Science.gov

Sample records for persistent water level

  1. Persistent water level changes in a well near Parkfield, California, due to local and distant earthquakes

    NASA Astrophysics Data System (ADS)

    Roeloffs, Evelyn A.

    1998-01-01

    Coseismic water level rises in the 30-m deep Bourdieu Valley (BV) well near Parkfield, California, have occurred in response to three local and five distant earthquakes. Coseismic changes in static strain cannot explain these water level rises because (1) the well is insensitive to strain at tidal periods; (2) for the distant earthquakes, the expected coseismic static strain is extremely small; and (3) the water level response is of the incorrect sign for the local earthquakes. These water level changes must therefore be caused by seismic waves, but unlike seismic water level oscillations, they are monotonic, persist for days or weeks, and seem to be caused by waves with periods of several seconds rather than long-period surface waves. Other investigators have reported a similar phenomenon in Japan. Certain wells consistently exhibit this type of coseismic water level change, which is always in the same direction, regardless of the earthquake's azimuth or focal mechanism, and approximately proportional to the inverse square of hypocentral distance. To date, the coseismic water level rises in the B V well have never exceeded the seasonal water level maximum, although their sizes are relatively well correlated with earthquake magnitude and distance. The frequency independence of the well's response to barometric pressure in the frequency band 0.1 to 0.7 cpd implies that the aquifer is fairly well confined. High aquifer compressibility, probably due to a gas phase in the pore space, is the most likely reason why the well does not respond to Earth tides. The phase and amplitude relationships between the seasonal water level and precipitation cycles constrain the horizontal hydraulic diffusivity to within a factor of 4.5, bounding hypothetical earthquake-induced changes in aquifer hydraulic properties. Moreover, changes of hydraulic conductivity and/or diffusivity throughout the aquifer would not be expected to change the water level in the same direction at every time

  2. Persistent water level changes in a well near Parkfield, California, due to local and distant earthquakes

    USGS Publications Warehouse

    Roeloffs, E.A.

    1998-01-01

    Coseismic water level rises in the 30-m deep Bourdieu Valley (BV) well near Parkfield, California, have occurred in response to three local and five distant earthquakes. Coseismic changes in static strain cannot explain these water level rises because (1) the well is insensitive to strain at tidal periods; (2) for the distant earthquakes, the expected coseismic static strain is extremely small; and (3) the water level response is of the incorrect sign for the local earthquakes. These water level changes must therefore be caused by seismic waves, but unlike seismic water level oscillations, they are monotonic, persist for days or weeks, and seem to be caused by waves with periods of several seconds rather than long-period surface waves. Other investigators have reported a similar phenomenon in Japan. Certain wells consistently exhibit this type of coseismic water level change, which is always in the same direction, regardless of the earthquake's azimuth or focal mechanism, and approximately proportional to the inverse square of hypocentral distance. To date, the coseismic water level rises in the BV well have never exceeded the seasonal water level maximum, although their sizes are relatively well correlated with earthquake magnitude and distance. The frequency independence of the well's response to barometric pressure in the frequency band 0.1 to 0.7 cpd implies that the aquifer is fairly well confined. High aquifer compressibility, probably due to a gas phase in the pore space, is the most likely reason why the well does not respond to Earth tides. The phase and amplitude relationships between the seasonal water level and precipitation cycles constrain the horizontal hydraulic diffusivity to within a factor of 4.5, bounding hypothetical earthquake-induced changes in aquifer hydraulic properties. Moreover, changes of hydraulic conductivity and/or diffusivity throughout the aquifer would not be expected to change the water level in the same direction at every time

  3. Derivation of a drinking water equivalent level (DWEL) related to the maximum contaminant level goal for perfluorooctanoic acid (PFOA), a persistent water soluble compound.

    PubMed

    Tardiff, Robert G; Carson, M Leigh; Sweeney, Lisa M; Kirman, Christopher R; Tan, Yu-Mei; Andersen, Melvin; Bevan, Christopher; Gargas, Michael L

    2009-10-01

    Water soluble compounds persistent in humans and the environment pose a challenge for estimating safe levels in tap water. A viable approach to estimate a drinking water equivalent level (DWEL) for perfluorooctanoic acid (PFOA) was applied to its extensive relevant information from human and laboratory animal studies. PFOA has been identified at 3.5 microg/L (mean) in tap water in proximity to a manufacturing facility; however, in most supplies, the levels were below 7.5 ng/L (usual limit of detection). PFOA has an average half-life in humans of 3.5years. From animal studies, PFOA is considered a possible hepatotoxicant and developmental toxicant for humans. Based on two chronic studies, PFOA was judged to be a possible human carcinogen, whose mode-of-action was likely to be related to receptor activation but not genotoxicity. The Benchmark Dose-Uncertainty Factor approach was selected for dose-response for noncancer and cancer. Based on internal dose of PFOA, the DWEL protective against cancer is 7.7 microgPFOA/L tap water, and the noncancer DWELs range from 0.88 to 2.4 microg/L. These DWELs can be considered a reliable, albeit conservative, basis to set a Maximum Concentration Level Goal under the US Safe Drinking Water Act. PMID:19631249

  4. Occurrence and persistence of water level/salinity states and the ecological impacts for St Lucia estuarine lake, South Africa

    NASA Astrophysics Data System (ADS)

    Lawrie, Robynne A.; Stretch, Derek D.

    2011-11-01

    The St Lucia estuarine lake in South Africa forms part of a World Heritage Site and is an important local source of biodiversity. Like many estuarine systems worldwide, St Lucia has experienced significant anthropogenic impacts over the past century. Abstractions have decreased fresh water inflows from the lake catchments by about 20%. Furthermore the Mfolozi river, which previously shared a common inlet with St Lucia and contributed additional fresh water during droughts, was diverted from the system in 1952 because of its high silt loads. The separated St Lucia mouth was subsequently kept artificially open until the onset of a dry period in 2002 when the mouth was left to close naturally. These changes and the current drought have placed the system under severe stress with unprecedented hypersaline conditions coupled with desiccation of large portions of the lake. Long-term simulations of the water and salt balance were used to estimate the occurrence and persistence of water levels and salinities for different management scenarios. The risks of desiccation and hyper-salinity were assessed for each case. The results show that the configuration of the Mfolozi/St Lucia inlets plays a key role in the physicochemical environment of the system. Without the Mfolozi link desiccation (of about 50% of the lake area) would occur for 32% of the time for an average duration of 15 months. Artificially maintaining an open mouth would decrease the chance of desiccation but salinities would exceed 65 about 17% of the time. Restoring the Mfolozi link would reduce the occurrence of both desiccation and hypersaline conditions and a mostly open mouth state would occur naturally. Integrating these modeled scenarios with observed biological responses due to changes in salinity and water depth suggests that large long-term changes in the biological structure can be expected in the different management scenarios.

  5. Effect of repeated irrigation with water containing varying levels of total organic carbon on the persistence of Escherichia coli O157:H7 on baby spinach.

    PubMed

    Ingram, David T; Patel, Jitu; Sharma, Manan

    2011-05-01

    The California lettuce and leafy greens industry has adopted the Leafy Greens Marketing Agreement (LGMA), which allows for 126 most-probable-number (MPN) Escherichia coli per 100 ml in irrigation water. Repeat irrigation of baby spinach plants with water containing E. coli O157:H7 and different levels of total organic carbon (TOC) was used to determine the epiphytic survival of E. coli O157:H7. Three irrigation treatments (0 ppm of TOC, 12 or 15 ppm of TOC, and 120 or 150 ppm of TOC) were prepared with bovine manure containing E. coli O157:H7 at either low (0 to 1 log CFU/100 ml) or high (5 to 6 log CFU/100 ml) populations, and sprayed onto baby spinach plants in growth chambers by using a fine-mist airbrush. MPN and direct plating techniques were used to determine the E. coli O157:H7 populations on the aerial plant tissue. Plants irrigated with high E. coli O157:H7 populations, regardless of TOC levels, showed a 3-log reduction within the first 24 h. Low levels of E. coli O157:H7 were observed for up to 16 days on all TOC treatments, ranging from 76.4 MPN per plant (day 1) to 0.40 MPN per plant (day 16). No viable cells were detected on spinach tissue 24 h after irrigation with water containing fewer than 126 CFU/100 ml E. coli O157:H7. Under growth chamber conditions in this study, E. coli O157:H7 populations in irrigation water that complies with the LGMA standards will not persist for more than 24 h when applied onto foliar surfaces of spinach plants.

  6. Persisting water droplets on water surfaces.

    PubMed

    Klyuzhin, Ivan S; Ienna, Federico; Roeder, Brandon; Wexler, Adam; Pollack, Gerald H

    2010-11-11

    Droplets of various liquids may float on the respective surfaces for extended periods of time prior to coalescence. We explored the features of delayed coalescence in highly purified water. Droplets several millimeters in diameter were released from a nozzle onto a water surface. Results showed that droplets had float times up to hundreds of milliseconds. When the droplets did coalesce, they did so in stepwise fashion, with periods of quiescence interspersed between periods of coalescence. Up to six steps were noted before the droplet finally vanished. Droplets were released in a series, which allowed the detection of unexpected abrupt float-time changes throughout the duration of the series. Factors such as electrostatic charge, droplet size, and sideways motion had considerable effect on droplet lifetime, as did reduction of pressure, which also diminished the number of steps needed for coalescence. On the basis of present observations and recent reports, a possible mechanism for noncoalescence is considered. PMID:20961076

  7. The Effect of Repeated Irrigation with Water Containing Varying Levels of Total Organic Carbon on the Persistence of Escherichia coli O157:H7 on Baby Spinach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The California lettuce and leafy greens industry has adopted the Leafy Greens Marketing Agreement (LGMA), which allows for 126 Most Probable Number (MPN) generic E. coli/100ml in irrigation water. Repeat irrigation of baby spinach plants with water containing E. coli O157:H7 and different levels of...

  8. Misconceptions in Optics: Their Persistence at University Level.

    ERIC Educational Resources Information Center

    Gil Llinas, J.; Suero Lopez, M. I.; Perez Rodriguez, A. L.; Solano Macias, F.

    2003-01-01

    Presents a study on misconceptions in optics with the objective of checking their persistence over time in spite of the continued academic instruction of students. Involves (n=4000) students of all levels of the Spanish educational system as well as with those at a Spanish university with degrees in medicine, chemical sciences, technical…

  9. Persistence of selected organophosphate and carbamate insecticides in waters from a coastal watershed.

    PubMed

    Bondarenko, Svetlana; Gan, Jianying; Haver, Darren L; Kabashima, John N

    2004-11-01

    Organophosphate and carbamate compounds are among the most widely used pesticides. Contamination of surface water by these compounds is of concern because of potential toxicity to aquatic organisms, especially those at lower trophic levels. In this study we evaluated the persistence of diazinon, chlorpyrifos, malathion, and carbaryl in waters from various sites in the Newport Bay-San Diego Creek watershed in southern California (USA). The persistence of diazinon and chlorpyrifos was much longer than that of malathion or carbaryl and was further prolonged in seawater. Microbial degradation contributed significantly to the dissipation of diazinon and chlorpyrifos in freshwater, but was inhibited in seawater, leading to increased persistence. In contrast, degradation of malathion and carbaryl was rapid and primarily abiotic. A greater temperature dependence was observed for carbaryl degradation in all waters and for diazinon degradation in freshwater. The interactions of pesticide persistence with water location, temperature, and type of pesticides suggest that site- and compound-specific information is needed when evaluating the overall ecotoxicological risks of pesticide pollution in a watershed. Because the persistence of diazinon and chlorpyrifos may increase significantly in seawater, mitigation should occur before the pesticides reach seawater. The relatively short persistence of these compounds in freshwater suggests that practices aimed at extending residence time (e.g., diversion to wetlands) may effectively reduce pesticide output to downstream water bodies.

  10. Dichlorobenzene in ground water: Evidence for long-term persistence

    USGS Publications Warehouse

    Barber, L.B.

    1988-01-01

    Hydrologic and geochemical evidence were used to establish the long-term persistence of dichlorobenzene in ground water that has been contaminated from 50 years of rapid-infiltration sewage disposal. An extensive plume of dichlorobenzene extends more than 3,500 meters downgradient from the disposal beds, with concentrations of the combined isomers ranging from less than 0.01 to over 1.0 ??g/l. Based on estimates of maximum ground-water flow velocities, a minimum age of 20 years was established for the farthest downgradient zone of dichlorobenzene contamination. Branched-chained, alkylbenzenesulfonic acid surfactants, that were introduced into the ground water prior to 1966, occur along with dichlorobenzene in the downgradient part of the plume, further establish residence of the compounds in the aquifer for at least 20 years. Although dichlorobenzene can be biologically degraded under aerobic conditions, its persistence at this field site is attributed to the dynamics of the ground-water system. Denitrifying conditions, resulting from the degradation of organic compounds in the aquifer near the disposal beds, appear to have enhanced the persistence of dichlorobenzene, which is not degraded by anaerobic bacteria. Biological degradation of dichlorobenzene in the aerobic part of the plume downgradient from the source is probably limited by the paucity of a suitable organic-carbon substrate and the low concentrations of dissolved oxygen in the contaminated ground water.

  11. Fibre persistence on immersed garment - Influence of water flow and stay in running water.

    PubMed

    Lepot, L; Vanden Driessche, T

    2015-12-01

    The persistence of fibre traces is a critical factor in the evaluation of fibre findings in forensic casework. Water can play a major role in affecting fibre persistence as a lot of fibre traces can get lost after washing incriminated garments, after rainfall over the victim's body or after immersion of the victim in water. The influence of immersion in standing water on fibre persistence was previously studied in our laboratory on various knitted recipient fabrics. The present study is focused on the persistence of target fibres on immersed cotton T-shirts through an immersion/stay/emersion process in running water (from 1h up to 7h), simulated in laboratory (~0.4l/s, gentle water flow conditions) and in real conditions (~2000l/s, medium water flow conditions). A gentle water flow slightly affects fibre persistence, which remains more or less constant over time, regardless of the duration of the stay in water. No rapid loss is observed during immersion in real conditions, including a medium water flow and boat activity. The fibre persistence in running water seems to depend mainly on the immersion step and also, in case of a medium water flow, on the stay in water with a linear loss over hours. PMID:26654078

  12. Vegetation persistence and carbon storage: Implications for environmental water management for Phragmites australis

    NASA Astrophysics Data System (ADS)

    Whitaker, Kai; Rogers, Kerrylee; Saintilan, Neil; Mazumder, Debashish; Wen, Li; Morrison, R. J.

    2015-07-01

    Environmental water allocations are used to improve the ecological health of wetlands. There is now increasing demand for allocations to improve ecosystem productivity and respiration, and enhance carbon sequestration. Despite global recognition of wetlands as carbon sinks, information regarding carbon dynamics is lacking. This is the first study estimating carbon sequestration for semiarid Phragmites australis reedbeds. The study combined aboveground biomass assessments with stable isotope analyses of soils and modeling of biomass using Normalized Digital Vegetation Index (NDVI) to investigate the capacity of environmental water allocations to improve carbon storage. The study considered relationships between soil organic carbon (SOC), carbon sources, and reedbed persistence in the Macquarie Marshes, a regulated semiarid floodplain of the Murray-Darling Basin, Australia. SOC storage levels to 1 m soil depth were higher in persistent reedbeds (167 Mg ha-1) than ephemeral reedbeds (116-138 Mg ha-1). In situ P. australis was the predominant source of surface SOC at persistent reedbeds; mixed sources of surface SOC were proposed for ephemeral reedbeds. 13C enrichment with increasing soil depth occurred in persistent and ephemeral reedbeds and may not relate to flow characteristics. Despite high SOC at persistent reedbeds, differences in the rate of accretion contributed to significantly higher rates of carbon sequestration at ephemeral reedbeds (approximately 554 and 465 g m-2 yr-1) compared to persistent reedbeds (5.17 g m-2 yr-1). However, under current water regimes, rapid accretion at ephemeral reedbeds cannot be maintained. Effective management of persistent P. australis reedbeds may enhance carbon sequestration in the Macquarie Marshes and floodplain wetlands more generally.

  13. Persistence of Helicobacter pylori in heterotrophic drinking-water biofilms.

    PubMed

    Gião, M S; Azevedo, N F; Wilks, S A; Vieira, M J; Keevil, C W

    2008-10-01

    Although the route of transmission of Helicobacter pylori remains unknown, drinking water has been considered a possible transmission vector. It has been shown previously that, in water, biofilms are a protective niche for several pathogens, protecting them from stressful conditions, such as low carbon concentration, shear stress, and less-than-optimal temperatures. In this work, the influence of these three parameters on the persistence and cultivability of H. pylori in drinking-water biofilms was studied. Autochthonous biofilm consortia were formed in a two-stage chemostat system and then inoculated with the pathogen. Total numbers of H. pylori cells were determined by microscopy using a specific H. pylori 16S rRNA peptide nucleic acid probe, whereas cultivable cells were assessed by standard plating onto selective H. pylori medium. Cultivable H. pylori could not be detected at any time point, but the ability of H. pylori cells to incorporate, undergo morphological transformations, persist, and even agglomerate in biofilms for at least 31 days without a noticeable decrease in the total cell number (on average, the concentration was between 1.54 x 10(6) and 2.25 x 10(6) cells cm(-2)) or in the intracellular rRNA content may indicate that the loss of cultivability was due to entry into a viable but noncultivable state. Unlike previous results obtained for pure-culture H. pylori biofilms, shear stress did not negatively influence the numbers of H. pylori cells attached, suggesting that the autochthonous aquatic bacteria have an important role in retaining this pathogen in the sessile state, possibly by providing suitable microaerophilic environments or linking biomolecules to which the pathogen adheres. Therefore, biofilms appear to provide not only a safe haven for H. pylori but also a concentration mechanism so that subsequent sloughing releases a concentrated bolus of cells that might be infectious and that could escape routine grab sample microbiological

  14. Hydrogeology and water quality of areas with persistent ground- water contamination near Blackfoot, Bingham County, Idaho

    USGS Publications Warehouse

    Parliman, D.J.

    1987-01-01

    The Groveland-Collins area near Blackfoot, Idaho, has a history of either periodic or persistent localized groundwater contamination. Water users in the area report offensive smell, metallic taste, rust deposits, and bacteria in water supplies. During 1984 and 1985, data were collected to define regional and local geologic, hydrologic, and groundwater quality conditions, and to identify factors that may have affected local groundwater quality. Infiltration or leakage of irrigation water is the major source of groundwater recharge, and water levels may fluctuate 15 ft or more during the irrigation season. Groundwater movement is generally northwestward. Groundwater contains predominantly calcium, magnesium, and bicarbonate ions and characteristically has more than 200 mg/L hardness. Groundwater near the Groveland-Collins area may be contaminated from one or more sources, including infiltration of sewage effluent, gasoline or liquid fertilizer spillage, or land application of food processing wastewater. Subsurface basalt ridges impede lateral movement of water in localized areas. Groundwater pools temporarily behind these ridges and anomalously high water levels result. Maximum concentrations or values of constituents that indicate contamination were 1,450 microsiemens/cm specific conductance, 630 mg/L bicarbonate (as HCO3), 11 mg/L nitrite plus nitrate (as nitrogen), 7.3 mg/L ammonia (as nitrogen), 5.9 mg/L organic nitrogen, 4.4 mg/L dissolved organic carbon, 7,000 micrograms/L dissolved iron, 5 ,100 microgram/L dissolved manganese, and 320 microgram/L dissolved zinc. Dissolved oxygen concentrations ranged from 8.9 mg/L in uncontaminated areas to 0 mg/L in areas where food processing wastewater is applied to the land surface. Stable-isotope may be useful in differentiating between contamination from potato-processing wastewater and whey in areas where both are applied to the land surface. Development of a ground-water model to evaluate effects of land applications

  15. Increasing levels and biomagnification of persistent organic pollutants (POPs) in Antarctic biota.

    PubMed

    Goerke, Helmut; Weber, Kurt; Bornemann, Horst; Ramdohr, Sven; Plötz, Joachim

    2004-02-01

    Representatives of the Antarctic food web (krill, cephalopod, fish, penguin, seal) of the area around Elephant Island and from the Weddell Sea were analysed for the most recalcitrant organochlorine compounds. Due to sorption of the compounds to sinking particles and accumulation in sediments, two benthic fish species (Gobionotothen gibberifrons, Chaenocephalus aceratus) feeding on benthos invertebrates and fish reflected significantly increasing concentrations within a decade (1987-1996), while a benthopelagic species (Champsocephalus gunnari) feeding on krill did not. In the pelagic food chain, lipid normalised concentrations of all compounds increased from Antarctic krill to fish proving that biomagnification of highly lipophilic pollutants (log octanol-water partition coefficient>5) occurs in water-breathing animals. As top predators Weddell and southern elephant seals (Leptonychotes weddellii, Mirounga leonina) biomagnified the persistent organic pollutants relative to krill 30-160 fold with the exception of hexachlorobenzene, the levels of which were lower than in fish indicating its intense specific elimination.

  16. Arsenic levels in Oregon waters.

    PubMed

    Stoner, J C; Whanger, P D; Weswig, P H

    1977-08-01

    The arsenic content of well water in certain areas of Oregon can range up to 30 to 40 times the U.S.P.H.S. Drinking Water Standard of 1962, where concentrations in excess of 50 ppb are grounds for rejection. The elevated arsenic levels in water are postulated to be due to volcanic deposits. Wells in central Lane County, Oregon, that are known to contain arsenic rich water are in an area underlain by a particular group of sedimentary and volcanic rocks, which geologists have named the Fischer formation. The arsenic levels in water from wells ranged from no detectable amounts to 2,000 ppb. In general the deeper wells contained higher arsenic water. The high arsenic waters are characterized by the small amounts of calcium and magnesium in relation to that of sodium, a high content of boron, and a high pH. Water from some hot springs in other areas of Oregon was found to range as high as 900 ppb arsenic. Arsenic blood levels ranged from 32 ppb for people living in areas where water is low in arsenic to 250 ppb for those living in areas where water is known to contain high levels of arsenic. Some health problems associated with consumption of arsenic-rich water are discussed.

  17. Relationships between Human Water Use, Groundwater Persistence and Baseflow Contribution in New Jersey

    NASA Astrophysics Data System (ADS)

    Thomas, B.; Vogel, R. M.; Kanwar, P.; Hoover, J. H.; Arrigo, J. S.

    2010-12-01

    Groundwater is a vital resource throughout the Northeast corridor and is an important water resource for domestic, industrial, and irrigation purposes. During the 20th century, groundwater withdrawals intensified to meet water demands, especially suburban areas. This increased water demand is documented by the U.S. Geological Survey National Water-Use Information Program. Analysis of detailed county water usage from 1985 to 2005 indicated increased groundwater withdrawals across many suburban areas, including much of New Jersey. The primary goal of this study is to link changes in the behavior of groundwater systems with observed changes in conjunctive water use. We document changes in groundwater level trends which are likely due to groundwater/surface water interactions impacted by human interaction with the hydrologic system. Measures of groundwater persistence are employed to quantify the behavior of groundwater systems. Persistence refers to the dependence of successive records in a time series which is a property of hydrologic systems and is hypothesized to change in response to changes in human water use. Lag-one serial correlations of available groundwater records between 1920 and 2000 are computed to test the hypothesis in the groundwater system. We also compute the daily baseflow index, or the fraction of total streamflow which arises from baseflow, to detect changes in baseflow contribution to streamflow which result from withdrawal-dominated groundwater systems. Finally, we report relationships between changes in both the baseflow index and lag-one serial correlation of groundwater levels and associated changes in human water use in New Jersey.

  18. Strain-related variation in the persistence of influenza A virus in three types of water: distilled water, filtered surface water, and intact surface water

    PubMed Central

    2013-01-01

    Background The persistence of influenza A (IA) virus in aquatic habitats has been demonstrated to be a determinant for virus transmission dynamics in wild duck populations. In this study, we investigated virus strain-related variation in persistence in water for nine wild duck isolated IA viruses of three subtypes (H3N8, H4N6, and H8N4). Results We experimentally estimated the loss of infectivity over time in three different types of water: distilled, filtered surface water, and intact surface water. All viruses persisted longest in distilled water followed by filtered surface water with markedly reduced durations of persistence observed in the intact surface water. Strain-related variations were observed in distilled and filtered surface water but limited variation was observed in the intact surface water. Conclusions Our findings suggest that the role of surface water for long-term (between years) maintenance of AI viruses in the environment may be limited, and suggest that the physico-chemical characteristics of water, as well as microorganisms, may be of strong importance. Results also indicate that the extent of strain-related variation observed in distilled water may overestimate persistence abilities for IA viruses in the wild and supports the need to develop experiments that account for these effects to assess subtype, genotype, as well as spatial and temporal variation in the persistence of IA viruses in aquatic habitats. PMID:23289857

  19. Water Resources System Archetypes: Towards a Holistic Understanding of Persistent Water Resources Problems

    NASA Astrophysics Data System (ADS)

    Mirchi, A.; Watkins, D. W.; Madani, K.

    2011-12-01

    Water resources modeling, a well-established tool in water resources planning and management practice, facilitates understanding of the physical and socio-economic processes impacting the wellbeing of humans and ecosystems. While watershed models continue to become more holistic, there is a need for appropriate frameworks and tools for integrated conceptualization of problems to provide reliable qualitative and quantitative bases for policy selection. In recent decades, water resources professionals have become increasingly cognizant of important feedback relationships within water resources systems. We contend that a systems thinking paradigm is required to facilitate characterization of the closed-loop nature of these feedbacks. Furthermore, a close look at different water resources issues reveals that, while many water resources problems are essentially very similar in nature, they continuously appear in different geographical locations. In the systems thinking literature, a number of generic system structures known as system archetypes have been identified to describe common patterns of problematic behavior within systems. In this research, we identify some main system archetypes governing water resources systems, demonstrating their benefits for holistic understanding of various classes of persistent water resources problems. Using the eutrophication problem of Lake Allegan, Michigan, as a case study, we illustrate how the diagnostic tools of system dynamics modeling can facilitate identification of problematic feedbacks within water resources systems and provide insights for sustainable development.

  20. The Politics of Pipes: The Persistence of Small Water Networks in Post-Privatization Manila

    NASA Astrophysics Data System (ADS)

    Cheng, Deborah

    -network consumers are subject to disparities in cost, materials, and personal freedoms. Though Manila's water privatization project has resulted in significant improvements to the centralized system, its success must be tempered by the inequalities that remain. Second, the two utilities are largely able to shape both the geographies of water access and the production of knowledge. For this reason, the utilities typically use micro-networks where cost recovery may be difficult---such as in areas with uncertain land tenure or where higher levels of nonpayment are perceived---while including these areas in their aggregate coverage statistics. Third, the presence of multiple providers of water and other basic services blurs the boundaries between public, private, and community. But that blurriness serves to consolidate the private utilities' power, while increasing the opacity by which citizens navigate processes related to urban water provision. The persistence of micro-networks thus allows us to understand the ways in which low-income spaces are made more governable. By focusing on this peri-urban frontier, this project asserts that differentiation and discipline serve simultaneously as tools of governance and as points of contestation. What emerges is a waterscape consisting not of one type of privatization---where service and access are uniformly provided---but multiple, coexisting, and differentiated privatizations.

  1. Abiotic Factors Affecting the Persistence of Avian Influenza Virus in Surface Waters of Waterfowl Habitats

    PubMed Central

    Dalton, Melinda S.; Cressler, Alan M.; Berghaus, Roy D.; Stallknecht, David E.

    2014-01-01

    Avian influenza (AI) virus can remain infectious in water for months, and virus-contaminated surface water is considered to be a source of infection within wild waterfowl populations. Previous work has characterized the effects of pH, salinity, and temperature on viral persistence in water, but most of that work was done with modified distilled water. The objective of this study was to identify the abiotic factors that influence the duration of AI virus persistence in natural surface water. Surface water samples were collected from 38 waterfowl habitats distributed across the United States. Samples were submitted to the U.S. Geological Survey National Water Quality Laboratory for chemical analysis and the University of Georgia for viral reduction time analysis. Samples were filtered with 0.22-μm filters, and the durations of persistence of three wild-bird-derived influenza A viruses within each water sample at 10, 17, and 28°C were determined. The effects of the surface water physicochemical factors on the duration of AI viral persistence in laboratory experiments were evaluated by multivariable linear regression with robust standard errors. The duration of AI virus persistence was determined to be longest in filtered surface water with a low temperature (<17°C), a neutral-to-basic pH (7.0 to 8.5), low salinity (<0.5 ppt), and a low ammonia concentration (<0.5 mg/liter). Our results also highlighted potential strain-related variation in the stability of AI virus in surface water. These results bring us closer to being able to predict the duration of AI virus persistence in surface water of waterfowl habitats. PMID:24584247

  2. Effect of Learning Activity on Students' Motivation, Physical Activity Levels and Effort/Persistence

    ERIC Educational Resources Information Center

    Gao, Zan; Lee, Amelia M.; Xiang, Ping; Kosma, Maria

    2011-01-01

    The type of learning activity offered in physical education may influence students' motivational beliefs, physical activity participation and effort/persistence in class. However, most empirical studies have focused on the individual level rather than on the learner-content interactions. Accordingly, the potential effects of learning activities on…

  3. The Persistence of Misconceptions about the Human Blood Circulatory System among Students in Different Grade Levels

    ERIC Educational Resources Information Center

    Ozgur, Sami

    2013-01-01

    In this paper, it is aimed to investigate the persistence of misconceptions in the topic of the human blood circulatory system among students in different grade levels. For this reason, after discussions with biology educators, two tests consisting of open-ended questions were developed by the researcher and administered to students in four…

  4. Infectivity and genome persistence of rotavirus and astrovirus in groundwater and surface water.

    PubMed

    Espinosa, Ana Cecilia; Mazari-Hiriart, Marisa; Espinosa, Rafaela; Maruri-Avidal, Liliana; Méndez, Ernesto; Arias, Carlos F

    2008-05-01

    In this work, we have characterized the survival of Rhesus rotavirus (RRV) and human astrovirus Yuc8 in clean groundwater and contaminated surface water, as well as in phosphate-buffered solutions maintained in the same conditions as the environmental waters, and have compared the dynamics of virus inactivation with the persistence of the viral genomes, as determined by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). In addition, we also studied the tolerance of these viruses to chlorine disinfection. The reduction of infectivity of astrovirus was higher than for rotavirus, and also higher for both viruses in surface water as compared to groundwater. The enterobacterial content of the water as well as extrinsic factors, such as temperature and light, correlated with the stability of virus infectivity, and with the persistence of the virus genetic material, suggesting that molecular techniques to detect and quantify viral genomes would be suitable for the detection of viruses in water. The virus infectivity persisted in both types of water as well as in chlorine for times longer than previously reported. No decrease of infectivity was observed after 15 days of incubation in either type of water and the viruses remained infectious for months in groundwater. After 120 min in groundwater containing 2 mg/L of free chlorine, the infectivity of rotavirus and astrovirus was reduced by 0.78 and 1.3 logs, respectively. The longer persistence of viruses in this study could result from a combination of factors, including aggregation of the virus.

  5. Viral persistence in surface and drinking water: Suitability of PCR pre-treatment with intercalating dyes.

    PubMed

    Prevost, B; Goulet, M; Lucas, F S; Joyeux, M; Moulin, L; Wurtzer, S

    2016-03-15

    After many outbreaks of enteric virus associated with consumption of drinking water, the study of enteric viruses in water has increased significantly in recent years. In order to better understand the dynamics of enteric viruses in environmental water and the associated viral risk, it is necessary to estimate viral persistence in different conditions. In this study, two representative models of human enteric viruses, adenovirus 41 (AdV 41) and coxsackievirus B2 (CV-B2), were used to evaluate the persistence of enteric viruses in environmental water. The persistence of infectious particles, encapsidated genomes and free nucleic acids of AdV 41 and CV-B2 was evaluated in drinking water and surface water at different temperatures (4 °C, 20 °C and 37 °C). The infectivity of AdV 41 and CV-B2 persisted for at least 25 days, whatever the water temperature, and for more than 70 days at 4 °C and 20 °C, in both drinking and surface water. Encapsidated genomes persisted beyond 70 days, whatever the water temperature. Free nucleic acids (i.e. without capsid) also were able to persist for at least 16 days in drinking and surface water. The usefulness of a detection method based on an intercalating dye pre-treatment, which specifically targets preserved particles, was investigated for the discrimination of free and encapsidated genomes and it was compared to virus infectivity. Further, the resistance of AdV 41 and CV-B2 against two major disinfection treatments applied in drinking water plants (UV and chlorination) was evaluated. Even after the application of UV rays and chlorine at high doses (400 mJ/cm(2) and 10 mg.min/L, respectively), viral genomes were still detected with molecular biology methods. Although the intercalating dye pre-treatment had little use for the detection of the effects of UV treatment, it was useful in the case of treatment by chlorination and less than 1 log10 difference in the results was found as compared to the infectivity measurements

  6. Halogenated persistent organic pollutants in deep water fish from waters to the west of Scotland.

    PubMed

    Webster, Lynda; Walsham, Pam; Russell, Marie; Hussy, Ines; Neat, Francis; Dalgarno, Eric; Packer, Gill; Scurfield, Judith A; Moffat, Colin F

    2011-04-01

    Halogenated persistent organic pollutants [polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs)] along with total lipid, were measured in the liver and muscle of three species of deep water fish (black scabbard, black dogfish (liver only) and roundnose grenadier) collected from the Rockall fishing area, to the west of Scotland, between 2006 and 2008. Both contaminant groups were detected in the muscle and liver, with concentrations of PCBs being higher than PBDEs. There were no significant differences in the PCB or PBDE concentrations between the three species, or different sampling locations in the Rockall fishing area. PCB concentrations (ΣICES (International Council for the Exploration of the Sea)7 PCBs) greater than 500 μg kg(-1) lipid weight were found in 26 of the 106 liver samples. PCB concentrations were compared to OSPAR assessment criteria, concentrations were above background but below Environmental Assessment Criteria. Estimated Toxic Equivalent (TEQ) concentrations, calculated using published models, in the fish muscle and liver indicated that consumption of deep water fish is unlikely to represent a risk to human health. The high squalene content in some of the black dogfish liver necessitated an additional clean-up step, involving gel permeation chromatography, when analyzing for PBDEs. Concentrations of PBDEs were low with many congeners being below detection limits, particularly in the muscle. There are currently no assessment criteria available for PBDEs. Furthermore, there is only very limited data on PBDEs in deep water fish. However, the concentrations observed in this study were similar to the concentrations recently reported in Mediterranean deep water fish. PMID:21421255

  7. Halogenated persistent organic pollutants in deep water fish from waters to the west of Scotland.

    PubMed

    Webster, Lynda; Walsham, Pam; Russell, Marie; Hussy, Ines; Neat, Francis; Dalgarno, Eric; Packer, Gill; Scurfield, Judith A; Moffat, Colin F

    2011-04-01

    Halogenated persistent organic pollutants [polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs)] along with total lipid, were measured in the liver and muscle of three species of deep water fish (black scabbard, black dogfish (liver only) and roundnose grenadier) collected from the Rockall fishing area, to the west of Scotland, between 2006 and 2008. Both contaminant groups were detected in the muscle and liver, with concentrations of PCBs being higher than PBDEs. There were no significant differences in the PCB or PBDE concentrations between the three species, or different sampling locations in the Rockall fishing area. PCB concentrations (ΣICES (International Council for the Exploration of the Sea)7 PCBs) greater than 500 μg kg(-1) lipid weight were found in 26 of the 106 liver samples. PCB concentrations were compared to OSPAR assessment criteria, concentrations were above background but below Environmental Assessment Criteria. Estimated Toxic Equivalent (TEQ) concentrations, calculated using published models, in the fish muscle and liver indicated that consumption of deep water fish is unlikely to represent a risk to human health. The high squalene content in some of the black dogfish liver necessitated an additional clean-up step, involving gel permeation chromatography, when analyzing for PBDEs. Concentrations of PBDEs were low with many congeners being below detection limits, particularly in the muscle. There are currently no assessment criteria available for PBDEs. Furthermore, there is only very limited data on PBDEs in deep water fish. However, the concentrations observed in this study were similar to the concentrations recently reported in Mediterranean deep water fish.

  8. Persistent organic pollutants and anti-thyroid peroxidase levels in Akwesasne Mohawk young adults

    PubMed Central

    Schell, Lawrence M.; Gallo, Mia V.; Ravenscroft, Julia; DeCaprio, Anthony P.

