunium within an SI system (Paper VI). The results demonstrate that the developed methods in this study are reliable and efficient for accurate assays of trace levels of plutonium and neptunium as demanded in different situations including environmental risk monitoring and assessment, emergency preparedness and surveillance of contaminated areas. (Author)

  3. Observed externalizing behavior: a developmental comparison of genetic and environmental influences across three samples.

    Science.gov (United States)

    Marceau, Kristine; Humbad, Mikhila N; Burt, S Alexandra; Klump, Kelly L; Leve, Leslie D; Neiderhiser, Jenae M

    2012-01-01

    Estimates of genetic and environmental influences on externalizing behavior are markedly inconsistent. In an attempt to refine and extend our knowledge of externalizing behavior, the current study examined the etiology of externalizing behavior using observational data in middle childhood and adolescence from three twin and sibling samples. Observational ratings offer a unique perspective on externalizing behavior rarely examined within behavioral genetic designs. Shared environmental influences were significant and moderate to large in magnitude across all three samples (i.e., 44, 77, and 38%), while genetic influences (31%) were significant only for the adolescent sample. All three samples showed greater shared environmental influences and less genetic influence than is typically found when examining self-, parent-, and teacher-reports of externalizing behavior. These findings are consistent with other reports that have found evidence for shared environmental influences on measures of child externalizing behavior-in direct contrast to a commonly held perception that shared environmental factors do not have significant influences on behavior beyond early childhood.

  4. Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin

    2010-01-01

    Fractionation of plutonium isotopes (238Pu, 239,240Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially...... to the treatment and disposal of nuclear waste from decommissioning.......Fractionation of plutonium isotopes (238Pu, 239,240Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially...

  5. The role of NAA in the environmental studies. Quantitative determination of heavy metals pollutant on environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Sutisna; Yusuf, Saeful; Fisli, Adel; Rukihati; Wardhani, Sri; Th Rina M [National Nuclear Energy Agency of Indonesia, Kawasan Puspiptek, Serpong (Indonesia)

    2003-03-01

    The neutron activation analysis technique was applied in the elemental analysis of environmental samples to solve an environmental pollution problem. We focused our study in the analysis of heavy metal which has potentially become a pollutant. The environmental samples analyzed were some water, sediment and an air particulate matter. The tap water sample was collected from five samplings points located at region of Serpong and Muria. Meanwhile the river water samples were taken from five samplings points of Ciliwung River. Eight samplings points of Cisadane river estuary located at Tanjung Burung were selected to collect sediment samples. Air particulate samples were collected from Jakarta Metropolitan and Serpong using high volume air sampler. Trace elements analyses of water samples were done using a combination of INAA and pre-concentration stage prior irradiation. All samples were irradiated at GA. Siwabessy reactor located at Serpong using a thermal neutron flux of about 10{sup 12} n.cm{sup -2}.sec{sup -1}. After cooling time, the samples irradiated were counted by a high resolution HPGe detector coupled to a multichannel analyzer. The quantitative analyses have been done using a comparative method to a fresh laboratory standard and we used some standard references materials to validate our analytical result. The obtained result from the tap water analysis show that the elements of As, Cr, Co, Cd, Mn, Sb and Zn could be determine quantitatively and they have a concentration range from about 0.02 {mu}g/L to 103.9 {mu}g/L. The analysis result of Ciliwung river water samples show that elements of Ag, As, Co, Cu, Fe, Hg, Mn, V and Zn are present in the range of 2.4 {mu}g/L to about 1365.8 {mu}g/L. Meanwhile some important elements were obtained in the sediments samples taken from Cisadane River estuary such as Ce (40.4 - 63.6 mg/kg), Co (15.2 - 40.2 mg/kg), Cr (21.6 - 57.8 mg/kg), Eu (1.2 - 1.8 mg/kg), Fe (7.0 - 16.8 mg/kg), Mn (887 - 1810 mg/kg) and V (160 - 558

  6. Petri Nets

    Indian Academy of Sciences (India)

    Associate Professor of. Computer Science and. Automation at the Indian. Institute of Science,. Bangalore. His research interests are broadly in the areas of stochastic modeling and scheduling methodologies for future factories; and object oriented modeling. GENERAL I ARTICLE. Petri Nets. 1. Overview and Foundations.

  7. Petri Nets

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 8. Petri Nets - Overview and Foundations. Y Narahari. General Article Volume 4 Issue 8 August 1999 pp ... Author Affiliations. Y Narahari1. Department ot Computer Science and Automation, Indian Institute of Science, Bangalore 560 012, India.

  8. Evaluation of a PCR assay on overgrown environmental samples cultured for Mycobacterium avium subsp. paratuberculosis.

    Science.gov (United States)

    Arango-Sabogal, Juan C; Labrecque, Olivia; Paré, Julie; Fairbrother, Julie-Hélène; Roy, Jean-Philippe; Wellemans, Vincent; Fecteau, Gilles

    2016-11-01

    Culture of Mycobacterium avium subsp. paratuberculosis (MAP) is the definitive antemortem test method for paratuberculosis. Microbial overgrowth is a challenge for MAP culture, as it complicates, delays, and increases the cost of the process. Additionally, herd status determination is impeded when noninterpretable (NI) results are obtained. The performance of PCR is comparable to fecal culture, thus it may be a complementary detection tool to classify NI samples. Our study aimed to determine if MAP DNA can be identified by PCR performed on NI environmental samples and to evaluate the performance of PCR before and after the culture of these samples in liquid media. A total of 154 environmental samples (62 NI, 62 negative, and 30 positive) were analyzed by PCR before being incubated in an automated system. Growth was confirmed by acid-fast bacilli stain and then the same PCR method was again applied on incubated samples, regardless of culture and stain results. Change in MAP DNA after incubation was assessed by converting the PCR quantification cycle (Cq) values into fold change using the 2-ΔCq method (ΔCq = Cq after culture - Cq before culture). A total of 1.6% (standard error [SE] = 1.6) of the NI environmental samples had detectable MAP DNA. The PCR had a significantly better performance when applied after culture than before culture (p = 0.004). After culture, a 66-fold change (SE = 17.1) in MAP DNA was observed on average. Performing a PCR on NI samples improves MAP culturing. The PCR method used in our study is a reliable and consistent method to classify NI environmental samples. © 2016 The Author(s).

  9. On the necessity of improving the environmental impacts of furniture and appliances in net-zero energy buildings.

    Science.gov (United States)

    Hoxha, Endrit; Jusselme, Thomas

    2017-10-15

    There is now clear evidence regarding the extensive use of furniture and appliances in daily human life, but there is less evidence of their impact on the environment. Responding to this gap in knowledge, this study focuses on an assessment of the environmental impacts of furniture and appliances as used in highly energy efficient buildings. Their primary energy, non-renewable energy and global warming potential indicators have been assessed by extending the boundaries of the Life Cycle Assessment (LCA) study beyond the building itself. In conclusion, we found that furniture and appliances were responsible for around 30% of greenhouse gas emissions and non-renewable energy consumption and 15% of primary energy consumption comparing to the overall impacts of the building. Since embodied impacts represent the largest values, the process for labelling the appliances' energy efficiency should encompass a life-cycle point of view, not just a usage point of view as the case currently. Among office appliances, computer equipment was ranked as the highest impacting element, especially laptops and monitors. As for domestic appliances, refrigerators and electric ovens had the biggest impacts. Concerning furniture, the greatest impacts were from office and kitchen cabinets. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. [Detection of Cryptospordium spp. in environmental water samples by FTA-PCR].

    Science.gov (United States)

    Zhang, Xiao-Ping; Zhu, Qian; He, Yan-Yan; Jiang, Li; Jiang, Shou-Fu

    2011-02-01

    To establish a FTA-polymeras chain reaction (FTA-PCR) method in detection of Cryptospordium spp. in different sources of water. The semi automated immunomagnetic separation (IMS) of Cryptospordium oocysts in environmental water samples was performed firstly, and then genomic DNA of Cryptospordium oocysts was extracted by FTA filters disk. Oligonucleotide primers were designed based on the DNA fragment of the 18 S rRNA gene from C. parvum. Plate DNA was amplified with primers in PCR. The control DNA samples from Toxoplasma gondii,Sarcocystis suihominis, Echinococcus granulosus, and Clonorchis sinensis were amplified simultaneously. All PCR products were detected by agar electrophoresis dyed with ethidium bromide. The 446 bp fragment of DNA was detected in all samples of C. parvum, C. andersoni, and C. baileyi, while it was not detected in control groups in laboratory. No positive samples were found from 10 samples collected from tape water in 5 districts of Shanghai City by FTA-PCR. Nine positive samples were detected totally from 70 different environmental water samples, there were 0 out of 15 samples from the source of tape water, 2 out of 25 from the Huangpu River, 5 out of 15 from rivers around the animal farmers, 1 out of 9 from output water of contaminating water treatment factory, 1 out of 6 from the out gate of living contaminating water. The 446 bp fragment was detected from all the amplified positive water samples. FTA-PCR is an efficient method for gene detection of Cryptospordium oocysts, which could be used in detection of environmental water samples. The contamination degree of Cryptospordium oocysts in the river water around animal farms is high.

  11. Some thoughts on problems associated with various sampling media used for environmental monitoring

    Science.gov (United States)

    Horowitz, A.J.

    1997-01-01

    Modern analytical instrumentation is capable of measuring a variety of trace elements at concentrations down into the single or double digit parts-per-trillion (ng l-1) range. This holds for the three most common sample media currently used in environmental monitoring programs: filtered water, whole-water and separated suspended sediment. Unfortunately, current analytical capabilities have exceeded the current capacity to collect both uncontaminated and representative environmental samples. The success of any trace element monitoring program requires that this issue be both understood and addressed. The environmental monitoring of trace elements requires the collection of calendar- and event-based dissolved and suspended sediment samples. There are unique problems associated with the collection and chemical analyses of both types of sample media. Over the past 10 years, reported ambient dissolved trace element concentrations have declined. Generally, these decreases do not reflect better water quality, but rather improvements in the procedures used to collect, process, preserve and analyze these samples without contaminating them during these steps. Further, recent studies have shown that the currently accepted operational definition of dissolved constituents (material passing a 0.45 ??m membrane filter) is inadequat owing to sampling and processing artifacts. The existence of these artifacts raises questions about the generation of accurate, precise and comparable 'dissolved' trace element data. Suspended sediment and associated trace elements can display marked short- and long-term spatial and temporal variability. This implies that spatially representative samples only can be obtained by generating composites using depth- and width-integrated sampling techniques. Additionally, temporal variations have led to the view that the determination of annual trace element fluxes may require nearly constant (e.g., high-frequency) sampling and subsequent chemical analyses

  12. Collecting Stream Samples for Water Quality. Module 16. Vocational Education Training in Environmental Health Sciences.

    Science.gov (United States)

    Consumer Dynamics Inc., Rockville, MD.

    This module, one of 25 on vocational education training for careers in environmental health occupations, contains self-instructional materials on collecting stream samples for water quality. Following guidelines for students and instructors and an introduction that explains what the student will learn are three lessons: (1) using a job aid to…

  13. A simple and rapid cultural method for detection of Enterobacter sakazakii in environmental samples

    NARCIS (Netherlands)

    Guillaume-Gentil, O.; Sonnard, V.; Kandhai, M.C.; Marugg, J.; Joosten, H.

    2005-01-01

    A method was developed to detect and identify Enterobacter sakazakii in environmental samples. The method is based on selective enrichment at 45 ± 0.5°C in lauryl sulfate tryptose broth supplemented with 0.5 M NaCl and 10 mg/liter vancomycin (mLST) for 22 to 24 h followed by streaking on tryptone

  14. Measuring environmental change in forest ecosystems by repeated soil sampling: A North American perspective

    Science.gov (United States)

    Gregory B. Lawrence; Ivan J. Fernandez; Daniel D. Richter; Donald S. Ross; Paul W. Hazlett; Scott W. Bailey; Rock Ouimet; Richard A. F. Warby; Arthur H. Johnson; Henry Lin; James M. Kaste; Andrew G. Lapenis; Timothy J. Sullivan

    2013-01-01

    Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest...

  15. Validation of dipslides as a tool for environmental sampling in a real-life hospital setting

    DEFF Research Database (Denmark)

    Ibfelt, T; Foged, Charlotte Bernhardt Laiho; Andersen, L P

    2014-01-01

    Environmental sampling in hospitals is becoming increasingly important because of the rise in nosocomial infections. In order to monitor and track these infections and optimize cleaning and disinfection, we need to be able to locate the fomites with the highest amount of microorganisms...

  16. Metallic speciation in environmental samples. La especiacion metalica en muestras medioambientales

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Uria, J.E.

    1994-01-01

    A review about chemical speciation in environmental samples was developed. Starting from definition of speciation, characteristic techniques and squemes for speciation more adequate for the characterization of the several organic/inorganic metal-species was considered. Finally, the possible future tendences of speciation techniques was also considered. (Author) 27 refs.

  17. Repurposing environmental DNA samples: Detecting the western pearlshell (Margaritifera falcata) as a proof of concept

    Science.gov (United States)

    Joseph C. Dysthe; Torrey Rodgers; Thomas W. Franklin; Kellie J. Carim; Michael K. Young; Kevin S. McKelvey; Karen E. Mock; Michael K. Schwartz

    2018-01-01

    Information on the distribution of multiple species in a common landscape is fundamental to effective conservation and management. However, distribution data are expensive to obtain and often limited to high-profile species in a system. A recently developed technique, environmental DNA (eDNA) sampling, has been shown to be more sensitive than traditional detection...

  18. Design of a WSN for the Sampling of Environmental Variability in Complex Terrain

    Directory of Open Access Journals (Sweden)

    Miguel A. Martín-Tardío

    2014-11-01

    Full Text Available In-situ environmental parameter measurements using sensor systems connected to a wireless network have become widespread, but the problem of monitoring large and mountainous areas by means of a wireless sensor network (WSN is not well resolved. The main reasons for this are: (1 the environmental variability distribution is unknown in the field; (2 without this knowledge, a huge number of sensors would be necessary to ensure the complete coverage of the environmental variability and (3 WSN design requirements, for example, effective connectivity (intervisibility, limiting distances and controlled redundancy, are usually solved by trial and error. Using temperature as the target environmental variable, we propose: (1 a method to determine the homogeneous environmental classes to be sampled using the digital elevation model (DEM and geometric simulations and (2 a procedure to determine an effective WSN design in complex terrain in terms of the number of sensors, redundancy, cost and spatial distribution. The proposed methodology, based on geographic information systems and binary integer programming can be easily adapted to a wide range of applications that need exhaustive and continuous environmental monitoring with high spatial resolution. The results show that the WSN design is perfectly suited to the topography and the technical specifications of the sensors, and provides a complete coverage of the environmental variability in terms of Sun exposure. However these results still need be validated in the field and the proposed procedure must be refined.

  19. Identification of Legionella from clinically diagnosed pneumonia patients and environmental samples.

    Science.gov (United States)

    Jahan, R; Tarafder, S; Saleh, A A; Miah, M R A

    2015-04-01

    Legionnaires' disease is a multisystem disease with life-threatening acute and severe form of pneumonia which is responsible for 2-9% pneumonia with high mortality. Eighty six respiratory tract samples and urine were collected from clinically diagnosed pneumonia patients and 12 water samples were collected from different environment. Identification of Legionella was done by culture and Polymerase Chain Reaction (PCR) of respiratory tract samples and environmental samples and Legionella Antigen (Ag) in urine was detected by Immunochromatographic test (ICT). Legionella was identified from 4 (4.65%) clinically diagnosed pneumonia patients of which 1(1.16%) case was culture positive, 1(1.16%) case was urine ICT positive and PCR was positive in all four cases. Of the 12 water samples tested, 4 (33.33%) samples were Legionella positive by PCR but culture results of these samples were negative. Identification of Legionella should be done by PCR in parallel with culture and urine ICT. Detection of Legionella in environmental samples is also needed to explore possible links between the water sources and disease transmission in population.

  20. Electrodeposition as an alternate method for preparation of environmental samples for iodide by AMS

    Energy Technology Data Exchange (ETDEWEB)

    Adamic, M.L., E-mail: Mary.Adamic@inl.gov [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States); Lister, T.E.; Dufek, E.J.; Jenson, D.D.; Olson, J.E. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States); Vockenhuber, C. [Laboratory of Ion Beam Physics, ETH Zurich, Otto-Stern-Weg 5, 8093 Zurich (Switzerland); Watrous, M.G. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States)

    2015-10-15

    This paper presents an evaluation of an alternate method for preparing environmental samples for {sup 129}I analysis by accelerator mass spectrometry (AMS) at Idaho National Laboratory. The optimal sample preparation method is characterized by ease of preparation, capability of processing very small quantities of iodide, and ease of loading into a cathode. Electrodeposition of iodide on a silver wire was evaluated using these criteria. This study indicates that the electrochemically-formed silver iodide deposits produce ion currents similar to those from precipitated silver iodide for the same sample mass. Precipitated silver iodide samples are usually mixed with niobium or silver powder prior to loading in a cathode. Using electrodeposition, the silver is already mixed with the sample and can simply be picked up with tweezers, placed in the sample die, and pressed into a cathode. The major advantage of this method is that the silver wire/electrodeposited silver iodide is much easier to load into a cathode.

  1. Hanford Environmental Monitoring Program schedule for samples, analyses, and measurements for calendar year 1985

    Energy Technology Data Exchange (ETDEWEB)

    Blumer, P.J.; Price, K.R.; Eddy, P.A.; Carlile, J.M.V.

    1984-12-01

    This report provides the CY 1985 schedule of data collection for the routine Hanford Surface Environmental Monitoring and Ground-Water Monitoring Programs at the Hanford Site. The purpose is to evaluate and report the levels of radioactive and nonradioactive pollutants in the Hanford environs, as required in DOE Order 5484.1. The routine sampling schedule provided herein does not include samples scheduled to be collected during FY 1985 in support of special studies, special contractor support programs, or for quality control purposes. In addition, the routine program outlined in this schedule is subject to modification during the year in response to changes in site operations, program requirements, or unusual sample results.

  2. Measurement of radium and thorium isotopes in environmental samples by alpha-spectrometry

    OpenAIRE

    Rodríguez Álvarez, María José; Sánchez, F.

    1995-01-01

    The final publication is available at Springer via http://dx.doi.org/10.1007/BF02035979 A new method for the determination of low-level radium and thorium isotopes in environmental samples by α-spectrometry is described. Thorium and radium isotopes were chemically separated from the same sample, by using the same tracer (229Th). Two different ways were explored for the concentration process in water samples, obtaining a chemical yield for Ra isotopes between 70–90% in both cases using KMnO...

  3. Quantitative Digital Autoradiography for Environmental Swipe Sample Prioritization: System design, Characterization, and Initial Measurements

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Benjamin S.; Zalavadia, Mital A.; Miller, Brian W.; Bliss, Mary; Olsen, Khris B.; Kasparek, Dustin M.; Clarke, Ardelia M.

    2017-07-17

    Environmental sampling and sample analyses by the International Atomic Energy Agency’s (IAEA) Network of Analytical Laboratories (NWAL) is a critical technical tool used to detect facility misuse under a Comprehensive Safeguards Agreement and to verify the absence of undeclared nuclear material activities under an Additional Protocol. Currently all environmental swipe samples (ESS) are screened using gamma spectrometry and x-ray fluorescence to estimate the amount of U and/or Pu in the ESS, to guide further analysis, and to assist in the shipment of ESS to the NWAL. Quantitative Digital Autoradiography for Environmental Samples (QDARES) is being developed to complement existing techniques through the use of a portable, real-time, high-spatial-resolution camera called the Ionizing-radiation Quantum Imaging Detector (iQID). The iQID constructs a spatial map of radionuclides within a sample or surface in real-time as charged particles (betas) and photons (gamma/x-rays) are detected and localized on an event-by-event basis. Knowledge of the location and nature of radioactive hot spots on the ESS could provide information for subsequent laboratory analysis. As a nondestructive technique, QDARES does not compromise the ESS chain of custody or subsequent laboratory analysis. In this paper we will present the system design and construction, characterization measurements with calibration sources, and initial measurements of ESS.

  4. An Optimized Method for Quantification of Pathogenic Leptospira in Environmental Water Samples.

    Science.gov (United States)

    Riediger, Irina N; Hoffmaster, Alex R; Casanovas-Massana, Arnau; Biondo, Alexander W; Ko, Albert I; Stoddard, Robyn A

    2016-01-01

    Leptospirosis is a zoonotic disease usually acquired by contact with water contaminated with urine of infected animals. However, few molecular methods have been used to monitor or quantify pathogenic Leptospira in environmental water samples. Here we optimized a DNA extraction method for the quantification of leptospires using a previously described Taqman-based qPCR method targeting lipL32, a gene unique to and highly conserved in pathogenic Leptospira. QIAamp DNA mini, MO BIO PowerWater DNA and PowerSoil DNA Isolation kits were evaluated to extract DNA from sewage, pond, river and ultrapure water samples spiked with leptospires. Performance of each kit varied with sample type. Sample processing methods were further evaluated and optimized using the PowerSoil DNA kit due to its performance on turbid water samples and reproducibility. Centrifugation speeds, water volumes and use of Escherichia coli as a carrier were compared to improve DNA recovery. All matrices showed a strong linearity in a range of concentrations from 106 to 10° leptospires/mL and lower limits of detection ranging from Leptospira in environmental waters (river, pond and sewage) which consists of the concentration of 40 mL samples by centrifugation at 15,000×g for 20 minutes at 4°C, followed by DNA extraction with the PowerSoil DNA Isolation kit. Although the method described herein needs to be validated in environmental studies, it potentially provides the opportunity for effective, timely and sensitive assessment of environmental leptospiral burden.

  5. Separation and characterization of nanoparticles in complex food and environmental samples by field-flow fractionation

    DEFF Research Database (Denmark)

    Kammer, Frank von der; Legros, Samuel; Hofmann, Thilo

    2011-01-01

    has been applied for separation of various types of NP (e.g., organic macromolecules, and carbonaceous or inorganic NPs) in different types of media (e.g., natural waters, soil extracts or food samples).FFF can be coupled to different types of detectors that offer additional information...... sample preparation, field-flow fractionation (FFF) is one of the most promising techniques to achieve relevant characterization.The objective of this review is to present the current status of FFF as an analytical separation technique for the study of NPs in complex food and environmental samples. FFF...... constituents in the samples require contradictory separation conditions. The potential of FFF analysis should always be evaluated bearing in mind the impact of the necessary sample preparation, the information that can be retrieved from the chosen detection systems and the influence of the chosen separation...

  6. Effects of holding time and measurement error on culturing Legionella in environmental water samples.

    Science.gov (United States)

    Flanders, W Dana; Kirkland, Kimberly H; Shelton, Brian G

    2014-10-01

    Outbreaks of Legionnaires' disease require environmental testing of water samples from potentially implicated building water systems to identify the source of exposure. A previous study reports a large impact on Legionella sample results due to shipping and delays in sample processing. Specifically, this same study, without accounting for measurement error, reports more than half of shipped samples tested had Legionella levels that arbitrarily changed up or down by one or more logs, and the authors attribute this result to shipping time. Accordingly, we conducted a study to determine the effects of sample holding/shipping time on Legionella sample results while taking into account measurement error, which has previously not been addressed. We analyzed 159 samples, each split into 16 aliquots, of which one-half (8) were processed promptly after collection. The remaining half (8) were processed the following day to assess impact of holding/shipping time. A total of 2544 samples were analyzed including replicates. After accounting for inherent measurement error, we found that the effect of holding time on observed Legionella counts was small and should have no practical impact on interpretation of results. Holding samples increased the root mean squared error by only about 3-8%. Notably, for only one of 159 samples, did the average of the 8 replicate counts change by 1 log. Thus, our findings do not support the hypothesis of frequent, significant (≥= 1 log10 unit) Legionella colony count changes due to holding. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Multiplex PCR for detection of botulinum neurotoxin-producing clostridia in clinical, food, and environmental samples.

    Science.gov (United States)

    De Medici, Dario; Anniballi, Fabrizio; Wyatt, Gary M; Lindström, Miia; Messelhäusser, Ute; Aldus, Clare F; Delibato, Elisabetta; Korkeala, Hannu; Peck, Michael W; Fenicia, Lucia

    2009-10-01

    Botulinum neurotoxin (BoNT), the most toxic substance known, is produced by the spore-forming bacterium Clostridium botulinum and, in rare cases, also by some strains of Clostridium butyricum and Clostridium baratii. The standard procedure for definitive detection of BoNT-producing clostridia is a culture method combined with neurotoxin detection using a standard mouse bioassay (SMB). The SMB is highly sensitive and specific, but it is expensive and time-consuming and there are ethical concerns due to use of laboratory animals. PCR provides a rapid alternative for initial screening for BoNT-producing clostridia. In this study, a previously described multiplex PCR assay was modified to detect all type A, B, E, and F neurotoxin genes in isolated strains and in clinical, food, environmental samples. This assay includes an internal amplification control. The effectiveness of the multiplex PCR method for detecting clostridia possessing type A, B, E, and F neurotoxin genes was evaluated by direct comparison with the SMB. This method showed 100% inclusivity and 100% exclusivity when 182 BoNT-producing clostridia and 21 other bacterial strains were used. The relative accuracy of the multiplex PCR and SMB was evaluated using 532 clinical, food, and environmental samples and was estimated to be 99.2%. The multiplex PCR was also used to investigate 110 freshly collected food and environmental samples, and 4 of the 110 samples (3.6%) were positive for BoNT-encoding genes.

  8. A simple and rapid cultural method for detection of Enterobacter sakazakii in environmental samples.

    Science.gov (United States)

    Guillaume-Gentil, O; Sonnard, V; Kandhai, M C; Marugg, J D; Joosten, H

    2005-01-01

    A method was developed to detect and identify Enterobacter sakazakii in environmental samples. The method is based on selective enrichment at 45+/-0.5 degrees C in lauryl sulfate tryptose broth supplemented with 0.5 M NaCl and 10 mg/liter vancomycin (mLST) for 22 to 24 h followed by streaking on tryptone soy agar with bile salts. When exposed to light during incubation at 37 degrees C, E. sakazakii produces yellow colonies within 24 h; identification was confirmed by testing for alpha-glucosidase activity and by using API 20E strips. All of the E. sakazakii strains tested (n = 99) were able to grow in mLST at 45+/-0.5 degrees C, whereas 35 of 39 strains of potential competitors, all belonging to the Enterobacteriaceae, were suppressed. A survey was carried out with 192 environmental samples from four different milk powder factories. Using this new protocol, E. sakazakii was isolated from almost 40% of the samples, whereas the reference procedure (enrichment in buffered peptone water, isolation on violet red bile glucose agar, and biochemical identification of randomly chosen colonies) only yielded 26% positive results. This selective method can be very useful for the rapid and reliable detection of E. sakazakii in environmental samples.

  9. Technical Note: New methodology for measuring viscosities in small volumes characteristic of environmental chamber particle samples

    Directory of Open Access Journals (Sweden)

    L. Renbaum-Wolff

    2013-01-01

    Full Text Available Herein, a method for the determination of viscosities of small sample volumes is introduced, with important implications for the viscosity determination of particle samples from environmental chambers (used to simulate atmospheric conditions. The amount of sample needed is < 1 μl, and the technique is capable of determining viscosities (η ranging between 10−3 and 103 Pascal seconds (Pa s in samples that cover a range of chemical properties and with real-time relative humidity and temperature control; hence, the technique should be well-suited for determining the viscosities, under atmospherically relevant conditions, of particles collected from environmental chambers. In this technique, supermicron particles are first deposited on an inert hydrophobic substrate. Then, insoluble beads (~1 μm in diameter are embedded in the particles. Next, a flow of gas is introduced over the particles, which generates a shear stress on the particle surfaces. The sample responds to this shear stress by generating internal circulations, which are quantified with an optical microscope by monitoring the movement of the beads. The rate of internal circulation is shown to be a function of particle viscosity but independent of the particle material for a wide range of organic and organic-water samples. A calibration curve is constructed from the experimental data that relates the rate of internal circulation to particle viscosity, and this calibration curve is successfully used to predict viscosities in multicomponent organic mixtures.

  10. Final report to the strategic environmental research and development program on near-net shape casting of uranium-6% niobium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gourdin, W.H.

    1996-01-01

    Fabrication methods traditionally used in the fabrication of depleted uranium parts within the Department of Energy (DOE) are extremely wasteful, with only 3% of the starting material actually appearing as finished product. The current effort, funded by the Strategic Environmental Research and Development Program (SERDP) at Los Alamos National Laboratory (LANL), Sandia National Laboratories, Albuquerque (SNLA), and Lawrence Livermore National Laboratory (LLNL), was conceived as a means to drastically reduce this inefficiency and the accompanying waste by demonstrating the technology to cast simple parts close to their final shape in molds made from a variety of materials. As a part of this coordinated study, LLNL was given, and has achieved, two primary objectives: (1) to demonstrate the feasibility of using refractory metal for reusable molds in the production of castings of uranium-6 wt% niobium alloy (U-6Nb); and (2) to demonstrate the utility of detailed simulations of thermal and fluid flow characteristics in the understanding and improvement of the near-net shape casting process. In both cases, our efforts were focused on a flat plate castings, which serve as simple prototypical parts. This report summarizes the results of LLNL work in each area.

  11. Materials and Methods for Streamlined Laboratory Analysis of Environmental Samples, FY 2016 Report

    Energy Technology Data Exchange (ETDEWEB)

    Addleman, Raymond S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Naes, Benjamin E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McNamara, Bruce K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Olsen, Khris B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chouyyok, Wilaiwan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Willingham, David G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Spigner, Angel C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-30

    The International Atomic Energy Agency (IAEA) relies upon laboratory analysis of environmental samples (typically referred to as “swipes”) collected during on-site inspections of safeguarded facilities to support the detection and deterrence of undeclared activities. Unfortunately, chemical processing and assay of the samples is slow and expensive. A rapid, effective, and simple extraction process and analysis method is needed to provide certified results with improved timeliness at reduced costs (principally in the form of reduced labor), while maintaining or improving sensitivity and efficacy. To address these safeguard needs the Pacific Northwest National Laboratory (PNNL) explored and demonstrated improved methods for environmental sample (ES) analysis. Improvements for both bulk and particle analysis were explored. To facilitate continuity and adoption, the new sampling materials and processing methods will be compatible with existing IAEA protocols for ES analysis. PNNL collaborated with Oak Ridge National Laboratory (ORNL), which performed independent validation of the new bulk analysis methods and compared performance to traditional IAEA’s Network of Analytical Laboratories (NWAL) protocol. ORNL efforts are reported separately. This report describes PNNL’s FY 2016 progress, which was focused on analytical application supporting environmental monitoring of uranium enrichment plants and nuclear fuel processing. In the future the technology could be applied to other safeguard applications and analytes related to fuel manufacturing, reprocessing, etc. PNNL’s FY 2016 efforts were broken into two tasks and a summary of progress, accomplishments and highlights are provided below. Principal progress and accomplishments on Task 1, Optimize Materials and Methods for ICP-MS Environmental Sample Analysis, are listed below. • Completed initial procedure for rapid uranium extraction from ES swipes based upon carbonate-peroxide chemistry (delivered to ORNL for

  12. Environmental study of two significant solid samples: gravitation dust sediment and soil.

    Science.gov (United States)

    Remeteiová, Dagmar; Rusnák, Radoslav; Kucanová, Eva; Fióová, Beáta; Ružičková, Silvia; Fekete, Ilona; Horváth, Márk; Dirner, Vojtech

    2012-01-01

    In this work are presented results of the complex study of two significant solid environmental samples: gravitation dust sediments (industrial pollutants, potential source of risk elements input to soils) and soils (component of the environment, potential source of risk elements input to food web). The first phase of this study was focused on the study of the significant chemical properties (phase composition, content of organic and inorganic carbon) of the dust and soil samples. In the second phase, the fractionation analysis was used on the evaluation of the mobility of chosen risk elements (Cu, Ni, Pb, Zn) in the studied samples. The single-step extractions were applied in the order of the isolation of the element forms (fractions), with different mobilities during defined ecological conditions by utilization of the following reagents: 1 mol dm(-3) NH(4)NO(3) for isolation of the "mobile" fraction, 0.05 mol dm(-3) ethylenediaminetetraacetic acid and 0.43 mol dm(-3) CH(3)COOH for isolation of the "mobilizable" fraction, and 2 mol dm(-3) HNO(3) for isolation of all releasable forms. On the basis of the results obtained in this study, it is possible to state that different origins and positions of solid environmental samples in the environment reflect in different chemical properties of their matrix. The different properties of the sample matrix result in different mobilities of risk elements in these kinds of samples. The fractionation analysis with single-step extraction for isolation element fractions is the method most suitable for easy checking of environmental pollution and for evaluation of risk elements cycle in the environment.

  13. Specific calibration problems for gammaspectrometric measurements of low-level radioactivity in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, D. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Wershofen, H. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    1997-03-01

    Gammaspectrometric measurements of low-level radioactivity in environmental samples are always done in a close source detector geometry. This geometry causes coincidence-summing effects for measurements of multi-photon emitting nuclides. The measurements of radioactivity in environmental samples are also influenced by the absorption of photons in the materials which have to be analysed. Both effects must be taken into account by correction factors with respect to an energy-specific calibration of the detector system for a given geometry and a given composition of the calibration source. The importance of these corrections is emphasized. It is the aim of the present paper to compare different experimental and theoretical methods for the determination of these correction factors published by various authors and to report about efforts to refine them. (orig.)

  14. Prevalence of L. Monocytogenes in Environmental Samples Collected in Dairy Plants of Sassari Province, Italy

    Science.gov (United States)

    Fadda, Antonio; Frongia, Giorgio; Sanna, Antonietta; Melillo, Rita

    2015-01-01

    Listeria (L.) monocytogenes is frequently isolated from food production environment and often persists in dairy plants despite vigorous sanitation regimes. In recent years several alert notifications were sent to Rapid Alert System for Food Products system as a consequence of Listeria monocytogenes contamination of ricotta cheese. After the alert of 2012, competent authority (Local Health Unit of Sassari Province) organised an environmental monitoring plan with the partnership of the Institute for Experimental Veterinary Medicine of Sardinia to verify analysis of dairy plants own-check according to Regulation (EC) N° 2073/05 and further modifications. In 2014 n. 665 processing areas samples of n. 50 dairy plants of Sassari Province were examined. UNI EN ISO 11290-1:2005 for detection of L. monocytogenes was used. Non-compliance in n. 5 diary plants are observed (n. 8 positive samples). Post-non-compliance environmental sanitisation was efficient and own-check plans included appropriate corrective actions. PMID:27800407

  15. Prevalence of L. monocytogenes in environmental samples collected in dairy plants of Sassari Province, Italy

    Directory of Open Access Journals (Sweden)

    Giovanni Terrosu

    2015-09-01

    Full Text Available Listeria (L. monocytogenes is frequently isolated from food production environment and often persists in dairy plants despite vigorous sanitation regimes. In recent years several alert notifications were sent to Rapid Alert System for Food Products system as a consequence of Listeria monocytogenes contamination of ricotta cheese. After the alert of 2012, competent authority (Local Health Unit of Sassari Province organised an environmental monitoring plan with the partnership of the Institute for Experimental Veterinary Medicine of Sardinia to verify analysis of dairy plants own-check according to Regulation (EC N° 2073/05 and further modifications. In 2014 n. 665 processing areas samples of n. 50 dairy plants of Sassari Province were examined. UNI EN ISO 11290-1:2005 for detection of L. monocytogenes was used. Non-compliance in n. 5 diary plants are observed (n. 8 positive samples. Post-non-compliance environmental sanitisation was efficient and own-check plans included appropriate corrective actions.

  16. Ectomycorrhizal identification in environmental samples of tree roots by Fourier-transform infrared (FTIR spectroscopy

    Directory of Open Access Journals (Sweden)

    Rodica ePena

    2014-05-01

    Full Text Available Roots of forest trees are associated with various ectomycorrhizal (ECM fungal species that are involved in nutrient exchange between host plant and the soil compartment. The identification of ECM fungi in small environmental samples is difficult. The present study tested the feasibility of attenuated total reflection Fourier-transform infrared (ATR-FTIR spectroscopy followed by hierarchical cluster analysis (HCA to discriminate in situ collected ECM fungal species. Root tips colonized by distinct ECM fungal species, i.e., Amanita rubescens, Cenococcum geophilum, Lactarius subdulcis, Russula ochroleuca, and Xerocomus pruinatus were collected in mono-specific beech (Fagus sylvatica and mixed deciduous forests in different geographic areas to investigate the environmental variability of the ECM FTIR signatures.A clear HCA discrimination was obtained for ECM fungal species independent of individual provenance. Environmental variability neither limited the discrimination between fungal species nor provided sufficient resolution to discern species sub-clusters for different sites. However, the de-convoluted FTIR spectra contained site-related spectral information for fungi with wide nutrient ranges, but not for Lactarius subdulcis, a fungus residing only in the litter layer. Specific markers for distinct ECM were identified in spectral regions associated with carbohydrates (i.e. mannans, lipids, and secondary protein structures. The present results support that FTIR spectroscopy coupled with multivariate analysis is a reliable and fast method to identify ECM fungal species in minute environmental samples. Moreover, our data suggest that the FTIR spectral signatures contain information on physiological and functional traits of ECM fungi.

  17. PCR for detection of Clostridium botulinum type C in avian and environmental samples.

    Science.gov (United States)

    Franciosa, G; Fenicia, L; Caldiani, C; Aureli, P

    1996-04-01

    A PCR was developed and applied for the detection of Clostridium botulinum type C in 18 avian and environmental samples collected during an outbreak of avian botulism, and the results were compared with those obtained by conventional methodologies based on the mouse bioassay. PCR and mouse bioassay results compared well (100%) after the enrichment of samples, but PCR results directly indicated the presence of this microorganism in six samples, while only one of these contained the type C botulinal neurotoxin before enrichment. The PCR assay was sensitive (limit of detection between 15 and 15 x 10(3) spores per PCR), specific (no amplification products were obtained with other clostridia), and rapid, since sonicated and heated samples provided enough template for amplification without any DNA purification. Eleven isolates of C. botulinum type C were recovered from mallards (Anas platyrhynchos), grey herons (Ardea cinerea), and mud during investigation of this outbreak.

  18. Evaluating the suitability of different environmental samples for tracing atmospheric pollution in industrial areas.

    Science.gov (United States)

    Francová, Anna; Chrastný, Vladislav; Šillerová, Hana; Vítková, Martina; Kocourková, Jana; Komárek, Michael

    2017-01-01

    Samples of lichens, snow and particulate matter (PM10, 24 h) are used for the source identification of air pollution in the heavily industrialized region of Ostrava, Upper Silesia, Czech Republic. An integrated approach that uses different environmental samples for metal concentration and Pb isotope analyses was applied. The broad range of isotope ratios in the samples indicates a combination of different pollution sources, the strongest among them being the metallurgical industry, bituminous coal combustion and traffic. Snow samples are proven as the most relevant indicator for tracing metal(loid)s and recent local contamination in the atmosphere. Lichens can be successfully used as tracers of the long-term activity of local and remote sources of contamination. The combination of PM10 with snow can provide very useful information for evaluation of current pollution sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Low-level determination of {sup 129}I in environmental samples by neutron activation

    Energy Technology Data Exchange (ETDEWEB)

    Chialian Tseng; Jiunnhsing Chao [National Tsing Hua University, Hsinchu (Taiwan). Nuclear Science and Technology Development Center

    1996-08-01

    Low-level determination of {sup 129} I and {sup 127} I ratio in environmental samples by neutron activation is described. The iodine was chemically separated from kombu (Laminaria japonica) samples by solvent extraction and subsequent reduction to an inorganic form prior to neutron irradiation, the activated {sup 126} I and {sup 130} I were measured by a germanium gamma-ray spectrometer after irradiation with a cooling time of 16 h. The lowest detection amount is estimated to be 10{sup -3} Bq or a corresponding {sup 129} I/{sup 127} I ratio of 10{sup -11}. The average {sup 129} I/{sup 127} I ratio for kombu samples, collected from local markets, was found to be 10{sup -10}, lower than those of terrestrial samples reported elsewhere. (Author).

  20. High efficiency environmental sampling with UV-cured peelable coatings (aka NuGoo project)

    Energy Technology Data Exchange (ETDEWEB)

    Henzl, Vladimir [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Junghans, Sylvia Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lakis, Rollin Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-21

    This report presents slides on CA Related Project (FY13-17); Environmental sampling by IAEA (not only) during CA; Decontamination gels; Cotton swipes vs. decon gel (FY15); Contamination removal study; The origins of the NuGoo; NuGoo – proof of concept; NuGoo – FY17 project ($250K); LED lamp – which one works and why; Selecting photoinitiator; Monomers and oligomers; Results.

  1. Transgenic zebrafish reveal tissue-specific differences in estrogen signaling in response to environmental water samples

    Science.gov (United States)

    Gorelick, Daniel A.; Iwanowicz, Luke R.; Hung, Alice L.; Blazer, Vicki; Halpern, Marnie E.

    2014-01-01

    Background: Environmental endocrine disruptors (EED) are exogenous chemicals that mimic endogenous hormones, such as estrogens. Previous studies using a zebrafish transgenic reporter demonstrated that the EEDs bisphenol A and genistein preferentially activate estrogen receptors (ER) in the larval heart compared to the liver. However, it was not known whether the transgenic zebrafish reporter was sensitive enough to detect estrogens from environmental samples, whether environmental estrogens would exhibit similar tissue-specific effects as BPA and genistein or why some compounds preferentially target receptors in the heart. Methods: We tested surface water samples using a transgenic zebrafish reporter with tandem estrogen response elements driving green fluorescent protein expression (5xERE:GFP). Reporter activation was colocalized with tissue-specific expression of estrogen receptor genes by RNA in situ hybridization. Results: Selective patterns of ER activation were observed in transgenic fish exposed to river water samples from the Mid-Atlantic United States, with several samples preferentially activating receptors in embryonic and larval heart valves. We discovered that tissue-specificity in ER activation is due to differences in the expression of estrogen receptor subtypes. ERα is expressed in developing heart valves but not in the liver, whereas ERβ2 has the opposite profile. Accordingly, subtype-specific ER agonists activate the reporter in either the heart valves or the liver. Conclusion: The use of 5xERE:GFP transgenic zebrafish has revealed an unexpected tissue-specific difference in the response to environmentally relevant estrogenic compounds. Exposure to estrogenic EEDs in utero is associated with adverse health effects, with the potentially unanticipated consequence of targeting developing heart valves.

  2. Use of superheated liquid dispersion technique for measuring alpha-emitting actinides in environmental samples

    Science.gov (United States)

    Wang, C. K.; Lim, W.; Pan, L. K.

    1994-12-01

    This paper presents a novel fast screening technique of measuring concentrations of alpha-emitting actinides in environmental samples. This novel technique is called superheated liquid dispersion (SLD), which involves dispersing fine superheated liquid (e.g. Freon-12) droplets into a mixture of glycerin and the actinide-containing chemical extractant. The interactions between alpha particles and superheated liquid droplets trigger bubbles. Therefore, one may relate the number of bubbles to the actinide concentration in the sample. The results obtained from the computer simulation and the experiment support the above claim.

  3. A comparison of microscopic and spectroscopic identification methods for analysis of microplastics in environmental samples.

    Science.gov (United States)

    Song, Young Kyoung; Hong, Sang Hee; Jang, Mi; Han, Gi Myung; Rani, Manviri; Lee, Jongmyoung; Shim, Won Joon

    2015-04-15

    The analysis of microplastics in various environmental samples requires the identification of microplastics from natural materials. The identification technique lacks a standardized protocol. Herein, stereomicroscope and Fourier transform infrared spectroscope (FT-IR) identification methods for microplastics (microplastics were significantly (p0.05) different. Depending on the number of samples and the microplastic size range of interest, the appropriate identification method should be determined; selecting a suitable identification method for microplastics is crucial for evaluating microplastic pollution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Minimum detection limit determination for the static SIMS analysis of environmental samples contaminated with tributyl phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Ingram, J.C.; Groenewold, G.S.; Appelhans, A.D.; Delmore, J.E.; Dahl, D.A. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1994-12-31

    Static secondary ion mass spectrometry (SIMS) has been demonstrated in this laboratory to be effective in the direct surface analysis of organic contaminants such as organophosphates adsorbed on mineral surfaces, vegetation, filters, and other environmental samples. Static SIMS is attractive for these applications due to the rapidness of the analysis which includes no sample preparation. Although static SIMS is a qualitative technique, minimum detection limit (MDL) information is critical to its application for screening environmental samples for contamination. Difficulties associated with determining MDL`s for static SIMS are similar to most other surface analysis methods which include unavailability of standards for quantification for most {open_quotes}real world{close_quotes} samples, ill-defined surface areas. The focus of this paper centers on determination of MDL`s for the detection of tributyl phosphate (TBP) on soils. Two different types of soils were investigated in order to compare the effect of soil type on the MDL for TBP. In surface analysis, the MDL is expressed in terms of the mass of the analyte divided by the surface area of the sample. The detection of TBP on soils is of considerable interest to DOE in its clean-up efforts at various sites as it was widely used in the DOE complex to extract U, Pu, Th, Np, and Am. Although TBP has limited toxicity, it may be useful as an indicator for the presence of Pu, U, and other contaminants at DOE burial sites.

  5. Environmental DNA sampling protocol - filtering water to capture DNA from aquatic organisms

    Science.gov (United States)

    Laramie, Matthew B.; Pilliod, David S.; Goldberg, Caren S.; Strickler, Katherine M.

    2015-09-29

    Environmental DNA (eDNA) analysis is an effective method of determining the presence of aquatic organisms such as fish, amphibians, and other taxa. This publication is meant to guide researchers and managers in the collection, concentration, and preservation of eDNA samples from lentic and lotic systems. A sampling workflow diagram and three sampling protocols are included as well as a list of suggested supplies. Protocols include filter and pump assembly using: (1) a hand-driven vacuum pump, ideal for sample collection in remote sampling locations where no electricity is available and when equipment weight is a primary concern; (2) a peristaltic pump powered by a rechargeable battery-operated driver/drill, suitable for remote sampling locations when weight consideration is less of a concern; (3) a 120-volt alternating current (AC) powered peristaltic pump suitable for any location where 120-volt AC power is accessible, or for roadside sampling locations. Images and detailed descriptions are provided for each step in the sampling and preservation process.

  6. Dielectrophoretic sample preparation for environmental monitoring of microorganisms: Soil particle removal.

    Science.gov (United States)

    Fatoyinbo, Henry O; McDonnell, Martin C; Hughes, Michael P

    2014-07-01

    Detection of pathogens from environmental samples is often hampered by sensors interacting with environmental particles such as soot, pollen, or environmental dust such as soil or clay. These particles may be of similar size to the target bacterium, preventing removal by filtration, but may non-specifically bind to sensor surfaces, fouling them and causing artefactual results. In this paper, we report the selective manipulation of soil particles using an AC electrokinetic microfluidic system. Four heterogeneous soil samples (smectic clay, kaolinitic clay, peaty loam, and sandy loam) were characterised using dielectrophoresis to identify the electrical difference to a target organism. A flow-cell device was then constructed to evaluate dielectrophoretic separation of bacteria and clay in a continous flow through mode. The average separation efficiency of the system across all soil types was found to be 68.7% with a maximal separation efficiency for kaolinitic clay at 87.6%. This represents the first attempt to separate soil particles from bacteria using dielectrophoresis and indicate that the technique shows significant promise; with appropriate system optimisation, we believe that this preliminary study represents an opportunity to develop a simple yet highly effective sample processing system.

  7. New developments in the extraction and determination of parabens in cosmetics and environmental samples. A review

    Energy Technology Data Exchange (ETDEWEB)

    Ocaña-González, Juan Antonio; Villar-Navarro, Mercedes [Department of Analytical Chemistry, Faculty of Chemistry, Universidad de Sevilla, c/Prof. García González, s/n. 41012 Seville (Spain); Ramos-Payán, María [Department of Analytical Chemistry, Faculty of Chemistry, Universidad de Sevilla, c/Prof. García González, s/n. 41012 Seville (Spain); Department of Analytical Chemistry, Lineberguer Cancer Center, The University of North Carolina at Chapel Hill, NC (United States); Fernández-Torres, Rut [Department of Analytical Chemistry, Faculty of Chemistry, Universidad de Sevilla, c/Prof. García González, s/n. 41012 Seville (Spain); Research Centre of Health and Environment (CYSMA), University of Huelva (Spain); Bello-López, Miguel Angel, E-mail: mabello@us.es [Department of Analytical Chemistry, Faculty of Chemistry, Universidad de Sevilla, c/Prof. García González, s/n. 41012 Seville (Spain)

    2015-02-09

    Highlights: • The analysis of parabens in cosmetics and environmental samples is reviewed. • Literature in this field from 1980 to 2003 is briefly discussed. • Determination and extraction methods in the last decade are discussed in-depth. - Abstract: Parabens are a family of synthetic esters of p-hydroxibenzoic acid widely used as preservatives in cosmetics and health-care products, among other daily-use commodities. Recently, their potential endocrine disrupting effects have raised concerns about their safety and their potential effects as emerging pollutants, leading to the regulation of the presence of parabens in commercial products by national and trans-national organizations. Also, this has led to an interest in developing sensible and reliable methods for their determination in environmental samples, cosmetics and health-care products. This paper is a comprehensive up-to-date review of the literature concerning the determination of parabens in environmental samples and cosmetic and health-care products. A brief revision of the literature concerning the traditional determination of parabens (1980–2003) is included, followed by an in-depth revision of the recent developments in both measurement and extraction methods for parabens in the last years (2003–2013). Finally, possible future perspectives in this field are proposed.

  8. Salmonella isolated from individual reptiles and environmental samples from terraria in private households in Sweden

    Science.gov (United States)

    2014-01-01

    Background This study investigates Salmonella spp. isolated from privately kept reptiles and from environmental samples such as bedding materials or water from the floor of the enclosures (terraria). It also compares isolation of Salmonella using Modified Semisolid Rappaport-Vassiliadis (MSRV) medium or selective enrichment in Rappaport-Vassiliadis-Soya (RVS) pepton broth. Cloacal swabs or swabs from the cloacal area were collected from 63 individual reptiles belonging to 14 households. All reptiles were from different terraria and from 62 of these, environmental samples were also collected. Sampling were done by the reptile owners according to written instructions and sent by mail immediately after sampling. All but three samples were analyzed within 24 h after collection. Colonies suspected for Salmonella were tested for agglutination and serotyped using the White-Kauffmann-Le Minor scheme. The relative sensitivity (se) and specificity (sp) for MSRV compared with RVS, and the agreement coefficient kappa (κ) were calculated. Results Salmonella was isolated from 50/63 (80%) terraria, either from the reptiles (31/63; 49%) or from bedding material (39/62; 63%). The most common subspecies was Salmonella enterica subspecies enterica followed by S. enterica subspecies diarizonae. In reptiles, the most common S. enterica subspecies enterica serovars were Java (n = 4) and Fluntern (n = 4), compared with the serovars Tennessee (n = 10) and Fluntern (n = 10) in the environmental samples. The exact same set of Salmonella subspecies and serovars were not isolated from the individual reptiles and the environmental samples from any of the households. Isolation using MSRV yielded more Salmonella isolates 61/113 (54%) than enrichment in RVS 57/125 (46%). The se was 97.9% (95% Confidence Interval 93.9-100), the sp 78.5% (95% CI 68.5-88.5) and the κ 0.74, indicating substantial agreement between the tests. Conclusions Salmonella can be expected to be present in

  9. Salmonella isolated from individual reptiles and environmental samples from terraria in private households in Sweden.

    Science.gov (United States)

    Wikström, Veronica O; Fernström, Lise-Lotte; Melin, Lennart; Boqvist, Sofia

    2014-01-24

    This study investigates Salmonella spp. isolated from privately kept reptiles and from environmental samples such as bedding materials or water from the floor of the enclosures (terraria). It also compares isolation of Salmonella using Modified Semisolid Rappaport-Vassiliadis (MSRV) medium or selective enrichment in Rappaport-Vassiliadis-Soya (RVS) pepton broth. Cloacal swabs or swabs from the cloacal area were collected from 63 individual reptiles belonging to 14 households. All reptiles were from different terraria and from 62 of these, environmental samples were also collected. Sampling were done by the reptile owners according to written instructions and sent by mail immediately after sampling. All but three samples were analyzed within 24 h after collection. Colonies suspected for Salmonella were tested for agglutination and serotyped using the White-Kauffmann-Le Minor scheme. The relative sensitivity (se) and specificity (sp) for MSRV compared with RVS, and the agreement coefficient kappa (κ) were calculated. Salmonella was isolated from 50/63 (80%) terraria, either from the reptiles (31/63; 49%) or from bedding material (39/62; 63%). The most common subspecies was Salmonella enterica subspecies enterica followed by S. enterica subspecies diarizonae. In reptiles, the most common S. enterica subspecies enterica serovars were Java (n = 4) and Fluntern (n = 4), compared with the serovars Tennessee (n = 10) and Fluntern (n = 10) in the environmental samples. The exact same set of Salmonella subspecies and serovars were not isolated from the individual reptiles and the environmental samples from any of the households. Isolation using MSRV yielded more Salmonella isolates 61/113 (54%) than enrichment in RVS 57/125 (46%). The se was 97.9% (95% Confidence Interval 93.9-100), the sp 78.5% (95% CI 68.5-88.5) and the κ 0.74, indicating substantial agreement between the tests. Salmonella can be expected to be present in environments where reptiles are

  10. Strategies for quantifying C(60) fullerenes in environmental and biological samples and implications for studies in environmental health and ecotoxicology.