    2009-01-01

    Persistent organic pollutants, such as PCBs, HCB and DDE, have been found to elicit a broad spectrum of biologic, metabolic, and immunologic responses. The potential of these pollutants to impair immune responses and trigger autoimmune disease is of growing concern, given their structural similarity to thyroid hormones and their potential to modulate the mechanisms and interfere with the binding of these hormones. We examine the relationship of different groupings of PCBs, according to chlorination and structure, and of p,p’-DDE and HCB to anti-thyroid peroxidase antibody, a useful tool in the evaluation of thyroid dysfunction, among 115 young adults of the Akwesasne Mohawk Nation. Overall, eighteen participants (15.4%) had TPOAb levels above the normal laboratory reference range (23% of females, 9% of males). Among participants who were breast fed (n=47), those with an elevated TPOAb level had significantly higher levels of all PCB groupings, with the exception of levels of non-persistent PCBs which did not differ significantly. Levels of p,p’-DDE were also significantly elevated, while HCB and mirex were not higher among those with elevated TPOAb. Also, after stratifying by breast feeding status, participants who were breast fed showed significant, positive relationships between TPOAb levels and all PCB groupings, except groups comprised of non-persistent PCBs, and with p,p’-DDE, HCB, and mirex. No effects were evident among non-breastfed young adults. Further studies are necessary to elucidate the site and mechanism of action of these POPs and to establish thresholds for these effects, especially among populations with background levels of toxicant exposure. PMID:18995849

  9. Organic persistent toxic substances in soils, waters and sediments along an altitudinal gradient at Mt. Sagarmatha, Himalayas, Nepal.

    PubMed

    Guzzella, Licia; Poma, Giulia; De Paolis, Adolfo; Roscioli, Claudio; Viviano, Gaetano

    2011-10-01

    Persistent Organic Pollutants (POPs) and Polycyclic Aromatic Hydrocarbons (PAHs) are important classes of compounds of serious environmental concern. These compounds were measured in waters, sediments and soils from several high altitude sites in the Sagarmatha National Park (Nepal) and included in the Himalayan ridge. In water samples, low-level substituted PCBs and PBDEs, along with more volatile PAHs, were the most common contaminants. In sediment and soil samples, the PCB profile was mainly composed of medium-level chlorinated congeners and significantly correlated with altitude. The PAH profile for water and soil samples showed the main contribution of pyrogenic PAHs due to emissions of solid combustion, whereas the profile for sediments indicated the main contribution of pyrogenic PAHs from gasoline emissions. The PAH levels measured in Himalayan samples must be considered as low to medium contaminated, whereas the regarded Himalayan stations can be considered undisturbed remote areas concerning PCB, PBDE and OC compounds. PMID:21752503

  10. Influence of eutrophication on air-water exchange, vertical fluxes, and phytoplankton concentrations of persistent organic pollutants

    SciTech Connect

    Dachs, J.; Eisenreich, S.J.; Hoff, R.M.

    2000-03-15

    The influence of eutrophication on the biogeochemical cycles of persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) is largely unknown. In this paper, the application of a dynamic air-water-phytoplankton exchange model to Lake Ontario is used as a framework to study the influence of eutrophication on air-water exchange, vertical fluxes, and phytoplankton concentrations of POPs. The results of these simulations demonstrate that air-water exchange controls phytoplankton concentrations in remote aquatic environments with little influence from land-based sources of pollutants and supports levels in even historically contaminated systems. Furthermore, eutrophication or high biomass leads to a disequilibrium between the gas and dissolved phase, enhanced air-water exchange, and vertical sinking fluxes of PCBs. Increasing biomass also depletes the water concentrations leading to lower than equilibrium PCB concentrations in phytoplankton. Implications to future trends in PCB pollution in Lake Ontario are also discussed.

  11. Persistence and degradation of new β-lactam antibiotics in the soil and water environment.

    PubMed

    Braschi, I; Blasioli, S; Fellet, C; Lorenzini, R; Garelli, A; Pori, M; Giacomini, D

    2013-09-01

    The development of new antibiotics with low environmental persistence is of utmost importance in contrasting phenomena of antibiotic resistance. In this study, the persistence of two newly synthesized monocyclic β-lactam antibiotics: (2R)-1-(methylthio)-4-oxoazetidin-2-yl acetate, P1, and (2R,3R)-3-((1R)-1-(tert-butyldimethylsilanyloxy)ethyl)-1-(methylthio)-4-oxoazetidin-2-yl acetate, P2, has been investigated in water in the pH range 3-9 and in two (calcareous and forest) soils, then compared to amoxicillin, a β-lactam antibiotic used in human and veterinary medicine. P1 and P2 persistence in water was lower than that of amoxicillin with only a few exceptions. P1 hydrolysis was catalyzed at an acidic pH whereas P2 hydrolysis takes place at both acidic and alkaline pH values. P1 persistence in soils depended mainly on their water potential (t1/2: 35.0-70.7d at wilting point; <1d at field capacity) whereas for P2 it was shorter and unaffected by soil water content (t1/2 0.13-2.5d). Several degradation products were detected in soils at both water potentials, deriving partly from hydrolytic pathways and partly from microbial transformation. The higher LogKow value for P2 compared with P1 seemingly confers P2 with high permeability to microbial membranes regardless of soil water content. P1 and P2 persistence in soils at wilting point was shorter than that of amoxicillin, whereas it had the same extent at field capacity.

  12. Persistent Smoking after a Diagnosis of Lung Cancer is Associated with Higher Reported Pain Levels

    PubMed Central

    Daniel, Marcella; Keefe, Francis J.; Lyna, Pauline; Peterson, Bercedis; Garst, Jennifer; Kelley, Mike; Bepler, Gerald; Bastian, Lori A.

    2009-01-01

    The purpose of this study is to evaluate the impact of smoking status after a diagnosis of lung cancer on reported pain levels. We conducted a telephone survey of patients with lung cancer identified from four participating sites between September 2004 and July 2006. Patients were asked to rate their usual pain level over the past week on a 0-10 rating scale on which 0 was ‘no pain’ and 10 ‘pain as bad as you can imagine’. We operationally defined persistent smokers as patients who reported continuing to smoke after their lung cancer diagnosis. A logistic regression analyses was used to test the hypothesis that persistent smokers report higher usual pain levels than non-smokers. Overall, 893 patients completed the survey. The majority (76%) was found to have advanced cancer (Stages IIIb and IV). The mean age was 63 (SD=10). Seventeen percent of the patients studied were categorized as persistent smokers. The mean pain score for the study sample was 3.1 (sd=2.7) and 41% reported moderate (4-6) or severe pain (7-10). A greater proportion of persistent smokers reported moderate or severe pain than non-smokers or former smokers (p<.001). Logistic regression analysis revealed that, smoking status was associated with the usual pain even after adjusting for age, perceived health status and other lung cancer symptoms such as dyspnea, fatigue and trouble eating. In conclusion, patients who continue to smoke after a diagnosis of lung cancer report higher levels of usual pain than non-smokers or former smokers. More research is needed to understand the mechanisms that relate nicotine intake to pain and disease progression in late-stage lung cancer. Perspective This article examines the relationship between pain and persistent smoking in patients with lung cancer. Although more research is needed to understand the mechanisms that relate nicotine intake to pain and disease progression, physicians can promote smoking cessation in patients with lung cancer to improve

  13. Persistence of Nontuberculous Mycobacteria in a Drinking Water System after Addition of Filtration Treatment

    PubMed Central

    Hilborn, Elizabeth D.; Covert, Terry C.; Yakrus, Mitchell A.; Harris, Stephanie I.; Donnelly, Sandra F.; Rice, Eugene W.; Toney, Sean; Bailey, Stephanie A.; Stelma, Gerard N.

    2006-01-01

    There is evidence that drinking water may be a source of infections with pathogenic nontuberculous mycobacteria (NTM) in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular colonization of protozoa. Our goal was to determine whether we could detect a reduction in the prevalence of NTM recovered from an unfiltered surface drinking water system after the addition of ozonation and filtration treatment and to characterize NTM isolates by using molecular methods. We sampled water from two initially unfiltered surface drinking water treatment plants over a 29-month period. One plant received the addition of filtration and ozonation after 6 months of sampling. Sample sites included those at treatment plant effluents, distributed water, and cold water taps (point-of-use [POU] sites) in public or commercial buildings located within each distribution system. NTM were recovered from 27% of the sites. POU sites yielded the majority of NTM, with >50% recovery despite the addition of ozonation and filtration. Closely related electrophoretic groups of Mycobacterium avium were found to persist at POU sites for up to 26 months. Water collected from POU cold water outlets was persistently colonized with NTM despite the addition of ozonation and filtration to a drinking water system. This suggests that cold water POU outlets need to be considered as a potential source of chronic human exposure to NTM. PMID:16957205

  14. Elevated Systemic Levels of Inflammatory Cytokines in Older Women with Persistent Cervical HPV Infection1234

    PubMed Central

    Kemp, Troy J.; Hildesheim, Allan; García-Piñeres, Alfonso; Williams, Marcus C.; Shearer, Gene M.; Rodriguez, Ana Cecilia; Schiffman, Mark; Burk, Robert; Freer, Enrique; Bonilla, Jose; Herrero, Rolando; Pinto, Ligia A.

    2010-01-01

    Background Defects in lymphoproliferative responses to mitogen/antigens in women >45 years old ith a persistent type-specific HPV infection have been reported. Methods To determine whether these defects were associated with altered cytokine profiles, plasma and PBMC culture supernatants from 50 cases (persistent HPV infection and weak lymphoproliferative responses) and 50 uninfected controls were examined for 24 cytokines using multiplexed bead-based immunoassays and enzyme-linked immunosorbent assay (ELISA). Results The following plasma cytokines were significantly increased from cases relative to controls: (cases vs. controls (median pg/ml); IL-6: 393.1 vs. 14.5, IL-8: 1128.5 vs. 43.9, TNF-α: 164.1 vs. 9.2, MIP-1α: 1368.9 vs. 25.5, GM-CSF: 13.8 vs. 7.3, IL-1β: 8.3 vs. 1.6, all p<0.0001, and IL-1α: 218.2 vs. 169.5, p=0.02). We focused our analysis on the following cytokines: IL-6, IL-8, TNF-α, and MIP-1α due to high fold change (>10) and highly statistically significant difference between cases and controls. Moreover, length of persistence or type of infection (high risk and low risk) did not affect these differences. IL-6, TNF-α, MIP-1α levels were increased in unstimulated PBMC culture supernatants from cases compared to controls (p <0.05), except for IL-8 (p=0.09). However, the cytokine levels from PHA-stimulated PBMC culture supernatants were significantly lower in the cases (p<0.0001). Conclusions Persistent HPV infection in older women with evidence of immune deficit is associated with an increase in systemic inflammatory cytokines. Impact Future studies are needed to determine whether the inflammatory profile is age dependent and to examine the role inflammatory cytokines play in HPV-induced progression from infection to cervical cancer. PMID:20647411

  15. High Holocene lake levels in eastern Patagonia (Argentina) as a result of persistent Atlantic rainfall (Invited)

    NASA Astrophysics Data System (ADS)

    Ariztegui, D.; Compagnucci, R.; Agosta, E. A.

    2013-12-01

    Today's precipitation in central Patagonia, Argentina, mostly follows the intensity of the Westerlies. However, the extraordinary persistence of daily easterly winds can trigger episodes of intense rainfall reflected as water level variations in Lago Cardiel, a closed lacustrine basin located at 49°S. Meteorological data from 11-20 March 2002 at nearby Gobernador Gregores station recorded a heavy rain spell of 50mm accounting for 30% of the mean annual rainfall (167mm/year). The synoptic situation during this interval shows rainfall produced by wet air mass advection from the Atlantic. The weather surface maps for these days display a cyclone incoming at 45°S to the west of western Patagonia together with a concomitant anticyclone to the southwest, while a cyclogenesis initiates in eastern Patagonia. This pressure dipole produced east-north-eastern winds at the lake latitude and a generalized drop in the Westerlies intensity almost across the entire Patagonia. This is shown in distant stations such as Bariloche(41.9°S) and Rio Gallegos (51.4°S) in northwestern and southeastern Patagonia, respectively, as well as in Chilean stations such as Balmaceda (45.9°S) and Chile Chico (46.9°S). Similar pressure anomalies along with changes in wind intensity and direction have been previously simulated for the Austral winter (JJA) during the middle Holocene (7.0 to 4.5 kcal yrs BP). Thus, weaker Westerlies along with a higher frequency of the dipole-type atmospheric circulation than at present increased the described easterly winds-triggered rainfall. This inference agrees with high lake levels in the Lago Cardiel record along with more negative - Atlantic type - oxygen isotopic composition of authigenic carbonates. An increase in the frequency of this climatic configuration during longer time intervals could further explain the extreme lake highstands reconstructed for the early Holocene, and the contemporaneous negative isotopic signature of the carbonates. It could

  16. Investigation of persistent colonization by Pseudomonas aeruginosa-like strains in a spring water bottling plant.

    PubMed Central

    Morais, P V; Mesquita, C; Andrade, J L; da Costa, M S

    1997-01-01

    Ninety-seven strains, producing a fluorescent pigment under UV light and/or a green diffusive pigment on cetrimide-naladixic acid agar, were isolated from a spring water bottling plant. These strains were presumptively identified as Pseudomonas aeruginosa, but they could not be confirmed as strains of this species nor identified by the API 20NE identification system. The isolates and reference strains were clustered by computer-assisted whole-cell protein sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The numerical analysis of the protein electrophoregrams resulted in the formation of four clusters at a similarity level of 80% and two unclustered type strains. One cluster included strains isolated during a 4-month period and reference strains of several biotypes of P. fluorescens. The remaining isolates formed another cluster with a very high similarity of level, which included two groups of strains based on biochemical characterization by the API 20NE Test System. Strains were typed by random amplified polymorphic DNA (RAPD)-PCR and two different RAPD patterns were obtained, corresponding to each biochemical profile. This persistent colonization seems to be caused by a single species present in the bottling system, with two clonal origins, not related to P. aeruginosa or to any of the other type strains tested. Partial 16S rDNA sequence of a representative strain of one cluster of isolates had a level of similarity of 99.3% with P. alcaligenes. This study shows that characteristics similar to P. aeruginosa on cetrimide-naladixic acid agar can be exhibited by several groups of fluorescent pseudomonads that do not belong to this species, clearly showing that confirmation tests must be performed before a decision regarding the water quality is made. PMID:9055406

  17. Comparative Persistence of Subgroups of F-Specific RNA Phages in River Water

    PubMed Central

    Yang, Yongheng

    2013-01-01

    F-specific (F+) RNA phages are widely used as indicators for the presence of fecal contamination and/or enteric viruses in water, and identifying subgroups of F+ RNA phages provides an approach for microbial source tracking. Different survival characteristics of the F+ RNA phage subgroups result in a misinterpretation of their original proportion in water, thus giving misleading information when they are used for microbial source tracking. This study investigated the comparative persistence of subgroups of F+ RNA phages in river water under different conditions. Results suggested that temperature and pH are the major factors affecting the persistence of F+ RNA phages in river water, and organic substances promote phage survival. The comparative persistence patterns of subgroups of F+ RNA phages varied and may bias extrapolation of their initial proportions in surface water. Thus, the characteristics of water should be taken into consideration and the results should be carefully interpreted when F+ RNA phages are used for microbial source tracking. PMID:23686274

  18. Open-system coral ages reveal persistent suborbital sea-level cycles.

    PubMed

    Thompson, William G; Goldstein, Steven L

    2005-04-15

    Sea level is a sensitive index of global climate that has been linked to Earth's orbital variations, with a minimum periodicity of about 21,000 years. Although there is ample evidence for climate oscillations that are too frequent to be explained by orbital forcing, suborbital-frequency sea-level change has been difficult to resolve, primarily because of problems with uranium/thorium coral dating. Here we use a new approach that corrects coral ages for the frequently observed open-system behavior of uranium-series nuclides, substantially improving the resolution of sea-level reconstruction. This curve reveals persistent sea-level oscillations that are too frequent to be explained exclusively by orbital forcing.

  19. Resolution Enhancement of MODIS-Derived Water Indices for Studying Persistent Flooding

    NASA Technical Reports Server (NTRS)

    Underwood, L. W.; Kalcic, Maria; Fletcher, Rose

    2012-01-01

    -m MODIS, with enhanced features, and the approximated daily 30-m high-resolution image based on Landsat data. The algorithm was developed and tested over the Calcasieu-Sabine Basin, which was heavily inundated by storm surge from Hurricane Ike to study the extent and duration of flooding following the storm. Time series for 2000-2009, covering flooding events by Hurricane Rita in 2005 and Hurricane Ike in 2008, were derived. High resolution images were formed for all days in 2008 between the first cloud free Landsat scene and the last cloud-free Landsat scene. To refine and validate flooding maps, each time series was compared to Louisiana Coastwide Reference Monitoring System (CRMS) station water levels adjusted to marsh to optimize thresholds for MODIS-derived time series of NDWI. Seasonal fluctuations were adjusted by subtracting ten year average NDWI for marshes, excluding the hurricane events. Results from different NDWI indices and a combination of indices were compared. Flooding persistence that was mapped with higher-resolution data showed some improvement over the original MODIS time series estimates. The advantage of this novel technique is that improved mapping of extent and duration of inundation can be provided.

  20. Resolution Enhancement of MODIS-derived Water Indices for Studying Persistent Flooding

    NASA Astrophysics Data System (ADS)

    Underwood, L. W.; Kalcic, M. T.; Fletcher, R. M.

    2012-12-01

    -m MODIS, with enhanced features, and the approximated daily 30-m high-resolution image based on Landsat data. The algorithm was developed and tested over the Calcasieu-Sabine Basin, which was heavily inundated by storm surge from Hurricane Ike to study the extent and duration of flooding following the storm. Time series for 2000-2009, covering flooding events by Hurricane Rita in 2005 and Hurricane Ike in 2008, were derived. High resolution images were formed for all days in 2008 between the first cloud free Landsat scene and the last cloud-free Landsat scene. To refine and validate flooding maps, each time series was compared to Louisiana Coastwide Reference Monitoring System (CRMS) station water levels adjusted to marsh to optimize thresholds for MODIS-derived time series of NDWI. Seasonal fluctuations were adjusted by subtracting ten year average NDWI for marshes, excluding the hurricane events. Results from different NDWI indices and a combination of indices were compared. Flooding persistence that was mapped with higher-resolution data showed some improvement over the original MODIS time series estimates. The advantage of this novel technique is that improved mapping of extent and duration of inundation can be provided.

  1. Juvenile chemical sediments and the long term persistence of water at the surface of Mars

    NASA Astrophysics Data System (ADS)

    Tosca, Nicholas J.; Knoll, Andrew H.

    2009-09-01

    Chemical sediments and the aqueous alteration products of volcanic rocks clearly indicate the presence of water, at least episodically, at the Martian surface. Compared to similar materials formed on the early Earth, however, Martian deposits are juvenile, or diagenetically under-developed. Here we examine the role of water in facilitating various diagenetic reactions and evaluate the predicted effects of time and temperature for aqueous diagenesis on Mars. Using kinetic formulations based on terrestrial sedimentary geology, we quantify the integrated effects of time and temperature for a range of possible burial and thermal histories of precipitated minerals on Mars. From this, we estimate thresholds beyond which these precipitates should have been converted to the point of non-detection in the presence of water. Surface water has been shown to be at least episodically present in recent times. Nonetheless, the integrated duration of aqueous activity recorded over geologically long intervals by hydrated amorphous silica, smectite clays and Fe-sulfate minerals suggests that where these minerals occur water did not persist much beyond their initial deposition. This geochemical conclusion converges with geomorphologic studies that suggest water limitation during the late Noachian-Hesperian peak of valley formation and a still more limited footprint of water since that time. In addition to documenting the presence of water and its chemical properties, a complete assessment of potentially habitable environments on Mars should address the timescales on which liquid water has persisted and the timing of aqueous episodes relative to major planetary events.

  2. Viral Replication, Persistence in Water and Genetic Characterization of Two Influenza A Viruses Isolated from Surface Lake Water

    PubMed Central

    Lebarbenchon, Camille; Yang, My; Keeler, Shamus P.; Ramakrishnan, Muthannan A.; Brown, Justin D.; Stallknecht, David E.; Sreevatsan, Srinand

    2011-01-01

    Water-borne transmission has been suggested as an important transmission mechanism for Influenza A (IA) viruses in wild duck populations; however, relatively few studies have attempted to detect IA viruses from aquatic habitats. Water-isolated viruses have rarely been genetically characterized and evaluation for persistence in water and infectivity in natural hosts has never been documented. In this study, we focused on two IA viruses (H3N8 and H4N6 subtypes) isolated from surface lake water in Minnesota, USA. We investigated the relative prevalence of the two virus subtypes in wild duck populations at the sampling site and their genetic relatedness to IA viruses isolated in wild waterbirds in North America. Viral persistence under different laboratory conditions (temperature and pH) and replication in experimentally infected Mallards (Anas platyrhynchos) were also characterized. Both viruses were the most prevalent subtype one year following their isolation in lake water. The viruses persisted in water for an extended time period at constant temperature (several weeks) but infectivity rapidly reduced under multiple freeze-thaw cycles. Furthermore, the two isolates efficiently replicated in Mallards. The complete genome characterization supported that these isolates originated from genetic reassortments with other IA viruses circulating in wild duck populations during the year of sampling. Based on phylogenetic analyses, we couldn't identify genetically similar viruses in duck populations in the years following their isolation from lake water. Our study supports the role for water-borne transmission for IA viruses but also highlights that additional field and experimental studies are required to support inter-annual persistence in aquatic habitats. PMID:22028909

  3. Halogenated persistent organic pollutants in relation to trophic level in deep sea fish.

    PubMed

    Webster, Lynda; Russell, Marie; Walsham, Pam; Hussy, Ines; Lacaze, Jean-Pierre; Phillips, Lesley; Dalgarno, Eric; Packer, Gill; Neat, Francis; Moffat, Colin F

    2014-11-15

    The bioaccumulation of persistent organic pollutants (POPs) in deep sea fish from the Rockall fishing area was investigated. Predator and prey species were analysed for stable isotopes, fatty acids, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). δ(15)N indicated that black scabbard was at the highest trophic level and the prey the lowest. The fatty acid signatures indicated that black scabbard and black dogfish fed at a higher trophic level compared to the roundnose grenadier. PCBs and PBDEs were detected in the liver of all three predator species. PCB concentrations were significantly higher in the roundnose grenadier, possibly due to their longer life span. PCB concentrations were compared to OSPAR assessment criteria, concentrations were above background but below Environmental Assessment Criteria for all but one congener. PCB concentrations were below food safety levels in the flesh, but exceeded the limit for liver in the roundnose grenadier and black dogfish.

  4. The level and persistence of equatorial spread F recorded daily during a year at solar maximum

    NASA Astrophysics Data System (ADS)

    Whalen, J. A.

    2001-05-01

    The prediction of equatorial bubbles, and of the resulting scintillation that disrupts trans-ionospheric communication and radar, is a particularly difficult problem of space weather. The fact that bubbles occur essentially at random prevents the systematic observation of their formation, hence progress in their prediction. However what can be observed systematically is the occurrence of strong bottomside spread F (BSSF), which is a necessary condition for bubble formation, and lower levels of BSSF which preclude this formation. This work records for the first time, spread F conditions on each day of a year at solar maximum. Using an array of ionospheric sounders located in the Western Hemisphere, four levels of spread F are recorded: three BSSF of no, weak, and strong; and the fourth as macroscopic bubbles. Because each irregularity level corresponds to a threshold level of maximum pre-reversal E x B drift velocity, the record of BSSF implies also a record of this fundamental parameter. Of particular importance, a given level of irregularity can persist for periods of as many as 10 successive days. Furthermore these periods can recur with the 27 day solar rotation period. Some of these periods correspond to recurring periods of magnetic activity, strong BSSF and bubbles to the lowest magnetic activity, and weak and no BSSF to the highest magnetic activity. Also considered is the relation to 10.7 cm solar flux which varies between 150-350 solar flux units during the year and often by that amount during a single solar rotation. However the influence of solar flux on irregularity level or on its persistence has yet to be determined. The examination of recurrence with solar rotation is limited because only 13.5 rotations occur during the year. In addition there is the limitation of seasonal dependence, especially because irregularity nearly disappears during Jun. and Jul. In addition, strong BSSF is maximum in Jan. and Dec., whereas strong BSSF accompanied by

  5. Strengthening STEM performance and persistence: Influence of undergraduate teaching assistants on entry-level STEM students

    NASA Astrophysics Data System (ADS)

    Philipp, Stephanie B.

    Increasing retention of students in science, technology, engineering, or mathematics (STEM) programs of study is a priority for many colleges and universities. This study examines an undergraduate teaching assistant (UTA) program implemented in a general chemistry course for STEM majors to provide peer learning assistance to entrylevel students. This study measured the content knowledge growth of UTAs compared to traditional graduate teaching assistants (GTAs) over the semester, and described the development of peer learning assistance skills of the UTAs as an outcome of semesterlong training and support from both science education and STEM faculty. Impact of the UTA program on final exam grades, persistence of students to enroll in the next chemistry course required by their intended major, and STEM identity of students were estimated. The study sample comprised 284 students in 14 general chemistry recitation sections led by six UTAs and 310 students in 15 general chemistry recitation sections led by three traditional GTAs for comparison. Results suggested that both UTAs and GTAs made significant learning gains in general chemistry content knowledge, and there was no significant difference in content knowledge between UTA and GTA groups. Student evaluations, researcher observations, and chemistry faculty comments confirm UTAs were using the learning strategies discussed in the semester-long training program. UTA-led students rated their TAs significantly higher in teaching quality and student care and encouragement, which correlated with stronger STEM recognition by those students. The results of hierarchical linear model (HLM) analysis showed little variance in final exam grades explained by section-level variables; most variance was explained by student-level variables: mathematics ACT score, college GPA, and intention to enroll in the next general chemistry course. Students having higher college GPAs were helped more by having a UTA. Results from logistic

  6. The drinking water disparities framework: on the origins and persistence of inequities in exposure.

    PubMed

    Balazs, Carolina L; Ray, Isha

    2014-04-01

    With this article, we develop the Drinking Water Disparities Framework to explain environmental injustice in the context of drinking water in the United States. The framework builds on the social epidemiology and environmental justice literatures, and is populated with 5 years of field data (2005-2010) from California's San Joaquin Valley. We trace the mechanisms through which natural, built, and sociopolitical factors work through state, county, community, and household actors to constrain access to safe water and to financial resources for communities. These constraints and regulatory failures produce social disparities in exposure to drinking water contaminants. Water system and household coping capacities lead, at best, to partial protection against exposure. This composite burden explains the origins and persistence of social disparities in exposure to drinking water contaminants.

  7. The Drinking Water Disparities Framework: On the Origins and Persistence of Inequities in Exposure

    PubMed Central

    Balazs, Carolina L.; Ray, Isha

    2014-01-01

    With this article, we develop the Drinking Water Disparities Framework to explain environmental injustice in the context of drinking water in the United States. The framework builds on the social epidemiology and environmental justice literatures, and is populated with 5 years of field data (2005–2010) from California’s San Joaquin Valley. We trace the mechanisms through which natural, built, and sociopolitical factors work through state, county, community, and household actors to constrain access to safe water and to financial resources for communities. These constraints and regulatory failures produce social disparities in exposure to drinking water contaminants. Water system and household coping capacities lead, at best, to partial protection against exposure. This composite burden explains the origins and persistence of social disparities in exposure to drinking water contaminants. PMID:24524500

  8. Levels of persistent organic pollutant and their predictors among young adults

    PubMed Central

    Gallo, Mia V.; Schell, Lawrence M.; DeCaprio, Anthony P.; Jacobs, Agnes

    2011-01-01

    Exposure to persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethane (p,p’-DDE), and hexachlorobenzene (HCB) continues to be of concern due to their ubiquitous distribution and high persistence. Current toxicant body burden is still a primary concern within the Akwesasne Mohawk Nation since other studies conducted within the community have shown relationships between these POPs and endocrine disruption. In this article we describe the levels of these toxicants in young adults of the Akwesasne Mohawk Nation between the ages of 17 and 21 years of age (mean age 18.1 years), and investigate potential influences of their current body-burden. Seventeen congeners in fourteen chromatographic peaks were detected in 50% or more of the individuals sampled (geometric mean [GM] of the sum of these congeners = 0.43 ppb). Congeners 118, 138[+163+164] and 153 had the highest rate of detection (≥ 98%) within the Akwesasne youth. Of the other organochlorines, HCB (GM= 0.04 ppb) and p,p’-DDE (GM=0.38 ppb) were found in 100% and 99% of the sample respectively. Significantly higher levels of PCBs were found among individuals who were breastfed as infants, were first born, or had consumed local fish within the past year. When compared to levels of p,p’-DDE, HCB, and 13 specific congeners reported by the CDC for youth between the ages of 12 and 19 years, the geometric means of several congeners (CBs 99, 105, 110, and 118) among the Akwesasne were higher than the reported CDC 90th percentile. In contrast, levels of CB 28 in Akwesasne youth were ∼50% or less than those of the CDC cohort. p,p’-DDE and HCB levels were generally higher in the CDC cohort (GM of 0.516 and 0.065 ppb, respectively for Mohawks vs. 2.51 and 0.123, respectively, for CDC). Concentrations of non-persistent PCBs among this sample of Akwesasne young adults were higher than those reported by the CDC suggesting continued exposure, but lower than those

  9. Reactive airways dysfunction syndrome. Case reports of persistent airways hyperreactivity following high-level irritant exposures.

    PubMed

    Brooks, S M; Weiss, M A; Bernstein, I L

    1985-07-01

    Two individuals developed an asthma-like illness after a single exposure to high levels of an irritating aerosol, vapor, fume, or smoke. Symptoms developed within a few hours. A consistent physiologic accompaniment was airways hyperreactivity, with the two subjects showing positive methacholine challenge tests. No documented preexisting respiratory illness was identified, nor did subjects relate past respiratory complaints. Respiratory symptoms and airways hyperreactivity persisted for at least four years after the incident. The incriminated etiologic agents all shared a common characteristic of being irritant in nature. Bronchial biopsy specimens showed an airways inflammatory response. This report suggests that acute high-level irritant exposures may produce an asthma-like syndrome in some individuals, with long-term sequelae and chronic airways disease. Nonimmunologic mechanisms seems to be operative in the pathogenesis of this syndrome.

  10. Is the fact of parenting couples cohabitation affecting the serum levels of persistent organohalogen pollutants?

    PubMed

    Góralczyk, Katarzyna; Struciński, Paweł; Wojtyniak, Bogdan; Rabczenko, Daniel; Lindh, Christian H; Jönsson, Bo A G; Toft, Gunnar; Lenters, Virissa; Czaja, Katarzyna; Hernik, Agnieszka; Bonde, Jens Peter; Pedersen, Henning S; Zvyezday, Valentyna; Ludwicki, Jan K

    2015-06-01

    Organohalogen compounds constitute one of the important groups of persistent organic pollutants (POPs). Among them, due to their long-term health effects, one should pay attention on organochlorine pesticides, polychlorinated biphenyls (PCBs) and perfluoroalkylated substances (PFASs). This paper is an attempt to answer the question about relation between the fact of cohabitation by couples expecting a child and the level of the organohalogen compounds in the blood serum of both parents. The study was done on a population of parent couples from Greenland, Poland and Ukraine, from whom blood samples were collected in order to establish the levels of marker organohalogen compounds. We selected, as the representative of these compounds, the most persistent metabolite of DDT, i.e. p,p'-DDE, the most frequently detected PCB congener - CB-153, and PFOS and PFOA as the representatives of PFASs. The results show that in case of all compounds under study the highest concentrations were present always in men in relation to the levels detected in the blood serum of their female partners, regardless of the country of origin of the couple. A positive correlation was noted between the concentrations of the studied compounds in the blood serum of men and women in parenting couples. In some cases these correlations were statistically significant, e.g. for concentrations of p,p'-DDE in pairs from Greenland and Ukraine, of CB-153 in pairs from Poland and Ukraine, and of PFOS for parents from Greenland and Poland, while for PFOA - only for couples from Greenland. The concentrations of the compounds included in the study were similar to the levels found in general population in other countries. Our results show that the exposure to POPs resulting from cohabitation plays a role in the general exposure to these compounds.

  11. Salt marsh persistence is threatened by predicted sea-level rise

    NASA Astrophysics Data System (ADS)

    Crosby, Sarah C.; Sax, Dov F.; Palmer, Megan E.; Booth, Harriet S.; Deegan, Linda A.; Bertness, Mark D.; Leslie, Heather M.

    2016-11-01

    Salt marshes buffer coastlines and provide critical ecosystem services from storm protection to food provision. Worldwide, these ecosystems are in danger of disappearing if they cannot increase elevation at rates that match sea-level rise. However, the magnitude of loss to be expected is not known. A synthesis of existing records of salt marsh elevation change was conducted in order to consider the likelihood of their future persistence. This analysis indicates that many salt marshes did not keep pace with sea-level rise in the past century and kept pace even less well over the past two decades. Salt marshes experiencing higher local sea-level rise rates were less likely to be keeping pace. These results suggest that sea-level rise will overwhelm most salt marshes' capacity to maintain elevation. Under the most optimistic IPCC emissions pathway, 60% of the salt marshes studied will be gaining elevation at a rate insufficient to keep pace with sea-level rise by 2100. Without mitigation of greenhouse gas emissions this potential loss could exceed 90%, which will have substantial ecological, economic, and human health consequences.

  12. Levels and Seasonal Variability of Persistent Organic Pollutants in Rural and Urban Atmosphere of Southern Ghana

    NASA Astrophysics Data System (ADS)

    Adu-Kumi, Sam; Klanova, Jana; Holoubek, Ivan

    2010-05-01

    Concentrations of persistent organic pollutants (POPs) in air are reported from the first full year of the RECETOX-Africa Air Monitoring (MONET_AFRICA) Project. Passive air samplers composed of polyurethane foam disks (PUF-disk samplers) were deployed for sampling background air concentrations from January-December 2008 at two urban sites in Ghana, namely, Ghana Atomic Energy Commission (Biotechnology and Nuclear Agricultural Research Institute, Kwabenya); and Ghana Meteorological Agency (East Legon). Another set of PUF-disk samplers were deployed at a rural/agricultural location (Lake Bosumtwi) from July-November 2008. For the purposes of this study, 28 days was the sampling period for polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs); and 3 months for OCPs (Drins) and dioxins/furans (PCDD/Fs) respectively. MONET_AFRICA constituted part of the activities under the Global Monitoring Plan (GMP) for the effectiveness evaluation (Article 16) of the Stockholm Convention on POPs and the air sampling survey was conducted at 26 sites across the African continent with the aim to establish baseline information on contamination of ambient air with persistent organic pollutants (POPs) as a reference for future monitoring programmes in the region. For the pesticides, endosulfans constituted the highest contaminants measured followed by HCHs and DDTs in that order. The large temporal variability in the pesticide concentrations suggested seasonal application of endosulfans and γ-HCH. Levels of endosulfans were initially found to be below detection limit during the first sampling period (January - March 2008) but recorded the highest concentration than any other pesticide from all 16 sites in the African region during the second sampling period (April - June 2008). Concentrations of DDTs and HCHs were generally low throughout the sampling periods. p,p'-DDE/p,p'-DDT ratio in ambient air showed that the metabolite DDE was the

  13. Persistent Water-Nitric Acid Condensate with Saturation Water Vapor Pressure Greater than That of Hexagonal Ice.

    PubMed

    Gao, Ru-Shan; Gierczak, Tomasz; Thornberry, Troy D; Rollins, Andrew W; Burkholder, James B; Telg, Hagen; Voigt, Christiane; Peter, Thomas; Fahey, David W

    2016-03-10

    A laboratory chilled mirror hygrometer (CMH), exposed to an airstream containing water vapor (H2O) and nitric acid (HNO3), has been used to demonstrate the existence of a persistent water-nitric acid condensate that has a saturation H2O vapor pressure greater than that of hexagonal ice (Ih). The condensate was routinely formed on the mirror by removing HNO3 from the airstream following the formation of an initial condensate on the mirror that resembled nitric acid trihydrate (NAT). Typical conditions for the formation of the persistent condensate were a H2O mixing ratio greater than 18 ppm, pressure of 128 hPa, and mirror temperature between 202 and 216 K. In steady-state operation, a CMH maintains a condensate of constant optical diffusivity on a mirror through control of only the mirror temperature. Maintaining the persistent condensate on the mirror required that the mirror temperature be below the H2O saturation temperature with respect to Ih by as much as 3 K, corresponding to up to 63% H2O supersaturation with respect to Ih. The condensate was observed to persist in steady state for up to 16 h. Compositional analysis of the condensate confirmed the co-condensation of H2O and HNO3 and thereby strongly supports the conclusion that the Ih supersaturation is due to residual HNO3 in the condensate. Although the exact structure or stoichiometry of the condensate could not be determined, other known stable phases of HNO3 and H2O are excluded as possible condensates. This persistent condensate, if it also forms in the upper tropical troposphere, might explain some of the high Ih supersaturations in cirrus and contrails that have been reported in the tropical tropopause region. PMID:26447682

  14. Persistent Water-Nitric Acid Condensate with Saturation Water Vapor Pressure Greater than That of Hexagonal Ice.

    PubMed

    Gao, Ru-Shan; Gierczak, Tomasz; Thornberry, Troy D; Rollins, Andrew W; Burkholder, James B; Telg, Hagen; Voigt, Christiane; Peter, Thomas; Fahey, David W

    2016-03-10

    A laboratory chilled mirror hygrometer (CMH), exposed to an airstream containing water vapor (H2O) and nitric acid (HNO3), has been used to demonstrate the existence of a persistent water-nitric acid condensate that has a saturation H2O vapor pressure greater than that of hexagonal ice (Ih). The condensate was routinely formed on the mirror by removing HNO3 from the airstream following the formation of an initial condensate on the mirror that resembled nitric acid trihydrate (NAT). Typical conditions for the formation of the persistent condensate were a H2O mixing ratio greater than 18 ppm, pressure of 128 hPa, and mirror temperature between 202 and 216 K. In steady-state operation, a CMH maintains a condensate of constant optical diffusivity on a mirror through control of only the mirror temperature. Maintaining the persistent condensate on the mirror required that the mirror temperature be below the H2O saturation temperature with respect to Ih by as much as 3 K, corresponding to up to 63% H2O supersaturation with respect to Ih. The condensate was observed to persist in steady state for up to 16 h. Compositional analysis of the condensate confirmed the co-condensation of H2O and HNO3 and thereby strongly supports the conclusion that the Ih supersaturation is due to residual HNO3 in the condensate. Although the exact structure or stoichiometry of the condensate could not be determined, other known stable phases of HNO3 and H2O are excluded as possible condensates. This persistent condensate, if it also forms in the upper tropical troposphere, might explain some of the high Ih supersaturations in cirrus and contrails that have been reported in the tropical tropopause region.