    Science.gov (United States)

    Pycke, Benny F G; Benn, Troy M; Herckes, Pierre; Westerhoff, Paul; Halden, Rolf U

    2011-01-01

    Fullerenes are sphere-like molecules with unique physico-chemical properties, which render them of particular interest in biomedical research, consumer products and industrial applications. Human and environmental exposure to fullerenes is not a new phenomenon, due to a long history of hydrocarbon-combustion sources, and will only increase in the future, as incorporation of fullerenes into consumer products becomes more widespread for use as anti-aging, anti-bacterial or anti-apoptotic agents.An essential step in the determination of biological effects of fullerenes (and their surface-functionalized derivatives) is establishment of exposure-assessment techniques. However, in ecotoxicological studies, quantification of fullerenes is performed infrequently because robust, uniformly applicable analytical approaches have yet to be identified, due to the wide variety of sample types. Moreover, the unique physico-chemistry of fullerenes in aqueous matrices requires reassessment of conventional analytical approaches, especially in more complex biological matrices (e.g., urine, blood, plasma, milk, and tissue).Here, we present a review of current analytical approaches for the quantification of fullerenes and propose a consensus approach for determination of these nanomaterials in a variety of environmental and biological matrices.

  11. Evaluation of a New Environmental Sampling Protocol for Detection of Human Norovirus on Inanimate Surfaces

    Science.gov (United States)

    Lee, David; Treffiletti, Aimee; Hrsak, Mario; Shugart, Jill; Vinjé, Jan

    2015-01-01

    Inanimate surfaces are regarded as key vehicles for the spread of human norovirus during outbreaks. ISO method 15216 involves the use of cotton swabs for environmental sampling from food surfaces and fomites for the detection of norovirus genogroup I (GI) and GII. We evaluated the effects of the virus drying time (1, 8, 24, or 48 h), swab material (cotton, polyester, rayon, macrofoam, or an antistatic wipe), surface (stainless steel or a toilet seat), and area of the swabbed surface (25.8 cm2 to 645.0 cm2) on the recovery of human norovirus. Macrofoam swabs produced the highest rate of recovery of norovirus from surfaces as large as 645 cm2. The rates of recovery ranged from 2.2 to 36.0% for virus seeded on stainless-steel coupons (645.0 cm2) to 1.2 to 33.6% for toilet seat surfaces (700 cm2), with detection limits of 3.5 log10 and 4.0 log10 RNA copies. We used macrofoam swabs to collect environmental samples from several case cabins and common areas of a cruise ship where passengers had reported viral gastroenteritis symptoms. Seventeen (18.5%) of 92 samples tested positive for norovirus GII, and 4 samples could be sequenced and had identical GII.1 sequences. The viral loads of the swab samples from the cabins of the sick passengers ranged from 80 to 31,217 RNA copies, compared with 16 to 113 RNA copies for swab samples from public spaces. In conclusion, our swab protocol for norovirus may be a useful tool for outbreak investigations when no clinical samples are available to confirm the etiology. PMID:26116675

  12. New technique to take samples from environmental surfaces using flocked nylon swabs.

    Science.gov (United States)

    Hedin, G; Rynbäck, J; Loré, B

    2010-08-01

    Environmental surfaces near infected and/or colonised patients in hospitals are commonly contaminated with potentially pathogenic micro-organisms. At present, however, there is no standardised method for taking samples from surfaces in order to perform quantitative cultures. Usually contact plates or swabs are used, but these methods may give different results. The recovery rate of traditional swabbing, e.g. cotton or rayon, is poor. With a new type of swab utilising flocked nylon, the recovery may be enhanced up to three times compared with a rayon swab. In this study, we inoculated reference strains of Staphylococcus aureus and Enterococcus hirae onto a bedside table and took samples 1h later when inocula were dry. Sequential samples were taken from the same surface. A new sampling technique using two sequential nylon swabs for each sample was validated. The efficiency of the sampling, percentage recovery of the inoculum and the variation of culture results obtained from repeated experiments are described. Enhanced efficiency and higher recovery of inoculum were demonstrated using two sequential flocked nylon swabs for sampling. Copyright 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

  13. Measuring environmental change in forest ecosystems by repeated soil sampling: a North American perspective

    Science.gov (United States)

    Lawrence, Gregory B.; Fernandez, Ivan J.; Richter, Daniel D.; Ross, Donald S.; Hazlett, Paul W.; Bailey, Scott W.; Oiumet, Rock; Warby, Richard A.F.; Johnson, Arthur H.; Lin, Henry; Kaste, James M.; Lapenis, Andrew G.; Sullivan, Timothy J.

    2013-01-01

    Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest ecosystems through repeated measurements are largely nascent and uncoordinated. In eastern North America, repeated soil sampling has begun to provide valuable information on environmental problems such as air pollution. This review synthesizes the current state of the science to further the development and use of soil resampling as an integral method for recording and understanding environmental change in forested settings. The origins of soil resampling reach back to the 19th century in England and Russia. The concepts and methodologies involved in forest soil resampling are reviewed and evaluated through a discussion of how temporal and spatial variability can be addressed with a variety of sampling approaches. Key resampling studies demonstrate the type of results that can be obtained through differing approaches. Ongoing, large-scale issues such as recovery from acidification, long-term N deposition, C sequestration, effects of climate change, impacts from invasive species, and the increasing intensification of soil management all warrant the use of soil resampling as an essential tool for environmental monitoring and assessment. Furthermore, with better awareness of the value of soil resampling, studies can be designed with a long-term perspective so that information can be efficiently obtained well into the future to address problems that have not yet surfaced.

  14. Validation of the ANSR Listeria method for detection of Listeria spp. in environmental samples.

    Science.gov (United States)

    Wendorf, Michael; Feldpausch, Emily; Pinkava, Lisa; Luplow, Karen; Hosking, Edan; Norton, Paul; Biswas, Preetha; Mozola, Mark; Rice, Jennifer

    2013-01-01

    ANSR Listeria is a new diagnostic assay for detection of Listeria spp. in sponge or swab samples taken from a variety of environmental surfaces. The method is an isothermal nucleic acid amplification assay based on the nicking enzyme amplification reaction technology. Following single-step sample enrichment for 16-24 h, the assay is completed in 40 min, requiring only simple instrumentation. In inclusivity testing, 48 of 51 Listeria strains tested positive, with only the three strains of L. grayi producing negative results. Further investigation showed that L. grayi is reactive in the ANSR assay, but its ability to grow under the selective enrichment conditions used in the method is variable. In exclusivity testing, 32 species of non-Listeria, Gram-positive bacteria all produced negative ANSR assay results. Performance of the ANSR method was compared to that of the U.S. Department of Agriculture-Food Safety and Inspection Service reference culture procedure for detection of Listeria spp. in sponge or swab samples taken from inoculated stainless steel, plastic, ceramic tile, sealed concrete, and rubber surfaces. Data were analyzed using Chi-square and probability of detection models. Only one surface, stainless steel, showed a significant difference in performance between the methods, with the ANSR method producing more positive results. Results of internal trials were supported by findings from independent laboratory testing. The ANSR Listeria method can be used as an accurate, rapid, and simple alternative to standard culture methods for detection of Listeria spp. in environmental samples.

  15. Dehalococcoides as a Potential Biomarker Evidence for Uncharacterized Organohalides in Environmental Samples

    Directory of Open Access Journals (Sweden)

    Qihong Lu

    2017-09-01

    Full Text Available The massive production and improper disposal of organohalides resulted in worldwide contamination in soil and water. However, their environmental survey based on chromatographic methods was hindered by challenges in testing the extremely wide variety of organohalides. Dehalococcoides as obligate organohalide-respiring bacteria exclusively use organohalides as electron acceptors to support their growth, of which the presence could be coupled with organohalides and, therefore, could be employed as a biomarker of the organohalide pollution. In this study, Dehalococcoides was screened in various samples of bioreactors and subsurface environments, showing the wide distribution of Dehalococcoides in sludge and sediment. Further laboratory cultivation confirmed the dechlorination activities of those Dehalococcoides. Among those samples, Dehalococcoides accounting for 1.8% of the total microbial community was found in an anaerobic granular sludge sample collected from a full-scale bioreactor treating petroleum wastewater. Experimental evidence suggested that the influent wastewater in the bioreactor contained bromomethane which support the growth of Dehalococcoides. This study demonstrated that Dehalococcoides could be employed as a promising biomarker to test the present of organohalides in wastestreams or other environmental samples.

  16. Forensic source differentiation of petrogenic, pyrogenic, and biogenic hydrocarbons in Canadian oil sands environmental samples.

    Science.gov (United States)

    Wang, Zhendi; Yang, C; Parrott, J L; Frank, R A; Yang, Z; Brown, C E; Hollebone, B P; Landriault, M; Fieldhouse, B; Liu, Y; Zhang, G; Hewitt, L M

    2014-04-30

    To facilitate monitoring efforts, a forensic chemical fingerprinting methodology has been applied to characterize and differentiate pyrogenic (combustion derived) and biogenic (organism derived) hydrocarbons from petrogenic (petroleum derived) hydrocarbons in environmental samples from the Canadian oil sands region. Between 2009 and 2012, hundreds of oil sands environmental samples including water (snowmelt water, river water, and tailings pond water) and sediments (from river beds and tailings ponds) have been analyzed. These samples were taken from sites where assessments of wild fish health, invertebrate communities, toxicology and detailed chemistry are being conducted as part of the Canada-Alberta Joint Oil Sands Monitoring Plan (JOSMP). This study describes the distribution patterns and potential sources of PAHs from these integrated JOSMP study sites, and findings will be linked to responses in laboratory bioassays and in wild organisms collected from these same sites. It was determined that hydrocarbons in Athabasca River sediments and waters were most likely from four sources: (1) petrogenic heavy oil sands bitumen; (2) biogenic compounds; (3) petrogenic hydrocarbons of other lighter fuel oils; and (4) pyrogenic PAHs. PAHs and biomarkers detected in snowmelt water samples collected near mining operations imply that these materials are derived from oil sands particulates (from open pit mines, stacks and coke piles). Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  17. Comparing efficiency of American Fisheries Society standard snorkeling techniques to environmental DNA sampling techniques

    Science.gov (United States)

    Ulibarri, Roy M.; Bonar, Scott A.; Rees, Christopher B.; Amberg, Jon J.; Ladell, Bridget; Jackson, Craig

    2017-01-01

    Analysis of environmental DNA (eDNA) is an emerging technique used to detect aquatic species through water sampling and the extraction of biological material for amplification. Our study compared the efficacy of eDNA methodology to American Fisheries Society (AFS) standard snorkeling surveys with regard to detecting the presence of rare fish species. Knowing which method is more efficient at detecting target species will help managers to determine the best way to sample when both traditional sampling methods and eDNA sampling are available. Our study site included three Navajo Nation streams that contained Navajo Nation Genetic Subunit Bluehead Suckers Catostomus discobolus and Zuni Bluehead Suckers C. discobolus yarrowi. We first divided the entire wetted area of streams into consecutive 100-m reaches and then systematically selected 10 reaches/stream for snorkel and eDNA surveys. Surface water samples were taken in 10-m sections within each 100-m reach, while fish presence was noted via snorkeling in each 10-m section. Quantitative PCR was run on each individual water sample in quadruplicate to test for the presence or absence of the target species. With eDNA sampling techniques, we were able to positively detect both species in two out of the three streams. Snorkeling resulted in positive detection of both species in all three streams. In streams where the target species were detected with eDNA sampling, snorkeling detected fish at 11–29 sites/stream, whereas eDNA detected fish at 3–12 sites/stream. Our results suggest that AFS standard snorkeling is more effective than eDNA for detecting target fish species. To improve our eDNA procedures, the amount of water collected and tested should be increased. Additionally, filtering water on-site may improve eDNA techniques for detecting fish. Future research should focus on standardization of eDNA sampling to provide a widely operational sampling tool.

  18. Using Environmental Variables for Studying of the Quality of Sampling in Soil Mapping

    Directory of Open Access Journals (Sweden)

    A. Jafari

    2016-02-01

    profiles, which were then described, sampled, analyzed and classified according to the USDA soil classification system (16. The basic rationale is to set up a hypercube, the axes of which are the quantiles of rasters of environmental covariates, e.g., digital elevation model. Sampling evaluation was made using the HELS algorithm. This algorithm was written based on the study of Carre et al., 2007 (3 and run in R. Results and Discussion: The covariate dataset is represented by elevation, slope and wetness index (Table 2. All data layers were interpolated to a common grid of 30 m resolution. The size of the raster layer is 421 by 711 grid cells. Each of the three covariates is divided into four quantiles (Table 2. The hypercube character space has 43, i.e. 64 strata (Figure 5. The average number of grid cells within each stratum is therefore 4677 grid cells. The map of the covariate index (Figure 6 shows some patterns representative of the covariate variability. The values of the covariate index range between 0.0045 and 5.95. This means that some strata are very dense compared to others. This index allows us to explain if high or low relative weight of the sampling units (see below is due to soil sampling or covariate density. The strata with the highest density are in the areas with high geomorphology diversity. It means that geomorphology processes can cause the diversity and variability and it is in line with the geomorphology map (Figure 2. Of the 64 strata, 30.4% represent under-sampling, 60.2% represent adequate sampling and 9.4% represent over-sampling. Regarding the covariate index, most of the under-sampling appears in the high covariate index, where soil covariates are then highly variable. Actually, it is difficult to collect field samples in these highly variable areas (Figure 7. Also, most of the over-sampling was observed in areas with alow covariate index (Figure 7. We calculated the weights of all the sampling units and showed the results in Figure 8. One 64

  19. Temperature, salinity, and zooplankton species identification, number per sample, and wet weight per sample collected by MOCNESS net tow in the Gulf of Alaska from 13 October 1997 to 13 May 1999 (NODC Accession 0000102)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile, zooplantkon, and other data were collected using MOCNESS net tows casts from the ALPHA HELIX in the Gulf of Alaska. Data were collected from 13...

  20. Radiochemistry methods in DOE methods for evaluating environmental and waste management samples

    Energy Technology Data Exchange (ETDEWEB)

    Fadeff, S.K.; Goheen, S.C.

    1994-08-01

    Current standard sources of radiochemistry methods are often inappropriate for use in evaluating US Department of Energy environmental and waste management (DOE/EW) samples. Examples of current sources include EPA, ASTM, Standard Methods for the Examination of Water and Wastewater and HASL-300. Applicability of these methods is limited to specific matrices (usually water), radiation levels (usually environmental levels), and analytes (limited number). Radiochemistry methods in DOE Methods for Evaluating Environmental and Waste Management Samples (DOE Methods) attempt to fill the applicability gap that exists between standard methods and those needed for DOE/EM activities. The Radiochemistry chapter in DOE Methods includes an ``analysis and reporting`` guidance section as well as radiochemistry methods. A basis for identifying the DOE/EM radiochemistry needs is discussed. Within this needs framework, the applicability of standard methods and targeted new methods is identified. Sources of new methods (consolidated methods from DOE laboratories and submissions from individuals) and the methods review process will be discussed. The processes involved in generating consolidated methods add editing individually submitted methods will be compared. DOE Methods is a living document and continues to expand by adding various kinds of methods. Radiochemistry methods are highlighted in this paper. DOE Methods is intended to be a resource for methods applicable to DOE/EM problems. Although it is intended to support DOE, the guidance and methods are not necessarily exclusive to DOE. The document is available at no cost through the Laboratory Management Division of DOE, Office of Technology Development.

  1. A biogeochemical and genetic survey of acetylene fermentation by environmental samples and bacterial isolates

    Science.gov (United States)

    Miller, Laurence G.; Baesman, Shaun M.; Kirshtein, Julie; Voytek, Mary A.; Oremland, Ronald S.

    2013-01-01

    Anoxic samples (sediment and groundwater) from 13 chemically diverse field sites were assayed for their ability to consume acetylene (C2H2). Over incubation periods ranging from ˜ 10 to 80 days, selected samples from 7 of the 13 tested sites displayed significant C2H2 removal. No significant formation of ethylene was noted in these incubations; therefore, C2H2 consumption could be attributed to acetylene hydratase (AH) rather than nitrogenase activity. This putative AH (PAH) activity was observed in only 21% of the total of assayed samples, while amplification of AH genes from extracted DNA using degenerate primers derived from Pelobacter acetylenicus occurred in even fewer (9.8%) samples. Acetylene-fermenting bacteria were isolated as a pure culture from the sediments of a tidal mudflat in San Francisco Bay (SFB93) and as an enrichment culture from freshwater Searsville Lake (SV7). Comparison of 16S rDNA clone libraries revealed that SFB93 was closely related to P. carbolinicus, while SV7 consisted of several unrelated bacteria. AH gene was amplified from SFB93 but not SV7. The inability of the primers to generate amplicons in the SV7 enrichment, as well as from several of the environmental samples that displayed PAH activity, implied that either the primers were too highly constrained in their specificity or that there was a different type of AH gene in these environmental samples than occurs in P. acetylenicus. The significance of this work with regard to the search for life in the outer Solar System, where C2HL2 is abundant, is discussed.

  2. Molecular diversity and distribution of marine fungi across 130 European environmental samples.

    Science.gov (United States)

    Richards, Thomas A; Leonard, Guy; Mahé, Frédéric; Del Campo, Javier; Romac, Sarah; Jones, Meredith D M; Maguire, Finlay; Dunthorn, Micah; De Vargas, Colomban; Massana, Ramon; Chambouvet, Aurélie

    2015-11-22

    Environmental DNA and culture-based analyses have suggested that fungi are present in low diversity and in low abundance in many marine environments, especially in the upper water column. Here, we use a dual approach involving high-throughput diversity tag sequencing from both DNA and RNA templates and fluorescent cell counts to evaluate the diversity and relative abundance of fungi across marine samples taken from six European near-shore sites. We removed very rare fungal operational taxonomic units (OTUs) selecting only OTUs recovered from multiple samples for a detailed analysis. This approach identified a set of 71 fungal 'OTU clusters' that account for 66% of all the sequences assigned to the Fungi. Phylogenetic analyses demonstrated that this diversity includes a significant number of chytrid-like lineages that had not been previously described, indicating that the marine environment encompasses a number of zoosporic fungi that are new to taxonomic inventories. Using the sequence datasets, we identified cases where fungal OTUs were sampled across multiple geographical sites and between different sampling depths. This was especially clear in one relatively abundant and diverse phylogroup tentatively named Novel Chytrid-Like-Clade 1 (NCLC1). For comparison, a subset of the water column samples was also investigated using fluorescent microscopy to examine the abundance of eukaryotes with chitin cell walls. Comparisons of relative abundance of RNA-derived fungal tag sequences and chitin cell-wall counts demonstrate that fungi constitute a low fraction of the eukaryotic community in these water column samples. Taken together, these results demonstrate the phylogenetic position and environmental distribution of 71 lineages, improving our understanding of the diversity and abundance of fungi in marine environments. © 2015 The Authors.

  3. Impact of Environmental Enrichment on Perineuronal Nets in the Prefrontal Cortex following Early and Late Abstinence from Sucrose Self-Administration in Rats.

    Directory of Open Access Journals (Sweden)

    Megan Slaker

    Full Text Available Perineuronal nets (PNNs are aggregates of extracellular matrix that form structures surrounding a subset of GABAergic interneurons. The staining intensity of PNNs appears to be related to plasticity. Environmental enrichment (EE influences plasticity during adulthood: EE decreases the rewarding effects of drugs of abuse and diminishes both drug- and sucrose-seeking behavior. We determined the impact of EE on PNN intensity in the medial prefrontal cortex (mPFC in rats trained to self-administer sucrose. We examined the number and intensity of PNNs within the prelimbic (PL, infralimbic (IL, and orbitofrontal (OF regions of the mPFC of adult Long-Evans rats that were trained for sucrose self-administration followed by acute or chronic EE during abstinence and a cue-induced reinstatement test. Rats exposed to EE prior to a cue-induced reinstatement of sucrose seeking had an increase in PNN staining compared with rats in standard housing. Conversely, naïve rats given 1 day of EE had a decrease in PNN intensity in the PL, no change in the IL, and an increase in the OF. Our findings demonstrate that EE increases PNN intensity in the mPFC after sucrose training, suggesting that training enhances the ability of EE to increase PNN intensity. We further demonstrate an interaction between time of abstinence, duration of EE exposure, and cue-induced reinstatement. Our results suggest that increased PNN intensity after EE may alter the excitatory/inhibitory balance of mPFC neurons such that rats are less responsive to a sucrose cue.

  4. Molecular detection of native and invasive marine invertebrate larvae present in ballast and open water environmental samples collected in Puget Sound

    Science.gov (United States)

    Harvey, J.B.J.; Hoy, M.S.; Rodriguez, R.J.

    2009-01-01

    Non-native marine species have been and continue to be introduced into Puget Sound via several vectors including ship's ballast water. Some non-native species become invasive and negatively impact native species or near shore habitats. We present a new methodology for the development and testing of taxon specific PCR primers designed to assess environmental samples of ocean water for the presence of native and non-native bivalves, crustaceans and algae. The intergenic spacer regions (IGS; ITS1, ITS2 and 5.8S) of the ribosomal DNA were sequenced for adult samples of each taxon studied. We used these data along with those available in Genbank to design taxon and group specific primers and tested their stringency against artificial populations of plasmid constructs containing the entire IGS region for each of the 25 taxa in our study, respectively. Taxon and group specific primer sets were then used to detect the presence or absence of native and non-native planktonic life-history stages (propagules) from environmental samples of ballast water and plankton tow net samples collected in Puget Sound. This methodology provides an inexpensive and efficient way to test the discriminatory ability of taxon specific oligonucleotides (PCR primers) before creating molecular probes or beacons for use in molecular ecological applications such as probe hybridizations or microarray analyses. This work addresses the current need to develop molecular tools capable of diagnosing the presence of planktonic life-history stages from non-native marine species (potential invaders) in ballast water and other environmental samples. ?? 2008 Elsevier B.V.

  5. ISOLATION OF Cryptococcus neoformans FROM ENVIRONMENTAL SAMPLES COLLECTED IN SOUTHEASTERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Emeka I. NWEZE

    2015-08-01

    Full Text Available SUMMARY Cryptococcosis caused by Cryptococcus neoformans is the second most common fungal opportunistic pathogen and a lifethreatening infection with serious clinical manifestations especially in HIV/AIDS and other immunocompromised patients. In Nigeria, HIV/AIDS infection has reached an alarming level. Despite this, information on the presence of this fungus in clinical and environmental samples is very scanty in Nigeria and many other parts of Africa. We set out to evaluate the presence of Cryptococcus neoformans or C. gattii in pigeon droppings obtained from Southeastern Nigeria. One hundred and seventy-seven samples of pigeon droppings from six sample types were collected. The area covered comprised of ten cities and other locations spanning across five States in Nigeria. Using established techniques, Cryptococcus neoformans was isolated from 39 of the 177 (22.0% samples overall. No C. gattiiwas isolated. Most of the isolates (32.4% were recovered from dovecotes (11 of 34 followed closely by samples taken from markets (31.8%; seven of 22 and least from the church (4.0%; one of 25. The highest isolation rate (38.9% was found in samples from Enugu-Ezike(seven of 23 while the least came from Afikpoand the other locations each with 9.1% isolation rate. This is the first large-scale screening of Cryptococcus neoformans from pigeon droppings in Nigeria. The ecological and epidemiological significance of these findings are discussed.

  6. Environmental and mental conditions predicting the experience of involuntary musical imagery: An experience sampling method study.

    Science.gov (United States)

    Floridou, Georgia A; Müllensiefen, Daniel

    2015-05-01

    An experience sampling method (ESM) study on 40 volunteers was conducted to explore the environmental factors and psychological conditions related to involuntary musical imagery (INMI) in everyday life. Participants reported 6 times per day for one week on their INMI experiences, relevant contextual information and associated environmental conditions. The resulting data was modeled with Bayesian networks and led to insights into the interplay of factors related to INMI experiences. The activity that a person is engaged was found to play an important role in the experience of mind wandering, which in turn enables the experience of INMI. INMI occurrence is independent of the time of the day while the INMI trigger affects the subjective evaluation of the INMI experience. The results are compared to findings from earlier studies based on retrospective surveys and questionnaires and highlight the advantage of ESM techniques in research on spontaneous experiences like INMI. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. An improved method for the analysis of volatile polyfluorinated alkyl substances in environmental air samples

    Energy Technology Data Exchange (ETDEWEB)

    Jahnke, Annika; Ahrens, Lutz [Institute for Coastal Research, GKSS Research Centre, Department of Environmental Chemistry, Geesthacht (Germany); University of Lueneburg, Institute for Ecology and Environmental Chemistry, Faculty of Environmental Sciences, Lueneburg (Germany); Ebinghaus, Ralf; Temme, Christian [Institute for Coastal Research, GKSS Research Centre, Department of Environmental Chemistry, Geesthacht (Germany); Berger, Urs [Norwegian Institute for Air Research (NILU), Polar Environmental Centre, Tromsoe (Norway); Stockholm University, Department of Applied Environmental Science (ITM), Stockholm (Sweden); Barber, Jonathan L. [Lancaster University, Department of Environmental Science, Faculty of Science and Technology, Lancaster (United Kingdom)

    2007-02-15

    This article describes the optimisation and validation of an analytical method for the determination of volatile polyfluorinated alkyl substances (PFAS) in environmental air samples. Airborne fluorinated telomer alcohols (FTOHs) as well as fluorinated sulfonamides and sulfonamidoethanols (FOSAs/FOSEs) were enriched on glass-fibre filters (GFFs), polyurethane foams (PUFs) and XAD-2 resin by means of high-volume air samplers. Sensitive and selective determination was performed using gas chromatography/chemical ionisation-mass spectrometry (GC/CI-MS). Five mass-labelled internal standard (IS) compounds were applied to ensure the accuracy of the analytical results. No major blank problems were encountered. Recovery experiments were performed, showing losses of the most volatile compounds during extraction and extract concentration as well as strong signal enhancement for FOSEs due to matrix effects. Breakthrough experiments revealed losses of the most volatile FTOHs during sampling, while FOSAs/FOSEs were quantitatively retained. Both analyte losses and matrix effects could be remediated by application of adequate mass-labelled IS. Method quantification limits (MQLs) of the optimised method ranged from 0.2 to 2.5 pg/m{sup 3} for individual target compounds. As part of the method validation, an interlaboratory comparison of instrumental quantification methods was conducted. The applicability of the method was demonstrated by means of environmental air samples from an urban and a rural location in Northern Germany. (orig.)

  8. Speciation of Cr(VI) in environmental samples in the vicinity of the ferrochrome smelter

    Energy Technology Data Exchange (ETDEWEB)

    Sedumedi, Hilda N. [Department of Chemistry, Tshwane University of Technology, P.O. Box 56208, Arcadia, 0007, Pretoria (South Africa); Mandiwana, Khakhathi L., E-mail: MandiwanaKL@tut.ac.za [Department of Chemistry, Tshwane University of Technology, P.O. Box 56208, Arcadia, 0007, Pretoria (South Africa); Ngobeni, Prince; Panichev, Nikolay [Department of Chemistry, Tshwane University of Technology, P.O. Box 56208, Arcadia, 0007, Pretoria (South Africa)

    2009-12-30

    The impact of ferrochrome smelter on the contamination of its environment with toxic hexavalent chromium, Cr(VI), was assessed by analyzing smelter dusts, soil, grass and tree barks. For the separation of Cr(VI) from Cr(III), solid samples were treated with 0.1 M Na{sub 2}CO{sub 3} and filtered through hydrophilic PDVF 0.45 {mu}m filter prior to the determination of Cr(VI) by electrothermal atomic absorption spectrometry (ET-AAS). Ferrochrome smelter dust was found to contain significant levels of Cr(VI), viz. 43.5 {mu}g g{sup -1} (cyclone dust), 2710 {mu}g g{sup -1} (fine dust), and 7800 {mu}g g{sup -1} (slimes dust) which exceeded the maximum acceptable risk concentration (20 {mu}g g{sup -1}). The concentration of Cr(VI) in environmental samples of grass (3.4 {+-} 0.2), soil (7.7 {+-} 0.2), and tree bark (11.8 {+-} 1.2) collected in the vicinity of the chrome smelter were higher as compared with the same kind of samples collected from uncontaminated area. The results of the investigation show that ferrochrome smelter is a source of environmental pollution with contamination factors of Cr(VI) ranging between 10 and 50.

  9. Uranium monitoring tool for rapid analysis of environmental samples based on automated liquid-liquid microextraction.

    Science.gov (United States)

    Rodríguez, Rogelio; Avivar, Jessica; Ferrer, Laura; Leal, Luz O; Cerdà, Víctor

    2015-03-01

    A fully automated in-syringe (IS) magnetic stirring assisted (MSA) liquid-liquid microextraction (LLME) method for uranium(VI) determination was developed, exploiting a long path-length liquid waveguide capillary cell (LWCC) with spectrophotometric detection. On-line extraction of uranium was performed within a glass syringe containing a magnetic stirrer for homogenization of the sample and the successive reagents: cyanex-272 in dodecane as extractant, EDTA as interference eliminator, hydrochloric acid to make the back-extraction of U(VI) and arsenazo-III as chromogenic reagent to accomplish the spectrophotometric detection at 655 nm. Magnetic stirring assistance was performed by a specially designed driving device placed around the syringe body creating a rotating magnetic field in the syringe, and forcing the rotation of the stirring bar located inside the syringe. The detection limit (LOD) of the developed method is 3.2 µg L(-1). Its good interday precision (Relative Standard Deviation, RSD 3.3%), and its high extraction frequency (up to 6 h(-1)) makes of this method an inexpensive and fast screening tool for monitoring uranium(VI) in environmental samples. It was successfully applied to different environmental matrices: channel sediment certified reference material (BCR-320R), soil and phosphogypsum reference materials, and natural water samples, with recoveries close to 100%. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Determination of Organothiophosphate Insecticides in Environmental Water Samples by a Very Simple and Sensitive Spectrofluorimetric Method.

    Science.gov (United States)

    Bavili Tabrizi, Ahad; Abdollahi, Ali

    2015-10-01

    A simple, rapid and sensitive spectrofluorimetric method was developed for the determination of di-syston, ethion and phorate in environmental water samples. The procedure is based on the oxidation of these pesticides with cerium (IV) to produce cerium (III), and its fluorescence was monitored at 368 ± 3 nm after excitation at 257 ± 3 nm. The variables effecting oxidation of each pesticide were studied and optimized. Under the experimental conditions used, the calibration graphs were linear over the range 0.2-15, 0.1-13, 0.1-13 ng mL(-1) for di-syston, ethion and phorate, respectively. The limit of detection and quantification were in the range 0.034-0.096 and 0.112-0.316 ng mL(-1), respectively. Intra- and inter-day assay precisions, expressed as the relative standard deviation (RSD), were lower than 5.2 % and 6.7 %, respectively. Good recoveries in the range 86 %-108 % were obtained for spiked water samples. The proposed method was applied to the determination of studied pesticides in environmental water samples.

  11. Analytical methods for the endocrine disruptor compounds determination in environmental water samples.

    Science.gov (United States)

    Locatelli, Marcello; Sciascia, Francesco; Cifelli, Roberta; Malatesta, Luciano; Bruni, Pantaleone; Croce, Fausto

    2016-02-19

    The potential risk of exposure to different xenobiotics, which can modulate the endocrine system and represent a treat for the wellness of an increasing number of people, has recently drawn the attention of international environmental and health agencies. Several agents, characterized by structural diversity, may interfer with the normal endocrine functions that regulate cell growth, homeostasis and development. Substances such as pesticides, herbicides, plasticizers, metals, etc. having endocrine activity (EDCs) are used in agriculture and industry and are also used as drugs for humans and animals. A difficulty in the analytical determination of these substances is the complexity of the matrix in which they are present. In fact, the samples most frequently analyzed consist of groundwater and surface water, including influent and effluent of wastewater treatment plants and drinking water. In this review, several sample pretreatment protocols, assays and different instrumental techniques recently used in the EDCs determination have been considered. This review concludes with a paragraph in which the most recent hyphenated-instrument techniques are treated, highlighting their sensitivity and selectivity for the analyses of environmental water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Middlesex Sampling Plant environmental report for calendar year 1989, Middlesex, New Jersey

    Energy Technology Data Exchange (ETDEWEB)

    1990-05-01

    The environmental monitoring program, which began in 1980, was continued in 1989 at the former Middlesex Sampling Plant (MSP) site, located in the Borough of Middlesex, New Jersey. The MSP site is part of the Formerly Utilized Sites Remedial Action Program (FUSRAP), a Department of Energy (DOE) program to decontaminate or otherwise control sites where residual radioactive materials remain either from the early years of the nation's atomic energy program or from commercial operations causing conditions that Congress has authorized DOE to remedy. The monitoring program at MSP measures radon concentrations in air; external gamma radiation levels; and uranium and radium concentrations in surface water, groundwater, and sediment. Additionally, several nonradiological parameters are measured in groundwater samples. To verify that the site is in compliance with the DOE radiation protection standard (100 mrem/yr) and to assess its potential effect on public health, the radiation dose was calculated for a hypothetical maximally exposed individual. This report presents the findings of the environmental monitoring program conducted in the area of the Middlesex Sampling Plant (MSP) site during calendar year 1989. 17 refs., 16 figs., 16 tabs.

  13. Biochemical identification and numerical taxonomy of Aeromonas spp. isolated from environmental and clinical samples in Spain.

    Science.gov (United States)

    Miñana-Galbis, D; Farfán, M; Lorén, J G; Fusté, M C

    2002-01-01

    To study the phenotypic characteristics of Aeromonas spp. from environmental and clinical samples in Spain and to cluster these strains by numerical taxonomy. A collection of 202 Aeromonas strains isolated from bivalve molluscs, water and clinical samples was tested for 64 phenotypic properties; 91% of these isolates were identified at species level. Aeromonas caviae was predominant in bivalve molluscs and Aerom. bestiarum in freshwater samples. Cluster analyses revealed eight different phena: three containing more than one DNA-DNA hybridization group but including strains that belong to the same phenospecies complex (Aerom. hydrophila, Aerom. sobria and Aerom. caviae), Aerom. encheleia, Aerom. trota and three containing unidentified Aeromonas strains isolated from bivalve molluscs. Aeromonas spp. are widely distributed in environmental and clinical sources. A selection of 16 of the phenotypical tests chosen allowed the identification of most isolates (91%), although some strains remain unidentified, mainly isolates from bivalve molluscs, suggesting the presence of new Aeromonas species. Numerical taxonomy was not in total concordance with the identification of the studied strains. Numerical taxonomy of Aeromonas strains isolated from different sources revealed the presence of potentially pathogenic Aeromonas spp., especially in bivalve molluscs, and phena with unidentified strains that suggest new Aeromonas species.

  14. Headspace solid-phase microextraction of halogenated toluenes in environmental aqueous samples with polypropylene microporous membranes.

    Science.gov (United States)

    Carpinteiro, M I; Rodríguez, I; Cela, R; Ramil, M

    2009-04-03

    The optimization of the polypropylene microporous membrane based solid-phase microextraction (MMSPE) of several halogenated (Cl(-) and Br(-)) toluenes was carried out. The influence of several factors such as sampling mode, sample volume, stirring rate, ionic strength, exposure time, etc. on the performance of the microextraction process was thoroughly investigated. Under optimized conditions, analytes were concentrated onto a 2-cm long membrane exposed to the headspace (HS) of the sample vial containing 80mL of water with a 30% of sodium chloride. Equilibrium was achieved after a sampling period of 1h, at room temperature and vigorous magnetic stirring. After analytes desorption, with just 250 microL of n-hexane, they were determined by gas chromatography with micro-electron capture detection (GC-mu-ECD). The developed methodology was characterized and validated also by gas chromatography-mass spectrometry (GC-MS). The proposed approach presented good precision (RSDs of 6-15% and 2-8% under reproducibility and repeatability conditions, respectively) and linear responses (R(2): 0.990-0.999) over more than two order of magnitude concentration ranges for di- to penta-substituted species either with GC-MS or GC-mu-ECD detection. The absolute extraction efficiency was directly related with the lipophilic nature of the studied species and their volatile character, ranging between 27% and 47% for di- to pentahalotoluenes. Despite being an adsorption based methodology, no matrix effects were observed for complex environmental water matrices such as river water or treated wastewater. The proposed approach provided a very simple and low-cost microextraction alternative rendering adequate limits of quantification, in the low/sub ngL(-1) level, for environmental sample analysis of poly-halogenated toluenes.

  15. Highly efficient detection of paclobutrazol in environmental water and soil samples by time-resolved fluoroimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhenjiang, E-mail: lzj1984@ujs.edu.cn [School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013 (China); Wei, Xi [School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013 (China); The Affiliated First People' s Hospital of Jiangsu University, Zhenjiang 212002 (China); Ren, Kewei; Zhu, Gangbing; Zhang, Zhen; Wang, Jiagao; Du, Daolin [School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013 (China)

    2016-11-01

    A fast and ultrasensitive indirect competitive time-resolved fluoroimmunoassay (TRFIA) was developed for the analysis of paclobutrazol in environmental water and soil samples. Paclobutrazol hapten was synthesized and conjugated to bovine serum albumin (BSA) for producing polyclonal antibodies. Under optimal conditions, the 50% inhibitory concentration (IC{sub 50} value) and limit of detection (LOD, IC{sub 20} value) were 1.09 μg L{sup −} {sup 1} and 0.067 μg L{sup −} {sup 1}, respectively. The LOD of TRFIA was improved 30-fold compared to the already reported ELISA. There was almost no cross-reactivity of the antibody with the other structural analogues of triazole compounds, indicating that the antibody had high specificity. The average recoveries from spiked samples were in the range from 80.2% to 104.7% with a relative standard deviation of 1.0–9.5%. The TRFIA results for the real samples were in good agreement with that obtained by high-performance liquid chromatography analyses. The results indicate that the established TRFIA has potential application for screening paclobutrazol in environmental samples. - Highlights: • The approach to design and synthesize the PBZ hapten was more straightforward. • A rapid and ultrasensitive TRFIA was developed and applied to the screening of PBZ. • The TRFIA for real soil samples showed reliability and high correlation with HPLC. • The PBZ TRFIA showed high sensitivity, simple operation, a wide range of quantitative analyses and no radioactive hazards.

  16. Surface-enhanced Raman scattering detection of silver nanoparticles in environmental and biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Huiyuan [Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States); Xing, Baoshan, E-mail: bx@umass.edu [Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States); Hamlet, Leigh C.; Chica, Andrea [Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States); He, Lili, E-mail: lilihe@foodsci.umass.edu [Department of Food Science, University of Massachusetts, Amherst, MA 01003 (United States)

    2016-06-01

    Growing concerns over the potential release and threat of silver nanoparticles (AgNPs) to environmental and biological systems urge researchers to investigate their fate and behavior. However, current analytical techniques cannot meet the requirements for rapidly, sensitively and reliably probing AgNPs in complex matrices. Surface-enhanced Raman spectroscopy (SERS) has shown great capability for rapid detection of AgNPs based on an indicator molecule that can bind on the AgNP surface. The objective of this study was to exploit SERS to detect AgNPs in environmental and biological samples through optimizing the Raman indicator for SERS. Seven indicator molecules were selected and determined to obtain their SERS signals at optimal concentrations. Among them, 1,2-di(4-pyridyl)ethylene (BPE), crystal violet and ferric dimethyl-dithiocarbamate (ferbam) produced the highest SERS intensities. Further experiments on binding competition between each two of the three candidates showed that ferbam had the highest AgNPs-binding ability. The underlying mechanism lies in the strong binding affinity of ferbam with AgNPs via multiple sulfur atoms. We further validated ferbam to be an effective indicator for SERS detection of as low as 0.1 mg/L AgNPs in genuine surface water and 0.57 mg/L in spinach juice. Moreover, limited interference on SERS detection of AgNPs was found from environmentally relevant inorganic ions, organic matter, inorganic particles, as well as biologically relevant components, demonstrating the ferbam-assisted SERS is an effective and sensitive method to detect AgNPs in complex environmental and biological samples. - Graphical abstract: SERS signal intensity of ferbam indicates the concentration of AgNPs. - Highlights: • Ferbam was found to be the best indicator for SERS detection of AgNPs. • SERS was able to detect AgNPs in both environmental and biological samples. • Major components in the two matrices had limited effect on AgNP detection.

  17. Metagenomic covariation along densely sampled environmental gradients in the Red Sea

    KAUST Repository

    Thompson, Luke R

    2016-07-15

    Oceanic microbial diversity covaries with physicochemical parameters. Temperature, for example, explains approximately half of global variation in surface taxonomic abundance. It is unknown, however, whether covariation patterns hold over narrower parameter gradients and spatial scales, and extending to mesopelagic depths. We collected and sequenced 45 epipelagic and mesopelagic microbial metagenomes on a meridional transect through the eastern Red Sea. We asked which environmental parameters explain the most variation in relative abundances of taxonomic groups, gene ortholog groups, and pathways—at a spatial scale of <2000 km, along narrow but well-defined latitudinal and depth-dependent gradients. We also asked how microbes are adapted to gradients and extremes in irradiance, temperature, salinity, and nutrients, examining the responses of individual gene ortholog groups to these parameters. Functional and taxonomic metrics were equally well explained (75–79%) by environmental parameters. However, only functional and not taxonomic covariation patterns were conserved when comparing with an intruding water mass with different physicochemical properties. Temperature explained the most variation in each metric, followed by nitrate, chlorophyll, phosphate, and salinity. That nitrate explained more variation than phosphate suggested nitrogen limitation, consistent with low surface N:P ratios. Covariation of gene ortholog groups with environmental parameters revealed patterns of functional adaptation to the challenging Red Sea environment: high irradiance, temperature, salinity, and low nutrients. Nutrient-acquisition gene ortholog groups were anti-correlated with concentrations of their respective nutrient species, recapturing trends previously observed across much larger distances and environmental gradients. This dataset of metagenomic covariation along densely sampled environmental gradients includes online data exploration supplements, serving as a community

  18. Real-Time PCR Method for Detection of Salmonella spp. in Environmental Samples.

    Science.gov (United States)

    Kasturi, Kuppuswamy N; Drgon, Tomas

    2017-07-15

    The methods currently used for detecting Salmonella in environmental samples require 2 days to produce results and have limited sensitivity. Here, we describe the development and validation of a real-time PCR Salmonella screening method that produces results in 18 to 24 h. Primers and probes specific to the gene invA , group D, and Salmonella enterica serovar Enteritidis organisms were designed and evaluated for inclusivity and exclusivity using a panel of 329 Salmonella isolates representing 126 serovars and 22 non- Salmonella organisms. The invA - and group D-specific sets identified all the isolates accurately. The PCR method had 100% inclusivity and detected 1 to 2 copies of Salmonella DNA per reaction. Primers specific for Salmonella -differentiating fragment 1 (Sdf-1) in conjunction with the group D set had 100% inclusivity for 32 S Enteritidis isolates and 100% exclusivity for the 297 non-Enteritidis Salmonella isolates. Single-laboratory validation performed on 1,741 environmental samples demonstrated that the PCR method detected 55% more positives than the V itek i mmuno d iagnostic a ssay s ystem (VIDAS) method. The PCR results correlated well with the culture results, and the method did not report any false-negative results. The receiver operating characteristic (ROC) analysis documented excellent agreement between the results from the culture and PCR methods (area under the curve, 0.90; 95% confidence interval of 0.76 to 1.0) confirming the validity of the PCR method. IMPORTANCE This validated PCR method detects 55% more positives for Salmonella in half the time required for the reference method, VIDAS. The validated PCR method will help to strengthen public health efforts through rapid screening of Salmonella spp. in environmental samples.

  19. Assessment of PDMS-water partition coefficients: implications for passive environmental sampling of hydrophobic organic compounds

    Science.gov (United States)

    DiFilippo, Erica L.; Eganhouse, Robert P.

    2010-01-01

    Solid-phase microextraction (SPME) has shown potential as an in situ passive-sampling technique in aquatic environments. The reliability of this method depends upon accurate determination of the partition coefficient between the fiber coating and water (Kf). For some hydrophobic organic compounds (HOCs), Kf values spanning 4 orders of magnitude have been reported for polydimethylsiloxane (PDMS) and water. However, 24% of the published data examined in this review did not pass the criterion for negligible depletion, resulting in questionable Kf values. The range in reported Kf is reduced to just over 2 orders of magnitude for some polychlorinated biphenyls (PCBs) when these questionable values are removed. Other factors that could account for the range in reported Kf, such as fiber-coating thickness and fiber manufacturer, were evaluated and found to be insignificant. In addition to accurate measurement of Kf, an understanding of the impact of environmental variables, such as temperature and ionic strength, on partitioning is essential for application of laboratory-measured Kf values to field samples. To date, few studies have measured Kf for HOCs at conditions other than at 20 degrees or 25 degrees C in distilled water. The available data indicate measurable variations in Kf at different temperatures and different ionic strengths. Therefore, if the appropriate environmental variables are not taken into account, significant error will be introduced into calculated aqueous concentrations using this passive sampling technique. A multiparameter linear solvation energy relationship (LSER) was developed to estimate log Kf in distilled water at 25 degrees C based on published physicochemical parameters. This method provided a good correlation (R2 = 0.94) between measured and predicted log Kf values for several compound classes. Thus, an LSER approach may offer a reliable means of predicting log Kf for HOCs whose experimental log Kf values are presently unavailable. Future

  20. Application of solid phase extraction procedures for rare earth elements determination in environmental samples.

    Science.gov (United States)

    Pyrzynska, Krystyna; Kubiak, Anna; Wysocka, Irena

    2016-07-01

    Determination of rare earth elements in environmental samples requires often pre-concentration and separation step due to a low metal content and high concentration of the interfering matrix components. A solid phase extraction technique with different kind of solid sorbents offers a high enrichment factor, rapid phase separation and the possibility of its combination with various detection techniques used either in on-line or off-line mode. The recent developments in this area published over the last five years are presented and discussed in this paper. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Determination of depleted uranium in environmental samples by gamma-spectroscopic techniques.

    Science.gov (United States)

    Karangelos, D J; Anagnostakis, M J; Hinis, E P; Simopoulos, S E; Zunic, Z S

    2004-01-01

    The military use of depleted uranium initiated the need for an efficient and reliable method to detect and quantify DU contamination in environmental samples. This paper presents such a method, based on the gamma spectroscopic determination of 238U and 235U. The main advantage of this method is that it allows for a direct determination of the U isotope ratio, while requiring little sample preparation and being significantly less labor intensive than methods requiring radiochemical treatment. Furthermore, the fact that the sample preparation is not destructive greatly simplifies control of the quality of measurements. Low energy photons are utilized, using Ge detectors efficient in the low energy region and applying appropriate corrections for self-absorption. Uranium-235 in particular is determined directly from its 185.72 keV photons, after analyzing the 235U-226Ra multiplet. The method presented is applied to soil samples originating from two different target sites, in Southern Yugoslavia and Montenegro. The analysis results are discussed in relation to the natural radioactivity content of the soil at the sampling sites. A mapping algorithm is applied to examine the spatial variability of the DU contamination.

  2. Antimicrobial susceptibility of thermophilic Campylo-bacter spp. isolated from environmental samples

    Directory of Open Access Journals (Sweden)

    Baserisalehi M

    2005-01-01

    Full Text Available Environmental samples were subjected to determine frequency of occurrence of pathogenic campylobacters in the environment. The antimicrobial susceptibility of the isolates was tested to evaluate the level of antibiotic sensitive campylobacters in the environment of investigation. In all, 70 Campylobacter isolates were obtained from water and domestic animal faeces samples using Kapadnis-Baseri device and antimicrobial susceptibility of them was determined by disc diffusion test and E- test. The results indicated that all the isolates of Campylobacter were sensitive to ciprofloxacin and resistant to cefotaxime, cephalexin and ampicillin. Lowest MIC values were observed for ciprofloxacin and gentamicin (2µg/mL and highest MIC values for ampicillin and chloramphinicol (256µg/mL. In general, pathogenic Campylobacter spp. were prevalent in large numbers in the environment, however, they were sensitive to ciprofloxacin.

  3. Automated Clean Chemistry for Bulk Analysis of Environmental Swipe Samples - FY17 Year End Report

    Energy Technology Data Exchange (ETDEWEB)

    Ticknor, Brian W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Metzger, Shalina C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McBay, Eddy H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hexel, Cole R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tevepaugh, Kayron N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bostick, Debra A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-11-30

    Sample preparation methods for mass spectrometry are being automated using commercial-off-the-shelf (COTS) equipment to shorten lengthy and costly manual chemical purification procedures. This development addresses a serious need in the International Atomic Energy Agency’s Network of Analytical Laboratories (IAEA NWAL) to increase efficiency in the Bulk Analysis of Environmental Samples for Safeguards program with a method that allows unattended, overnight operation. In collaboration with Elemental Scientific Inc., the prepFAST-MC2 was designed based on COTS equipment. It was modified for uranium/plutonium separations using renewable columns packed with Eichrom TEVA and UTEVA resins, with a chemical separation method based on the Oak Ridge National Laboratory (ORNL) NWAL chemical procedure. The newly designed prepFAST-SR has had several upgrades compared with the original prepFAST-MC2. Both systems are currently installed in the Ultra-Trace Forensics Science Center at ORNL.

  4. Evaluation of the readsorption of plutonium and americium in dynamic fractionations of environmental solid samples.

    Science.gov (United States)

    Petersen, Roongrat; Hou, Xiaolin; Hansen, Elo Harald

    2008-07-01

    A dynamic extraction system exploiting sequential injection (SI) for sequential extractions incorporating a specially designed extraction column is developed to fractionate radionuclides in environmental solid samples such as soils and sediments. The extraction column can contain up to 5 g of a soil sample, and under optimal operational conditions it does not give rise to creation of back pressure. Attention has been placed on studies of the readsorption problems during sequential extraction using a modified Standards, Measurements and Testing (SM&T) scheme with four-step sequential extractions. The degree of readsorption in dynamic and conventional batch extraction systems is compared and evaluated by using a double-spiking technique. A high degree of readsorption of plutonium and americium (>75%) was observed in both systems, and they also exhibited similar distribution patterns of the two radionuclides. However, the dynamic system is fully automated, eliminates manual separations, significantly reduces the operational time required, and offers detailed kinetic information.

  5. Analytical Methodologies for the Determination of Endocrine Disrupting Compounds in Biological and Environmental Samples

    Directory of Open Access Journals (Sweden)

    Zoraida Sosa-Ferrera

    2013-01-01

    Full Text Available Endocrine-disruptor compounds (EDCs can mimic natural hormones and produce adverse effects in the endocrine functions by interacting with estrogen receptors. EDCs include both natural and synthetic chemicals, such as hormones, personal care products, surfactants, and flame retardants, among others. EDCs are characterised by their ubiquitous presence at trace-level concentrations and their wide diversity. Since the discovery of the adverse effects of these pollutants on wildlife and human health, analytical methods have been developed for their qualitative and quantitative determination. In particular, mass-based analytical methods show excellent sensitivity and precision for their quantification. This paper reviews recently published analytical methodologies for the sample preparation and for the determination of these compounds in different environmental and biological matrices by liquid chromatography coupled with mass spectrometry. The various sample preparation techniques are compared and discussed. In addition, recent developments and advances in this field are presented.

  6. Environmental sampling for respiratory pathogens in Jeddah airport during the 2013 Hajj season.

    Science.gov (United States)

    Memish, Ziad A; Almasri, Malak; Assirri, Abdullah; Al-Shangiti, Ali M; Gray, Gregory C; Lednicky, John A; Yezli, Saber

    2014-12-01

    Respiratory tract infections (RTIs) are common during the Hajj season and are caused by a variety of organisms, which can be transmitted via the air or contaminated surfaces. We conducted a study aimed at sampling the environment in the King Abdul Aziz International (KAAI) Airport, Pilgrims City, Jeddah, during Hajj season to detect respiratory pathogens. Active air sampling was conducted using air biosamplers, and swabs were used to sample frequently touched surfaces. A respiratory multiplex array was used to detect bacterial and viral respiratory pathogens. Of the 58 environmental samples, 8 were positive for at least 1 pathogen. One air sample (1 of 18 samples, 5.5%) tested positive for influenza B virus. Of the 40 surface samples, 7 (17.5%) were positive for pathogens. These were human adenovirus (3 out of 7, 42.8%), human coronavirus OC43/HKU1 (3 out of 7, 42.8%), Haemophilus influenzae (1 out of 7, 14.2%), and Moraxella catarrhalis (1 out of 7, 14.2%). Chair handles were the most commonly contaminated surfaces. The handles of 1 chair were cocontaminated with coronavirus OC43/HKU1 and H influenzae. Respiratory pathogens were detected in the air and on surfaces in the KAAI Airport in Pilgrims City. Larger-scale studies based on our study are warranted to determine the role of the environment in transmission of respiratory pathogens during mass gathering events (eg, Hajj) such that public health preventative measures might be better targeted. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  7. Concordant 241Pu-241Am Dating of Environmental Samples: Results from Forest Fire Ash

    Science.gov (United States)

    Goldstein, S. J.; Oldham, W. J.; Murrell, M. T.; Katzman, D.

    2010-12-01

    We have measured the Pu, 237Np, 241Am, and 151Sm isotopic systematics for a set of forest fire ash samples from various locations in the western U.S. including Montana, Wyoming, Idaho, and New Mexico. The goal of this study is to develop a concordant 241Pu (t1/2 = 14.4 y)-241Am dating method for environmental collections. Environmental samples often contain mixtures of components including global fallout. There are a number of approaches for subtracting the global fallout component for such samples. One approach is to use 242Pu/239Pu as a normalizing isotope ratio in a three-isotope plot, where this ratio for the non-global fallout component can be estimated or assumed to be small. This study investigates a new, complementary method of normalization using the long-lived fission product, 151Sm (t1/2 = 90 y). We find that forest fire ash concentrates actinides and fission products with ~1E10 atoms 239Pu/g and ~1E8 atoms 151Sm/g, allowing us to measure these nuclides by mass spectrometric (MIC-TIMS) and radiometric (liquid scintillation counting) methods. The forest fire ash samples are characterized by a western U.S. regional isotopic signature representing varying mixtures of global fallout with a local component from atmospheric testing of nuclear weapons at the Nevada Test Site (NTS). Our results also show that 151Sm is well correlated with the Pu nuclides in the forest fire ash, suggesting that these nuclides have similar geochemical behavior in the environment. Results of this correlation indicate that the 151Sm/239Pu atom ratio for global fallout is ~0.164, in agreement with an independent estimate of 0.165 based on 137Cs fission yields for atmospheric weapons tests at the NTS. 241Pu-241Am dating of the non-global fallout component in the forest fire ash samples yield ages in the late 1950’s-early 1960’s, consistent with a peak in NTS weapons testing at that time. The age results for this component are in agreement using both 242Pu and 151Sm normalizations

  8. DN/DG Screening of Environmental Swipe Samples: FY2016 Report

    Energy Technology Data Exchange (ETDEWEB)

    Glasgow, David C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Croft, Stephen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Venkataraman, Ramkumar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McElroy, Robert Dennis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Knowles, Justin R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-02-01

    another. That is, the ratio of the yield of a light fission fragment to a heavy fission fragments is isotope specific. Measurement of the ratio of the net full energy peak (FEP) from low/high mass fission products is an elegant way to characterize the fraction of fissile materials present in a mixture. By empirically calibrating the ratio of the net FEP as a function of known concentration of the binary mixture, one can determine the fraction of fissile isotopes in an unknown sample. In the work done in fiscal year (FY) 2016, samples of single fissile material isotopes as well as binary mixtures were irradiated in a well thermalized irradiation field in the HFIR. Delayed neutron counting was performed using the neutron counter at the HFIR Neutron Activation Analysis (NAA) laboratory. Delayed gamma counting was performed using a shielded high purity germanium (HPGe) detector. Delayed neutron decay curve results highlighted the difficulty of distinguishing between U and Pu isotopes, and the need for including the delayed gamma component. Based on delayed gamma spectrometry, twelve ratios of low mass/high fission product gamma ray FEP have been identified as valid candidates. Linearity of the ratios, as a function of 239Pu fraction in 235U+239Pu mixtures, was confirmed for the low mass/high mass candidates that were selected. The DNDG method we are spearheading allows not only the presence of total fissile content to be detected, but whether the material is predominantly U or predominantly Pu, or a mixture. This provides additional SG relevant information.

  9. Net Gain

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

    %) in malaria disease rates following introduction of ITNs. The results of standard clinical trials (randomized, controlled, and using sufficiently large samples) that measured impact on malaria disease in Africa are shown in Table 1. Other studies ...

  10. Determination of Glucocorticoids in UPLC-MS in Environmental Samples from an Occupational Setting

    Directory of Open Access Journals (Sweden)

    Enrico Oddone

    2015-01-01

    Full Text Available Occupational exposures to glucocorticoids are still a neglected issue in some work environments, including pharmaceutical plants. We developed an analytical method to quantify simultaneously 21 glucocorticoids using UPLC coupled with mass spectrometry to provide a basis to carry out environmental monitoring. Samples were taken from air, hand-washing tests, pad-tests and wipe-tests. This paper reports the contents of the analytical methodology, along with the results of this extensive environmental and personal monitoring of glucocorticoids. The method in UPLC-MS turned out to be suitable and effective for the aim of the study. Wipe-test and pad-test desorption was carried out using 50 mL syringes, a simple technique that saves time without adversely affecting analyte recovery. Results showed a widespread environmental pollution due to glucocorticoids. This is of particular concern. Evaluation of the dose absorbed by each worker and identification of a biomarker for occupational exposure will contribute to assessment and prevention of occupational exposure.

  11. Micro-TLC Approach for Fast Screening of Environmental Samples Derived from Surface and Sewage Waters.

    Science.gov (United States)

    Zarzycki, Paweł K; Slączka, Magdalena M; Włodarczyk, Elżbieta; Baran, Michał J

    2013-01-01

    In this work we demonstrated analytical capability of micro-planar (micro-TLC) technique comprising one and two-dimensional (2D) separation modes to generate fingerprints of environmental samples originated from sewage and ecosystems waters. We showed that elaborated separation and detection protocols are complementary to previously invented HPLC method based on temperature-dependent inclusion chromatography and UV-DAD detection. Presented 1D and 2D micro-TLC chromatograms of SPE (solid-phase extraction) extracts were optimized for fast and low-cost screening of water samples collected from lakes and rivers located in the area of Middle Pomerania in northern part of Poland. Moreover, we studied highly organic compounds loaded in the treated and untreated sewage waters obtained from municipal wastewater treatment plant "Jamno" near Koszalin City (Poland). Analyzed environmental samples contained number of substances characterized by polarity range from estetrol to progesterone as well as chlorophyll-related dyes previously isolated and pre-purified by simple SPE protocol involving C18 cartridges. Optimization of micro-TLC separation and quantification protocols of such samples were discussed from the practical point of view using simple separation efficiency criteria including total peaks number, log(product Δ hR F ), signal intensity and peak asymmetry. Outcomes of the presented analytical approach, especially using detection involving direct fluorescence (UV366/Vis) and phosphomolybdic acid (PMA) visualization are compared with UV-DAD HPLC-generated data reported previously. Chemometric investigation based on principal components analysis revealed that SPE extracts separated by micro-TLC and detected under fluorescence and PMA visualization modes can be used for robust sample fingerprinting even after long-term storage of the extracts (up to 4 years) at subambient temperature (-20 °C). Such approach allows characterization of wide range of sample components

  12. Reliability of environmental sampling culture results using the negative binomial intraclass correlation coefficient.

    Science.gov (United States)

    Aly, Sharif S; Zhao, Jianyang; Li, Ben; Jiang, Jiming

    2014-01-01

    The Intraclass Correlation Coefficient (ICC) is commonly used to estimate the similarity between quantitative measures obtained from different sources. Overdispersed data is traditionally transformed so that linear mixed model (LMM) based ICC can be estimated. A common transformation used is the natural logarithm. The reliability of environmental sampling of fecal slurry on freestall pens has been estimated for Mycobacterium avium subsp. paratuberculosis using the natural logarithm transformed culture results. Recently, the negative binomial ICC was defined based on a generalized linear mixed model for negative binomial distributed data. The current study reports on the negative binomial ICC estimate which includes fixed effects using culture results of environmental samples. Simulations using a wide variety of inputs and negative binomial distribution parameters (r; p) showed better performance of the new negative binomial ICC compared to the ICC based on LMM even when negative binomial data was logarithm, and square root transformed. A second comparison that targeted a wider range of ICC values showed that the mean of estimated ICC closely approximated the true ICC.

  13. New developments in the extraction and determination of parabens in cosmetics and environmental samples. A review.

    Science.gov (United States)

    Ocaña-González, Juan Antonio; Villar-Navarro, Mercedes; Ramos-Payán, María; Fernández-Torres, Rut; Bello-López, Miguel Angel

    2015-02-09

    Parabens are a family of synthetic esters of p-hydroxibenzoic acid widely used as preservatives in cosmetics and health-care products, among other daily-use commodities. Recently, their potential endocrine disrupting effects have raised concerns about their safety and their potential effects as emerging pollutants, leading to the regulation of the presence of parabens in commercial products by national and trans-national organizations. Also, this has led to an interest in developing sensible and reliable methods for their determination in environmental samples, cosmetics and health-care products. This paper is a comprehensive up-to-date review of the literature concerning the determination of parabens in environmental samples and cosmetic and health-care products. A brief revision of the literature concerning the traditional determination of parabens (1980-2003) is included, followed by an in-depth revision of the recent developments in both measurement and extraction methods for parabens in the last years (2003-2013). Finally, possible future perspectives in this field are proposed. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. A new selective enrichment procedure for isolating Pasteurella multocida from avian and environmental samples

    Science.gov (United States)

    Moore, M.K.; Cicnjak-Chubbs, L.; Gates, R.J.

    1994-01-01

    A selective enrichment procedure, using two new selective media, was developed to isolate Pasteurella multocida from wild birds and environmental samples. These media were developed by testing 15 selective agents with six isolates of P. multocida from wild avian origin and seven other bacteria representing genera frequently found in environmental and avian samples. The resulting media—Pasteurella multocida selective enrichment broth and Pasteurella multocida selective agar—consisted of a blood agar medium at pH 10 containing gentamicin, potassium tellurite, and amphotericin B. Media were tested to determine: 1) selectivity when attempting isolation from pond water and avian carcasses, 2) sensitivity for detection of low numbers of P. multocida from pure and mixed cultures, 3) host range specificity of the media, and 4) performance compared with standard blood agar. With the new selective enrichment procedure, P. multocida was isolated from inoculated (60 organisms/ml) pond water 84% of the time, whereas when standard blood agar was used, the recovery rate was 0%.

  15. Assessment of DDT levels in selected environmental media and biological samples from Mexico and Central America.

    Science.gov (United States)

    Pérez-Maldonado, Iván N; Trejo, Antonio; Ruepert, Clemens; Jovel, Reyna del Carmen; Méndez, Mónica Patricia; Ferrari, Mirtha; Saballos-Sobalvarro, Emilio; Alexander, Carlos; Yáñez-Estrada, Leticia; Lopez, Dania; Henao, Samuel; Pinto, Emilio R; Díaz-Barriga, Fernando

    2010-03-01

    Taking into account the environmental persistence and the toxicity of DDT, the Pan American Health Organization (PAHO) organized a surveillance program in Mesoamerica which included the detection of residual DDT in environmental (soil) and biological samples (fish tissue and children's blood). This program was carried out in communities from Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. This paper presents the first report of that program. As expected, the results show that the levels for [summation operator] DDT in soil (outdoor or indoor) and fish samples in the majority of the locations studied are below guidelines. However, in some locations, we found children with high concentrations of DDT as in Mexico (mean level 50.2 ng/mL). Furthermore, in some communities and for some matrices, the DDT/DDE quotient is higher than one and this may reflect a recent DDT exposure. Therefore, more efforts are needed to avoid exposure and to prevent the reintroduction of DDT into the region. In this regard it is important to know that under the surveillance of PAHO and with the support of UNEP, a regional program in Mesoamerica for the collection and disposal of DDT and other POPs stockpiles is in progress. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  16. Hypercrosslinked particles for the extraction of sweeteners using dispersive solid-phase extrction from environmental samples.

    Science.gov (United States)

    Lakade, Sameer S; Zhou, Qing; Li, Aimin; Borrull, Francesc; Fontanals, Núria; Marcé, Rosa M

    2017-12-26

    This work presents a new extraction material, namely, Q-100, based on hypercrosslinked magnetic particles, which was tested in dispersive solid-phase extraction for a group of sweeteners from environmental samples. The hypercrosslinked Q-100 magnetic particles had the advantage of suitable pore size distribution and high surface area, and showed good retention behavior towards sweeteners. Different dispersive solid-phase extraction parameters such as amount of magnetic particles or extraction time were optimized. Under optimum conditions, Q-100 showed suitable apparent recovery, ranging in the case of river water sample from 21 to 88% for all the sweeteners, except for alitame (12%). The validated method based on dispersive solid-phase extraction using Q-100 followed by liquid chromatography with tandem mass spectrometry provided good linearity and limits of quantification between 0.01 and 0.1 μg L -1 . The method was applied to analyze samples from river water and effluent wastewater, and four sweeteners (acesulfame, saccharin, cyclamate and sucralose) were found in both types of sample. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Intercomparison of laboratory analyses of radionuclides in environmental samples, 2004-2005[Radioecology

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Sven P. [Risoe National Lab., Roskilde (Denmark)

    2006-04-15

    An intercomparison exercise of radionuclides in environmental samples and foodstuffs has been carried out. A total of 821 analytical results were received from 38 laboratories. Half of the laboratories are from the Nordic countries and the other half from Estonia, Latvia, Lithuania, Poland, Russia and Hungary. The concentrations of radionuclides in the samples were unknown for what reason the evaluation was based on comparison with median values. However, one of the samples (soil) was a certified reference material (IAEA-375), and for this sample good agreement was found between the median values and the certified values. The comparison shows generally good agreement between laboratories with some exceptions. Results for which the agreement is not good include {sup 90}Sr, {sup 241}Am, {sup 210}Pb and total alpha and total beta. Less than half of the participants meet the evaluation criteria concerning these results. For these analyses there seems to be a particular need for improved analytical quality and testing of the results in international intercomparison exercises. (au)

  18. Detection limits of Legionella pneumophila in environmental samples after co-culture with Acanthamoeba polyphaga

    Science.gov (United States)

    2013-01-01

    Background The efficiency of recovery and the detection limit of Legionella after co-culture with Acanthamoeba polyphaga are not known and so far no investigations have been carried out to determine the efficiency of the recovery of Legionella spp. by co-culture and compare it with that of conventional culturing methods. This study aimed to assess the detection limits of co-culture compared to culture for Legionella pneumophila in compost and air samples. Compost and air samples were spiked with known concentrations of L. pneumophila. Direct culturing and co-culture with amoebae were used in parallel to isolate L. pneumophila and recovery standard curves for both methods were produced for each sample. Results The co-culture proved to be more sensitive than the reference method, detecting 102-103 L. pneumophila cells in 1 g of spiked compost or 1 m3 of spiked air, as compared to 105-106 cells in 1 g of spiked compost and 1 m3 of spiked air. Conclusions Co-culture with amoebae is a useful, sensitive and reliable technique to enrich L. pneumophila in environmental samples that contain only low amounts of bacterial cells. PMID:23442526

  19. [Isolation of Sporothrix pallida complex in clinical and environmental samples from Chile].

    Science.gov (United States)

    Cruz Choappa, Rodrigo M; Vieille Oyarzo, Peggy I; Carvajal Silva, Laura C

    2014-01-01

    The isolation of S. pallida complex from medical samples and home garden soil of a patient in Chile is here in reported. Fungi of the Sporothrix schenckii complex can cause various infections. In Chile, the medical and environmental isolates of these this complex are rare. The aim of this study was to identify an unusual agent in a case of onychomycosis and to detect its presence in the patient's home garden. For this purpose, clinical samples were obtained by scraping the patient's subungueal first right toe nail as well as by taking soil samples from different areas of her home garden. Species identification was performed by morphophysiology and one of the strains isolated from the patient's toe nail was sent to CBS for molecular confirmation (14.062). S. pallida complex was identified both from the patient's toe nail and samples taken from her home garden. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  20. Simple Sensitive Spectrophotometric Determination of Vanadium in Biological and Environmental Samples

    Directory of Open Access Journals (Sweden)

    B. Krishna Priya

    2006-01-01

    Full Text Available Novel, rapid, highly sensitive and selective spectrophotometric method for the determination of traces of vanadium (V in environmental and biological samples, pharmaceutical and steel samples was studied. The method is based on oxidation of 2,4- dinitro phenyl hydrazine(2,4-DNPH by vanadium (V followed by coupling reaction with N-(1-naphthalene-1-ylethane-1,2-diamine-dihydrochloride (NEDA in acidic medium to give red colored derivative or on oxidation of 4-Amino Pyridine by vanadium (V followed by coupling reaction with NEDA in basic medium to give pink colored derivative. The red colored derivative having an λmax 495 nm which is stable for 8 days and the pink colored derivative with 525 nm is stable for more than 7 days at 350C. Beer's law is obeyed for vanadium (V in the concentration range of 0.02 - 3.5 μg mL–1 (red derivative and 0.03 – 4.5 μg mL–1 (pink derivative at the wave length of maximum absorption. The optimum reaction conditions and other analytical parameters were investigated to enhance the sensitivity of the present method. The detailed study of various interferences made the method more selective. The proposed method was successfully applied to the analysis of vanadium in natural water samples, plant material, soil samples, synthetic mixtures, pharmaceutical samples and biological samples. The results obtained were agreed with the reported methods at the 95 % confidence level. The performance of proposed method was evaluated in terms of Student's t-test and Variance ratio f-test which indicates the significance of proposed method over reported method.

  1. DEP-On-Go for Simultaneous Sensing of Multiple Heavy Metals Pollutants in Environmental Samples

    Directory of Open Access Journals (Sweden)

    Madhu Biyani

    2016-12-01

    Full Text Available We describe a simple and affordable “Disposable electrode printed (DEP-On-Go” sensing platform for the rapid on-site monitoring of trace heavy metal pollutants in environmental samples for early warning by developing a mobile electrochemical device composed of palm-sized potentiostat and disposable unmodified screen-printed electrode chips. We present the analytical performance of our device for the sensitive detection of major heavy metal ions, namely, mercury, cadmium, lead, arsenic, zinc, and copper with detection limits of 1.5, 2.6, 4.0, 5.0, 14.4, and, 15.5 μg·L−1, respectively. Importantly, the utility of this device is extended to detect multiple heavy metals simultaneously with well-defined voltammograms and similar sensitivity. Finally, “DEP-On-Go” was successfully applied to detect heavy metals in real environmental samples from groundwater, tap water, house dust, soil, and industry-processed rice and noodle foods. We evaluated the efficiency of this system with a linear correlation through inductively coupled plasma mass spectrometry, and the results suggested that this system can be reliable for on-site screening purposes. On-field applications using real samples of groundwater for drinking in the northern parts of India support the easy-to-detect, low-cost (<1 USD, rapid (within 5 min, and reliable detection limit (ppb levels performance of our device for the on-site detection and monitoring of multiple heavy metals in resource-limited settings.

  2. Methodologies for the Extraction of Phenolic Compounds from Environmental Samples: New Approaches

    Directory of Open Access Journals (Sweden)

    Cristina Mahugo Santana

    2009-01-01

    Full Text Available Phenolic derivatives are among the most important contaminants present in the environment. These compounds are used in several industrial processes to manufacture chemicals such as pesticides, explosives, drugs and dyes. They also are used in the bleaching process of paper manufacturing. Apart from these sources, phenolic compounds have substantial applications in agriculture as herbicides, insecticides and fungicides. However, phenolic compounds are not only generated by human activity, but they are also formed naturally, e.g., during the decomposition of leaves or wood. As a result of these applications, they are found in soils and sediments and this often leads to wastewater and ground water contamination. Owing to their high toxicity and persistence in the environment, both, the US Environmental Protection Agency (EPA and the European Union have included some of them in their lists of priority pollutants. Current standard methods of phenolic compounds analysis in water samples are based on liquid–liquid extraction (LLE while Soxhlet extraction is the most used technique for isolating phenols from solid matrices. However, these techniques require extensive cleanup procedures that are time-intensive and involve expensive and hazardous organic solvents, which are undesirable for health and disposal reasons. In the last years, the use of news methodologies such as solid-phase extraction (SPE and solid-phase microextraction (SPME have increased for the extraction of phenolic compounds from liquid samples. In the case of solid samples, microwave assisted extraction (MAE is demonstrated to be an efficient technique for the extraction of these compounds. In this work we review the developed methods in the extraction and determination of phenolic derivatives in different types of environmental matrices such as water, sediments and soils. Moreover, we present the new approach in the use of micellar media coupled with SPME process for the

  3. Methodologies for the extraction of phenolic compounds from environmental samples: new approaches.

    Science.gov (United States)

    Mahugo Santana, Cristina; Sosa Ferrera, Zoraida; Esther Torres Padrón, M; Juan Santana Rodríguez, José

    2009-01-09

    Phenolic derivatives are among the most important contaminants present in the environment. These compounds are used in several industrial processes to manufacture chemicals such as pesticides, explosives, drugs and dyes. They also are used in the bleaching process of paper manufacturing. Apart from these sources, phenolic compounds have substantial applications in agriculture as herbicides, insecticides and fungicides. However, phenolic compounds are not only generated by human activity, but they are also formed naturally, e.g., during the decomposition of leaves or wood. As a result of these applications, they are found in soils and sediments and this often leads to wastewater and ground water contamination. Owing to their high toxicity and persistence in the environment, both, the US Environmental Protection Agency (EPA) and the European Union have included some of them in their lists of priority pollutants. Current standard methods of phenolic compounds analysis in water samples are based on liquid-liquid extraction (LLE) while Soxhlet extraction is the most used technique for isolating phenols from solid matrices. However, these techniques require extensive cleanup procedures that are time-intensive and involve expensive and hazardous organic solvents, which are undesirable for health and disposal reasons. In the last years, the use of news methodologies such as solid-phase extraction (SPE) and solid-phase microextraction (SPME) have increased for the extraction of phenolic compounds from liquid samples. In the case of solid samples, microwave assisted extraction (MAE) is demonstrated to be an efficient technique for the extraction of these compounds. In this work we review the developed methods in the extraction and determination of phenolic derivatives in different types of environmental matrices such as water, sediments and soils. Moreover, we present the new approach in the use of micellar media coupled with SPME process for the extraction of phenolic

  4. Co-assortment in integron-associated gene cassette assemblages in environmental DNA samples

    Directory of Open Access Journals (Sweden)

    Michael Carolyn A

    2010-08-01

    Full Text Available Abstract Background It has been shown that integron-associated gene cassettes exist largely in tandem arrays of variable size, ranging from antibiotic resistance arrays of three to five cassettes up to arrays of more than 100 cassettes associated with the vibrios. Further, the ecology of the integron/gene cassette system has been investigated by showing that very many different cassettes are present in even small environmental samples. In this study, we seek to extend the ecological perspective on the integron/gene cassette system by investigating the way in which this diverse cassette metagenome is apportioned amongst prokaryote lineages in a natural environment. Results We used a combination of PCR-based techniques applied to environmental DNA samples and ecological analytical techniques to establish co-assortment within cassette populations, then establishing the relationship between this co-assortment and genomic structures. We then assessed the distribution of gene cassettes within the environment and found that the majority of gene cassettes existed in large co-assorting groups. Conclusions Our results suggested that the gene cassette diversity of a relatively pristine sampling environment was structured into co-assorting groups, predominantly containing large numbers of cassettes per group. These co-assorting groups consisted of different gene cassettes in stoichiometric relationship. Conservatively, we then attributed co-assorting cassettes to the gene cassette complements of single prokaryote lineages and by implication, to large integron-associated arrays. The prevalence of large arrays in the environment raises new questions about the assembly, maintenance and utility of large cassette arrays in prokaryote populations.

  5. Co-assortment in integron-associated gene cassette assemblages in environmental DNA samples.

    Science.gov (United States)

    Michael, Carolyn A; Andrew, Nigel R

    2010-08-10

    It has been shown that integron-associated gene cassettes exist largely in tandem arrays of variable size, ranging from antibiotic resistance arrays of three to five cassettes up to arrays of more than 100 cassettes associated with the vibrios. Further, the ecology of the integron/gene cassette system has been investigated by showing that very many different cassettes are present in even small environmental samples. In this study, we seek to extend the ecological perspective on the integron/gene cassette system by investigating the way in which this diverse cassette metagenome is apportioned amongst prokaryote lineages in a natural environment. We used a combination of PCR-based techniques applied to environmental DNA samples and ecological analytical techniques to establish co-assortment within cassette populations, then establishing the relationship between this co-assortment and genomic structures. We then assessed the distribution of gene cassettes within the environment and found that the majority of gene cassettes existed in large co-assorting groups. Our results suggested that the gene cassette diversity of a relatively pristine sampling environment was structured into co-assorting groups, predominantly containing large numbers of cassettes per group. These co-assorting groups consisted of different gene cassettes in stoichiometric relationship. Conservatively, we then attributed co-assorting cassettes to the gene cassette complements of single prokaryote lineages and by implication, to large integron-associated arrays. The prevalence of large arrays in the environment raises new questions about the assembly, maintenance and utility of large cassette arrays in prokaryote populations.

  6. Detection of a diverse marine fish fauna using environmental DNA from seawater samples.

    Science.gov (United States)

    Thomsen, Philip Francis; Kielgast, Jos; Iversen, Lars Lønsmann; Møller, Peter Rask; Rasmussen, Morten; Willerslev, Eske

    2012-01-01

    Marine ecosystems worldwide are under threat with many fish species and populations suffering from human over-exploitation. This is greatly impacting global biodiversity, economy and human health. Intriguingly, marine fish are largely surveyed using selective and invasive methods, which are mostly limited to commercial species, and restricted to particular areas with favourable conditions. Furthermore, misidentification of species represents a major problem. Here, we investigate the potential of using metabarcoding of environmental DNA (eDNA) obtained directly from seawater samples to account for marine fish biodiversity. This eDNA approach has recently been used successfully in freshwater environments, but never in marine settings. We isolate eDNA from ½-litre seawater samples collected in a temperate marine ecosystem in Denmark. Using next-generation DNA sequencing of PCR amplicons, we obtain eDNA from 15 different fish species, including both important consumption species, as well as species rarely or never recorded by conventional monitoring. We also detect eDNA from a rare vagrant species in the area; European pilchard (Sardina pilchardus). Additionally, we detect four bird species. Records in national databases confirmed the occurrence of all detected species. To investigate the efficiency of the eDNA approach, we compared its performance with 9 methods conventionally used in marine fish surveys. Promisingly, eDNA covered the fish diversity better than or equal to any of the applied conventional methods. Our study demonstrates that even small samples of seawater contain eDNA from a wide range of local fish species. Finally, in order to examine the potential dispersal of eDNA in oceans, we performed an experiment addressing eDNA degradation in seawater, which shows that even small (100-bp) eDNA fragments degrades beyond detectability within days. Although further studies are needed to validate the eDNA approach in varying environmental conditions, our

  7. Parabens in 24 h urine samples of the German Environmental Specimen Bank from 1995 to 2012.

    Science.gov (United States)

    Moos, Rebecca K; Koch, Holger M; Angerer, Jürgen; Apel, Petra; Schröter-Kermani, Christa; Brüning, Thomas; Kolossa-Gehring, Marike

    2015-10-01

    Parabens are widely used as antimicrobial preservatives in personal care and consumer products, food and pharmaceuticals. Due to their ubiquity, humans are constantly exposed to these chemicals. We assessed exposure to nine parabens (methyl-, ethyl-, n- and iso-propyl-, n- and iso-butyl-, benzyl-, pentyl- and heptyl paraben) in the German population from 1995 to 2012 based on 660 24h urine samples from the German Environmental Specimen Bank (ESB) using on-line HPLC coupled to isotope dilution tandem mass spectrometry. The limit of quantification (LOQ) was 0.5 μg/L for all parabens. We detected methyl-, ethyl- and n-propyl paraben in 79-99% of samples, followed by n-butyl paraben in 40% of samples. We infrequently detected iso-butyl-, iso-propyl- and benzyl paraben in 24%, 4% and 1.4% of samples, respectively. Urinary concentrations were highest for methyl paraben (median 39.8 μg/L; 95th percentile 319 μg/L) followed by n-propyl paraben (4.8 μg/L; 95th percentile 74.0 μg/L) and ethyl paraben (2.1 μg/L; 95th percentile 39.1 μg/L). Women had significantly higher urinary levels for all parabens than men, except for benzyl paraben. Samples from the ESB revealed that over the investigation period of nearly 20 years urinary paraben levels remained surprisingly constant; only methyl paraben had a significant increase, for both men and women. We found strong correlations between methyl- and n-propyl paraben and between n- and iso-butyl paraben. These results indicate that parabens are used in combination and arise from common sources of exposure. Urinary excretion factors are needed to extrapolate from individual urinary concentrations to actual doses. Copyright © 2015 Elsevier GmbH. All rights reserved.

  8. Comparison of ten different DNA extraction procedures with respect to their suitability for environmental samples.

    Science.gov (United States)

    Kuhn, Ramona; Böllmann, Jörg; Krahl, Kathrin; Bryant, Isaac Mbir; Martienssen, Marion

    2017-12-01

    DNA extraction for molecular biological applications usually requires target optimized extraction procedures depending on the origin of the samples. For environmental samples, a range of different procedures has been developed. We compared the applicability and efficiency of ten selected DNA extraction methods published in recent literature using four different environmental samples namely: activated sludge from a domestic wastewater treatment plant, river sediment, anaerobic digestion sludge and nitrifying enrichment culture. We assessed the suitability of the extraction procedures based on both DNA yield and quality. DNA quantification was performed by both ultra violet (UV) spectrophotometry and fluorescence spectrophotometry after staining with PicoGreen. In our study, DNA yields based on UV measurement were overestimated in most cases while DNA yields from fluorescence measurements correlated well with the sample load on agarose gels of crude DNA. The quality of the DNA extracts was determined by gel electrophoresis of crude DNA and PCR products from 16S rDNA with the universal primer set 27f/1525r. It was observed that gel electrophoresis of crude DNA was not always suitable to evaluate DNA integrity and purity since interfering background substances (e.g. humic substances) were not visible. Therefore, we strongly recommend examining the DNA quality of both crude DNA and 16S rDNA PCR products by gel electrophoresis when a new extraction method is established. Summarizing, we found four out of ten extraction procedures being applicable to all tested samples without noticeable restrictions. The procedure G (according to the standard method 432_10401 of the Lower Saxony State Office for Consumer Protection and Food Safety) had the broadest application range over procedure J (published by Wilson, 2001). These were followed by procedures F (Singka et al., 2012) and A (Bourrain et al., 1999). All four extraction procedures delivered reliable and reproducible crude

  9. Towards a Mobile Ecogenomic sensor: the Third Generation Environmental Sample Processor (3G-ESP).

    Science.gov (United States)

    Birch, J. M.; Pargett, D.; Jensen, S.; Roman, B.; Preston, C. M.; Ussler, W.; Yamahara, K.; Marin, R., III; Hobson, B.; Zhang, Y.; Ryan, J. P.; Scholin, C. A.

    2016-02-01

    Researchers are increasingly using one or more autonomous platforms to characterize ocean processes that change in both space and time. Conceptually, studying processes that change quickly both spatially and temporally seems relatively straightforward. One needs to sample in many locations synoptically over time, or follow a coherent water mass and sample it repeatedly. However, implementing either approach presents many challenges. For example, acquiring samples over days to weeks far from shore, without human intervention, requires multiple systems to work together seamlessly, and the level of autonomy, navigation and communications needed to conduct the work exposes the complexity of these requirements. We are addressing these challenges by developing a new generation of robotic systems that are primarily aimed at studies of microbial-mediated processes. As a step towards realizing this new capability, we have taken lessons learned from our second-generation Environmental Sample Processor (2G-ESP), a robotic microbiology "lab-in-a-can" and have re-engineered the system for use on a Tethys-class Long Range AUV (LRAUV). The new instrument is called the third-generation ESP (3G-ESP), and its integration with the LRAUV provides mobility and a persistent presence not seen before in microbial oceanography. The 3G-ESP autonomously filters a water sample and then either preserves that material for eventual return to a laboratory, or processes the sample in real-time for further downstream molecular analytical analyses. The 3G ESP modularizes hardware needed for the collection and preparation of a sample from subsequent molecular analyses by the use of self-contained "cartridges". Cartridges currently come in two forms: one for the preservation of a sample, and the other for onboard homogenization and handoff for downstream processing via one or more analytical devices. The 3G-ESP is designed as a stand-alone instrument, and thus could be deployed on a variety of

  10. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, GROUNDWATER SAMPLING TECHNOLOGIES, GEOPROBE INC, MECHANICAL BLADDER PUMP MODEL MP470

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) design efficient processes for conducting has created the Environmental Technology perfofl1lance tests of innovative technologies. Verification Program (E TV) to facilitate the deployment of innovative or improved environmental techn...

  11. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, GROUNDWATER SAMPLING TECHNOLOGIES, GEOLOG, INC., MICRO-FLO BLADDER PUMP MODEL 57400

    Science.gov (United States)

    The U.S. Environmental Protection Agency has created the Environmental Technology Verification Program to facilitate the deployment of innovative or improved environmental technologies through performance verification and dissemination of information. The goal of the ETV Program...

  12. Magnetic Study on Environmental Samples from Guadalajara Mexico for Monitoring of Atmospheric Pollution

    Science.gov (United States)

    Aguilar, B.; Cejudo, R.; Bogalo, M. F.; Rosas-Elguera, J.; Quintana, P.; Bautista, F.; Gogichaishvili, A.; Morales, J.

    2013-05-01

    Guadalajara is the second bigger city in Mexico, catalogued as critical zone because of atmospheric pollution levels. The magnetic methodology has been largely used as an alternative way to evaluate the pollution levels as well as identify the critical points in a given area. In this work, results from chemical analyses and magnetic measurements are presented in order to show the correlation between magnetic signal and the pollution level. We analyzed three kinds of environmental samples: urban soils, urban dust and leaves from ficus benjamina. Samples were taken in 30 sites distributed along a main avenue and two secondary avenues, including three points with very poor traffic influence. We determined a ferromagnetic carrier in most of samples, magnetite probably, since the Tc calculated from the thermomagnetic curves is around 580 °C. The magnetic susceptibility (Xlf) as well as the Saturation Isothermal Remanent Magnetization (SIRM) correlate well with the heavy metals content, specially Pb in urban dusts. These results allowed us to identify the most affected points, by vehicular traffic and industrial emissions. Furthermore, the values obtained for these magnetic parameters are above of those found in other studies for polluted cities in Europe and Asia.

  13. [Spina bifida occulta associated with environmental arsenic exposure in a prehispanic sample from northern Chile].

    Science.gov (United States)

    Silva-Pinto, Verónica; Arriaza, Bernardo; Standen, Vivien

    2010-04-01

    The Camarones River Valley, located in the extreme north of Chile, is characterized by high environmental arsenic levels and an arid desert. It has been inhabited by humans for the past 7,000 years. Evidence exists for chronic arsenic poisoning in both prehispanic and present populations residing in the area. Chronic arsenic exposure causes multi-systemic problems and can induce congenital malformations, in particular neural tube development defects such as spina bifida. To study the prevalence of spina bifida among prehispanic mummies of the area. One hundred and twenty prehistoric adult individuals were analyzed for evidence of spina bifda occulta of the sacrum in skeletal samples from the sites of Camarones 8, Camarones 9, Azapa 140 and Lluta 54, held in repository at the Museo Universidad de Tarapacá de Arica- San Miguel de Azapa. A diagnosis was considered positive when at least S1, S2 or S3 were affected. As controls, mummies of individuals that resided in Lluta and Azapa valley, with a low arsenic exposure, were analyzed. The frequency of spina bifida occulta among samples from the Camarones coast and Lluta and Azapa Valley were 13.5 and 2.4% respectively. Considering these were contemporaneous samples, and are believed to have had no other differences in diet or other factors, the differential exposures to arsenic could have produced the observed differences in spina bifida frequencies.

  14. Extractive spectrophotometric method for the determination of carbaryl in environmental samples

    Directory of Open Access Journals (Sweden)

    D. K. Sharma

    2015-07-01

    Full Text Available In the view of the potential hazards associated with the widespread use of carbaryl insecticide, a new simple extractive spectrophotometric method has been developed for its determination in environmental samples viz. soil, water and foodstuffs for its safer and more effective use. The proposed method is based on the microwave assisted alkaline hydrolysis of the insecticide to methylamine. The later is measured as methyl isobutyl ketone (MIBK extractable yellow nickel(II-methyldithiocarbamate complex at 380 nm through the reaction with carbon disulfide and nickel(II acetate. The insecticide can be determined in the linearity range from 2.01 to 60.3 µg mL-1 with a correlation coefficient of 0.996. The method has been applied to the analysis of carbaryl in its commercial formulation and its recovery from vegetable and water samples for monitoring health hazards. Recoveries of the insecticide from vegetables and spiked water samples were good, ranging from 87.6-92.8%, with RSDs ranging from 0.54-1.02%. The method has also been validated for investigating the sorption of carbaryl on five soils with different characteristics to evaluate its leaching behaviour which is a measure of ground and surface water contamination. The leaching potential of the insecticide in terms of groundwater ubiquity score (GUS has values in the range 1.8-2.2 classifying it as transition leacher hence it has potential to contaminate groundwater.

  15. Estimating occupancy and abundance of stream amphibians using environmental DNA from filtered water samples

    Science.gov (United States)

    Pilliod, David S.; Goldberg, Caren S.; Arkle, Robert S.; Waits, Lisette P.

    2013-01-01

    Environmental DNA (eDNA) methods for detecting aquatic species are advancing rapidly, but with little evaluation of field protocols or precision of resulting estimates. We compared sampling results from traditional field methods with eDNA methods for two amphibians in 13 streams in central Idaho, USA. We also evaluated three water collection protocols and the influence of sampling location, time of day, and distance from animals on eDNA concentration in the water. We found no difference in detection or amount of eDNA among water collection protocols. eDNA methods had slightly higher detection rates than traditional field methods, particularly when species occurred at low densities. eDNA concentration was positively related to field-measured density, biomass, and proportion of transects occupied. Precision of eDNA-based abundance estimates increased with the amount of eDNA in the water and the number of replicate subsamples collected. eDNA concentration did not vary significantly with sample location in the stream, time of day, or distance downstream from animals. Our results further advance the implementation of eDNA methods for monitoring aquatic vertebrates in stream habitats.

  16. Use of a Filter Cartridge for Filtration of Water Samples and Extraction of Environmental DNA.

    Science.gov (United States)

    Miya, Masaki; Minamoto, Toshifumi; Yamanaka, Hiroki; Oka, Shin-Ichiro; Sato, Keiichi; Yamamoto, Satoshi; Sado, Tetsuya; Doi, Hideyuki

    2016-11-25

    Recent studies demonstrated the use of environmental DNA (eDNA) from fishes to be appropriate as a non-invasive monitoring tool. Most of these studies employed disk fiber filters to collect eDNA from water samples, although a number of microbial studies in aquatic environments have employed filter cartridges, because the cartridge has the advantage of accommodating large water volumes and of overall ease of use. Here we provide a protocol for filtration of water samples using the filter cartridge and extraction of eDNA from the filter without having to cut open the housing. The main portions of this protocol consists of 1) filtration of water samples (water volumes ≤4 L or >4 L); (2) extraction of DNA on the filter using a roller shaker placed in a preheated incubator; and (3) purification of DNA using a commercial kit. With the use of this and previously-used protocols, we perform metabarcoding analysis of eDNA taken from a huge aquarium tank (7,500 m3) with known species composition, and show the number of detected species per library from the two protocols as the representative results. This protocol has been developed for metabarcoding eDNA from fishes, but is also applicable to eDNA from other organisms.

  17. Sampling

    CERN Document Server

    Thompson, Steven K

    2012-01-01

    Praise for the Second Edition "This book has never had a competitor. It is the only book that takes a broad approach to sampling . . . any good personal statistics library should include a copy of this book." —Technometrics "Well-written . . . an excellent book on an important subject. Highly recommended." —Choice "An ideal reference for scientific researchers and other professionals who use sampling." —Zentralblatt Math Features new developments in the field combined with all aspects of obtaining, interpreting, and using sample data Sampling provides an up-to-date treat

  18. An Improved Method for High Quality Metagenomics DNA Extraction from Human and Environmental Samples

    DEFF Research Database (Denmark)

    Bag, Satyabrata; Saha, Bipasa; Mehta, Ojasvi

    2016-01-01

    and quantity from culturable and uncultured microbial species living in that environment. Proper lysis of heterogeneous community microbial cells without damaging their genomes is a major challenge. In this study, we have developed an improved method for extraction of community DNA from different environmental......To explore the natural microbial community of any ecosystems by high-resolution molecular approaches including next generation sequencing, it is extremely important to develop a sensitive and reproducible DNA extraction method that facilitate isolation of microbial DNA of sufficient purity...... and human origin samples. We introduced a combination of physical, chemical and mechanical lysis methods for proper lysis of microbial inhabitants. The community microbial DNA was precipitated by using salt and organic solvent. Both the quality and quantity of isolated DNA was compared with the existing...

  19. Studies of human and veterinary drugs' fate in environmental solid samples--analytical problems.

    Science.gov (United States)

    Wilga, Joanna; Kot-Wasik, Agata; Namieśnik, Jacek

    2008-08-01

    The improvement of medical care worldwide is one of the reasons for the increasing production of pharmaceutical products. Human medicines are affordable to a greater proportion of the world's population. But a significant amount of used pharmaceuticals can create problems--accessibility to high volume production pharmaceuticals contributes to an increased contamination in the environment and the possibility of adverse effects on humans and animals. Many of these substances and their metabolites end up in the soil, sediments, and sludge. Knowledge regarding the environmental occurrence of pharmaceutical products is increasing, but information in the peer-reviewed literature regarding the fate and effects of most pharmaceuticals is limited. One of the reasons for this lack of data is that, until now, there have been few analytical methods capable of detecting these compounds at the low levels, which might be expected in the environment. This review article covers recent developments in the analysis of pharmaceuticals in environmental solid matrices (including soil, sediments, and sludge). We will report applications of different solid sample extraction methods, and current advances in liquid chromatography coupled with mass spectrometry for detection and identification of selected drugs in sludge, soils, manure, and sediments.

  20. Development of immunoaffinity solid phase microextraction rods for analysis of three estrogens in environmental water samples.

    Science.gov (United States)

    Wang, Cuicui; Yang, Linyan; Li, Na; Zhang, Xinda; Guo, Yongze; Li, Cun

    2017-09-01

    In this study, immunoaffinity solid phase microextraction (SPME) rods were developed for the analysis of diethylstilbestrol (DES), hexestrol (HES) and dienestrol (DIS) followed by ultra high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). This immunoaffinity SPME device was built with three stainless steel rods bundled together as one and modified with porous silicate particles. As an extraction sorbent, antibody immobilization approach was employed based on the covalent attachment of the anti-diethylstilbestrol monoclonal antibody (mAb) onto the rods. The immunoaffinity SPME rod was characterized and confirmed by scanning electron microscopy and X-ray photoelectron spectroscopy analysis. The porous network showed a very large active surface area and significantly increased the adsorption capacity which can reach 49.6pmol/cm(2). Moreover, the immunoaffinity sorbent showed good sturdiness at least 10 times with stable extraction performance. Once the main experimental parameters were optimized, the method was used to detect DES, HES and DIS in environmental water samples. The limits of detection for the three estrogens were 0.05-0.15ng/mL, and the limits of quantification was 0.5ng/mL. The average recoveries ranged from 34.2 to 62.7% were achieved with good intra-day and inter-day precision ranging from 7.8 to 12.7% and from 8.2 to 13.5% respectively. The newly developed immunoaffinity SPME showed high adsorption capacity, good sensitivity and reproducibility and was successfully applied to the analysis of DES, HES and DIS in environmental water samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Magnetically responsive polycaprolactone nanoparticles for progesterone screening in biological and environmental samples using gas chromatography.

    Science.gov (United States)

    Es'haghi, Zarrin; Nezhadali, Azizollah; Khatibi, Aram-Dokht

    2016-08-01

    A new Fe3O4/poly(є-caprolactone) (PCL) magnetite nanocomposite was fabricated and used as a sorbent for magnetically mediated PCL microspheres solid-phase extraction (MM-PCL-SPE) followed by gas chromatography-flame ionization detection (GC-FID) for monitoring of progesterone (PGN) hormone in biological and environmental matrices, namely blood serum, tap water, urine, and hospital wastewater. The nanomagnetite core of the sorbent was synthesized by a co-precipitation method. Magnetic nanoparticles (MNPs) were then microencapsulated with PCL microspheres using emulsion polymerization. The nanocomposite was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The magnetite sorbent can be effectively dispersed in aqueous solution and attracted to an external magnetic field. The MM-PCL-SPE process for PGN assay involved (a) dispersion of the sorbent in the donor phase aqueous solution with sonication, (b) exposure to a magnetic field to collect sorbent that had adsorbed the analyte, and (c) solvent desorption of extracted PGN for GC-FID analysis. The work demonstrates the usefulness of MM-PCL-SPE in the rapid and sensitive monitoring of trace amounts of PGN in real samples. The limit of detection (LOD) and limit of quantification (LOQ) were 1.00 and 3.30 ng/mL, respectively. The relative recoveries in real samples were adequate. Linearity was observed over a wide range of 2.2-10,000.0 ng/mL in aqueous media and urine and 0.01-70.0 μg/mL in blood serum. Graphical Abstract In this research new Fe3O4/poly(є-caprolactone) (PCL) magnetite microspheres were developed as an efficient sorbent for solid-phase extraction of progesterone hormone in biological and environmental matrices.

  2. Species and Strain-specific Typing of Cryptosporidium Parasites in Clinical and Environmental Samples

    Directory of Open Access Journals (Sweden)

    Xiao Lihua

    1998-01-01

    Full Text Available Cryptosporidiosis has recently attracted attention as an emerging waterborne and foodborne disease as well as an opportunistic infection in HIV infected individuals. The lack of genetic information, however, has resulted in confusion in the taxonomy of Cryptosporidium parasites and in the development of molecular tools for the identification and typing of oocysts in environmental samples. Phylogenetic analysis of the small subunit ribosomal RNA (SSU rRNA gene has shown that the genus Cryptosporidium is comprised of several distinct species. Our data show the presence of at least four species: C. parvum, C. muris, C. baileyi and C. serpentis (C. meleagridis, C. nasorum and C. felis were not studied. Within each species, there is some sequence variation. Thus, various genotypes (genotype 1, genotype 2, guinea pig genotype, monkey genotype and koala genotype, etc. of C. parvum differ from each other in six regions of the SSU rRNA gene. Information on polymorphism in Cryptosporidium parasites has been used in the development of species and strain-specific diagnostic tools. Use of these tools in the characterization of oocysts various samples indicates that C. parvum genotype 1 is the strain responsible for most human Cryptosporidium infections. In contrast, genotype 2 is probably the major source for environmental contamination of environment, and has been found in most oysters examined from Chesapeake Bay that serve as biologic monitors of surface water. Parasites of Cryptosporidium species other than C. parvum have not been detected in HIV+ individuals, indicating that the disease in humans is caused only by C. parvum.

  3. Measurement of extremely (2) H-enriched water samples by laser spectrometry: application to batch electrolytic concentration of environmental tritium samples.

    Science.gov (United States)

    Wassenaar, L I; Kumar, B; Douence, C; Belachew, D L; Aggarwal, P K

    2016-02-15

    Natural water samples artificially or experimentally enriched in deuterium ((2) H) at concentrations up to 10,000 ppm are required for various medical, environmental and hydrological tracer applications, but are difficult to measure using conventional stable isotope ratio mass spectrometry. Here we demonstrate that off-axis integrated cavity output (OA-ICOS) laser spectrometry, along with (2) H-enriched laboratory calibration standards and appropriate analysis templates, allows for low-cost, fast, and accurate determinations of water samples having δ(2) HVSMOW-SLAP values up to at least 57,000 ‰ (~9000 ppm) at a processing rate of 60 samples per day. As one practical application, extremely (2) H-enriched samples were measured by laser spectrometry and compared to the traditional (3) H Spike-Proxy method in order to determine tritium enrichment factors in the batch electrolysis of environmental waters. Highly (2) H-enriched samples were taken from different sets of electrolytically concentrated standards and low-level (enriched waters by laser spectrometry will facilitate the use of deuterium as a tracer in numerous environmental and other applications. For low-level tritium operations, this new analytical ability facilitated a 10-20 % increase in sample productivity through the elimination of spike standards and gravimetrics, and provides immediate feedback on electrolytic enrichment cell performance. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  4. Oak ridge national laboratory automated clean chemistry for bulk analysis of environmental swipe samples

    Energy Technology Data Exchange (ETDEWEB)

    Bostick, Debra A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hexel, Cole R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ticknor, Brian W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tevepaugh, Kayron N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Metzger, Shalina C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-11-01

    To shorten the lengthy and costly manual chemical purification procedures, sample preparation methods for mass spectrometry are being automated using commercial-off-the-shelf (COTS) equipment. This addresses a serious need in the nuclear safeguards community to debottleneck the separation of U and Pu in environmental samples—currently performed by overburdened chemists—with a method that allows unattended, overnight operation. In collaboration with Elemental Scientific Inc., the prepFAST-MC2 was designed based on current COTS equipment that was modified for U/Pu separations utilizing Eichrom™ TEVA and UTEVA resins. Initial verification of individual columns yielded small elution volumes with consistent elution profiles and good recovery. Combined column calibration demonstrated ample separation without crosscontamination of the eluent. Automated packing and unpacking of the built-in columns initially showed >15% deviation in resin loading by weight, which can lead to inconsistent separations. Optimization of the packing and unpacking methods led to a reduction in the variability of the packed resin to less than 5% daily. The reproducibility of the automated system was tested with samples containing 30 ng U and 15 pg Pu, which were separated in a series with alternating reagent blanks. These experiments showed very good washout of both the resin and the sample from the columns as evidenced by low blank values. Analysis of the major and minor isotope ratios for U and Pu provided values well within data quality limits for the International Atomic Energy Agency. Additionally, system process blanks spiked with 233U and 244Pu tracers were separated using the automated system after it was moved outside of a clean room and yielded levels equivalent to clean room blanks, confirming that the system can produce high quality results without the need for expensive clean room infrastructure. Comparison of the amount of personnel time necessary for successful manual vs

  5. Antimicrobial Resistance in Enterococcus spp. Isolated from Environmental Samples in an Area of Intensive Poultry Production

    Directory of Open Access Journals (Sweden)

    Patricia A. Chambers

    2013-03-01

    Full Text Available Enterococcus spp. from two poultry farms and proximate surface and ground water sites in an area of intensive poultry production were tested for resistance to 16 clinical antibiotics. Resistance patterns were compared to assess trends and possible correlations for specific antimicrobials and levels of resistance. Enterococci were detected at all 12 surface water sites and three of 28 ground water sites. Resistance to lincomycin, tetracycline, penicillin and ciprofloxacin in poultry litter isolates was high (80.3%, 65.3%, 61.1% and 49.6%, respectively. Resistance in the surface water to the same antibiotics was 87.1%, 24.1%, 7.6% and 12.9%, respectively. Overall, 86% of litter isolates, 58% of surface water isolates and 100% of ground water isolates were resistant to more than one antibiotic. Fifty-four different resistance patterns were recognised in isolates obtained from litter and environmental samples and several E. faecium and E. faecalis isolates from litter and environment samples shared the same resistance pattern. Multiple antibiotic resistant (MAR indices calculated to assess health risks due to the presence of resistant enterococci suggested an increased presence of antibiotics in surface water, likely from poultry sources as no other wastewater contributions in the area were documented.

  6. Determination of short-chained poly(ethylene glycols) and ethylene glycol in environmental samples.

    Science.gov (United States)

    Szymanski, A; Wyrwas, B; Szymanowska, M; Lukaszewski, Z

    2001-10-01

    A method for the determination of ethylene glycol (EG), di(ethylene glycol) (E2) and tri(ethylene glycol) (E3) in environmental samples (raw and treated sewage, river water) has been developed. These substances are important by-products in the biotransformation of non-ionic surfactants (NS). The method is based on sequential liquid-liquid extraction with ethyl acetate and chloroform (resulting in the separation of poly(ethylene glycols) (PEG) and EG from the water matrix), precipitation of long-chained PEG (PEGlch) with Dragendorff reagent, extraction of short-chained PEG (PEGsh) (EG, E2 and E3) from a filtrate with chloroform and the final determination using alternating current voltammetry. The precision of the method is 7.3%, the recovery 95% and a detection limit of 1.5 microg in the sample, i.e. 10 microg l(-1) was achieved. As evidenced by F and t tests, the developed method is equivalent to the indirect PEGsh determination by the difference approach where concentration of PEGsh is determined by the difference of the total PEG and PEGlch. The PEGsh fraction was found to be present in considerable concentrations in raw and treated sewage, river water, as well as being a major biotransformation by-product in the continuous flow activated sludge testing of fatty alcohol ethoxylates.

  7. Determining {sup 241}Pu in environmental samples. Case studies in alpine soils

    Energy Technology Data Exchange (ETDEWEB)

    Corcho Alvarado, J.A.; Chawla, F.; Froidevaux, P. [Lausanne Univ. Hospital Center (Switzerland). Inst. of Radiation Physics

    2011-07-01

    A procedure was developed for determining {sup 241}Pu activity in environmental samples. This beta emitter isotope of plutonium was measured by ultra low level liquid scintillation, after several separation and purification steps that involved the use of a highly selective extraction chromatographic resin (Eichrom-TEVA). Due to the lack of reference material for {sup 241}Pu, the method was nevertheless validated using four IAEA reference sediments with information values for {sup 241}Pu. Next, the method was used to determine the {sup 241}Pu activity in alpine soils of Switzerland and France. The {sup 241}Pu/{sup 239,240}Pu and {sup 238}Pu/{sup 239,240}Pu activity ratios confirmed that Pu contamination in the tested alpine soils originated mainly from global fallout from nuclear weapon tests conducted in the fifties and sixties. Estimation of the date of the contamination, using the {sup 241}Pu/{sup 241}Am age-dating method, further confirmed this origin. However, the {sup 241}Pu/{sup 241}Am dating method was limited to samples where Pu-Am fractionation was insignificant. If any, the contribution of the Chernobyl accident is negligible. (orig.)