  15. Estimating Persistent Mass Flux of Volatile Contaminants from the Vadose Zone to Ground Water

    SciTech Connect

    Truex, Michael J.; Oostrom, Martinus; Brusseau, Mark

    2009-05-04

    Contaminants may persist for long time periods within low permeability portions of the vadose zone where they cannot be effectively treated and are a potential continuing source of contamination to groundwater. Setting appropriate vadose zone remediation goals requires evaluating these persistent sources in terms of their impact on meeting groundwater remediation goals. One-dimensional approaches for estimating transport of volatile contaminants in the vadose zone are considered and compared to a one-dimensional flux-continuity-based assessment of vapor-phase contaminant movement from the vadose zone to the groundwater. The flux-continuity-based assessment demonstrates that the ability of the groundwater to move contaminant away from the water table controls the vapor-phase mass flux from the vadose zone across the water table. Limitations of the one-dimensional approaches are then discussed with respect to the need for further method development and application of two- or three-dimensional numerical modeling. The carbon tetrachloride (CT) plume at the U.S. Department of Energy Hanford Site is used as an example of a site where persistent vadose zone contamination needs to be considered in the context of groundwater remediation.

  16. The persistent microbicidal effect in water exposed to the corona discharge.

    PubMed

    Julák, Jaroslav; Scholtz, Vladimír; Kotúčová, Soňa; Janoušková, Olga

    2012-07-01

    This article describes and particularly explains a new phenomenon of persistent microbicidal effect of water previously exposed to the low-temperature plasma, which cannot be attributed to the acidification only. The direct microbicidal action of plasma is well documented, being mediated by number of reactive particles with a short lifetime. However, we observed the microbicidal effect also in exposed water stored for a month, where it must be mediated by stable particles. In water and in phosphate-buffered saline, the formation of NO(x) and corresponding acids, H(2)O(2) and O(3) was confirmed after exposition to the low-temperature plasma generated in air by DC negative glow corona and positive streamer discharge. The time course of acidification, H(2)O(2) and O(3) formation were deremined. Except uncertain traces of HCN, SIFT-MS analysis of exposed liquids reveals no additional reactive compounds. The microbicidal effect persists almost unchanged during 4 weeks of storage, although O(3) completely and H(2)O(2) almost disappears. Staphylococcus epidermidis and Escherichia coli were inactivated within 10 min of incubation in exposed liquids, Candida albicans needs at least 1 h. The solutions prepared by artificial mixing of reactive compounds mimic the action of exposed water, but in lesser extent. The acid milieu is the main cause of the microbicidal effect, but the possibility of still unidentified additional compound remains open. PMID:21925912

  17. Evidence for high-level feature encoding and persistent memory during auditory stream segregation.

    PubMed

    Weintraub, David M; Snyder, Joel S

    2015-12-01

    A test sequence of alternating low-frequency (A) and high-frequency (B) tones in a repeating ". . . ABAB . . ." pattern is more likely to be heard as 2 segregated streams of tones when it is preceded by an isofrequency inducer sequence whose frequency matches either the A- or B-tone frequency (e.g., ". . . BBBB . . .") of the test, a phenomenon referred to as stream biasing. Low-level processes such as stimulus-selective adaptation of frequency-tuned neurons within early auditory processing stages have been thought by some to mediate stream biasing; however, the current study tested for the involvement of higher level processes. Inducers whose frequency matched neither the A- nor B-tone frequency (e.g., ". . . CCCC . . .") sometimes facilitated stream biasing. Stream biasing was also sensitive to complex features of the inducer sequence, namely whether the rhythmic pattern of the inducer matched the rhythm of the ABAB test. Stream biasing occurred even when an 8-s silent interval separated the inducer and test sequences, a time span longer than previously recognized (Beauvois & Meddis, 1997). These results suggest the involvement of persistent activation of high-level representations that affect perception. PMID:26375631

  18. Persistence of two Trichomonas gallinae isolates in chlorinated and distilled water with or without organic material.

    PubMed

    Gerhold, Richard W; Maestas, Lauren P; Harnage, Philip M

    2013-09-01

    Trichomonas gallinae is a protozoan parasite commonly found in columbids, passerines, and raptors. In passerines and columbids, trichomonosis causes significant morbidity and mortality associated with contaminated bird feeders and waters. However, there has been little work on the persistence of T. gallinae in water to determine if artificial waters are a likely source of infection for naive birds. To examine drinking water as a source of T. gallinae transmission, we inoculated 1 x 10(6) trichomonads into containers with 500 ml of either distilled or chlorinated water. In addition, we inoculated the same number of trichomonads in distilled or chlorinated water contaminated with 15 g organic matter. Aliquots of 0.5 ml were collected from each container at 0, 0.5, 1, 5, 10, or 20 min; inoculated into a Trichomonas culture packet; and incubated at 37 C for 6 days. Survival was best in the presence of organic matter, with either distilled or chlorinated water. Uncontaminated chlorinated water did not allow survival at any sampling period.

  19. Mountain Pine Beetle Impact on Stand-level Water Balance

    NASA Astrophysics Data System (ADS)

    Reilly, J. A.; Woods, S.

    2012-12-01

    The recent mountain pine beetle (MPB) epidemic has disturbed millions of hectares throughout the Rocky Mountain West. The most persistent effects of MPB infestation on the stand-level water balance are likely concomitant with the grey stage of the disturbance cycle. The grey stage occurs within 3 to 5 years of the initial infestation after the needles of an infected tree have turned red and fallen off due to tree death. Large numbers of grey-stage trees in a stand may remain on the landscape for up to 20 years, until windthrow or another disturbance sends them to the forest floor. The greater temporal persistence of the grey stage over antecedent stages suggested that an examination of the grey stage would best capture long-term effects of MPB disturbance on the forest water balance. In this study we hypothesized that changes to the forest canopy associated with MPB disturbance may affect the stand-level water balance. The needle loss and windthrow that follows MPB disturbance is expected to increase the amount of precipitation reaching the forest floor. Additionally, overstory evapotranspiration (ET) demand is expected to decrease as MPB-induced tree mortality increases within disturbed stands. The expected cumulative effect of MPB disturbance on the stand-level water balance is an increase in soil moisture due to increased precipitation inputs and reduced overstory ET. This study was conducted in Lubrecht Experimental Forest and adjacent Bureau of Land Management areas near Missoula, Montana. Sub-canopy measurements of soil moisture, precipitation (rain and snow water equivalent), overstory transpiration and micro-meteorological data (net radiation, temperature, wind speed, etc.) were collected in three 50 x 50 meter plots. The plots consisted of a uniform stand of grey-stage lodgepole pine, a uniform stand of non-infested lodgepole pine, and a recent clear-cut stand, which served as a control unit. Water balances for each stand were constructed using a mass

  20. Changes in persistent organic pollutant levels from adolescence to young adulthood

    PubMed Central

    Gallo, Mia V.; Deane, Glenn D.; DeCaprio, Anthony P.; Schell, Lawrence M.

    2015-01-01

    Elimination rates and their corresponding half-lives are conceptually important and intuitively accessible pharmacokinetic measures of toxicant elimination, but regression-based estimates are biased proportional to the degree of continuing (background) exposure. We propose an alternative estimator, the censored normal regression model, which uses all observations, but treats individuals whose initial level failed to exceed their follow-up level as censored observations to weight the regression estimates from those that declined between blood draws. In this manner, we derive the intrinsic elimination rate, the elimination rate free from ongoing exposure, as a parameter in a regression with an unobserved, latent dependent variable. We utilize sequential measurements of persistent organic pollutants (POPs) levels from adolescence to adulthood, a period of intense change in size and body composition, to quantify individual-level change within a community exposed to significant quantities of contaminants over an extended period of time. Although much research has been conducted on effects of POPs, far less attention has been given to vectors of intake and changes in toxicant levels during the life course. We apply exploratory factor analysis (EFA) to types and timing of consumption, along with physical behavioral characteristics, to identify a structure of seven underlying factors. Although several variables show factorial complexity, the latent constructs included an age/maturation and period-related factor, a nutritional composite, consumption prior to pregnancy, fish and fowl consumed during pregnancy, factors distinguishing body mass and weight from height, and bottom-feeding fish consumption. Unadjusted and adjusted half-lives using the censored normal regression estimator, as well as estimated half-lives from conventional log concentration regressions, are reported for PCB groupings, specific congeners, p,p′-DDE, and HCB. PMID:25863595

  1. Changes in persistent organic pollutant levels from adolescence to young adulthood.

    PubMed

    Gallo, Mia V; Deane, Glenn D; DeCaprio, Anthony P; Schell, Lawrence M

    2015-07-01

    Elimination rates and their corresponding half-lives are conceptually important and intuitively accessible pharmacokinetic measures of toxicant elimination, but regression-based estimates are biased proportional to the degree of continuing (background) exposure. We propose an alternative estimator, the censored normal regression model, which uses all observations, but treats individuals whose initial level failed to exceed their follow-up level as censored observations to weight the regression estimates from those that declined between blood draws. In this manner, we derive the intrinsic elimination rate, the elimination rate free from ongoing exposure, as a parameter in a regression with an unobserved, latent dependent variable. We utilize sequential measurements of persistent organic pollutants (POPs) levels from adolescence to adulthood, a period of intense change in size and body composition, to quantify individual-level change within a community exposed to significant quantities of contaminants over an extended period of time. Although much research has been conducted on effects of POPs, far less attention has been given to vectors of intake and changes in toxicant levels during the life course. We apply exploratory factor analysis (EFA) to types and timing of consumption, along with physical behavioral characteristics, to identify a structure of seven underlying factors. Although several variables show factorial complexity, the latent constructs included an age/maturation and period-related factor, a nutritional composite, consumption prior to pregnancy, fish and fowl consumed during pregnancy, factors distinguishing body mass and weight from height, and bottom-feeding fish consumption. Unadjusted and adjusted half-lives using the censored normal regression estimator, as well as estimated half-lives from conventional log concentration regressions, are reported for PCB groupings, specific congeners, p,p'-DDE, and HCB. PMID:25863595

  2. The Relationship between the Blood Level of Persistent Organic Pollutants and Common Gastrointestinal Symptoms

    PubMed Central

    Kim, Hyo-Min; Ko, Hae Jin; Lee, Seon-Hwa; Lee, Yu-Mi

    2016-01-01

    Background Persistent organic pollutants (POPs) are toxic materials that cannot be broken down naturally and that easily accumulate in the body. Although several studies have attempted to reveal the effects of POPs on the endocrine and nervous system and on cancer, few studies focus on the relationship between low-dose POPs and public health. We attempted to find a relationship between the level of POPs and common gastrointestinal symptoms, including abdominal discomfort, diarrhea, and constipation. Methods We recruited 121 subjects who visited Kyungpook National University Hospital for a health screening. Plasma concentrations were evaluated for 40 kinds of POPs including 17 types of polychlorinated biphenyls and 23 types of organochlorine pesticides. Furthermore, the Korean version of the Rome III criteria was used to identify gastrointestinal symptoms. Results Our results showed that abdominal discomfort had an inverse relationship with several polychlorinated biphenyls. Moreover, an inverted U-shaped relationship was observed between abdominal discomfort and several other organochlorine pesticides including p,p'-dichlorodiphenyldichloroethane and p,p'-dichlorodiphenyltrichloroethane, and the effects of these pesticides on abdominal discomfort were similar to that of organochlorine pesticides on obesity and metabolic syndrome. Conclusion Our results suggest that mild and unspecified gastrointestinal symptoms with no clear cause could be related to POPs levels. PMID:27688859

  3. The Relationship between the Blood Level of Persistent Organic Pollutants and Common Gastrointestinal Symptoms

    PubMed Central

    Kim, Hyo-Min; Ko, Hae Jin; Lee, Seon-Hwa; Lee, Yu-Mi

    2016-01-01

    Background Persistent organic pollutants (POPs) are toxic materials that cannot be broken down naturally and that easily accumulate in the body. Although several studies have attempted to reveal the effects of POPs on the endocrine and nervous system and on cancer, few studies focus on the relationship between low-dose POPs and public health. We attempted to find a relationship between the level of POPs and common gastrointestinal symptoms, including abdominal discomfort, diarrhea, and constipation. Methods We recruited 121 subjects who visited Kyungpook National University Hospital for a health screening. Plasma concentrations were evaluated for 40 kinds of POPs including 17 types of polychlorinated biphenyls and 23 types of organochlorine pesticides. Furthermore, the Korean version of the Rome III criteria was used to identify gastrointestinal symptoms. Results Our results showed that abdominal discomfort had an inverse relationship with several polychlorinated biphenyls. Moreover, an inverted U-shaped relationship was observed between abdominal discomfort and several other organochlorine pesticides including p,p'-dichlorodiphenyldichloroethane and p,p'-dichlorodiphenyltrichloroethane, and the effects of these pesticides on abdominal discomfort were similar to that of organochlorine pesticides on obesity and metabolic syndrome. Conclusion Our results suggest that mild and unspecified gastrointestinal symptoms with no clear cause could be related to POPs levels.

  4. Persistent elevation of CA 19-9 levels in a patient with an extended retroperitoneal dermoid.

    PubMed

    Micke, O; Schafer, U; Willich, N

    1999-01-01

    CA 19-9 has been established as sensitive tumor marker in a variety of malignant diseases, especially in carcinomas of the exocrine pancreas. The specificity of CA 19-9 is limited by many benign diseases causing abnormal values. A case of a patient with a retroperitoneal dermoid showing high serum levels of CA 19-9 will be described. The patient suffered from a large retroperitoneal mass (7 x 6 x 9 cm). A CT-guided fine needle biopsy of the tumor was performed and the histology was compatible with a benign dermoid. The CT-scans of the abdomen showed also the typical features of a dermoid. Tumor markers and lab counts stayed in the normal range except CA 19-9, which was constantly elevated with value between 131 and 329 U/ml. A benign or malignant disorder was excluded. An immunoscintigraphy and a SPECT with a I-131-labeled monoclonal antibody against CA 19-9 revealed the retroperitoneal mass as the source of the CA 19-9 elevation. This is the first case described in English scientific literature of a retroperitoneal dermoid (benign teratoma) as a source of a persistently elevated level of CA 19-9.

  5. Low-level viremia persists for at least 7 years in patients on suppressive antiretroviral therapy.

    PubMed

    Palmer, Sarah; Maldarelli, Frank; Wiegand, Ann; Bernstein, Barry; Hanna, George J; Brun, Scott C; Kempf, Dale J; Mellors, John W; Coffin, John M; King, Martin S

    2008-03-11

    Residual viremia can be detected in most HIV-1-infected patients on antiretroviral therapy despite suppression of plasma RNA to <50 copies per ml, but the source and duration of this viremia is currently unknown. Therefore, we analyzed longitudinal plasma samples from 40 patients enrolled in the Abbott M97-720 trial at baseline (pretherapy) and weeks 60 to 384 by using an HIV-1 RNA assay with single-copy sensitivity. All patients were on therapy (lopinavir/ritonavir, stavudine, and lamivudine) with plasma HIV RNA <50 copies per ml by week 96 of the study and thereafter. Single-copy assay results revealed that 77% of the patient samples had detectable low-level viremia (>/=1 copy per ml), and all patients had at least one sample with detectable viremia. A nonlinear mixed effects model revealed a biphasic decline in plasma RNA levels occurring over weeks 60 to 384: an initial phase of decay with a half-life of 39 weeks and a subsequent phase with no perceptible decay. The level of pretherapy viremia extrapolated for each phase of decay was significantly correlated with total baseline viremia for each patient (R(2) = 0.27, P = 0.001 and R(2) = 0.19, P < 0.005, respectively), supporting a biological link between the extent of overall baseline viral infection and the infection of long-lived reservoirs. These data suggest that low-level persistent viremia appears to arise from at least two cell compartments, one in which viral production decays over time and a second in which viral production remains stable for at least 7 years. PMID:18332425

  6. Low-level viremia persists for at least 7 years in patients on suppressive antiretroviral therapy

    PubMed Central

    Palmer, Sarah; Maldarelli, Frank; Wiegand, Ann; Bernstein, Barry; Hanna, George J.; Brun, Scott C.; Kempf, Dale J.; Mellors, John W.; Coffin, John M.; King, Martin S.

    2008-01-01

    Residual viremia can be detected in most HIV-1-infected patients on antiretroviral therapy despite suppression of plasma RNA to <50 copies per ml, but the source and duration of this viremia is currently unknown. Therefore, we analyzed longitudinal plasma samples from 40 patients enrolled in the Abbott M97-720 trial at baseline (pretherapy) and weeks 60 to 384 by using an HIV-1 RNA assay with single-copy sensitivity. All patients were on therapy (lopinavir/ritonavir, stavudine, and lamivudine) with plasma HIV RNA <50 copies per ml by week 96 of the study and thereafter. Single-copy assay results revealed that 77% of the patient samples had detectable low-level viremia (≥1 copy per ml), and all patients had at least one sample with detectable viremia. A nonlinear mixed effects model revealed a biphasic decline in plasma RNA levels occurring over weeks 60 to 384: an initial phase of decay with a half-life of 39 weeks and a subsequent phase with no perceptible decay. The level of pretherapy viremia extrapolated for each phase of decay was significantly correlated with total baseline viremia for each patient (R2 = 0.27, P = 0.001 and R2 = 0.19, P < 0.005, respectively), supporting a biological link between the extent of overall baseline viral infection and the infection of long-lived reservoirs. These data suggest that low-level persistent viremia appears to arise from at least two cell compartments, one in which viral production decays over time and a second in which viral production remains stable for at least 7 years. PMID:18332425

  7. LA35 Poultry Fecal Marker Persistence Is Correlated with That of Indicators and Pathogens in Environmental Waters

    PubMed Central

    Nayak, Bina; Weidhaas, Jennifer

    2015-01-01

    Disposal of fecally contaminated poultry litter by land application can deliver pathogens and fecal indicator bacteria (FIB) into receiving waters via runoff. While water quality is regulated by FIB enumeration, FIB testing provides inadequate information about contamination source and health risk. This microbial source tracking (MST) study compared the persistence of the Brevibacterium sp. strain LA35 16S rRNA gene (marker) for poultry litter with that of pathogens and FIB under outdoor, environmentally relevant conditions in freshwater, marine water, and sediments over 7 days. Salmonella enterica, Campylobacter jejuni, Campylobacter coli, Bacteroidales, and LA35 were enumerated by quantitative PCR (qPCR), and Enterococcus spp. and E. coli were quantified by culture and qPCR. Unlike the other bacteria, C. jejuni was not detectable after 48 h. Bacterial levels in the water column consistently declined over time and were highly correlated among species. Survival in sediments ranged from a slow decrease over time to growth, particularly in marine microcosms and for Bacteroidales. S. enterica also grew in marine sediments. Linear decay rates in water (k) ranged from −0.17 day−1 for LA35 to −3.12 day−1 for C. coli. LA35 levels correlated well with those of other bacteria in the water column but not in sediments. These observations suggest that, particularly in the water column, the fate of LA35 in aquatic environments is similar to that of FIB, C. coli, and Salmonella, supporting the hypothesis that the LA35 marker gene can be a useful tool for evaluating the impact of poultry litter on water quality and human health risk. PMID:25934617

  8. LA35 Poultry Fecal Marker Persistence Is Correlated with That of Indicators and Pathogens in Environmental Waters.

    PubMed

    Nayak, Bina; Weidhaas, Jennifer; Harwood, Valerie J

    2015-07-01

    Disposal of fecally contaminated poultry litter by land application can deliver pathogens and fecal indicator bacteria (FIB) into receiving waters via runoff. While water quality is regulated by FIB enumeration, FIB testing provides inadequate information about contamination source and health risk. This microbial source tracking (MST) study compared the persistence of the Brevibacterium sp. strain LA35 16S rRNA gene (marker) for poultry litter with that of pathogens and FIB under outdoor, environmentally relevant conditions in freshwater, marine water, and sediments over 7 days. Salmonella enterica, Campylobacter jejuni, Campylobacter coli, Bacteroidales, and LA35 were enumerated by quantitative PCR (qPCR), and Enterococcus spp. and E. coli were quantified by culture and qPCR. Unlike the other bacteria, C. jejuni was not detectable after 48 h. Bacterial levels in the water column consistently declined over time and were highly correlated among species. Survival in sediments ranged from a slow decrease over time to growth, particularly in marine microcosms and for Bacteroidales. S. enterica also grew in marine sediments. Linear decay rates in water (k) ranged from -0.17 day(-1) for LA35 to -3.12 day(-1) for C. coli. LA35 levels correlated well with those of other bacteria in the water column but not in sediments. These observations suggest that, particularly in the water column, the fate of LA35 in aquatic environments is similar to that of FIB, C. coli, and Salmonella, supporting the hypothesis that the LA35 marker gene can be a useful tool for evaluating the impact of poultry litter on water quality and human health risk. PMID:25934617

  9. Childhood Predictors of Desistance and Level of Persistence in Offending in Early Onset Offenders

    ERIC Educational Resources Information Center

    van Domburgh, L.; Loeber, R.; Bezemer, D.; Stallings, R.; Stouthamer-Loeber, M.

    2009-01-01

    Childhood predictors of adolescent offending careers were studied in 310 boys from the longitudinal Pittsburgh Youth Study who started offending prior to age 12. Three main groups were distinguished: serious persisters (n = 95), moderately serious persisters (n = 117), desisters (n = 63), and an intermittent group (n = 35). Group membership was…

  10. Persistent disparities in stratospheric water vapor measurements drive large uncertainties in the radiative forcing by lower stratospheric water vapor

    NASA Astrophysics Data System (ADS)

    Hurst, D. F.; Rosenlof, K. H.; Portmann, R. W.; Voemel, H.; Schiller, C.; Smith, J. B.; Thornberry, T. D.; Rollins, A. W.; Hall, E.; Jordan, A.; Oltmans, S. J.

    2011-12-01

    Lower stratospheric water vapor is a powerful attenuator of outgoing long wave radiation, hence its strong influence on the Earth's radiation budget. The radiative forcing by lower stratospheric water vapor is, however, quite uncertain because of significant disparities in lower stratospheric water vapor measurements by different instruments. Specifically, measurement discrepancies of 0.5 to 2 ppmv H2O (15 to 60%) between several well-established aircraft- and balloon-borne instruments have now persisted for almost two decades. The Mid-latitude Airborne Cirrus Properties Experiment (MACPEX) in April 2011 provided not only a fresh opportunity to reexamine and reevaluate these persistent measurement discrepancies, but also to compare water vapor measurements by additional aircraft-based instrumentation. Here we compare the in situ measurements of lower stratospheric water vapor by five different instruments during MACPEX. Three of these instruments (Harvard water, FISH, and NOAA CIMS) were aboard the NASA WB-57 aircraft, while two (CFH and NOAA FPH) were launched on balloons. Substantial efforts were made to coordinate aircraft and balloon measurements in space and time, such that the aircraft would reach maximum altitude en route to the balloon rendezvous point, then both aircraft and balloon would descend together. Lower stratospheric water vapor measurements during MACPEX generally fall into two groups: CFH, NOAA FPH and FISH are in good agreement, while Harvard water and NOAA CIMS agree with each other but are significantly different than the other group. Differences between the two groups range from 0.5 to 1.0 ppmv (15 to 30%), with Harvard and NOAA CIMS mixing ratios consistently higher. Though these differences seem relatively large, they are smaller than some previously observed differences between the FPH/CFH and Harvard water. For example, Harvard stratospheric water vapor measurements during the 1993 CEPEX and 2006 CR-AVE campaigns were 1.5 and 2 ppmv

  11. Modeling Tidal Water Levels for Canadian Coastal and Offshore waters

    NASA Astrophysics Data System (ADS)

    Robin, C. M. I.; MacAulay, P.; Nudds, S.; Godin, A.; de Lange Boom, B.; Bartlett, J.; Maltais, L.; Herron, T.; Craymer, M. R.; Veronneau, M.; Fadaie, K.

    2014-12-01

    IIn 2010, the Canadian Hydrographic Service initiated the Continuous Vertical Datum for Canadian Waters (CVDCW) project, the aim of which is to connect tidal water level datums (high and low water levels, chart datum, etc.) to a national geodetic reference frame over all Canadian tidal waters. Currently, water level datums are tied to a geodetic reference frame at approximately 400 tide stations which have been surveyed with GPS, whereas water levels vary significantly in space even a short distance away from tide stations. The CVDCW captures the relevant spatial variability between stations and offshore by integrating ocean models, gauge data (water level analyses and/or GPS observations), sea level trends, satellite altimetry, and a geoid model. The CVDCW will enable the use of Global Navigation Satellite System technologies (primarily GPS) for hydrographers and navigators. It will also be important for other users including oceanographers, environmental and climate scientists, surveyors and engineers. For instance, it will allow easier integration of hydrographic and terrestrial data, provide a baseline for storm surge modeling and climate change adaptation, and aid with practical issues such as sovereignty and the definition of the coastline. Once high and low water surfaces are complete, they will define a large portion of the vertical link between land and ocean, helping to delineate flooding thresholds and inter-tidal ecosystem zones and boundaries. Here we present an overview of the methodology using a set of prototype model results, and will outline features of interest for studies in coastal stability, climate change adaptation, and sea level change.

  12. Persistence of Microbial Contamination on Transvaginal Ultrasound Probes despite Low-Level Disinfection Procedure

    PubMed Central

    M'Zali, Fatima; Bounizra, Carole; Leroy, Sandrine; Mekki, Yahia; Quentin-Noury, Claudine; Kann, Michael

    2014-01-01

    Aim of the Study In many countries, Low Level Disinfection (LLD) of covered transvaginal ultrasound probes is recommended between patients' examinations. The aim of this study was to evaluate the antimicrobial efficacy of LLD under routine conditions on a range of microorganisms. Materials and Methods Samples were taken over a six month period in a private French Radiology Center. 300 specimens derived from endovaginal ultrasound probes were analyzed after disinfection of the probe with wipes impregnated with a quaternary ammonium compound and chlorhexidine. Human papillomavirus (HPV) was sought in the first set of s100 samples, Chlamydia trachomatis and mycoplasmas were searched in the second set of 100 samples, bacteria and fungi in the third 100 set samples. HPV, C. trachomatis and mycoplasmas were detected by PCR amplification. PCR positive samples were subjected to a nuclease treatment before an additional PCR assay to assess the likely viable microorganisms. Bacteria and fungi were investigated by conventional methods. Results A substantial persistence of microorganisms was observed on the disinfected probes: HPV DNA was found on 13% of the samples and 7% in nuclease-resistant form. C. trachomatis DNA was detected on 20% of the probes by primary PCR but only 2% after nuclease treatment, while mycoplasma DNA was amplified in 8% and 4%, respectively. Commensal and/or environmental bacterial flora was present on 86% of the probes, occasionally in mixed culture, and at various levels (10->3000 CFU/probe); Staphylococcus aureus was cultured from 4% of the probes (10-560 CFU/probe). No fungi were isolated. Conclusion Our findings raise concerns about the efficacy of impregnated towels as a sole mean for disinfection of ultrasound probes. Although the ultrasound probes are used with disposable covers, our results highlight the potential risk of cross contamination between patients during ultrasound examination and emphasize the need for reviewing the disinfection

  13. The persistence of the water budget myth and its relationship to sustainability

    USGS Publications Warehouse

    Devlin, J.F.; Sophocleous, M.

    2005-01-01

    Sustainability and sustainable pumping are two different concepts that are often used interchangeably. The latter term refers to a pumping rate that can be maintained indefinitely without mining an aquifer, whereas the former term is broader and concerns such issues as ecology and water quality, among others, in addition to sustainable pumping. Another important difference between the two concepts is that recharge can be very important to consider when assessing sustainability, but is not necessary to estimate sustainable pumping rates. Confusion over this distinction is made worse by the Water Budget Myth, which comprises the mistaken yet persistent ideas that (1) sustainable pumping rates cannot exceed virgin recharge rates in aquifers, and (2) that virgin recharge rates must therefore be known to estimate sustainable pumping rates. Analysis of the water balance equation shows the special circumstances that must apply for the Water Budget Myth to be true. However, due to the effects recharge is likely to have on water quality, ecology, socioeconomic factors, and, under certain circumstances, its requirement for numerical modeling, it remains important in assessments of sustainability. ?? Springer-Verlag 2004.

  14. Duration of Ebola virus RNA persistence in semen of survivors: population-level estimates and projections.

    PubMed

    Eggo, Rosalind M; Watson, Conall H; Camacho, Anton; Kucharski, Adam J; Funk, Sebastian; Edmunds, W John

    2015-01-01

    Ebola virus can persist in semen after recovery, potentially for months, which may impact the duration of enhanced surveillance required after interruption of transmission. We combined recent data on viral RNA persistence with weekly disease incidence to estimate the current number of semen-positive men in affected West African countries. We find the number is low, and since few reported sexual transmission events have occurred, the future risk is also likely low, although sexual health promotion remains critical. PMID:26676163

  15. Persistence of pharmaceutical compounds and other organic wastewater contaminants in a conventional drinking-water-treatment plant.

    PubMed

    Stackelberg, Paul E; Furlong, Edward T; Meyer, Michael T; Zaugg, Steven D; Henderson, Alden K; Reissman, Dori B

    2004-08-15

    In a study conducted by the US Geological Survey and the Centers for Disease Control and Prevention, 24 water samples were collected at selected locations within a drinking-water-treatment (DWT) facility and from the two streams that serve the facility to evaluate the potential for wastewater-related organic contaminants to survive a conventional treatment process and persist in potable-water supplies. Stream-water samples as well as samples of raw, settled, filtered, and finished water were collected during low-flow conditions, when the discharge of effluent from upstream municipal sewage-treatment plants accounted for 37-67% of flow in stream 1 and 10-20% of flow in stream 2. Each sample was analyzed for 106 organic wastewater-related contaminants (OWCs) that represent a diverse group of extensively used chemicals. Forty OWCs were detected in one or more samples of stream water or raw-water supplies in the treatment plant; 34 were detected in more than 10% of these samples. Several of these compounds also were frequently detected in samples of finished water; these compounds include selected prescription and non-prescription drugs and their metabolites, fragrance compounds, flame retardants and plasticizers, cosmetic compounds, and a solvent. The detection of these compounds suggests that they resist removal through conventional water-treatment processes. Other compounds that also were frequently detected in samples of stream water and raw-water supplies were not detected in samples of finished water; these include selected prescription and non-prescription drugs and their metabolites, disinfectants, detergent metabolites, and plant and animal steroids. The non-detection of these compounds indicates that their concentrations are reduced to levels less than analytical detection limits or that they are transformed to degradates through conventional DWT processes. Concentrations of OWCs detected in finished water generally were low and did not exceed Federal

  16. Persistence of pharmaceutical compounds and other organic wastewater contaminants in a conventional drinking-water-treatment plant

    USGS Publications Warehouse

    Stackelberg, P.E.; Furlong, E.T.; Meyer, M.T.; Zaugg, S.D.; Henderson, A.K.; Reissman, D.B.

    2004-01-01

    In a study conducted by the US Geological Survey and the Centers for Disease Control and Prevention, 24 water samples were collected at selected locations within a drinking-water-treatment (DWT) facility and from the two streams that serve the facility to evaluate the potential for wastewater-related organic contaminants to survive a conventional treatment process and persist in potable-water supplies. Stream-water samples as well as samples of raw, settled, filtered, and finished water were collected during low-flow conditions, when the discharge of effluent from upstream municipal sewage-treatment plants accounted for 37-67% of flow in stream 1 and 10-20% of flow in stream 2. Each sample was analyzed for 106 organic wastewater-related contaminants (OWCs) that represent a diverse group of extensively used chemicals. Forty OWCs were detected in one or more samples of stream water or raw-water supplies in the treatment plant; 34 were detected in more than 10% of these samples. Several of these compounds also were frequently detected in samples of finished water; these compounds include selected prescription and non-prescription drugs and their metabolites, fragrance compounds, flame retardants and plasticizers, cosmetic compounds, and a solvent. The detection of these compounds suggests that they resist removal through conventional water-treatment processes. Other compounds that also were frequently detected in samples of stream water and raw-water supplies were not detected in samples of finished water; these include selected prescription and non-prescription drugs and their metabolites, disinfectants, detergent metabolites, and plant and animal steroids. The non-detection of these compounds indicates that their concentrations are reduced to levels less than analytical detection limits or that they are transformed to degradates through conventional DWT processes. Concentrations of OWCs detected in finished water generally were low and did not exceed Federal

  17. Persistence of Indicator and Pathogenic Microorganisms in Broccoli following Manure Spreading and Irrigation with Fecally Contaminated Water: Field Experiment.

    PubMed

    Généreux, Mylène; Breton, Marie Jo; Fairbrother, John Morris; Fravalo, Philippe; Côté, Caroline

    2015-10-01

    In 2011 and 2012, trials consisting of experimental plots were carried out to evaluate the presence of pathogenic (Listeria monocytogenes, Salmonella) and prevalence of indicator (Escherichia coli) microorganisms in broccoli fertilized with liquid hog manure or mineral fertilizers and irrigated zero, one, or two times with E. coli-contaminated water. In 2011, results showed that E. coli contamination in broccoli heads was affected by the interval between irrigation and sampling (P = 0.0236), with a significant decrease between the first and third day following irrigation (P = 0.0064). In 2012, irrigation frequency significantly increased E. coli prevalence in broccoli samples (P = 0.0499). In 2012, E. coli counts in the soil were significantly influenced by the type of fertilizer applied, as plots receiving liquid hog manure showed higher bacterial counts (P = 0.0006). L. monocytogenes was recovered in one broccoli sample, but geno-serogrouping differentiated the isolate from those recovered in manure and irrigation water. The L. monocytogenes serogroup IIA, pulsotype 188 strain was found in six soil samples and in irrigation water applied 5 days before soil sampling. This study highlights the link between E. coli levels in irrigation water, irrigation frequency, and interval between irrigation and harvest on produce contamination. It also demonstrates that L. monocytogenes introduced into the soil following irrigation can persist for up to 5 days.

  18. The levels and composition of persistent organic pollutants in alluvial agriculture soils affected by flooding.

    PubMed

    Maliszewska-Kordybach, Barbara; Smreczak, Bozena; Klimkowicz-Pawlas, Agnieszka

    2013-12-01

    The concentrations and composition of persistent organic pollutants (POPs) were determined in alluvial soils subjected to heavy flooding in a rural region of Poland. Soil samples (n = 30) were collected from the upper soil layer from a 70-km(2) area. Chemical determinations included basic physicochemical properties and the contents of polychlorinated biphenyls (PCBs), hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and polycyclic aromatic hydrocarbons (PAHs, 16 compounds). The median concentrations of Σ7PCB (PCB28 + PCB52 + PCB101 + PCB118 + PCB138 + PCB153 + PCB180), Σ3HCH (α-HCH + β-HCH + γ-HCH) and Σ3pp'(DDT + DDE + DDD) were 1.60 ± 1.03, 0.22 ± 0.13 and 25.18 ± 82.70 μg kg(-1), respectively. The median concentrations of the most abundant PAHs, phenanthrene, fluoranthene, pyrene, benzo[b]fluoranthene and benzo[a]pyrene were 50 ± 37, 38 ± 27, 29 ± 30, 45 ± 36 and 24 ± 22 μg kg(-1), respectively. Compared with elsewhere in the world, the overall level of contamination with POPs was low and similar to the levels in agricultural soils from neighbouring countries, except for benzo[a]pyrene and DDT. There was no evidence that flooding affected the levels of POPs in the studied soils. The patterns observed for PAHs and PCBs indicate that atmospheric deposition is the most important long-term source of these contaminants. DDTs were the dominant organochlorine pesticides (up to 99%), and the contribution of the parent pp' isomer was up to 50 % of the ΣDDT, which indicates the advantage of aged contamination. A high pp'DDE/pp'DDD ratio suggests the prevalence of aerobic transformations of parent DDT. Dominance of the γ isomer in the HCHs implies historical use of lindane in the area. The effect of soil properties on the POP concentrations was rather weak, although statistically significant links with the content of the <0.02-mm fraction, Ctotal or Ntotal were observed for some individual compounds in the PCB group.

  19. Are Persistent Early Onset Child Conduct Problems Predicted by the Trajectories and Initial Levels of Discipline Practices?

    ERIC Educational Resources Information Center

    Lorber, Michael F.; Slep, Amy M. Smith

    2015-01-01

    In the present investigation we focused on 2 broad sets of questions: Do parental overreactivity, laxness, and corporal punishment show evidence of normative change in early to middle childhood? Are persistently elevated child conduct problems (CPs) associated with deviations from normative changes in, as well as high initial levels of, discipline…

  20. A review of surface-water sediment fractions and their interactions with persistent manmade organic compounds

    USGS Publications Warehouse

    Witkowski, P.J.; Smith, J.A.; Fusillo, T.V.; Chiou, C.T.

    1987-01-01

    This paper reviews the suspended and surficial sediment fractions and their interactions with manmade organic compounds. The objective of this review is to isolate and describe those contaminant and sediment properties that contribute to the persistence of organic compounds in surface-water systems. Most persistent, nonionic organic contaminants, such as the chlorinated insecticides and polychlorinated biphenyls (PCBs), are characterized by low water solubilities and high octanol-water partition coefficients. Consequently, sorptive interactions are the primary transformation processes that control their environmental behavior. For nonionic organic compounds, sorption is primarily attributed to the partitioning of an organic contaminant between a water phase and an organic phase. Partitioning processes play a central role in the uptake and release of contaminants by sediment organic matter and in the bioconcentration of contaminants by aquatic organisms. Chemically isolated sediment fractions show that organic matter is the primary determinant of the sorptive capacity exhibited by sediment. Humic substances, as dissolved organic matter, contribute a number of functions to the processes cycling organic contaminants. They alter the rate of transformation of contaminants, enhance apparent water solubility, and increase the carrying capacity of the water column beyond the solubility limits of the contaminant. As a component of sediment particles, humic substances, through sorptive interactions, serve as vectors for the hydrodynamic transport of organic contaminants. The capabilities of the humic substances stem in part from their polyfunctional chemical composition and also from their ability to exist in solution as dissolved species, flocculated aggregates, surface coatings, and colloidal organomineral and organometal complexes. The transport properties of manmade organic compounds have been investigated by field studies and laboratory experiments that examine the

  1. Hydro static water level systems at Fermilab

    SciTech Connect

    Volk, J.T.; Guerra, J.A.; Hansen, S.U.; Kiper, T.E.; Jostlein, H.; Shiltsev, V.; Chupyra, A.; Kondaurov, M.; Singatulin, S.

    2006-09-01

    Several Hydrostatic Water Leveling systems (HLS) are in use at Fermilab. Three systems are used to monitor quadrupoles in the Tevatron and two systems are used to monitor ground motion for potential sites for the International Linear Collider (ILC). All systems use capacitive sensors to determine the water level of water in a pool. These pools are connected with tubing so that relative vertical shifts between sensors can be determined. There are low beta quadrupoles at the B0 and D0 interaction regions of Tevatron accelerator. These quadrupoles use BINP designed and built sensors and have a resolution of 1 micron. All regular lattice superconducting quadrupoles (a total of 204) in the Tevatron use a Fermilab designed system and have a resolution of 6 microns. Data on quadrupole motion due to quenches, changes in temperature will be presented. In addition data for ground motion for ILC studies caused by natural and cultural factors will be presented.

  2. Significance and clinical management of persistent low-level viremia and very-low-level viremia in HIV-1-infected patients.

    PubMed

    Ryscavage, Patrick; Kelly, Sean; Li, Jonathan Z; Harrigan, P Richard; Taiwo, Babafemi

    2014-07-01

    A goal of HIV therapy is to sustain suppression of the plasma viral load below the detection limits of clinical assays. However, widely followed treatment guidelines diverge in their interpretation and recommended management of persistent viremia of low magnitude, reflecting the limited evidence base for this common clinical finding. Here, we review the incidence, risk factors, and potential consequences of low-level HIV viremia (LLV; defined in this review as a viremia level of 50 to 500 copies/ml) and very-low-level viremia (VLLV; defined as a viremia level of <50 copies/ml detected by clinical assays that have quantification cutoffs of <50 copies/ml). Using this framework, we discuss practical issues related to the diagnosis and management of patients experiencing persistent LLV and VLLV. Compared to viral suppression at <50 or 40 copies/ml, persistent LLV is associated with increased risk of antiretroviral drug resistance and overt virologic failure. Higher immune activation and HIV transmission may be additional undesirable consequences in this population. It is uncertain whether LLV of <200 copies/ml confers independent risks, as this level of viremia may reflect assay-dependent artifacts or biologically meaningful events during suppression. Resistance genotyping should be considered in patients with persistent LLV when feasible, and treatment should be modified if resistance is detected. There is a dearth of clinical evidence to guide management when genotyping is not feasible. Increased availability of genotypic assays for samples with viral loads of <400 copies/ml is needed.

  3. Surface Water-Groundwater Interactions as a Critical Component of Uranium Plume Persistence

    NASA Astrophysics Data System (ADS)

    Williams, K. H.; Christensen, J. N.; Hobson, C.

    2015-12-01

    Residual contamination of soils, sediments and groundwater by uranium milling operations presents a lingering problem at former mill sites throughout the upper Colorado River Basin in the western USA. Remedial strategies predicated upon natural flushing by low uranium recharge waters have frequently failed to achieve target concentrations set by national and state regulators. Flushing times of tens of years have often yielded negligible decreases in groundwater uranium concentrations, with extrapolated trends suggesting multiple decades or longer may be required to achieve regulatory goals. The U.S. Department of Energy's Rifle, Colorado field site serves as a natural laboratory for investigating the underlying causes for uranium plume persistence, with recent studies there highlighting the important role that surface water-groundwater interactions play in sustaining uranium delivery to the aquifer. Annual snowmelt-driven increases in Colorado River discharge induce 1-2 m excursions in groundwater elevation at the Rifle site, which enables residual tailings-contaminated materials (so-called Supplemental Standards) to become hydrologically connected to the aquifer for short periods of time during peak discharge. The episodic contact between shallow groundwater and residual contamination leads to abrupt 20-fold increases in groundwater uranium concentration, which serve to seasonally replenish the plume given the location of the Supplemental Standards along the upgradient edge of the aquifer. Uranium isotope composition changes abruptly as uranium concentrations increase reflecting the contribution of a temporally distinct contaminant reservoir. The release of uranium serves to potentially replenish organic matter rich sediments located within the alluvial aquifer at downstream locations, which have been postulated to serve as a parallel contributor to plume persistence following the uptake, immobilization, and slow re-oxidation of uranium.

  4. Effect of turbidity on chlorination efficiency and bacterial persistence in drinking water.

    PubMed

    LeChevallier, M W; Evans, T M; Seidler, R J

    1981-07-01

    To define interrelationships between elevated turbidities and the efficiency of chlorination in drinking water, experiments were performed to measure bacterial survival, chlorine demand, and interference with microbiological determinations. Experiments were conducted on the surface water supplies for communities which practice chlorination as the only treatment. Therefore, the conclusions of this study apply only to such systems. Results indicated that disinfection efficiency (log10 of the decrease in coliform numbers) was negatively correlated with turbidity and was influenced by season, chlorine demand of the samples, and the initial coliform level. Total organic carbon was found to be associated with turbidity and was shown to interfere with maintenance of a free chlorine residual by creating a chlorine demand. Interference with coliform detection in turbid waters could be demonstrated by the recovery of typical coliforms from apparently negative filters. The incidence of coliform masking in the membrane filter technique was found to increase as the turbidity of the chlorinated samples increased. the magnitude of coliform masking in the membrane filter technique increased from less than 1 coliform per 100 ml in water samples of less than 5 nephelometric turbidity units to greater than 1 coliform per 100 ml in water samples of greater than 5 nephelometric turbidity units. Statistical models were developed to predict the impact of turbidity on drinking water quality. The results justify maximum contaminant levels for turbidity in water entering a distribution system as stated in the National Primary Drinking Water Regulations of the Safe Drinking Water Act. PMID:7259162

  5. Genes Indicative of Zoonotic and Swine Pathogens Are Persistent in Stream Water and Sediment following a Swine Manure Spill.

    PubMed

    Haack, Sheridan K; Duris, Joseph W; Kolpin, Dana W; Fogarty, Lisa R; Johnson, Heather E; Gibson, Kristen E; Focazio, Michael; Schwab, Kellogg J; Hubbard, Laura E; Foreman, William T

    2015-05-15

    Manure spills into streams are relatively frequent, but no studies have characterized stream contamination with zoonotic and veterinary pathogens, or fecal chemicals, following a spill. We tested stream water and sediment over 25 days and downstream for 7.6 km for the following: fecal indicator bacteria (FIB), the fecal indicator chemicals cholesterol and coprostanol, 20 genes for zoonotic and swine-specific bacterial pathogens by presence/absence PCR for viable cells, one swine-specific Escherichia coli toxin gene (STII gene) by quantitative PCR (qPCR), and nine human and animal viruses by qPCR or reverse transcription-qPCR. Twelve days postspill, and 4.2 km downstream, water concentrations of FIB, cholesterol, and coprostanol were 1 to 2 orders of magnitude greater than those detected before, or above, the spill, and genes indicating viable zoonotic or swine-infectious Escherichia coli were detected in water or sediment. STII gene levels increased from undetectable before or above the spill to 10(5) copies/100 ml of water 12 days postspill. Thirteen of 14 water (8/9 sediment) samples had viable STII-carrying cells postspill. Eighteen days postspill, porcine adenovirus and teschovirus were detected 5.6 km downstream. FIB concentrations (per gram [wet weight]) in sediment were greater than in water, and sediment was a continuous reservoir of genes and chemicals postspill. Constituent concentrations were much lower, and detections less frequent, in a runoff event (200 days postspill) following manure application, although the swine-associated STII and stx2e genes were detected. Manure spills are an underappreciated pathway for livestock-derived contaminants to enter streams, with persistent environmental outcomes and the potential for human and veterinary health consequences. PMID:25769829

  6. Genes Indicative of Zoonotic and Swine Pathogens Are Persistent in Stream Water and Sediment following a Swine Manure Spill

    PubMed Central

    Duris, Joseph W.; Kolpin, Dana W.; Fogarty, Lisa R.; Johnson, Heather E.; Gibson, Kristen E.; Focazio, Michael; Schwab, Kellogg J.; Hubbard, Laura E.; Foreman, William T.

    2015-01-01

    Manure spills into streams are relatively frequent, but no studies have characterized stream contamination with zoonotic and veterinary pathogens, or fecal chemicals, following a spill. We tested stream water and sediment over 25 days and downstream for 7.6 km for the following: fecal indicator bacteria (FIB), the fecal indicator chemicals cholesterol and coprostanol, 20 genes for zoonotic and swine-specific bacterial pathogens by presence/absence PCR for viable cells, one swine-specific Escherichia coli toxin gene (STII gene) by quantitative PCR (qPCR), and nine human and animal viruses by qPCR or reverse transcription-qPCR. Twelve days postspill, and 4.2 km downstream, water concentrations of FIB, cholesterol, and coprostanol were 1 to 2 orders of magnitude greater than those detected before, or above, the spill, and genes indicating viable zoonotic or swine-infectious Escherichia coli were detected in water or sediment. STII gene levels increased from undetectable before or above the spill to 105 copies/100 ml of water 12 days postspill. Thirteen of 14 water (8/9 sediment) samples had viable STII-carrying cells postspill. Eighteen days postspill, porcine adenovirus and teschovirus were detected 5.6 km downstream. FIB concentrations (per gram [wet weight]) in sediment were greater than in water, and sediment was a continuous reservoir of genes and chemicals postspill. Constituent concentrations were much lower, and detections less frequent, in a runoff event (200 days postspill) following manure application, although the swine-associated STII and stx2e genes were detected. Manure spills are an underappreciated pathway for livestock-derived contaminants to enter streams, with persistent environmental outcomes and the potential for human and veterinary health consequences. PMID:25769829

  7. Persistence and level of inoculated Salmonella Typhimurium in larval and adult darkling beetles.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alphitobius diaperinus is a common litter pest in broiler houses. Both adults and larvae are regularly ingested by broilers and could serve as a vector of Salmonella to the current and subsequent broiler flocks. The objectives of this study were to evaluate the persistence of a marker S. Typhimuri...

  8. Effects of landscape and patch-level attributes on regional population persistence

    EPA Science Inventory

    Habitat patch size and isolation are often described as the key habitat variables influencing population dynamics. Yet habitat quality may also play an important role in influencing the regional persistence of spatially structured populations as the value or density of resources ...

  9. The serum matrix metalloproteinase-9 level is an independent predictor of recurrence after ablation of persistent atrial fibrillation

    PubMed Central

    Wu, Gang; Wang, Shun; Cheng, Mian; Peng, Bin; Liang, Jingjun; Huang, He; Jiang, Xuejun; Zhang, Lizhi; Yang, Bo; Cha, Yongmei; Jiang, Hong; Huang, Congxin

    2016-01-01

    OBJECTIVES: This study investigated whether the serum matrix metalloproteinase-9 level is an independent predictor of recurrence after catheter ablation for persistent atrial fibrillation. METHODS: Fifty-eight consecutive patients with persistent atrial fibrillation were enrolled and underwent catheter ablation. The serum matrix metalloproteinase-9 level was detected before ablation and its relationship with recurrent arrhythmia was analyzed at the end of the follow-up. RESULTS: After a mean follow-up of 12.1±7.2 months, 21 (36.2%) patients had a recurrence of their arrhythmia after catheter ablation. At baseline, the matrix metalloproteinase-9 level was higher in the patients with recurrence than in the non-recurrent group (305.77±88.90 vs 234.41±93.36 ng/ml, respectively, p=0.006). A multivariate analysis showed that the matrix metalloproteinase-9 level was an independent predictor of arrhythmia recurrence, as was a history of atrial fibrillation and the diameter of the left atrium. CONCLUSION: The serum matrix metalloproteinase-9 level is an independent predictor of recurrent arrhythmia after catheter ablation in patients with persistent atrial fibrillation. PMID:27276393

  10. Spatial distribution of persistent organic pollutants in the surface water of River Brahmaputra and River Ganga in India.

    PubMed

    Chakraborty, Paromita; Sakthivel, S; Kumar, Bhupander; Kumar, Sanjay; Mishra, Meenu; Verma, V K; Gaur, Richa

    2014-01-01

    Persistent organic pollutants (POPs) like organochlorine pesticides (OCPs), polychlorinated biphenyles (PCBs) and polyaromatic hydrocarbons (PAHs) are discharged in surface water by various point and nonpoint sources thereby degrading the functioning of the ecosystem and threatening human health. Chlorinated pesticides such as Hexachlorocyclohexane (HCHs) and Dichlorodiphenyltrichloroethane (DDTs) are effective pest control chemicals, used in agriculture and public health activities (malaria eradication, etc.) in India for the past several decades and are still in use. POPs can cause endocrine disruption and food chain biomagnification because of their lipophilicity and environmental persistence. This study aims to assess the environmental occurrence and spatial distribution of OCPs, PAHs and PCBs in the surface water of River Brahmaputra and Ganga ending at the of the Bay of Bengal.The order of organochlorine pesticides is as: heptachlor>HCHs>DDTs>dieldrin>aldrin>endosulfan. Diamond Harbour and Bakkhali were the two places with elevated level of all individual HCH isomers compared to all other sites. β-Endosulfan and α-Endosulfan were high at Dibrugarh than other sampling sites. This is due to the ongoing use of Endosulfan in the tea estates in Assam especially the estates close to the town of Dibrugarh. p,p'-DDT and o,p'-DDT levels indicate the fresh input of DDT in all the sampling sites. Heptachlor has been observed in 57% of the total samples reported in the present study.These reasons may attribute to high deposition of pesticides in the surface water of Ganga and Brahmaputra.In addition the catchments area of the Ganga River is surrounded by agricultural lands so a relatively higher residue of pesticides was prevalent. Σ27 PCBs varied from BDL to 142 (Avg±SD, 3.96±6.71) ng L-1. PCB-18, PCB-52 & PCB-44 showed the highest concentration levels for all the sampling sites. PCB-126 was observed in samples taken from sites close to the city limit of Kolkata

  11. Spatial distribution of persistent organic pollutants in the surface water of River Brahmaputra and River Ganga in India.

    PubMed

    Chakraborty, Paromita; Sakthivel, S; Kumar, Bhupander; Kumar, Sanjay; Mishra, Meenu; Verma, V K; Gaur, Richa

    2014-01-01

    Persistent organic pollutants (POPs) like organochlorine pesticides (OCPs), polychlorinated biphenyles (PCBs) and polyaromatic hydrocarbons (PAHs) are discharged in surface water by various point and nonpoint sources thereby degrading the functioning of the ecosystem and threatening human health. Chlorinated pesticides such as Hexachlorocyclohexane (HCHs) and Dichlorodiphenyltrichloroethane (DDTs) are effective pest control chemicals, used in agriculture and public health activities (malaria eradication, etc.) in India for the past several decades and are still in use. POPs can cause endocrine disruption and food chain biomagnification because of their lipophilicity and environmental persistence. This study aims to assess the environmental occurrence and spatial distribution of OCPs, PAHs and PCBs in the surface water of River Brahmaputra and Ganga ending at the of the Bay of Bengal.The order of organochlorine pesticides is as: heptachlor>HCHs>DDTs>dieldrin>aldrin>endosulfan. Diamond Harbour and Bakkhali were the two places with elevated level of all individual HCH isomers compared to all other sites. β-Endosulfan and α-Endosulfan were high at Dibrugarh than other sampling sites. This is due to the ongoing use of Endosulfan in the tea estates in Assam especially the estates close to the town of Dibrugarh. p,p'-DDT and o,p'-DDT levels indicate the fresh input of DDT in all the sampling sites. Heptachlor has been observed in 57% of the total samples reported in the present study.These reasons may attribute to high deposition of pesticides in the surface water of Ganga and Brahmaputra.In addition the catchments area of the Ganga River is surrounded by agricultural lands so a relatively higher residue of pesticides was prevalent. Σ27 PCBs varied from BDL to 142 (Avg±SD, 3.96±6.71) ng L-1. PCB-18, PCB-52 & PCB-44 showed the highest concentration levels for all the sampling sites. PCB-126 was observed in samples taken from sites close to the city limit of Kolkata

  12. The role of the persistent fruit wall in seed water regulation in Raphanus raphanistrum (Brassicaceae)

    PubMed Central

    Cousens, Roger D.; Young, Kenneth R.; Tadayyon, Ali

    2010-01-01

    Background and Aims Dry fruits remain around the seeds at dispersal in a number of species, especially the Brassicaceae. Explanations for this vary, but usually involve mechanisms of innate dormancy. We speculate that, instead, a persistent fruit may give additional protection through control of dehydration, to species growing in arid or Mediterranean environments where water is sporadic. Methods X-rays and weight measurements were used to determine the extent to which Raphanus raphanistrum seeds within mature fruits imbibe water, and germination tests determined the roles of the fruit and seed coat in seed dormancy. Rates of water uptake and desiccation, and seedling emergence were compared with and without the fruit. Finally, germinability of seeds extracted from fruits was determined after various periods of moist conditions followed by a range of dry conditions. Key Results Most seeds rapidly take up water within the fruit, but they do not fully imbibe when compared with naked seeds. The seed coat is more important than the dry fruit wall in maintaining seed dormancy. The presence of a dry fruit slows emergence from the soil by up to 6–8 weeks. The fruit slows the rate of desiccation of the seed to a limited extent. The presence of the fruit for a few days during imbibition somehow primes more seeds to germinate than if the fruit is absent; longer moist periods within the pod appear to induce dormancy. Conclusions The fruit certainly modifies the seed environment as external conditions change between wet and dry, but not to a great extent. The major role seems to be: (a) the physical restriction of imbibition and germination; and (b) the release and then re-imposition of dormancy within the seed. The ecological significance of the results requires more research under field conditions. PMID:19889801

  13. GNSS-Reflectometry based water level monitoring

    NASA Astrophysics Data System (ADS)

    Beckheinrich, Jamila; Schön, Steffen; Beyerle, Georg; Apel, Heiko; Semmling, Maximilian; Wickert, Jens

    2013-04-01

    Due to climate changing conditions severe changes in the Mekong delta in Vietnam have been recorded in the last years. The goal of the German Vietnamese WISDOM (Water-related Information system for the Sustainable Development Of the Mekong Delta) project is to build an information system to support and assist the decision makers, planners and authorities for an optimized water and land management. One of WISDOM's tasks is the flood monitoring of the Mekong delta. Earth reflected L-band signals from the Global Navigation Satellite System show a high reflectivity on water and ice surfaces or on wet soil so that GNSS-Reflectometry (GNSS-R) could contribute to monitor the water level in the main streams of the Mekong delta complementary to already existing monitoring networks. In principle, two different GNSS-R methods exist: the code- and the phase-based one. As the latter being more accurate, a new generation of GORS (GNSS Occultation, Reflectometry and Scatterometry) JAVAD DELTA GNSS receiver has been developed with the aim to extract precise phase observations. In a two week lasting measurement campaign, the receiver has been tested and several reflection events at the 150-200 m wide Can Tho river in Vietnam have been recorded. To analyze the geometrical impact on the quantity and quality of the reflection traces two different antennas height were tested. To track separately the direct and the reflected signal, two antennas were used. To derive an average height of the water level, for a 15 min observation interval, a phase model has been developed. Combined with the coherent observations, the minimum slope has been calculated based on the Least- Squares method. As cycle slips and outliers will impair the results, a preprocessing of the data has been performed. A cycle slip detection strategy that allows for automatic detection, identification and correction is proposed. To identify outliers, the data snooping method developed by Baarda 1968 is used. In this

  14. Persistence and decontamination of surrogate radioisotopes in a model drinking water distribution system

    SciTech Connect

    Szabo, Jeffrey G.; Impellitteri, Christopher A.; Govindaswamy, Shekar; Hall, John S.

    2010-01-12

    Contamination of a model drinking water system with surrogate radioisotopes was examined with respect to persistence on and decontamination of infrastructure surfaces. Cesium and cobalt chloride salts were used as surrogates for cesium-137 and cobalt-60. Studies were conducted in biofilm annular reactors containing heavily corroded iron surfaces formed under shear and constantly submerged in drinking water. Cesium was not detected on the corroded iron surface after equilibration with 10 and 100 mg L{sup -1} solutions of cesium chloride, but cobalt was detected on corroded iron coupons at both initial concentrations. The amount of adhered cobalt decreased over the next six weeks, but was still present when monitoring stopped. X-ray absorption near-edge spectroscopy (XANES) showed that adhered cobalt was in the III oxidation state. The adsorbed cobalt was strongly resistant to decontamination by various physicochemical methods. Simulated flushing, use of free chlorine and dilute ammonia were found to be ineffective whereas use of aggressive methods like 14.5 M ammonia and 0.36 M sulfuric acid removed 37 and 92% of the sorbed cobalt, respectively.

  15. Brevetoxin persistence in sediments and seagrass epiphytes of east Florida coastal waters.

    PubMed

    Hitchcock, Gary L; Fourqurean, James W; Drake, Jeana L; Mead, Ralph N; Heil, Cynthia A

    2012-01-01

    A bloom of Karenia brevis Davis developed in September 2007 near Jacksonville, Florida and subsequently progressed south through east Florida coastal waters and the Atlantic Intracoastal Waterway (ICW). Maximum cell abundances exceeded 10(6) cells L(-1) through October in the northern ICW between Jacksonville and the Indian River Lagoon. The bloom progressed further south during November, and terminated in December 2007 at densities of 10(4) cells L(-1) in the ICW south of Jupiter Inlet, Florida. Brevetoxins were subsequently sampled in sediments and seagrass epiphytes in July and August 2008 in the ICW. Sediment brevetoxins occurred at concentrations of 11-15 ng PbTx-3 equivalents (g dry wt sediment)(-1) in three of five basins in the northern ICW during summer 2008. Seagrass beds occur south of the Mosquito Lagoon in the ICW. Brevetoxins were detected in six of the nine seagrass beds sampled between the Mosquito Lagoon and Jupiter Inlet at concentrations of 6-18 ng (g dry wt epiphytes)(-1). The highest brevetoxins concentrations were found in sediments near Patrick Air Force Base at 89 ng (g dry wt sediment)(-1). In general, brevetoxins occurred in either seagrass epiphytes or sediments. Blades of the resident seagrass species have a maximum life span of less than six months, so it is postulated that brevetoxins could be transferred between epibenthic communities of individual blades in seagrass beds. The occurrence of brevetoxins in east Florida coast sediments and seagrass epiphytes up to eight months after bloom termination supports observations from the Florida west coast that brevetoxins can persist in marine ecosystems in the absence of sustained blooms. Furthermore, our observations show that brevetoxins can persist in sediments where seagrass communities are absent.

  16. Levels and profiles of unintentionally produced persistent organic pollutants in surface soils from Shanxi province, China.

    PubMed

    Liu, G R; Cai, M W; Zheng, M H; Nie, Z Q; Liu, W B; Lv, P; Su, G J; Gao, L R; Xiao, K

    2011-05-01

    Six species of unintentionally produced persistent organic pollutions comprised of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, polychlorinated biphenyls, polychlorinated naphthalenes, hexachlorobenzene and pentachlorobenzene in soils collected from Shanxi province, China were determined. The sum toxic equivalent ranged from 0.14 to 2.20 with an average of 0.94 pg TEQ/g. Polychlorinated dibenzo-p-dioxins/furans contributed the most toxic proportion to the total toxic equivalent. CB-126 was the most toxic contributor to polychlorinated biphenyls. CN66/67 and CN73 are the dominant toxic congeners to polychlorinated naphthalenes. From the patterns, it was speculated that thermal related industries were possible sources of unintentionally produced persistent organic pollutions.

  17. Overall multi-media persistence as an indicator of potential for population-level intake of environmental contaminants

    SciTech Connect

    MacLeod, Matthew; McKone, Thomas E.

    2003-06-01

    Although it is intuitively apparent that population-level exposure to contaminants dispersed in the environment must related to the persistence of the contaminant, there has been little effort to formally quantify this link. In this paper we investigate the relationship between overall persistence in a multimedia environment and the population-level exposure as expressed by intake fraction (iF), which is the cumulative fraction of chemical emitted to the environment that is taken up by members of the population. We first confirm that for any given chemical contaminant and emission scenario the definition of iF implies that it is directly proportional to the overall multi-media persistence, P{sub OV}. We show that the proportionality constant has dimensions of time and represents the characteristic time for population intake (CTI) of the chemical from the environment. We then apply the CalTOX fate and exposure model to explore how P{sub OV} and CTI combine to determine the magnitude of iF. We find that CTI has a narrow range of possible values relative to P{sub OV} across multiple chemicals and emissions scenarios. We use data from the Canadian Environmental Protection Act Priority Substance List (PSL1) Assessments to show that exposure assessments based on empirical observation are consistent with interpretations from the model. The characteristic time for intake along different dominant exposure pathways is discussed. Results indicate that P{sub OV} derived from screening-level assessments of persistence, bioaccumulation potential, and toxicity (PBT) is a useful indicator of the potential for population-level exposure.

  18. Hydrostatic Water Level Systems At Homestake DUSEL

    NASA Astrophysics Data System (ADS)

    Stetler, L. D.; Volk, J. T.

    2009-12-01

    Two arrays of Fermilab-style hydrostatic water level sensors have been installed in the former Homestake gold mine in Lead, SD, the site of the new Deep Underground Science and Engineering Laboratory (DUSEL). Sensors were constructed at Fermilab from 8.5 cm diameter PVC pipe (housing) that was sealed on the ends and fit with a proximity sensor. The instrument have a height of 10 cm. Two ports in each sensor housing provide for connectivity, the upper port for air and the bottom port for water. Multiple instruments connected in series provide a precise water level and differences in readings between successive sensors provide for ground tilt to be resolved. Sensor resolution is 5 μm per count and has a range of approximately 1.25 cm. Data output from each sensor is relayed to a Fermilab-constructed readout card that also has temperature/relative humidity and barometric pressure sensors connected. All data are relayed out of the mine by fiber optic cable and can be recorded by Ethernet at remote locations. The current arrays have been installed on the 2000-ft level (610 m) and consist of six instruments in each array. Three sensors were placed in a N-S oriented drift and three in an E-W oriented drift. Using this orientation, it is anticipated that tilt direction may be resolved in addition to overall tilt magnitude. To date the data show passage of earth tides and frequency analysis has revealed five components to this signal, three associated with the semi-diurnal (~12.4 hr) and two with the diurnal (~24.9 hr) tides. Currently, installation methods are being analyzed between concrete pillar and rib-mounting using the existing setup on the 2000-ft level. Using these results, two additional arrays of Fermilab instruments will be installed on the 4550-ft and 4850-ft levels (1387 and 1478 m, respectively). In addition to Fermilab instruments, several high resolution Budker tiltmeters (1 μm resolution) will be installed in the mine workings in the near future, some

  19. Water resources data, Virginia, water year 2004 volume 2. Ground-water-level and ground-water-quality records

    USGS Publications Warehouse

    White, Roger K.; Powell, Eugene D.; Guyer, Joel R.; Owens, Joseph A.

    2005-01-01

    Water-resources data for the 2004 water year for Virginia consist of records of water levels and water quality of ground-water wells. This report (Volume 2. Ground-Water-Level and Ground-Water-Quality Records) contains water levels at 346 observation wells and water quality at 40 wells. Locations of these wells are shown on figures 4 through 9. The data in this report represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Virginia.

  20. The Organochlorine Pesticides Residue Levels in Karun River Water

    PubMed Central

    Behfar, Abdolazim; Nazari, Zahra; Rabiee, Mohammad Hassan; Raeesi, Gholamreza; Oveisi, Mohammad Reza; Sadeghi, Nafiseh; Jannat, Behrooz

    2013-01-01

    Background The organochlorine pesticides (OCPs) are among the most commonly used in water streams around the world. Most of these contaminants are highly hydrophobic and persist in sediments of rivers and lakes. Studies have suggested that OCPs may affect the normal function of the human and wildlife endocrine systems. Objectives The aim of this study is to determine the concentrations of selected organochlorine pesticides residues [OP'DDT, PP'DDT, alderin, dieldrin, heptachlor, (α,ß,γ,δ) HCH, (α, ß) endosulfan and metoxychlor] in samples from Karun River water at Khuzestan province in Iran , by GC-µ-ECD. Materials and Methods Water was extracted with n-hexane and then purified by passing through a glass column packed with Florisil and Na2SO4, which was then eluted with ether: hexane solution v/v. Results In general, all of 12 investigated organochlorine pesticides (OCPs) were detected. Regardless of the kind of OCPs, the highest OCP pollution level in Karun River were seen from August to November 2009 ranging 71.43 – 89.34 µg/L, and the lowest were seen from Dec 2010 to March 2011 at levels of 22.25 - 22.64 µg/L. The highest and lowest mean concentrations of 12 investigated pesticides were ß-Endosulfan and pp' DDT with 28.51and 0.01 µg/L respectively. Conclusions Comparison of total organochlorine pesticides residues concentration with WHO guidelines revealed that the Karun River had total OCPs residues above the probable effect level (0.2-20 µg/L, P < 0.05), which could pose a risk to aquatic life. PMID:24624185

  1. Water levels shape fishing participation in flood-control reservoirs

    USGS Publications Warehouse

    Miranda, Leandro E.; Meals, K. O.

    2013-01-01

    We examined the relationship between fishing effort (hours fished) and average March–May water level in 3 flood control reservoirs in Mississippi. Fishing effort increased as water level rose, peaked at intermediate water levels, and decreased at high water levels. We suggest that the observed arched-shaped relationship is driven by the shifting influence of fishability (adequacy of the fishing circumstances from an angler's perspective) and catch rate along a water level continuum. Fishability reduces fishing effort during low water, despite the potential for higher catch rates. Conversely, reduced catch rates and fishability at high water also curtail effort. Thus, both high and low water levels seem to discourage fishing effort, whereas anglers seem to favor intermediate water levels. Our results have implications for water level management in reservoirs with large water level fluctuations.

  2. Dysregulation of Cytokine Response in Canadian First Nations Communities: Is There an Association with Persistent Organic Pollutant Levels?

    PubMed Central

    Imbeault, Pascal; Findlay, C. Scott; Robidoux, Michael A.; Haman, François; Blais, Jules M.; Tremblay, Angelo; Springthorpe, Susan; Pal, Shinjini; Seabert, Tim; Krümmel, Eva M.; Maal-Bared, Rasha; Tetro, Jason A.; Pandey, Sunita; Sattar, Syed A.; Filion, Lionel G.

    2012-01-01

    In vitro and animal studies report that some persistent organic pollutants (POPs) trigger the secretion of proinflammatory cytokines. Whether POP exposure is associated with a dysregulation of cytokine response remains to be investigated in humans. We studied the strength of association between plasma POP levels and circulating cytokines as immune activation markers. Plasma levels of fourteen POPs and thirteen cytokines were measured in 39 Caucasians from a comparator sample in Québec City (Canada) and 72 First Nations individuals from two northern communities of Ontario (Canada). Caucasians showed significantly higher levels of organochlorine insecticides (β-HCH, p,p′-DDE and HCB) compared to First Nations. Conversely, First Nations showed higher levels of Mirex, Aroclor 1260, PCB 153, PCB 170, PCB 180 and PCB 187 compared to Caucasians. While there was no difference in cytokine levels of IL-4, IL-6, IL-10 and IL-22 between groups, First Nations had significantly greater average levels of IFNγ, IL-1β, IL-2, IL-5, IL-8, IL-12p70, IL-17A, TNFα and TNFβ levels compared to Caucasians. Among candidate predictor variables (age, body mass index, insulin resistance and POP levels), high levels of PCBs were the only predictor accounting for a small but significant effect of observed variance (∼7%) in cytokine levels. Overall, a weak but significant association is detected between persistent organochlorine pollutant exposure and elevated cytokine levels. This finding augments the already existing information that environmental pollution is related to inflammation, a common feature of several metabolic disorders that are known to be especially prevalent in Canada's remote First Nations communities. PMID:22768323

  3. Peripheral neurobiologic mechanisms of antiallodynic effect of warm water immersion therapy on persistent inflammatory pain.

    PubMed

    Martins, Daniel F; Brito, Rômulo N; Stramosk, Juliana; Batisti, Ana P; Madeira, Fernanda; Turnes, Bruna L; Mazzardo-Martins, Leidiane; Santos, Adair R S; Piovezan, Anna P

    2015-01-01

    Water immersion is widely used in physiotherapy and might relieve pain, probably by activating several distinct somatosensory modalities, including tactile, pressure, and thermal sensations. However, the endogenous mechanisms behind this effect remain poorly understood. This study examined whether warm water immersion therapy (WWIT) produces an antiallodynic effect in a model of localized inflammation and whether peripheral opioid, cannabinoid, and adenosine receptors are involved in this effect. Mice were injected with complete Freund's adjuvant (CFA; intraplantar; i.pl.). The withdrawal frequency to mechanical stimuli (von Frey test) was used to determine 1) the effect of WWIT against CFA-induced allodynia and 2) the effect of i.pl. preadministration of naloxone (a nonselective opioid receptor antagonist; 5 µg/paw), caffeine (a nonselective adenosine receptor antagonist; 150 nmol/paw), 1,3-dipropyl-8-cyclopentylxanthine (DPCPX; a selective adenosine A1 receptor antagonist; 10 nmol/paw), and AM630 (a selective cannabinoid receptor type 2 antagonist; 4 µg/paw) on the antiallodynic effect of WWIT against CFA-induced allodynia. Moreover, the influence of WWIT on paw inflammatory edema was measured with a digital micrometer. WWIT produced a significant time-dependent reduction of paw inflammatory allodynia but did not influence paw edema induced by CFA. Naloxone, caffeine, DPCPX, and AM630 injected in the right, but not in the left, hind paw significantly reversed the antiallodynic effect of WWIT. This is the first study to demonstrate the involvement of peripheral receptors in the antiallodynic effect of WWIT in a murine model of persistent inflammatory pain.