  8. Using SPE-LC-ESI-MS/MS Analysis to Assess Disperse Dyes in Environmental Water Samples.

    Science.gov (United States)

    Zocolo, Guilherme Julião; Pilon dos Santos, Glauco; Vendemiatti, Josiane; Vacchi, Francine Inforçato; Umbuzeiro, Gisela de Aragão; Zanoni, Maria Valnice Boldrin

    2015-09-01

    We have optimized an SPE-LC-ESI-MS/MS method and used it to monitor disperse azo dyes in environmental aquatic samples. Calibration curves constructed for nine disperse dyes-Red 1, Violet 93, Blue 373, Orange 1, Orange 3, Orange 25, Yellow 3, Yellow 7 and Red 13-in aqueous solution presented good linearity between 2.0 and 100.0 ng mL(-1). The method provided limits of detection and quantification around 2.0 and 8.0 ng L(-1), respectively. For dyes at concentrations of 25.0 ng mL(-1), the intra- and interday analyses afforded relative standard deviation lower than 6 and 13%, respectively. The recovery values obtained for each target analyte in Milli-Q water, receiving waters and treated water samples spiked with the nine studied dyes at concentrations of 8.0, 25.0 and 50.0 ng L(-1) (n = 3) gave average recoveries greater than 70%, with RSD dyes Disperse Red 1, Disperse Blue 373 and Disperse Violet 93 at concentrations ranging from 84 to 3452 ng L(-1) in the treated effluent (TE), affluent and points collected upstream and downstream of the drinking water treatment plant of a textile dye industry in Brazil. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. [Environmental and biological determinants of neuropsychomotor development in a sample of children in Canoas/RS].

    Science.gov (United States)

    Pilz, Elsa Maria Luz; Schermann, Lígia Braun

    2007-01-01

    The object of this study is to determine the prevalence of potential delays in neuropsychomotor development and their possible association with, on one hand, environmental and biological factors, and maternal competence on the other, in a sample of children up to six years old living in Canoas, in Rio Grande do Sul state. A questionnaire was submitted to mothers including questions on social, economic and reproduction factors; child's conditions at birth; child's pathologies; family structure; child care and elements on maternal competence. The potential for neuropsychomotor development delay was assessed by the Denver II Test. Forty clusters were visited in Canoas, a city in Rio Grande do Sul state, in accordance with the cluster probabilistic sampling process. From 197 children assessed by this analytical cross-section study, there was a 27% (n=53) prevalence of potential delay in neuropsychomotor development. The multivariate analysis showed that factors associated with potential development delays were: low income (or = 9,3); mothers with less than 18-month intervals between pregnancies (or=3,9) ; and lack of support from child's father (or=7,0). These results support the importance of implementing income generating programs, health education, and family planning in order to prevent child development delays.

  10. Environmental DNA from seawater samples correlate with trawl catches of Subarctic, deepwater fishes

    DEFF Research Database (Denmark)

    Thomsen, Philip Francis; Møller, Peter Rask; Sigsgaard, Eva Egelyng

    2016-01-01

    Remote polar and deepwater fish faunas are under pressure from ongoing climate change and increasing fishing effort. However, these fish communities are difficult to monitor for logistic and financial reasons. Currently, monitoring of marine fishes largely relies on invasive techniques such as bo......Remote polar and deepwater fish faunas are under pressure from ongoing climate change and increasing fishing effort. However, these fish communities are difficult to monitor for logistic and financial reasons. Currently, monitoring of marine fishes largely relies on invasive techniques...... such as bottom trawling, and on official reporting of global catches, which can be unreliable. Thus, there is need for alternative and non-invasive techniques for qualitative and quantitative oceanic fish surveys. Here we report environmental DNA (eDNA) metabarcoding of seawater samples from continental slope...... depths in Southwest Greenland. We collected seawater samples at depths of 188-918 m and compared seawater eDNA to catch data from trawling. We used Illumina sequencing of PCR products to demonstrate that eDNA reads show equivalence to fishing catch data obtained from trawling. Twenty-six families were...

  11. Impact of sample size on principal component analysis ordination of an environmental data set: effects on eigenstructure

    Directory of Open Access Journals (Sweden)

    Shaukat S. Shahid

    2016-06-01

    Full Text Available In this study, we used bootstrap simulation of a real data set to investigate the impact of sample size (N = 20, 30, 40 and 50 on the eigenvalues and eigenvectors resulting from principal component analysis (PCA. For each sample size, 100 bootstrap samples were drawn from environmental data matrix pertaining to water quality variables (p = 22 of a small data set comprising of 55 samples (stations from where water samples were collected. Because in ecology and environmental sciences the data sets are invariably small owing to high cost of collection and analysis of samples, we restricted our study to relatively small sample sizes. We focused attention on comparison of first 6 eigenvectors and first 10 eigenvalues. Data sets were compared using agglomerative cluster analysis using Ward’s method that does not require any stringent distributional assumptions.

  12. Sample Canister Capture Mechanism for Mars Sample Return: Functional and environmental test of the elegant breadboard model

    Science.gov (United States)

    Carta, R.; Filippetto, D.; Lavagna, M.; Mailland, F.; Falkner, P.; Larranaga, J.

    2015-12-01

    The paper provides recent updates about the ESA study: Sample Canister Capture Mechanism Design and Breadboard developed under the Mars Robotic Exploration Preparation (MREP) program. The study is part of a set of feasibility studies aimed at identifying, analysing and developing technology concepts enabling the future international Mars Sample Return (MSR) mission. The MSR is a challenging mission with the purpose of sending a Lander to Mars, acquire samples from its surface/subsurface and bring them back to Earth for further, more in depth, analyses. In particular, the technology object of the Study is relevant to the Capture Mechanism that, mounted on the Orbiter, is in charge of capturing and securing the Sample Canister, or Orbiting Sample, accommodating the Martian soil samples, previously delivered in Martian orbit by the Mars Ascent Vehicle. An elegant breadboard of such a device was implemented and qualified under an ESA contract primed by OHB-CGS S.p.A. and supported by Politecnico di Milano, Department of Aerospace Science and Technology: in particular, functional tests were conducted at PoliMi-DAST and thermal and mechanical test campaigns occurred at Serms s.r.l. facility. The effectiveness of the breadboard design was demonstrated and the obtained results, together with the design challenges, issues and adopted solutions are critically presented in the paper. The breadboard was also tested on a parabolic flight to raise its Technology Readiness Level to 6; the microgravity experiment design, adopted solutions and results are presented as well in the paper.

  13. Arsenic speciation in environmental samples by hydride generation and electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Anawar, Hossain Md

    2012-01-15

    For the past few years many studies have been performed to determine arsenic (As) speciation in drinking water, food chain and other environmental samples due to its well-recognized carcinogenic and toxic effects relating to its chemical forms and oxidation states. This review provides an overview of analytical methods, preconcentration and separation techniques, developed up to now, using HGAAS and ETAAS for the determination of inorganic As and organoarsenic species in environmental samples. Specific advantages, disadvantages, selectivity, sensitivity, efficiency, rapidity, detection limit (DL), and some aspects of recent improvements and modifications for different analytical and separation techniques, that can define their application for a particular sample analysis, are highlighted. HG-AAS has high sensitivity, selectivity and low DL using suitable separation techniques; and it is a more suitable, affordable and much less expensive technique than other detectors. The concentrations of HCl and NaBH(4) have a critical effect on the HG response of As species. Use of l-cysteine as pre-reductant is advantageous over KI to obtain the same signal response for different As species under the same, optimum and mild acid concentration, and to reduce the interference of transition metals on the arsine generation. Use of different pretreatment, digestion, separation techniques and surfactants can determine As species with DL from ngL(-1) to μgL(-1). Out of all the chromatographic techniques coupled with HGAAS/ETAAS, ion-pair reversed-phase chromatography (IP-RP) is the most popular due to its higher separation efficiency, resolution selectivity, simplicity, and ability to separate up to seven As species for both non-ionic and ionic compounds in a signal run using the same column and short time. However, a combination of anion- and cation-exchange chromatography seems the most promising for complete resolution up to eight As species. The ETAAS method using different

  14. Detection of a diverse marine fish fauna using environmental DNA from seawater samples.

    Directory of Open Access Journals (Sweden)

    Philip Francis Thomsen

    Full Text Available Marine ecosystems worldwide are under threat with many fish species and populations suffering from human over-exploitation. This is greatly impacting global biodiversity, economy and human health. Intriguingly, marine fish are largely surveyed using selective and invasive methods, which are mostly limited to commercial species, and restricted to particular areas with favourable conditions. Furthermore, misidentification of species represents a major problem. Here, we investigate the potential of using metabarcoding of environmental DNA (eDNA obtained directly from seawater samples to account for marine fish biodiversity. This eDNA approach has recently been used successfully in freshwater environments, but never in marine settings. We isolate eDNA from ½-litre seawater samples collected in a temperate marine ecosystem in Denmark. Using next-generation DNA sequencing of PCR amplicons, we obtain eDNA from 15 different fish species, including both important consumption species, as well as species rarely or never recorded by conventional monitoring. We also detect eDNA from a rare vagrant species in the area; European pilchard (Sardina pilchardus. Additionally, we detect four bird species. Records in national databases confirmed the occurrence of all detected species. To investigate the efficiency of the eDNA approach, we compared its performance with 9 methods conventionally used in marine fish surveys. Promisingly, eDNA covered the fish diversity better than or equal to any of the applied conventional methods. Our study demonstrates that even small samples of seawater contain eDNA from a wide range of local fish species. Finally, in order to examine the potential dispersal of eDNA in oceans, we performed an experiment addressing eDNA degradation in seawater, which shows that even small (100-bp eDNA fragments degrades beyond detectability within days. Although further studies are needed to validate the eDNA approach in varying environmental

  15. Environmental DNA from Seawater Samples Correlate with Trawl Catches of Subarctic, Deepwater Fishes.

    Science.gov (United States)

    Thomsen, Philip Francis; Møller, Peter Rask; Sigsgaard, Eva Egelyng; Knudsen, Steen Wilhelm; Jørgensen, Ole Ankjær; Willerslev, Eske

    2016-01-01

    Remote polar and deepwater fish faunas are under pressure from ongoing climate change and increasing fishing effort. However, these fish communities are difficult to monitor for logistic and financial reasons. Currently, monitoring of marine fishes largely relies on invasive techniques such as bottom trawling, and on official reporting of global catches, which can be unreliable. Thus, there is need for alternative and non-invasive techniques for qualitative and quantitative oceanic fish surveys. Here we report environmental DNA (eDNA) metabarcoding of seawater samples from continental slope depths in Southwest Greenland. We collected seawater samples at depths of 188-918 m and compared seawater eDNA to catch data from trawling. We used Illumina sequencing of PCR products to demonstrate that eDNA reads show equivalence to fishing catch data obtained from trawling. Twenty-six families were found with both trawling and eDNA, while three families were found only with eDNA and two families were found only with trawling. Key commercial fish species for Greenland were the most abundant species in both eDNA reads and biomass catch, and interpolation of eDNA abundances between sampling sites showed good correspondence with catch sizes. Environmental DNA sequence reads from the fish assemblages correlated with biomass and abundance data obtained from trawling. Interestingly, the Greenland shark (Somniosus microcephalus) showed high abundance of eDNA reads despite only a single specimen being caught, demonstrating the relevance of the eDNA approach for large species that can probably avoid bottom trawls in most cases. Quantitative detection of marine fish using eDNA remains to be tested further to ascertain whether this technique is able to yield credible results for routine application in fisheries. Nevertheless, our study demonstrates that eDNA reads can be used as a qualitative and quantitative proxy for marine fish assemblages in deepwater oceanic habitats. This relates

  16. Environmental DNA from Seawater Samples Correlate with Trawl Catches of Subarctic, Deepwater Fishes.

    Directory of Open Access Journals (Sweden)

    Philip Francis Thomsen

    Full Text Available Remote polar and deepwater fish faunas are under pressure from ongoing climate change and increasing fishing effort. However, these fish communities are difficult to monitor for logistic and financial reasons. Currently, monitoring of marine fishes largely relies on invasive techniques such as bottom trawling, and on official reporting of global catches, which can be unreliable. Thus, there is need for alternative and non-invasive techniques for qualitative and quantitative oceanic fish surveys. Here we report environmental DNA (eDNA metabarcoding of seawater samples from continental slope depths in Southwest Greenland. We collected seawater samples at depths of 188-918 m and compared seawater eDNA to catch data from trawling. We used Illumina sequencing of PCR products to demonstrate that eDNA reads show equivalence to fishing catch data obtained from trawling. Twenty-six families were found with both trawling and eDNA, while three families were found only with eDNA and two families were found only with trawling. Key commercial fish species for Greenland were the most abundant species in both eDNA reads and biomass catch, and interpolation of eDNA abundances between sampling sites showed good correspondence with catch sizes. Environmental DNA sequence reads from the fish assemblages correlated with biomass and abundance data obtained from trawling. Interestingly, the Greenland shark (Somniosus microcephalus showed high abundance of eDNA reads despite only a single specimen being caught, demonstrating the relevance of the eDNA approach for large species that can probably avoid bottom trawls in most cases. Quantitative detection of marine fish using eDNA remains to be tested further to ascertain whether this technique is able to yield credible results for routine application in fisheries. Nevertheless, our study demonstrates that eDNA reads can be used as a qualitative and quantitative proxy for marine fish assemblages in deepwater oceanic

  17. Comparison of air samples, nasal swabs, ear-skin swabs and environmental dust samples for detection of Methicillin Resistant Staphylococcus aureus (MRSA) in pig herds

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Vigre, Håkan; Cavaco, Lina

    2014-01-01

    To identify a cost-effective and practical method for detection of methicillin-resistant Staphylococcus aureus (MRSA) in pig herds, the relative sensitivity of four sample types: nasal swabs, ear-skin (skin behind the ears) swabs, environmental dust swabs and air was compared. Moreover, dependency......-herd prevalence ⩾25%]. The results indicate that taking swabs of skin behind the ears (ten pools of five) was even more sensitive than taking nasal swabs (ten pools of five) at the herd level and detected significantly more positive samples. spa types t011, t034 and t4208 were observed. In conclusion, MRSA...... detection by air sampling is easy to perform, reduces costs and analytical time compared to existing methods, and is recommended for initial testing of herds. Ear-skin swab sampling may be more sensitive for MRSA detection than air sampling or nasal swab sampling....

  18. Maximizing the reliability of non-invasive endocrine sampling in the tiger (Panthera tigris): environmental decay and intra-sample variation in faecal glucocorticoid metabolites.

    Science.gov (United States)

    Parnell, Tempe; Narayan, Edward J; Nicolson, Vere; Martin-Vegue, Patrick; Mucci, Al; Hero, Jean-Marc

    2015-01-01

    Evaluation of physiological stress in the tiger (Panthera tigris) using faecal cortisol metabolite (FCM) enzyme immunoassays (EIAs) provides a powerful conservation physiology tool for the species. However, it is important to validate non-invasive endocrine sampling techniques in field conditions to ensure that the method provides a reliable parameter of physiological stress in the species. This is because endocrine measurements are highly species specific and FCM concentrations can be influenced by environmental factors. Here, we studied the impact of the decay rate of FCMs and intra-sample variation of FCMs using a previously validated EIA. To determine the decay rate of FCMs, we measured FCMs in freshly deposited tiger faeces (n = 8 tigers and 48 scats) that were randomly exposed to the natural environment (dry conditions with no rainfall) for up to 192 h. To determine intra-sample variation in FCMs, we used 10 scats from 10 tigers, divided each sample into four sections and each section into four sub-sections and measured FCMs in each section and sub-section. The results of this decay-rate experiment showed that FCMs in tiger faeces began to decay after 48 h exposure to the environmental conditions available. Thus, FCMs within freshly deposited tiger faeces are influenced by available environmental conditions. Changes in weather conditions (e.g. increased rainfall and humidity) could influence the stability of FCMs. The results of the intra-sample variation study showed that inter-variation among scats accounted for 52% of the variations in FCMs, while intra-sample variation between sections (32%) was greater than the sub-sample variation (16%). Intra-sample variation can be reduced by homogenizing the entire lyophilized faecal sample prior to the EIA. In conclusion, careful evaluation of decay rate and complete homogenization of faeces prior to EIA analysis will increase the reliability of FCMs as a non-invasive index of physiological stress in the

  19. Contribution of Organic Food to the Diet in a Large Sample of French Adults (the NutriNet-Santé Cohort Study

    Directory of Open Access Journals (Sweden)

    Julia Baudry

    2015-10-01

    Full Text Available In developed countries, the demand for organic products continues to substantially increase each year. However, little information is available regarding the level of consumption of organic food and its relative share of the whole diet. Our aim was to provide, using individual consumption data, a detailed description of organic food consumption among French adults. Conventional and organic intakes were assessed using an organic food frequency questionnaire administered to 28,245 French adults participating in the NutriNet-Santé study. P values of Student t-test or Chi-square for the difference between genders were reported. Less than 12% of the respondents reported never consuming organic food in the past year. Women consumed on average 20% organic food in their whole diet per day while men consumed an average of 18%. The proportion of vegetables consumed that came from organic sources was 31% among women and 28% among men. Overall, the estimate of the contribution of organic food from products of plant origin was higher than that from products of animal origin. Our study provides a framework for the exploration of organic consumption and its correlates and can serve as a basis for future studies investigating relationships between the level of organic food consumption and health outcomes.

  20. Contribution of Organic Food to the Diet in a Large Sample of French Adults (the NutriNet-Santé Cohort Study).

    Science.gov (United States)

    Baudry, Julia; Méjean, Caroline; Allès, Benjamin; Péneau, Sandrine; Touvier, Mathilde; Hercberg, Serge; Lairon, Denis; Galan, Pilar; Kesse-Guyot, Emmanuelle

    2015-10-21

    In developed countries, the demand for organic products continues to substantially increase each year. However, little information is available regarding the level of consumption of organic food and its relative share of the whole diet. Our aim was to provide, using individual consumption data, a detailed description of organic food consumption among French adults. Conventional and organic intakes were assessed using an organic food frequency questionnaire administered to 28,245 French adults participating in the NutriNet-Santé study. P values of Student t-test or Chi-square for the difference between genders were reported. Less than 12% of the respondents reported never consuming organic food in the past year. Women consumed on average 20% organic food in their whole diet per day while men consumed an average of 18%. The proportion of vegetables consumed that came from organic sources was 31% among women and 28% among men. Overall, the estimate of the contribution of organic food from products of plant origin was higher than that from products of animal origin. Our study provides a framework for the exploration of organic consumption and its correlates and can serve as a basis for future studies investigating relationships between the level of organic food consumption and health outcomes.

  1. Contribution of Organic Food to the Diet in a Large Sample of French Adults (the NutriNet-Santé Cohort Study)

    Science.gov (United States)

    Baudry, Julia; Méjean, Caroline; Allès, Benjamin; Péneau, Sandrine; Touvier, Mathilde; Hercberg, Serge; Lairon, Denis; Galan, Pilar; Kesse-Guyot, Emmanuelle

    2015-01-01

    In developed countries, the demand for organic products continues to substantially increase each year. However, little information is available regarding the level of consumption of organic food and its relative share of the whole diet. Our aim was to provide, using individual consumption data, a detailed description of organic food consumption among French adults. Conventional and organic intakes were assessed using an organic food frequency questionnaire administered to 28,245 French adults participating in the NutriNet-Santé study. P values of Student t-test or Chi-square for the difference between genders were reported. Less than 12% of the respondents reported never consuming organic food in the past year. Women consumed on average 20% organic food in their whole diet per day while men consumed an average of 18%. The proportion of vegetables consumed that came from organic sources was 31% among women and 28% among men. Overall, the estimate of the contribution of organic food from products of plant origin was higher than that from products of animal origin. Our study provides a framework for the exploration of organic consumption and its correlates and can serve as a basis for future studies investigating relationships between the level of organic food consumption and health outcomes. PMID:26506372

  2. Integration of Two SPAWAR PEOC4I NetCentric Technologies: Tactical Environmental Database Services (TEDServices) with the Extensible Tactical C4I Framework (XTCF)

    National Research Council Canada - National Science Library

    Bowers, Timothy H

    2007-01-01

    .... This was accomplished by delivering current weather data from Tactical Environmental Data Services (TEDServices), an API used to request meterological, oceanographic, and environmental information, through the Extensible Tactical C4I Framework...

  3. Sampling and Analysis Plan for Supplemental Environmental Project: Aquatic Life Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Berryhill, Jesse Tobias [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gaukler, Shannon Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-26

    As part of a settlement agreement for nuclear waste incidents in 2014, several supplemental environment projects (SEPs) were initiated at Los Alamos National Laboratory (LANL or the Laboratory) between the U.S. Department of Energy and the state of New Mexico. One SEP from this agreement consists of performing aquatic life surveys and will be used to assess the applicability of using generic ambient water-quality criteria (AWQC) for aquatic life. AWQC are generic criteria developed by the U.S. Environmental Protection Agency (EPA) to cover a broad range of aquatic species and are not unique to a specific region or state. AWQC are established by a composition of toxicity data, called species sensitivity distributions (SSDs), and are determined by LC50 (lethal concentration of 50% of the organisms studied) acute toxicity experiments for chemicals of interest. It is of interest to determine whether aquatic species inhabiting waters on the Pajarito Plateau are adequately protected using the current generic AWQC. The focus of this study will determine which aquatic species are present in ephemeral, intermittent, and perennial waters within LANL boundaries and from reference waters adjacent to LANL. If the species identified from these waters do not generally represent species used in the SSDs, then SSDs may need to be modified and AWQC may need to be updated. This sampling and analysis plan details the sampling methodology, surveillance locations, temporal scheduling, and analytical approaches that will be used to complete aquatic life surveys. A significant portion of this sampling and analysis plan was formalized by referring to Appendix E: SEP Aquatic Life Surveys DQO (Data Quality Objectives).

  4. Species-specific GC/ICP-IDMS for trimethyllead determinations in biological and environmental samples.

    Science.gov (United States)

    Poperechna, Nataliya; Heumann, Klaus G

    2005-01-15

    An accurate and sensitive species-specific isotope dilution GC/ICPMS method was developed for the determination of trimethyllead (Me3Pb+) in biological and environmental samples. A trimethyllead spike was synthesized from 206Pb-enriched metallic lead by reaction of lead halide with methyllithium and subsequent formation of trimethyllead iodide. The isotopic composition of the spike solution was determined by GC/ICPMS after derivatization with tetraethylborate, and its concentration was determined by reverse isotope dilution analysis. The species-specific GC/ICP-IDMS method was validated by reference material CRM 605 (urban dust) certified for Me3Pb+. The method was also applied to determine the Me3Pb+ content in six biological reference materials (DORM 2, CRM 278, CRM 422, CRM 463, CRM 477, MURST-ISS-A2) and one sediment reference material (CRM 580) for which no certified values of this species exist. The Me3Pb+ concentrations in the biological reference materials vary in the range of 0.3-17 ng g(-1) (as Pb) except for the Antarctic Krill (MURST-ISS-A2), where the concentration was less than the detection limit of 0.09 ng g(-1), which was also found for the sediment. Up to 20% of total lead was methylated in the biological reference materials, whereas much higher methylation fractions were found for mercury. The method was also applied to seafood samples purchased from a supermarket with Me3Pb+ concentrations in the limited range of 0.3-0.7 ng g(-1). On the contrary, the portion of methylated lead in these samples varied over more than 2 orders of magnitude from 0.02 to 7.5%.

  5. Discrimination between live and dead cells in bacterial communities from environmental water samples analyzed by 454 pyrosequencing

    NARCIS (Netherlands)

    Nocker, A.; Richter-Heitmann, T.; Montijn, R.; Schuren, F.; Kort, R.

    2010-01-01

    The preferential detection of cells with intact membranes by sample treatment with propidium monoazide (PMA) in combination with PCR amplification is gaining in popularity. This study evaluates the effect of PMA on 454 pyrosequencing profiles of environmental water samples from a canal in Amsterdam

  6. Sample preparation methods for the determination of plutonium and strontium in environmental samples by low level liquid scintillation counting and {alpha}-spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Solatie, D.; Carbol, P.; Hrnecek, E.; Betti, M. [European Commission, Joint Research Centre, Inst. for Transuranium Elements, Karlsruhe (Germany); Jaakkola, T. [Lab. of Radiochemistry, Univ. of Helsinki, Helsinki (Finland)

    2002-07-01

    Two different methods - leaching and microwave assisted total dissolution - have been exploited for the treatment of environmental samples for the determination of plutonium and strontium. Leaching applied to reference materials demonstrated the procedure to be applicable for the recovery of technogenic Pu and Sr from environmental samples. For the measurement of the alpha emitters of plutonium, co-precipitation with calcium oxalate and ferric hydroxide and separation with anion exchange has been used. For preparation of {alpha}-spectrometry sources, co-precipitation with NdF{sub 3} on a membrane filter or electro-deposition using the (NH{sub 4}){sub 2}C{sub 2}O{sub 4}/HCl method have been tested. The beta emitter {sup 241}Pu was measured by liquid scintillation counting. Pu isotope concentrations determined in the reference materials agreed well with the certified concentrations. {sup 90}Sr was measured in the leachate solutions from environmental samples collected close to a nuclear facility and from reference materials, after separation from the other leached elements, by liquid scintillation counting and Cherenkov counting. The {sup 90}Sr-concentrations determined in the reference materials agreed well with the certified concentrations. In the samples collected close a nuclear facility (soil, grass and sheep faeces), {sup 90}Sr was found at higher levels, which could also be correlated with the location of the sampling. (orig.)

  7. RadNet Air Quality (Fixed Station) Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — RadNet is a national network of monitoring stations that regularly collect air for analysis of radioactivity. The RadNet network, which has stations in each State,...

  8. Johne's disease: reliability of environmental sampling to characterize Mycobacterium avium subspecies paratuberculosis (MAP) infection in beef cow-calf herds.

    Science.gov (United States)

    Klawonn, W; Einax, E; Pützschel, R; Schmidt, M; Donat, K

    2016-08-01

    Environmental samples are considered to be a cost-effective method of identifying Mycobacterium avium subsp. paratuberculosis (MAP)-positive dairy herds, but evidence for beef cow-calf herds is weak. This study aims at evaluating this approach in a total of 20 German herds that were characterized by individual faecal samples (n = 2545) of all cows. For 14 MAP-positive herds having at least one MAP-positive animal, the within-herd prevalence was calculated from concurrent individual faecal culture-based testing. Six herds certified as 'MAP free' based on the negative results of previous years served as MAP-negative controls. On average, six environmental samples were taken at the end of winter from areas with high cow traffic and tested for MAP by faecal culture. According to the environmental samples, nine (64·3%) out of the 14 MAP-positive cow-calf herds were infected. The percentage of positive environmental samples and the apparent within-herd prevalence (Spearman's P = 0·73, P < 0·001) as well as the herd-level test results (positive and negative) and the herd's status based on individual testing (Fisher's exact test, P = 0·014) showed a positive association. Considering limitations in low-prevalence herds, MAP-positive beef cow-calf herds are detectable by environmental samples in temperate climate zones.

  9. Composition of aldrin, dieldrin, and photodieldrin enantiomers in technical and environmental samples.

    Science.gov (United States)

    Buser, Hans-Rudolf; Müller, Markus D; Buerge, Ignaz J; Poiger, Thomas

    2009-08-26

    Aldrin and dieldrin belong to the group of polycyclic chlorinated insecticides that are banned under the Stockholm Convention (POP Convention). Despite the fact that the use of these compounds ceased many years ago, aldrin and, in particular, dieldrin are still present in the environment from former applications, leading occasionally to contamination of agricultural produce and food, particularly Cucurbitaceae. These prochiral compounds have a complex stereochemistry. In the environment, aldrin is rapidly converted to its epoxide, dieldrin. Photolysis is one of the environmental transformation processes reported to be important for the compounds, leading to photoproducts such as photoaldrin and photodieldrin. In contrast to the parent compounds, photoaldrin and photodieldrin are chiral and exist as pairs of enantiomers. Although dieldrin and its metabolites have been extensively reviewed, the chirality of many of its metabolites has so far not been considered. In this study, the composition of technical aldrin and dieldrin from the 1950s and their photoproducts was investigated using both non-enantioselective and enantioselective gas chromatography with detection by several mass spectrometric techniques. Full enantiomer resolution of photodieldrin was achieved using a column with a silylated gamma-cyclodextrin as chiral selector. Photoaldrin, however, showed peak broadening, indicating some marginal resolution of the enantiomers. Whereas photodieldrin was formed as a racemate from both aldrin and dieldrin by natural sunlight, the analysis of environmental and biological samples (soil, biota) indicated its presence mostly with enantiomer compositions clearly differing from 1:1. The presence of photodieldrin in soil, treated more than 40 years ago with aldrin or dieldrin, documents that the photoreaction of dieldrin plays some role in the transformation of the compounds in the environment and that enantioselective biological processes are involved in its further

  10. Comparative analysis of metagenomes from three methanogenic hydrocarbon-degrading enrichment cultures with 41 environmental samples

    Science.gov (United States)

    Tan, Boonfei; Jane Fowler, S; Laban, Nidal Abu; Dong, Xiaoli; Sensen, Christoph W; Foght, Julia; Gieg, Lisa M

    2015-01-01

    Methanogenic hydrocarbon metabolism is a key process in subsurface oil reservoirs and hydrocarbon-contaminated environments and thus warrants greater understanding to improve current technologies for fossil fuel extraction and bioremediation. In this study, three hydrocarbon-degrading methanogenic cultures established from two geographically distinct environments and incubated with different hydrocarbon substrates (added as single hydrocarbons or as mixtures) were subjected to metagenomic and 16S rRNA gene pyrosequencing to test whether these differences affect the genetic potential and composition of the communities. Enrichment of different putative hydrocarbon-degrading bacteria in each culture appeared to be substrate dependent, though all cultures contained both acetate- and H2-utilizing methanogens. Despite differing hydrocarbon substrates and inoculum sources, all three cultures harbored genes for hydrocarbon activation by fumarate addition (bssA, assA, nmsA) and carboxylation (abcA, ancA), along with those for associated downstream pathways (bbs, bcr, bam), though the cultures incubated with hydrocarbon mixtures contained a broader diversity of fumarate addition genes. A comparative metagenomic analysis of the three cultures showed that they were functionally redundant despite their enrichment backgrounds, sharing multiple features associated with syntrophic hydrocarbon conversion to methane. In addition, a comparative analysis of the culture metagenomes with those of 41 environmental samples (containing varying proportions of methanogens) showed that the three cultures were functionally most similar to each other but distinct from other environments, including hydrocarbon-impacted environments (for example, oil sands tailings ponds and oil-affected marine sediments). This study provides a basis for understanding key functions and environmental selection in methanogenic hydrocarbon-associated communities. PMID:25734684

  11. Empirical testing of modified Salmonella MLST in aquatic environmental samples by in silico analysis.

    Science.gov (United States)

    Ho, Ying-Ning; Chou, Ming-Yuan; Tsai, Hsin-Chi; Huang, Tung-Yi; Fan, Cheng-Wei; Hsu, Bing-Mu

    2017-03-01

    Multilocus sequence typing (MLST) is an approach for prediction of Salmonella servoar and eBRUST groups (eBGs) based on seven typing scheme of housekeeping genes. Up to date, >220.000 allelic profiles and 65,973 Salmonella strains have been established in the MLST database. Several studies have modified MLST method with fewer targeted housekeeping genes for the purpose of economy and efficiency. Nevertheless, no study has conducted systematically to evaluate the correlation between the numbers of housekeeping genes targeted and the accuracy of prediction rate. In this study, we aimed to tackle this problem by extracting data from the MLST database as a whole using the software RStudio. Our results indicated that as the numbers of genes in MLST scheme increased, the accuracy of the eBGs prediction rate increased and reached 100% when the gene numbers are greater than or equal to 5. To examine the applicability of the approach, 395 environmental water samples were subjected to this study. A set of 52 Salmonella enterica isolates was initially used to develop MLST targeting seven housekeeping genes. A total of 29 sequence types, including 11 new sequence types were found among the 52 sequenced isolates that differentiated into 19 serotypes. Moreover, two novel sequence types did not belong to current classification. Our results show that the outcome in the three-gene sequence typing (aroC, hisD, and purE) was as accurate as in the seven-gene sequence typing for prediction of environmental Salmonella isolates. Our data suggested that this five-gene and reduced gene-number sequence-typing scheme can serve as an alternative modified MLST when effectiveness and financial management were the concerns. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Environmental DNA (eDNA sampling improves occurrence and detection estimates of invasive burmese pythons.

    Directory of Open Access Journals (Sweden)

    Margaret E Hunter

    Full Text Available Environmental DNA (eDNA methods are used to detect DNA that is shed into the aquatic environment by cryptic or low density species. Applied in eDNA studies, occupancy models can be used to estimate occurrence and detection probabilities and thereby account for imperfect detection. However, occupancy terminology has been applied inconsistently in eDNA studies, and many have calculated occurrence probabilities while not considering the effects of imperfect detection. Low detection of invasive giant constrictors using visual surveys and traps has hampered the estimation of occupancy and detection estimates needed for population management in southern Florida, USA. Giant constrictor snakes pose a threat to native species and the ecological restoration of the Florida Everglades. To assist with detection, we developed species-specific eDNA assays using quantitative PCR (qPCR for the Burmese python (Python molurus bivittatus, Northern African python (P. sebae, boa constrictor (Boa constrictor, and the green (Eunectes murinus and yellow anaconda (E. notaeus. Burmese pythons, Northern African pythons, and boa constrictors are established and reproducing, while the green and yellow anaconda have the potential to become established. We validated the python and boa constrictor assays using laboratory trials and tested all species in 21 field locations distributed in eight southern Florida regions. Burmese python eDNA was detected in 37 of 63 field sampling events; however, the other species were not detected. Although eDNA was heterogeneously distributed in the environment, occupancy models were able to provide the first estimates of detection probabilities, which were greater than 91%. Burmese python eDNA was detected along the leading northern edge of the known population boundary. The development of informative detection tools and eDNA occupancy models can improve conservation efforts in southern Florida and support more extensive studies of invasive

  13. Gold-FISH: A correlative approach to microscopic imaging of single microbial cells in environmental samples

    Science.gov (United States)

    Schmidt, Hannes; Seki, David; Woebken, Dagmar; Eickhorst, Thilo

    2017-04-01

    Fluorescence in situ hybridization (FISH) is routinely used for the phylogenetic identification, detection, and quantification of single microbial cells environmental microbiology. Oligonucleotide probes that match the 16S rRNA sequence of target organisms are generally applied and the resulting signals are visualized via fluorescence microscopy. Consequently, the detection of the microbial cells of interest is limited by the resolution and the sensitivity of light microscopy where objects smaller than 0.2 µm can hardly be represented. Visualizing microbial cells at magnifications beyond light microscopy, however, can provide information on the composition and potential complexity of microbial habitats - the actual sites of nutrient cycling in soil and sediments. We present a recently developed technique that combines (1) the phylogenetic identification and detection of individual microorganisms by epifluorescence microscopy, with (2) the in situ localization of gold-labelled target cells on an ultrastructural level by SEM. Based on 16S rRNA targeted in situ hybridization combined with catalyzed reporter deposition, a streptavidin conjugate labeled with a fluorescent dye and nanogold particles is introduced into whole microbial cells. A two-step visualization process including an autometallographic enhancement of nanogold particles then allows for either fluorescence or electron microscopy, or a correlative application thereof. We will present applications of the Gold-FISH protocol to samples of marine sediments, agricultural soils, and plant roots. The detection and enumeration of bacterial cells in soil and sediment samples was comparable to CARD-FISH applications via fluorescence microscopy. Examples of microbe-surface interaction analysis will be presented on the basis of bacteria colonizing the rhizoplane of rice roots. In principle, Gold-FISH can be performed on any material to give a snapshot of microbe-surface interactions and provides a promising tool for

  14. Environmental DNA (eDNA) sampling improves occurrence and detection estimates of invasive Burmese pythons

    Science.gov (United States)

    Hunter, Margaret E.; Oyler-McCance, Sara J.; Dorazio, Robert M.; Fike, Jennifer A.; Smith, Brian J.; Hunter, Charles T.; Reed, Robert N.; Hart, Kristen M.

    2015-01-01

    Environmental DNA (eDNA) methods are used to detect DNA that is shed into the aquatic environment by cryptic or low density species. Applied in eDNA studies, occupancy models can be used to estimate occurrence and detection probabilities and thereby account for imperfect detection. However, occupancy terminology has been applied inconsistently in eDNA studies, and many have calculated occurrence probabilities while not considering the effects of imperfect detection. Low detection of invasive giant constrictors using visual surveys and traps has hampered the estimation of occupancy and detection estimates needed for population management in southern Florida, USA. Giant constrictor snakes pose a threat to native species and the ecological restoration of the Florida Everglades. To assist with detection, we developed species-specific eDNA assays using quantitative PCR (qPCR) for the Burmese python (Python molurus bivittatus), Northern African python (P. sebae), boa constrictor (Boa constrictor), and the green (Eunectes murinus) and yellow anaconda (E. notaeus). Burmese pythons, Northern African pythons, and boa constrictors are established and reproducing, while the green and yellow anaconda have the potential to become established. We validated the python and boa constrictor assays using laboratory trials and tested all species in 21 field locations distributed in eight southern Florida regions. Burmese python eDNA was detected in 37 of 63 field sampling events; however, the other species were not detected. Although eDNA was heterogeneously distributed in the environment, occupancy models were able to provide the first estimates of detection probabilities, which were greater than 91%. Burmese python eDNA was detected along the leading northern edge of the known population boundary. The development of informative detection tools and eDNA occupancy models can improve conservation efforts in southern Florida and support more extensive studies of invasive constrictors

  15. Environmental DNA (eDNA) sampling improves occurrence and detection estimates of invasive burmese pythons.

    Science.gov (United States)

    Hunter, Margaret E; Oyler-McCance, Sara J; Dorazio, Robert M; Fike, Jennifer A; Smith, Brian J; Hunter, Charles T; Reed, Robert N; Hart, Kristen M

    2015-01-01

    Environmental DNA (eDNA) methods are used to detect DNA that is shed into the aquatic environment by cryptic or low density species. Applied in eDNA studies, occupancy models can be used to estimate occurrence and detection probabilities and thereby account for imperfect detection. However, occupancy terminology has been applied inconsistently in eDNA studies, and many have calculated occurrence probabilities while not considering the effects of imperfect detection. Low detection of invasive giant constrictors using visual surveys and traps has hampered the estimation of occupancy and detection estimates needed for population management in southern Florida, USA. Giant constrictor snakes pose a threat to native species and the ecological restoration of the Florida Everglades. To assist with detection, we developed species-specific eDNA assays using quantitative PCR (qPCR) for the Burmese python (Python molurus bivittatus), Northern African python (P. sebae), boa constrictor (Boa constrictor), and the green (Eunectes murinus) and yellow anaconda (E. notaeus). Burmese pythons, Northern African pythons, and boa constrictors are established and reproducing, while the green and yellow anaconda have the potential to become established. We validated the python and boa constrictor assays using laboratory trials and tested all species in 21 field locations distributed in eight southern Florida regions. Burmese python eDNA was detected in 37 of 63 field sampling events; however, the other species were not detected. Although eDNA was heterogeneously distributed in the environment, occupancy models were able to provide the first estimates of detection probabilities, which were greater than 91%. Burmese python eDNA was detected along the leading northern edge of the known population boundary. The development of informative detection tools and eDNA occupancy models can improve conservation efforts in southern Florida and support more extensive studies of invasive constrictors

  16. [Physicochemical Environmental Change during Bio-Preservation in Cellular and Biomolecular Suspension Samples and Its Effects on the Sample Quality].

    Science.gov (United States)

    Shirakashi, Ryo

    2015-01-01

    The quality of biospecimens is an important issue for clinical assays. These specimens contain various biomarkers, e.g., cells, proteins, nucleic acids, and phospholipids, most of which start to degrade just after sampling from patients. Because this degradation proceeds in a water-rich condition, under which water, as a solvent, dominates the degradation rate, the samples are often preserved at a low temperature in a frozen, lyophilized, or desiccated state to inhibit the motion of water molecules. However, frozen and/or desiccated water solutions surrounding the biomarkers markedly change the physicochemical environment, and can sometimes accelerate the degradation process. This physicochemical variation in water solutions includes dehydration by freezing or desiccation, osmotic stress by frozen-induced condensation, intra-/extracellular ice formation, and vitrification. This article provides an outline of such physicochemical variation in water solutions and its effects, especially on a fluid specimen, like a blood sample. The outline is composed of three parts after the introduction chapter: 1) general physicochemical changes in the water solution during freezing, frozen storage, and thawing, 2) damage of cells and proteins during freezing, frozen storage, and thawing, and 3) physicochemical changes of the water solution during desiccation and lyophilization and their effects on cells and proteins. As the mechanism of cellular damage is different from that of protein damage, they are discussed separately.

  17. Rapid Salmonella detection in experimentally inoculated equine faecal and veterinary hospital environmental samples using commercially available lateral flow immunoassays.

    Science.gov (United States)

    Burgess, B A; Noyes, N R; Bolte, D S; Hyatt, D R; van Metre, D C; Morley, P S

    2015-01-01

    Salmonella enterica is the most commonly reported cause of outbreaks of nosocomial infections in large animal veterinary teaching hospitals and the closure of equine hospitals. Rapid detection may facilitate effective control practices in equine populations. Shipping and laboratory testing typically require ≥48 h to obtain results. Lateral flow immunoassays developed for use in food-safety microbiology provide an alternative that has not been evaluated for use with faeces or environmental samples. We aimed to identify enrichment methods that would allow commercially available rapid Salmonella detection systems (lateral flow immunoassays) to be used in clinical practice with equine faecal and environmental samples, providing test results in 18-24 h. In vitro experiment. Equine faecal and environmental samples were inoculated with known quantities of S. enterica serotype Typhimurium and cultured using 2 different enrichment techniques for faeces and 4 enrichment techniques for environmental samples. Samples were tested blindly using 2 different lateral flow immunoassays and plated on agar media for confirmatory testing. In general, commercial lateral flow immunoassays resulted in fewer false-negative test results with enrichment of 1 g faecal samples in tetrathionate for 18 h, while all environmental sample enrichment techniques resulted in similar detection rates. The limit of detection from spiked samples, ∼4 colony-forming units/g, was similar for all methods evaluated. The lateral flow immunoassays evaluated could reliably detect S. enterica within 18 h, indicating that they may be useful for rapid point-of-care testing in equine practice applications. Additional evaluation is needed using samples from naturally infected cases and the environment to gain an accurate estimate of test sensitivity and specificity and to substantiate further the true value of these tests in clinical practice. © 2014 EVJ Ltd.

  18. Fingerprints of resistant Escherichia coli O157:H7 from vegetables and environmental samples.

    Science.gov (United States)

    Abakpa, Grace Onyukwo; Umoh, Veronica J; Kamaruzaman, Sijam; Ibekwe, Mark

    2018-01-01

    Some routes of transmission of Escherichia coli O157:H7 to fresh produce include contaminated irrigation water and manure polluted soils. The aim of the present study was to determine the genetic relationships of E. coli O157:H7 isolated from some produce growing region in Nigeria using enterobacterial repetitive intergenic consensus (ERIC) DNA fingerprinting analysis. A total of 440 samples comprising leafy greens, irrigation water, manure and soil were obtained from vegetable producing regions in Kano and Plateau States, Nigeria. Genes coding for the quinolone resistance-determinant (gyrA) and plasmid (pCT) coding for multidrug resistance (MDR) were determined using polymerase chain reaction (PCR) in 16 isolates that showed MDR. Cluster analysis of the ERIC-PCR profiles based on band sizes revealed six main clusters from the sixteen isolates analysed. The largest cluster (cluster 3) grouped isolates from vegetables and manure at a similarity coefficient of 0.72. The present study provides data that support the potential transmission of resistant strains of E. coli O157:H7 from vegetables and environmental sources to humans with potential public health implications, especially in developing countries. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. Genetic and environmental influences on psychological traits and eating attitudes in a sample of Spanish schoolchildren.

    Science.gov (United States)

    Rojo-Moreno, Luis; Iranzo-Tatay, Carmen; Gimeno-Clemente, Natalia; Barberá-Fons, Maria Antonia; Rojo-Bofill, Luis Miguel; Livianos-Aldana, Lorenzo

    The heritability of eating disorders has been estimated to range from 22% to over 62%.The aim of this study is to determine the relative influence of genetics and environment that contribute to the drive for thinness, body dissatisfaction, perfectionism, and ineffectiveness, by evaluating sex differences in a sample of adolescent twins from Valencia, Spain. Five hundred eighty-four pairs of adolescent twins between 13 and 18 years of age completed the study. To determine zygosity, teachers responded to a questionnaire on physical similarity. Psychological traits of eating disorders were assessed with four sub-scales of the Eating Disorder Inventory (EDI); drive for thinness, body dissatisfaction, perfectionism, and ineffectiveness. Twin models were used to assess genetic and environmental (common and unique) factors affecting these four psychological traits. All four traits showed significant genetic contributions among girls, with heritability estimates of 37.7% for ineffectiveness, 42.8% for perfectionism, 56.9% for drive for thinness, and 65.5% for body dissatisfaction. Among boys, body dissatisfaction showed no additive genetic contributions, indicating significant shared and individual specific environment effects. The three other traits in boys showed significant additive genetic contributions, but were lower than in girls. With the exception of body dissatisfaction in boys, psychological traits of eating disorders show heritability patterns that differ according to sex. Copyright © 2014 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Production and release of selenocyanate by different green freshwater algae in environmental and laboratory samples.

    Science.gov (United States)

    LeBlanc, Kelly L; Smith, Matthew S; Wallschläger, Dirk

    2012-06-05

    In a previous study, selenocyanate was tentatively identified as a biotransformation product when green algae were exposed to environmentally relevant concentrations of selenate. In this follow-up study, we confirm conclusively the presence of selenocyanate in Chlorella vulgaris culture medium by electrospray mass spectrometry, based on selenium's known isotopic pattern. We also demonstrate that the observed phenomenon extends to other green algae (Chlorella kesslerii and Scenedesmus obliquus) and at least one species of blue-green algae (Synechococcus leopoliensis). Further laboratory experiments show that selenocyanate production by algae is enhanced by addition of nitrate, which appears to serve as a source of cyanide produced in the algae. Ultimately, this biotransformation process was confirmed in field experiments where trace amounts of selenocyanate (0.215 ± 0.010 ppb) were observed in a eutrophic, selenium-impacted river with massive algal blooms, which consisted of filamentous green algae (Cladophora genus) and blue-green algae (Anabaena genus). Selenocyanate abundance was low despite elevated selenium concentrations, apparently due to suppression of selenate uptake by sulfate, and insufficient nitrogen concentrations. Finally, trace levels of several other unidentified selenium-containing compounds were observed in these river water samples; preliminary suggestions for their identities include thioselenate and small organic Se species.

  1. National intercomparison programme for radionuclide analysis in environmental samples: Aramar radioecological laboratory performance

    Energy Technology Data Exchange (ETDEWEB)

    Arine, Bruno Burini Robles, E-mail: bruno.arine@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP/ARAMAR), Ipero, SP (Brazil). Lab. Radioecologico; Moraes, Marco Antonio P.V., E-mail: marco.proenca@ctmsp.mar.mil.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The radioecological laboratory is concerned with the measurements of background radiation (mainly uranium and thorium natural series) and present effluents in the Aramar Experimental Centre, as well as in its surroundings. The laboratory is directly subordinated to the Navy Technological Centre in Sao Paulo (CTMSP - Sao Paulo - Brazil), a military research organization whose goal is to develop nuclear and energy systems for the Brazilian naval ship propulsion. The measurements were performed in addition to the Environmental Monitoring Programme carried out in the same region. For this endeavour, the laboratory has attended to the National Intercomparison Programme conducted by the Institute for Radioprotection and Dosimetry (IRD) by analyzing several kinds of solid and liquid samples containing specific radionuclides through gamma spectrometry, liquid scintillation, alpha-beta total counting and fluorimetry techniques, since December 1995. In the last 15 years, our results were compared to another 19 laboratories and rated as 'very good' and 'acceptable' in at least 90% of the results. (author)

  2. RadNet Air Quality (Deployable) Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — RadNet Deployable Monitoring is designed to collect radiological and meteorological information and data asset needed to establish the impact of radiation levels on...

  3. Strategies for quantifying C60 fullerenes in environmental and biological samples and implications for studies in environmental health and ecotoxicology

    OpenAIRE

    Pycke, Benny F. G.; Benn, Troy M.; Herckes, Pierre; Westerhoff, Paul; Halden, Rolf U.

    2011-01-01

    Fullerenes are sphere-like molecules with unique physico-chemical properties, which render them of particular interest in biomedical research, consumer products and industrial applications. Human and environmental exposure to fullerenes is not a new phenomenon, due to a long history of hydrocarbon-combustion sources, and will only increase in the future, as incorporation of fullerenes into consumer products becomes more widespread for use as anti-aging, anti-bacterial or anti-apoptotic agents.

  4. Automated Gel Size Selection to Improve the Quality of Next-generation Sequencing Libraries Prepared from Environmental Water Samples.

    Science.gov (United States)

    Uyaguari-Diaz, Miguel I; Slobodan, Jared R; Nesbitt, Matthew J; Croxen, Matthew A; Isaac-Renton, Judith; Prystajecky, Natalie A; Tang, Patrick

    2015-04-17

    Next-generation sequencing of environmental samples can be challenging because of the variable DNA quantity and quality in these samples. High quality DNA libraries are needed for optimal results from next-generation sequencing. Environmental samples such as water may have low quality and quantities of DNA as well as contaminants that co-precipitate with DNA. The mechanical and enzymatic processes involved in extraction and library preparation may further damage the DNA. Gel size selection enables purification and recovery of DNA fragments of a defined size for sequencing applications. Nevertheless, this task is one of the most time-consuming steps in the DNA library preparation workflow. The protocol described here enables complete automation of agarose gel loading, electrophoretic analysis, and recovery of targeted DNA fragments. In this study, we describe a high-throughput approach to prepare high quality DNA libraries from freshwater samples that can be applied also to other environmental samples. We used an indirect approach to concentrate bacterial cells from environmental freshwater samples; DNA was extracted using a commercially available DNA extraction kit, and DNA libraries were prepared using a commercial transposon-based protocol. DNA fragments of 500 to 800 bp were gel size selected using Ranger Technology, an automated electrophoresis workstation. Sequencing of the size-selected DNA libraries demonstrated significant improvements to read length and quality of the sequencing reads.

  5. Aquatic passive sampling of perfluorinated chemicals with polar organic chemical integrative sampler and environmental factors affecting sampling rate.

    Science.gov (United States)

    Li, Ying; Yang, Cunman; Bao, Yijun; Ma, Xueru; Lu, Guanghua; Li, Yi

    2016-08-01

    A modified polar organic chemical integrative sampler (POCIS) could provide a convenient way of monitoring perfluorinated chemicals (PFCs) in water. In the present study, the modified POCIS was calibrated to monitor PFCs. The effects of water temperature, pH, and dissolved organic matter (DOM) on the sampling rate (R s) of PFCs were evaluated with a static renewal system. During laboratory validation over a 14-day period, the uptake kinetics of PFCs was linear with the POCIS. DOM and water temperature slightly influenced POCIS uptake rates, which is in consistent with the theory for uptake into POCIS. Therefore, within a narrow span of DOM and water temperatures, it was unnecessary to adjust the R s value for POCIS. Laboratory experiments were conducted with water over pH ranges of 3, 7, and 9. The R s values declined significantly with pH increase for PFCs. Although pH affected the uptake of PFCs, the effect was less than twofold. Application of the R s value to analyze PFCs with POCIS deployed in the field provided similar concentrations obtained from grab samples.

  6. Graphene-enhanced plasmonic nanohole arrays for environmental sensing in aqueous samples

    Directory of Open Access Journals (Sweden)

    Christa Genslein

    2016-11-01

    Full Text Available The label-free nature of surface plasmon resonance techniques (SPR enables a fast, specific, and sensitive analysis of molecular interactions. However, detection of highly diluted concentrations and small molecules is still challenging. It is shown here that in contrast to continuous gold films, gold nanohole arrays can significantly improve the performance of SPR devices in angle-dependent measurement mode, as a signal amplification arises from localized surface plasmons at the nanostructures. This leads consequently to an increased sensing capability of molecules bound to the nanohole array surface. Furthermore, a reduced graphene oxide (rGO sensor surface was layered over the nanohole array. Reduced graphene oxide is a 2D nanomaterial consisting of sp2-hybridized carbon atoms and is an attractive receptor surface for SPR as it omits any bulk phase and therefore allows fast response times. In fact, it was found that nanohole arrays demonstrated a higher shift in the resonance angle of 250–380% compared to a continuous gold film. At the same time the nanohole array structure as characterized by its diameter-to-periodicity ratio had minimal influence on the binding capacity of the sensor surface. As a simple and environmentally highly relevant model, binding of the plasticizer diethyl phthalate (DEP via π-stacking was monitored on the rGO gold nanohole array realizing a limit of detection of as low as 20 nM. The concentration-dependent signal change was studied with the best performing rGO-modified nanohole arrays. Compared to continuous gold films a diameter-to-periodicity ratio (D/P of 0.43 lead to a 12-fold signal enhancement. Finally, the effect of environmental waters on the sensor was evaluated using samples from sea, lake and river waters spiked with analytically relevant amounts of DEP during which significant changes in the SPR signal are observed. It is expected that this concept can be successfully transferred to enhance the

  7. NA-NET numerical analysis net

    Energy Technology Data Exchange (ETDEWEB)

    Dongarra, J. [Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science]|[Oak Ridge National Lab., TN (United States); Rosener, B. [Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science

    1991-12-01

    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host ``na-net.ornl.gov`` at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message ``send index`` to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user`s perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  8. NA-NET numerical analysis net

    Energy Technology Data Exchange (ETDEWEB)

    Dongarra, J. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science Oak Ridge National Lab., TN (United States)); Rosener, B. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science)

    1991-12-01

    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host na-net.ornl.gov'' at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message send index'' to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user's perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  9. A probe-based quantitative PCR assay for detecting Tetracapsuloides bryosalmonae in fish tissue and environmental DNA water samples

    Science.gov (United States)

    Hutchins, Patrick; Sepulveda, Adam; Martin, Renee; Hopper, Lacey

    2017-01-01

    A probe-based quantitative real-time PCR assay was developed to detect Tetracapsuloides bryosalmonae, which causes proliferative kidney disease in salmonid fish, in kidney tissue and environmental DNA (eDNA) water samples. The limits of detection and quantification were 7 and 100 DNA copies for calibration standards and T. bryosalmonae was reliably detected down to 100 copies in tissue and eDNA samples. The assay presented here is a highly sensitive and quantitative tool for detecting T. bryosalmonae with potential applications for tissue diagnostics and environmental detection.

  10. Monitoring of noble, signal and narrow-clawed crayfish using environmental DNA from freshwater samples.

    Directory of Open Access Journals (Sweden)

    Sune Agersnap

    Full Text Available For several hundred years freshwater crayfish (Crustacea-Decapoda-Astacidea have played an important ecological, cultural and culinary role in Scandinavia. However, many native populations of noble crayfish Astacus astacus have faced major declines during the last century, largely resulting from human assisted expansion of non-indigenous signal crayfish Pacifastacus leniusculus that carry and transmit the crayfish plague pathogen. In Denmark, also the non-indigenous narrow-clawed crayfish Astacus leptodactylus has expanded due to anthropogenic activities. Knowledge about crayfish distribution and early detection of non-indigenous and invasive species are crucial elements in successful conservation of indigenous crayfish. The use of environmental DNA (eDNA extracted from water samples is a promising new tool for early and non-invasive detection of species in aquatic environments. In the present study, we have developed and tested quantitative PCR (qPCR assays for species-specific detection and quantification of the three above mentioned crayfish species on the basis of mitochondrial cytochrome oxidase 1 (mtDNA-CO1, including separate assays for two clades of A. leptodactylus. The limit of detection (LOD was experimentally established as 5 copies/PCR with two different approaches, and the limit of quantification (LOQ were determined to 5 and 10 copies/PCR, respectively, depending on chosen approach. The assays detected crayfish in natural freshwater ecosystems with known populations of all three species, and show promising potentials for future monitoring of A. astacus, P. leniusculus and A. leptodactylus. However, the assays need further validation with data 1 comparing traditional and eDNA based estimates of abundance, and 2 representing a broader geographical range for the involved crayfish species.

  11. Mobilization Protocols for Hybrid Sensors for Environmental AOP Sampling (HySEAS) Observations

    Science.gov (United States)

    Hooker, Stanford B.

    2014-01-01

    The protocols presented here enable the proper mobilization of the latest-generation instruments for measuring the apparent optical properties (AOPs) of aquatic ecosystems. The protocols are designed for the Hybrid Sensors for Environmental AOP Sampling (HySEAS) class of instruments, but are applicable to the community of practice for AOP measurements. The protocols are organized into eleven sections beyond an introductory overview: a) cables and connectors, b) HySEAS instruments, c) platform preparation, d) instrument installation, e) cable installation, f) test deployment, g) test recovery, h) maintenance, i) shipping, j) storage, and k) smallboat operations. Each section concentrates on documenting how to prevent the most likely faults, remedy them should they occur, and accomplishing both with the proper application of a modest set of useful tools. Within the twelve sections, there are Socratic exercises to stimulate thought, and the answers to these exercises appear in Appendix A. Frequently asked questions (FAQs) are summarized in a separate section after the answers to the exercises in Appendix B. For practitioners unfamiliar with the nautical terms used throughout this document plus others likely encountered at sea, an abbreviated dictionary of nautical terms appears in Appendix C. An abbreviated dictionary of radiotelephone terms is presented in Appendix D. To ensure familiarity with many of the tools that are presented, Appendix E provides a description of the tools alongside a thumbnail picture. Abbreviated deployment checklists and cable diagrams are provided in Appendix F. The document concludes with an acknowledgments section, a glossary of acronyms, a definition of symbols, and a list of references.

  12. Preparative chromatography for specific δ13C isotopic analysis of individual carbohydrates in environmental samples

    Science.gov (United States)

    Nouara, Amel; Panagiotopoulos, Christos; Balesdent, Jérôme; Sempéré, Richard

    2017-04-01

    Carbohydrates are among the most abundant organic molecules on the Earth and are present in all geochemical systems. Despite their high abundance in the environment, very few studies assessed their origin using molecular carbohydrate isotopic analyses. In contrast with bulk stable isotope analysis (BSIA), which gives the isotopic signature of the entire sample without any specification about its chemical composition, compound specific 13C isotopic analysis of individual sugars (CSIA) offers valuable information about the origin of single molecules. Previous investigations used gas or liquid chromatography coupled with isotope ratio mass spectroscopy (GC-IRMS; HPLC-IRMS) for CSIA of sugars however the former requires δ13C corrections due to the carbon added to the sugar (derivatization) while the later does not provide always adequate separations among monosaccharides. Here we used cation preparative chromatography (Ca2+, Pb2+ and Na+) with refractive index detection in order to produce pure monosaccharide targets for subsequent EA-IRMS analyses. Milli-Q water was used as eluant at a flow rate 0.6 ml min-1. In general, three successive purifications (Ca2+, Pb2+, Ca2+) were sufficient to produce pure compounds. Pure monosaccharides were compared with authentic monosaccharide standards using 1H NMR and/or mass spectroscopy. The detection limit of our technique was about 1µM/sugar with a precision of 10% (n=6). Blanks run with Milli-Q water after three successive purifications resulted in carbon content of 0.13 to 2.77 µgC per collected sugar. These values are much lower than the minimum required amount (5 µgC) of the EA-IRSMS system with a precision of ± 0.35 ‰. Application of our method to environmental samples resulted in δ13C values of glucose, fructose, and levoglucosan in the range of -24 to -26 ‰ (PM10 atmospheric particles), and -15‰ to -22 ‰ for arabinose, glucose, and xylose (marine high molecular dissolved organic matter). These results fall in

  13. Separation and enrichment of gold(III) from environmental samples prior to its flame atomic absorption spectrometric determination.

    Science.gov (United States)

    Senturk, Hasan Basri; Gundogdu, Ali; Bulut, Volkan Numan; Duran, Celal; Soylak, Mustafa; Elci, Latif; Tufekci, Mehmet

    2007-10-22

    A simple and accurate method was developed for separation and enrichment of trace levels of gold in environmental samples. The method is based on the adsorption of Au(III)-diethyldithiocarbamate complex on Amberlite XAD-2000 resin prior to the analysis of gold by flame atomic absorption spectrometry after elution with 1 molL(-1) HNO3 in acetone. Some parameters including nitric acid concentration, eluent type, matrix ions, sample volume, sample flow rate and adsorption capacity were investigated on the recovery of gold(III). The recovery values for gold(III) and detection limit of gold were greater than 95% and 16.6 microgL(-1), respectively. The preconcentration factor was 200. The relative standard deviation of the method was gold in some environmental samples.

  14. A semi-empirical approach to determine gamma activities (Bqkg{sup -1}) in environmental cylindrical samples

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, Daniel Francisco [Universidad Simon Bolivar (USB), Apartado 89000, Caracas (Venezuela)], E-mail: palacios@usb.ve; Alfonso, Juan A. [Instituto Venezolano de Investigaciones Cientificas (IVIC), Apartado 21827, Caracas (Venezuela); Barros, Haydn [Universidad Simon Bolivar (USB), Apartado 89000, Caracas (Venezuela); LaBrecque, John J.; Perez, Karla [Instituto Venezolano de Investigaciones Cientificas (IVIC), Apartado 21827, Caracas (Venezuela); Lossada, Marian R. [Direccion de Investigacion y Postgrado, Universidad Maritima del Caribe (UMC), Caracas (Venezuela)

    2008-01-15

    A semi-empirical method to determine radionuclide concentrations in large environmental samples without the use of reference material and avoiding the typical complexity of Monte-Carlo codes is proposed. The calculation of full-energy peak efficiencies was carried out from a relative efficiency curve (obtained from the gamma spectra data), and the geometric (simulated by Monte-Carlo), absorption, sample and intrinsic efficiencies for energies between 130 and 3000 keV. The absorption and sample efficiencies were determined from the mass absorption coefficients, whereas the intrinsic efficiency was approximated by an empirical function. The deviations between calculated and experimental efficiencies for a reference material in most cases are less than 10%. Radionuclide activities in marine sediment samples calculated by the proposed method and by the experimental comparative method were not significantly different. This new method can be used for routine environmental monitoring when uncertainties up to 10% are acceptable.

  15. High herd-level prevalence of Mycobacterium avium subspecies paratuberculosis in Western Canadian dairy farms, based on environmental sampling.

    Science.gov (United States)

    Wolf, R; Barkema, H W; De Buck, J; Slomp, M; Flaig, J; Haupstein, D; Pickel, C; Orsel, K

    2014-10-01

    Mycobacterium avium subspecies paratuberculosis (MAP) causes chronic progressive enteritis in ruminants. The pathogen is present in most countries with modern dairy production, causing substantial economic losses for the industry. The objectives of this study were to estimate dairy herd prevalence of MAP in the Western Canadian provinces of Alberta and Saskatchewan, and to determine whether herd size and housing system (tie-stall versus freestall or loose housing) affected the risk of a herd testing positive for MAP. Six environmental samples were collected on 360 Alberta farms (60% of registered producers) and on 166 Saskatchewan dairy farms (99%). In total, 47% of the sampled farms in Alberta and 53% of the sampled farms in Saskatchewan had at least one environmental sample that was MAP culture positive and were, therefore, defined as infected. Sensitivity of environmental sampling was estimated using 3 subsequent annual tests performed on 82 farms. Because laboratory protocols were continuously improved throughout the project, the sensitivity increased over time. Therefore, a mean of the sensitivity estimates weighted on sampling year was constructed; this resulted in sensitivities of 68 and 69% for Alberta and Saskatchewan, respectively. Implementing those estimates in an approximate Bayesian computation model resulted in a true herd prevalence of 68% (95% probability interval: 60-80%) for Alberta and 76% (95% probability interval: 70-85%) for Saskatchewan. Herds with >200 cows had 3.54 times higher odds of being environmental sample positive and had more positive samples than herds with <50 cows (neither province nor housing system affected those results). In conclusion, the majority of Alberta and Saskatchewan dairy farms were infected with MAP and larger herds were more often MAP positive than smaller herds. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. Net Ecosystem Carbon Flux

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Net Ecosystem Carbon Flux is defined as the year-over-year change in Total Ecosystem Carbon Stock, or the net rate of carbon exchange between an ecosystem and the...

  17. Net ground speed of downstream migrating radio-tagged Atlantic salmon ( Salmo salar L.) and brown trout ( Salmo trutta L.) smolts in relation to environmental factors

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Nielsen, C.; Koed, Anders

    2002-01-01

    tagged and released in the Danish River Lilleaa. The downstream migration of the different groups of fish was monitored by manual tracking and by three automatic listening stations. The downstream migration of radio tagged smolts of both species occurred concurrently with their untagged counterparts......The downstream migration of Atlantic salmon (Salmo salar L.) and sea trout smolt (S. trutta L.) was investigated using radio telemetry in the spring of 1999 and 2000. Forty wild sea trout smolts, 20 F1 sea trout smolts, 20 hatchery salmon smolts and 20 salmon smolts from river stockings were radio....... The diel migration pattern of the radio tagged smolts was predominantly nocturnal in both species. Wild sea trout smolt migrated significantly faster than both the F1 trout and the introduced salmon. There was no correlation between net ground speed, gill Na+, K+-ATPase activity or fish length in any...

  18. Modern sample preparation techniques for gas chromatography-mass spectrometry analysis of environmental markers of chemical warfare agents use

    NARCIS (Netherlands)

    Terzic, O.; de Voogt, P.; Banoub, J.

    2014-01-01

    The chapter introduces problematics of on-site chemical analysis in the investigations of past chemical warfare agents (CWA) events. An overview of primary environmental degradation pathways of CWA leading to formation of chemical markers of their use is given. Conventional and modern sample

  19. Rapid analysis of organic microcontaminants in environmental water samples by trace enrichment and liquid chromatography on a single short column.

    NARCIS (Netherlands)

    Hogenboom, A.C.; Malmqvist, U.K.; Nolkrantz, K.; Vreuls, J.J.; Brinkman, U.A.T.

    1997-01-01

    On-column trace enrichment and liquid chromatography using a single short (20 mm length) high-pressure packed column was optimized for the rapid simultaneous identification and quantification of a wide range of organic microcontaminants in environmental water samples. The quality of different C,,

  20. Factors associated with mosquito net use by individuals in households owning nets in Ethiopia

    Directory of Open Access Journals (Sweden)

    Graves Patricia M

    2011-12-01

    Full Text Available Abstract Background Ownership of insecticidal mosquito nets has dramatically increased in Ethiopia since 2006, but the proportion of persons with access to such nets who use them has declined. It is important to understand individual level net use factors in the context of the home to modify programmes so as to maximize net use. Methods Generalized linear latent and mixed models (GLLAMM were used to investigate net use using individual level data from people living in net-owning households from two surveys in Ethiopia: baseline 2006 included 12,678 individuals from 2,468 households and a sub-sample of the Malaria Indicator Survey (MIS in 2007 included 14,663 individuals from 3,353 households. Individual factors (age, sex, pregnancy; net factors (condition, age, net density; household factors (number of rooms [2006] or sleeping spaces [2007], IRS, women's knowledge and school attendance [2007 only], wealth, altitude; and cluster level factors (rural or urban were investigated in univariate and multi-variable models for each survey. Results In 2006, increased net use was associated with: age 25-49 years (adjusted (a OR = 1.4, 95% confidence interval (CI 1.2-1.7 compared to children U5; female gender (aOR = 1.4; 95% CI 1.2-1.5; fewer nets with holes (Ptrend = 0.002; and increasing net density (Ptrend [all nets in HH good] = 1.6; 95% CI 1.2-2.1; increasing net density (Ptrend [per additional space] = 0.6, 95% CI 0.5-0.7; more old nets (aOR [all nets in HH older than 12 months] = 0.5; 95% CI 0.3-0.7; and increasing household altitude (Ptrend Conclusion In both surveys, net use was more likely by women, if nets had fewer holes and were at higher net per person density within households. School-age children and young adults were much less likely to use a net. Increasing availability of nets within households (i.e. increasing net density, and improving net condition while focusing on education and promotion of net use, especially in school-age children

  1. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - BAGHOUSE FILTRATION PRODUCTS - INSPEC FIBRES 5512BRF FILTER SAMPLE

    Science.gov (United States)

    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of th...

  2. PFAS methods and guidance for sampling and analyzing water and other environmental media (Technical Brief)

    Science.gov (United States)

    EPA's methods for analyzing PFAS in environmental media are in various stages of development. This fact sheet summarizes EPA's analytical methods development for groundwater, surface water, wastewater, and solids, including soils, sediments, and biosolids

  3. PFAS Sampling Studies and Methods Development for Water and Other Environmental Media (Technical Brief)

    Science.gov (United States)

    EPA's methods for analyzing PFAS in environmental media are in various stages of development. This fact sheet summarizes EPA's analytical methods development for groundwater, surface water, wastewater, and solids, including soils, sediments, and biosolids

  4. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - BAGHOUSE FILTRATION PRODUCTS - STANDARD FILTER CORPORATION PE16ZU FILTER SAMPLE

    Science.gov (United States)

    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of th...

  5. Implementing NetScaler VPX

    CERN Document Server

    Sandbu, Marius

    2014-01-01

    An easy-to-follow guide with detailed step-by step-instructions on how to implement the different key components in NetScaler, with real-world examples and sample scenarios.If you are a Citrix or network administrator who needs to implement NetScaler in your virtual environment to gain an insight on its functionality, this book is ideal for you. A basic understanding of networking and familiarity with some of the different Citrix products such as XenApp or XenDesktop is a prerequisite.

  6. Professional Enterprise NET

    CERN Document Server

    Arking, Jon

    2010-01-01

    Comprehensive coverage to help experienced .NET developers create flexible, extensible enterprise application code If you're an experienced Microsoft .NET developer, you'll find in this book a road map to the latest enterprise development methodologies. It covers the tools you will use in addition to Visual Studio, including Spring.NET and nUnit, and applies to development with ASP.NET, C#, VB, Office (VBA), and database. You will find comprehensive coverage of the tools and practices that professional .NET developers need to master in order to build enterprise more flexible, testable, and ext

  7. A Discussion of Procedures and Equipment for the Comprehensive Test Ban Treaty On-Site Inspection Environmental Sampling and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wogman, Ned A.; Milbrath, Brian D.; Payne, Rosara F.; Seifert, Carolyn E.; Friese, Judah I.; Miley, Harry S.; Bowyer, Ted W.; Hanlen, Richard C.; Onishi, Yasuo; Hayes, James C.; Wigmosta, Mark S.

    2011-02-01

    This paper is intended to serve as a scientific basis to start discussions of the available environmental sampling techniques and equipment that have been used in the past that could be considered for use within the context of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) on-site inspections (OSI). This work contains information on the techniques, equipment, costs, and some operational procedures associated with environmental sampling that have actually been used in the past by the United States for the detection of nuclear explosions. This paper also includes a discussion of issues, recommendations, and questions needing further study within the context of the sampling and analysis of aquatic materials, atmospheric gases, atmospheric particulates, vegetation, sediments and soils, fauna, and drill-back materials.

  8. The influence of sampling intensity on vegetation classification and the implications for environmental management

    NARCIS (Netherlands)

    Cooper, A.; Mccan, T.; Bunce, R.G.H.

    2006-01-01

    As part of a programme of landscape-scale habitat surveillance in the United Kingdom (UK), the effect of grassland sampling intensity on the outcome of numerical classification was assessed. Sample quadrats from two regions of the UK were available for post priori analysis; a random sample from

  9. A REVIEW OF ASSESSMENTS CONDUCTED ON BIO-ETHANOL AS A TRANSPORTATION FUEL FROM A NET ENERGY, GREENHOUSE GAS, AND ENVIRONMENTAL LIFE CYCLE PERSPECTIVE

    Science.gov (United States)

    Interest in producing ethanol from bio-mass in an attempt to make transportation ecologically sustainable continues to grow. In recent years, a large number of assessments have been conducted to assess the environmental merit of biofuels. Two detailed reviews that looked at the s...

  10. Use of Innovative and Advanced Computer Simulations of Chemical Speciation of Heavy Metals in Soils and Other Environmental Samples

    Directory of Open Access Journals (Sweden)

    Jeske Agnieszka

    2014-10-01

    Full Text Available The article presents several aspects of computer simulations and models of heavy metals speciation in environmental samples. The methods can be effectively used in environmental sciences, soil science, and assessment of mobility and bioavailability of heavy metals in contaminated areas. The article presents all of the methods based on examples, and with interpretation of results. The effect depends on the reliability of data used in models. The results are essential for predicting the fate and behaviour of elements in the environment, and can also be used to develop solubility curves.

  11. A rapid and high-throughput quantum dots bioassay for monitoring of perfluorooctane sulfonate in environmental water samples

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jiong; Wan Yanjian; Li Yuanyuan; Zhang Qiongfang; Xu Shunqing [Minister of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province 430030 (China); Zhu Huijun [Cranfield Health, Cranfield University, Kempston, Bedfordshire, MK43 0AL (United Kingdom); Shu Baihua, E-mail: shubaihua@hotmail.com [Minister of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province 430030 (China)

    2011-05-15

    Currently HPLC/MS is the state of the art tool for environmental/drinking water perfluorooctane sulfonate (PFOS) monitoring. PFOS can bind to peroxisomal proliferator-activated receptor-alpha (PPAR{alpha}), which forms heterodimers with retinoid X receptors (RXRs) and binds to PPAR response elements. In this bioassay free PFOS in water samples competes with immobilized PFOS in ELISA plates for a given amount of PPAR{alpha}-RXR{alpha}. It can be determined indirectly by immobilizing PPAR{alpha}-RXR{alpha}-PFOS complex to another plate coated with PPAR{alpha} antibody and subsequent measuring the level of PPAR{alpha}-RXR{alpha} by using biotin-modified PPAR{alpha}-RXR{alpha} probes-quantum dots-streptavidin detection system. The rapid and high-throughput bioassay demonstrated a detection limit of 2.5 ng L{sup -1} with linear range between 2.5 ng L{sup -1} and 75 ng L{sup -1}. Detection results of environmental water samples were highly consistent between the bioassay and HPLC/MS. - We developed a rapid and high-throughput bioassay for monitoring of PFOS in environmental water samples. - Highlights: > We developed a rapid and high-throughput bioassay for monitoring of PFOS in water. > We detected the PFOS concentration of water samples by two methods. > The bioassay is effective for evaluating PFOS contamination level.

  12. Supercritical Fluid Extraction and Ultra Performance Liquid Chromatography of Respiratory Quinones for Microbial Community Analysis in Environmental and Biological Samples

    Directory of Open Access Journals (Sweden)

    Koichi Fujie

    2012-03-01

    Full Text Available Microbial community structure plays a significant role in environmental assessment and animal health management. The development of a superior analytical strategy for the characterization of microbial community structure is an ongoing challenge. In this study, we developed an effective supercritical fluid extraction (SFE and ultra performance liquid chromatography (UPLC method for the analysis of bacterial respiratory quinones (RQ in environmental and biological samples. RQ profile analysis is one of the most widely used culture-independent tools for characterizing microbial community structure. A UPLC equipped with a photo diode array (PDA detector was successfully applied to the simultaneous determination of ubiquinones (UQ and menaquinones (MK without tedious pretreatment. Supercritical carbon dioxide (scCO2 extraction with the solid-phase cartridge trap proved to be a more effective and rapid method for extracting respiratory quinones, compared to a conventional organic solvent extraction method. This methodology leads to a successful analytical procedure that involves a significant reduction in the complexity and sample preparation time. Application of the optimized methodology to characterize microbial communities based on the RQ profile was demonstrated for a variety of environmental samples (activated sludge, digested sludge, and compost and biological samples (swine and Japanese quail feces.

  13. Supercritical fluid extraction and ultra performance liquid chromatography of respiratory quinones for microbial community analysis in environmental and biological samples.

    Science.gov (United States)

    Hanif, Muhammad; Atsuta, Yoichi; Fujie, Koichi; Daimon, Hiroyuki

    2012-03-05

    Microbial community structure plays a significant role in environmental assessment and animal health management. The development of a superior analytical strategy for the characterization of microbial community structure is an ongoing challenge. In this study, we developed an effective supercritical fluid extraction (SFE) and ultra performance liquid chromatography (UPLC) method for the analysis of bacterial respiratory quinones (RQ) in environmental and biological samples. RQ profile analysis is one of the most widely used culture-independent tools for characterizing microbial community structure. A UPLC equipped with a photo diode array (PDA) detector was successfully applied to the simultaneous determination of ubiquinones (UQ) and menaquinones (MK) without tedious pretreatment. Supercritical carbon dioxide (scCO(2)) extraction with the solid-phase cartridge trap proved to be a more effective and rapid method for extracting respiratory quinones, compared to a conventional organic solvent extraction method. This methodology leads to a successful analytical procedure that involves a significant reduction in the complexity and sample preparation time. Application of the optimized methodology to characterize microbial communities based on the RQ profile was demonstrated for a variety of environmental samples (activated sludge, digested sludge, and compost) and biological samples (swine and Japanese quail feces).

  14. Surveillance and characterisation of Cronobacter spp. in Czech retail food and environmental samples.

    Science.gov (United States)

    Mozrová, V; Břeňová, N; Mrázek, J; Lukešová, D; Marounek, M

    2014-01-01

    Cronobacter spp. (formerly Enterobacter sakazakii) are emerging, opportunistic pathogens that are linked with food-borne infections in neonates and infants. In the present study, 291 samples of food, 36 samples from a dairy farm and 140 samples of dust from vacuum cleaners were examined for the presence of Cronobacter spp. using chromogenic media and biochemical tests. Altogether, 72 Cronobacter spp. strains were isolated in accordance with the reference standard ČSN P ISO/TS 22964 (2006). No Cronobacter spp. strains were detected in 10 samples of infant milk formula or in samples from a dairy farm. Twelve out of 20 positive food samples were dry products. The incidence of Cronobacter spp. in instant and powdered products and spices (12 positive isolates out of 82 samples) was significantly higher than that in other foods (P = 0.002), but lower than that in samples of dust (52 isolates; P < 0.001). The incidence of Cronobacter spp. in dust from restaurants, bars and hotels (13 positive isolates in 20 samples) was significantly higher than that in dust from households (P = 0.010). The polymerase chain reaction assay for the species-specific detection of the rpoB gene was performed in 49 isolates. Thirty-four Cronobacter spp. isolates were identified as Cronobacter sakazakii, nine isolates as Cronobacter malonaticus and one isolate as Cronobacter turicensis.

  15. [Distribution Characteristics of Heavy Metals in Environmental Samples Around Electroplating Factories and the Health Risk Assessment].

    Science.gov (United States)

    Guo, Peng-ran; Lei, Yong-qian; Zhou, Qiao-li; Wang, Chang; Pan, Jia-chuan

    2015-09-01

    This study aimed to investigate the pollution degree and human health risk of heavy metals in soil and air samples around electroplating factories. Soil, air and waste gas samples were collected to measure 8 heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in two electroplating factories, located in Baiyun district of Guangzhou city. Geoaccumulation index and USEPA Risk Assessment Guidance for Superfund (RAGS) were respectively carried out. Results showed that concentrations of Hg and Pb in waste gas and Cr in air samples were higher than limits of the corresponding quality standards, and concentrations of Cd, Hg and Zn in soil samples reached the moderate pollution level. The HQ and HI of exposure by heavy metals in air and soil samples were both lower than 1, indicating that there was no non-carcinogen risk. CRAs and CRCr in soil samples were beyond the maximum acceptable level of carcinogen risk (10(-4)), and the contribution rate of CRCr to TCR was over 81%. CRCr, CRNi and TCR in air samples were in range of 10(-6) - 10(-4), indicating there was possibly carcinogen risk but was acceptable risk. CR values for children were higher than adults in soils, but were higher for adults in air samples. Correlation analysis revealed that concentrations of heavy metals in soils were significantly correlated with these in waste gas samples, and PCA data showed pollution sources of Cd, Hg and Zn in soils were different from other metals.

  16. Fish survey, fishing duration, and other data from gill nets, fyke nets, and other gear from NOAA Ship DISCOVERER and other platforms as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1982-07-25 to 1983-09-23 (NCEI Accession 8700139)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish survey, fishing duration, and other data were collected from gill nets, fyke nets, and other gear from NOAA Ship DISCOVERER and other platforms from 25 July...

  17. Microbial Indicator Profiling of Fresh Produce and Environmental Samples from Farms and Packing Facilities in Northern Mexico.

    Science.gov (United States)

    Heredia, Norma; Caballero, Cindy; Cárdenas, Carmen; Molina, Karina; García, Rafael; Solís, Luisa; Burrowes, Vanessa; Bartz, Faith E; de Aceituno, Anna Fabiszewski; Jaykus, Lee-Ann; García, Santos; Leon, Juan

    2016-07-01

    To compare microbiological indicator and pathogen contamination among different types of fresh produce and environmental samples along the production chain, 636 samples of produce (rinsates from cantaloupe melons, jalapeño peppers, and tomatoes) and environmental samples (rinsates from hands of workers, soil, and water) were collected at four successive steps in the production process (from the field before harvest through the packing facility) on 11 farms in northern Mexico during 2011 and 2012. Samples were assayed for enteric pathogens (Escherichia coli O157:H7, other Shiga toxigenic E. coli, Salmonella, and Listeria monocytogenes) and microbial indicators (coliforms, other E. coli strains, and Enterococcus spp.). Salmonella was the only pathogen detected; it was found in one preharvest jalapeño sample (detection limits: 0.0033 CFU/ml in produce and hand samples, 0.0013 CFU/ml in water, and 0.04 CFU/g in soil). Microbial indicator profiles for produce, worker hands, and soil from jalapeño and tomato farms were similar, but cantaloupe farm samples had higher indicator levels (P coliforms, E. coli, and Enterococcus, respectively, and lower E. coli levels in soil (water from tomato farms, E. coli indicators were significantly more prevalent (70 to 89% of samples were positive; P = 0.01 to 0.02), and geometric mean levels were higher (0.3 to 0.6 log CFU/100 ml) than those in cantaloupe farm water (32 to 38% of samples were positive, geometric mean <1 CFU/100 ml). Microbial indicators were present during all production steps, but prevalence and levels were generally highest at the final on-farm production step (the packing facility) (P < 0.03 for significant comparisons). The finding that microbial contamination on produce farms is influenced by produce type and production step can inform the design of effective approaches to mitigate microbial contamination.

  18. Health and Safety Laboratory environmental quarterly, March 1--June 1, 1976. [Fallout, natural radioactivity, and lead in environmental samples from USA, India, and Taiwan during 1976

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, E.P. Jr.

    1976-07-01

    This report presents current data from the HASL environmental programs, the Air Monitoring Section of the Bhabha Atomic Research Center in India, the Health Physics Section of the Institute of Nuclear Science in Taiwan and the Radiological and Environmental Research Division at Argonne National Laboratory. The initial section consists of interpretive reports and notes on the history of long-range fallout, cesium-137 in Bombay milk, natural and fallout radioactivity in Indian diet, reporting results of radioactivity measurements at near zero levels of sample activity and background, plutonium in soil northeast of the Nevada Test Site, radon levels at the Lloyd, NY regional station, strontium-90 in New York and San Francisco diets through 1975, plutonium-239, 240 in 1974 diet, up-dating stratospheric radionuclide inventories to July 1975 and a revised table of radionuclides. Subsequent sections include tabulations of radionuclide levels in stratospheric air; lead and radionuclides in surface air; strontium-90 in deposition, milk, diet, tap water, and human bone; cesium-137 in Chicago foods in April 1976; and environmental radioactivity surveys for nuclear power plants in North Taiwan. A bibliography of recent publications related to environmental studies is also presented.

  19. Determination of isotopes of uranium and thorium in low-level environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Acena, M.L. (CIEMAT, Inst. de Investigacion Basica, Metrologia. Ed. 3, Madrid (Spain)); Crespo, M.T. (CIEMAT, Inst. de Investigacion Basica, Metrologia. Ed. 3, Madrid (Spain)); Galan, M.P. (CIEMAT, Inst. de Investigacion Basica, Metrologia. Ed. 3, Madrid (Spain)); Gascon, J.L. (CIEMAT, Inst. de Investigacion Basica, Metrologia. Ed. 3, Madrid (Spain))

    1994-01-22

    Different sample treatments and separation procedures are set up and compared for the analysis of uranium and thorium in coal, sediments, water and plant samples. Some considerations about the alpha-spectrometric measurements and the radioactive tracers used as yield determinants of the chemical process are presented. (orig.)

  20. Variation in spatial and temporal incidence of the crustacean pathogen Hematodinium perezi in environmental samples from Atlantic Coastal Bays.

    Science.gov (United States)

    Hanif, Ammar W; Dyson, Whitney D; Bowers, Holly A; Pitula, Joseph S; Messick, Gretchen A; Jagus, Rosemary; Schott, Eric J

    2013-05-04

    Hematodinium perezi, a parasitic dinoflagellate, infects and kills blue crabs, Callinectes sapidus, along the Atlantic and Gulf coasts of the United States. The parasite proliferates within host hemolymph and tissues, and also produces free-swimming biflagellated dinospores that emerge from infected crabs. Infections in C. sapidus recur annually, and it is not known if biotic or environmental reservoirs contribute to reinfection and outbreaks. To address this data gap, a quantitative PCR assay based on the internal transcribed spacer 2 (ITS2) region of H. perezi rRNA genes was developed to asses the temporal and spatial incidence of the parasite in Delaware and Maryland coastal bays. A previously-used PCR assay for H. perezi, based on the small subunit rRNA gene sequence, was found to lack adequate species specificity to discriminate non-Hematodinium sp. dinoflagellate species in environmental samples. A new ITS2-targeted assay was developed and validated to detect H. perezi DNA in sediment and water samples using E. coli carrying the H. perezi rDNA genes. Application of the method to environmental samples identified potential hotspots in sediment in Indian River Inlet, DE and Chincoteague Bay, MD and VA. H. perezi DNA was not detected in co-occurring shrimp or snails, even during an outbreak of the parasite in C. sapidus. H. perezi is present in water and sediment samples in Maryland and Delaware coastal bays from April through November with a wide spatial and temporal variability in incidence. Sampling sites with high levels of H. perezi DNA in both bays share characteristics of silty, organic sediments and low tidal currents. The environmental detection of H. perezi in spring, ahead of peak prevalence in crabs, points to gaps in our understanding of the parasite's life history prior to infection in crabs as well as the mode of environmental transmission. To better understand the H. perezi life cycle will require further monitoring of the parasite in habitats as

  1. A Degradome-Based Polymerase Chain Reaction to Resolve the Potential of Environmental Samples for 2,4-Dichlorophenol Biodegradation.

    Science.gov (United States)

    Ibrahim, Eslam S; Kashef, Mona T; Essam, Tamer M; Ramadan, Mohammed A

    2017-12-01

    A clean way to overcome environmental pollution is biodegradation. In this perspective, at the intersection of biodegradation and metagenomics, the degradome is defined as the totality of genes related to the biodegradation of a certain compound. It includes the genetic elements from both culturable and uncultured microorganisms. The possibility of assessing the biodegradation potential of an environmental samples, using a degradome-based polymerase chain reaction, was explored. 2,4-Dichlorophenol (2,4-DCP) was chosen as a model and the use of tfdB gene as a biodegradation marker was confirmed by bioinformatics study of TfdB protein. Five primer pairs were designed for the detection of different tfdB gene families. A total of 16 environmental samples were collected from Egyptian agricultural soils and wastewaters and tested for the presence of 2,4-DCP. The biodegradation capacity of 2,4-DCP was determined, for all isolated consortia, to reach up to 350 mg/l. Metagenomic DNA was extracted directly from the soil samples while successive 2,4-DCP-degrading microbial communities were enriched, with increasing concentrations of 2,4-DCP, then their DNA was extracted. The extracted DNA was tested for the distribution of the tfdB gene using a degradome-based polymerase chain reaction. tfdB-1 and tfdB-2 were detected in 5 and 9 samples, respectively. However, the co-existence of both genes was detected only in five samples. All tfdB positive samples were capable of 2,4-DCP degradation. The developed approach of assessing the potential of different environments for degrading 2,4-DCP was successfully measured in terms of accuracy (81.25%) and specificity (100%).

  2. Application of a Homogenous Assay for the Detection of 2,4,6-Trinitrotoluene to Environmental Water Samples

    Directory of Open Access Journals (Sweden)

    Ellen R. Goldman

    2005-01-01

    Full Text Available A homogeneous assay was used to detect 2,4,6-trinitrotoluene (TNT spiked into environmental water samples. This assay is based on changes in fluorescence emission intensity when TNT competitively displaces a fluorescently labeled, TNT analog bound to an anti-TNT antibody. The effectiveness of the assay was highly dependent on the source of the sample being tested. As no correlation between pH and assay performance was observed, ionic strength was assumed to be the reason for variation in assay results. Addition of 10x phosphate-buffered saline to samples to increase their ionic strength to that of our standard laboratory buffer (about 0.17 M significantly improved the range over which the assay functioned in several river water samples.

  3. VAPOR PRESSURE ISOTOPE EFFECTS IN THE MEASUREMENT OF ENVIRONMENTAL TRITIUM SAMPLES.

    Energy Technology Data Exchange (ETDEWEB)

    Kuhne, W.

    2012-12-03

    Standard procedures for the measurement of tritium in water samples often require distillation of an appropriate sample aliquot. This distillation process may result in a fractionation of tritiated water and regular light water due to the vapor pressure isotope effect, introducing either a bias or an additional contribution to the total tritium measurement uncertainty. The magnitude of the vapor pressure isotope effect is characterized as functions of the amount of water distilled from the sample aliquot and the heat settings for the distillation process. The tritium concentration in the distillate is higher than the tritium concentration in the sample early in the distillation process, it then sharply decreases due to the vapor pressure isotope effect and becomes lower than the tritium concentration in the sample, until the high tritium concentration retained in the boiling flask is evaporated at the end of the process. At that time, the tritium concentration in the distillate again overestimates the sample tritium concentration. The vapor pressure isotope effect is more pronounced the slower the evaporation and distillation process is conducted; a lower heat setting during the evaporation of the sample results in a larger bias in the tritium measurement. The experimental setup used and the fact that the current study allowed for an investigation of the relative change in vapor pressure isotope effect in the course of the distillation process distinguish it from and extend previously published measurements. The separation factor as a quantitative measure of the vapor pressure isotope effect is found to assume values of 1.034 {+-} 0.033, 1.052 {+-} 0.025, and 1.066 {+-} 0.037, depending on the vigor of the boiling process during distillation of the sample. A lower heat setting in the experimental setup, and therefore a less vigorous boiling process, results in a larger value for the separation factor. For a tritium measurement in water samples, this implies that

  4. Area G perimeter surface-soil and single-stage water sampling: Environmental surveillance for fiscal year 1993

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, R.; Childs, M.; Rivera-Dirks, C.; Coriz, F.

    1995-07-01

    Area G, in Technical Area 54, has been the principle facility at Los Alamos National Laboratory for the storage and disposal of low-level and transuranic (TRU) radioactive wastes since 1957. The current environmental investigation consisted of ESH-19 personnel who collected soil and single-stage water samples around the perimeter of Area G to characterize possible contaminant movement through surface-water runoff. These samples were analyzed for tritium, total uranium, isotopic plutonium, americium-241 (soil only), and cesium 137. The metals, mercury, lead, and barium, were analyzed using x-ray fluorescence.

  5. Determination of platinum and palladium in environmental samples by graphite furnace atomic absorption spectrometry after separation on dithizone sorbent.

    Science.gov (United States)

    Chwastowska, J; Skwara, W; Sterlińska, E; Pszonicki, L

    2004-09-08

    A graphite furnace atomic absorption method of platinum and palladium determination after their separation from environmental samples has been presented. The samples were digested by aqua regia and the analyte elements were separated on the dithizone sorbent. The procedure of sorbent preparation was described and their properties were established. Two various procedures of elution by thiourea and concentrated nitric acid were described and discussed. The low limit of detection was established as 1ngg(-1) for platinum and 0.2ngg(-1) for palladium. There was also investigated the behaviour of platinum and palladium introduced into the soil in various chemical forms.

  6. Quantitative Comparisons of 16S rRNA Gene Sequence Libraries from Environmental Samples

    Science.gov (United States)

    Singleton, David R.; Furlong, Michelle A.; Rathbun, Stephen L.; Whitman, William B.

    2001-01-01

    To determine the significance of differences between clonal libraries of environmental rRNA gene sequences, differences between homologous coverage curves, CX(D), and heterologous coverage curves, CXY(D), were calculated by a Cramér-von Mises-type statistic and compared by a Monte Carlo test procedure. This method successfully distinguished rRNA gene sequence libraries from soil and bioreactors and correctly failed to find differences between libraries of the same composition. PMID:11526051

  7. Quantitative Comparisons of 16S rRNA Gene Sequence Libraries from Environmental Samples

    OpenAIRE

    Singleton, David R.; Furlong, Michelle A.; Rathbun, Stephen L; William B. Whitman

    2001-01-01

    To determine the significance of differences between clonal libraries of environmental rRNA gene sequences, differences between homologous coverage curves, CX(D), and heterologous coverage curves, CXY(D), were calculated by a Cramér-von Mises-type statistic and compared by a Monte Carlo test procedure. This method successfully distinguished rRNA gene sequence libraries from soil and bioreactors and correctly failed to find differences between libraries of the same composition.

  8. Dynamic Flow-through Methods for Metal Fractionation in Environmental Solid Samples

    DEFF Research Database (Denmark)

    Miró, Manuel; Hansen, Elo Harald; Petersen, Roongrat

    of elements is quite insufficient to estimate their physicochemical mobility, potential bioavailability, and, consequently, toxicity. Within the last two decades, batchwise equilibrium-based single or sequential extraction schemes have been consolidated as analytical tools for fractionation analyses to assess...... occurring processes always take place under dynamic conditions, recent trends have been focused on the development of alternative flow-through dynamic methods aimed at mimicking environmental events more correctly than their classical extraction counterparts. In this lecture particular emphasis is paid...

  9. Discovery of Aspergillus frankstonensis sp nov during environmental sampling for animal and human fungal pathogens

    DEFF Research Database (Denmark)

    Talbot, Jessica J.; Houbraken, Jos; Frisvad, Jens Christian

    2017-01-01

    . nov.) and 30% were other species (30%). Seven pathogenic ASF species known to cause disease in humans and animals (A. felis-clade, A. fischeri, A. thermomutatus, A. lentulus, A. laciniosus A. fumisynne-matus, A. hiratsukae) comprised 25% of isolates overall. AVSC species were only isolated from...... to pathogenic species in ASF in Australia appears to be high, but there was no evidence of direct environmental exposure to AVSC species in areas where humans and cats cohabitate....

  10. WaveNet

    Science.gov (United States)

    2015-10-30

    Coastal Inlets Research Program WaveNet WaveNet is a web-based, Graphical-User-Interface ( GUI ) data management tool developed for Corps coastal...generates tabular and graphical information for project planning and design documents. The WaveNet is a web-based GUI designed to provide users with a...data from different sources, and employs a combination of Fortran, Python and Matlab codes to process and analyze data for USACE applications

  11. Use of lectin-magnetic separation (LMS) for detecting Toxoplasma gondii oocysts in environmental water samples.

    Science.gov (United States)

    Harito, Jemere Bekele; Campbell, Andrew T; Tysnes, Kristoffer R; Robertson, Lucy J

    2017-12-15

    Proof-of-principle of lectin-magnetic separation (LMS) for isolating Toxoplasma oocysts (pre-treated with 0.5% acidified pepsin (AP)) from water for subsequent detection by microscopy or molecular methods has been shown. However, application of this technique in the routine water-analysis laboratory requires that the method is tested, modified, and optimized. The current study describes attempts to apply the LMS technique on supernatants from water samples previously analyzed for contamination with Cryptosporidium and Giardia using standard methods, and the supernatant following immunomagnetic separation (IMS) retained. Experiments on AP-treatment of Toxoplasma oocysts in situ in such samples demonstrated that overnight incubation at 37 °C was adequate, but excess AP had to be removed before continuing to LMS; neutralization in sodium hydroxide and a single wash step was found to be suitable. Mucilaginous material in post-IMS samples that had been stored at room temperature without washing, which was found to be probably an exudate from bacterial and fungal overgrowth, hampered the isolation of T. gondii oocysts by LMS beads. For detection, microscopy was successful only for clean samples, as debris occluded viewing in dirtier samples. Although qPCR was successful, for some samples non-specific inhibition occurred, as demonstrated by inhibition of an internal amplification control in the qPCR reaction. For some, but not all, samples this could be addressed by dilution. Finally, the optimized methodology was used for a pilot project in which 23 post-IMS water sample concentrates were analyzed. Of these, only 20 provided interpretable results (without qPCR inhibition) of which one sample was positive, and confirmed by sequencing of PCR product, indicating that Toxoplasma oocysts occur in Norwegian drinking water samples. In conclusion, we suggest that post-IMS samples may be suitable for analysis for Toxoplasma oocysts using LMS, only if freshly processed or

  12. A portable methane sampling system for radiocarbon-based bioportion measurements and environmental CH4 sourcing studies

    Science.gov (United States)

    Palonen, V.; Uusitalo, J.; Seppälä, E.; Oinonen, M.

    2017-07-01

    Radiocarbon measurements can be used to deduce the proportion of renewable to fossil carbon in materials. While these biofraction measurements are performed routinely on solid and liquid substances, measurements of gaseous samples, such as methane, are still scarce. As a pioneering effort, we have developed a field-capable sampling system for the selective capture of CH4 for radiocarbon-concentration measurements. The system allows for biofraction measurements of methane by accelerator mass spectrometry. In environmental research, radiocarbon measurements of methane can be used for fingerprinting different sources of methane emissions. In metrology and industry, biofraction measurements can be utilized to characterize biogas/natural gas mixtures within gas-line networks. In this work, the portable sampling system is described in detail and reference measurements of biofractions of gaseous fuel samples are presented. Low-concentration (1-ppm-CH4) sampling for environmental applications appears feasible but has not been fully tested at present. This development allows for multitude of future applications ranging from Arctic methane emissions to biogas insertion to gas networks.

  13. Fluorescence spectrophotometer analysis of polycyclic aromatic hydrocarbons in environmental samples based on solid phase extraction using molecularly imprinted polymer.

    Science.gov (United States)

    Krupadam, Reddithota J; Bhagat, Bhagyashree; Wate, Satish R; Bodhe, Ghanshyam L; Sellergren, Borje; Anjaneyulu, Yerramilli

    2009-04-15

    A molecularly imprinted polymer (MIP) was synthesized using a polycyclic aromatic hydrocarbon (PAH) standard as a template, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, and acetonitrile as a porogen. This polymer was used as a solid phase adsorbent for the quantitative enrichment of PAHs in coastal sediments, atmospheric particulates, and industrial effluents. The MIP selective adsorption capacity for PAHs started reducing when the chemical oxygen demand (COD) and total dissolved solids (TDS) was more than 800 mg L(-1) in the targeted environmental samples. The adsorption stability of the MIP was tested by the consecutive contact of environmental samples, and it was shown that the performance of the MIP did not vary after 10 enrichments and desorption cycles. Recoveries of eight PAH compounds, extracted from 10 g of coastal sediments and 1 L of industrial effluent spiked with 10 microL of standard PAHs, showed recoveries between 85 and 96%. The fluorescence spectrophotometer limit of detection of PAHs varied from 10 to 30 etag L(-1) in industrial effluent and from 0.1 to 2.9 etag kg(-1) in solid samples (coastal sediment and atmospheric particulates), and this indicates that the environmental analytical method is significantly sensitive, when compared with other commonly used methods such as gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry.

  14. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt

    1991-01-01

    This paper describes how Coloured Petri Nets (CP-nets) have been developed — from being a promising theoretical model to being a full-fledged language for the design, specification, simulation, validation and implementation of large software systems (and other systems in which human beings and...... use of CP-nets — because it means that the function representation and the translations (which are a bit mathematically complex) no longer are parts of the basic definition of CP-nets. Instead they are parts of the invariant method (which anyway demands considerable mathematical skills...

  15. Game Coloured Petri Nets

    DEFF Research Database (Denmark)

    Westergaard, Michael

    2006-01-01

    This paper introduces the notion of game coloured Petri nets. This allows the modeler to explicitly model what parts of the model comprise the modeled system and what parts are the environment of the modeled system. We give the formal definition of game coloured Petri nets, a means of reachability...... analysis of this net class, and an application of game coloured Petri nets to automatically generate easy-to-understand visualizations of the model by exploiting the knowledge that some parts of the model are not interesting from a visualization perspective (i.e. they are part of the environment...

  16. Programming NET Web Services

    CERN Document Server

    Ferrara, Alex

    2007-01-01

    Web services are poised to become a key technology for a wide range of Internet-enabled applications, spanning everything from straight B2B systems to mobile devices and proprietary in-house software. While there are several tools and platforms that can be used for building web services, developers are finding a powerful tool in Microsoft's .NET Framework and Visual Studio .NET. Designed from scratch to support the development of web services, the .NET Framework simplifies the process--programmers find that tasks that took an hour using the SOAP Toolkit take just minutes. Programming .NET

  17. Annotating Coloured Petri Nets

    DEFF Research Database (Denmark)

    Lindstrøm, Bo; Wells, Lisa Marie

    2002-01-01

    -net. An example of such auxiliary information is a counter which is associated with a token to be able to do performance analysis. Modifying colour sets and arc inscriptions in a CP-net to support a specific use may lead to creation of several slightly different CP-nets – only to support the different uses...... a method which makes it possible to associate auxiliary information, called annotations, with tokens without modifying the colour sets of the CP-net. Annotations are pieces of information that are not essential for determining the behaviour of the system being modelled, but are rather added to support...

  18. Environmental contaminants in water, sediment and biological samples from Playa Lakes in southeastern New Mexico - 1992

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Sediment, water, bird tissue, and invertebrates were collected from 10 playa lakes in Southeastern New Mexico in 1991 and 1992. These samples were analyzed for a...

  19. , as demonstrated for the determination of nickel in environmental and biological samples

    DEFF Research Database (Denmark)

    Wang, Jianhua; Hansen, Elo Harald

    2001-01-01

    is demonstrated for the determination of trace level concentrations of nickel. The column is loaded with a defined volume of SP Sephadex C-25 cation-exchange resin beads and subsequently exposed to a metered volume of sample solution. The analyte loaded beads are afterwards eluted with 30mul of diluted nitric.......1 and a detection limit of 10.2ng/l along with a sampling frequency of 12 s/h were obtained, which are at the same levels as those for the previously described procedure without elution. The present approach was validated by determination of the nickel contents in two certified reference materials, an industrial...... waste water sample and a human urine sample....

  20. Evaluation of PCR, DNA hybridization and immunomagnetic separation - PCR for detection of Burkholderia mallei in artificially inoculated environmental samples.

    Science.gov (United States)

    Merwyn, S; Kumar, S; Agarwal, G S; Rai, G P

    2010-06-01

    Glanders is highly contagious disease of equines, caused by Burkholderia mallei. The disease though rare, can be transmitted to humans. Here, we report a strategy for rapid detection of B. mallei from environmental samples. Different bacteriological media were evaluated and brain heart infusion broth medium with selective supplements (BHIB-SS) of penicillin (200 U/ml) and crystal violet (1:10,00000) was found to support the maximum growth of B. mallei even in the presence of other bacteria like Escherichia coli and Staphylococcus aureus. A polymerase chain reaction (PCR) and a DNA hybridization method was standardized for 823 bp specific dNA sequence of B. mallei. To enable the quicker and direct enrichment of B. mallei bacteria from environmental samples, an immunomagnetic separation (IMS) method was also standardized. Water, husk, grass and gram samples were artificially contaminated by B. mallei bacteria and after enrichment of B. mallei in BHIB-SS, detection was carried out by PCR and DNA hybridization. PCR was found to be a better method of the two with a detection limit of 10(4)-10(6) CFU/ml (6 h enrichment in BHIB-SS) in water and other particulate matrices. Detection by PCR in the above samples without enrichment in BHIBSS was carried out following IMS where the detection limit was about 1-2 log higher than PCR following enrichment in BHIB-SS. We recommend PCR for 823 bp for detection of B. mallei from environmental samples either following enrichment in BHIB-SS or IMS. IMS-PCR method may be preferred in situations where numbers of B. mallei bacteria are expected to be high and results are required in short time.

  1. Determination of total mercury for marine environmental monitoring studies by solid sampling continuum source high resolution atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mandjukov, Petko; Orani, Anna Maria; Han, Eunmi; Vassileva, Emilia, E-mail: e.vasileva-veleva@iaea.org

    2015-01-01

    The most critical step in almost all commonly used analytical procedures for Hg determination is the sample preparation due to its extreme volatility. One of the possible solutions of this problem is the application of methods for direct analysis of solid samples. The possibilities for solid sampling high resolution continuum source atomic absorption spectrometry (HR CS AAS) determination of total mercury in various marine environmental samples e.g. sediments and biota are object of the present study. The instrumental parameters were optimized in order to obtain reproducible and interference free analytical signal. A calibration technique based on the use of solid standard certified reference materials similar to the nature of the analyzed sample was developed and applied to various CRMs and real samples. This technique allows simple and reliable evaluation of the uncertainty of the result and the metrological characteristics of the method. A validation approach in line with the requirements of ISO 17025 standard and Eurachem guidelines was followed. With this in mind, selectivity, working range (0.06 to 25 ng for biota and 0.025 to 4 ng for sediment samples, expressed as total Hg) linearity (confirmed by Student's t-test), bias (1.6–4.3%), repeatability (4–9%), reproducibility (9–11%), and absolute limit of detection (0.025 ng for sediment, 0.096 ng for marine biota) were systematically assessed using solid CRMs. The relative expanded uncertainty was estimated at 15% for sediment sample and 8.5% for marine biota sample (k = 2). Demonstration of traceability of measurement results is also presented. The potential of the proposed analytical procedure, based on solid sampling HR CS AAS technique was demonstrated by direct analysis of sea sediments form the Caribbean region and various CRMs. Overall, the use of solid sampling HR CS AAS permits obtaining significant advantages for the determination of this complex analyte in marine samples, such as

  2. Prevalence of Naegleria fowleri in Environmental Samples from Northern Part of India.

    Directory of Open Access Journals (Sweden)

    Ashutosh Panda

    Full Text Available Naegleria fowleri the causative agent of Primary Amoebic Meningoencephalitis, is ubiquitously distributed worldwide in various warm aquatic environments and soil habitats. The present study reports on the presence of Naegleria spp. in various water bodies present in Rohtak and Jhajjar district, of state Haryana, India. A total of 107 water reservoirs were screened from summer till autumn (2012 and 2013. In order to isolate Naegleria spp. from the collected water samples, the water samples were filtered and the trapped debris after processing were transferred to non-nutrient agar plates already seeded with lawn culture of Escherichia coli. Out of total 107 water samples, 43 (40% samples were positive by culture for free living amoeba after incubation for 14 days at 37°C. To identify the isolates, the ITS1, 5.8SrDNA and ITS2 regions were targeted for PCR assay. Out of total 43 positive samples, 37 isolates were positive for Naegleria spp. using genus specific primers and the most frequently isolated species was Naegleria australiensis. Out of 37 Naegleria spp. positive isolates, 1 isolate was positive for Naegleria fowleri. The sequence analysis revealed that the Naegleria fowleri strain belonged to Type 2.