  4. Identifying Groundwater Droughts using standardized Water Levels

    NASA Astrophysics Data System (ADS)

    Haas, J. C.; Birk, S.

    2015-12-01

    Drought indices are frequently used to compare the occurrence and characteristics of droughts at different sites as well as to characterize different hydrometeorological aspects of drought. The existing indices have been mostly focused on precipitation, soil moisture, and surface waters though. To enable a comparison of groundwater drought with other hydrometeorological aspects of drought, the Standardized Groundwater level Index SGI was proposed by Bloomfield and Marchant (2013). So far, the SGI has been applied only to consolidated aquifers in the UK. The purpose of this work is to assess the applicability and performance of the SGI in unconsolidated, porous aquifers situated in valleys, which represent the main sources of drinking water in many regions. For this purpose, long-term time series of groundwater levels both in wet and dry regions of Austria are analyzed and compared with time series of precipitation, evapotranspiration and river stages. It is shown that large drought events, such as 2003 with only 79% of the long-term average precipitation, but also less severe events are reflected by negative SGI anomalies. To identify and classify time periods with a groundwater deficit, such benchmark years are used to propose a threshold value of the SGI defining the onset of a drought. Time periods where a clear drop in SGI does not correspond to a significant anomaly in precipitation are also visible in the data. More detailed investigations into small valley fill aquifers in the south-east of Austria reveal that the SGI may closely correlate with river stage fluctuations. Also, effects of the geographic setting (mountainous area vs. lowland) and the impacts of human activities (hydropower, drinking water extraction) are shown. Bloomfield, J. P., Marchant, B. P., Analysis of groundwater drought building on the standardised precipitation index approach, Hydrology and Earth System Sciences, 17, 4769-4787, 2013.

  5. Investigating the Persistence of a Snowpack Sublimation Stable Isotope Signal in Tree Xylem Water during the Growing Season

    NASA Astrophysics Data System (ADS)

    Schulze, E. S.; Bowling, D. R.

    2014-12-01

    Previous work identified a riparian meadow in the Rocky Mountains where streamside box elder (Acer negundo) trees did not use stream water, the most reliable and readily available source. A follow-up study showed that the water used by trees appears to be more evaporatively enriched than all available measured sources, including stream water, precipitation-derived soil water, and groundwater. While it is unlikely that there is a missing pool of water these trees are accessing, they may be tapping into a distinct subset of the bulk soil water available, possibly derived from much colder and older snowmelt. In this study, we investigated whether snowpack sublimation and subsequent melt water may impart an enriched isotopic signature that persists throughout the following growing season in less-mobile soil water pools. Profile samples of the snowpack, bulk melt water, and early season soil lysimeter water were collected throughout the winter and analyzed for hydrogen and oxygen stable isotopes. As snow began to melt in the spring, water samples for isotope analysis were taken from soil profiles, stream water, groundwater, and stems. Although sublimation likely occurred at the site, such processes did not impart an evaporative isotope enrichment on the snowpack throughout the season. Both snow pack and melt water remained closely tied to the local meteoric water line as they infiltrated soil. These findings suggest that snowpack sublimation processes preceding melt water infiltration are not the source of evaporative enrichment in tree water at our site.

  6. CMS software architecture. Software framework, services and persistency in high level trigger, reconstruction and analysis

    NASA Astrophysics Data System (ADS)

    Innocente, V.; Silvestris, L.; Stickland, D.; CMS Software Group

    2001-10-01

    This paper describes the design of a resilient and flexible software architecture that has been developed to satisfy the data processing requirements of a large HEP experiment, CMS, currently being constructed at the LHC machine at CERN. We describe various components of a software framework that allows integration of physics modules and which can be easily adapted for use in different processing environments both real-time (online trigger) and offline (event reconstruction and analysis). Features such as the mechanisms for scheduling algorithms, configuring the application and managing the dependences among modules are described in detail. In particular, a major effort has been placed on providing a service for managing persistent data and the experience using a commercial ODBMS (Objectivity/DB) is therefore described in detail.

  7. Persistently Elevated C-Reactive Protein Level in the First Year of Antiretroviral Therapy, Despite Virologic Suppression, Is Associated With HIV Disease Progression in Resource-Constrained Settings.

    PubMed

    Shivakoti, Rupak; Yang, Wei-Teng; Berendes, Sima; Mwelase, Noluthando; Kanyama, Cecilia; Pillay, Sandy; Samaneka, Wadzanai; Santos, Breno; Poongulali, Selvamuthu; Tripathy, Srikanth; Riviere, Cynthia; Lama, Javier R; Cardoso, Sandra W; Sugandhavesa, Patcharaphan; Balagopal, Ashwin; Gupte, Nikhil; Semba, Richard D; Campbell, Thomas B; Bollinger, Robert C; Gupta, Amita

    2016-04-01

    A case-cohort analysis of human immunodeficiency virus (HIV)-infected individuals receiving antiretroviral therapy (ART) was performed within a multicountry randomized trial (PEARLS) to assess the prevalence of persistently elevated C-reactive protein (CRP) levels, based on serial measurements of CRP levels, and their association with HIV clinical failure. A persistently elevated CRP level in plasma (defined as ≥ 5 mg/L at both baseline and 24 weeks after ART initiation) was observed in 50 of 205 individuals (24%). A persistently elevated CRP level but not an elevated CRP level only at a single time point was independently associated with increased clinical failure, compared with a persistently low CRP level, despite achievement of virologic suppression. Serial monitoring of CRP levels could identify individuals who are at highest risk of HIV progression and may benefit from future adjunct antiinflammatory therapies. PMID:26621909

  8. Detection, integration and persistence of aeromonads in water distribution pipe biofilms.

    PubMed

    Bomo, A-M; Storey, M V; Ashbolt, N J

    2004-06-01

    The occurrence of Aeromonas spp. within biofilms formed on stainless steel (SS), unplasticized polyvinyl chloride (uPVC) and glass (GL) substrata was investigated in modified Robbins Devices (MRD) in potable (MRD-p) and recycled (MRD-r) water systems, a Biofilm Reactor (BR) and a laboratory-scale pipe loop (PL) receiving simulated recycled wastewater. No aeromonads were isolated from the MRD-p whereas 3-10% of SS and uPVC coupons (mean 3.85 CFU cm(-2) and 12.8 CFU cm(-2), respectively) were aeromonad-positive in the MRD-r. Aeromonads were isolated from six SS coupons (67%) (mean 63.4 CFU cm(-2)) and nine uPVC coupons (100%) (mean 6.50x 10(2) CFU cm(-2)) in the BR fed with recycled water and from all coupons (100%) in the simulated recycled water system (PL). Mean numbers of aeromonads on GL and SS coupons were 5.83 x 10(2) CFU cm(-2) and 8.73 x 10(2) CFU cm(-2), respectively. No isolate was of known human health significance (i.e. Aeromonas caviae, A. hydrophila or A. veronii), though they were confirmed as Aeromonas spp. by PCR and fluorescence in situ hybridization (FISH). Challenging the PL biofilms with a slug dose of A. hydrophila (ATCC 14715) showed that biofilm in the PL accumulated in the order of 10(3)-10(4) A. hydrophila cm(-2), the number of which decreased over time, though could not be explained in terms of conventional 1st order decay kinetics. A sub-population of FISH-positive A. hydrophila became established within the biofilm, thereby demonstrating their ability to incorporate and persist in biofilms formed within distribution pipe systems. A similar observation was not made for culturable aeromonads, though the exact human health significance of this remains unknown. These findings, however, further question the adequacy of culture-based techniques and their often anomalous discrepancy with direct techniques for the enumeration of bacterial pathogens in environmental samples. PMID:15387132

  9. Persistence of HCV in Acutely-Infected Patients Depletes C24-Ceramide and Upregulates Sphingosine and Sphinganine Serum Levels

    PubMed Central

    Grammatikos, Georgios; Dietz, Julia; Ferreiros, Nerea; Koch, Alexander; Dultz, Georg; Bon, Dimitra; Karakasiliotis, Ioannis; Lutz, Thomas; Knecht, Gaby; Gute, Peter; Herrmann, Eva; Zeuzem, Stefan; Mavromara, Penelope; Sarrazin, Christoph; Pfeilschifter, Josef

    2016-01-01

    Hepatitis C virus (HCV) substantially affects lipid metabolism, and remodeling of sphingolipids appears to be essential for HCV persistence in vitro. The aim of the current study is the evaluation of serum sphingolipid variations during acute HCV infection. We enrolled prospectively 60 consecutive patients with acute HCV infection, most of them already infected with human immunodeficiency virus (HIV), and serum was collected at the time of diagnosis and longitudinally over a six-month period until initiation of antiviral therapy or confirmed spontaneous clearance. Quantification of serum sphingolipids was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Spontaneous clearance was observed in 11 out of 60 patients (18.3%), a sustained viral response (SVR) in 43 out of 45 patients (95.5%) receiving an antiviral treatment after follow-up, whereas persistence of HCV occurred in six out of 60 patients (10%). C24-ceramide (C24-Cer)-levels increased at follow-up in patients with spontaneous HCV eradication (p < 0.01), as compared to baseline. Sphingosine and sphinganine values were significantly upregulated in patients unable to clear HCV over time compared to patients with spontaneous clearance of HCV infection on follow-up (p = 0.013 and 0.006, respectively). In summary, the persistence of HCV after acute infection induces a downregulation of C24Cer and a simultaneous elevation of serum sphingosine and sphinganine concentrations. PMID:27304952

  10. Modeling the influence of temperature, water activity and water mobility on the persistence of Salmonella in low-moisture foods.

    PubMed

    Farakos, S M Santillana; Frank, J F; Schaffner, D W

    2013-09-01

    Salmonella can survive in low-moisture foods for long periods of time. Reduced microbial inactivation during heating is believed to be due to the interaction of cells and water, and is thought to be related to water activity (a(w)). Little is known about the role of water mobility in influencing the survival of Salmonella in low-moisture foods. The aim of this study was to determine how the physical state of water in low-moisture foods influences the survival of Salmonella and to use this information to develop mathematical models that predict the behavior of Salmonella in these foods. Whey protein powder of differing water mobilities was produced by pH adjustment and heat denaturation, and then equilibrated to aw levels between 0.19±0.03 and 0.54±0.02. Water mobility was determined by wide-line proton-NMR. Powders were inoculated with a four-strain cocktail of Salmonella, vacuum-sealed and stored at 21, 36, 50, 60, 70 and 80°C. Survival data was fitted to the log-linear, the Geeraerd-tail, the Weibull, the biphasic-linear and the Baranyi models. The model with the best ability to describe the data over all temperatures, water activities and water mobilities (f(test)water mobility on the survival of Salmonella was evaluated using multiple linear regression. Secondary models were developed and then validated in dry non-fat dairy and grain, and low-fat peanut and cocoa products within the range of the modeled data. Water activity significantly influenced the survival of Salmonella at all temperatures, survival increasing with decreasing a(w). Water mobility did not significantly influence survival independent of a(w). Secondary models were useful in predicting the survival of Salmonella in various low-moisture foods providing a correlation of R=0.94 and an acceptable prediction performance of 81

  11. Modeling the influence of temperature, water activity and water mobility on the persistence of Salmonella in low-moisture foods.

    PubMed

    Farakos, S M Santillana; Frank, J F; Schaffner, D W

    2013-09-01

    Salmonella can survive in low-moisture foods for long periods of time. Reduced microbial inactivation during heating is believed to be due to the interaction of cells and water, and is thought to be related to water activity (a(w)). Little is known about the role of water mobility in influencing the survival of Salmonella in low-moisture foods. The aim of this study was to determine how the physical state of water in low-moisture foods influences the survival of Salmonella and to use this information to develop mathematical models that predict the behavior of Salmonella in these foods. Whey protein powder of differing water mobilities was produced by pH adjustment and heat denaturation, and then equilibrated to aw levels between 0.19±0.03 and 0.54±0.02. Water mobility was determined by wide-line proton-NMR. Powders were inoculated with a four-strain cocktail of Salmonella, vacuum-sealed and stored at 21, 36, 50, 60, 70 and 80°C. Survival data was fitted to the log-linear, the Geeraerd-tail, the Weibull, the biphasic-linear and the Baranyi models. The model with the best ability to describe the data over all temperatures, water activities and water mobilities (f(test)water mobility on the survival of Salmonella was evaluated using multiple linear regression. Secondary models were developed and then validated in dry non-fat dairy and grain, and low-fat peanut and cocoa products within the range of the modeled data. Water activity significantly influenced the survival of Salmonella at all temperatures, survival increasing with decreasing a(w). Water mobility did not significantly influence survival independent of a(w). Secondary models were useful in predicting the survival of Salmonella in various low-moisture foods providing a correlation of R=0.94 and an acceptable prediction performance of 81

  12. Population-level thermal performance of a cold-water ectotherm is linked to ontogeny and local environmental heterogeneity

    USGS Publications Warehouse

    Hossack, Blake R.; Corn, P. Stephen; , Winsor H. Lowe; , Molly A. H. Webb; , Mariah J. Talbott; , Kevin M. Kappenman

    2013-01-01

    5. Our experiments with a cold-water species show that population-level performance varies across small geographic scales and is linked to local environmental heterogeneity. This variation could influence the rate and mode of species-level responses to climate change, both by facilitating local persistence in the face of change

  13. Programmatic Use of Molecular Xenomonitoring at the Level of Evaluation Units to Assess Persistence of Lymphatic Filariasis in Sri Lanka

    PubMed Central

    Rao, Ramakrishna U.; Samarasekera, Sandhya D.; Nagodavithana, Kumara C.; Punchihewa, Manjula W.; Dassanayaka, Tharanga D. M.; P. K. D, Gamini; Ford, Ethan; Ranasinghe, Udaya S. B.; Henderson, Ralph H.; Weil, Gary J.

    2016-01-01

    Background Sri Lanka’s Anti Filariasis Campaign distributed 5 rounds of mass drug administration (MDA with DEC plus albendazole) to all endemic regions in the country from 2002–2006. Post-MDA surveillance results have generally been encouraging. However, recent studies have documented low level persistence of Wuchereria bancrofti in Galle district based on comprehensive surveys that include molecular xenomonitoring (MX, detection of filarial DNA in mosquitoes) results. The purposes of this study were to demonstrate the use of MX in large evaluation units (EUs) and to field test different mosquito sampling schemes. Methodology/Principal Findings Galle district (population 1.1 million) was divided into two EUs. These included a coastal EU with known persistent LF and an inland EU with little persistent LF. Mosquitoes were systematically sampled from ~300 trap locations in 30 randomly selected clusters (health administrative units) per EU. Approximately 28,000 Culex quinquefasciatus were collected with gravid traps and tested for filarial DNA by qPCR. 92/625 pools (14.7%) from the coastal EU and 8/583 pools (1.4%) from the inland EU were positive for filarial DNA. Maximum likelihood estimates (MLE) for filarial DNA rates were essentially the same when the same number of mosquito pools were collected and tested from 75, 150, or 300 trap sites (range 0.61–0.78% for the coastal EU and 0.04–0.07% for the inland EU). The ability to use a smaller number of trap sites reduces the cost and time required for mosquito sampling. Conclusions/Significance These results suggest there is widespread persistence of W. bancrofti infection in the coastal Galle EU 8 years after the last round of MDA in 2006, and this is consistent with other data from the district. This study has shown that MX can be used by national programs to assess and map the persistence of W. bancrofti at the level of large EUs in areas with Culex transmission. PMID:27196431

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

    NASA Astrophysics Data System (ADS)

    Shuai, Danmeng

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

  15. Salmon-Eating Grizzly Bears Exposed to Elevated Levels of Marine Derived Persistent Organic Pollutants

    NASA Astrophysics Data System (ADS)

    Christensen, J. R.; Ross, P. S.; Whiticar, M. J.

    2004-12-01

    The coastal grizzly bears of British Columbia (BC, Canada) rely heavily on salmon returning from the Pacific Ocean, whereas interior bears do not have access to or readily utilize this marine-derived food source. Since salmon have been shown to accumulate persistent organic pollutants (POPs) from the North Pacific Ocean, we hypothesized that salmon consumption by grizzly bears would be reflected by an increase in the POP burden. To test this hypothesis we collected hair and fat tissue from grizzlies at various locations around BC to compare salmon-eating (coastal) grizzlies to non-salmon-eating (interior) grizzlies. We characterized the feeding habits for each bear sampled by measuring the stable carbon and nitrogen isotope signature of their hair. The positive relationship between 13C/12C and 15N/14N isotopic ratios suggests that the majority of the meat portion of the diet of coastal grizzlies is coming from salmon, rather than from terrestrial or freshwater sources. By contrast, stable isotope ratios revealed that interior bears have an almost exclusive vegetarian diet with no marine influence. As hypothesized, the coastal grizzly bears have significantly greater OC pesticide and lower-brominated PBDE congener body burden than the interior grizzlies. We also found a positive relationship between C and N isotope ratios and these same POP contaminants in bear tissue. Overall, these results demonstrate that Pacific salmon represents a significant vector delivering both OC pesticides and PBDEs to BC coastal grizzly bears.

  16. Impact of the shedding level on transmission of persistent infections in Mycobacterium avium subspecies paratuberculosis (MAP).

    PubMed

    Slater, Noa; Mitchell, Rebecca Mans; Whitlock, Robert H; Fyock, Terry; Pradhan, Abani Kumar; Knupfer, Elena; Schukken, Ynte Hein; Louzoun, Yoram

    2016-01-01

    Super-shedders are infectious individuals that contribute a disproportionate amount of infectious pathogen load to the environment. A super-shedder host may produce up to 10,000 times more pathogens than other infectious hosts. Super-shedders have been reported for multiple human and animal diseases. If their contribution to infection dynamics was linear to the pathogen load, they would dominate infection dynamics. We here focus on quantifying the effect of super-shedders on the spread of infection in natural environments to test if such an effect actually occurs in Mycobacterium avium subspecies paratuberculosis (MAP). We study a case where the infection dynamics and the bacterial load shed by each host at every point in time are known. Using a maximum likelihood approach, we estimate the parameters of a model with multiple transmission routes, including direct contact, indirect contact and a background infection risk. We use longitudinal data from persistent infections (MAP), where infectious individuals have a wide distribution of infectious loads, ranging upward of three orders of magnitude. We show based on these parameters that the effect of super-shedders for MAP is limited and that the effect of the individual bacterial load is limited and the relationship between bacterial load and the infectiousness is highly concave. A 1000-fold increase in the bacterial contribution is equivalent to up to a 2-3 fold increase in infectiousness.

  17. Intraspecific Variation among Social Insect Colonies: Persistent Regional and Colony-Level Differences in Fire Ant Foraging Behavior

    PubMed Central

    Bockoven, Alison A.; Wilder, Shawn M.; Eubanks, Micky D.

    2015-01-01

    Individuals vary within a species in many ecologically important ways, but the causes and consequences of such variation are often poorly understood. Foraging behavior is among the most profitable and risky activities in which organisms engage and is expected to be under strong selection. Among social insects there is evidence that within-colony variation in traits such as foraging behavior can increase colony fitness, but variation between colonies and the potential consequences of such variation are poorly documented. In this study, we tested natural populations of the red imported fire ant, Solenopsis invicta, for the existence of colony and regional variation in foraging behavior and tested the persistence of this variation over time and across foraging habitats. We also reared single-lineage colonies in standardized environments to explore the contribution of colony lineage. Fire ants from natural populations exhibited significant and persistent colony and regional-level variation in foraging behaviors such as extra-nest activity, exploration, and discovery of and recruitment to resources. Moreover, colony-level variation in extra-nest activity was significantly correlated with colony growth, suggesting that this variation has fitness consequences. Lineage of the colony had a significant effect on extra-nest activity and exploratory activity and explained approximately half of the variation observed in foraging behaviors, suggesting a heritable component to colony-level variation in behavior. PMID:26197456

  18. Intraspecific Variation among Social Insect Colonies: Persistent Regional and Colony-Level Differences in Fire Ant Foraging Behavior.

    PubMed

    Bockoven, Alison A; Wilder, Shawn M; Eubanks, Micky D

    2015-01-01

    Individuals vary within a species in many ecologically important ways, but the causes and consequences of such variation are often poorly understood. Foraging behavior is among the most profitable and risky activities in which organisms engage and is expected to be under strong selection. Among social insects there is evidence that within-colony variation in traits such as foraging behavior can increase colony fitness, but variation between colonies and the potential consequences of such variation are poorly documented. In this study, we tested natural populations of the red imported fire ant, Solenopsis invicta, for the existence of colony and regional variation in foraging behavior and tested the persistence of this variation over time and across foraging habitats. We also reared single-lineage colonies in standardized environments to explore the contribution of colony lineage. Fire ants from natural populations exhibited significant and persistent colony and regional-level variation in foraging behaviors such as extra-nest activity, exploration, and discovery of and recruitment to resources. Moreover, colony-level variation in extra-nest activity was significantly correlated with colony growth, suggesting that this variation has fitness consequences. Lineage of the colony had a significant effect on extra-nest activity and exploratory activity and explained approximately half of the variation observed in foraging behaviors, suggesting a heritable component to colony-level variation in behavior. PMID:26197456

  19. Ultra-sensitive in-situ detection of near-infrared persistent luminescent tracer nanoagents in crude oil-water mixtures

    NASA Astrophysics Data System (ADS)

    Chuang, Yen-Jun; Liu, Feng; Wang, Wei; Kanj, Mazen Y.; Poitzsch, Martin E.; Pan, Zhengwei

    2016-06-01

    Current fluorescent nanoparticles-based tracer sensing techniques for oilfield applications suffer from insufficient sensitivity, with the tracer detection limit typically at the several hundred ppm level in untreated oil/water mixtures, which is mainly caused by the interference of the background fluorescence from the organic residues in crude oil under constant external excitation. Here we report the use of a persistent luminescence phenomenon, which enables an external excitation-free and thus background fluorescence-free measurement condition, for ultrahigh-sensitivity crude oil sensing. By using LiGa5O8:Cr3+ near-infrared persistent luminescent nanoparticles as a tracer nanoagent, we achieved a tracer detection limit at the single-digit ppb level (down to 1 ppb concentration of nanoparticles) in high oil fraction (up to 65 wt.%) oil/water mixtures via a convenient, CCD camera-based imaging technique without any pretreatment or phase separation of the fluid samples. This detection limit is about four to five orders of magnitude lower than that obtained using conventional spectral methods. This study introduces a new type of tracer nanoagents and a new detection method for water tracer sensing in oil reservoir characterization and management.

  20. Ultra-sensitive in-situ detection of near-infrared persistent luminescent tracer nanoagents in crude oil-water mixtures.

    PubMed

    Chuang, Yen-Jun; Liu, Feng; Wang, Wei; Kanj, Mazen Y; Poitzsch, Martin E; Pan, Zhengwei

    2016-06-15

    Current fluorescent nanoparticles-based tracer sensing techniques for oilfield applications suffer from insufficient sensitivity, with the tracer detection limit typically at the several hundred ppm level in untreated oil/water mixtures, which is mainly caused by the interference of the background fluorescence from the organic residues in crude oil under constant external excitation. Here we report the use of a persistent luminescence phenomenon, which enables an external excitation-free and thus background fluorescence-free measurement condition, for ultrahigh-sensitivity crude oil sensing. By using LiGa5O8:Cr(3+) near-infrared persistent luminescent nanoparticles as a tracer nanoagent, we achieved a tracer detection limit at the single-digit ppb level (down to 1 ppb concentration of nanoparticles) in high oil fraction (up to 65 wt.%) oil/water mixtures via a convenient, CCD camera-based imaging technique without any pretreatment or phase separation of the fluid samples. This detection limit is about four to five orders of magnitude lower than that obtained using conventional spectral methods. This study introduces a new type of tracer nanoagents and a new detection method for water tracer sensing in oil reservoir characterization and management.

  1. Ultra-sensitive in-situ detection of near-infrared persistent luminescent tracer nanoagents in crude oil-water mixtures

    PubMed Central

    Chuang, Yen-Jun; Liu, Feng; Wang, Wei; Kanj, Mazen Y.; Poitzsch, Martin E.; Pan, Zhengwei

    2016-01-01

    Current fluorescent nanoparticles-based tracer sensing techniques for oilfield applications suffer from insufficient sensitivity, with the tracer detection limit typically at the several hundred ppm level in untreated oil/water mixtures, which is mainly caused by the interference of the background fluorescence from the organic residues in crude oil under constant external excitation. Here we report the use of a persistent luminescence phenomenon, which enables an external excitation-free and thus background fluorescence-free measurement condition, for ultrahigh-sensitivity crude oil sensing. By using LiGa5O8:Cr3+ near-infrared persistent luminescent nanoparticles as a tracer nanoagent, we achieved a tracer detection limit at the single-digit ppb level (down to 1 ppb concentration of nanoparticles) in high oil fraction (up to 65 wt.%) oil/water mixtures via a convenient, CCD camera-based imaging technique without any pretreatment or phase separation of the fluid samples. This detection limit is about four to five orders of magnitude lower than that obtained using conventional spectral methods. This study introduces a new type of tracer nanoagents and a new detection method for water tracer sensing in oil reservoir characterization and management. PMID:27302076

  2. Do pharmaceuticals, pathogens, and other organic waste water compounds persist when waste water is used for recharge?

    USGS Publications Warehouse

    Cordy, Gail E.; Duran, Norma L.; Bouwer, Herman; Rice, Robert C.; Furlong, Edward T.; Zaugg, Steven D.; Meyer, Michael T.; Barber, Larry B.; Kolpin, Dana W.

    2004-01-01

    A proof-of-concept experiment was devised to determine if pharmaceuticals and other organic waste water compounds (OWCs), as well as pathogens, found in treated effluent could be transported through a 2.4 m soil column and, thus, potentially reach ground water under recharge conditions similar to those in arid or semiarid climates. Treated effluent was applied at the top of the 2.4 m long, 32.5 cm diameter soil column over 23 days, Samples of the column inflow were collected from the effluent storage tank at the beginning (Tbegin) and end (Tend) of the experiment, and a sample of the soil column drainage at the base of the column (Bend) was collected at the end of the experiment. Samples were analyzed for 131 OWCs including veterinary and human antibiotics, other prescription and nonprescription drugs, widely used household and industrial chemicals, and steroids and reproductive hormones, as well as the pathogens Salmonella and Legionella. Analytical results for the two effluent samples taken at the beginning (Tbegin) and end (Tend) of the experiment indicate that the number of OWCs detected in the column inflow decreased by 25% (eight compounds) and the total concentration of OWCs decreased by 46% while the effluent was in the storage tank during the 23-day experiment. After percolating through the soil column, an additional 18 compounds detected in Tend (67% of OWCs) were no longer detected in the effluent (Bend) and the total concentration of OWCs decreased by more than 70%. These compounds may have been subject to transformation (biotic and abiotic), adsorption, and (or) volatilization in the storage tank and during travel through the soil column. Eight compounds—carbamazapine; sulfamethoxazole; benzophenone; 5-methyl-1H-benzotriazole; N,N-diethyltoluamide; tributylphosphate; tri(2-chloroethyl) phosphate; and cholesterol—were detected in all three samples indicating they have the potential to reach ground water under recharge conditions similar to those in

  3. Increasing sample size in prospective birth cohorts: back-extrapolating prenatal levels of persistent organic pollutants in newly enrolled children.

    PubMed

    Verner, Marc-André; Gaspar, Fraser W; Chevrier, Jonathan; Gunier, Robert B; Sjödin, Andreas; Bradman, Asa; Eskenazi, Brenda

    2015-03-17

    Study sample size in prospective birth cohorts of prenatal exposure to persistent organic pollutants (POPs) is limited by costs and logistics of follow-up. Increasing sample size at the time of health assessment would be beneficial if predictive tools could reliably back-extrapolate prenatal levels in newly enrolled children. We evaluated the performance of three approaches to back-extrapolate prenatal levels of p,p'-dichlorodiphenyltrichloroethane (DDT), p,p'-dichlorodiphenyldichloroethylene (DDE) and four polybrominated diphenyl ether (PBDE) congeners from maternal and/or child levels 9 years after delivery: a pharmacokinetic model and predictive models using deletion/substitution/addition or Super Learner algorithms. Model performance was assessed using the root mean squared error (RMSE), R2, and slope and intercept of the back-extrapolated versus measured levels. Super Learner outperformed the other approaches with RMSEs of 0.10 to 0.31, R2s of 0.58 to 0.97, slopes of 0.42 to 0.93 and intercepts of 0.08 to 0.60. Typically, models performed better for p,p'-DDT/E than PBDE congeners. The pharmacokinetic model performed well when back-extrapolating prenatal levels from maternal levels for compounds with longer half-lives like p,p'-DDE and BDE-153. Results demonstrate the ability to reliably back-extrapolate prenatal POP levels from levels 9 years after delivery, with Super Learner performing best based on our fit criteria. PMID:25698216

  4. Hydrological drivers of record-setting water level rise on Earth's largest lake system

    NASA Astrophysics Data System (ADS)

    Gronewold, A. D.; Bruxer, J.; Durnford, D.; Smith, J. P.; Clites, A. H.; Seglenieks, F.; Qian, S. S.; Hunter, T. S.; Fortin, V.

    2016-05-01

    Between January 2013 and December 2014, water levels on Lake Superior and Lake Michigan-Huron, the two largest lakes on Earth by surface area, rose at the highest rate ever recorded for a 2 year period beginning in January and ending in December of the following year. This historic event coincided with below-average air temperatures and extensive winter ice cover across the Great Lakes. It also brought an end to a 15 year period of persistently below-average water levels on Lakes Superior and Michigan-Huron that included several months of record-low water levels. To differentiate hydrological drivers behind the recent water level rise, we developed a Bayesian Markov chain Monte Carlo (MCMC) routine for inferring historical estimates of the major components of each lake's water budget. Our results indicate that, in 2013, the water level rise on Lake Superior was driven by increased spring runoff and over-lake precipitation. In 2014, reduced over-lake evaporation played a more significant role in Lake Superior's water level rise. The water level rise on Lake Michigan-Huron in 2013 was also due to above-average spring runoff and persistent over-lake precipitation, while in 2014, it was due to a rare combination of below-average evaporation, above-average runoff and precipitation, and very high inflow rates from Lake Superior through the St. Marys River. We expect, in future research, to apply our new framework across the other Laurentian Great Lakes, and to Earth's other large freshwater basins as well.

  5. A Simple, Inexpensive Water-Leveling Device for Ultramicrotomy.

    ERIC Educational Resources Information Center

    Brooks, Austin E.

    1978-01-01

    Describes a device for maintaining the proper water level in knife boats during ultramicrotomy. Water levels in troughs are adjusted rapidly and precisely during the cutting process. Illustrations are included. (Author/MA)

  6. Ground-water levels in Anchorage, Alaska, 1985

    USGS Publications Warehouse

    Glass, R.L.

    1987-01-01

    Water-level data collected during 1985 for 146 Anchorage wells deeper than 40 feet are presented. Hydrographs of water levels in 20 wells for the period 1970 through 1985 are also given. The report describes groundwater conditions and seasonal fluctuations in water levels, and includes pumpage figures and well-construction data. (USGS)

  7. County Level Assessment of Impaired Waters and Gastrointestinal Infections

    EPA Science Inventory

    Water quality data are measured at a watershed level and health data are organized at different levels of aggregation therefore, assessing the population-level impact of water quality on health can be difficult. To address this discrepancy and enable the consideration of water ...

  8. Effect of disinfectant, water age, and pipe material on occurrence and persistence of Legionella, mycobacteria, Pseudomonas aeruginosa, and two amoebas.

    PubMed

    Wang, Hong; Masters, Sheldon; Hong, Yanjuan; Stallings, Jonathan; Falkinham, Joseph O; Edwards, Marc A; Pruden, Amy

    2012-11-01

    Opportunistic pathogens represent a unique challenge because they establish and grow within drinking water systems, yet the factors stimulating their proliferation are largely unknown. The purpose of this study was to examine the influence of pipe materials, disinfectant type, and water age on occurrence and persistence of three opportunistic pathogens (Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa), broader genera (Legionella and mycobacteria), and two amoeba hosts (Acanthamoeba spp. and Hartmanella vermiformis). Triplicate simulated distribution systems (SDSs) compared iron, cement, and PVC pipe materials fed either chlorinated or chloraminated tap water and were sampled at water ages ranging from 1 day to 5.7 days. Quantitative polymerase chain reaction quantified gene copies of target microorganisms in both biofilm and bulk water. Legionella, mycobacteria, P. aeruginosa, and both amoebas naturally colonized the six SDSs, but L. pneumophila and M. avium were not detected. Disinfectant type and dose was observed to have the strongest influence on the microbiota. Disinfectant decay was noted with water age, particularly in chloraminated SDSs (due to nitrification), generally resulting in increased microbial detection frequencies and densities with water age. The influence of pipe material became apparent at water ages corresponding to low disinfectant residual. Each target microbe appeared to display a distinct response to disinfectant type, pipe materials, water age, and their interactions. Differences between the first and the second samplings (e.g., appearance of Legionella, reduction in P. aeruginosa and Acanthamoeba) suggest a temporally dynamic drinking water microbial community.

  9. Effect of disinfectant, water age, and pipe material on occurrence and persistence of Legionella, mycobacteria, Pseudomonas aeruginosa, and two amoebas.

    PubMed

    Wang, Hong; Masters, Sheldon; Hong, Yanjuan; Stallings, Jonathan; Falkinham, Joseph O; Edwards, Marc A; Pruden, Amy

    2012-11-01

    Opportunistic pathogens represent a unique challenge because they establish and grow within drinking water systems, yet the factors stimulating their proliferation are largely unknown. The purpose of this study was to examine the influence of pipe materials, disinfectant type, and water age on occurrence and persistence of three opportunistic pathogens (Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa), broader genera (Legionella and mycobacteria), and two amoeba hosts (Acanthamoeba spp. and Hartmanella vermiformis). Triplicate simulated distribution systems (SDSs) compared iron, cement, and PVC pipe materials fed either chlorinated or chloraminated tap water and were sampled at water ages ranging from 1 day to 5.7 days. Quantitative polymerase chain reaction quantified gene copies of target microorganisms in both biofilm and bulk water. Legionella, mycobacteria, P. aeruginosa, and both amoebas naturally colonized the six SDSs, but L. pneumophila and M. avium were not detected. Disinfectant type and dose was observed to have the strongest influence on the microbiota. Disinfectant decay was noted with water age, particularly in chloraminated SDSs (due to nitrification), generally resulting in increased microbial detection frequencies and densities with water age. The influence of pipe material became apparent at water ages corresponding to low disinfectant residual. Each target microbe appeared to display a distinct response to disinfectant type, pipe materials, water age, and their interactions. Differences between the first and the second samplings (e.g., appearance of Legionella, reduction in P. aeruginosa and Acanthamoeba) suggest a temporally dynamic drinking water microbial community. PMID:23046164

  10. Demographic, behavioral, dietary, and socioeconomic characteristics related to persistent organic pollutants and mercury levels in pregnant women in Japan.

    PubMed

    Miyashita, Chihiro; Sasaki, Seiko; Saijo, Yasuaki; Okada, Emiko; Kobayashi, Sumitaka; Baba, Toshiaki; Kajiwara, Jumboku; Todaka, Takashi; Iwasaki, Yusuke; Nakazawa, Hiroyuki; Hachiya, Noriyuki; Yasutake, Akira; Murata, Katsuyuki; Kishi, Reiko

    2015-08-01

    Persistent organic pollutants and mercury are known environmental chemicals that have been found to be ubiquitous in not only the environment but also in humans, including women of reproductive age. The purpose of this study was to evaluate the association between personal lifestyle characteristics and environmental chemical levels during the perinatal period in the general Japanese population. This study targeted 322 pregnant women enrolled in the Hokkaido Study on Environment and Children's Health. Each participant completed a self-administered questionnaire and a food-frequency questionnaire to obtain relevant information on parental demographic, behavioral, dietary, and socioeconomic characteristics. In total, 58 non-dioxin-like polychlorinated biphenyls, 17 dibenzo-p-dioxins and -dibenzofuran, and 12 dioxin-like polychlorinated biphenyls congeners, perfluorooctane sulfonate, perfluorooctanoic acid, and mercury were measured in maternal samples taken during the perinatal period. Linear regression models were constructed against potential related factors for each chemical concentration. Most concentrations of environmental chemicals were correlated with the presence of other environmental chemicals, especially in the case of non-dioxin-like polychlorinated biphenyls and, polychlorinated dibenzo-p-dioxins and -dibezofurans and dioxin-like polychlorinated biphenyls which had similar exposure sources and persistence in the body. Maternal smoking and alcohol habits, fish and beef intake and household income were significantly associated with concentrations of environmental chemicals. These results suggest that different lifestyle patterns relate to varying exposure to environmental chemicals.