  3. Prevalence of Naegleria fowleri in Environmental Samples from Northern Part of India.

    Science.gov (United States)

    Panda, Ashutosh; Khalil, Shehla; Mirdha, Bijay Ranjan; Singh, Yogita; Kaushik, Samander

    2015-01-01

    Naegleria fowleri the causative agent of Primary Amoebic Meningoencephalitis, is ubiquitously distributed worldwide in various warm aquatic environments and soil habitats. The present study reports on the presence of Naegleria spp. in various water bodies present in Rohtak and Jhajjar district, of state Haryana, India. A total of 107 water reservoirs were screened from summer till autumn (2012 and 2013). In order to isolate Naegleria spp. from the collected water samples, the water samples were filtered and the trapped debris after processing were transferred to non-nutrient agar plates already seeded with lawn culture of Escherichia coli. Out of total 107 water samples, 43 (40%) samples were positive by culture for free living amoeba after incubation for 14 days at 37°C. To identify the isolates, the ITS1, 5.8SrDNA and ITS2 regions were targeted for PCR assay. Out of total 43 positive samples, 37 isolates were positive for Naegleria spp. using genus specific primers and the most frequently isolated species was Naegleria australiensis. Out of 37 Naegleria spp. positive isolates, 1 isolate was positive for Naegleria fowleri. The sequence analysis revealed that the Naegleria fowleri strain belonged to Type 2.

  4. A review on speciation of iodine-129 in the environmental and biological samples

    DEFF Research Database (Denmark)

    Hou, Xiaolin; Hansen, Violeta; Aldahan, Ala

    2009-01-01

    plants, the I-129/I-127 ratios have being reached to values of 10(-10) to 10(-4) in the environment from 10(-12) in the pre-nuclear era. In this article, we review the occurrence, sources, inventory, and concentration level of I-129 in environment and the method for speciation analysis of I-129...... in the environment. Measurement techniques for the determination of I-129 are presented and compared. An overview of applications of I-129 speciation in various scientific disciplines such as radiation protection, waste depository, and environmental sciences is given. In addition, the bioavailability and radiation...

  5. Real-time PCR to supplement gold-standard culture-based detection of Legionella in environmental samples.

    Science.gov (United States)

    Collins, S; Jorgensen, F; Willis, C; Walker, J

    2015-10-01

    Culture remains the gold-standard for the enumeration of environmental Legionella. However, it has several drawbacks including long incubation and poor sensitivity, causing delays in response times to outbreaks of Legionnaires' disease. This study aimed to validate real-time PCR assays to quantify Legionella species (ssrA gene), Legionella pneumophila (mip gene) and Leg. pneumophila serogroup-1 (wzm gene) to support culture-based detection in a frontline public health laboratory. Each qPCR assay had 100% specificity, excellent sensitivity (5 GU/reaction) and reproducibility. Comparison of the assays to culture-based enumeration of Legionella from 200 environmental samples showed that they had a negative predictive value of 100%. Thirty eight samples were positive for Legionella species by culture and qPCR. One hundred samples were negative by both methods, whereas 62 samples were negative by culture but positive by qPCR. The average log10 increase between culture and qPCR for Legionella spp. and Leg. pneumophila was 0·72 (P = 0·0002) and 0·51 (P = 0·006), respectively. The qPCR assays can be conducted on the same 1 l water sample as culture thus can be used as a supplementary technique to screen out negative samples and allow more rapid indication of positive samples. The assay could prove informative in public health investigations to identify or rule out sources of Legionella as well as to specifically identify Leg. pneumophila serogroup 1 in a timely manner not possible with culture. © 2015 The Society for Applied Microbiology.

  6. Environmental

    Directory of Open Access Journals (Sweden)

    Sawsan M. Aboul Ezz

    2014-01-01

    Full Text Available Rotifers are one of the most common, abundant components of plankton in the coastal waters of the Mediterranean Sea, which means that they can be used as bio-indicators and provide useful information on the long-term dynamics of the El-Mex Bay ecosystem. Rotifera species were quantitatively and qualitatively assessed in the El-Mex Bay, west of Alexandria at eight stations to study spatial, temporal, dominance, and abundance of the rotifer community and their relation with changes in environmental conditions. Samples were collected seasonally from autumn 2011 to autumn 2012. Ecological parameters were determined and correlated with total rotifers abundance to gain information about the forces that structure the rotifer community in this dynamic environment. A total of 38 rotifer species were identified belonging to 16 genera within 12 families and 3 orders under one class and contributed about 12.1% of the total zooplankton in the study area with an average of 1077 specimens/m3. Maximum density was observed in summer 2012 with an average of 1445 specimens/m3. During autumn 2011 rotifers appeared in low density (434 specimens/m3. The predominant species Ascomorpha saltans, Brachionus urceolaris, Synchaeta oblonga, Synchaeta okai, Synchaeta pectinata and Synchaeta tremula were recorded in all study stations of the bay. Salinity, temperature, depth, and chlorophyll-a concentration were the most important environmental factors co-related with the abundance of rotifers in the El-Mex Bay. A significant positive correlation between the total rotifer abundance and chlorophyll-a was observed during winter 2012 and summer 2012 (r = 0.763 and r = 0.694, respectively, at p ⩽ 0.05.

  7. Environmental impacts of waste produced from processing of different uraniferous rock samples

    Directory of Open Access Journals (Sweden)

    Ibrahim E. El Aassy

    2016-07-01

    Full Text Available Radon exhalation rates from five studied laboratory waste samples resulted from five different sedimentary rock types named sandy dolostone, siltstone –two samples-, marly claystone and black shale were measured using ‘‘Sealed Can technique”. These rates were found to vary between 0.005 and 0.015 Bq m−2 h−1. A positive correlation was found between the radon exhalation rates and the radium activities. The emanation coefficients were calculated for these laboratory waste samples which varied between 0.0004 and 0.0007 according to the physical and chemical characterize of the wastes. These results are partially in accordance with autonite acid leached tailings on laboratory scale (USA. These results led us to pay attention about the effect and impact of these wastes on the environment.

  8. Next-generation sequencing for rodent barcoding: species identification from fresh, degraded and environmental samples.

    Directory of Open Access Journals (Sweden)

    Maxime Galan

    Full Text Available Rodentia is the most diverse order among mammals, with more than 2,000 species currently described. Most of the time, species assignation is so difficult based on morphological data solely that identifying rodents at the specific level corresponds to a real challenge. In this study, we compared the applicability of 100 bp mini-barcodes from cytochrome b and cytochrome c oxidase 1 genes to enable rodent species identification. Based on GenBank sequence datasets of 115 rodent species, a 136 bp fragment of cytochrome b was selected as the most discriminatory mini-barcode, and rodent universal primers surrounding this fragment were designed. The efficacy of this new molecular tool was assessed on 946 samples including rodent tissues, feces, museum samples and feces/pellets from predators known to ingest rodents. Utilizing next-generation sequencing technologies able to sequence mixes of DNA, 1,140 amplicons were tagged, multiplexed and sequenced together in one single 454 GS-FLX run. Our method was initially validated on a reference sample set including 265 clearly identified rodent tissues, corresponding to 103 different species. Following validation, 85.6% of 555 rodent samples from Europe, Asia and Africa whose species identity was unknown were able to be identified using the BLASTN program and GenBank reference sequences. In addition, our method proved effective even on degraded rodent DNA samples: 91.8% and 75.9% of samples from feces and museum specimens respectively were correctly identified. Finally, we succeeded in determining the diet of 66.7% of the investigated carnivores from their feces and 81.8% of owls from their pellets. Non-rodent species were also identified, suggesting that our method is sensitive enough to investigate complete predator diets. This study demonstrates how this molecular identification method combined with high-throughput sequencing can open new realms of possibilities in achieving fast, accurate and inexpensive

  9. Spectrophotometric determination of Sudan Blue II in environmental samples after dispersive liquid-liquid microextraction

    Directory of Open Access Journals (Sweden)

    Yunus Emre Unsal

    2014-01-01

    Full Text Available A dispersive liquid-liquid microextraction procedure coupled to spectrophotometry is described for the determination of the trace levels of Sudan Blue II. Analytical parameters, such as pH, volume of extraction solvent (carbon tetrachloride, volume of dispersant (ethanol, volume of sample, and extraction time, were optimized. Matrix effects were also investigated. Preconcentration factor was found to be 200. Detection limit and relative standard deviation (RSD were 0.55 µg L-1 and 3.9%, respectively. The procedure was successfully used for the determination of trace levels of Sudan Blue II in food, ink, antifreeze, and industrial waste-water samples.

  10. A new approach in separating microplastics from environmental samples based on their electrostatic behavior.

    Science.gov (United States)

    Felsing, Stefanie; Kochleus, Christian; Buchinger, Sebastian; Brennholt, Nicole; Stock, Friederike; Reifferscheid, Georg

    2017-11-16

    Numerous studies on microplastics (MPs; Ø recovery achieved with this method was as high as nearly 100% for each type of material. The method was then tested on plastic particles of different shapes and types isolated from the Rhine River. These were successfully electroseparated from the four materials, which demonstrated the utility of this method. Its advantages include the simplified handling and preparation of different field samples as well as a much shorter processing time, because after the last separation step there is hardly any biological material remaining in the sample fraction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Development of a solid-phase extraction coupling chemiluminescent enzyme immunoassay for determination of organophosphorus pesticides in environmental water samples.

    Science.gov (United States)

    Xu, Zhen-Lin; Sun, Wen-Jia; Yang, Jin-Yi; Jiang, Yue-Ming; Campbell, Katrina; Shen, Yu-Dong; Lei, Hong-Tao; Zeng, Dao-Ping; Wang, Hong; Sun, Yuan-Ming

    2012-03-07

    Solid-phase extraction (SPE) and direct competitive chemiluminescence enzyme immunoassay (dcCL-EIA) were combined for the detection of organophosphorus pesticides (OPs) in environmental water samples. dcCL-EIA based on horseradish peroxidase labeled with a broad-specificity monoclonal antibody against OPs was developed, and the effects of several physicochemical parameters on dcCL-EIA performance were studied. SPE was used for the pretreatment of water samples to remove interfering substances and to concentrate the OP analytes. The coupling of SPE and dcCL-EIA can detect seven OPs (parathion, coumaphos, phoxim, quinalphos, triazophos, dichlofenthion, and azinphos-ethyl) with the limit of quantitation below 0.1 ng/mL. The recoveries of OPs from spiked water samples ranged from 62.5% to 131.7% by SPE-dcCL-EIA and 69.5% to 112.3% by SPE-HPLC-MS/MS. The screening of OP residues in real-world environmental water samples by the developed SPE-dcCL-EIA and their confirmatory analysis using SPE-HPLC-MS/MS demonstrated that the assay is ideally suited as a monitoring method for OP residues prior to chromatographic analysis.

  12. Potential application of superparamagnetic nanoparticles for extraction of bacterial genomic DNA from contaminated food and environmental samples.

    Science.gov (United States)

    Basu, Semanti; Chatterjee, Saptarshi; Bandyopadhyay, Arghya; Sarkar, Keka

    2013-03-15

    Isolation of high-molecular-weight DNA is essential for many molecular biology applications. Owing to the presence of polymerase chain reaction (PCR) inhibitors, there is a scarcity of suitable protocols for PCR-ready DNA extraction from food and natural environments. The conventional chemical methods of DNA extraction are time consuming and laborious and the yield is very low. Thus the aim of this research was to develop a simple, rapid, cost-effective method of genomic DNA extraction from food (milk and fruit juice) and environmental (pond water) samples and to detect bacterial contaminants present in those samples. This approach is efficient for both Gram-positive and Gram-negative bacteria from all the studied samples. Herein super paramagnetic bare iron oxide nanoparticles were implemented for bacterial genomic DNA isolation. The method was also compared to the conventional phenol-chloroform method in the context of quality, quantity and timing process. This method took only half an hour or less to obtain high-molecular-weight purified DNA from minimum bacterial contamination. Additionally, the method was directly compatible to PCR amplification. The problem of availability of suitable generalized methods for DNA isolation from various samples including food and environmental has been solved by a nanobiotechnological approach that may prove to be extremely useful in biotechnological applications. © 2012 Society of Chemical Industry.

  13. Applications of High Resolution Laser Induced Breakdown Spectroscopy for Environmental and Biological Samples

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z [ORNL; Labbe, Nicole [ORNL; Wagner, Rebekah J. [Pennsylvania State University, University Park, PA

    2013-01-01

    This chapter details the application of LIBS in a number of environmental areas of research such as carbon sequestration and climate change. LIBS has also been shown to be useful in other high resolution environmental applications for example, elemental mapping and detection of metals in plant materials. LIBS has also been used in phytoremediation applications. Other biological research involves a detailed understanding of wood chemistry response to precipitation variations and also to forest fires. A cross-section of Mountain pine (pinceae Pinus pungen Lamb.) was scanned using a translational stage to determine the differences in the chemical features both before and after a fire event. Consequently, by monitoring the elemental composition pattern of a tree and by looking for abrupt changes, one can reconstruct the disturbance history of a tree and a forest. Lastly we have shown that multivariate analysis of the LIBS data is necessary to standardize the analysis and correlate to other standard laboratory techniques. LIBS along with multivariate statistical analysis makes it a very powerful technology that can be transferred from laboratory to field applications with ease.

  14. Net zero water

    CSIR Research Space (South Africa)

    Lindeque, M

    2013-01-01

    Full Text Available Is it possible to develop a building that uses a net zero amount of water? In recent years it has become evident that it is possible to have buildings that use a net zero amount of electricity. This is possible when the building is taken off...

  15. SolNet

    DEFF Research Database (Denmark)

    Jordan, Ulrike; Vajen, Klaus; Bales, Chris

    2014-01-01

    SolNet, founded in 2006, is the first coordinated International PhD education program on Solar Thermal Engineering. The SolNet network is coordinated by the Institute of Thermal Engineering at Kassel University, Germany. The network offers PhD courses on solar heating and cooling, conference...

  16. Kunstige neurale net

    DEFF Research Database (Denmark)

    Hørning, Annette

    1994-01-01

    Artiklen beskæftiger sig med muligheden for at anvende kunstige neurale net i forbindelse med datamatisk procession af naturligt sprog, specielt automatisk talegenkendelse.......Artiklen beskæftiger sig med muligheden for at anvende kunstige neurale net i forbindelse med datamatisk procession af naturligt sprog, specielt automatisk talegenkendelse....

  17. Environmental monitoring of fluoride emissions using precipitation, dust, plant and soil samples.

    Science.gov (United States)

    Franzaring, J; Hrenn, H; Schumm, C; Klumpp, A; Fangmeier, A

    2006-11-01

    A pollution gradient was observed in precipitation, plants and soils sampled at different locations around a fluoride producing chemical plant in Germany. In all samples the influence of emissions was discernible up to a distance of 500 m from the plant. However, fluoride concentrations in plant bioindicators (leaves of birch and black berry) and in bulk precipitation showed a more pronounced relationship with the distance from the source than fluoride concentrations in soil. Vegetables sampled in the vicinity of the plant also had elevated concentrations of fluoride, but only the consumption of larger quantities of this material would lead to exceedances of recommended daily F-intake. The present study did not indicate the existence of low phytotoxicity thresholds for fluoride in the plant species used in the study. Even at very high fluoride concentrations in leaf tissue (963 ppm) plants did not show injury due to HF. Dust sampling downwind of the chemical plant confirmed that particulate fluoride was of minor importance in the study area.

  18. Metagenomic analyses of novel viruses and plasmids from a cultured environmental sample of hyperthermophilic neutrophiles

    DEFF Research Database (Denmark)

    Garrett, Roger Antony; Prangishvili, David; Shah, Shiraz Ali

    2010-01-01

    ), and derive apparently from archaeal viruses HAV1 and HAV2. Genomic DNA was obtained from samples enriched in filamentous and tadpole-shaped virus-like particles respectively. They yielded few significant matches in public sequence databases reinforcing, further, the wide diversity of archaeal viruses...

  19. Modification of the mycotoxin deoxynivalenol using microorganisms isolated from environmental samples

    Science.gov (United States)

    The trichothecene mycotoxin deoxynivalenol (DON) is a common contaminant of wheat, barley, and maize. New strategies are needed to reduce or eliminate DON in feed and food products. Microorganisms from plant and soil samples collected in Blacksburg, VA, USA, were screened by incubation in a mineral ...

  20. Measurement of the tritium concentration in the fractionated distillate from environmental water samples.

    Science.gov (United States)

    Atkinson, Robert; Eddy, Teresa; Kuhne, Wendy; Jannik, Tim; Brandl, Alexander

    2014-09-01

    Standard procedures for the measurement of tritium in water samples often require distillation of an appropriate sample aliquot. This distillation process may result in a fractionation of tritiated water and regular light water due to the vapor pressure isotope effect, introducing either a bias or an additional contribution to the total tritium measurement uncertainty. The current study investigates the relative change in vapor pressure isotope effect in the course of the distillation process, distinguishing it from and extending previously published measurements. The separation factor as a quantitative measure of the vapor pressure isotope effect is found to assume values of 1.04 ± 0.036, 1.05 ± 0.026, and 1.07 ± 0.038, depending on the vigor of the boiling process during distillation of the sample. A lower heat setting in the experimental setup, and therefore a less vigorous boiling process, results in a larger value for the separation factor. For a tritium measurement in water samples where the first 5 mL are discarded, the tritium concentration could be underestimated by 4-7%. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Reliable determination of 237Np in environmental solid samples using 242Pu as a potential tracer

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2011-01-01

    experimental conditions. Disulfite-8M HNO3 was selected as a redox pair for valence adjustment to Np(IV) and the tetravalent Np in the sample solution was demonstrated to be stabilized for up to 5 days under 3°C. The analytical results for reference materials showed a good agreement with the expected values...

  2. Determination of extremely low (236)U/(238)U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry using high-efficiency sample introduction.

    Science.gov (United States)

    Boulyga, Sergei F; Heumann, Klaus G

    2006-01-01

    A method by inductively coupled plasma mass spectrometry (ICP-MS) was developed which allows the measurement of (236)U at concentration ranges down to 3 x 10(-14)g g(-1) and extremely low (236)U/(238)U isotope ratios in soil samples of 10(-7). By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5,000 counts fg(-1) uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH(+)/U(+) down to a level of 10(-6). An abundance sensitivity of 3 x 10(-7) was observed for (236)U/(238)U isotope ratio measurements at mass resolution 4000. The detection limit for (236)U and the lowest detectable (236)U/(238)U isotope ratio were improved by more than two orders of magnitude compared with corresponding values by alpha spectrometry. Determination of uranium in soil samples collected in the vicinity of Chernobyl nuclear power plant (NPP) resulted in that the (236)U/(238)U isotope ratio is a much more sensitive and accurate marker for environmental contamination by spent uranium in comparison to the (235)U/(238)U isotope ratio. The ICP-MS technique allowed for the first time detection of irradiated uranium in soil samples even at distances more than 200 km to the north of Chernobyl NPP (Mogilev region). The concentration of (236)U in the upper 0-10 cm soil layers varied from 2 x 10(-9)g g(-1) within radioactive spots close to the Chernobyl NPP to 3 x 10(-13)g g(-1) on a sampling site located by >200 km from Chernobyl.

  3. atpE gene as a new useful specific molecular target to quantify Mycobacterium in environmental samples

    Science.gov (United States)

    2013-01-01

    Background The environment is the likely source of many pathogenic mycobacterial species but detection of mycobacteria by bacteriological tools is generally difficult and time-consuming. Consequently, several molecular targets based on the sequences of housekeeping genes, non-functional RNA and structural ribosomal RNAs have been proposed for the detection and identification of mycobacteria in clinical or environmental samples. While certain of these targets were proposed as specific for this genus, most are prone to false positive results in complex environmental samples that include related, but distinct, bacterial genera. Nowadays the increased number of sequenced genomes and the availability of software for genomic comparison provide tools to develop novel, mycobacteria-specific targets, and the associated molecular probes and primers. Consequently, we conducted an in silico search for proteins exclusive to Mycobacterium spp. genomes in order to design sensitive and specific molecular targets. Results Among the 3989 predicted proteins from M. tuberculosis H37Rv, only 11 proteins showed 80% to 100% of similarity with Mycobacterium spp. genomes, and less than 50% of similarity with genomes of closely related Corynebacterium, Nocardia and Rhodococcus genera. Based on DNA sequence alignments, we designed primer pairs and a probe that specifically detect the atpE gene of mycobacteria, as verified by quantitative real-time PCR on a collection of mycobacteria and non-mycobacterial species. The real-time PCR method we developed was successfully used to detect mycobacteria in tap water and lake samples. Conclusions The results indicate that this real-time PCR method targeting the atpE gene can serve for highly specific detection and precise quantification of Mycobacterium spp. in environmental samples. PMID:24299240

  4. A sensitive analytical procedure for monitoring acrylamide in environmental water samples by offline SPE-UPLC/MS/MS.

    Science.gov (United States)

    Togola, Anne; Coureau, Charlotte; Guezennec, Anne-Gwenaëlle; Touzé, Solène

    2015-05-01

    The presence of acrylamide in natural systems is of concern from both environmental and health points of view. We developed an accurate and robust analytical procedure (offline solid phase extraction combined with UPLC/MS/MS) with a limit of quantification (20 ng L(-1)) compatible with toxicity threshold values. The optimized (considering the nature of extraction phases, sampling volumes, and solvent of elution) solid phase extraction (SPE) was validated according to ISO Standard ISO/IEC 17025 on groundwater, surface water, and industrial process water samples. Acrylamide is highly polar, which induces a high variability during the SPE step, therefore requiring the use of C(13)-labeled acrylamide as an internal standard to guarantee the accuracy and robustness of the method (uncertainty about 25 % (k = 2) at limit of quantification level). The specificity of the method and the stability of acrylamide were studied for these environmental media, and it was shown that the method is suitable for measuring acrylamide in environmental studies.

  5. Ultra-high sensitive PAH analysis of certified reference materials and environmental samples by GC-APLI-MS.

    Science.gov (United States)

    Große Brinkhaus, Sigrid; Thiäner, Jan B; Achten, Christine

    2017-04-01

    Due to several polycyclic aromatic hydrocarbons (PAHs) being highly carcinogenic and at the same time occurring at very low environmental concentrations up to the microgram per kilogram range, highly sensitive chemical analysis in various matrices is needed. Here, for the first time, a method using gas chromatography (GC) and atmospheric pressure laser ionization-mass spectrometry (APLI-MS), which is much more sensitive compared to common GC-MS, proved to produce reliable (certified reference materials) and comparable (GC-MS) results. PAHs and selected isomers of alkyl-PAHs were targeted, whereby 53 analytes could be quantified individually; for one pair, the sum had to be calculated. In combination with the selective and sensitive (1+1)-REMPI process of the APLI, limits of detection (LODs) between 5 and 50 fg/μL could be obtained. To prove the reliability of this method, four certified reference materials (SRM1649b urban dust, SRM 1941b organics in marine sediment, BCR 535 fresh water harbor sediment, and ERM CC013a contaminated soil from a former gas plant site) were analyzed. The results were in good accordance with the certified values. In addition, analytical results of three different environmental matrices (bituminous coal, suspended particulate matter from river and pine needles) were compared to values obtained with well-established GC-EI-MS. The results show that this method presents an excellent tool ready-to-use for the analysis of environmental samples with very low PAH content or very low sample amount.

  6. Prevalence of Coxiella burnetii in environmental samples collected from cattle farms in Eastern and Central Poland (2011-2012).

    Science.gov (United States)

    Bielawska-Drózd, Agata; Cieślik, Piotr; Mirski, Tomasz; Gaweł, Jerzy; Michalski, Aleksander; Niemcewicz, Marcin; Bartoszcze, Michał; Żakowska, Dorota; Lasocki, Krzysztof; Knap, Józef; Kocik, Janusz

    2014-12-05

    Coxiella burnetii is the etiologic agent of Q fever. It may occur as two different morphological forms, a large cell variant (LCV) and a small cell variant (SCV). The SCV is characterized by unique resistance to physical and chemical factors and may survive in the environment for many months. The objective of this study was to examine environmental samples for the presence of C. burnetii using real-time PCR in areas where Q fever was previously reported and in randomly selected animal farms where Q fever was not reported. The samples were collected in the following provinces in Poland: Lublin, Subcarpathian and Masovian. Monitoring was performed with real-time PCR and serological methods. Of the 727 environmental samples, 33 (4.54%) contained the multi-copy insertion sequence IS1111, which is specific for C. burnetii. Subsequently, the presence of C. burnetii antibodies was determined using serological tests in selected herds in which positive genetic results were obtained. Serological analyses of 169 serum samples using CFT and ELISA were performed on Polish black-and-white Holstein-Friesian cows and one cow imported from Denmark. Using the CFT method, 11 samples were positive for phase I antibodies and six were positive for phase II antibodies. Moreover, in two cases, the presence of antibodies specific for both phase I and phase II antigens of C. burnetii was detected. However, of the 169 examined serum samples, 20 were positive by ELISA test, of which six were also positive by CFT. Additionally, multi spacer typing (MST) of isolated C. burnetii strains was performed. The MST results identified two new genotypes in Poland, ST3 and ST6. The results indicate that continued research regarding spread of this pathogen within a country is necessary. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Shiga Toxin-Producing Serogroup O91 Escherichia coli Strains Isolated from Food and Environmental Samples.

    Science.gov (United States)

    Feng, Peter C H; Delannoy, Sabine; Lacher, David W; Bosilevac, Joseph M; Fach, Patrick; Beutin, Lothar

    2017-09-15

    Shiga toxin-producing Escherichia coli (STEC) strains of the O91:H21 serotype have caused severe infections, including hemolytic-uremic syndrome. Strains of the O91 serogroup have been isolated from food, animals, and the environment worldwide but are not well characterized. We used a microarray and other molecular assays to examine 49 serogroup O91 strains (environmental, food, and clinical strains) for their virulence potential and phylogenetic relationships. Most of the isolates were identified to be strains of the O91:H21 and O91:H14 serotypes, with a few O91:H10 strains and one O91:H9 strain being identified. None of the strains had the eae gene, which codes for the intimin adherence protein, and many did not have some of the genetic markers that are common in other STEC strains. The genetic profiles of the strains within each serotype were similar but differed greatly between strains of different serotypes. The genetic profiles of the O91:H21 strains that we tested were identical or nearly identical to those of the clinical O91:H21 strains that have caused severe diseases. Multilocus sequence typing and clustered regularly interspaced short palindromic repeat analyses showed that the O91:H21 strains clustered within the STEC 1 clonal group but the other O91 serotype strains were phylogenetically diverse. IMPORTANCE This study showed that food and environmental O91:H21 strains have similar genotypic profiles and Shiga toxin subtypes and are phylogenetically related to the O91:H21 strains that have caused hemolytic-uremic syndrome, suggesting that these strains may also have the potential to cause severe illness. Copyright © 2017 American Society for Microbiology.

  8. Fishing in the Water: Effect of Sampled Water Volume on Environmental DNA-Based Detection of Macroinvertebrates.

    Science.gov (United States)

    Mächler, Elvira; Deiner, Kristy; Spahn, Fabienne; Altermatt, Florian

    2016-01-05

    Accurate detection of organisms is crucial for the effective management of threatened and invasive species because false detections directly affect the implementation of management actions. The use of environmental DNA (eDNA) as a species detection tool is in a rapid development stage; however, concerns about accurate detections using eDNA have been raised. We evaluated the effect of sampled water volume (0.25 to 2 L) on the detection rate for three macroinvertebrate species. Additionally, we tested (depending on the sampled water volume) what amount of total extracted DNA should be screened to reduce uncertainty in detections. We found that all three species were detected in all volumes of water. Surprisingly, however, only one species had a positive relationship between an increased sample volume and an increase in the detection rate. We conclude that the optimal sample volume might depend on the species-habitat combination and should be tested for the system where management actions are warranted. Nevertheless, we minimally recommend sampling water volumes of 1 L and screening at least 14 μL of extracted eDNA for each sample to reduce uncertainty in detections when studying macroinvertebrates in rivers and using our molecular workflow.

  9. Determination of total mercury for marine environmental monitoring studies by solid sampling continuum source high resolution atomic absorption spectrometry

    Science.gov (United States)

    Mandjukov, Petko; Orani, Anna Maria; Han, Eunmi; Vassileva, Emilia

    2015-01-01

    The most critical step in almost all commonly used analytical procedures for Hg determination is the sample preparation due to its extreme volatility. One of the possible solutions of this problem is the application of methods for direct analysis of solid samples. The possibilities for solid sampling high resolution continuum source atomic absorption spectrometry (HR CS AAS) determination of total mercury in various marine environmental samples e.g. sediments and biota are object of the present study. The instrumental parameters were optimized in order to obtain reproducible and interference free analytical signal. A calibration technique based on the use of solid standard certified reference materials similar to the nature of the analyzed sample was developed and applied to various CRMs and real samples. This technique allows simple and reliable evaluation of the uncertainty of the result and the metrological characteristics of the method. A validation approach in line with the requirements of ISO 17025 standard and Eurachem guidelines was followed. With this in mind, selectivity, working range (0.06 to 25 ng for biota and 0.025 to 4 ng for sediment samples, expressed as total Hg) linearity (confirmed by Student's t-test), bias (1.6-4.3%), repeatability (4-9%), reproducibility (9-11%), and absolute limit of detection (0.025 ng for sediment, 0.096 ng for marine biota) were systematically assessed using solid CRMs. The relative expanded uncertainty was estimated at 15% for sediment sample and 8.5% for marine biota sample (k = 2). Demonstration of traceability of measurement results is also presented. The potential of the proposed analytical procedure, based on solid sampling HR CS AAS technique was demonstrated by direct analysis of sea sediments form the Caribbean region and various CRMs. Overall, the use of solid sampling HR CS AAS permits obtaining significant advantages for the determination of this complex analyte in marine samples, such as straightforward

  10. Examination of Microbial Proteome Preservation Techniques Applicable to Autonomous Environmental Sample Collection

    Directory of Open Access Journals (Sweden)

    Mak A. Saito

    2011-11-01

    Full Text Available Improvements in temporal and spatial sampling frequency have the potential to open new windows into the understanding of marine microbial dynamics. In recent years, efforts have been made to allow automated samplers to collect microbial biomass for DNA/RNA analyses from moored observatories and autonomous underwater vehicles. Measurements of microbial proteins are also of significant interest given their biogeochemical importance as enzymes that catalyze reactions and transporters that interface with the environment. We examined the influence of five preservatives solutions (SDS-extraction buffer, ethanol, trichloroacetic acid, B-PER, and RNAlater on the proteome integrity of the marine cyanobacterium Synechococcus WH8102 after four weeks of storage at room temperature. Four approaches were used to assess degradation: total protein recovery, band integrity on an SDS-PAGE gel, and number of protein identifications and relative abundances by 1D LC-MS/MS proteomic analyses. Total protein recoveries from the preserved samples were lower than the frozen control due to processing losses, which could be corrected for with internal standardization. The trichloroacetic acid preserved sample showed significant loss of protein band integrity on the SDS-PAGE gel. The RNAlater preserved sample showed the highest number of protein identifications (103% relative to the control; 520 + 31 identifications in RNAlater versus 504 + 4 in the control, equivalent to the frozen control. Relative abundances of individual proteins in the RNAlater treatment were quite similar to that of the frozen control (average ratio of 1.01 + 0.27 for the 50 most abundant proteins, while the SDS-extraction buffer, ethanol, and B-PER all showed significant decreases in both number of identifications and relative abundances of individual proteins. Based on these findings, RNAlater was an effective proteome preservative, although further study is warranted on additional marine microbes.

  11. Within-otolith variability in chemical fingerprints: implications for sampling designs and possible environmental interpretation.

    Science.gov (United States)

    Di Franco, Antonio; Bulleri, Fabio; Pennetta, Antonio; De Benedetto, Giuseppe; Clarke, K Robert; Guidetti, Paolo

    2014-01-01

    Largely used as a natural biological tag in studies of dispersal/connectivity of fish, otolith elemental fingerprinting is usually analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). LA-ICP-MS produces an elemental fingerprint at a discrete time-point in the life of a fish and can generate data on within-otolith variability of that fingerprint. The presence of within-otolith variability has been previously acknowledged but not incorporated into experimental designs on the presumed, but untested, grounds of both its negligibility compared to among-otolith variability and of spatial autocorrelation among multiple ablations within an otolith. Here, using a hierarchical sampling design of spatial variation at multiple scales in otolith chemical fingerprints for two Mediterranean coastal fishes, we explore: 1) whether multiple ablations within an otolith can be used as independent replicates for significance tests among otoliths, and 2) the implications of incorporating within-otolith variability when assessing spatial variability in otolith chemistry at a hierarchy of spatial scales (different fish, from different sites, at different locations on the Apulian Adriatic coast). We find that multiple ablations along the same daily rings do not necessarily exhibit spatial dependency within the otolith and can be used to estimate residual variability in a hierarchical sampling design. Inclusion of within-otolith measurements reveals that individuals at the same site can show significant variability in elemental uptake. Within-otolith variability examined across the spatial hierarchy identifies differences between the two fish species investigated, and this finding leads to discussion of the potential for within-otolith variability to be used as a marker for fish exposure to stressful conditions. We also demonstrate that a 'cost'-optimal allocation of sampling effort should typically include some level of within-otolith replication in the

  12. Estimation of Natural Radioactivity and Radiation Exposure in Environmental Soil Samples of Golestan, Iran

    Directory of Open Access Journals (Sweden)

    Peyman lotfalinezhad

    2017-06-01

    Full Text Available Introduction: Considering the risk of radiation, the measurement of the natural radiation sources seems to be necessary. In this study, the concentrations of the natural radionuclides, namely 226Ra, 232Th, and 40K, were measured in the soil samples taken from different locations of Golestan, Iran. The measurement results can also be used as a baseline to evaluate the impact of non-nuclear activities and the routine releases of nuclear installations. Materials and Methods: A total of 42 soil samples were collected. The samples were sealed for at least three weeks to ensure the secular equilibrium between 226Ra and 232Th and their respective radioactive progenies. The activity concentrations of natural radionuclides in soil samples were measured using a shielded HPGe detector. Results: The average activity concentrations of 226Ra, 232Th, and 40K were 23, 31, and 453 Bq.kg-1, respectively. To assess the radiological hazards, the Ra equivalent activity as well as the external and internal hazard indices were estimated. Radium equivalent varied within the range of 58.4-142.6 Bq.kg-1 with a mean value of 102.4 Bq.kg-1. The estimated mean values of Hex and Hin (0.28 and 0.34, respectively in the area under investigation were lower than unity as desirable. Therefore, it did not pose any health risks to the population of the area. Conclusion: The results of this study were compared with those of other studies carried out in other countries. As the findings of the present study indicated, the health-related risks causing by the naturally accruing radionuclides was very low in the investigated area.

  13. Development of Radioanalytical and Microanalytical Procedures for the Determination of Actinides in Environmental Samples

    Energy Technology Data Exchange (ETDEWEB)

    Macsik, Zsuzsanna [Institute of Nuclear Techniques, Moegyetem rakpart 9, H-1111 Budapest (Hungary); Vajda, Nora [RadAnal Ltd., Bimbo ut 119/a, H-1026 Budapest (Hungary); Bene, Balazs [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Varga, Zsolt [Institute of Isotopes, Konkoly-Thege M. ut 29-33, H-1121 Budapest (Hungary)

    2008-07-01

    A radio-analytical procedure has been developed for the simultaneous determination of actinides in swipe samples by alpha-spectrometry after the separation of the actinides by extraction chromatography. The procedure is based on the complete decomposition of the sample by destruction with microwave digestion or ashing in furnace. Actinides are separated on an extraction chromatographic column filled with TRU resin (product of Eichrom Industries Inc.). Alpha sources prepared from the separated fractions of americium, plutonium, thorium and uranium are counted by alpha spectrometry. Micro-analytical procedure is being developed for the location and identification of individual particles containing fissile material using solid state nuclear track detectors. The parameters of alpha and fission track detection have been optimized and a procedure has been elaborated to locate the particles on the sample by defining the coordinates of the tracks created by the particles on the track detector. Development of a procedure is planned to separate the located particles using micromanipulator and these particles will be examined individually by different micro- and radio-analytical techniques. (authors)

  14. Mercury exposure due to environmental factors and amalgam restorations in a sample of North Carolina children.

    Science.gov (United States)

    Dilley, D C; Bawden, J W

    1999-01-01

    Dental amalgam restorations provide a potential source for mercury (Hg) exposure in children. This study explored the possibility that Hg levels in dentin of exfoliated primary maxillary canines could detect cumulative Hg exposure from amalgam restorations in a sample of North Carolina children. Twenty-seven exfoliated maxillary canines from 3.3 children, without restorations or caries, were assayed for dentin Hg concentration ([Hg]). Urine samples were obtained from 21 subjects and assayed for [Hg] and diet surveys for seafood ingestion were completed for 26 subjects. A surface/month exposure index (SMEI) was compiled from dental records to quantify each child's cumulative exposure to amalgam restorations. Results showed that dentin [Hg] ranged from undetectable levels to 15.7 ppm with a mean of 3.7 ppm. The SMEI scores ranged from 0-638 with a mean of 95. Ten subjects had low SMEI scores of 0-3, nine had scores 4-100, and eight had scores higher than 100. No statistical correlation was found for SMEI scores and dentin [Hg]. Urine Hg levels were found to be negligible and no relationship was found between urine [Hg] and reported ingestion of seafood or SMEI scores. Hg exposure in this sample of children was low and additional exposure from amalgam restorations could not be detected by the methods used in this study.

  15. Sample preparation for determining polychlorinated dibenzo-p-dioxins and dibenzofurans in environmental samples with the use of a modified carbon column

    Energy Technology Data Exchange (ETDEWEB)

    Soifer, V.S.; Soboleva, E.I.; Brodskii, E.S.; Klyuev, N.A. [Severtsov Institute of Developmental Morphology and Animal Ecology, Moscow (Russian Federation)

    1995-03-01

    Presently, the problem of environmental contamination with highly toxic compounds such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) is extremely urgent. These compounds, which accumulate in the fatty tissues of living organisms because of their lipophilicity and outstanding stability to external factors, can be concentrated in the highest links of trophic chains, affect reproduction processes and the immune system, and cause cancer. The necessity for careful monitoring of the PCDD and PCDF content in the environment is arising. In this work, based on the study of dioxin sorption and desorption on various carbon sorbents, the authors suggested a new modification of carbon columns with a minimum sorbent quantity that is sufficient for determining dioxins in actual samples. The elution of PCDDs and PCDFs from a carbon column on heating was first used; this procedure significantly increased the desorption efficiency and made it possible to employ direct-flow elution. The suggested model for the carbon microcolumn significantly simplified the scheme of sample preparation, markedly reduced its duration, and decreased the quantity of sorbent and the volume of solvent for elution and subsequent sorbent regeneration.

  16. Bioaccumulation of metals and biomarkers of environmental stress in Parablennius sanguinolentus (Pallas, 1814) sampled along the Italian coast.

    Science.gov (United States)

    Ferrante, Margherita; Pappalardo, Anna Maria; Ferrito, Venera; Pulvirenti, Valentina; Fruciano, Carmelo; Grasso, Alfina; Sciacca, Salvatore; Tigano, Concetta; Copat, Chiara

    2017-09-15

    Heavy metal pollution is one of the greatest threats to the ecosystems because it degrades the habitat and is potentially toxic to wildlife and human populations. In the last few decades, bioaccumulation studies performed with a multimarker approach have been a valuable tool for the investigation of environmental and animal safety. We perform an analysis of a benthic teleost fish species - Parablennius sanguinolentus - sampled at several Italian coastal sites with different degrees of anthropogenic pressure. Our integrative analysis encompasses bioaccumulation of 10 metals, biomarkers of environmental stress (micronuclei and nuclear abnormalities) and neutral genetic variation (using sequences of the mtDNA control region). We find a clear and significant correlation of metal bioaccumulation with micronuclei and nuclear abnormalities, especially with undisputed genotoxic metals, such as Cd, Cr, Hg and Pb. Furthermore, the molecular genetic analysis revealed a decrease of genetic variability in the populations more subjected to anthropic pressure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Magnetic hydroxyapatite nanoparticles: an efficient adsorbent for the separation and removal of nitrate and nitrite ions from environmental samples.

    Science.gov (United States)

    Ghasemi, Ensieh; Sillanpää, Mika

    2015-01-01

    A novel type of magnetic nanosorbent, hydroxyapatite-coated Fe2O3 nanoparticles was synthesized and used for the adsorption and removal of nitrite and nitrate ions from environmental samples. The properties of synthesized magnetic nanoparticles were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray powder diffraction. After the adsorption process, the separation of γ-Fe2O3@hydroxyapatite nanoparticles from the aqueous solution was simply achieved by applying an external magnetic field. The effects of different variables on the adsorption efficiency were studied simultaneously using an experimental design. The variables of interest were amount of magnetic hydroxyapatite nanoparticles, sample volume, pH, stirring rate, adsorption time, and temperature. The experimental parameters were optimized using a Box-Behnken design and response surface methodology after a Plackett-Burman screening design. Under the optimum conditions, the adsorption efficiencies of magnetic hydroxyapatite nanoparticles adsorbents toward NO3(-) and NO2(-) ions (100 mg/L) were in the range of 93-101%. The results revealed that the magnetic hydroxyapatite nanoparticles adsorbent could be used as a simple, efficient, and cost-effective material for the removal of nitrate and nitrite ions from environmental water and soil samples. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. A simple design for microwave assisted digestion vessel with low reagent consumption suitable for food and environmental samples

    Science.gov (United States)

    Gholami, Mehrdad; Behkami, Shima; Zain, Sharifuddin Md.; Bakirdere, Sezgin

    2016-11-01

    The objective of this work is to prepare a cost-effective, low reagent consumption and high performance polytetrafluoroethylene (PTFE) vessel that is capable to work in domestic microwave for digesting food and environmental samples. The designed vessel has a relatively thicker wall compared to that of commercial vessels. In this design, eight vessels are placed in an acrylonitrile butadiene styrene (ABS) holder to keep them safe and stable. This vessel needs only 2.0 mL of HNO3 and 1.0 mL H2O2 to digest 100 mg of biological sample. The performance of this design is then evaluated with an ICP-MS instrument in the analysis of the several NIST standard reference material of milk 1849a, rice flour 1568b, spinach leave 1570a and Peach Leaves 1547 in a domestic microwave oven with inverter technology. Outstanding agreement to (SRM) values are observed by using the suggested power to time microwave program, which simulates the reflux action occurring in this closed vessel. Taking into account the high cost of commercial microwave vessels and the volume of chemicals needed for various experiments (8-10 mL), this simple vessel is cost effective and suitable for digesting food and environmental samples.

  19. Environmental sampling for avian influenza virus A (H5N1) in live-bird markets, Indonesia.

    Science.gov (United States)

    Indriani, Risa; Samaan, Gina; Gultom, Anita; Loth, Leo; Irianti, Sri; Indryani, Sri; Adjid, Rma; Dharmayanti, Ni Luh Putu Indi; Weaver, John; Mumford, Elizabeth; Lokuge, Kamalini; Kelly, Paul M; Darminto

    2010-12-01

    To identify environmental sites commonly contaminated by avian influenza virus A (H5N1) in live-bird markets in Indonesia, we investigated 83 markets in 3 provinces in Indonesia. At each market, samples were collected from up to 27 poultry-related sites to assess the extent of contamination. Samples were tested by using real-time reverse transcription-PCR and virus isolation. A questionnaire was used to ascertain types of birds in the market, general infrastructure, and work practices. Thirty-nine (47%) markets showed contamination with avian influenza virus in ≥ 1 of the sites sampled. Risk factors were slaughtering birds in the market and being located in West Java province. Protective factors included daily removal of waste and zoning that segregated poultry-related work flow areas. These results can aid in the design of evidence-based programs concerning environmental sanitation, food safety, and surveillance to reduce the risk for avian influenza virus A (H5N1) transmission in live-bird markets.

  20. Environmental monitoring study of linear alkylbenzene sulfonates and insoluble soap in Spanish sewage sludge samples.

    Science.gov (United States)

    Cantarero, Samuel; Zafra-Gómez, Alberto; Ballesteros, Oscar; Navalón, Alberto; Reis, Marco S; Saraiva, Pedro M; Vílchez, José L

    2011-01-01

    In this work we present a monitoring study of linear alkylbenzene sulfonates (LAS) and insoluble soap performed on Spanish sewage sludge samples. This work focuses on finding statistical relations between LAS concentrations and insoluble soap in sewage sludge samples and variables related to wastewater treatment plants such as water hardness, population and treatment type. It is worth to mention that 38 samples, collected from different Spanish regions, were studied. The statistical tool we used was Principal Component Analysis (PC), in order to reduce the number of response variables. The analysis of variance (ANOVA) test and a non-parametric test such as the Kruskal-Wallis test were also studied through the estimation of the p-value (probability of obtaining a test statistic at least as extreme as the one that was actually observed, assuming that the null hypothesis is true) in order to study possible relations between the concentration of both analytes and the rest of variables. We also compared LAS and insoluble soap behaviors. In addition, the results obtained for LAS (mean value) were compared with the limit value proposed by the future Directive entitled "Working Document on Sludge". According to the results, the mean obtained for soap and LAS was 26.49 g kg(-1) and 6.15 g kg(-1) respectively. It is worth noting that LAS mean was significantly higher than the limit value (2.6 g kg(-1)). In addition, LAS and soap concentrations depend largely on water hardness. However, only LAS concentration depends on treatment type.

  1. A single mini-barcode test to screen for Australian mammalian predators from environmental samples.

    Science.gov (United States)

    Modave, Elodie; MacDonald, Anna J; Sarre, Stephen D

    2017-08-01

    Identification of species from trace samples is now possible through the comparison of diagnostic DNA fragments against reference DNA sequence databases. DNA detection of animals from non-invasive samples, such as predator faeces (scats) that contain traces of DNA from their species of origin, has proved to be a valuable tool for the management of elusive wildlife. However, application of this approach can be limited by the availability of appropriate genetic markers. Scat DNA is often degraded, meaning that longer DNA sequences, including standard DNA barcoding markers, are difficult to recover. Instead, targeted short diagnostic markers are required to serve as diagnostic mini-barcodes. The mitochondrial genome is a useful source of such trace DNA markers because it provides good resolution at the species level and occurs in high copy numbers per cell. We developed a mini-barcode based on a short (178 bp) fragment of the conserved 12S ribosomal ribonucleic acid mitochondrial gene sequence, with the goal of discriminating amongst the scats of large mammalian predators of Australia. We tested the sensitivity and specificity of our primers and can accurately detect and discriminate amongst quolls, cats, dogs, foxes, and devils from trace DNA samples. Our approach provides a cost-effective, time-efficient, and non-invasive tool that enables identification of all 8 medium-large mammal predators in Australia, including native and introduced species, using a single test. With modification, this approach is likely to be of broad applicability elsewhere. © The Authors 2017. Published by Oxford University Press.

  2. Determination of plutonium in environmental samples by controlled valence in anion exchange

    DEFF Research Database (Denmark)

    Chen, Q.J.; Aarkrog, A.; Nielsen, S.P.

    1993-01-01

    The title method was successfully used for collecting Pu-239, Pu-249 from 200 litres of seawater by coprecipitation with 16 g FeSO4 . 7H2O under reducing conditions without filtering. The plutonium is leached by concentrated HNO3 + HCI from the coprecipitate and the solid particles. The precipita...... stripped by H20, NaOH, 2N HNO3 and 0.5N HNO3 containing 0.01M NaNO3. The chemical yield of plutonium for a 200 l seawater sample is 60-80%. The resolution of the electroplated thin source is very good....

  3. Within-otolith variability in chemical fingerprints: implications for sampling designs and possible environmental interpretation.

    Directory of Open Access Journals (Sweden)

    Antonio Di Franco

    Full Text Available Largely used as a natural biological tag in studies of dispersal/connectivity of fish, otolith elemental fingerprinting is usually analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS. LA-ICP-MS produces an elemental fingerprint at a discrete time-point in the life of a fish and can generate data on within-otolith variability of that fingerprint. The presence of within-otolith variability has been previously acknowledged but not incorporated into experimental designs on the presumed, but untested, grounds of both its negligibility compared to among-otolith variability and of spatial autocorrelation among multiple ablations within an otolith. Here, using a hierarchical sampling design of spatial variation at multiple scales in otolith chemical fingerprints for two Mediterranean coastal fishes, we explore: 1 whether multiple ablations within an otolith can be used as independent replicates for significance tests among otoliths, and 2 the implications of incorporating within-otolith variability when assessing spatial variability in otolith chemistry at a hierarchy of spatial scales (different fish, from different sites, at different locations on the Apulian Adriatic coast. We find that multiple ablations along the same daily rings do not necessarily exhibit spatial dependency within the otolith and can be used to estimate residual variability in a hierarchical sampling design. Inclusion of within-otolith measurements reveals that individuals at the same site can show significant variability in elemental uptake. Within-otolith variability examined across the spatial hierarchy identifies differences between the two fish species investigated, and this finding leads to discussion of the potential for within-otolith variability to be used as a marker for fish exposure to stressful conditions. We also demonstrate that a 'cost'-optimal allocation of sampling effort should typically include some level of within

  4. Results of stainless steel canister corrosion studies and environmental sample investigations

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Charles R. [Sandia National Laboratories, Albuquerque, NM (United States); Enos, David [Sandia National Laboratories, Albuquerque, NM (United States)

    2014-12-01

    This progress report describes work being done at Sandia National Laboratories (SNL) to assess the localized corrosion performance of container/cask materials used in the interim storage of used nuclear fuel. The work involves both characterization of the potential physical and chemical environment on the surface of the storage canisters and how it might evolve through time, and testing to evaluate performance of the canister materials under anticipated storage conditions. To evaluate the potential environment on the surface of the canisters, SNL is working with the Electric Power Research Institute (EPRI) to collect and analyze dust samples from the surface of in-service SNF storage canisters. In FY 13, SNL analyzed samples from the Calvert Cliffs Independent Spent Fuel Storage Installation (ISFSI); here, results are presented for samples collected from two additional near-marine ISFSI sites, Hope Creek NJ, and Diablo Canyon CA. The Hope Creek site is located on the shores of the Delaware River within the tidal zone; the water is brackish and wave action is normally minor. The Diablo Canyon site is located on a rocky Pacific Ocean shoreline with breaking waves. Two types of samples were collected: SaltSmart™ samples, which leach the soluble salts from a known surface area of the canister, and dry pad samples, which collected a surface salt and dust using a swipe method with a mildly abrasive ScotchBrite™ pad. The dry samples were used to characterize the mineralogy and texture of the soluble and insoluble components in the dust via microanalytical techniques, including mapping X-ray Fluorescence spectroscopy and Scanning Electron Microscopy. For both Hope Creek and Diablo Canyon canisters, dust loadings were much higher on the flat upper surfaces of the canisters than on the vertical sides. Maximum dust sizes collected at both sites were slightly larger than 20 μm, but Phragmites grass seeds ~1 mm in size, were observed on the tops of the Hope Creek canisters

  5. Gold nanoparticles based solid-phase microextraction coatings for determining organochlorine pesticides in aqueous environmental samples.

    Science.gov (United States)

    Gutiérrez-Serpa, Adrián; Rocío-Bautista, Priscilla; Pino, Verónica; Jiménez-Moreno, Francisco; Jiménez-Abizanda, Ana I

    2017-05-01

    The use of solid-phase microextraction coatings based on gold nanoparticles was investigated, focusing the attention on the preparation of nanoparticles with nonclassical reduction agents of HAuCl4 such as gallic acid and H2 O2 , rather than the conventional sodium citrate. All nanoparticles were characterized by diode array spectroscopy, whereas novel nanoparticles prepared with gallic acid and H2 O2 were also characterized by microscopic techniques. Solid-phase microextraction coatings were prepared with a layer-by-layer approach. Gallic acid permitted the preparation of stable nanoparticles with milder experimental conditions (1 min, room temperature) and provided the most uniform coatings (thickness ∼3 μm). Seven organochlorine pesticides were determined in different environmental waters using gas chromatography with electron capture detection. Despite the low thickness of the coatings, limits of detection of the entire method down to 0.13 μg/L were obtained. A comparison with the commercial polyacrylate in terms of the partition coefficients of the analytes to the coatings gave logarithm of the partition coefficient values two times higher with gallic acid than polyacrylate (although the commercial fiber is 28 times thicker). Interfiber relative standard deviation values ranged from 8.67 to 21.3%. Optimum fibers also presented an adequate lifetime (>100 extractions). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Genetic Characterization of Cronobacter sakazakii Recovered from the Environmental Surveillance Samples During a Sporadic Case Investigation of Foodborne Illness.