  11. Demographic, behavioral, dietary, and socioeconomic characteristics related to persistent organic pollutants and mercury levels in pregnant women in Japan.

    PubMed

    Miyashita, Chihiro; Sasaki, Seiko; Saijo, Yasuaki; Okada, Emiko; Kobayashi, Sumitaka; Baba, Toshiaki; Kajiwara, Jumboku; Todaka, Takashi; Iwasaki, Yusuke; Nakazawa, Hiroyuki; Hachiya, Noriyuki; Yasutake, Akira; Murata, Katsuyuki; Kishi, Reiko

    2015-08-01

    Persistent organic pollutants and mercury are known environmental chemicals that have been found to be ubiquitous in not only the environment but also in humans, including women of reproductive age. The purpose of this study was to evaluate the association between personal lifestyle characteristics and environmental chemical levels during the perinatal period in the general Japanese population. This study targeted 322 pregnant women enrolled in the Hokkaido Study on Environment and Children's Health. Each participant completed a self-administered questionnaire and a food-frequency questionnaire to obtain relevant information on parental demographic, behavioral, dietary, and socioeconomic characteristics. In total, 58 non-dioxin-like polychlorinated biphenyls, 17 dibenzo-p-dioxins and -dibenzofuran, and 12 dioxin-like polychlorinated biphenyls congeners, perfluorooctane sulfonate, perfluorooctanoic acid, and mercury were measured in maternal samples taken during the perinatal period. Linear regression models were constructed against potential related factors for each chemical concentration. Most concentrations of environmental chemicals were correlated with the presence of other environmental chemicals, especially in the case of non-dioxin-like polychlorinated biphenyls and, polychlorinated dibenzo-p-dioxins and -dibezofurans and dioxin-like polychlorinated biphenyls which had similar exposure sources and persistence in the body. Maternal smoking and alcohol habits, fish and beef intake and household income were significantly associated with concentrations of environmental chemicals. These results suggest that different lifestyle patterns relate to varying exposure to environmental chemicals. PMID:25829055

  12. Water vapour and heat combine to elicit biting and biting persistence in tsetse

    PubMed Central

    2013-01-01

    Background Tsetse flies are obligatory blood feeders, accessing capillaries by piercing the skin of their hosts with the haustellum to suck blood. However, this behaviour presents a considerable risk as landing flies are exposed to predators as well as the host’s own defense reactions such as tail flicking. Achieving a successful blood meal within the shortest time span is therefore at a premium in tsetse, so feeding until replete normally lasts less than a minute. Biting in blood sucking insects is a multi-sensory response involving a range of physical and chemical stimuli. Here we investigated the role of heat and humidity emitted from host skin on the biting responses of Glossina pallidipes, which to our knowledge has not been fully studied in tsetse before. Methods The onset and duration of the biting response of G. pallidipes was recorded by filming movements of its haustellum in response to rapid increases in temperature and/or relative humidity (RH) following exposure of the fly to two airflows. The electrophysiological responses of hygroreceptor cells in wall-pore sensilla on the palps of G. pallidipes to drops in RH were recorded using tungsten electrodes and the ultra-structure of these sensory cells was studied by scanning and transmission electron microscopy. Results Both latency and proportion of tsetse biting are closely correlated to RH when accompanied by an increase of 13.1°C above ambient temperature but not for an increase of just 0.2°C. Biting persistence, as measured by the number of bites and the time spent biting, also increases with increasing RH accompanied by a 13.1°C increase in air temperature. Neurones in wall-pore sensilla on the palps respond to shifts in RH. Conclusions Our results show that temperature acts synergistically with humidity to increase the rapidity and frequency of the biting response in tsetse above the levels induced by increasing temperature or humidity separately. Palp sensilla housing hygroreceptor cells

  13. Persistence of non-native spore forming bacteria in drinking water biofilm and evaluation of decontamination methods.

    PubMed

    Shane, William T; Szabo, Jeffrey G; Bishop, Paul L

    2011-01-01

    Persistence of Bacillus globigii spores, a surrogate for Bacillus anthracis, was studied on biofouled concrete-lined slides in drinking water using biofilm annular reactors. Reactors were inoculated with B. globigii spores and persistence was monitored in the bulk and biofilm phases, first in dechlorinated water and later with free chlorine concentrations of 1 and 5 mg/L. In the dechlorinated study, a steady state population of spores developed on the slides. The addition of free chlorine at 5 mg/L decreased the adhered spore density by 2-logs within 4 hours and spores were not detected after 67 and 49 hours in the presence of 1 and 5 mg/L free chlorine, respectively. This suggests that adhered spores can persist in non-chlorinated conditions, but detach and/or are inactivated upon addition of free chlorine. When injected into a chlorinated reactor, adhered spore density continually decreased and spores were either undetectable or unquantifiable by 48 hours for both 1 and 5 mg/L chlorine concentrations. Results from these experiments suggest that the presence of a free chlorine residual limits adherence of viable spores to biofouled concrete-lined pipe walls by inactivating spores before they have attached. Both free chlorine concentrations (1 and 5 mg/L) were equally effective at inactivating spores in terms of log reduction, but the higher concentrations yielded faster rates of log reduction.

  14. Persistent organic contaminants and steroid hormones levels in Morelet's crocodiles from the Southern Gulf of Mexico.

    PubMed

    Gonzalez-Jauregui, Mauricio; Valdespino, Carolina; Salame-Méndez, Arturo; Aguirre-León, Gustavo; Rendón-Vonosten, Jaime

    2012-04-01

    Effects of endocrine disruptors on reproductive variables of top predators, such as alligators and crocodiles, have long been cited. Due to their long life span, these predators provide us with historic contaminant annals. In this study we tried to test whether lifestyle (free-ranging vs. farm animals) and reproductive age of Morelet's crocodiles in Campeche, Mexico, affect the bioaccumulation of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). Subsequently, we tested to see whether their concentration was related to steroid hormones (testosterone and estradiol-17β) levels once normal cyclic hormone variation and reproductive age had been taken into account. From the group of contaminants considered (analyzed as families), only frequency of hexachlorocyclohexanes (∑HCH) and ∑PCB permitted analyses. Whereas there was a greater concentration of ∑HCH bioaccumulated by free-ranging crocodiles, ∑PCB was found in equal quantities in free-ranging and farm animals. No difference was observed in relation to reproductive age for any of the contaminants. However, ∑PCB concentrations were related to testosterone levels among female crocodiles. This androgenic effect of ∑PCB has not been reported previously. Because testosterone promotes aggressive behavior in vertebrates, excessive aggression during the estrous season, or when female crocodiles should be caring for their young, could result in reproductive failure in Morelet's crocodiles and potential long-term decline of the population.

  15. Persistent brominated and chlorinated dioxin blood levels in a chemist. 35 years after dioxin exposure

    SciTech Connect

    Schecter, A.; Ryan, J.J. )

    1992-07-01

    This is the first report on occupational health hazards to dioxin chemists associated with laboratory exposure to 2,3,7,8-tetrabromodibenzodioxin (TBrDD), and further characterizes the human response to 2,3,7,8 tetrachlorodibenzodioxin (TCDD). In this case study the chemist was exposed on two separate occasions. In March 1956, after synthesizing 10 g of TBrDD, the chemist suffered from mild and transient chloracne of the neck and wrists; in September 1956, after synthesizing 16 g of TCDD, he suffered severe chloracne of the entire body, headaches, backache, and leg pain on exertion. His measured 2,3,7,8-TBrDD in 1991 was 625 parts per trillion (ppt) in whole blood lipid, 35 years after initial exposure and 18 ppt TCDD, an elevated level in comparison with the mean 2,3,7,8-TCDD level of 5 ppt in the US population. This is the first reported detection of a brominated dioxin in human tissue. The total halogenated dioxin body burden in September 1956 is estimated to have been between 13,005 ppt and 146,726 ppt. This amount can be considered to be, at least in this person, a strong chloracnegenic dose, and a dose causing human nervous system and muscular or circulatory system responses. This uptake demonstrates an occupational hazard to chemists and chemical workers, and the usefulness of human tissue dioxin measurements to document absorption.

  16. Genetic redundancy and persistence of plasmid-mediated trimethoprim/sulfamethoxazole resistant effluent and stream water Escherichia coli.

    PubMed

    Suhartono, Suhartono; Savin, Mary; Gbur, Edward E

    2016-10-15

    Antibiotic resistant bacteria may persist in effluent receiving surface water in the presence of low (sub-inhibitory) antibiotic concentrations if the bacteria possess multiple genes encoding resistance to the same antibiotic. This redundancy of antibiotic resistance genes may occur in plasmids harboring conjugation and mobilization (mob) and integrase (intI) genes. Plasmids extracted from 76 sulfamethoxazole-trimethoprim resistant Escherichia coli originally isolated from effluent and an effluent-receiving stream were used as DNA template to identify sulfamethoxazole (sul) and trimethoprim (dfr) resistances genes plus detect the presence of intI and mob genes using PCR. Sulfamethoxazole and trimethoprim resistance was plasmid-mediated with three sul (sul1, sul2 and sul3 genes) and four dfr genes (dfrA12, dfrA8, dfrA17, and dfrA1 gene) the most prevalently detected. Approximately half of the plasmids carried class 1 and/or 2 integron and, although unrelated, half were also transmissible. Sampling site in relationship to effluent input significantly affected the number of intI and mob but not the number of sul and dfr genes. In the presence of low (sub-inhibitory) sulfamethoxazole concentration, isolates persisted regardless of integron and mobilization gene designation, whereas in the presence of trimethoprim, the presence of both integron and mobilization genes made isolates less persistent than in the absence of both or the presence of a gene from either group individually. Regardless, isolates persisted in large concentrations throughout the experiment. Treated effluent containing antibiotic resistant bacteria may be an important source of integrase and mobilization genes into the stream environment. Sulfamethoxazole-trimethoprim resistant bacteria may have a high degree of genetic redundancy and diversity carrying resistance to each antibiotic, although the role of integrase and mobilization genes towards persistence is unclear. PMID:27455416

  17. Contamination by persistent organochlorines in cetaceans incidentally caught along Brazilian coastal waters.

    PubMed

    Kajiwara, N; Matsuoka, S; Iwata, H; Tanabe, S; Rosas, F C W; Fillmann, G; Readman, J W

    2004-01-01

    Wide ranges of organochlorine residues were determined in the blubber of franciscana (Pontoporia blainvillei), estuarine dolphin (Sotalia guianensis), Atlantic spotted dolphin (Stenella frontalis), and long-beaked common dolphin (Delphinus capensis) incidentally caught along Brazilian coastal waters. Concentrations of DDTs and PCBs were the highest, followed by CHLs, TCPMOH, dieldrin, TCPMe, heptachlor epoxide, HCB, and HCHs. Unexpectedly, significant pollution of PCBs, DDTs, TCPMe, and TCPMOH were observed in cetaceans from Brazil, implying the occurrence of local sources in the Southern Hemisphere comparable to those in the Northern Hemisphere, probably by high industrialization in Brazil. On the other hand, CHLs, HCB, HCHs, heptachlor epoxide, and dieldrin residue levels in Brazilian dolphins were much lower than those in other species from the Northern Hemisphere. Significant correlations of TCPMe and TCPMOH were found along with PCBs and DDTs, indicating the highly bioaccumulative nature of all these compounds and/or possible similar pollution sources. PMID:15025172

  18. Persistent organochlorines in 13 shark species from offshore and coastal waters of Korea: Species-specific accumulation and contributing factors.

    PubMed

    Lee, Hyun-Kyung; Jeong, Yunsun; Lee, Sunggyu; Jeong, Woochang; Choy, Eun-Jung; Kang, Chang-Keun; Lee, Won-Chan; Kim, Sang-Jo; Moon, Hyo-Bang

    2015-05-01

    Data on persistent organochlorines (OCs) in sharks are scarce. Concentrations of OCs such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in the muscle tissue of 13 shark species (n=105) collected from offshore (Indian and Pacific Oceans) and coastal waters of Korea, to investigate species-specific accumulation of OCs and to assess the potential health risks associated with consumption of shark meat. Overall OC concentrations were highly variable not only among species but also within the same species of shark. The concentrations of PCBs, DDTs, chlordanes, hexachlorobenzene, and heptachlor in all shark species ranged from levels of OCs. Inter-species differences in the concentrations and accumulation profiles of OCs among shark species could be explained by differences in feeding habit and sampling locations. Several confounding factors such as growth velocity, trophic position, and regional contamination status may affect the bioaccumulation of OCs in sharks. Hazard ratios of non-cancer risk for all the OCs were below one, whereas the hazard ratios of lifetime cancer risks of PCBs and DDTs exceeded one, implying potential carcinogenic effects in the general population in Korea. This is the first report to document the occurrence of OCs in sharks from Korea.

  19. Persistent DNA damage caused by low levels of mitomycin C induces irreversible cell senescence.

    PubMed

    McKenna, Elise; Traganos, Frank; Zhao, Hong; Darzynkiewicz, Zbigniew

    2012-08-15

    Mutations of oncogenes and tumor suppressor genes which activate mTOR through several downstream signaling pathways are common to cancer. Activation of mTOR when combined with inhibition of cell cycle progression or DNA replication stress has previously been shown to promote cell senescence. In the present study, we examined the conditions under which human non-small cell lung carcinoma A549 cells can undergo senescence when treated with the DNA alkylating agent mitomycin C (MMC). While exposure of A549 cells to 0.1 or 0.5 µg/ml of MMC led to their arrest in S phase of the cell cycle and subsequent apoptosis, exposure to 0.01 or 0.02 µg/ml for 6 d resulted in induction of cell senescence and near total (0.01 µg/ml) or total (0.02 µg/ml) elimination of their reproductive potential. During exposure to these low concentrations of MMC, the cells demonstrated evidence of DNA replication stress manifested by expression of γH2AX, p21 (WAF1) and a very low level of EdU incorporation into DNA. The data are consistent with the notion that enduring DNA replication stress in cells known to have activated oncogenes leads to their senescence. It is reasonable to expect that tumors having constitutive activation of oncogenes triggering mTOR signaling may be particularly predisposed to undergoing senescence following prolonged treatment with low doses of DNA damaging drugs. PMID:22871735

  20. Drought-trigger ground-water levels and analysis of historical water-level trends in Chester County, Pennsylvania

    USGS Publications Warehouse

    Schreffler, Curtis L.

    1996-01-01

    The Chester County observation-well network was established in 1973 through a cooperative agreement between the Chester County Water Resources Authority (CCWRA) and the U.S. Geological Survey. The network was established to monitor local ground-water levels, to determine drought conditions, and to monitor ground-water-level trends. Drought-warning and drought-emergency water-level triggers were determined for 20 of the 23 wells in the Chester County observation-well network. A statistical test to determine either rising or declining water-level trends was performed on data for all wells in the network. Water-level data from both of these wells showed a rising trend. A decrease in ground-water pumping in the area near these wells was probably the reason for the rise in water levels.

  1. Water levels in the Yucca Mountain area, Nevada, 1993

    SciTech Connect

    Tucci, P.; Goemaat, R.L.; Burkhardt, D.J.

    1996-07-01

    Water levels were monitored in 28 wells in the Yucca Mountain area, Nevada, during 1993. Seventeen wells were monitored periodically, generally on a monthly basis, and 11 wells representing 18 intervals were monitored hourly. All wells monitor water levels in Tertiary volcanic rocks, except one that monitors water levels in Paleozoic carbonate rocks. Water levels were measured using calibrated steel tapes and pressure transducers; steel-tape measurements were corrected for mechanical stretch, thermal expansion, and borehole deviation to obtain precise water-level altitudes. Water-level altitudes in the Tertiary volcanic rocks ranged from about 728 meters above sea level east of Yucca Mountain to about 1,034 meters above sea level north of Yucca Mountain. Water-level altitudes in the well monitoring the Paleozoic carbonate rocks varied between 752 and 753 meters above sea level during 1993. Water levels were an average of about 0.04 meter lower than 1992 water levels. All data were acquired in accordance with a quality-assurance program to support the reliability of the data.

  2. Predicting persistence of asthma in preschool wheezers: crystal balls or muddy waters?

    PubMed

    Fouzas, Sotirios; Brand, Paul L P

    2013-03-01

    Since preschool wheezing is the common expression of several heterogeneous disorders, identification of children at risk for persistent asthma is particularly challenging. To date, efforts to predict the outcome of preschool wheeze have mainly relied on predictive rules consisting of simple clinical and laboratory parameters. Among these tools, the asthma predictive index (API) has been introduced in international guidelines and position papers and is recommended for use in clinical practice. This article reviews the currently available asthma predictive models focusing on their validity and performance characteristics. Although these tools are generally simple and easy to apply, they suffer important intrinsic and practical limitations and they have been insufficiently validated to allow for widespread use in clinical settings. We also present evidence that their ability to predict the long-term outcome of preschool wheeze is limited in general populations, and even poorer in high-risk children in which prediction of asthma persistence might have important clinical and prognostic implications. Due to the complex and multifactorial nature of asthma, prediction of asthma persistence based on simple clinical models is practically impossible. PMID:23347660

  3. Levels, fluxes and time trends of persistent organic pollutants in Lake Thun, Switzerland: combining trace analysis and multimedia modeling.

    PubMed

    Bogdal, Christian; Scheringer, Martin; Schmid, Peter; Bläuenstein, Markus; Kohler, Martin; Hungerbühler, Konrad

    2010-08-01

    Levels, mass fluxes, and time trends of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in Lake Thun, a peri-Alpine lake, are investigated. We present measurements of PBDEs and PCBs in air, lake water, lake sediment, and tributary water. These measurements are combined with a multimedia fate model, based on site-specific environmental parameters from the lake catchment. Measured loadings of PBDEs and PCBs in air and tributaries were used to drive the model. The model satisfactorily reproduces PBDE and PCB congener patterns in water and sediment, but it tends to yield concentrations in water below the measurements and concentrations in sediment exceeding the measurements. A sensitivity analysis reveals that partitioning of PBDEs and PCBs between the aqueous dissolved phase and suspended particulate matter in the water column strongly affects the model results, in particular the concentrations in water and sediment. For lower-brominated PBDEs, approximately 70% and 30% of input into the lake stems from atmospheric deposition and from tributaries, respectively. For heavier PBDEs and all PCBs, rivers appear to deliver the major load (64-92%). Waste water effluents are of minor importance. 50-90% of the total input is buried in the permanent sediment. Sediment burial makes PBDEs and PCBs less available for recycling in the environment, and reduces concentrations in the outflowing river. If use of deca-BDE increases in the future, levels in Lake Thun will follow the same trend. If the use and resulting environmental emissions decrease, concentrations in water will rapidly decline, according to our calculations, while sediment levels will decrease at a considerably slower rate.

  4. Persistently elevated soluble tumor necrosis factor receptor and interleukin-1 receptor antagonist levels in critically ill patients.

    PubMed

    Rogy, M A; Coyle, S M; Oldenburg, H S; Rock, C S; Barie, P S; Van Zee, K J; Smith, C G; Moldawer, L L; Lowry, S F

    1994-02-01

    The appearance of endogenously produced inhibitors against tumor necrosis factor (TNF) (soluble TNF-receptor type I, sTNFR-I) and interleukin-1 (IL-1 receptor antagonist, IL-1ra) was evaluated acutely in five normal patients after experimental endotoxemia lipopolysaccharide (LPS) and prospectively during a one to 11 week period in 12 septic, critically ill patients. Increased levels of both factors remained detectable in the circulation for up to 24 hours after LPS (2 nanograms per kilogram body weight) administration in normal patients. Despite free TNF-a activity being detected only sporadically (3 percent of the samples) and that IL-1 beta was never detectable in the patients in the intensive care unit, IL-6 bioactivity was present in 90 percent of initial samples. Circulating sTNFR-I levels up to 62,000 picograms per milliliter and IL-1ra levels of 14,800 picograms per milliliter were noted in the critically ill patients and remained consistently detectable throughout the extended period of evaluation. While there was no difference in IL-1ra levels between patients who survived or ultimately died, sTNFR-I levels were significantly (p < 0.001) lower in survivors compared with nonsurvivors. A correlation between circulating sTNFR-I and concurrent cortisol levels (r = 0.64; p < 0.002) was also noted. Furthermore, a correlation between sTNFR-I and the severity of initial insult, as assessed by APACHE II scores (r = 0.54; p < 0.01) was demonstrable. These naturally occurring cytokine antagonists likely represent additional indicators of the presence of an infectious or other inflammatory process and seem to persist in the circulation even during conditions in which their respective proinflammatory cytokines are not demonstrable. PMID:8173722

  5. Seabird feathers as monitors of the levels and persistence of heavy metal pollution after the Prestige oil spill.

    PubMed

    Moreno, Rocío; Jover, Lluís; Diez, Carmen; Sanpera, Carola

    2011-10-01

    We measured heavy metal concentrations in yellow-legged gulls (n = 196) and European shags (n = 189) in order to assess the temporal pattern of contaminant exposure following the Prestige oil spill in November 2002. We analysed Pb, Cu, Zn, Cr, Ni and V levels in chick feathers sampled at four colonies during seven post-spill years (2003-2009), and compared results with pre-spill levels obtained from feathers of juvenile shag corpses (grown in spring/summer 2002). Following the Prestige wreck, Cu (4.3-10 μg g(-1)) and Pb concentrations (1.0-1.4 μg g(-1)) were, respectively, between two and five times higher than pre-spill levels (1.5-3.6 and 0.1-0.4 μg g(-1)), but returned to previous background concentrations after three years. Our study highlights the suitability of chick feathers of seabirds for assessing the impact of oil spills on heavy metal contamination, and provides the best evidence to date on the persistence of oil pollution after the Prestige incident.

  6. Persistent organic pollutant levels and the importance of source proximity in Baltic and Svalbard breeding common eiders.

    PubMed

    Fenstad, Anette A; Jenssen, Bjørn M; Gabrielsen, Kristin M; Öst, Markus; Jaatinen, Kim; Bustnes, Jan O; Hanssen, Sveinn A; Moe, Børge; Herzke, Dorte; Krøkje, Åse

    2016-06-01

    The distance to sources and the long-range transport potential of persistent organic pollutants (POPs) are important in understanding the impact of anthropogenic pollution on natural seabird populations. The present study documented blood concentrations of POPs in the Baltic Sea (Tvärminne, Finland) population of common eiders (Somateria mollissima) in 2009 and in 2011 and compared the concentrations with the presumably less exposed Arctic population in Svalbard (Kongsfjorden, Norway). The Baltic population had 26, 10, and 5 times greater concentrations of hexachlorocyclohexane, polychlorinated biphenyls, and p,p'-dichlorodiphenyldichloroethylene than the Svalbard population. Unexpectedly, concentrations of chlordanes were higher in Svalbard eiders, whereas concentrations of hexachlorobenzenes (HCBs) did not differ between the 2 populations. Although the similar HCB levels may partly be explained by the high transport potential of HCBs, unknown factors may have been more important than distance to sources and long-range transport potential for the chlordanes. One plausible explanation may be that the fasting-related redistribution of POPs from fat to blood was greater throughout the incubation in Arctic eiders, causing them to have higher blood levels of these POPs at the end of incubation. The blood concentrations of POPs in Baltic eiders were higher than documented in any other eider population and were comparable to levels in seabirds feeding at higher trophic positions in the food chain. Environ Toxicol Chem 2016;35:1526-1533. © 2015 SETAC. PMID:26553455

  7. 26. Mechanical float gages used to monitor level of water ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Mechanical float gages used to monitor level of water in the filtration bed reservoir. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  8. Multimedia level-III partitioning and residence times of xenobiotics in water-rich and water-poor environments

    SciTech Connect

    Breitkopf, C.; Kuehne, R.; Schueuermann, G.

    2000-05-01

    The environmental fate of 10 compounds covering a wide range of intrinsic persistence and volatility is studied with a multimedia level-III fugacity model at two system temperatures (293 and 282 K) using water-rich and water-poor model environments and standard emission scenarios to air and water, respectively. The resultant level-III partitionings depend significantly on the entry mode and on the relative compartment sizes, and the variation with system temperature is more pronounced for polar compounds and when air is the primary discharge compartment. For example, the steady-state portion in soil of airborne phenol varies from 21 to 89%, whereas waterborne phenol resides in water at a rate of 100% in both water-rich and water-poor environments. For some compounds, the residence time (considering both advection and degradation) is substantially affected by intermedia transport processes such as rainfall. With airborne atrazine, the regional residence time is comparable to that of DDT and significantly greater than the ones of hexachlorobenzene, polychlorinated biphenyl 28, and lindane, although the latter have much longer media-specific half-lives and much greater hydrophobicity. The discussion includes detailed analyses of the compound properties and their impact on the level-III environmental fate.

  9. Genetic variation of foot-and-mouth disease virus isolates recovered from persistently infected water buffalo (Bubalus bubalis).

    PubMed

    Barros, José Júnior F; Malirat, Viviana; Rebello, Moacyr A; Costa, Eliane V; Bergmann, Ingrid E

    2007-02-25

    Genetic variation of foot-and-mouth disease virus (FMDV) isolates, serotype O, recovered serially over a 1-year period from persistently infected buffalos was assessed. The persistent state was established experimentally with plaque-purified FMDV, strain O(1)Campos, in five buffalos (Bubalus bubalis). Viral isolates collected from esophageal-pharyngeal (EP) fluids for up to 71 weeks after infection were analyzed at different times by nucleotide sequencing and T(1) RNase oligonucleotide fingerprinting to assess variability in the VP1-coding region and in the complete genome, respectively. Genetic variation increased, although irregularly, with time after infection. The highest values observed for the VP1-coding region and for the whole genome were 2.5% and 1.8%, respectively. High rates of fixation of mutations were observed using both methodologies, reaching values of 0.65 substitutions per nucleotide per year (s/nt/y) and 0.44s/nt/y for nucleotide sequencing and oligonucleotide fingerprinting, respectively, when selected samples recovered at close time periods were analyzed. The data herein indicate that complex mixtures of genotypes may arise during FMDV type O persistent infection in water buffalos, which can act as viral reservoirs and also represent a potential source of viral variants. These results fit within the quasi-species dynamics described for FMDV, in which viral populations are constituted by related, non-identical genomes that evolve independently from each other, and may predominate at a given time.

  10. Mycobacterium Lysine ε-aminotransferase is a novel alarmone metabolism related persister gene via dysregulating the intracellular amino acid level.

    PubMed

    Duan, Xiangke; Li, Yunsong; Du, Qinglin; Huang, Qinqin; Guo, Siyao; Xu, Mengmeng; Lin, Yanping; Liu, Zhidong; Xie, Jianping

    2016-01-01

    Bacterial persisters, usually slow-growing, non-replicating cells highly tolerant to antibiotics, play a crucial role contributing to the recalcitrance of chronic infections and treatment failure. Understanding the molecular mechanism of persister cells formation and maintenance would obviously inspire the discovery of new antibiotics. The significant upregulation of Mycobacterium tuberculosis Rv3290c, a highly conserved mycobacterial lysine ε-aminotransferase (LAT) during hypoxia persistent model, suggested a role of LAT in persistence. To test this, a lat deleted Mycobacterium smegmatis was constructed. The expression of transcriptional regulator leucine-responsive regulatory protein (LrpA) and the amino acids abundance in M. smegmatis lat deletion mutants were lowered. Thus, the persistence capacity of the deletion mutant was impaired upon norfloxacin exposure under nutrient starvation. In summary, our study firstly reported the involvement of mycobacterium LAT in persister formation, and possibly through altering the intracellular amino acid metabolism balance. PMID:26806099

  11. Impact of sea-level rise on sea water intrusion in coastal aquifers.

    PubMed

    Werner, Adrian D; Simmons, Craig T

    2009-01-01

    Despite its purported importance, previous studies of the influence of sea-level rise on coastal aquifers have focused on specific sites, and a generalized systematic analysis of the general case of the sea water intrusion response to sea-level rise has not been reported. In this study, a simple conceptual framework is used to provide a first-order assessment of sea water intrusion changes in coastal unconfined aquifers in response to sea-level rise. Two conceptual models are tested: (1) flux-controlled systems, in which ground water discharge to the sea is persistent despite changes in sea level, and (2) head-controlled systems, whereby ground water abstractions or surface features maintain the head condition in the aquifer despite sea-level changes. The conceptualization assumes steady-state conditions, a sharp interface sea water-fresh water transition zone, homogeneous and isotropic aquifer properties, and constant recharge. In the case of constant flux conditions, the upper limit for sea water intrusion due to sea-level rise (up to 1.5 m is tested) is no greater than 50 m for typical values of recharge, hydraulic conductivity, and aquifer depth. This is in striking contrast to the constant head cases, in which the magnitude of salt water toe migration is on the order of hundreds of meters to several kilometers for the same sea-level rise. This study has highlighted the importance of inland boundary conditions on the sea-level rise impact. It identifies combinations of hydrogeologic parameters that control whether large or small salt water toe migration will occur for any given change in a hydrogeologic variable.

  12. Impact of sea-level rise on sea water intrusion in coastal aquifers.

    PubMed

    Werner, Adrian D; Simmons, Craig T

    2009-01-01

    Despite its purported importance, previous studies of the influence of sea-level rise on coastal aquifers have focused on specific sites, and a generalized systematic analysis of the general case of the sea water intrusion response to sea-level rise has not been reported. In this study, a simple conceptual framework is used to provide a first-order assessment of sea water intrusion changes in coastal unconfined aquifers in response to sea-level rise. Two conceptual models are tested: (1) flux-controlled systems, in which ground water discharge to the sea is persistent despite changes in sea level, and (2) head-controlled systems, whereby ground water abstractions or surface features maintain the head condition in the aquifer despite sea-level changes. The conceptualization assumes steady-state conditions, a sharp interface sea water-fresh water transition zone, homogeneous and isotropic aquifer properties, and constant recharge. In the case of constant flux conditions, the upper limit for sea water intrusion due to sea-level rise (up to 1.5 m is tested) is no greater than 50 m for typical values of recharge, hydraulic conductivity, and aquifer depth. This is in striking contrast to the constant head cases, in which the magnitude of salt water toe migration is on the order of hundreds of meters to several kilometers for the same sea-level rise. This study has highlighted the importance of inland boundary conditions on the sea-level rise impact. It identifies combinations of hydrogeologic parameters that control whether large or small salt water toe migration will occur for any given change in a hydrogeologic variable. PMID:19191886

  13. Calculating the Diffusive Flux of Persistent Organic Pollutants between Sediments and the Water Column on the Palos Verdes Shelf Superfund Site using Polymeric Passive Samplers

    EPA Science Inventory

    Passive samplers were used to determine water concentrations of persistent organic pollutants (POPs) in the surface sediments and near-bottom water of a marine Superfund site on the Palos Verdes Shelf, California, USA. Measured concentrations in the porewater and water column at...

  14. Persistent Exposure to Arsenic via Drinking Water in Rural Bangladesh Despite Major Mitigation Efforts

    PubMed Central

    Gardner, Renee; Hamadani, Jena; Grandér, Margaretha; Tofail, Fahmida; Nermell, Barbro; Palm, Brita; Kippler, Maria

    2011-01-01

    Objectives. Elevated arsenic levels in tube-well water in Bangladesh have prompted extensive mitigation projects. We evaluated the effectiveness of long-term mitigation efforts by longitudinally measuring arsenic exposure in pregnant women and their children, the most susceptible population groups. Methods. The study was nested in a population-based nutrition intervention in Matlab, Bangladesh. Mother–child pairs (n = 1951) were followed from 2001 to 2003, beginning in early gestation and continuing to 5 years postpartum. We measured arsenic concentrations in urine (U-As) of the 5-year-old children by using high-performance liquid chromatography online with hydride generation and inductively coupled plasma mass spectrometry and compared them with earlier childhood U-As and maternal U-As during pregnancy. Results. Children had elevated U-As at 5 years old (median = 51 μg/L, 5th–95th percentiles = 16–355 μg/L), and U-As distribution was similar to that observed in the mothers during gestation. Children's U-As at 5 years old significantly correlated with their U-As at 1.5 years old and to maternal U-As during early and late gestation. Conclusions. Despite major mitigation efforts, arsenic exposure remains highly elevated in rural Bangladesh. Further mitigation strategies are required and must be rigorously evaluated for long-term efficacy. PMID:21778503

  15. Persistence of Low Pathogenic Influenza A Virus in Water: A Systematic Review and Quantitative Meta-Analysis

    PubMed Central

    Dalziel, Antonia E.; Delean, Steven; Heinrich, Sarah; Cassey, Phillip

    2016-01-01

    Avian influenza viruses are able to persist in the environment, in-between the transmission of the virus among its natural hosts. Quantifying the environmental factors that affect the persistence of avian influenza virus is important for influencing our ability to predict future outbreaks and target surveillance and control methods. We conducted a systematic review and quantitative meta-analysis of the environmental factors that affect the decay of low pathogenic avian influenza virus (LPAIV) in water. Abiotic factors affecting the persistence of LPAIV have been investigated for nearly 40 years, yet published data was produced by only 26 quantitative studies. These studies have been conducted by a small number of principal authors (n = 17) and have investigated a narrow range of environmental conditions, all of which were based in laboratories with limited reflection of natural conditions. The use of quantitative meta-analytic techniques provided the opportunity to assess persistence across a greater range of conditions than each individual study can achieve, through the estimation of mean effect-sizes and relationships among multiple variables. Temperature was the most influential variable, for both the strength and magnitude of the effect-size. Moderator variables explained a large proportion of the heterogeneity among effect-sizes. Salinity and pH were important factors, although future work is required to broaden the range of abiotic factors examined, as well as including further diurnal variation and greater environmental realism generally. We were unable to extract a quantitative effect-size estimate for approximately half (50.4%) of the reported experimental outcomes and we strongly recommend a minimum set of quantitative reporting to be included in all studies, which will allow robust assimilation and analysis of future findings. In addition we suggest possible means of increasing the applicability of future studies to the natural environment, and

  16. Oil-in-Water Emulsion MF59 Increases Germinal Center B Cell Differentiation and Persistence in Response to Vaccination.

    PubMed

    Lofano, Giuseppe; Mancini, Francesca; Salvatore, Giulia; Cantisani, Rocco; Monaci, Elisabetta; Carrisi, Corrado; Tavarini, Simona; Sammicheli, Chiara; Rossi Paccani, Silvia; Soldaini, Elisabetta; Laera, Donatello; Finco, Oretta; Nuti, Sandra; Rappuoli, Rino; De Gregorio, Ennio; Bagnoli, Fabio; Bertholet, Sylvie

    2015-08-15

    Induction of persistent protective immune responses is a key attribute of a successful vaccine formulation. MF59 adjuvant, an oil-in-water emulsion used in human vaccines, is known to induce persistent high-affinity functional Ab titers and memory B cells, but how it really shapes the Ag-specific B cell compartment is poorly documented. In this study, we characterized the Ab- and Ag-specific B cell compartment in wild-type mice immunized with HlaH35L, a Staphylococcus aureus Ag known to induce measurable functional Ab responses, formulated with MF59 or aluminum salts, focusing on germinal centers (GC) in secondary lymphoid organs. Taking advantage of single-cell flow cytometry analyses, HlaH35L-specific B cells were characterized for the expression of CD38 and GL-7, markers of memory and GC, respectively, and for CD80 and CD73 activation markers. We demonstrated that immunization with MF59-, but not aluminum salt-adjuvanted HlaH35L, induced expanded Ag-specific CD73(+)CD80(-) GC B cells in proximal- and distal-draining lymph nodes, and promoted the persistence of GC B cells, detected up to 4 mo after immunization. In addition to increasing GC B cells, MF59-adjuvanted HlaH35L also increased the frequency of T follicular helper cells. This work extends previous knowledge regarding adaptive immune responses to MF59-adjuvanted vaccines, and, to our knowledge, for the first time an adjuvant used in human licensed products is shown to promote strong and persistent Ag-specific GC responses that might benefit the rational design of new vaccination strategies. PMID:26170383

  17. Oil-in-Water Emulsion MF59 Increases Germinal Center B Cell Differentiation and Persistence in Response to Vaccination.