    Science.gov (United States)

    Sulaiman, Irshad M; Jacobs, Emily; Segars, Katharine; Simpson, Steven; Kerdahi, Khalil

    2016-08-01

    Cronobacter sakazakii is an opportunistic human-pathogenic bacterium known to cause acute meningitis and necrotizing enterocolitis in neonates and immunocompromised individuals. This human-pathogenic microorganism has been isolated from a variety of food and environmental samples, and has been also linked to foodborne outbreaks associated with powdered infant formula (PIF). The U.S. Food and Drug Administration have a policy of zero tolerance of these organisms in PIF. Thus, this agency utilizes the presence of these microorganisms as one of the criteria in implementing regulatory actions and assessing adulteration of food products of public health importance. In this study, we recovered two isolates of Cronobacter from the 91 environmental swab samples during an investigation of sporadic case of foodborne illness following conventional microbiological protocols. The isolated typical colonies were identified using VITEK2 and real-time PCR protocols. The recovered Cronobacter isolates were then characterized for species identification by sequencing the 16S rRNA locus. Further, multilocus sequence typing (MLST) was accomplished characterizing seven known C. sakazakii-specific MLST loci (atpD, fusA, glnS, gltB, gyrB, infB, and pps). Results of this study confirmed all of the recovered Cronobacter isolates from the environmental swab samples to be C. sakazakii. The MLST profile matched with the published profile of the complex 31 of C. sakazakii. Thus, rRNA and 7-loci MLST-based sequencing protocols are robust techniques for rapid detection and differentiation of Cronobacter species, and these molecular diagnostic tools can be used in implementing successful surveillance program and in the control and prevention of foodborne illness.

  7. Determination of Tellurium(IV in Various Environmental Samples with Spectrophotometry

    Directory of Open Access Journals (Sweden)

    P. Reddy Prasad

    2007-01-01

    Full Text Available A rapid, simple and sensitive spectrophotometer method for the determination of traces and ultra traces of tellurium(IV were studied. These method were based on either the oxidation of leuco methylene green (LMG to its blue form of methylene green by tellurium in acidic medium, the formed dye shows an absorption maximum at 650 nm in acetate buffer medium (pH 3.0 to 5.0. Beer’s law were obeyed in the concentration range 0.4-2.5 µg mL-1, having molar absorptivity and Sandal’s sensitivity of 4.9×104 L mol-1 cm-2 , and 0.0026 µg cm-2, respectively. The optimum reaction conditions and other analytical parameters were investigated to enhance the sensitivity of the present method. The tolerance limit of various ions with this method has been studied. The proposed method was applied for the analysis of tellurium in spiked, river, lake, spring, waste water samples, plant materials and soil samples. The results obtained by the proposed method were superior to the reported method. The performances of proposed methods were evaluated in terms of student’s ‘t’-test and variance ratio ‘f’-test which indicates the significance of proposed methods over reported methods.

  8. A new system for the spectrophotometric determination of trace amounts of nitrite in environmental samples

    Directory of Open Access Journals (Sweden)

    Cherian Tom

    2006-01-01

    Full Text Available A selective and rapid spectrophotometric method for the determination of nitrite is presented. It is based on the reaction of nitrite with p-nitroaniline in acid medium to form diazonium ion, which is coupled with ethoxyethylenemaleic ester or ethylcyanoacetate in basic medium to form azo dyes, showing absorption maxima at 439 and 465 nm respectively. The method obeys Beer's law in the concentration range of 0.5-16 µg mL-1 of nitrite with ethoxyethylenemaleic ester and 0.2-18 µg mL-1 of nitrite with ethylcyanoacetate. The molar absorptivity and Sandell's sensitivity of p-nitroaniline-ethoxyethylenemaleic ester and p-nitroaniline-ethylcyanoacetate azo dyes are 5.04 X 10(4 L mol-1cm-1, 0.98 X 10-2 µg cm-2 and 1.21 X 10(4 L mol-1 cm-1, 0.98 X 10-2 µg cm-2 respectively. The optimum reaction conditions and other analytical parameters were evaluated. The method was successfully applied to the determination of nitrite in various water samples and soil samples.

  9. Gene-Based Detection of Microorganisms in Environmental Samples Using PCR

    Science.gov (United States)

    Glass, John I.; Lefkowitz, Elliot J.; Cassell, Gail H.; Wechser, Mark; Taylor, Theresa B.; Albin, Michael; Paszko-Kolva, Christine; Roman, Monsi C.

    1997-01-01

    Contaminating microorganisms pose a serious potential risk to the crew's well being and water system integrity aboard the International Space Station (ISS). We are developing a gene-based microbial monitor that functions by replicating specific segments of DNA as much as 10(exp 12) x. Thus a single molecule of DNA can be replicated to detectable levels, and the kinetics of that molecule's accumulation can be used to determine the original concentration of specific microorganisms in a sample. Referred to as the polymerase chain reaction (PCR), this enzymatic amplification of specific segments of the DNA or RNA from contaminating microbes offers the promise of rapid, sensitive, quantitative detection and identification of bacteria, fungi, viruses, and parasites. We envision a small instrument capable of assaying an ISS water sample for 48 different microbes in a 24 hour period. We will report on both the developments in the chemistry necessary for the PCR assays to detect microbial contaminants in ISS water, and on progress towards the miniaturization and automation of the instrumentation.

  10. Versatile combustion-amalgamation technique for the photometric determination of mercury in fish and environmental samples

    Science.gov (United States)

    Willford, Wayne A.; Hesselberg, Robert J.; Bergman, Harold L.

    1973-01-01

    Total mercury in a variety of substances is determined rapidly and precisely by direct sample combustion, collection of released mercury by amalgamation, and photometric measurement of mercury volatilized from the heated amalgam. Up to 0.2 g fish tissue is heated in a stream of O2 (1.2 L/min) for 3.5 min in 1 tube of a 2-tube induction furnace. The released mercury vapor and combustion products are carried by the stream of O2 through a series of traps (6% NaOH scrubber, water condenser, and Mg(CIO4)2 drying tube) and the mercury is collected in a 10 mm diameter column of 24 gauge gold wire (8 g) cut into 3 mm lengths. The resulting amalgam is heated in the second tube of the induction furnace and the volatilized mercury is measured with a mercury vapor meter equipped with a recorder-integrator. Total analysis time is approximately 8 min/sample. The detection limit is less than 0.002 μg and the system is easily converted for use with other biological materials, water, and sediments.

  11. Power and sample size determination for measures of environmental impact in aquatic systems

    Energy Technology Data Exchange (ETDEWEB)

    Ammann, L.P. [Univ. of Texas, Richardson, TX (United States); Dickson, K.L.; Waller, W.T.; Kennedy, J.H. [Univ. of North Texas, Denton, TX (United States); Mayer, F.L.; Lewis, M. [Environmental Protection Agency, Gulf Breeze, FL (United States)

    1994-12-31

    To effectively monitor the status of various freshwater and estuarine ecological systems, it is necessary to understand the statistical power associated with the measures of ecological health that are appropriate for each system. These power functions can then be used to determine sample sizes that are required to attain targeted change detection likelihoods. A number of different measures have been proposed and are used for such monitoring. these include diversity and evenness indices, richness, and organisms counts. Power functions can be estimated when preliminary or historical data are available for the region and system of interest. Unfortunately, there are a number of problems associated with the computation of power functions and sample sizes for these measures. These problems include the presence of outliers, co-linearity among the variables, and non-normality of count data. The problems, and appropriate methods to compute the power functions, for each of the commonly employed measures of ecological health will be discussed. In addition, the relationship between power and the level of taxonomic classification used to compute the measures of diversity, evenness, richness, and organism counts will be discussed. Methods for computation of the power functions will be illustrated using data sets from previous EPA studies.

  12. Measurement of uranium and its isotopes at trace levels in environmental samples using mass spectrometry

    Science.gov (United States)

    Sahoo, S. K.

    2009-06-01

    Actinides have widely entered the environment as a result of nuclear accidents and atmospheric weapon testing. These radionuclides, especially uranium, are outstanding radioactive pollutants, due to their high radiotoxicity and long half-lives. In addition to this, since depleted uranium (DU) has been used in the Balkan conflict in 1999, there has been a concern about the possible consequences of its use for the people and environment. Therefore, accurate, precise and simple determination methods are necessary in order to evaluate the human dose and the concentration and effects of these nuclides in the environment. The principal isotopes of uranium e.g. 235U and 238U are of primordial origin and 234U present in radioactive equilibrium with 238U. 236U occurs in nature at ultra trace concentrations with a 236U: 238U atom ratio of 10-14. Concentrations of uranium in soil samples were determined using inductively coupled plasma mass spectrometry (ICP-MS) and isotope ratios of uranium were measured using a thermal ionisation mass spectrometer. Radioactive dis-equilibrium of 234/238U, depletion of 235/238U and significant evidence of 236U/238U were noticed in soil samples.

  13. Determination of actinide elements in environmental samples by ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Truscott, J.B

    2000-11-01

    Methods for the determination of the actinide elements in water, biological, soil and sediment samples have been developed using on-line solid phase extraction and high performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS). Initial applications utilised a commercially available resin, namely TRU-Spec resin, for efficient removal of the matrix prior to elution of uranium and thorium analytes. Comparative analyses of reference materials and natural water samples from Plymouth and Dartmoor demonstrated significant improvement in precision and speed of analysis by using TRU-Spec coupled to ICP-MS compared with alpha spectrometry. Further applications of the TRU-Spec resin for the determination of the transuranic actinide elements neptunium, plutonium and americium, resulted in the successful determination of {sup 239}Pu and {sup 217}Np in biological reference materials. Detection limits were 700, 850, and 600 attograms (ag) for {sup 237}Np, {sup 233}Pu, and {sup 241}Am, respectively, for a 0.5 mI sample injection, and better than 200 ag g{sup -1} with 50 ml pre-concentration when sector field (SF) ICP-MS was used. A method for the selective sequential elution of uranium and plutonium was also developed to facilitate the determination of {sup 239}Pu without interference due to the {sup 238}U{sup 1}H{sup +} polyatomic ion, caused by high concentrations of {sup 238}U in sediment samples. Investigations were performed into the use of a polymeric substrate, which was dynamically coated with chelating dyes such as xylenol orange and 4-(2-pyridylazo) resorcinol, and a silica substrate coated with permanently bonded iminodiacetic acid. The latter was used for the successful determination of uranium and thorium in certified reference material waters. However, the column was found to have a high affinity for iron, making it unsuitable for the determination of the actinides in soil and sediment samples. Subsequently, a

  14. An intercomparison on radionuclides in environmental samples, Baltic-Danish co-operation project on radiation protection 2001-2003

    DEFF Research Database (Denmark)

    Nielsen, S.P.

    2004-01-01

    , 241Am, 226Ra, 232Th and 40K. The evaluation of analytical performance was based on comparison with median values, a 10% target standard deviation and statistical tests at the 99% level. For 137Cs the resultsfrom 10 out of 16 laboratories passed the evaluation tests. For 90Sr the results from 5 out...... laboratories passed the evaluation tests. The results indicate that for several of the laboratories there isroom to improve the analytical quality on radionuclides in environmental samples to match an uncertainty corresponding to a relative standard deviation of 10%....

  15. Arsenic speciation by hydride generation-quartz furnace atomic absorption spectrometry. Optimization of analytical parameters and application to environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Molenat, N.; Astruc, A.; Holeman, M.; Pinel, R. [Laboratoire de Chimie Analytique Bioinorganique et Environnement, Dept. de Chimie, Faculte des Sciences et Techniques, 64 - Pau (France); Maury, G. [Montpellier-2 Univ., 34 (France). Dept. de Chimie Organique Fine

    1999-11-01

    Analytical parameters of hydride generation, trapping, gas chromatography and atomic absorption spectrometry detection in a quartz cell furnace (HG/GC/QFAAS) device have been optimized in order to develop an efficient and sensitive method for arsenic compounds speciation. Good performances were obtained with absolute detection limits in the range of 0.1 - 0.5 ng for arsenite, arsenate, mono-methyl-arsonic acid (MMAA), dimethyl-arsinic acid (DMAA) and trimethyl-arsine oxide (TMAO). A pH selective reduction for inorganic arsenic speciation was successfully reported. Application to the accurate determination of arsenic compounds in different environmental samples was performed. (authors)

  16. Pro NET Best Practices

    CERN Document Server

    Ritchie, Stephen D

    2011-01-01

    Pro .NET Best Practices is a practical reference to the best practices that you can apply to your .NET projects today. You will learn standards, techniques, and conventions that are sharply focused, realistic and helpful for achieving results, steering clear of unproven, idealistic, and impractical recommendations. Pro .NET Best Practices covers a broad range of practices and principles that development experts agree are the right ways to develop software, which includes continuous integration, automated testing, automated deployment, and code analysis. Whether the solution is from a free and

  17. Getting to Net Zero

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-01

    The technology necessary to build net zero energy buildings (NZEBs) is ready and available today, however, building to net zero energy performance levels can be challenging. Energy efficiency measures, onsite energy generation resources, load matching and grid interaction, climatic factors, and local policies vary from location to location and require unique methods of constructing NZEBs. It is recommended that Components start looking into how to construct and operate NZEBs now as there is a learning curve to net zero construction and FY 2020 is just around the corner.

  18. Instant Lucene.NET

    CERN Document Server

    Heydt, Michael

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. A step-by-step guide that helps you to index, search, and retrieve unstructured data with the help of Lucene.NET.Instant Lucene.NET How-to is essential for developers new to Lucene and Lucene.NET who are looking to get an immediate foundational understanding of how to use the library in their application. It's assumed you have programming experience in C# already, but not that you have experience with search techniques such as information retrieval theory (although there will be a l

  19. Ionic liquid for high temperature headspace liquid-phase microextraction of chlorinated anilines in environmental water samples.

    Science.gov (United States)

    Peng, Jin-feng; Liu, Jing-fu; Jiang, Gui-bin; Tai, Chao; Huang, Min-jia

    2005-04-22

    Based on the non-volatility of room temperature ionic liquids (IL), 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MIM][PF6]) IL was employed as an advantageous extraction solvent for high temperature headspace liquid-phase microextraction (LPME) of chloroanilines in environmental water samples. At high temperature of 90 degrees C, 4-chloroaniline, 2-chloroaniline, 3,4-dichloroaniline, and 2,4-dichloroaniline were extracted into a 10 microl drop of [C4MIM][PF6] suspended on the needle of a high-performance liquid chromatography (HPLC) microsyringe held at the headspace of the samples. Then, the IL was injected directly into the HPLC system for determination. Parameters related to LPME were optimized, and high selectivity and low detection limits of the four chlorinated anilines were obtained because the extraction was performed at high temperature in headspace mode and the very high affinity between IL and chlorinated anilines. The proposed procedure was applied for the analysis of the real samples including tap water, river water and wastewater samples from a petrochemical plant and a printworks, and only 3,4-dichloroaniline was detected in the printworks wastewater at 88.2 microg l(-1) level. The recoveries for the four chlorinated anilines in the four samples were all in the range of 81.9-99.6% at 25 microg l(-1) spiked level.

  20. Titanium determination by multisyringe flow injection analysis system and a liquid waveguide capillary cell in solid and liquid environmental samples.

    Science.gov (United States)

    Sánchez-Quiles, David; Tovar-Sánchez, Antonio; Horstkotte, Burkhard

    2013-11-15

    A multisyringe flow injection analysis system using a liquid waveguide capillary cell (MSFIA-LWCC) has been used for the spectrophotometric determination of titanium (Ti) in marine environmental samples. Samples were previous digested using potassium peroxodisulfate (K2S2O8). The method showed to be linear over a range up to 1 μM with a detection limit of 9.2 nM. The analysis consumes little reagent (250 μL) and sample (600 μL). It had an adequate accuracy with high repeatability (RSD of 1.8%) for all marine samples. The proposed method was used to evaluate the concentration of Ti in natural samples collected in the coastal area of the Majorca Island (Western Mediterranean Sea). We report average concentrations of Ti in coastal surface microlayer of 510.7 ± 267.2 nM, in surface sediments of 2.72 ± 1.84 μmol/g, and in rhizomes and leaves of Posidonia oceanica of 310 ± 295 nmol/g and 157 ± 132 nmol/g, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Precise determination of HPGe detector efficiency for gamma spectrometry measurements of environmental samples with variable geometry and density

    Directory of Open Access Journals (Sweden)

    Barrera Manuel

    2017-03-01

    Full Text Available A methodology to determine the full energy peak efficiency (FEPE for precise gamma spectrometry measurements of environmental samples with high-purity germanium (HPGe detector, valid when this efficiency depends on the energy of the radiation E, the height of the cylindrical sample H, and its density ρ, is introduced. The methodology consists of an initial calibration as a function of E and H and the application of a self-attenuation factor, depending on the density of the sample ρ, in order to correct for the different attenuation of the generic sample in relation to the measured standard. The obtained efficiency can be used in the whole range of interest studied, E = 120–2000 keV, H = 1–5 cm, and ρ = 0.8–1.7 g/cm3, being its uncertainty below 5%. The efficiency has been checked by the measurement of standards, resulting in a good agreement between experimental and expected activities. The described methodology can be extended to similar situations when samples show geometric and compaction differences.

  2. Bait type influences on catch and bycatch in tandem hoop nets set in reservoirs

    Science.gov (United States)

    Long, James M.; Stewart, David R.; Shiflet, Jeremy; Balsman, Dane; Shoup, Daniel E.

    2017-01-01

    Tandem hoop nets have become the primary gear for sampling channel catfish Ictalurus punctatus, but suffer from high incidences of bycatch, particularly aquatic turtles that usually drown as a result. We sought to determine if bait type, ZOTE© soap and ground cheese logs, would influence catch of channel catfish (CPUE and mean TL) and bycatch of fishes and aquatic turtles. We sampled with tandem hoop nets in 13 Kentucky reservoirs (5–73 ha) using a crossover design and two sampling events. We found no difference in channel catfish catch rates between bait types, but mean sizes of fish caught using ZOTE© soap were approximately 24 mm longer compared to cheese. Fish bycatch was similar between bait types, but tandem hoop nets baited with ZOTE© soap caught up to 61% fewer turtles and mortality of turtles that were captured was up to 12% lower than those baited with cheese. Depth of net set, water temperature, and Secchi depth were environmental factors measured that affected catch and bycatch, but varied among species. Using ZOTE© soap as bait in tandem hoop nets appears to be a fairly simple and straightforward method for maintaining high catch rates of channel catfish while minimizing turtle mortality.

  3. An in vitro model for screening estrogen activity of environmental samples after metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Chahbane, N.; Schramm, K.W. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Oekologische Chemie; Kettrup, A. [Technische Univ. Muenchen, Freising (Germany). Lehrstuhl fuer Oekologische Chemie

    2004-09-15

    For a few years, yeast estrogen assay (YES) was accepted as a reliable and economic model for screening of environmental estrogens. Though the chemicals directly act with estrogen receptor (ER) can be filtered out by this model, there are still chemicals act with ER only after metabolism and some chemicals eliminate their estrogen activities after metabolism. That is to say, their metabolites exert or have stronger estrogen activities than themselves, which can be called bio-activation. In this case, for the lack of the metabolism enzyme system as human and other animals, only the assay with recombinant yeast cells is insufficient. So, it is necessary to combine the YES with metabolism procedure to evaluate the estrogen activities of these chemicals. The most common method used currently for in vitro metabolic activation in mutagenicity testing and also be applied to the estrogen screening field is S-9 mixture. Also, there is an attempt to develop a chemical model for cytochrome P450 as a bio-mimetic metabolic activation system. All these methods can be used as in vitro models for metabolism. Compare with these models, using whole H4II E cells for metabolism is an alternative and with superiorities. It has the excellence of short experiment period as all other in vitro models, but is much more close to the real surroundings as in vivo. Furthermore, the activity of 7-ethoxyresorufin-O-deethylase (EROD) can be easily measured during the whole incubation period for us to discuss the metabolic activities in a quantitative foundation, not only in qualitative. Methoxychlor is one of the chemicals with bio-activation ability. When directly used in the YES, it shows weak estrogen activity. But a main metabolite of methoxychlor, 2,2-bis (p-hydroxyphenyl) - 1,1,1-trichloroethane (HPTE) is a known estrogen mimic. For the long time using methoxychlor as a pesticide and its clear background, it is an ideal chemical to establish this in vitro system.

  4. Extraction chromatographic separation of Sr, Pu and Am in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Sidhu, Rajdeep

    2004-04-01

    An accurate determination of radionuclides from various sources in the environment is essential for assessment of the potential hazards and suitable countermeasures both in case of an authorised release, accidents and routine surveillance. Due to the short range of alpha and beta radiation, the accurate determination of pure alpha and beta emitters must always include radiochemical separations to separate the analytes from the matrix and from other interfering stable and radioactive nuclides. Hence, the procedures used for their determination are usually tedious and involve several preconcentration and separation steps. This work deals with the determination of {sup 90}Sr, {sup 241}Am, {sup 238}Pu, {sup 239,240}Pu and {sup 244}Cm, whic some of the most important artificial radionuclides. Due to either absence or low yield of gamma radiation, a secure determination of low concentrations of all these nuclides requires a dedicated chemistry. Selective extraction chromatographic resins (TRU- and Sr-Resin) have been utilised to develop new procedures for the analyses of Pu, Am and Cm isotopes in seawater and both these and {sup 90}Sr in soil, sediment, urine and low-level liquid radioactive effluents. The proposed method for the analyses of Pu and Am in seawater offers a quick and secure mode for the determination of these radionuclides in marine waters. Combined pre-concentration of actinides and strontium (oxalate or phosphate precipitation) followed by dual column separation on TRU- and Sr-Resin significantly reduces the through put time and costs compared to traditional ion exchange and precipitation methods. The greatest gain in productivity and environmental friendliness is achieved in Sr separations using Sr-Resin instead of precipitations involving fuming nitric acid and oxalate, hydroxide, chromate and carbonate precipitations. (author)

  5. Detection of a diverse marine fish fauna using environmental DNA from seawater samples

    DEFF Research Database (Denmark)

    Thomsen, Philip Francis; Kielgast, Jos; Iversen, Lars Lønsmann

    2012-01-01

    eDNA from 15 different fish species, including both important consumption species, as well as species rarely or never recorded by conventional monitoring. We also detect eDNA from a rare vagrant species in the area; European pilchard (Sardina pilchardus). Additionally, we detect four bird species......Marine ecosystems worldwide are under threat with many fish species and populations suffering from human over-exploitation. This is greatly impacting global biodiversity, economy and human health. Intriguingly, marine fish are largely surveyed using selective and invasive methods, which are mostly...... for marine fish biodiversity. This eDNA approach has recently been used successfully in freshwater environments, but never in marine settings. We isolate eDNA from 1/2-litre seawater samples collected in a temperate marine ecosystem in Denmark. Using next-generation DNA sequencing of PCR amplicons, we obtain...

  6. Well installation and ground-water sampling plan for 1100 Area environmental monitoring wells

    Energy Technology Data Exchange (ETDEWEB)

    Bryce, R.W.

    1989-05-01

    This report outlines a plan for the installation and sampling of five wells between inactive waste sites in the 1100 Area of the Hanford Site and Richland City water supply wells. No contamination has been detected in water pumped from the water supply wells to date. The five wells are being installed to provide for early detection of contaminants and to provide data that may be used to make decisions concerning the management of the North Richland Well Field. This plan describes the existing waste disposal facilities and water supply wells, hydrogeology of the area, well completion specifics, and the data to be gathered from the five new wells. 26 refs., 8 figs., 4 tabs.

  7. An environmental sample chamber for reliable scanning transmission x-ray microscopy measurements under water vapor

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Stephen T.; Nigge, P.; Prakash, Shruti; Laskin, Alexander; Wang, Bingbing; Tyliszczak, Tolek; Leone, Stephen R.; Gilles, Mary K.

    2013-08-01

    We have designed, fabricated, and tested a compact gas-phase reactor for performing in situ soft x-ray scanning transmission x-ray microscopy (STXM) measurements. The reactor accommodates many gas atmospheres, including reactive or corrosive gasses, but was designed specically to address the needs of measurements under water vapor. An on-board sensor measures the relative humidity and temperature inside the reactor, minimizing uncertainties associated with measuring these quantities outside the instrument. The reactor mounts directly to the existing sample holder used in the majority of STXM instruments around the world and installs with minimal instrument reconguration. Using the reactor contributes over 85% less additional absorption compared to lling the STXM chamber with process gas, and results in much more stable imaging conditions. The reactor is in use at the STXM instruments at beamlines 11.0.2 and 5.3.2.2 at the Advanced Light Source.

  8. DNA typing of ancient parasite eggs from environmental samples identifies human and animal worm infections in viking-age settlement

    DEFF Research Database (Denmark)

    Søe, Martin Jensen; Nejsum, Peter; Fredensborg, Brian Lund

    2015-01-01

    Ancient parasite eggs were recovered from environmental samples collected at a Viking-age settlement in Viborg, Denmark, dated 1018-1030 A.D. Morphological examination identified Ascaris sp., Trichuris sp., and Fasciola sp. eggs, but size and shape did not allow species identification. By carefully...... the Ascaris sp. 18S rRNA gene in recent isolates from humans and pigs of global distribution and show that this is not a suited marker for species-specific identification. Finally, we discuss ancient parasitism in Denmark and the implementation of aDNA analysis methods in paleoparasitological studies. We...... argue that when employing species-specific identification, soil samples offer excellent opportunities for studies of human parasite infections and of human and animal interactions of the past....

  9. Determination of {sup 135}Cs and {sup 137}Cs in environmental samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Russell, B.C., E-mail: ben.russell@npl.co.uk [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom); National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW (United Kingdom); Croudace, Ian W.; Warwick, Phil E. [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom)

    2015-08-26

    Radionuclides of caesium are environmentally important since they are formed as significant high yield fission products ({sup 135}Cs and {sup 137}Cs) and activation products ({sup 134}Cs and {sup 136}Cs) during nuclear fission. They originate from a range of nuclear activities such as weapons testing, nuclear reprocessing and nuclear fuel cycle discharges and nuclear accidents. Whilst {sup 137}Cs, {sup 134}Cs and {sup 136}Cs are routinely measurable at high sensitivity by gamma spectrometry, routine detection of long-lived {sup 135}Cs by radiometric methods is challenging. This measurement is, however, important given its significance in long-term nuclear waste storage and disposal. Furthermore, the {sup 135}Cs/{sup 137}Cs ratio varies with reactor, weapon and fuel type, and accurate measurement of this ratio can therefore be used as a forensic tool in identifying the source(s) of nuclear contamination. The shorter-lived activation products {sup 134}Cs and {sup 136}Cs have a limited application but provide useful early information on fuel irradiation history and have importance in health physics. Detection of {sup 135}Cs (and {sup 137}Cs) is achievable by mass spectrometric techniques; most commonly inductively coupled plasma mass spectrometry (ICP-MS), as well as thermal ionisation (TIMS), accelerator (AMS) and resonance ionisation (RIMS) techniques. The critical issues affecting the accuracy and detection limits achievable by this technique are effective removal of barium to eliminate isobaric interferences arising from {sup 135}Ba and {sup 137}Ba, and elimination of peak tailing of stable {sup 133}Cs on {sup 135}Cs. Isobaric interferences can be removed by chemical separation, most commonly ion exchange chromatography, and/or instrumental separation using an ICP-MS equipped with a reaction cell. The removal of the peak tailing interference is dependent on the instrument used for final measurement. This review summarizes and compares the analytical procedures

  10. Experimental setup for the determination of exchangeable hydrogen in environmental samples using deuterium and tritium

    Energy Technology Data Exchange (ETDEWEB)

    Pastor, L.; Siclet, F. [EDF R et D (France); Peron, O.; Gegout, C.; Montavon, G.; Landesman, C. [Laboratoire SUBATECH, IN2P3/CNRS, EMN, Universite de Nantes (France); Fourre, E.; Jean-Baptiste, P. [LSCE, UMR 8112 CEA-CNRS-UVSQ/IPSL (France)

    2014-07-01

    Tritium ({sup 3}H or T) is a radioactive isotope of the element hydrogen with a half-life of 12.32 yrs. It is naturally produced in the upper atmosphere, but also by the nuclear industry. It is used in many fields like medical research and watch making. It is thus released in the environment on gaseous and liquid form by these facilities and is currently the major released radionuclide in liquid effluent from French nuclear power plants (in HTO form). Current studies dealing with the fate and behavior of tritium in the environment focus mainly on its organic form, i.e. the organically bound tritium (OBT). It is indeed more resilient in the environment than the tritiated water (HTO) as it is part of the organic matter cycle. There is nevertheless a distinction to be made between the exchangeable and the non-exchangeable fraction of OBT. When hydrogen is linked to nitrogen, sulfur or oxygen, it is considered to be exchangeable with the H contained in the surrounding solution or in the atmospheric water phase. Thus, its residence time within the molecule will be reduced and closely linked to the surrounding parameters. When hydrogen is linked to carbon, it is assumed that the link is more stable and thus the residence time in the molecule will be enhanced. It is thus important to know the fraction of exchangeable OBT when addressing the residence time of tritium in the environment. The present study aims at assessing this fraction in different environmental matrixes using deuterium and/or tritium. Compared to several others studies on exchangeable hydrogen where experiments were conducted at high temperature and/or high pressure, this study follows a different approach with experiments conducted at ambient temperature and atmospheric pressure (natural conditions) with a controlled hygrometric value within the system. The system itself consists in a glove box modified to fulfill the requirements for an efficient control on the experimental parameters (temperature

  11. Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Bourrelle, Julien S.; Musall, Eike

    2010-01-01

    and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...... parameters used in the calculations are discussed and the various renewable supply options considered in the methodologies are summarised graphically. Thus, the paper helps to understand different existing approaches to calculate energy balance in Net ZEBs, highlights the importance of variables selection...

  12. PhysioNet

    Data.gov (United States)

    U.S. Department of Health & Human Services — The PhysioNet Resource is intended to stimulate current research and new investigations in the study of complex biomedical and physiologic signals. It offers free...

  13. NetSig

    DEFF Research Database (Denmark)

    Horn, Heiko; Lawrence, Michael S; Chouinard, Candace R

    2018-01-01

    Methods that integrate molecular network information and tumor genome data could complement gene-based statistical tests to identify likely new cancer genes; but such approaches are challenging to validate at scale, and their predictive value remains unclear. We developed a robust statistic (Net......Sig) that integrates protein interaction networks with data from 4,742 tumor exomes. NetSig can accurately classify known driver genes in 60% of tested tumor types and predicts 62 new driver candidates. Using a quantitative experimental framework to determine in vivo tumorigenic potential in mice, we found that Net......Sig candidates induce tumors at rates that are comparable to those of known oncogenes and are ten-fold higher than those of random genes. By reanalyzing nine tumor-inducing NetSig candidates in 242 patients with oncogene-negative lung adenocarcinomas, we find that two (AKT2 and TFDP2) are significantly amplified...

  14. Improved detection of multiple environmental antibiotics through an optimized sample extraction strategy in liquid chromatography-mass spectrometry analysis.

    Science.gov (United States)

    Yi, Xinzhu; Bayen, Stéphane; Kelly, Barry C; Li, Xu; Zhou, Zhi

    2015-12-01

    A solid-phase extraction/liquid chromatography/electrospray ionization/multi-stage mass spectrometry (SPE-LC-ESI-MS/MS) method was optimized in this study for sensitive and simultaneous detection of multiple antibiotics in urban surface waters and soils. Among the seven classes of tested antibiotics, extraction efficiencies of macrolides, lincosamide, chloramphenicol, and polyether antibiotics were significantly improved under optimized sample extraction pH. Instead of only using acidic extraction in many existing studies, the results indicated that antibiotics with low pK a values (antibiotics with high pK a values (>7) were extracted more efficiently under neutral conditions. The effects of pH were more obvious on polar compounds than those on non-polar compounds. Optimization of extraction pH resulted in significantly improved sample recovery and better detection limits. Compared with reported values in the literature, the average reduction of minimal detection limits obtained in this study was 87.6% in surface waters (0.06-2.28 ng/L) and 67.1% in soils (0.01-18.16 ng/g dry wt). This method was subsequently applied to detect antibiotics in environmental samples in a heavily populated urban city, and macrolides, sulfonamides, and lincomycin were frequently detected. Antibiotics with highest detected concentrations were sulfamethazine (82.5 ng/L) in surface waters and erythromycin (6.6 ng/g dry wt) in soils. The optimized sample extraction strategy can be used to improve the detection of a variety of antibiotics in environmental surface waters and soils.

  15. Methodologies for measurement of transuranic elements in environmental samples and migration behavior of transuranic elements in paddy fields

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Masayoshi; Ueno, Kaori [Kanazawa Univ., Tatsunokuchi, Ishikawa (Japan). Low Level Radioactivity Lab.; Amano, Hikaru

    1996-02-01

    Methodologies for the measurement of transuranic elements in environmental samples and migration behavior of transuranic elements in paddy fields are reviewed in this report. Long lived transuranic elements in our environment are quite important, because their effect to human is prolonged. Migration analysis of long lived transuranic elements in paddy fields is also quite important, because rice is our main dishes. For the methodologies about the measurement of transuranic elements in environmental samples, traditional chemical separation and purification plus alpha-ray spectrometric methods are reviewed with mass spectrometric method. For the estimation of migration behavior of transuranic elements in paddy fields, experimental results from 1957y to 1989y in Japan are reviewed. Important findings are as follows. (1) Detection limit of transuranic elements for traditional chemical separation and purification plus alpha-ray spectrometric methods is about 0.2mBq/sample(10,000min counting). On contrast, detection limit of transuranic elements for mass spectrometric methods using High Resolution ICP-MS is 0.02mBq/sample for {sup 237}Np. (2) Integrated deposits of {sup 239,240}Pu and {sup 137}Cs in paddy field soils are 2-3 times higher in Pacific ocean side area than Japan sea side area in Japan. (3) Apparent residence time of {sup 237}Np in paddy field soils was estimated to be in the range of 50-70 years, which is shorter than those of {sup 239,240}Pu and {sup 137}Cs(100-140 years). (author) 54 refs.

  16. Validation of the ANSR Salmonella method for detection of Salmonella spp. in selected foods and environmental samples.

    Science.gov (United States)

    Mozola, Mark; Norton, Paul; Alles, Susan; Gray, R Lucas; Tolan, Jerry; Caballero, Oscar; Pinkava, Lisa; Hosking, Edan; Luplow, Karen; Rice, Jennifer

    2013-01-01

    ANSR Salmonella is a new molecular diagnostic assay for detection of Salmonella spp. in foods and environmental samples. The test is based on the nicking enzyme amplification reaction (NEAR) isothermal nucleic acid amplification technology. The assay platform features simple instrumentation, minimal labor, and, following a single-step 10-24 h enrichment (depending on sample type), an extremely short assay time of 30 min, including sample preparation. Detection is real-time using fluorescent molecular beacon probes. Inclusivity testing was performed using a panel of 113 strains of S. enterica and S. bongori, representing 109 serovars and all genetic subgroups. With the single exception of the rare serovar S. Weslaco, all serovars and genetic subgroups were detected. Exclusivity testing of 38 non-salmonellae, mostly Enterobacteriaceae, yielded no evidence of cross-reactivity. In comparative testing of chicken carcass rinse, raw ground turkey, raw ground beef, hot dogs, and oat cereal, there were no statistically significant differences in the number of positive results obtained with the ANSR and the U.S. Department of Agriculture-Food Safety and Inspection Service or U.S. Food and Drug Administration/Bacteriological Analytical Manual reference culture methods. In testing of swab or sponge samples from five different environmental surfaces, four trials showed no statistically significant differences in the number of positive results by the ANSR and the U.S. Food and Drug Administration/ Bacteriological Analytical Manual reference methods; in the trial with stainless steel surface, there were significantly more positive results by the ANSR method. Ruggedness experiments showed a high degree of assay robustness when deviations in reagent volumes and incubation times were introduced.

  17. Planning long lasting insecticide treated net campaigns: should households' existing nets be taken into account?

    Science.gov (United States)

    Yukich, Joshua; Bennett, Adam; Keating, Joseph; Yukich, Rudy K; Lynch, Matt; Eisele, Thomas P; Kolaczinski, Kate

    2013-06-14

    Mass distribution of long-lasting insecticide treated bed nets (LLINs) has led to large increases in LLIN coverage in many African countries. As LLIN ownership levels increase, planners of future mass distributions face the challenge of deciding whether to ignore the nets already owned by households or to take these into account and attempt to target individuals or households without nets. Taking existing nets into account would reduce commodity costs but require more sophisticated, and potentially more costly, distribution procedures. The decision may also have implications for the average age of nets in use and therefore on the maintenance of universal LLIN coverage over time. A stochastic simulation model based on the NetCALC algorithm was used to determine the scenarios under which it would be cost saving to take existing nets into account, and the potential effects of doing so on the age profile of LLINs owned. The model accounted for variability in timing of distributions, concomitant use of continuous distribution systems, population growth, sampling error in pre-campaign coverage surveys, variable net 'decay' parameters and other factors including the feasibility and accuracy of identifying existing nets in the field. Results indicate that (i) where pre-campaign coverage is around 40% (of households owning at least 1 LLIN), accounting for existing nets in the campaign will have little effect on the mean age of the net population and (ii) even at pre-campaign coverage levels above 40%, an approach that reduces LLIN distribution requirements by taking existing nets into account may have only a small chance of being cost-saving overall, depending largely on the feasibility of identifying nets in the field. Based on existing literature the epidemiological implications of such a strategy is likely to vary by transmission setting, and the risks of leaving older nets in the field when accounting for existing nets must be considered. Where pre-campaign coverage

  18. Planning long lasting insecticide treated net campaigns: should households’ existing nets be taken into account?

    Science.gov (United States)

    2013-01-01

    Background Mass distribution of long-lasting insecticide treated bed nets (LLINs) has led to large increases in LLIN coverage in many African countries. As LLIN ownership levels increase, planners of future mass distributions face the challenge of deciding whether to ignore the nets already owned by households or to take these into account and attempt to target individuals or households without nets. Taking existing nets into account would reduce commodity costs but require more sophisticated, and potentially more costly, distribution procedures. The decision may also have implications for the average age of nets in use and therefore on the maintenance of universal LLIN coverage over time. Methods A stochastic simulation model based on the NetCALC algorithm was used to determine the scenarios under which it would be cost saving to take existing nets into account, and the potential effects of doing so on the age profile of LLINs owned. The model accounted for variability in timing of distributions, concomitant use of continuous distribution systems, population growth, sampling error in pre-campaign coverage surveys, variable net ‘decay’ parameters and other factors including the feasibility and accuracy of identifying existing nets in the field. Results Results indicate that (i) where pre-campaign coverage is around 40% (of households owning at least 1 LLIN), accounting for existing nets in the campaign will have little effect on the mean age of the net population and (ii) even at pre-campaign coverage levels above 40%, an approach that reduces LLIN distribution requirements by taking existing nets into account may have only a small chance of being cost-saving overall, depending largely on the feasibility of identifying nets in the field. Based on existing literature the epidemiological implications of such a strategy is likely to vary by transmission setting, and the risks of leaving older nets in the field when accounting for existing nets must be considered

  19. TideNet

    Science.gov (United States)

    2015-10-30

    query tide data sources in a desired geographic region of USA and its territories (Figure 1). Users can select a tide data source through the Google Map ...select data sources according to the desired geographic region. It uses the Google Map interface to display data from different sources. Recent...Coastal Inlets Research Program TideNet The TideNet is a web-based Graphical User Interface (GUI) that provides users with GIS mapping tools to

  20. Building Neural Net Software

    OpenAIRE

    Neto, João Pedro; Costa, José Félix

    1999-01-01

    In a recent paper [Neto et al. 97] we showed that programming languages can be translated on recurrent (analog, rational weighted) neural nets. The goal was not efficiency but simplicity. Indeed we used a number-theoretic approach to machine programming, where (integer) numbers were coded in a unary fashion, introducing a exponential slow down in the computations, with respect to a two-symbol tape Turing machine. Implementation of programming languages in neural nets turns to be not only theo...

  1. Interaction Nets in Russian

    OpenAIRE

    Salikhmetov, Anton

    2013-01-01

    Draft translation to Russian of Chapter 7, Interaction-Based Models of Computation, from Models of Computation: An Introduction to Computability Theory by Maribel Fernandez. "In this chapter, we study interaction nets, a model of computation that can be seen as a representative of a class of models based on the notion of 'computation as interaction'. Interaction nets are a graphical model of computation devised by Yves Lafont in 1990 as a generalisation of the proof structures of linear logic...

  2. Programming NET 35

    CERN Document Server

    Liberty, Jesse

    2009-01-01

    Bestselling author Jesse Liberty and industry expert Alex Horovitz uncover the common threads that unite the .NET 3.5 technologies, so you can benefit from the best practices and architectural patterns baked into the new Microsoft frameworks. The book offers a Grand Tour" of .NET 3.5 that describes how the principal technologies can be used together, with Ajax, to build modern n-tier and service-oriented applications. "

  3. Bismuth determination in environmental samples by hydride generation-electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Moscoso-Perez, Carmen; Moreda-Pineiro, Jorge; Lopez-Mahia, Purificacion; Muniategui-Lorenzo, Soledad; Fernandez-Fernandez, Esther; Prada-Rodriguez, Dario [Department of Analytical Chemistry, Faculty of Sciences, University of A Coruna, Campus da Zapateira s/n, E-15071, A Coruna (Spain)

    2003-12-04

    A hydride generation procedure, via flow injection, coupled to electrothermal atomic absorption spectrometry was optimised for Bi determination in sea water and hot-spring water and acid extracts from coal, coal fly ash and slag samples. The effects of several variables such as hydrochloric acid and sodium tetrahydroborate concentrations, hydrochloric acid and sodium tetrahydroborate flow rates, reaction coil length, trapping and atomisation temperatures, trapping time and the Ar flow rate have been investigated by using a 2{sup 9}*3/128 Plackett-Burman design. From these studies, certain variables (sodium tetrahydroborate concentration and trapping time) showed up as significant, and they were optimised by a 2{sup 2}+star central composite design. In addition, a study of the bismuthine trapping and atomisation efficiency from graphite tubes (GTs) permanently treated with uranium, tantalum, lanthanum oxide, niobium, beryllium oxide, chromium oxide and tantalum carbide were investigated. The results obtained were compared with those achieved by iridium and zirconium-treated GTs. The best analytical performances, with characteristic mass of 35 pg and detection limit of 70 ng l{sup -1}, were achieved by using U-treated GTs. Accuracy were checked using several reference materials: 1643d (Trace Elements in Water), TM-24 (Reference Water), GBW-07401 (Soil) and 1632c (Trace Elements in Coal)

  4. The prevalence of bacterial resistance in clinical, food, water and some environmental samples in Southwest Nigeria.

    Science.gov (United States)

    Lateef, A; Oloke, J K; Gueguimkana, E B

    2005-01-01

    The resistance pattern and mechanisms of bacterial isolates obtained from clinical origin, soil, industrial effluent, orange juice products and drinking water were studied using commonly used antibiotics. The microbial load of the water samples, industrial effluent and orange juice products were 1.0 x 10(1)-2.25 x 10(6), 2.15 x 10(5), and 3.5 x 10(4)-2.15 x 10(5) cfu mL(-1), respectively. The faecal coliform test revealed that only two out of twenty orange juice products had MPN of 2 and 20, the MPN of water ranged from 1-> or = 1800, while the effluent had MPN of > or = 1800. The bacterial isolates that were isolated include E. coli, S. aureus, P. vulgaris, S. marcescens, S. pyogenes, B. cereus, B. subtilis, Micrococcus sp., Klebsiella sp., P. aeruginosa, and Enterobacter sp. Also, clinical and soil isolates of P. aeruginosa were used in the study. Among the eight antibiotics tested for resistance on five strains of each bacterium, seven different resistance patterns were observed among the bacterial isolates obtained from water, effluent and orange juice products. Among the clinical and soil isolates of P. aeruginosa, four multiple-drug resistance patterns were obtained. Thirty strains of E. coli and S. aureus were tested for beta-lactamase production and fourteen strains, seven each of E. coli and S. aureus that had high Minimum Inhibitory Concentration values (MIC) for both Amoxycillin and Cloxacillin were positive.

  5. Differentiation Borrelia Species in Environmental Samples with High-Resolution DNA Melting Analysis.

    Science.gov (United States)

    Wodecka, Beata; Skotarczak, Bogumiła

    2015-01-01

    Borrelia burgdorferi sensu lato includes at least 20 species in the world, and half of these are found in Europe. The usefulness of high resolution melting (HRM) analysis of DNA denaturation curves has been assessed for differentiation of Borrelia species. HRM protocol for Borrelia species was used to examine the 77 DNA extracts selected from earlier studies with the use of three different molecular markers: flaB, rplL, and groEL. The studies revealed that the best marker is the groEL gene, which enables identification of 8 Borrelia species, including B. miyamotoi from the relapsing fever borreliae group and 7 of B. burgdorferi s.l. complex (B. garinii, B, afzelii, B. burgdorferi s.s., B. valaisiana, B. lusitaniae, B. bissetii, B. spielmanii). The HRM method, when compared with other PCR variants with regard to the reduced time of analysis, is an alternative for the procedures used in the molecular diagnostics of borreliosis including testing of blood samples or saved Ixodes ticks for the presence and genotyping of Borrelia burgdorferi after biting a patient.

  6. Population structure of Legionella spp. from environmental samples in Gabon, 2013.

    Science.gov (United States)

    Ehrhardt, Jonas; Alabi, Abraham S; Kuczius, Thorsten; Tsombeng, Francis Foguim; Becker, Karsten; Kremsner, Peter G; Schaumburg, Frieder; Esen, Meral

    2015-07-01

    Aquatic environments are the most important source for Legionella spp. infections such as Legionnaires' disease and Pontiac fever. The reservoirs of Legionella spp. are mostly unclear in sub-Saharan Africa. The aim of this study, conducted in 2013, was to identify geographical areas of an increased risk for exposure to Legionella spp., and to describe the population structure of Legionella spp. from different water sources in a cross-sectional study in Gabon. Fresh water samples (n = 200) were cultured on Legionella selective agar; species were confirmed by MALDI-TOF, a Legionella pneumophila specific real-time PCR and 16S RNA gene sequencing. Serogroups were identified by agglutination test. The population structure was assessed by multilocus sequence typing (MLST). Legionella spp. isolates (n = 29) were frequently found in the hospital setting particularly in hot water systems. Open water bodies (i.e. rivers, lakes) were not contaminated with Legionella spp. Isolated L. pneumophila mainly belonged to serogroups 2-14 (n = 19) and MLST sequence type ST1, ST75 (and related STs) and ST1911. In conclusion, hospitalized patients might have an increased risk to become infected with Legionella spp. in the studied areas in Gabon, particularly if they have risk factors such as comorbidities. Both broadly extended (ST1, ST75) and local lineages (ST1911) were present in our setting. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Climatic and environmental records from Altai glaciers, Siberia, recovered from ice-cores and snow samples

    Science.gov (United States)

    Aizen, V. B.; Aizen, E. M.; Kreutz, K. J.; Fujita, K.; Cecil, D.; Nikitin, S. A.

    2002-12-01

    A depth/accumulation scale for the Altai glaciers, Siberia, established based on δ18O and δD firn-ice cores analysis. In sequences of annual layers in the firn-ice cores recovered in 2001 and 2002, the mean annual snow accumulation was found to be 800 mm at 4115 m of the Belukha Snow-Firn Plateau. The transfer function was developed using the seasonality of accumulation layer profile with normalization of data from the nearby meteorological station. The δ18O and δD firn-ice core records compared with meteorological data and indices of atmospheric circulation patterns using regression analyses revealed a dominant source of moisture from Atlantic Ocean during summer and Pacific Ocean moisture during autumn. At the equal air temperatures the most remote source of moisture from Atlantic Ocean resulted in more negative values of δ18O composition under the negative values of North Atlantic Oscillation. Changes in the prevailing atmospheric circulation patterns (e.g., NAO, WPO) over the Altai Mountains are also reflected in the major ions content in snow, firn and ice samples. The anthropogenic emission inventory for Altai glaciers developed using ice-cores and snow pits sulfate and nitrate records.

  8. Extraction and quantification of phosphorus derived from DNA and lipids in environmental samples.

    Science.gov (United States)

    Paraskova, Julia V; Rydin, Emil; Sjöberg, Per J R

    2013-10-15

    Understanding the flux and turnover of phosphorus (P) in the environment is important due to the key role P plays in eutrophication and in the ambition to find cost-effective measures to mitigate it. Orthophosphate diesters, including DNA and phospholipids (PLs), represent a potentially degradable P pool that could support future primary production and eutrophication. In this study, extraction techniques were optimized and combined with colorimetric determination of extracted P to provide a selective quantification method for DNA-P and PL-P in agricultural soil, sediment and composted manure. The proposed method is rapid and reproducible with an RSD of DNA and PL standards, was over 95% for both DNA and PLs. The method can be used for the determination of the pool size of the two organic P fractions. Results show that DNA-P comprises 3.0% by weight of the total P (TP) content in the studied soil, 10.4% in the sediment and 8.4% in the compost samples. The values for PL-P are 0.5%, 6.0% and 1.7% for soil, sediment and compost, respectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Determination of some heavy metals in food and environmental samples by flame atomic absorption spectrometry after coprecipitation.

    Science.gov (United States)

    Soylak, Mustafa; Aydin, Ayse

    2011-06-01

    A novel preconcentration procedure based coprecipitation of Cu(II), Co(II), Cd(II), Ni(II), Mn(II), Fe(III) and Pb(II) on thulium hydroxide precipitate has been presented prior to flame atomic absorption spectrometric determination of them in environmental samples. The analytical parameters that influenced the quantitative coprecipitation of analytes including amount of thulium, pH, duration time, etc. were investigated. The effects of alkali, earth alkali, and some transition metals on the recoveries were also studied. Under the optimized conditions, the detection limits (3 sigma, N=10) for the analytes were in the range of 0.1-1.6 μg/L, respectively. The validation of the presented coprecipitation method was checked by the analysis of certified reference materials (TMDA 54.4 fortified lake water and HR-1 Humber river sediment). The proposed coprecipitation method has been successfully applied for the determination of traces of copper, cobalt, cadmium, nickel, manganese, iron and lead in food and environmental samples. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Smart thorium and uranium determination exploiting renewable solid-phase extraction applied to environmental samples in a wide concentration range

    Energy Technology Data Exchange (ETDEWEB)

    Avivar, Jessica; Ferrer, Laura; Cerda, Victor [University of the Balearic Islands, Chemistry Department, Palma (Spain); Casas, Montserrat [University of the Balearic Islands, Physic Department, IFISC-CSIC, Palma (Spain)

    2011-07-15

    A smart fully automated system is proposed for determination of thorium and uranium in a wide concentration range, reaching environmental levels. The hyphenation of lab-on-valve (LOV) and multisyringe flow injection analysis (MSFIA), coupled to a long path length liquid waveguide capillary cell, allows the spectrophotometric determination of thorium and uranium in different types of environmental sample matrices achieving high selectivity and sensitivity levels. Online separation and preconcentration of thorium and uranium is carried out by means of Uranium and TEtraValents Actinides resin. The potential of the LOV-MSFIA makes possible the full automation of the system by the in-line regeneration of the column and its combination with a smart methodology is a step forward in automation. After elution, thorium(IV) and uranium(VI) are spectrophotometrically detected after reaction with arsenazo-III. We propose a rapid, inexpensive, and fully automated method to determine thorium(IV) and uranium(VI) in a wide concentration range (0-1,200 and 0-2,000 {mu}g L{sup -1} Th and U, respectively). Limits of detection reached are 5.9 {eta}g L{sup -1} of uranium and 60 {eta}g L{sup -1} of thorium. Different water sample matrices (seawater, well water, freshwater, tap water, and mineral water), and a channel sediment reference material which contained thorium and uranium were satisfactorily analyzed with the proposed method. (orig.)

  11. Methods to characterize environmental settings of stream and groundwater sampling sites for National Water-Quality Assessment

    Science.gov (United States)

    Nakagaki, Naomi; Hitt, Kerie J.; Price, Curtis V.; Falcone, James A.

    2012-01-01

    Characterization of natural and anthropogenic features that define the environmental settings of sampling sites for streams and groundwater, including drainage basins and groundwater study areas, is an essential component of water-quality and ecological investigations being conducted as part of the U.S. Geological Survey's National Water-Quality Assessment program. Quantitative characterization of environmental settings, combined with physical, chemical, and biological data collected at sampling sites, contributes to understanding the status of, and influences on, water-quality and ecological conditions. To support studies for the National Water-Quality Assessment program, a geographic information system (GIS) was used to develop a standard set of methods to consistently characterize the sites, drainage basins, and groundwater study areas across the nation. This report describes three methods used for characterization-simple overlay, area-weighted areal interpolation, and land-cover-weighted areal interpolation-and their appropriate applications to geographic analyses that have different objectives and data constraints. In addition, this document records the GIS thematic datasets that are used for the Program's national design and data analyses.

  12. 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.