    PubMed

    Lofano, Giuseppe; Mancini, Francesca; Salvatore, Giulia; Cantisani, Rocco; Monaci, Elisabetta; Carrisi, Corrado; Tavarini, Simona; Sammicheli, Chiara; Rossi Paccani, Silvia; Soldaini, Elisabetta; Laera, Donatello; Finco, Oretta; Nuti, Sandra; Rappuoli, Rino; De Gregorio, Ennio; Bagnoli, Fabio; Bertholet, Sylvie

    2015-08-15

    Induction of persistent protective immune responses is a key attribute of a successful vaccine formulation. MF59 adjuvant, an oil-in-water emulsion used in human vaccines, is known to induce persistent high-affinity functional Ab titers and memory B cells, but how it really shapes the Ag-specific B cell compartment is poorly documented. In this study, we characterized the Ab- and Ag-specific B cell compartment in wild-type mice immunized with HlaH35L, a Staphylococcus aureus Ag known to induce measurable functional Ab responses, formulated with MF59 or aluminum salts, focusing on germinal centers (GC) in secondary lymphoid organs. Taking advantage of single-cell flow cytometry analyses, HlaH35L-specific B cells were characterized for the expression of CD38 and GL-7, markers of memory and GC, respectively, and for CD80 and CD73 activation markers. We demonstrated that immunization with MF59-, but not aluminum salt-adjuvanted HlaH35L, induced expanded Ag-specific CD73(+)CD80(-) GC B cells in proximal- and distal-draining lymph nodes, and promoted the persistence of GC B cells, detected up to 4 mo after immunization. In addition to increasing GC B cells, MF59-adjuvanted HlaH35L also increased the frequency of T follicular helper cells. This work extends previous knowledge regarding adaptive immune responses to MF59-adjuvanted vaccines, and, to our knowledge, for the first time an adjuvant used in human licensed products is shown to promote strong and persistent Ag-specific GC responses that might benefit the rational design of new vaccination strategies.

  18. Hydrologic effects on water level changes associated with episodic fault creep near Parkfield, California

    USGS Publications Warehouse

    Roeloffs, E.A.; Burford, S.S.; Riley, F.S.; Records, A.W.

    1989-01-01

    As part of the Parkfield, California, earthquake prediction experiment, water level is monitored in a well 460 m from the main trace of the San Andreas fault on Middle Mountain, in the preparation zone of the anticipated Parkfield earthquake. The well configuration allows water level to be monitored in two fluid reservoirs at depths of 85 and 250 m below land surface. During 1987, water level changes were recorded during 12 of the 18 episodes of accelerated fault creep detected by a creep meter spanning the fault trace 750 m northwest of the well. The creep-related water level changes in the shallow reservoir have durations of less than 1 day, whereas in the deeper reservoir the changes persist for as long as 2 months. These data suggest that the transient nature of the water level changes in the shallow interval is due to vertical flow to the water table and is not evidence that creep events propagate past the well. -from Authors

  19. Persistence, variance and toxic levels of organochlorine pesticides in fluvial sediments and the role of black carbon in their retention.

    PubMed

    Parween, Musarrat; Ramanathan, Al; Khillare, P S; Raju, N J

    2014-05-01

    The present study assesses the persistence and variation of organochlorine pesticides (OCPs) and their regulation by total organic carbon (TOC) and black carbon (BC) in freshwater sediment. Sediment samples from the Yamuna River, a major tributary of the Ganges (one of the most populated and intensively used rivers in Asia), had high levels of Σ20OCPs (21.41 to 139.95 ng g(-1)). β-Hexachlorocyclohexane (β-HCH) was the most predominant component. ΣHCH and Σdichloro-diphenyl-trichloroethane (DDT) constituted ~86% of Σ20OCPs. Isomer ratios indicated fresh usage of lindane, DDT and technical-grade HCH. Toxicological comparison with freshwater sediment quality guidelines showed γ-HCH and DDT at high levels of concern. β-HCH, α-HCH, endrin, heptachlor epoxide, dichloro-diphenyl-dichloroethane (DDD), dichloro-diphenyl-dichloroethylene and chlordane were above some of the guideline levels. TOC and BC had mean concentrations of 1.37 ± 0.51% and 0.46 ± 0.23 mg g(-1), respectively. BC constituted 1.25 to 10.56% of TOC. We observed low to moderate correlations of BC with isomers of HCH, p,p'-DDT and methoxychlor while of TOC with Σ20OCPs, γ-HCH, endosulfan sulfate and methoxychlor. Principal component analysis enabled correlating and clustering of various OCPs, BC and TOC. OCP distribution was related with pH, electrical conductivity, soil moisture and finer fractions of sediment. OCPs with similarity in properties that determine their interactions with carbonaceous components of sediment clustered together. A number of factors may, thus, be involved in the regulation of interactive forces between BC and OCPs. BC in this study may be more important than TOC in the retention of some OCPs into fluvial sediments, thereby reducing their bioavailability. The finding is probably the first of its kind to report and emphasises the role of BC in the persistence of OCPs in fluvial sediments. PMID:24488553

  20. Persistence, variance and toxic levels of organochlorine pesticides in fluvial sediments and the role of black carbon in their retention.

    PubMed

    Parween, Musarrat; Ramanathan, Al; Khillare, P S; Raju, N J

    2014-05-01

    The present study assesses the persistence and variation of organochlorine pesticides (OCPs) and their regulation by total organic carbon (TOC) and black carbon (BC) in freshwater sediment. Sediment samples from the Yamuna River, a major tributary of the Ganges (one of the most populated and intensively used rivers in Asia), had high levels of Σ20OCPs (21.41 to 139.95 ng g(-1)). β-Hexachlorocyclohexane (β-HCH) was the most predominant component. ΣHCH and Σdichloro-diphenyl-trichloroethane (DDT) constituted ~86% of Σ20OCPs. Isomer ratios indicated fresh usage of lindane, DDT and technical-grade HCH. Toxicological comparison with freshwater sediment quality guidelines showed γ-HCH and DDT at high levels of concern. β-HCH, α-HCH, endrin, heptachlor epoxide, dichloro-diphenyl-dichloroethane (DDD), dichloro-diphenyl-dichloroethylene and chlordane were above some of the guideline levels. TOC and BC had mean concentrations of 1.37 ± 0.51% and 0.46 ± 0.23 mg g(-1), respectively. BC constituted 1.25 to 10.56% of TOC. We observed low to moderate correlations of BC with isomers of HCH, p,p'-DDT and methoxychlor while of TOC with Σ20OCPs, γ-HCH, endosulfan sulfate and methoxychlor. Principal component analysis enabled correlating and clustering of various OCPs, BC and TOC. OCP distribution was related with pH, electrical conductivity, soil moisture and finer fractions of sediment. OCPs with similarity in properties that determine their interactions with carbonaceous components of sediment clustered together. A number of factors may, thus, be involved in the regulation of interactive forces between BC and OCPs. BC in this study may be more important than TOC in the retention of some OCPs into fluvial sediments, thereby reducing their bioavailability. The finding is probably the first of its kind to report and emphasises the role of BC in the persistence of OCPs in fluvial sediments.

  1. Ground-water levels and quality data for Georgia, 1978

    USGS Publications Warehouse

    Clarke, J.S.; Hester, W.G.; O'Byrne, M. P.

    1979-01-01

    Mean water levels in wells across Georgia were from 0.25 foot higher to 11.4 feet lower in 1978 than in 1977, and in some areas were the lowest on record. Water levels in the principal artesian aquifer underwent a long-term decline during the period 1969-78. In some areas water levels dropped more than 10 feet. Wells tapping the Clayton Limestone in the Albany area showed a long-term decline during the period 1969-78, and in some wells water levels dropped more than 20 feet. Water levels in the Cretaceous aquifer system showed little fluctuation during 1978; however, in a well located in Chattahoochee County, water levels declined 4.4 feet during 1969-78. In the Piedmont area mean water levels remained the same to 2.2 feet lower in 1978 than in 1977, and showed no long-term trend. Chloride concentrations in the principal artesian aquifer in the Savannah area remained stable and in the Brunswick area continued to rise during 1978. Daily mean water-level fluctuations and trends for 1978 and fluctuations of the monthly mean water level for the previous 10 years are shown in hydrographs of 33 selected observation wells in Georgia. Chloride concentrations in 11 wells in the Savannah and Brunswick areas are shown in graphs of monthly values over the previous 10 years. A short narrative explains fluctuations and trends in each of the hydrographs and chloride concentration graphs shown. (Woodard-USGS)

  2. PERSPECTIVE FROM WATER LEVEL, SOUTHEAST BY 165 DEGREES. Wright's ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PERSPECTIVE FROM WATER LEVEL, SOUTHEAST BY 165 DEGREES. - Wright's Bridge, Spanning Sugar River, former Boston & Maine Railroad (originally Concord & Claremont Railroad), Claremont, Sullivan County, NH

  3. Water level, specific conductance, and water temperature data, San Francisco Bay, California, for Water Year 2000

    USGS Publications Warehouse

    Buchanan, P.A.

    2002-01-01

    Time series of water-level, specific-conductance, and watertemperature data were collected at seven sites in San Francisco Bay during water year 2000 (October 1, 1999 through September 30, 2000). Water-level data were recorded only at Point San Pablo. Specific-conductance and water-temperature data were recorded at 15-minute intervals at the following locations (Figure 1): • Carquinez Strait at Carquinez Bridge • Napa River at Mare Island Causeway near Vallejo • San Pablo Bay at Petaluma River Channel Marker 9 • San Pablo Strait at Point San Pablo • Central San Francisco Bay at Presidio Military Reservation • Central San Francisco Bay at Pier 24 • South San Francisco Bay at San Mateo Bridge near Foster City.

  4. Association between several persistent organic pollutants and thyroid hormone levels in serum among the pregnant women of Korea.

    PubMed

    Kim, Sunmi; Park, Jeongim; Kim, Hai-Joong; Lee, Jeong Jae; Choi, Gyuyeon; Choi, Sooran; Kim, Sungjoo; Kim, Su Young; Moon, Hyo-Bang; Kim, Sungkyoon; Choi, Kyungho

    2013-09-01

    Persistent organic pollutants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) are of global concern because of their widespread contamination and adverse health effects. Potential endocrine disruption, especially of thyroid status by PCBs has been repeatedly suggested in both experimental and epidemiological studies. However the associations with PBDEs or OCPs have been arguable especially in human populations. We investigated the associations between major groups of POPs and thyroid hormone balances among pregnant women. One hundred five pregnant women at delivery were recruited from four cities of Korea in 2011 and were investigated. Blood samples were collected within a day before delivery. Serum was then analyzed for 19 PCBs, 19 PBDEs, and 19 OCPs, along with five thyroid hormones (free and total T3 and T4, and TSH). Several PCBs such as PCB28, 52, and 118 showed negative associations with T3 or T4. BDE47 and total PBDEs showed significant associations with T3 or T4. For OCPs, dichlorodiphenyltrichloroethanes (DDTs) and hexachlorobenzene (HCB) were generally associated with reduction of T3 or T4. The thyroid hormone levels of all subjects were within the reference range, however exposure to several target POPs were clearly related with potential for disrupting thyroid hormone balance among pregnant women, at the current level of exposure. Although subtle, the changes in thyroid hormones should be seen with caution because even minor changes within pregnant women may have significant consequences especially on sensitive population like fetus. PMID:23928038

  5. Vitamin C intervention may lower the levels of persistent organic pollutants in blood of healthy women - A pilot study.

    PubMed

    Guo, Weihong; Huen, Karen; Park, June-Soo; Petreas, Myrto; Crispo Smith, Sabrina; Block, Gladys; Holland, Nina

    2016-06-01

    Emerging evidence suggests that exposure to endocrine-disrupting chemicals including persistent organic pollutants (POPs) such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) has a long term impact on human health. The goal of this pilot study was to test whether antioxidant intervention by vitamin C supplementation may be a remedial approach to decrease body burden of POPs in humans. Using solid phase extraction coupled with a triple quadrupole mass spectrometer and a gas chromatography high resolution mass spectrometry, we measured 18 PCBs, 7 OCPs, and 5 PBDEs in the blood of 15 healthy California women (8 were obese/overweight and 7 had normal weight) before and after 2 months of vitamin C supplementation (1000 mg/day). We observed higher PBDE levels than PCBs and OCPs, but only PCB and OCP levels were strongly and positively correlated with participant's BMI and age. We also found statistically significant decreases in 6 PCBs (PCB-74, PCB-118, PCB-138, PCB-153, PCB-180, and PCB-187), and 2 OCPs (4,4'-DDE, and 4,4'-DDT), but not PBDEs after vitamin C supplementation. Pending confirmation of this pilot finding in a larger study of both sexes, vitamin C intervention may have important public health implications in protecting health by reducing body burdens of POPs. PMID:27090108

  6. Water levels in the Yucca Mountain area, Nevada, 1994

    SciTech Connect

    Graves, R.P.; Tucci, P.; Goemaat, R.L.

    1996-12-31

    Water levels were monitored in 28 wells in the Yucca Mountain area, Nevada, during 1994. Twelve wells representing 13 intervals were monitored periodically, generally on a monthly basis, 6 wells representing 10 intervals were monitored hourly, and 10 wells representing 13 intervals were monitored both periodically and hourly. All wells monitor water levels in Tertiary volcanic rocks, except one, that monitors water levels in Paleozoic carbonate rocks. Water levels were measured using calibrated steel tapes, a multiconductor cable unit, and pressure transducers. Water-level altitudes in the Tertiary volcanic rocks ranged from about 728 to about 1,034 meters above sea level during 1994. The mean-annual water-level altitude in the well monitoring the Paleozoic carbonate rocks was about 753 meters above sea level during 1994. Water levels were only an average of about 0.01 meters lower than 1993 water levels. All data were acquired in accordance with a quality-assurance program to support the reliability of the data.

  7. Water levels in the Yucca Mountain area, Nevada, 1995

    SciTech Connect

    Graves, R.P.; Goemaat, R.L.

    1998-09-01

    Water levels were monitored in 28 wells in the Yucca Mountain area, Nevada, during 1995. Seventeen wells representing 18 depth intervals were monitored periodically, generally on a monthly basis, 2 wells representing 3 depth intervals were monitored hourly, and 9 wells representing 15 depth intervals were monitored both periodically and hourly. All wells monitor water levels in Tertiary volcanic rocks except one that monitors water levels in Paleozoic carbonate rocks. Water levels were measured using calibrated steel tapes, a multiconductor cable unit, and/or pressure transducers. Mean water-level altitudes in the Tertiary volcanic rocks ranged from about 728 to about 1,034 meters above sea level during 1995. The mean water-level altitude in the well monitoring the Paleozoic carbonate rocks was about 753 meters above sea level during 1995. Mean water level altitudes were only an average of about 0.01 meters higher than 1994 mean water level altitudes. A single-well aquifer test was conducted on well UE-25 WT{number_sign}12 during August and September 1995. Well USW 0-2 was also pumped during October and November 1995, in preparation for single-well aquifer test at that well. All data were acquired in accordance with a quality-assurance program to support the reliability of the data.

  8. Hibernation-associated changes in persistent organic pollutant (POP) levels and patterns in British Columbia grizzly bears (ursus arctos horribilis).

    PubMed

    Christensen, Jennie R; MacDuffee, Misty; Yunker, Mark B; Ross, Peter S

    2007-03-15

    We hypothesized that depleted fat reserves in grizzly bears (Ursus arctos horribilis) following annual hibernation would reveal increases in persistent organic pollutant (POP) concentrations compared to those present in the fall. We obtained fat and hair from British Columbia grizzly bears in early spring 2004 to compare with those collected in fall 2003, with the two tissue types providing contaminant and dietary information, respectively. By correcting for the individual feeding habits of grizzlies using a stable isotope-based approach, we found that polychlorinated biphenyls (sigmaPCBs) increased by 2.21x, polybrominated diphenylethers (sigmaPBDEs) increased by 1.58x, and chlordanes (sigmaCHL) by 1.49x in fat following hibernation. Interestingly, individual POPs elicited a wide range of hibernation-associated concentration effects (e.g., CB-153, 2.25x vs CB-169, 0.00x), resulting in POP pattern convergence in a PCA model of two distinct fall feeding groups (salmon-eating vs non-salmon-eating) into a single spring (post-hibernation) group. Our results suggest that diet dictates contaminant patterns during a feeding phase, while metabolism drives patterns during a fasting phase. This work suggests a duality of POP-associated health risks to hibernating grizzly bears: (1) increased concentrations of some POPs during hibernation; and (2) a potentially prolonged accumulation of water-soluble, highly reactive POP metabolites, since grizzly bears do not excrete during hibernation.

  9. Hibernation-associated changes in persistent organic pollutant (POP) levels and patterns in British Columbia grizzly bears (ursus arctos horribilis).

    PubMed

    Christensen, Jennie R; MacDuffee, Misty; Yunker, Mark B; Ross, Peter S

    2007-03-15

    We hypothesized that depleted fat reserves in grizzly bears (Ursus arctos horribilis) following annual hibernation would reveal increases in persistent organic pollutant (POP) concentrations compared to those present in the fall. We obtained fat and hair from British Columbia grizzly bears in early spring 2004 to compare with those collected in fall 2003, with the two tissue types providing contaminant and dietary information, respectively. By correcting for the individual feeding habits of grizzlies using a stable isotope-based approach, we found that polychlorinated biphenyls (sigmaPCBs) increased by 2.21x, polybrominated diphenylethers (sigmaPBDEs) increased by 1.58x, and chlordanes (sigmaCHL) by 1.49x in fat following hibernation. Interestingly, individual POPs elicited a wide range of hibernation-associated concentration effects (e.g., CB-153, 2.25x vs CB-169, 0.00x), resulting in POP pattern convergence in a PCA model of two distinct fall feeding groups (salmon-eating vs non-salmon-eating) into a single spring (post-hibernation) group. Our results suggest that diet dictates contaminant patterns during a feeding phase, while metabolism drives patterns during a fasting phase. This work suggests a duality of POP-associated health risks to hibernating grizzly bears: (1) increased concentrations of some POPs during hibernation; and (2) a potentially prolonged accumulation of water-soluble, highly reactive POP metabolites, since grizzly bears do not excrete during hibernation. PMID:17410772

  10. Reducing emissions of persistent organic pollutants from a diesel engine by fueling with water-containing butanol diesel blends.

    PubMed

    Chang, Yu-Cheng; Lee, Wen-Jhy; Yang, Hsi-Hsien; Wang, Lin-Chi; Lu, Jau-Huai; Tsai, Ying I; Cheng, Man-Ting; Young, Li-Hao; Chiang, Chia-Jui

    2014-05-20

    The manufacture of water-containing butanol diesel blends requires no excess dehydration and surfactant addition. Therefore, compared with the manufacture of conventional bio-alcohols, the energy consumption for the manufacture of water-containing butanol diesel blends is reduced, and the costs are lowered. In this study, we verified that using water-containing butanol diesel blends not only solves the tradeoff problem between nitrogen oxides (NOx) and particulate matter emissions from diesel engines, but it also reduces the emissions of persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlorinated biphenyls, polychlorinated diphenyl ethers, polybrominated dibenzo-p-dioxins and dibenzofurans, polybrominated biphenyls and polybrominated diphenyl ethers. After using blends of B2 with 10% and 20% water-containing butanol, the POP emission factors were decreased by amounts in the range of 22.6%-42.3% and 38.0%-65.5% on a mass basis, as well as 18.7%-78.1% and 51.0%-84.9% on a toxicity basis. The addition of water-containing butanol introduced a lower content of aromatic compounds and most importantly, lead to more complete combustion, thus resulting in a great reduction in the POP emissions. Not only did the self-provided oxygen of butanol promote complete oxidation but also the water content in butanol diesel blends could cause a microexplosion mechanism, which provided a better turbulence and well-mixed environment for complete combustion.

  11. Reducing emissions of persistent organic pollutants from a diesel engine by fueling with water-containing butanol diesel blends.

    PubMed

    Chang, Yu-Cheng; Lee, Wen-Jhy; Yang, Hsi-Hsien; Wang, Lin-Chi; Lu, Jau-Huai; Tsai, Ying I; Cheng, Man-Ting; Young, Li-Hao; Chiang, Chia-Jui

    2014-05-20

    The manufacture of water-containing butanol diesel blends requires no excess dehydration and surfactant addition. Therefore, compared with the manufacture of conventional bio-alcohols, the energy consumption for the manufacture of water-containing butanol diesel blends is reduced, and the costs are lowered. In this study, we verified that using water-containing butanol diesel blends not only solves the tradeoff problem between nitrogen oxides (NOx) and particulate matter emissions from diesel engines, but it also reduces the emissions of persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlorinated biphenyls, polychlorinated diphenyl ethers, polybrominated dibenzo-p-dioxins and dibenzofurans, polybrominated biphenyls and polybrominated diphenyl ethers. After using blends of B2 with 10% and 20% water-containing butanol, the POP emission factors were decreased by amounts in the range of 22.6%-42.3% and 38.0%-65.5% on a mass basis, as well as 18.7%-78.1% and 51.0%-84.9% on a toxicity basis. The addition of water-containing butanol introduced a lower content of aromatic compounds and most importantly, lead to more complete combustion, thus resulting in a great reduction in the POP emissions. Not only did the self-provided oxygen of butanol promote complete oxidation but also the water content in butanol diesel blends could cause a microexplosion mechanism, which provided a better turbulence and well-mixed environment for complete combustion. PMID:24738886

  12. Current status of persistent organic pesticides residues in air, water, and soil, and their possible effect on neighboring countries: a comprehensive review of India.

    PubMed

    Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Syed, Jabir Hussain; Cheng, Zhineng; Li, Jun; Zhang, Gan; Jones, Kevin C

    2015-04-01

    Though the use of pesticides has offered significant economic benefits by enhancing the production and yield of food and fibers and the prevention of vector-borne diseases, evidence suggests that their use has adversely affected the health of human populations and the environment. Pesticides have been widely distributed and their traces can be detected in all areas of the environment (air, water and soil). Despite the ban of DDT and HCH in India, they are still in use, both in domestic and agricultural settings. In this comprehensive review, we discuss the production and consumption of persistent organic pesticides, their maximum residual limit (MRL) and the presence of persistent organic pesticides in multicomponent environmental samples (air, water and soil) from India. In order to highlight the global distribution of persistent organic pesticides and their impact on neighboring countries and regions, the role of persistent organic pesticides in Indian region is reviewed. Based on a review of research papers and modeling simulations, it can be concluded that India is one of the major contributors of global persistent organic pesticide distribution. This review also considers the health impacts of persistent organic pesticides, the regulatory measures for persistent organic pesticides, and the status of India's commitment towards the elimination of persistent organic pesticides.

  13. How long can culturable bacteria and total DNA persist in environmental waters? The role of sunlight and solid particles.

    PubMed

    Gutiérrez-Cacciabue, Dolores; Cid, Alicia G; Rajal, Verónica B

    2016-01-01

    In this work, sunlight inactivation of two indicator bacteria in freshwater, with and without solid particles, was studied and the persistence of culturable cells and total DNA was compared. Environmental water was used to prepare two matrices, with and without solid particles, which were spiked with Escherichia coli and Enterococcus faecalis. These matrices were used to prepare microcosm bags that were placed in two containers: one exposed to sunlight and the other in the dark. During one month, samples were removed from each container and detection was done by membrane filter technique and real-time PCR. Kinetic parameters were calculated to assess sunlight effect. Indicator bacteria without solid particles exposed to sunlight suffered an immediate decay (<4h) compared with the ones which were shielded from them. In addition, the survival of both bacteria with solid particles varied depending on the situation analyzed (T99 from 3 up to 60days), being always culturable E. coli more persistent than E. faecalis. On the other side, E. faecalis DNA persisted much longer than culturable cells (T99>40h in the dark with particles). In this case active cells were more prone to sunlight than total DNA and the protective effect of solid particles was also observed. Results highlight that the effects caused by the parameters which describe the behavior of culturable microorganisms and total DNA in water are different and must be included in simulation models but without forgetting that these parameters will also depend on bacterial properties, sensitizers, composition, type, and uses of the aquatic environment under assessment.

  14. Uranium plume persistence impacted by hydrologic and geochemical heterogeneity in the groundwater and river water interaction zone of Hanford site

    NASA Astrophysics Data System (ADS)

    Chen, X.; Zachara, J. M.; Vermeul, V. R.; Freshley, M.; Hammond, G. E.

    2015-12-01

    The behavior of a persistent uranium plume in an extended groundwater- river water (GW-SW) interaction zone at the DOE Hanford site is dominantly controlled by river stage fluctuations in the adjacent Columbia River. The plume behavior is further complicated by substantial heterogeneity in physical and geochemical properties of the host aquifer sediments. Multi-scale field and laboratory experiments and reactive transport modeling were integrated to understand the complex plume behavior influenced by highly variable hydrologic and geochemical conditions in time and space. In this presentation we (1) describe multiple data sets from field-scale uranium adsorption and desorption experiments performed at our experimental well-field, (2) develop a reactive transport model that incorporates hydrologic and geochemical heterogeneities characterized from multi-scale and multi-type datasets and a surface complexation reaction network based on laboratory studies, and (3) compare the modeling and observation results to provide insights on how to refine the conceptual model and reduce prediction uncertainties. The experimental results revealed significant spatial variability in uranium adsorption/desorption behavior, while modeling demonstrated that ambient hydrologic and geochemical conditions and heterogeneities in sediment physical and chemical properties both contributed to complex plume behavior and its persistence. Our analysis provides important insights into the characterization, understanding, modeling, and remediation of groundwater contaminant plumes influenced by surface water and groundwater interactions.

  15. Persistence of pharmaceuticals and other organic compounds in chlorinated drinking water as a function of time

    USGS Publications Warehouse

    Gibs, J.; Stackelberg, P.E.; Furlong, E.T.; Meyer, M.; Zaugg, S.D.; Lippincott, R.L.

    2007-01-01

    Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2??mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10??days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24??h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution. ?? 2006 Elsevier B.V. All rights reserved.

  16. THE PERSISTENCE OF MYCOBACTERIUM AVIUM IN A DRINKING WATER SYSTEM AFTER THE ADDITION OF FILTRATION

    EPA Science Inventory

    Drinking water is increasingly recognized as a major source of pathogenic nontuberculous mycobacteria (NTM) associated with human infection. Our goal was to determine if the prevalence of NTM would decrease after the addition of filtration treatment to an unfiltered surface water...

  17. Persistence of Multi-Drug Resistance Plasmids in Sterile Water under Very Low Concentrations of Tetracycline

    PubMed Central

    Bien, Thi Lan Thanh; Sato-Takabe, Yuki; Ogo, Mitsuko; Usui, Masaru; Suzuki, Satoru

    2015-01-01

    The persistence of the multi-drug resistance plasmids pAQU1 and IncFIB was examined in bacterial populations under very low selective pressure. We herein demonstrated that these plasmids stably remained not only in the original host, but also in a transconjugant, even after being in a non-culturable state. In seawater microcosms containing Photobacterium damselae 04Ya311 possessing pAQU1, no significant loss of pAQU1 was observed during a 30-d starvation period. The copy numbers of pAQU1 and IncFIB in E. coli were constant. The results of the present study suggest that these plasmids have the ability to remain among various bacteria under oligotrophic conditions with low antibiotic selection pressure. PMID:26639579

  18. Influence of parasitism in dogs on their serum levels of persistent organochlorine compounds and polycyclic aromatic hydrocarbons.

    PubMed

    Henríquez-Hernández, Luis A; Carretón, Elena; Camacho, María; Montoya-Alonso, José Alberto; Boada, Luis D; Valerón, Pilar F; Cordón, Yaiza Falcón; Almeida-González, Maira; Zumbado, Manuel; Luzardo, Octavio P

    2016-08-15

    Persistent organochlorine pollutants (POPs) are toxic chemicals, which accumulate in humans and animals, as only few species have the capability of eliminating them. However, some authors have pointed to the possibility that certain species of invertebrates (i.e. nematodes) could metabolize this type of compounds. As certain species of nematodes act as parasites of vertebrates, this research was designed to explore the influence of some of the most common parasites of the dogs in their serum levels of 56 common POPs. The study included three groups of dogs (n=64), which were prospectively recruited in the island of Gran Canaria (Canary Islands, Spain): a) control animals, non-parasitized (serologically tested negative, n=24); b) dogs tested positive for intestinal parasites and negative for other parasites (n=24); and c) dogs tested positive for heartworm disease (Dirofilaria immitis) and negative for other parasites (n=16). The presence of Dirofilaria immitis was strongly associated with lower serum levels of a wide range of pollutant in their hosts (PCB congeners 28, 52, 118, 138, 153, and 180; hexachlorobenzene, lindane, aldrin, dieldrin, anthracene and pyrene). We also found an inverse association between the hosts' serum levels of PCBs and intestinal parasites. We did not find any association with DDT or its metabolites, but this might be explained by the recently suggested ability of dogs for the efficient metabolization of these compounds. According to the results of this study certain forms of parasitism would reduce the bioavailability of the major classes of POPs in dogs. However, further studies are needed to elucidate whether this phenomenon is due to a competence between parasites and hosts or could respond to a possible capability of parasitic nematodes for the metabolization of these POPs. PMID:27096633

  19. A siphon gage for monitoring surface-water levels

    USGS Publications Warehouse

    McCobb, T.D.; LeBlanc, D.R.; Socolow, R.S.

    1999-01-01

    A device that uses a siphon tube to establish a hydraulic connection between the bottom of an onshore standpipe and a point at the bottom of a water body was designed and tested for monitoring surface-water levels. Water is added to the standpipe to a level sufficient to drive a complete slug of water through the siphoning tube and to flush all air out of the system. The water levels in the standpipe and the water body equilibrate and provide a measurable static water surface in the standpipe. The siphon gage was designed to allow quick and accurate year-round measurements with minimal maintenance. Currently available devices for monitoring surface-water levels commonly involve time-consuming and costly installation and surveying, and the movement of reference points and the presence of ice cover in cold regions cause discontinuity and inaccuracy in the data collected. Installation and field testing of a siphon gage using 0.75-in-diameter polyethylene tubing at Ashumet Pond in Falmouth, Massachusetts, demonstrated that the siphon gage can provide long-term data with a field effort and accuracy equivalent to measurement of ground-water levels at an observation well.A device that uses a siphon tube to establish a hydraulic connection between the bottom of an onshore standpipe and a point at the bottom of a water body was designed and tested for monitoring surface-water levels. Water is added to the standpipe to a level sufficient to drive a complete slug of water through the siphoning tube and to flush all air out of the system. The water levels in the standpipe and the water body equilibrate and provide a measurable static water surface in the standpipe. The siphon gage was designed to allow quick and accurate year-round measurements with minimal maintenance. Currently available devices for monitoring surface-water levels commonly involve time-consuming and costly installation and surveying, and the movement of reference points and the presence of ice cover in cold

  20. Predation and transport of persistent pathogens in GAC and slow sand filters: a threat to drinking water safety?

    PubMed

    Bichai, Françoise; Dullemont, Yolanda; Hijnen, Wim; Barbeau, Benoit

    2014-11-01

    Zooplankton has been shown to transport internalized pathogens throughout engineered drinking water systems. In this study, experimental measurements from GAC and SSF filtration tests using high influent concentrations of Cryptosporidium (1.3 × 10(6) and 3.3 × 10(4) oocysts L(-1)) and Giardia (4.8 × 10(4) cysts L(-1)) are presented and compared. A predation and transport conceptual model was developed to extrapolate these results to environmental conditions of typical (oo)cyst concentrations in surface water in order to predict concentrations of internalized (oo)cysts in filtered water. Pilot test results were used to estimate transport and survival ratios of internalized (oo)cysts following predation by rotifers in the filter beds. Preliminary indications of lower transport and survival ratios in SSF were found as compared with GAC filters. A probability of infection due to internalized (oo)cysts in filtered water was calculated under likeliest environmental conditions and under a worst-case scenario. Estimated risks under the likeliest environmental scenario were found to fall below the tolerable risk target of 10(-4) infections per person per year. A discussion is presented on the health significance of persistent pathogens that are internalized by zooplankton during granular filtration processes and released into treated water.

  1. Are persistent early onset child conduct problems predicted by the trajectories and initial levels of discipline practices?

    PubMed

    Lorber, Michael F; Slep, Amy M Smith

    2015-08-01

    In the present investigation we focused on 2 broad sets of questions: Do parental overreactivity, laxness, and corporal punishment show evidence of normative change in early to middle childhood? Are persistently elevated child conduct problems (CPs) associated with deviations from normative changes in, as well as high initial levels of, discipline practices? Four hundred fifty-three couples with 3- to 7-year-old children were recruited via random digit dialing and studied at 3 annual assessments. Parents completed questionnaire measures of all study constructs. Normative declines were found in maternal corporal punishment and laxness. Maternal overreactivity showed a normative increase. For fathers, only corporal punishment showed evidence of a normative decline. The declines in mothers' corporal punishment and laxness, and in fathers' corporal punishment, exhibited little variability. In contrast, the trajectories of maternal overreactivity were significantly variable. High-increasing CPs were more common than low-stable CPs in families with greater increases in maternal overreactivity. High-increasing CPs were also more common in families with greater initial maternal overreactivity and corporal punishment. Yet in no case did discipline practices significantly distinguish children on high-increasing versus high-decreasing CPs trajectories. In tests of alternative models, child effects were found for all parenting variables, suggesting reciprocal causation. The findings are discussed relative to etiological models of CPs and implications for preventive intervention.

  2. Persistent organic pollutant levels in eggs of leatherback turtles (Dermochelys coriacea) point to a decrease in hatching success.

    PubMed

    De Andrés, Eva; Gómara, Belén; González-Paredes, Daniel; Ruiz-Martín, José; Marco, Adolfo

    2016-03-01

    Sea turtles are susceptible to environmental pollution, since many harmful effects have been reported for different chemicals over the last two decades. In this context, persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are of particular concern due to their endocrine-disrupting nature. The aims of this study were to provide additional baseline data on PCB and PBDE concentrations in eggs of Dermochelys coriacea; and to investigate whether any of the congeners could compromise reproductive success in this species. A total of 18 nests from different females were studied during the nesting season of 2008 at Reserva Pacuare Beach, in the Caribbean side of Costa Rica. Reproductive parameters (viability, fertility and hatching rates) were calculated for all nests and hatchling morphometrics were successfully measured in 8 of them. Two to three fresh eggs per nest were taken for contaminant study. Different congeners of POPs were purified and identified using gas chromatography (GC) coupled to an ion trap detector (GC-ITD MS/MS), as described below. Mean ± SD concentrations were calculated for POP congeners within each nest and clustering was also evaluated. Correlations were performed searching for potential relationships with reproductive parameters. POP levels were similar to those reported in French-Guiana populations and slightly lower than those associated to Florida populations. Sum of PBDEs showed a negative correlation to the hatching success, suggesting potential harmful effects of these contaminants on the reproduction of leatherbacks. PMID:26735737

  3. Persistent organic pollutant levels in eggs of leatherback turtles (Dermochelys coriacea) point to a decrease in hatching success.

    PubMed

    De Andrés, Eva; Gómara, Belén; González-Paredes, Daniel; Ruiz-Martín, José; Marco, Adolfo

    2016-03-01

    Sea turtles are susceptible to environmental pollution, since many harmful effects have been reported for different chemicals over the last two decades. In this context, persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are of particular concern due to their endocrine-disrupting nature. The aims of this study were to provide additional baseline data on PCB and PBDE concentrations in eggs of Dermochelys coriacea; and to investigate whether any of the congeners could compromise reproductive success in this species. A total of 18 nests from different females were studied during the nesting season of 2008 at Reserva Pacuare Beach, in the Caribbean side of Costa Rica. Reproductive parameters (viability, fertility and hatching rates) were calculated for all nests and hatchling morphometrics were successfully measured in 8 of them. Two to three fresh eggs per nest were taken for contaminant study. Different congeners of POPs were purified and identified using gas chromatography (GC) coupled to an ion trap detector (GC-ITD MS/MS), as described below. Mean ± SD concentrations were calculated for POP congeners within each nest and clustering was also evaluated. Correlations were performed searching for potential relationships with reproductive parameters. POP levels were similar to those reported in French-Guiana populations and slightly lower than those associated to Florida populations. Sum of PBDEs showed a negative correlation to the hatching success, suggesting potential harmful effects of these contaminants on the reproduction of leatherbacks.