  13. {sup 15}N metabolic test for the determination of phytotoxic effects of chemicals and contaminated environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Jung, K.; Segner, H.; Schueuermann, G. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Leipzig (Germany). Sektion Chemische Oekotoxikologie; Kaletta, K. [Halle-Wittenberg Univ., Halle (Germany). Inst. fuer Biochemie

    1999-07-01

    A stable isotope {sup 15}N-nitrogen test (ESIMA=Ecotoxicological Stable Isotope Metabolic Assay) was developed to assess biological effects and the potential toxicological hazard of chemicals and contaminated environmental samples on plant metabolism. The assay measures the effect of toxicants on the incorporation of a {sup 15}N labelled tracer into the total nitrogen fraction (both the nonprotein and protein fraction) of plants. Segments of Pisum arvense epicotyls are used as test substrates because of their high metabolic activity. The plant material is incubated under standardised conditions for two hours; subsequently {sup 15}N incorporation is analysed by determining the {sup 15}N abundance ({sup 15}N atom-%) in the epicotyl segments. The effects of toxicants are evaluated by comparing the {sup 15}N incorporation rates of control tissue and epicotyl segments exposed to individual chemicals or complex environmental samples. The specificity and sensitivity of effects as indicated by ESIMA were compared with effect as measured by two establish ecotoxicological bioassays, the pollen tube growth test using pollen of Nicotiana sylvestris and the bacterial luminescence inhibition test using pollen of Photobacterium phosphoreum. The results of the study clearly indicate the suitability of ESIMA for assessing toxic impacts on plant nitrogen metabolism. (orig.)

  14. Activity ratios of {sup 137}Cs, {sup 90}Sr and {sup 239+240}Pu in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Bossew, P. [European Commission - DG Joint Research Centre, Institute for Environment and Sustainability (IES), I-21020 Ispra (Vatican City State, Holy See,) (Italy)], E-mail: peter.bossew@jrc.it; Lettner, H. [Institute of Physics and Biophysics, University of Salzburg, Hellbrunner Strasse 34, A-5020 Salzburg (Austria)], E-mail: herbert.lettner@sbg.ac.at; Hubmer, A.; Erlinger, C.; Gastberger, M. [Institute of Physics and Biophysics, University of Salzburg, Hellbrunner Strasse 34, A-5020 Salzburg (Austria)

    2007-09-15

    Both global and Chernobyl fallout have resulted in environmental contamination with radionuclides such as {sup 137}Cs, {sup 90}Sr and {sup 239+240}Pu. In environmental samples, {sup 137}Cs and {sup 239+240}Pu can be divided into the contributions of either source, if also the isotopes {sup 134}Cs and {sup 238}Pu are measurable, based on the known isotopic ratios in global and Chernobyl fallout. No analogous method is available for {sup 90}Sr. The activity ratios of Sr to Cs and Pu, respectively, are known for the actual fallout mainly from air filter measurements; but due to the high mobility of Sr in the environment, compared to Cs and Pu, these ratios generally do not hold for the inventory many years after deposition. In this paper we suggest a method to identify the mean contributions of global and Chernobyl fallout to total Sr in soil, sediment and cryoconite samples from Alpine and pre-Alpine regions of Austria, based on a statistical evaluation of Sr/Cs/Pu radionuclide activity ratios. Results are given for Sr:Cs, Sr:Pu and Cs:Pu ratios. Comparison with fallout data shows a strong depletion of Sr against Cs and Pu.

  15. Optimization of pressurized liquid extraction (PLE) of dioxin-furans and dioxin-like PCBs from environmental samples.

    Science.gov (United States)

    Antunes, Pedro; Viana, Paula; Vinhas, Tereza; Capelo, J L; Rivera, J; Gaspar, Elvira M S M

    2008-05-30

    Pressurized liquid extraction (PLE) applying three extraction cycles, temperature and pressure, improved the efficiency of solvent extraction when compared with the classical Soxhlet extraction. Polychlorinated-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like PCBs (coplanar polychlorinated biphenyls (Co-PCBs)) in two Certified Reference Materials [DX-1 (sediment) and BCR 529 (soil)] and in two contaminated environmental samples (sediment and soil) were extracted by ASE and Soxhlet methods. Unlike data previously reported by other authors, results demonstrated that ASE using n-hexane as solvent and three extraction cycles, 12.4 MPa (1800 psi) and 150 degrees C achieves similar recovery results than the classical Soxhlet extraction for PCDFs and Co-PCBs, and better recovery results for PCDDs. ASE extraction, performed in less time and with less solvent proved to be, under optimized conditions, an excellent extraction technique for the simultaneous analysis of PCDD/PCDFs and Co-PCBs from environmental samples. Such fast analytical methodology, having the best cost-efficiency ratio, will improve the control and will provide more information about the occurrence of dioxins and the levels of toxicity and thereby will contribute to increase human health.

  16. Enantioseparation and determination of the chiral phenylpyrazole insecticide ethiprole in agricultural and environmental samples and its enantioselective degradation in soil.

    Science.gov (United States)

    Zhang, Qing; Shi, Haiyan; Gao, Beibei; Tian, Mingming; Hua, Xiude; Wang, Minghua

    2016-01-15

    An effective method for the enantioselective determination of ethiprole enantiomers in agricultural and environmental samples was developed. The effects of solvent extraction, mobile phase and thermodynamic parameters for chiral recognition were fully investigated. Complete enantioseparation of the ethiprole enantiomers was achieved on a Lux Cellulose-2 column. The stereochemical structures of ethiprole enantiomers were also determined, and (R)-(+)-ethiprole was first eluted. The average recoveries were 82.7-104.9% with intra-day RSD of 1.7-8.2% in soil, cucumber, spinach, tomato, apple and peach under optimal conditions. Good linearity (R(2)≥0.9991) was obtained for all the matrix calibration curves within a range of 0.1 to 10 mg L(-1). The limits of detection for both enantiomers were estimated to be 0.008 mg kg(-1) in soil, cucumber, spinach and tomato and 0.012 mg kg(-1) in apple and peach, which were lower than the maximum residue levels established in Japan. The results indicate that the proposed method is convenient and reliable for the enantioselective detection of ethiprole in agricultural and environmental samples. The behavior of ethiprole in soil was studied under field conditions and the enantioselective degradation was observed with enantiomer fraction values varying from 0.494 to 0.884 during the experiment. The (R)-(+)-ethiprole (t1/2=11.6 d) degraded faster than (S)-(-)-ethiprole (t1/2=34.7 d). This report is the first describe a chiral analytical method and enantioselective behavior of ethiprole, and these results should be extremely useful for the risk evaluation of ethiprole in food and environmental safety. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. The room temperature preservation of filtered environmental DNA samples and assimilation into a phenol–chloroform–isoamyl alcohol DNA extraction

    Science.gov (United States)

    Renshaw, Mark A; Olds, Brett P; Jerde, Christopher L; McVeigh, Margaret M; Lodge, David M

    2015-01-01

    Current research targeting filtered macrobial environmental DNA (eDNA) often relies upon cold ambient temperatures at various stages, including the transport of water samples from the field to the laboratory and the storage of water and/or filtered samples in the laboratory. This poses practical limitations for field collections in locations where refrigeration and frozen storage is difficult or where samples must be transported long distances for further processing and screening. This study demonstrates the successful preservation of eDNA at room temperature (20 °C) in two lysis buffers, CTAB and Longmire's, over a 2-week period of time. Moreover, the preserved eDNA samples were seamlessly integrated into a phenol–chloroform–isoamyl alcohol (PCI) DNA extraction protocol. The successful application of the eDNA extraction to multiple filter membrane types suggests the methods evaluated here may be broadly applied in future eDNA research. Our results also suggest that for many kinds of studies recently reported on macrobial eDNA, detection probabilities could have been increased, and at a lower cost, by utilizing the Longmire's preservation buffer with a PCI DNA extraction. PMID:24834966

  18. The room temperature preservation of filtered environmental DNA samples and assimilation into a phenol-chloroform-isoamyl alcohol DNA extraction.

    Science.gov (United States)

    Renshaw, Mark A; Olds, Brett P; Jerde, Christopher L; McVeigh, Margaret M; Lodge, David M

    2015-01-01

    Current research targeting filtered macrobial environmental DNA (eDNA) often relies upon cold ambient temperatures at various stages, including the transport of water samples from the field to the laboratory and the storage of water and/or filtered samples in the laboratory. This poses practical limitations for field collections in locations where refrigeration and frozen storage is difficult or where samples must be transported long distances for further processing and screening. This study demonstrates the successful preservation of eDNA at room temperature (20 °C) in two lysis buffers, CTAB and Longmire's, over a 2-week period of time. Moreover, the preserved eDNA samples were seamlessly integrated into a phenol-chloroform-isoamyl alcohol (PCI) DNA extraction protocol. The successful application of the eDNA extraction to multiple filter membrane types suggests the methods evaluated here may be broadly applied in future eDNA research. Our results also suggest that for many kinds of studies recently reported on macrobial eDNA, detection probabilities could have been increased, and at a lower cost, by utilizing the Longmire's preservation buffer with a PCI DNA extraction. © 2014 The Authors. Molecular Ecology Resources Published by John Wiley & Sons Ltd.

  19. Antimony film sensor for sensitive rare earth metal analysis in environmental samples.

    Science.gov (United States)

    Makombe, Martin; van der Horst, Charlton; Silwana, Bongiwe; Iwuoha, Emmanuel; Somerset, Vernon

    2016-07-02

    A sensor for the adsorptive stripping voltammetric determination of rare earth elements has been developed. The electrochemical procedure is based on the oxidation of the rare earth elements complexed with alizarin complexone at a glassy carbon electrode that was in situ modified with an antimony film, during an anodic scan from -0.2 V to 1.1 V (vs. Ag/AgCl) and deposition potential of -0.1 V (vs. Ag/AgCl). The factors influencing the adsorptive stripping capability were optimised, including the complexing agent concentration, plating concentration of antimony and deposition time. The detection of rare earth elements (La, Ce and Pr) were realised in 0.08 M sodium acetate (pH = 5.8) solution as supporting electrolyte, with 2 × 10(-6) M alizarin complexone and 1.0 mg L(-1) antimony solution. Under the optimised conditions, a deposition time of 360 s was obtained and a linear response was observed between 1 and 25 µg L(-1). The reproducibility of the voltammetric measurements was found to be within 5.0% RSD for 12 replicate measurements of cerium(III) concentration of 5 µg L(-1) using the same electrode surface. The detection limits obtained using stripping analysis was 0.06, 0.42 and 0.71 μg L(-1) for Ce(III), La(III) and Pr(III), respectively. The developed sensor has been successfully applied for the determination of cerium, lanthanum and praseodymium in municipal tap water samples.

  20. Joint risk of interbasin water transfer and impact of the window size of sampling low flows under environmental change

    Science.gov (United States)

    Tu, Xinjun; Du, Xiaoxia; Singh, Vijay P.; Chen, Xiaohong; Du, Yiliang; Li, Kun

    2017-11-01

    Constructing a joint distribution of low flows between the donor and recipient basins and analyzing their joint risk are commonly required for implementing interbasin water transfer. In this study, daily streamflow data of bi-basin low flows were sampled at window sizes from 3 to183 days by using the annual minimum method. The stationarity of low flows was tested by a change point analysis and non-stationary low flows were reconstructed by using the moving mean method. Three bivariate Archimedean copulas and five common univariate distributions were applied to fit the joint and marginal distributions of bi-basin low flows. Then, by considering the window size of sampling low flows under environmental change, the change in the joint risk of interbasin water transfer was investigated. Results showed that the non-stationarity of low flows in the recipient basin at all window sizes was significant due to the regulation of water reservoirs. The general extreme value distribution was found to fit the marginal distributions of bi-basin low flows. Three Archimedean copulas satisfactorily fitted the joint distribution of bi-basin low flows and then the Frank copula was found to be the comparatively better. The moving mean method differentiated the location parameter of the GEV distribution, but did not differentiate the scale and shape parameters, and the copula parameters. Due to environmental change, in particular the regulation of water reservoirs in the recipient basin, the decrease of the joint synchronous risk of bi-basin water shortage was slight, but those of the synchronous assurance of water transfer from the donor were remarkable. With the enlargement of window size of sampling low flows, both the joint synchronous risk of bi-basin water shortage, and the joint synchronous assurance of water transfer from the donor basin when there was a water shortage in the recipient basin exhibited a decreasing trend, but their changes were with a slight fluctuation, in

  1. Antimicrobial Susceptibility Patterns of Environmental Streptococci Recovered from Bovine Milk Samples in the Maritime Provinces of Canada

    Directory of Open Access Journals (Sweden)

    Marguerite Cameron

    2016-09-01

    Full Text Available Determination of antimicrobial susceptibility of bovine mastitis pathogens is important for guiding antimicrobial treatment decisions and for the detection of emerging resistance. Environmental streptococci are ubiquitous in the farm environment and are a frequent cause of mastitis in dairy cows. The aim of the study was to determine patterns of antimicrobial susceptibility among species of environmental streptococci isolated from dairy cows in the Maritime Provinces of Canada. The collection consisted of 192 isolates identified in milk samples collected from 177 cows originating from 18 dairy herds. Results were aggregated into: 1 Streptococcus uberis (n = 70, 2 Streptococcus dysgalactiae (n = 28, 3 other Streptococci spp. (n = 35, 4, Lactococcus spp. (n = 32, and 5 Enterococcus spp. (n = 27. Minimum inhibitory concentrations (MIC were determined using the Sensititre microdilution system and mastitis plate format. Multilevel logistic regression models were used to analyze the data, with antimicrobial susceptibility as the outcome. The proportion of susceptible Streptococcus uberis ranged from 23% (for penicillin to 99% (for penicillin/novobiocin, with a median of 82%. All Streptococcus dysgalactiae were susceptible to all antimicrobials except for penicillin (93% susceptible and tetracycline (18% susceptible. The range of susceptibility for other Streptococcus spp. was 43% (for tetracycline to 100%, with a median percent susceptibility of 92%. Lactococcus spp. isolates displayed percent susceptibilities ranging from 0% (for penicillin to 97% (for erythromycin, median 75%. For the antimicrobials tested, the MIC were higher for Enterococcus spp. than for the other species. According to the multilevel models, there was a significant interaction between antimicrobial and bacterial species, indicating that susceptibility against a particular antimicrobial varied among the species of environmental streptococci and vice versa. Generally

  2. Determination of fifteen priority phenolic compounds in environmental samples from Andalusia (Spain) by liquid chromatography-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Vidal, J.L.; Belmonte Vega, A.; Garrido Frenich, A.; Egea Gonzalez, F.J.; Arrebola Liebanas, F.J. [Department of Analytical Chemistry, University of Almeria, 04120 Almeria (Spain)

    2004-05-01

    This work describes the optimisation of a method to determinate fifteen phenolic compounds in waters, sediments and biota (green marine algae) by liquid chromatography coupled to mass spectrometry (LC-MS) with atmospheric pressure chemical ionisation (APCI) in the negative mode. The LC separations of the studied compounds and their MS parameters were optimised in order to improve selectivity and sensitivity. Separation was carried out with a C{sub 18} column using methanol and 0.005% acid acetic as mobile phase in gradient mode. The molecular ion was selected for the quantitation in selective ion monitoring (SIM) mode. A solid-phase extraction (SPE) method was applied in order to preconcentrate the target analytes from water samples. However, extraction of the compounds from sediment and biota samples was carried out by liquid-solid extraction with methanol/water after studying the influence of other organic solvents. In addition, a clean-up step by SPE with HLB Oasis cartridges was necessary for sediments and biota. The proposed analytical methodology was validated in the target environmental matrices by the analysis of spiked blank matrix samples. Detection limits were 10-50 ng L{sup -1} for water, 1-5 {mu}g kg{sup -1} for sediments and 2.5-5 {mu}g kg{sup -1} for biota samples. Good recoveries and precision values were obtained for all matrices. This methodology has been successfully applied to the analysis of incurred water, sediment and biota samples from Andalusia (Spain). (orig.)

  3. Diversity of reductive dehalogenase genes from environmental samples and enrichment cultures identified with degenerate primer PCR screens.

    Directory of Open Access Journals (Sweden)

    Laura Audrey Hug

    2013-11-01

    Full Text Available Reductive dehalogenases are the critical enzymes for anaerobic organohalide respiration, a microbial metabolic process that has been harnessed for bioremediation efforts to resolve chlorinated solvent contamination in groundwater and is implicated in the global halogen cycle. Reductive dehalogenase sequence diversity is informative for the dechlorination potential of the site or enrichment culture. A suite of degenerate PCR primers targeting a comprehensive curated set of reductive dehalogenase genes was designed and applied to twelve DNA samples extracted from contaminated and pristine sites, as well as six enrichment cultures capable of reducing chlorinated compounds to non-toxic end-products. The amplified gene products from four environmental sites and two enrichment cultures were sequenced using Illumina HiSeq, and the reductive dehalogenase complement of each sample determined. The results indicate that the diversity of the reductive dehalogenase gene family is much deeper than is currently accounted for: one-third of the translated proteins have less than 70% pairwise amino acid identity to database sequences. Approximately 60% of the sequenced reductive dehalogenase genes were broadly distributed, being identified in four or more samples, and often in previously sequenced genomes as well. In contrast, 17% of the sequenced reductive dehalogenases were unique, present in only a single sample and bearing less than 90% pairwise amino acid identity to any previously identified proteins. Many of the broadly distributed reductive dehalogenases are uncharacterized in terms of their substrate specificity, making these intriguing targets for further biochemical experimentation. Finally, comparison of samples from a contaminated site and an enrichment culture derived from the same site eight years prior allowed examination of the effect of the enrichment process.

  4. Molecular method for the characterization of Coxiella burnetii from clinical and environmental samples: variability of genotypes in Spain.

    Science.gov (United States)

    Jado, Isabel; Carranza-Rodríguez, Cristina; Barandika, Jesús Félix; Toledo, Álvaro; García-Amil, Cristina; Serrano, Beatriz; Bolaños, Margarita; Gil, Horacio; Escudero, Raquel; García-Pérez, Ana L; Olmeda, A Sonia; Astobiza, Ianire; Lobo, Bruno; Rodríguez-Vargas, Manuela; Pérez-Arellano, José Luis; López-Gatius, Fernando; Pascual-Velasco, Francisco; Cilla, Gustavo; Rodríguez, Noé F; Anda, Pedro

    2012-06-01

    Coxiella burnetii is a highly clonal microorganism which is difficult to culture, requiring BSL3 conditions for its propagation. This leads to a scarce availability of isolates worldwide. On the other hand, published methods of characterization have delineated up to 8 different genomic groups and 36 genotypes. However, all these methodologies, with the exception of one that exhibited limited discriminatory power (3 genotypes), rely on performing between 10 and 20 PCR amplifications or sequencing long fragments of DNA, which make their direct application to clinical samples impracticable and leads to a scarce accessibility of data on the circulation of C. burnetii genotypes. To assess the variability of this organism in Spain, we have developed a novel method that consists of a multiplex (8 targets) PCR and hybridization with specific probes that reproduce the previous classification of this organism into 8 genomic groups, and up to 16 genotypes. It allows for a direct characterization from clinical and environmental samples in a single run, which will help in the study of the different genotypes circulating in wild and domestic cycles as well as from sporadic human cases and outbreaks. The method has been validated with reference isolates. A high variability of C. burnetii has been found in Spain among 90 samples tested, detecting 10 different genotypes, being those adaA negative associated with acute Q fever cases presenting as fever of intermediate duration with liver involvement and with chronic cases. Genotypes infecting humans are also found in sheep, goats, rats, wild boar and ticks, and the only genotype found in cattle has never been found among our clinical samples. This newly developed methodology has permitted to demonstrate that C. burnetii is highly variable in Spain. With the data presented here, cattle seem not to participate in the transmission of C. burnetii to humans in the samples studied, while sheep, goats, wild boar, rats and ticks share

  5. Reveal Salmonella 2.0 test for detection of Salmonella spp. in foods and environmental samples. Performance Tested Method 960801.

    Science.gov (United States)

    Hoerner, Rebecca; Feldpausch, Jill; Gray, R Lucas; Curry, Stephanie; Islam, Zahidul; Goldy, Tim; Klein, Frank; Tadese, Theodros; Rice, Jennifer; Mozola, Mark

    2011-01-01

    Reveal Salmonella 2.0 is an improved version of the original Reveal Salmonella lateral flow immunoassay and is applicable to the detection of Salmonella enterica serogroups A-E in a variety of food and environmental samples. A Performance Tested Method validation study was conducted to compare performance of the Reveal 2.0 method with that of the U.S. Department of Agriculture-Food Safety and Inspection Service or U.S. Food and Drug Administration/Bacteriological Analytical Manual reference culture methods for detection of Salmonella spp. in chicken carcass rinse, raw ground turkey, raw ground beef, hot dogs, raw shrimp, a ready-to-eat meal product, dry pet food, ice cream, spinach, cantaloupe, peanut butter, stainless steel surface, and sprout irrigation water. In a total of 17 trials performed internally and four trials performed in an independent laboratory, there were no statistically significant differences in performance of the Reveal 2.0 and reference culture procedures as determined by Chi-square analysis, with the exception of one trial with stainless steel surface and one trial with sprout irrigation water where there were significantly more positive results by the Reveal 2.0 method. Considering all data generated in testing food samples using enrichment procedures specifically designed for the Reveal method, overall sensitivity of the Reveal method relative to the reference culture methods was 99%. In testing environmental samples, sensitivity of the Reveal method relative to the reference culture method was 164%. For select foods, use of the Reveal test in conjunction with reference method enrichment resulted in overall sensitivity of 92%. There were no unconfirmed positive results on uninoculated control samples in any trials for specificity of 100%. In inclusivity testing, 102 different Salmonella serovars belonging to serogroups A-E were tested and 99 were consistently positive in the Reveal test. In exclusivity testing of 33 strains of non

  6. Quantification and size characterisation of silver nanoparticles in environmental aqueous samples and consumer products by single particle-ICPMS.

    Science.gov (United States)

    Aznar, Ramón; Barahona, Francisco; Geiss, Otmar; Ponti, Jessica; José Luis, Tadeo; Barrero-Moreno, Josefa

    2017-12-01

    Single particle-inductively coupled plasma mass spectrometry (SP-ICPMS) is a promising technique able to generate the number based-particle size distribution (PSD) of nanoparticles (NPs) in aqueous suspensions. However, SP-ICPMS analysis is not consolidated as routine-technique yet and is not typically applied to real test samples with unknown composition. This work presents a methodology to detect, quantify and characterise the number-based PSD of Ag-NPs in different environmental aqueous samples (drinking and lake waters), aqueous samples derived from migration tests and consumer products using SP-ICPMS. The procedure is built from a pragmatic view and involves the analysis of serial dilutions of the original sample until no variation in the measured size values is observed while keeping particle counts proportional to the dilution applied. After evaluation of the analytical figures of merit, the SP-ICPMS method exhibited excellent linearity (r2>0.999) in the range (1-25) × 104 particlesmL-1 for 30, 50 and 80nm nominal size Ag-NPs standards. The precision in terms of repeatability was studied according to the RSDs of the measured size and particle number concentration values and a t-test (p = 95%) at the two intermediate concentration levels was applied to determine the bias of SP-ICPMS size values compared to reference values. The method showed good repeatability and an overall acceptable bias in the studied concentration range. The experimental minimum detectable size for Ag-NPs ranged between 12 and 15nm. Additionally, results derived from direct SP-ICPMS analysis were compared to the results conducted for fractions collected by asymmetric flow-field flow fractionation and supernatant fractions after centrifugal filtration. The method has been successfully applied to determine the presence of Ag-NPs in: lake water; tap water; tap water filtered by a filter jar; seven different liquid silver-based consumer products; and migration solutions (pure water and

  7. Development of magnetic graphene @hydrophilic polydopamine for the enrichment and analysis of phthalates in environmental water samples.

    Science.gov (United States)

    Wang, Xianying; Song, Guoxin; Deng, Chunhui

    2015-01-01

    Magnetic graphene @hydrophilic polydopamine composites were successfully fabricated via a simple solvothermal reaction and self-polymerization of dopamine. Benefit from the excellent characteristics of strong magnetic responsivity, super-hydrophilicity and abundant π-electron system, the prepared material showed great potential as a magnetic solid phase extraction (MSPE) sorbent. In this work, six kinds of phthalates (PAEs) were selected as the target analytes to evaluate the extraction ability of the adsorbents combined with MSPE-GC-MS. And various extraction parameters were optimized by selecting the pH value of samples, the amount of sorbents, adsorption and desorption time, the type and volume of eluting solution. Meanwhile, the whole extraction process could be finished in 30 min. Under the optimized conditions, validations of the method were evaluated as well. And the results presented excellent linearity with a wide range of 50-20,000 μg/L (R(2)>0.9991). The detection of limits were in the range from 0.05-5 μg/L (S/N=3). Therefore, the novel magnetic graphene@polydopamine composites were successfully used as the sorbents for the enrichment and analysis of PAEs in real water samples. This proposed method provided a simple, efficient and sensitive approach for the determination of aromatic compounds in real environmental samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Colorimetric biomimetic sensor systems based on molecularly imprinted polymer membranes for highly-selective detection of phenol in environmental samples

    Directory of Open Access Journals (Sweden)

    Sergeyeva T. A.

    2014-05-01

    Full Text Available Aim. Development of an easy-to-use colorimetric sensor system for fast and accurate detection of phenol in envi- ronmental samples. Methods. Technique of molecular imprinting, method of in situ polymerization of molecularly imprinted polymer membranes. Results. The proposed sensor is based on free-standing molecularly imprinted polymer (MIP membranes, synthesized by in situ polymerization, and having in their structure artificial binding sites capable of selective phenol recognition. The quantitative detection of phenol, selectively adsorbed by the MIP membranes, is based on its reaction with 4-aminoantipyrine, which gives a pink-colored product. The intensity of staining of the MIP membrane is proportional to phenol concentration in the analyzed sample. Phenol can be detected within the range 50 nM–10 mM with limit of detection 50 nM, which corresponds to the concentrations that have to be detected in natural and waste waters in accordance with environmental protection standards. Stability of the MIP-membrane-based sensors was assessed during 12 months storage at room temperature. Conclusions. The sensor system provides highly-selective and sensitive detection of phenol in both mo- del and real (drinking, natural, and waste water samples. As compared to traditional methods of phenol detection, the proposed system is characterized by simplicity of operation and can be used in non-laboratory conditions.

  9. Tandem Extraction/Liquid Chromatography-Mass Spectrometry Protocol for the Analysis of Acrylamide and Surfactant-related Compounds in Complex Aqueous Environmental Samples

    Science.gov (United States)

    The development of a liquid chromatography‐mass spectrometry (LC‐MS)‐based strategy for the detection and quantitation of acrylamide and surfactant‐related compounds in aqueous complex environmental samples.

  10. Prevalence and molecular characterization of Cryptosporidum spp. and Giardia spp. in environmental samples in Hanam province, Vietnam

    DEFF Research Database (Denmark)

    Nguyen, Tram Thuy; Traub, Rebecca J.; Pham, Phuc Duc

    2016-01-01

    Cryptosporidium and Giardia are protozoan parasites that cause human diarrheal disease worldwide. This study was done to evaluate the prevalence and concentrations of these protozoa in environmental samples in Hanam, Vietnam and to assess potential contamination sources using molecular...

  11. The use of at-sea-sampling data to dissociate environmental variability in Norway lobster (Nephrops norvegicus) catches to improve resource efficiency

    DEFF Research Database (Denmark)

    Feekings, Jordan P.; Christensen, Asbjørn; Jonsson, Patrik

    2014-01-01

    The primary aim of this study was to determine whether the information collected as part of the at-sea-sampling program could be used to identify hydrographical and environmental variables that are influential on catch rates of Norway lobster. Ultimately, we wanted to know whether environmental...

  12. Rapid determination of nine parabens and seven other environmental phenols in urine samples of German children and adults.

    Science.gov (United States)

    Moos, Rebecca K; Angerer, Jürgen; Wittsiepe, Jürgen; Wilhelm, Michael; Brüning, Thomas; Koch, Holger M

    2014-11-01

    We developed a fast, selective and sensitive on-line LC/LC-MS/MS method for the simultaneous determination of nine parabens and seven environmental phenols in urine. Parabens are widely used as antimicrobial preservatives. Bisphenol A, triclosan, triclocarban, 2-phenylphenol, and benzophenones are used inter alia in disinfectants, sunscreens and in polymers. Some of these substances are suspected endocrine disruptors. Limits of quantification and analytical quality criteria fully met the needs for determining exposure levels occurring in the general population. We analyzed 157 spot urine samples from the general German population (59 females, 39 males and 59 children). For the parabens, we found methyl, ethyl and n-propyl paraben with high detection rates (77-98%), followed by n-butyl (36%), iso-butyl (17%), iso-propyl (3%) and benzyl paraben (3%). We detected no pentyl and heptyl paraben. Urinary concentrations were highest for methyl paraben (median 24.5 μg/L; 95th percentile 379 μg/L) followed by ethyl (1.4 μg/L; 35.2 μg/L) and n-propyl paraben (1.2 μg/L; 68.1 μg/L). Other environmental phenols with high detection rates were BPA (95%), triclosan (45%) and benzophenone 1 and 3 (26%). For most of the parabens/environmental phenols we found higher urinary levels in females than in males or children, probably due to differences in (personal care) product use. However, high levels (in the mg/L range) were also observed in children. Exposure to the above substances is occurring worldwide. Differences between countries do seem to exist and might be caused by different product compositions or different use habits. Human metabolism data is urgently needed to extrapolate from urinary biomarker levels to doses actually taken up. Copyright © 2014 Elsevier GmbH. All rights reserved.

  13. Identification of a Plasmid-Mediated Quinolone Resistance Gene in Salmonella Isolates from Texas Dairy Farm Environmental Samples.

    Science.gov (United States)

    Cummings, K J; Rodriguez-Rivera, L D; Norman, K N; Ohta, N; Scott, H M

    2017-06-01

    A recent increase in plasmid-mediated quinolone resistance (PMQR) has been detected among Salmonella isolated from humans in the United States, and it is necessary to determine the sources of human infection. We had previously isolated Salmonella from dairy farm environmental samples collected in Texas, and isolates were tested for anti-microbial susceptibility. Two isolates, serotyped as Salmonella Muenster, showed the discordant pattern of nalidixic acid susceptibility and intermediate susceptibility to ciprofloxacin. For this project, whole-genome sequencing of both isolates was performed to detect genes associated with quinolone resistance. The plasmid-mediated qnrB19 gene and IncR plasmid type were identified in both isolates. To our knowledge, this is the first report of PMQR in Salmonella isolated from food animals or agricultural environments in the United States. © 2016 Blackwell Verlag GmbH.

  14. Fast, high-yield synthesis of amphiphilic Ag nanoclusters and the sensing of Hg(2+) in environmental samples.

    Science.gov (United States)

    Xia, Nan; Yang, Jie; Wu, Zhikun

    2015-06-14

    We report the high-yield (74%) synthesis of Ag30(Capt)18 (abbreviated as Ag30) in a very time-saving fashion (half an hour). The cluster composition was determined by high-resolution mass spectrometry combined with TG analysis, and the structure was probed by 1D and 2D NMR. Interestingly, the nanoclusters can dissolve in water and methanol, as well as in most organic solvents such as ethanol, acetone, acetonitrile, dichloromethane and ethyl acetate with the assistance of acetic acid. Such a good solubility in a range of various polar solvents was not reported previously in nanoclusters' research and is important for applications. An important result from this work is that Ag30 can sense a low concentration of Hg(2+) in environmental samples (including lake water and soil solution), indicating that Ag30 can be a potential colorimetric probe for Hg(2+). The sensing mechanism was revealed to be related to the anti-galvanic reduction process.

  15. Evaluation of 2,6-diacetylpyridinebis-4-phenyl-3-thiosemicarbazone as complexing reagent for zinc in food and environmental samples

    Directory of Open Access Journals (Sweden)

    S. Adi Narayana Reddy

    2016-09-01

    Full Text Available An evaluation of analytical reagent, 2,6-diacetylpyridine-bis-4-phenyl-3-thiosemicarbazone (2,6-DAPBPTSC for traces of Zn(II in foods and environmental samples by the development of a simple, sensitive and selective extractive spectrophotometric method was undertaken. It gave a 1:1(M:L Zn(II–2,6-DAPBPTSC yellowish orange colored complex at pH 4.5, was easily extractable into n-butanol and has shown maximum absorbance at 490 nm. It obeys Beer’s law in the range of 1.06–13.6 μg mL−1 of Zn(II. The molar absorptivity, Sandell’s sensitivity and detection limit were found to be 0.471 × 104 L mol−1 cm−1, 0.0138 μg cm−2 and 0.0081 μg mL−1, respectively. The correlation co-efficient of the complex (r = 0.985 indicates good linearity between two variables such as absorbance of complex and amount of zinc. The proposed procedure was applied to traces of Zn(II in foods and environmental samples. Results were compared with those obtained using an AAS and statical validation of the method was tested in terms of Student ‘T’ test and variance ‘F’ test, which indicate the significance of the present method.

  16. La plataforma .NET

    OpenAIRE

    Fornas Estrada, Miquel

    2008-01-01

    L'aparició de la plataforma .NET Framework ha suposat un canvi molt important en la forma de crear i distribuir aplicacions, degut a que incorpora una sèrie d'innovacions tècniques i productives que simplifiquen molt les tasques necessàries per desenvolupar un projecte. La aparición de la plataforma. NET Framework ha supuesto un cambio muy importante en la forma de crear y distribuir aplicaciones, debido a que incorpora una serie de innovaciones técnicas y productivas que simplifican mucho...

  17. Biological Petri Nets

    CERN Document Server

    Wingender, E

    2011-01-01

    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  18. In-port derivatization coupled to different extraction techniques for the determination of alkylphenols in environmental water samples.

    Science.gov (United States)

    Cavalheiro, J; Monperrus, M; Amouroux, D; Preud'Homme, H; Prieto, A; Zuloaga, O

    2014-05-02

    Large volume injection (LVI)-in port silylation coupled to gas chromatography-mass spectrometry (GC-MS) for the determination of alkylphenols (APs) in water samples applying four different extraction approaches was evaluated. Among the variables studied for in-port derivatization, vent time, cryo-focusing temperature and the ratio solvent volume/N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) volume were optimized using an experimental design approach. Regarding the extraction techniques, different approaches previously optimized in the research group were tested. On the one hand different polymeric materials were tested: silicon rod (SR), polyethersulfone (PES) and polydimethylsiloxane (PDMS), the latter in the stir-bar sorptive extraction format (SBSE-PDMS). PES was chosen among the polymeric materials due to the higher recoveries (compared with SR) and lower price (compared to PDMS in the stir-bar sorptive extraction, SBSE-PDMS). Both MASE and PES protocols were selected at this point for further method validation and application to real samples. Finally, the developed methods were validated and applied to the determination of target analytes in various aqueous environmental matrices, including estuarine water and wastewater. Acceptable repeatability in the case of MASE (5-17%) and PES (7-21%) procedures and method detection limits (MDLs, 5-123 and 28-328 ng L(-1) for PES and MASE, respectively) were obtained for most analytes. In terms of apparent recoveries in the presence of matrix, estuarine and effluent samples showed no significant matrix effect (apparent recoveries in the 73-121% for PES and 74-128% for MASE), while a stronger matrix effect was observed for influent wastewater samples (98-132% for PES and 65-156% for MASE). Both MASE and PES extractions combined with LVI-in-port derivatization-GC-MS were applied to the determination of APs in the estuary of Bilbao (Gulf of Biscay, Spain). Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Enantioseparation and determination of the chiral phenylpyrazole insecticide ethiprole in agricultural and environmental samples and its enantioselective degradation in soil

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qing; Shi, Haiyan; Gao, Beibei; Tian, Mingming; Hua, Xiude; Wang, Minghua, E-mail: wangmha@njau.edu.cn

    2016-01-15

    An effective method for the enantioselective determination of ethiprole enantiomers in agricultural and environmental samples was developed. The effects of solvent extraction, mobile phase and thermodynamic parameters for chiral recognition were fully investigated. Complete enantioseparation of the ethiprole enantiomers was achieved on a Lux Cellulose-2 column. The stereochemical structures of ethiprole enantiomers were also determined, and (R)-(+)-ethiprole was first eluted. The average recoveries were 82.7–104.9% with intra-day RSD of 1.7–8.2% in soil, cucumber, spinach, tomato, apple and peach under optimal conditions. Good linearity (R{sup 2} ≥ 0.9991) was obtained for all the matrix calibration curves within a range of 0.1 to 10 mg L{sup −1}. The limits of detection for both enantiomers were estimated to be 0.008 mg kg{sup −1} in soil, cucumber, spinach and tomato and 0.012 mg kg{sup −1} in apple and peach, which were lower than the maximum residue levels established in Japan. The results indicate that the proposed method is convenient and reliable for the enantioselective detection of ethiprole in agricultural and environmental samples. The behavior of ethiprole in soil was studied under field conditions and the enantioselective degradation was observed with enantiomer fraction values varying from 0.494 to 0.884 during the experiment. The (R)-(+)-ethiprole (t{sub 1/2} = 11.6 d) degraded faster than (S)-(−)-ethiprole (t{sub 1/2} = 34.7 d). This report is the first describe a chiral analytical method and enantioselective behavior of ethiprole, and these results should be extremely useful for the risk evaluation of ethiprole in food and environmental safety. - Highlights: • The ethiprole enantiomers were completely separated. • A novel method for enantioselective determination of ethiprole was developed. • The absolute configurations of ethiprole enantiomers were firstly determined. • The (R)-(+)-ethiprole was preferentially degraded in

  20. pH(stat) vs. single extraction tests to evaluate heavy metals and arsenic leachability in environmental samples.

    Science.gov (United States)

    Rigol, A; Mateu, J; González-Núñez, R; Rauret, G; Vidal, M

    2009-01-19

    Here we compared the pH(stat) test, which examines the leachability of major elements (Ca, Mg, Al, Fe, and Mn), dissolved organic carbon, and trace elements (Cd, Zn, Cu, Pb, and As) in a wide pH range, with single extraction tests based on the use of mild extractants (calcium chloride, acetic acid or EDTA). For this purpose, we examined samples from a variety of environmental conditions (sludges, mineral soils, organic soils, and soils with particulate and/or soluble contamination). Extraction yields obtained with CaCl(2) (0.01 mol L(-1)) and CH(3)COOH (0.43 mol L(-1)) correlated well with those from the pH(stat) at the same pH (r=0.98 and 0.95, respectively), while the use of EDTA (0.05 mol L(-1)) led to systematically higher extraction yields than those quantified with the pH(stat) at the same pH. However, the pH(stat) test had three distinct advantages: (1) it revealed the relationship between the solubility of the main soil phases and pH; (2) it showed the variation in pollutant leachability due to changes in pH; and (3) it better predicted the maximum contaminant availability. Thus we propose that the pH(stat) is the best laboratory tests to evaluate the contaminant leachability over a wide range of sample types (soil, sludge, and sediment).

  1. Analysis of pesticides residues in environmental water samples using multiwalled carbon nanotubes dispersive solid-phase extraction.

    Science.gov (United States)

    González-Curbelo, Miguel Ángel; Herrera-Herrera, Antonio V; Hernández-Borges, Javier; Rodríguez-Delgado, Miguel Ángel

    2013-02-01

    In this manuscript, a dispersive SPE method based on the use of multiwalled carbon nanotubes has been developed for the determination of 15 organophosphorus pesticides residues including some of their metabolites (disulfoton sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos sulfone, disulfoton sulfone, and fensulfothion) from real environmental waters (run-off, mineral and tap water) by GC with nitrogen phosphorus detection. Factors that affect the enrichment efficiency such as sample volume, multiwalled carbon nanotubes amount, and volume of eluent were studied. The optimized method was validated in terms of matrix-matched calibration, recovery, precision, and accuracy for the three analyzed samples. In this last case, the developed Student's t test demonstrated that there were no significant differences between real and spiked concentrations. Optimum dispersive SPE conditions (extraction of 200 mL of water, pH 6.0, with 130 mg of multiwalled carbon nanotubes, elution with 25 mL of dichloromethane for run-off and tap water and 30 mL for mineral water) allowed the quantitative extraction of analytes at levels lower than the maximum residues limits legislated by the European Union, with LODs between 1.16 and 93.6 ng/L. Absolute recovery values achieved were in the range of 67-107% (RSD values <10.1%). © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Zn(II)-concentration dependent Raman spectra in the dithizone complex on gold nanoparticle surfaces in environmental water samples

    Science.gov (United States)

    Ly, Nguyen Hoang; Joo, Sang-Woo

    2015-11-01

    After the formation of dithizone with metal ion complexes, a selective Raman detection method for the Zn2+ ions in aqueous solutions was developed by observing the intensity change of the ring mode peaks at ∼1585 cm-1 on gold nanoparticles (AuNPs). At high concentrations of Zn2+ ions, the conformation of the dithizone complex may have different orientations on AuNPs to yield the spectral changes at ca. ∼510 and ∼1585 cm-1. The concentration dependent spectra changes indicated that a detection limit would be in the submicromolar region of Zn2+ ions. The other ions of Mg2+, K+, Fe3+, Hg2+, Co2+, Fe2+, Pb2+, Cu2+, Ni2+, Cr3+, NH4+, Cd2+, Na+, Ca2+, and Mn2+ at micromolar concentrations of 1 μM did not produce such spectral changes. The detection limit based on the Raman band intensities was estimated to be as low as 500 nM of Zn2+ ion in aqueous solutions. The three real samples of tap, river, and seawater were tested under the interference of the commonly existing interfering ions. Despite the presence of highly concentrated Na, Ca, Mg, and K, our interfacial spectroscopic methodology of Zn2+ determination could be applied in the environmental water samples.

  3. A membraneless gas-diffusion unit-multisyringe flow injection spectrophotometric method for ammonium determination in untreated environmental samples.

    Science.gov (United States)

    Almeida, M Inês G S; Estela, José Manuel; Segundo, Marcela A; Cerdà, Víctor

    2011-06-15

    A new design of a membraneless gas-diffusion (MGD) unit coupled to a multisyringe flow injection system is proposed. The spectrophotometric determination of ammonium using an acid-base indicator was chosen to show the feasibility of this approach. Hence, in alkaline medium, ammonium ions are transformed into ammonia (donor channel) which diffuses through the headspace into the acceptor stream (bromothymol blue solution), causing a pH change and subsequently a colour change. The exploitation of the enhanced potentialities of this re-designed MGD device was the main purpose of the present work. Hence, several strategies concerning flow management were studied seeking to characterize and improve the analytical features of the methodology and moreover, untreated environmental samples were analysed without previous filtration. Consequently, stopped flow in acceptor channel with continuous flow in donor channel was chosen for the application to wastewater and spiked river water samples. A linear concentration range between 10.0 and 50.0 mg L(-1) of NH(4)(+), a limit of detection of 2.20 mg L(-1) and a determination frequency of 11h(-1) were obtained. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Petri Nets-Applications

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 9. Petri Nets - Applications. Y Narahari. General Article Volume 4 Issue 9 September 1999 pp 44-52. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/004/09/0044-0052. Author Affiliations. Y Narahari ...

  5. Safety nets or straitjackets?

    DEFF Research Database (Denmark)

    Ilsøe, Anna

    2012-01-01

    Does regulation of working hours at national and sector level impose straitjackets, or offer safety nets to employees seeking working time flexibility? This article compares legislation and collective agreements in the metal industries of Denmark, Germany and the USA. The industry has historically...

  6. Coloured Petri Nets

    CERN Document Server

    Jensen, Kurt

    2009-01-01

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. This book introduces the constructs of the CPN modelling language and presents the related analysis methods. It provides a comprehensive road map for the practical use of CPN.

  7. Boom Booom Net Radio

    DEFF Research Database (Denmark)

    Grimshaw, Mark Nicholas; Yong, Louisa; Dobie, Ian

    1999-01-01

    of an existing Internet radio station; Boom Booom Net Radio. Whilst necessity dictates some use of technology-related terminology, wherever possible we have endeavoured to keep such jargon to a minimum and to either explain it in the text or to provide further explanation in the appended glossary....

  8. Game Theory .net.

    Science.gov (United States)

    Shor, Mikhael

    2003-01-01

    States making game theory relevant and accessible to students is challenging. Describes the primary goal of GameTheory.net is to provide interactive teaching tools. Indicates the site strives to unite educators from economics, political and computer science, and ecology by providing a repository of lecture notes and tests for courses using…

  9. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kristensen, Lars Michael

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. The development of such systems is particularly challenging because of inherent intricacies like possible nondeterminism...

  10. Data Sources for NetZero Ft Carson Model

    Data.gov (United States)

    U.S. Environmental Protection Agency — Table of values used to parameterize and evaluate the Ft Carson NetZero integrated Model with published reference sources for each value. This dataset is associated...

  11. RadNet Real-Time Monitoring Spectrometry Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The RadNet Real-Time Monitoring Spectrometry Data Inventory contains measured data used to identify and measure specific radioactive materials in the atmosphere at...

  12. Graphene aerogel based monolith for effective solid-phase extraction of trace environmental pollutants from water samples.

    Science.gov (United States)

    Han, Qiang; Liang, Qionglin; Zhang, Xiaoqiong; Yang, Liu; Ding, Mingyu

    2016-05-20

    Graphene aerogel (GA), a typical kind of three-dimensional (3D) macroscopic assembly, not only provides inherently excellent properties of graphene sheets (GS), but also exhibits interesting characteristics of the 3D macroporous architecture including large and tunable pore volumes, high specific surface areas and fast mass transport kinetics. Thus, it is rational to expect GA to be an efficient adsorbent for solid-phase extraction (SPE). In this paper, a novel GA monolith based solid-phase extraction method was investigated in the application of environment analysis. The GA monolith based SPE cartridge was fabricated directly in the empty cartridge through template-free "sol-cryo" method. Due to the efficient mass transfer, more adsorption sites as well as effective retention for the analytes, the adsorption property of GA for bisphenol A revealed better performance than that of GS. What's more, GA also outperformed in loading and eluting for target analysis. On the basis of the above advantages, the obtained cartridge was applied for the separation of environmental pollutants from water samples. Taking endocrine disrupting chemicals and polychlorinated biphenyls as the polar and weak polar model analytes, optimizing several parameters influencing the recoveries, limits of detection in the range of 0.01-0.11ngmL(-1) and 0.19-1.53ngL(-1) for the two series of compounds were provided by the established methods. The satisfied sensitivity was accessed and recoveries ranging from 76.3 to 112.5% were obtained for all the analytes when the proposed methods were applied in real water samples analysis. The results revealed the potential of GA as an effective sorbent in sample preparation processes. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Influence of sample temperature and environmental humidity on measurements of benzene in ambient air by transportable GC-PID

    Science.gov (United States)

    Romero-Trigueros, Cristina; Doval Miñarro, Marta; González Duperón, Esther; González Ferradás, Enrique

    2017-10-01

    Calibration of in situ analysers of air pollutants is usually done with dry standards. In this paper, the influence of sample temperature and environmental humidity on benzene measurements by gas chromatography coupled with a photoionisation detector (GC-PID) is studied. Two reference gas mixtures (40 and 5 µg m-3 nominal concentration benzene in air) were subjected to two temperature cycles (20/5/20 °C and 20/35/20 °C) and measured with two identical GC-PIDs. The change in sample temperature did not produce any significant change in readings. Regarding ambient humidity, the chromatographs were calibrated for benzene with dry gases and subjected to measure reference standards with humidity (20 and 80 % at 20 °C). When measuring a concentration of 0.5 µg m-3 benzene in air, the levels of humidity tested did not produce any significant interference in measurements taken with any of the analysers. However, when measuring a concentration of 40 µg m-3, biases in measurements of 18 and 21 % for each respective analyser were obtained when the relative humidity of the sample was 80 % at 20 °C. Further tests were carried out to study the nature of this interference. Results show that humidity interference depends on both the amount fractions of water vapour and benzene. If benzene concentrations in an area are close to its annual limit value (5 µg m-3), biases of 2.2 % can be expected when the absolute humidity is 8.6 g cm-3 - corresponding to a relative humidity of 50 % at 20 °C. This can be accounted for in the uncertainty budget of measurements with no need for corrections. If benzene concentrations are above the annual limit value, biases become higher. Thus, in these cases, actions should be taken to reduce the humidity interference, as an underestimation of benzene concentrations may cause a mismanagement of air quality in these situations.

  14. Influence of selective media on successful detection of Shiga toxin-producing Escherichia coli in food, fecal, and environmental samples.

    Science.gov (United States)

    Hussein, Hussein S; Bollinger, Laurie M

    2008-06-01

    Shiga toxin-producing Escherichia coli (STEC) strains have caused a large number of human illness outbreaks worldwide. In most cases, the infection was traced to consumption of meats or vegetables contaminated with cattle feces. To combat this public health problem, pre- and post-harvest control strategies are continuously implemented to assure food safety. Thus, rapid, reliable, and sensitive methods for STEC detection must be available to provide confidence not only in the meats or vegetables entering the food chain but also in testing humans with illnesses. As a result, enrichment for STEC has been a critical step in any successful protocol for their detection. The base media commonly used for STEC enrichment include sorbitol MacConkey agar, tryptic soy broth (TSB), E. coli broth, enterohemorrhagic E. coli broth, buffered peptone water (BPW), and brain heart infusion broth. In addition to bile salts, antibiotics (e.g., tellurite, cefixime, novobiocin, vancomycin, cefsulodin, and acriflavin) are used at different concentrations to enrich for STEC. In most published reports, however, the reasons for choosing the selective medium were not provided. Thus, this review was intended to evaluate the base media and antibiotics commonly used for STEC detection. The efficacy of a detection method will certainly depend on the choice of the base medium, selective agents, and their concentrations. The interactions among these factors are also expected to affect sensitivity of the detection method, especially when the test sample contains a small number of STEC cells. Because sensitivity of detection is expected to decline when testing for stressed or injured STEC cells, as is the case in environmental samples, a pre-enrichment step in TSB or BPW without antibiotics may be necessary. Future research should focus on identifying possible antibiotic combinations that effectively inhibit most background bacteria without affecting pathogenic STEC strains in the test sample.

  15. Characterizing fallout material using Cs and Pu atom ratios in environmental samples from the FDNPP fallout zone

    Science.gov (United States)

    Richards, David; Dunne, James; Martin, Peter; Scott, Tom; Yamashiki, Yosuke; Coath, Chris; Chen, Hart

    2017-04-01

    Here we report the use of combined of Cs and Pu isotope measurements to investigate the extensive plumes of radioactive fallout from the disaster at Fukishima Daiichi nuclear power plant (FNDPP) in March 2011. Among the aims of our study are improved assessment of the physico-chemical nature and changing distribution of land-based fallout. 135Cs/137Cs and 134Cs/137Cs atom ratios are indicative of conditions that relate to the nuclear fission reactions responsible for producing the respective radiocaesium isotopes, and offer much more in terms of forensic and chronological analysis than monitoring 137Cs alone. We briefly present methods to quantify the atom ratios of Cs and Pu isotopes in soil, lichen and moss samples from FDNPP catchment using mass spectrometry (ThermoTRITON for Cs and ThermoNEPTUNE for Pu). High precision data from Fukushima are presented (e.g decay corrected 135Cs/137Cs atom ratio = 0.384 ± 0.001 (n = 5) for roadside dust from Iitate region), and these are in agreement with prelimary estimates by others. We also confirm results for IAEA-330, a spinach sample collected from Polesskoe, Ukraine and subject to contamination from the Chernobyl accident. In addition to Cs isotopes, we adopt Pu isotopes to add a further dimension to the forensic analysis. We discuss the corrections required for background levels prior to the disaster, possibility for multiple components of fallout and complicating factors associated with remobilisation during the clean-up operation. In parallel with this work on digests and leaches from bulk environmental samples, we are refining methods for particle identification, isolation and characterisation using a complementary sequence of cutting-edge materials and manipulation techniques, including combined electron microscopy, focused ion beam techniques (Dualbeam), nano/micro manipulators and nano-scale imaging x-ray photoelectron spectroscopy (NanoESCA) and microCT.

  16. Can the collection of expired long-lasting insecticidal nets reduce their coverage and use? Sociocultural aspects related to LLIN life cycle management and use in four districts in Madagascar.

    Science.gov (United States)

    Ramanantsoa, Ambinina; Wilson-Barthes, Marta; Rahenintsoa, Rindra; Hoibak, Sarah; Ranaivoharimina, Harilala; Rahelimalala, Martha Delphine; Rakotomanga, Avotiana; Finlay, Alyssa; Muela Ribera, Joan; Peeters Grietens, Koen

    2017-10-10

    There is growing awareness of the likely impact increased numbers of LLINs will have on the environment, if not disposed of or recycled appropriately. As part of a World Health Organization (WHO) and United Nations Environment Programme (UNEP) pilot study to assess environmentally-sound and cost-effective LLIN recycling strategies, the USAID-Deliver Project collected 22,559 used bed nets in Madagascar. A social science study was conducted to provide data on socio-cultural factors related to collection and replacement of LLINs, including impact on primary and other net uses. Ethnographic exploratory research was carried out following the pilot USAID-Deliver net collection and recycling campaign in Betioky, Tsihombe, Fenerive Est and Ambanja districts of Madagascar, triangulating participant observation, interviewing and group discussions. Sampling was theoretical and data analysis was a continuous and iterative process concurrent to data collection. Final analysis was conducted using NVivo10. The following themes emerged as contributing to the success of collecting expired LLINs in the community for recycling purposes: (i) net adequacy and preference: characteristic differences between collected and newly distributed nets lead to communities' reticence to relinquish old nets before confirming new nets were appropriate for intended use. Where newly distributed nets failed to meet local requirements, this was expected to increase alternative uses and decrease household turn over. (ii) Net collection strategies: the net collection campaign brought net use out of the private