  4. High Levels of Persistent Problem Drinking in Women at High Risk for HIV in Kampala, Uganda: A Prospective Cohort Study

    PubMed Central

    Weiss, Helen A.; Vandepitte, Judith; Bukenya, Justine N.; Mayanja, Yunia; Nakubulwa, Susan; Kamali, Anatoli; Seeley, Janet; Grosskurth, Heiner

    2016-01-01

    The aim of this study was to describe the epidemiology of problem drinking in a cohort of women at high-risk of HIV in Kampala, Uganda. Overall, 1027 women at high risk of HIV infection were followed from 2008 to 2013. The CAGE and AUDIT questionnaires were used to identify problem drinkers in the cohort. Interviewer-administered questionnaires were used to ascertain socio-demographic and behavioural factors. Blood and genital samples were tested for HIV and other sexually transmitted infections. At enrollment, most women (71%) reported using alcohol at least weekly and about a third reported having drunk alcohol daily for at least 2 weeks during the past 3 months. Over half (56%) were problem drinkers by CAGE at enrollment, and this was independently associated with vulnerability (being divorced/separated/widowed, less education, recruiting clients at bars/clubs, and forced sex at first sexual experience). Factors associated with problem drinking during follow-up included younger age, meeting clients in bars/clubs, number of clients, using drugs and HSV-2 infection. HIV prevalence was associated with drinking at enrollment, but not during follow-up. This longitudinal study found high levels of persistent problem drinking. Further research is needed to adapt and implement alcohol-focused interventions in vulnerable key populations in sub-Saharan Africa. PMID:26805868

  5. Persistence of low-pathogenic H5N7 and H7N1 avian influenza subtypes in filtered natural waters.

    PubMed

    Nielsen, Anne Ahlmann; Jensen, Trine Hammer; Stockmarr, Anders; Jørgensen, Poul Henrik

    2013-10-25

    Wild aquatic birds are the natural reservoir of avian influenza virus (AIV), and the virus is transmitted among birds through a fecal-oral route. Infected birds excrete significant amounts of AIV into the environment, and thereby sustain the circulation of AIV in the bird populations. Improved knowledge on the influence of environmental factors on the persistence of AIV in natural habitats would be valuable for risk assessments. The presented work investigated the persistence of two low-pathogenic AIV subtypes in natural water samples. The study included two AIVs formerly isolated from wild ducks, which were suspended in filtered natural fresh, brackish or sea water with salinity of 0, 8000 and 20,000 parts per million (ppm), respectively. Also sterilized brackish and sea waters were included in order to examine the influence of microbial flora on virus persistence. All water samples were incubated at temperatures representative for seasonal variation of ambient temperatures in Northern Europe (4, 17 and 25 °C). The results showed a clear correlation between persistence of viral infectivity and temperature, salinity and presence of microbial flora. While independent of virus subtype, the persistence of infectivity was negatively affected by increased temperature, salinity as well as presence of natural microbial flora. The study provides insight on impact of essential physical, chemical and biological parameters on persistence of AIV in aquatic environments. Studies determining the importance of additional environmental parameters and the detailed mechanisms of microbial inactivation of AIV should be encouraged.

  6. Persistence of legacy soil P and elevated background water P concentrations in Water Conservation Area 2A, a northern Everglades wetland

    NASA Astrophysics Data System (ADS)

    Juston, John M.; Kadlec, Robert H.; DeBusk, William F.; Jerauld, Mike J.; DeBusk, Thomas A.

    2015-12-01

    Upstream source control and Stormwater Treatment Areas (STAs) have reduced phosphorus (P) loads to Water Conservation Area 2A (WCA-2A), a northern Everglades wetland, by three quarters since year 2000. Nevertheless, large storages of P remain in enriched peat soils and it is unclear how legacy stores will impact spatial and temporal scales of recovery. We remeasured soil P enrichment along a well-studied eutrophication gradient in WCA-2A and applied a profile modeling approach with uncertainty analysis to assess changes in longitudinal soil P gradients 13 years after load reductions. We then analyzed existing internal water P data, using a novel data screening approach, for evidence of lowest possible water P concentrations independent from inflows. We interpret such water P limits as evidence of the strength of internal loading at a location. Results indicate that soil P enrichment persists in the ˜7.5 km long "impacted" zone, with no significant evidence of net advancement or recession, while a large pool of labile P in the flocculent layer consolidated and diminished. There is indeed evidence, both spatial and temporal, that this extensive zone of enriched soil P continues to elevate lowest achievable water P concentrations. The corresponding gradient of elevated water P limits is both receding and diminishing since load reductions, thus providing further evidence toward recovery. However, results also suggest that these "transitory P limits" due to internal loading are likely to persist for decades above water quality targets. These results advance our understanding of recovery in impacted wetlands and are relevant to Everglades restoration.

  7. Specific conductance, water temperature, and water level data, San Francisco Bay, California, water year 1998

    USGS Publications Warehouse

    Buchanan, Paul A.

    1999-01-01

    Specific conductance and water temperature data are continuously recorded at four sites in San Francisco Bay, California: San Pablo Strait at Point San Pablo, Central San Francisco Bay at Presidio Military Reservation, Pier 24 at Bay Bridge, and South San Francisco Bay at San Mateo Bridge near Foster City (Figure 1). Water level data are recorded only at San Pablo Strait at Point San Pablo. These data were recorded by the Department of Water Resources (DWR) before 1988, by the US Geological Survey (USGS) National Research Program from 1988 to 1989, and by the USGS-DWR cooperative program since 1990. This article presents time-series plots of data from the four sites in San Francisco Bay during water year 1998 (1 October 1997 through 30 September 1998).

  8. Potential of pulsed corona discharges generated in water for the degradation of persistent pharmaceutical residues.

    PubMed

    Banaschik, Robert; Lukes, Petr; Jablonowski, Helena; Hammer, Malte U; Weltmann, Klaus-Dieter; Kolb, Juergen F

    2015-11-01

    Anthropogenic pollutants and in particular pharmaceutical residues are a potential risk for potable water where they are found in increasing concentrations. Different environmental effects could already be linked to the presence of pharmaceuticals in surface waters even for low concentrations. Many pharmaceuticals withstand conventional water treatment technologies. Consequently, there is a need for new water purification techniques. Advanced oxidation processes (AOP), and especially plasmas with their ability to create reactive species directly in water, may offer a promising solution. We developed a plasma reactor with a coaxial geometry to generate large volume corona discharges directly in water and investigated the degradation of seven recalcitrant pharmaceuticals (carbamazepine, diatrizoate, diazepam, diclofenac, ibuprofen, 17α-ethinylestradiol, trimethoprim). For most substances we observed decomposition rates from 45% to 99% for treatment times of 15-66 min. Especially ethinylestradiol and diclofenac were readily decomposed. As an inherent advantage of the method, we found no acidification and only an insignificant increase in nitrate/nitrite concentrations below legal limits for the treatment. Studies on the basic plasma chemical processes for the model system of phenol showed that the degradation is primarily caused by hydroxyl radicals. PMID:26218466

  9. Potential of pulsed corona discharges generated in water for the degradation of persistent pharmaceutical residues.

    PubMed

    Banaschik, Robert; Lukes, Petr; Jablonowski, Helena; Hammer, Malte U; Weltmann, Klaus-Dieter; Kolb, Juergen F

    2015-11-01

    Anthropogenic pollutants and in particular pharmaceutical residues are a potential risk for potable water where they are found in increasing concentrations. Different environmental effects could already be linked to the presence of pharmaceuticals in surface waters even for low concentrations. Many pharmaceuticals withstand conventional water treatment technologies. Consequently, there is a need for new water purification techniques. Advanced oxidation processes (AOP), and especially plasmas with their ability to create reactive species directly in water, may offer a promising solution. We developed a plasma reactor with a coaxial geometry to generate large volume corona discharges directly in water and investigated the degradation of seven recalcitrant pharmaceuticals (carbamazepine, diatrizoate, diazepam, diclofenac, ibuprofen, 17α-ethinylestradiol, trimethoprim). For most substances we observed decomposition rates from 45% to 99% for treatment times of 15-66 min. Especially ethinylestradiol and diclofenac were readily decomposed. As an inherent advantage of the method, we found no acidification and only an insignificant increase in nitrate/nitrite concentrations below legal limits for the treatment. Studies on the basic plasma chemical processes for the model system of phenol showed that the degradation is primarily caused by hydroxyl radicals.

  10. Emergence and fate of cyclic volatile polydimethylsiloxanes (D4, D5) in municipal waste streams: release mechanisms, partitioning and persistence in air, water, soil and sediments.

    PubMed

    Surita, Sharon C; Tansel, Berrin

    2014-01-15

    Siloxane use in consumer products (i.e., fabrics, paper, concrete, wood, adhesive surfaces) has significantly increased in recent years due to their excellent water repelling and antimicrobial characteristics. The objectives of this study were to evaluate the release mechanisms of two siloxane compounds, octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5), which have been detected both at landfills and wastewater treatment plants, estimate persistence times in different media, and project release quantities over time in relation to their increasing use. Analyses were conducted based on fate and transport mechanisms after siloxanes enter waste streams. Due to their high volatility, the majority of D4 and D5 end up in the biogas during decomposition. D5 is about ten times more likely to partition into the solid phase (i.e., soil, biosolids). D5 concentrations in the wastewater influent and biogas are about 16 times and 18 times higher respectively, in comparison to the detected levels of D4.

  11. Emergence and fate of cyclic volatile polydimethylsiloxanes (D4, D5) in municipal waste streams: release mechanisms, partitioning and persistence in air, water, soil and sediments.

    PubMed

    Surita, Sharon C; Tansel, Berrin

    2014-01-15

    Siloxane use in consumer products (i.e., fabrics, paper, concrete, wood, adhesive surfaces) has significantly increased in recent years due to their excellent water repelling and antimicrobial characteristics. The objectives of this study were to evaluate the release mechanisms of two siloxane compounds, octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5), which have been detected both at landfills and wastewater treatment plants, estimate persistence times in different media, and project release quantities over time in relation to their increasing use. Analyses were conducted based on fate and transport mechanisms after siloxanes enter waste streams. Due to their high volatility, the majority of D4 and D5 end up in the biogas during decomposition. D5 is about ten times more likely to partition into the solid phase (i.e., soil, biosolids). D5 concentrations in the wastewater influent and biogas are about 16 times and 18 times higher respectively, in comparison to the detected levels of D4. PMID:24012894

  12. Forty-seven days of decay does not change persistent organic pollutant levels in loggerhead sea turtle eggs.

    PubMed

    Keller, Jennifer M

    2013-04-01

    Reptile and bird eggs are priority samples for specimen banking programs that assess spatial and temporal trends of environmental contaminants. From endangered species, such as sea turtles, nonlethal sampling is required (e.g., unhatched eggs collected postemergence). Previous contaminant monitoring studies have used unhatched sea turtle eggs, but no study has tested whether their concentrations represent levels found in fresh eggs (e.g., eggs collected within 24 h of oviposition). The author analyzed three fresh eggs from different nest depths and up to three unhatched eggs from 10 loggerhead sea turtle (Caretta caretta) nests in South Carolina, USA, for a suite of persistent organic pollutants (POPs). Lipid-normalized POP concentrations were not significantly different (p > 0.05) between fresh and unhatched eggs or among different depths from the same nest. The POP concentrations in loggerhead eggs from South Carolina were higher than previously measured concentrations in eggs from Florida and slightly lower than concentrations in eggs from North Carolina. This pattern agrees with previously observed trends of increasing POP concentrations in loggerhead turtles inhabiting northern latitudes along the U.S. East Coast. Contaminant profiles are discussed, including a higher chlorinated pattern of polychlorinated biphenyls possibly associated with a Superfund site in nearby Brunswick, Georgia, USA, and unusual polybrominated diphenylether patterns seen in this and previous sea turtle studies. Concentrations correlated with one of eight measurements of reproductive success; levels were negatively correlated with egg mass (p < 0.05), which may have implications for hatchling fitness. The present study suggests that unhatched eggs can be used for POP-monitoring projects.

  13. Forty-seven days of decay does not change persistent organic pollutant levels in loggerhead sea turtle eggs.

    PubMed

    Keller, Jennifer M

    2013-04-01

    Reptile and bird eggs are priority samples for specimen banking programs that assess spatial and temporal trends of environmental contaminants. From endangered species, such as sea turtles, nonlethal sampling is required (e.g., unhatched eggs collected postemergence). Previous contaminant monitoring studies have used unhatched sea turtle eggs, but no study has tested whether their concentrations represent levels found in fresh eggs (e.g., eggs collected within 24 h of oviposition). The author analyzed three fresh eggs from different nest depths and up to three unhatched eggs from 10 loggerhead sea turtle (Caretta caretta) nests in South Carolina, USA, for a suite of persistent organic pollutants (POPs). Lipid-normalized POP concentrations were not significantly different (p > 0.05) between fresh and unhatched eggs or among different depths from the same nest. The POP concentrations in loggerhead eggs from South Carolina were higher than previously measured concentrations in eggs from Florida and slightly lower than concentrations in eggs from North Carolina. This pattern agrees with previously observed trends of increasing POP concentrations in loggerhead turtles inhabiting northern latitudes along the U.S. East Coast. Contaminant profiles are discussed, including a higher chlorinated pattern of polychlorinated biphenyls possibly associated with a Superfund site in nearby Brunswick, Georgia, USA, and unusual polybrominated diphenylether patterns seen in this and previous sea turtle studies. Concentrations correlated with one of eight measurements of reproductive success; levels were negatively correlated with egg mass (p < 0.05), which may have implications for hatchling fitness. The present study suggests that unhatched eggs can be used for POP-monitoring projects. PMID:23418059

  14. Proximity to encroaching coconut palm limits native forest water use and persistence on a Pacific atoll

    USGS Publications Warehouse

    Krauss, Ken W.; Duberstein, Jamie A.; Cormier, Nicole; Young, Hillary S.; Hathaway, Stacie A.

    2015-01-01

    Competition for fresh water between native and introduced plants is one important challenge facing native forests as rainfall variability increases. Competition can be especially acute for vegetation on Pacific atolls, which depend upon consistent rainfall to replenish shallow groundwater stores. Patterns of sap flow, water use, and diameter growth of Pisonia grandis trees were investigated on Sand Islet, Palmyra Atoll, Line Islands, during a period of low rainfall. Sap flow in the outer sapwood was reduced by 53% for P. grandis trees growing within coconut palm (Cocos nucifera) stands (n = 9) versus away from coconut palm (n = 9). This suggested that water uptake was being limited by coconut palm. Radial patterns of sap flow into the sapwood of P. grandis also differed between stands with and without coconut palm, such that individual tree water use for P. grandis ranged from 14 to 67 L day−1, averaging 47·8 L day−1 without coconut palm and 23·6 L day−1 with coconut palm. Diameter growth of P. grandis was measured from nine islets. In contrast to sap flow, competition with coconut palm increased diameter growth by 89%, equating to an individual tree basal area increment of 5·4 versus 10·3 mm2 day−1. Greater diameter growth countered by lower rates of water use by P. grandis trees growing in competition with coconut palm suggests that stem swell may be associated with water storage when positioned in the understory of coconut palm, and may facilitate survival when water becomes limiting until too much shading overwhelms P. grandis. 

  15. Water level and strain changes preceding and following the August 4, 1985 Kettleman Hills, California, earthquake

    USGS Publications Warehouse

    Roeloffs, E.; Quilty, E.

    1997-01-01

    Two of the four wells monitored near Parkfield, California, during 1985 showed water level rises beginning three days before the M4 6.1 Kettleman Hills earthquake. In one of these wells, the 3.0 cm rise was nearly unique in five years of water level data. However, in the other well, which showed a 3.8 cm rise, many other changes of comparable size have been observed. Both wells that did not display pre-earthquake rises tap partially confined aquifers that cannot sustain pressure changes due to tectonic strain having periods longer than several days. We evaluate the effect of partial aquifer confinement on the ability of these four wells to display water level changes in response to aquifer strain. Although the vertical hydraulic diffusivities cannot be determined uniquely, we can find a value of diffusivity for each site that is consistent with the site's tidal and barometric responses as well as with the rate of partial recovery of the coseismic water level drops. Furthermore, the diffusivity for one well is high enough to explain why the preseismic rise could not have been detected there. For the fourth well, the diffusivity is high enough to have reduced the size of the preseismic signal as much as 50%, although it should still have been detectable. Imperfect confinement cannot explain the persistent water level changes in the two partially confined aquifers, but it does show that they were not due to volume strain. The pre-earthquake water level rises may have been precursors to the Kettleman Hills earthquake. If so, they probably were not caused by accelerating slip over the part of the fault plane that ruptured in that earthquake because they are of opposite sign to the observed coseismic water level drops.

  16. Persistent organic pollutant levels in human visceral and subcutaneous adipose tissue in obese individuals—Depot differences and dysmetabolism implications

    SciTech Connect

    Pestana, Diogo; Faria, Gil; Sá, Carla; Fernandes, Virgínia C.; Teixeira, Diana; Norberto, Sónia; Faria, Ana; and others

    2014-08-15

    Background: The role of persistent organic pollutants (POPs) with endocrine disrupting activity in the aetiology of obesity and other metabolic dysfunctions has been recently highlighted. Adipose tissue (AT) is a common site of POPs accumulation where they can induce adverse effects on human health. Objectives: To evaluate the presence of POPs in human visceral (vAT) and subcutaneous (scAT) adipose tissue in a sample of Portuguese obese patients that underwent bariatric surgery, and assess their putative association with metabolic disruption preoperatively, as well as with subsequent body mass index (BMI) reduction. Methods: AT samples (n=189) from obese patients (BMI ≥35) were collected and the levels of 13 POPs were determined by gas chromatography with electron-capture detection (GC-ECD). Anthropometric and biochemical data were collected at the time of surgery. BMI variation was evaluated after 12 months and adipocyte size was measured in AT samples. Results: Our data confirm that POPs are pervasive in this obese population (96.3% of detection on both tissues), their abundance increasing with age (R{sub S}=0.310, p<0.01) and duration of obesity (R{sub S}=0.170, p<0.05). We observed a difference in AT depot POPs storage capability, with higher levels of ΣPOPs in vAT (213.9±204.2 compared to 155.1±147.4 ng/g of fat, p<0.001), extremely relevant when evaluating their metabolic impact. Furthermore, there was a positive correlation between POP levels and the presence of metabolic syndrome components, namely dysglycaemia and hypertension, and more importantly with cardiovascular risk (R{sub S}=0.277, p<0.01), with relevance for vAT (R{sub S}=0.315, p<0.01). Finally, we observed an interesting relation of higher POP levels with lower weight loss in older patients. Conclusion: Our sample of obese subjects allowed us to highlight the importance of POPs stored in AT on the development of metabolic dysfunction in a context of obesity, shifting the focus to their

  17. Corals persisting in naturally turbid waters adjacent to a pristine catchment in Solomon Islands.

    PubMed

    Albert, Simon; Fisher, Paul L; Gibbes, Badin; Grinham, Alistair

    2015-05-15

    Few water quality measurements exist from pristine environments, with fewer reported studies of coastal water quality from Solomon Islands. Water quality benchmarks for the Solomons have relied on data from other geographic regions, often from quite different higher latitude developed nations, with large land masses. We present the first data of inshore turbidity and sedimentation rate for a pristine catchment on Isabel Island. Surveys recorded relatively high coral cover. The lowest cover was recorded at 22.7% (Jejevo) despite this site having a mean turbidity (continuous monitoring) of 32 NTU. However, a similar site (Jihro) was significantly less turbid (2.1 mean NTU) over the same period. This difference in turbidity is likely due to natural features of the Jihro River promoting sedimentation before reaching coastal sites. We provide an important baseline for Solomon Island inshore systems, whilst demonstrating the importance of continuous monitoring to capture episodic high turbidity events. PMID:25752531

  18. Ground-water level data for North Carolina, 1987

    USGS Publications Warehouse

    Coble, Ronald W.; Strickland, A.G.; Bailey, M. Carl

    1989-01-01

    Continuous and periodic measurements in 54 key wells and water-level measurements emplaced in Coastal Plain aquifers across North Carolina in 193 supplemental wells are presented in this report. Hydrographs of selected wells show changes in ground-water storage in the State. The water table in the shallow aquifers was higher throughout most of the State in 1987 than in 1986, indicating that rain had recharged these aquifers sufficiently to replenish the deficit in ground water storage that accumulated in the western and central parts of the State during 1986. Water levels in the heavily pumped Coastal Plain aquifers show a general downward trend for the year, indicating ground water is being withdrawn from aquifer storage. Record low water levels were measured in 4 of 13 wells in the Castle Hayne aquifer; the greatest decline measured during 1987 was 0.3 ft. Water levels in wells in the Peedee, Black Creek, upper Cape Fear, and lower Cape Fear aquifers generally show downward trends. Record low water levels were measured in 4 of 8 wells in the Peedee aquifer; the maximum decline measured during 1987 was 1.5 ft. All wells in the Black Creek, upper Cape Fear, and lower Cape Fear aquifers had record low water levels for 1987, with maximum measured declines in 1987 of 8.6, 3.1, and 3.1 ft., respectively. Record high water levels were measured in two wells, one each in the Castle Hayne and Peedee aquifers. Potentiometric surface maps show the effects of major centers of pumping for the Castle Hayne, Black Creek, and lower Cape Fear aquifers of the Coastal Plain.

  19. Sea snakes (Laticauda spp.) require fresh drinking water: implication for the distribution and persistence of populations.

    PubMed

    Lillywhite, Harvey B; Babonis, Leslie S; Sheehy, Coleman M; Tu, Ming-Chung

    2008-01-01

    Dehydration and procurement of water are key problems for vertebrates that have secondarily invaded marine environments. Sea snakes and other marine reptiles are thought to remain in water balance without consuming freshwater, owing to the ability of extrarenal salt glands to excrete excess salts obtained either from prey or from drinking seawater directly. Contrary to this long-standing dogma, we report that three species of sea snake actually dehydrate in marine environments. We investigated dehydration and drinking behaviors in three species of amphibious sea kraits (Laticauda spp.) representing a range of habits from semiterrestrial to very highly marine. Snakes that we dehydrated either in air or in seawater refused to drink seawater but drank freshwater or very dilute brackish water (10%-30% seawater) to remain in water balance. We further show that Laticauda spp. can dehydrate severely in the wild and are far more abundant at sites where there are sources of freshwater. A more global examination of all sea snakes demonstrates that species richness correlates positively with mean annual precipitation within the Indo-West Pacific tropical region. The dependence of Laticauda spp. on freshwater might explain the characteristically patchy distributions of these reptiles and is relevant to understanding patterns of extinctions and possible future responses to changes in precipitation related to global warming. In particular, metapopulation dynamics of the Laticauda group of sea snakes are expected to change in relation to projected reductions of tropical dry-season precipitation.

  20. Genes indicative of zoonotic and swine pathogens are persistent in stream water and sediment following a swine manure spill

    USGS Publications Warehouse

    Haack, Sheridan K.; Duris, Joseph W.; Kolpin, Dana W.; Fogarty, Lisa R.; Johnson, Heather E.; Gibson, Kristen E.; Focazio, Michael J.; Schwab, Kellogg J.; Hubbard, Laura E.; Foreman, William T.

    2015-01-01

    Manure spills to streams are relatively frequent, but no studies have characterized stream contamination with zoonotic and veterinary pathogens, or fecal chemicals, following a spill. We tested stream water and sediment over 25 days and downstream for 7.6 km for: fecal indicator bacteria (FIB); the fecal indicator chemicals cholesterol and coprostanol; 20 genes for zoonotic and swine-specific bacterial pathogens by presence/absence polymerase chain reaction (PCR) for viable cells; one swine-specific Escherichia coli toxin gene (STII) by quantitative PCR (qPCR); and nine human and animal viruses by qPCR, or reverse-transcriptase qPCR. Twelve days post-spill, and 4.2 km downstream, water concentrations of FIB, cholesterol, and coprostanol were 1-2 orders of magnitude greater than those detected before, or above, the spill, and genes indicating viable zoonotic or swine-infectious Escherichia coli, were detected in water or sediment. STII increased from undetectable before, or above the spill, to 105 copies/100 mL water 12 days post-spill. Thirteen of 14 water (8/9 sediment) samples had viable STII-carrying cells post-spill. Eighteen days post-spill porcine adenovirus and teschovirus were detected 5.6 km downstream. Sediment FIB concentrations (per gram wet weight) were greater than in water, and sediment was a continuous reservoir of genes and chemicals post-spill. Constituent concentrations were much lower, and detections less frequent, in a runoff event (200 days post-spill) following manure application, although the swine-associated STII and stx2e genes were detected. Manure spills are an underappreciated pathway for livestock-derived contaminants to enter streams, with persistent environmental outcomes, and the potential for human and veterinary health consequences.

  1. Persistent summertime water ice deposits in the northern plains of Mars: Observations from MRO CRISM

    NASA Astrophysics Data System (ADS)

    Seelos, K. D.; Seelos, F. P.; Murchie, S. L.; Titus, T. N.; CRISM Team

    2007-12-01

    Analysis of MRO CRISM multispectral mapping data obtained during the late northern summer season on Mars (Ls = 130-180 degrees) reveals small water ice deposits distributed throughout the northern plains at latitudes quite distant from the residual polar cap. These outliers range in size from a few hundreds of meters to several kilometers, and are generally associated with the northward facing slopes of crater rims or other elevated landforms. In a few instances the ice deposits are located on the leeward (southeast-facing) sides of larger craters, and may indicate the presence of wintertime CO2 frost formation from orographic lifting. The brighter frost sublimes more slowly than the surrounding CO2 ice, ultimately forming a late spring cold trap and inducing an accumulation of water ice. During the first 4 months of MRO primary science phase (PSP), CRISM was able to cover ~75% of the northern plains surface (at 75 degrees latitude) with 73 channel visible/near infrared (0.41 to 3.92 μm) multispectral data as part of its systematic global mapping campaign. These long, 10 km-wide strips of data are mosaicked together and resampled to 256 pix/deg (~231 m/pix) spatial resolution. CRISM's wavelength range is particularly well-suited to distinguishing between different types and grain sizes of CO2 and water ice, as well as iron- bearing minerals, sulfates, and phyllosilicates. False color composites of the multispectral data allow consistent mapping of the lowest latitudes of water ice occurrences and comparison to other global datasets. The average minimum latitude that water ice is observed during this time period is 75.5 degrees, with excursions of up to 10 degrees. Albedo appears to be a secondary control after local slope, and large scale topographic trends do not influence the locations of residual ice patches. Further comparison to Mars Odyssey GRS inferred subsurface water ice distribution may provide important clues regarding subsurface

  2. Removal of persistent organic pollutants from micro-polluted drinking water by triolein embedded absorbent.

    PubMed

    Liu, Huijuan; Ru, Jia; Qu, Jiuhui; Dai, Ruihua; Wang, Zijian; Hu, Chun

    2009-06-01

    A new biomimetic absorbent, cellulose acetate (CA) embedded with triolein (CA-triolein), was prepared and applied for the removal of persistent organic pollutants (POPs) from micro-polluted aqueous solution. The comparison of CA-triolein, CA and granular activated carbon (GAC) for dieldrin removal was investigated. Results showed that CA-triolein absorbent gave a lowest residual concentration after 24 h although GAC had high removal rate in the first 4 h adsorption. Then the removal efficiency of mixed POPs (e.g. aldrin, dieldrin, endrin and heptachlor epoxide), absorption isotherm, absorbent regeneration and initial column experiments of CA-triolein were studied in detail. The linear absorption isotherm and the independent absorption in binary isotherm indicated that the selected POPs are mainly absorbed onto CA-triolein absorbent by a partition mechanism. The absorption constant, K, was closely related to the hydrophobic property of the compound. Thermodynamic calculations showed that the absorption was spontaneous, with a high affinity and the absorption was an endothermic reaction. Rinsing with hexane the CA-triolein absorbent can be regenerated after absorption of POPs. No significant decrease in the dieldrin removal efficiency was observed even when the absorption-regeneration process was repeated for five times. The results of initial column experiments showed that the CA-triolein absorbent did not reach the breakthrough point at a breakthrough empty-bed volume (BV) of 3200 when the influent concentration was 1-1.5 microg/L and the empty-bed contact time (EBCT) was 20 min. PMID:19246190

  3. Temporal and spatial changes in persistent organic pollutants in Vietnamese coastal waters detected from plastic resin pellets.

    PubMed

    Le, Dung Quang; Takada, Hideshige; Yamashita, Rei; Mizukawa, Kaoruko; Hosoda, Junki; Tuyet, Dao Anh

    2016-08-15

    Plastic resin pellets collected at Minh Chau island and Ba Lat estuary between 2007 and 2014 in Vietnam were analyzed for dichloro-diphenyl-trichloroethanes (DDTs), polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs). The study was carried out as part of the International Pellet Watch program for monitoring the global distribution of persistent organic pollutants (POPs). Higher levels of DDTs compared to PCBs indicated agricultural inputs rather than industrial discharges in the region. Most POP concentrations on both beaches decreased over the period, with the exception of HCH isomers. Though the concentration of DDTs showed a drastic decline on both beaches between 2007/2008 and 2014, DDTs accounted for 60-80% of total DDTs, suggesting that there is still a fresh input of these chemicals in the region. This study strongly recommends further investigations to track temporal and spatial patterns of POP levels in the marine environment using plastic resin pellets. PMID:27262498

  4. Self-Determination and Goal Aspirations: African American and Latino Males' Perceptions of Their Persistence in Community College Basic and Transfer-Level Writing Courses

    ERIC Educational Resources Information Center

    Villarreal, María de Lourdes; García, Hugo A.

    2016-01-01

    This Grounded Theory study utilized Self-determination Theory to analyze the interview results of 18 community college African American and Latino males. The goal was to learn what helped participants to succeed and persist in developmental and transfer-level writing courses despite the obstacles that they faced. Three major themes emerged: (a)…

  5. Persistence of Fall 1988 ENGL 330/335 Students through Transfer Level English (1A) over Four Academic Years (Fall 1988-Spring 1992). Research Report #267.

    ERIC Educational Resources Information Center

    Kangas, Jon; Ma, Tony

    In fall 1992, a study was conducted at Evergreen Valley College (EVC) and San Jose City College (SJCC), in California, to measure the persistence rate of fall 1988 developmental English students (ENGL 330 at EVC; ENGL 335 at SJCC) through transfer level English (1A) over 4 academic years. Results of the study included the following: (1) of the 152…

  6. Correlation of Notch1/Hes1 Genes Expression Levels in Egyptian Paediatric Patients with Newly Diagnosed and Persistent Primary Immune(Idiopathic) Thrombocytopenic Purpura.

    PubMed

    Gawdat, Rania Mohsen; Hammam, Amira Ahmed; Ezzat, Dina Ahmed

    2016-09-01

    Notch signalling is involved in the development of several autoimmune diseases, one of such diseases is ITP. The aim of this study was to investigate and compare the expression levels of Notch1 receptor and its target Hes1 gene in Egyptian paediatric ITP patients. Real-time quantitative reverse transcriptase polymerase chain reaction was used to analyse the expression levels of Notch1 and Hes1 in 42 children with primary ITP (22 newly diagnosed and 20 persistent) cases. Twenty age and sex matched non-ITP controls were included. The expression levels of Notch1 were higher in newly diagnosed and persistent cases than controls with high statistical significant difference (P value < 0.001, P < 0.001) respectively, similarly as regards the expression levels of HES1 (P value < 0.001, P < 0.007) respectively. A significant positive correlation was found between Notch1 and Hes1 expression levels in newly diagnosed cases (r = 0.587, P value = 0.004). There was an association between levels of both genes in most of ITP patients but Hes1 was markedly elevated than Notch1 in few cases. High expression levels of Notch1/Hes1 indicated the important role of Notch signalling in both newly diagnosed and persistent ITP. High expression levels of Hes1 than Notch1 may shed light on its value as a therapeutic target for future research in ITP. PMID:27429531

  7. Occurrence and fate of the angiotensin II receptor antagonist transformation product valsartan acid in the water cycle--a comparative study with selected β-blockers and the persistent anthropogenic wastewater indicators carbamazepine and acesulfame.

    PubMed

    Nödler, Karsten; Hillebrand, Olav; Idzik, Krzysztof; Strathmann, Martin; Schiperski, Ferry; Zirlewagen, Johannes; Licha, Tobias

    2013-11-01

    The substantial transformation of the angiotensin II receptor antagonist valsartan to the transformation product 2'-(2H-tetrazol-5-yl)-[1,1'-biphenyl]-4-carboxylic acid (referred to as valsartan acid) during the activated sludge process was demonstrated in the literature and confirmed in the here presented study. However, there was a severe lack of knowledge regarding the occurrence and fate of this compound in surface water and its behavior during drinking water treatment. In this work a comparative study on the occurrence and persistency of valsartan acid, three frequently used β-blockers (metoprolol, atenolol, and sotalol), atenolol acid (one significant transformation product of atenolol and metoprolol), and the two widely distributed persistent anthropogenic wastewater indicators carbamazepine and acesulfame in raw sewage, treated wastewater, surface water, groundwater, and tap water is presented. Median concentrations of valsartan acid in the analyzed matrices were 101, 1,310, 69, <1.0, and 65 ng L(-1), respectively. Treated effluents from wastewater treatment plants were confirmed as significant source. Regarding concentration levels of pharmaceutical residues in surface waters valsartan acid was found just as relevant as the analyzed β-blockers and the anticonvulsant carbamazepine. Regarding its persistency in surface waters it was comparable to carbamazepine and acesulfame. Furthermore, removal of valsartan acid during bank filtration was poor, which demonstrated the relevance of this compound for drinking water suppliers. Regarding drinking water treatment (Muelheim Process) the compound was resistant to ozonation but effectively eliminated (≥90%) by subsequent activated carbon filtration. However, without applying activated carbon filtration the compound may enter the drinking water distribution system as it was demonstrated for Berlin tap water.

  8. TAML/H2O2 Oxidative Degradation of Metaldehyde: Pursuing Better Water Treatment for the Most Persistent Pollutants.

    PubMed

    Tang, Liang L; DeNardo, Matthew A; Gayathri, Chakicherla; Gil, Roberto R; Kanda, Rakesh; Collins, Terrence J

    2016-05-17

    The extremely persistent molluscicide, metaldehyde, widely used on farms and gardens, is often detected in drinking water sources of various countries at concentrations of regulatory concern. Metaldehyde contamination restricts treatment options. Conventional technologies for remediating dilute organics in drinking water, activated carbon, and ozone, are insufficiently effective against metaldehyde. Some treatment plants have resorted to effective, but more costly UV/H2O2. Here we have examined if TAML/H2O2 can decompose metaldehyde under laboratory conditions to guide development of a better real world option. TAML/H2O2 slowly degrades metaldehyde to acetaldehyde and acetic acid. Nuclear magnetic resonance spectroscopy ((1)H NMR) was used to monitor the degradation-the technique requires a high metaldehyde concentration (60 ppm). Within the pH range of 6.5-9, the reaction rate is greatest at pH 7. Under optimum conditions, one aliquot of TAML 1a (400 nM) catalyzed 5% degradation over 10 h with a turnover number of 40. Five sequential TAML aliquots (2 μM overall) effected a 31% removal over 60 h. TAML/H2O2 degraded metaldehyde steadily over many hours, highlighting an important long-service property. The observation of metaldehyde decomposition under mild conditions provides a further indication that TAML catalysis holds promise for advancing water treatment. These results have turned our attention to more aggressive TAML activators in development, which we expect will advance the observed technical performance. PMID:27088657

  9. Ground-water levels and quality data for Georgia

    USGS Publications Warehouse

    ,

    1979-01-01

    This report begins a publication format that will present annually both water-level and water-quality data in Georgia. In this format the information is presented in two-page units: the left page includes text which summarizes the information for an area or subject and the right page consists of one or more illustrations. Daily mean water-level fluctuations and trends are shown in hydrographs for the previous year and fluctuations for the monthly mean water level the previous 10 years for selected observation wells. The well data best illustrate the effects of changes in recharge and discharge in the various ground-water reservoirs in the State. A short narrative explains fluctuations and trends in each hydrograph. (Woodard-USGS)

  10. 8. General view of movable span from water level, showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. General view of movable span from water level, showing piers turntable, movable span, parts of west land span and east viaduct. VIEW NORTHEAST - Broadway Bridge, Spanning Foundry Street, MBTA Yard, Fort Point Channel, & Lehigh Street, Boston, Suffolk County, MA

  11. Water levels of the Ozark aquifer in northern Arkansas, 2013

    USGS Publications Warehouse

    Schrader, Tony P.

    2015-07-13

    Nine hydrographs were selected as representative of the water-level conditions in their respective counties. Wells in Fulton, Izard, and Newton Counties (station names 20N08W27ABD1, 18N09W15BCB1, and 16N21W34ABC1, respectively) have water levels that are within the usual range of values for their respective counties. Wells in Boone, Marion, and Washington Counties (station names 18N19W19BCC1, 19N15W20ACC1, and 16N32W09ABD1, respectively) have water levels that have recently declined or are declining for the period of record. Wells in Benton, Carroll, and Sharp Counties (station names 19N29W07DAA1, 21N26W17BCC1, and 15N05W06DDD1, respectively) have water levels that have been rising recently.

  12. 1. East side of lower dam shown with water level ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. East side of lower dam shown with water level dropped. VIEW WEST - Loleta Recreation Area, Lower Dam, 6 miles Southeast of interesection of State Route 24041 & State Route 66, Loleta, Elk County, PA

  13. Levels and profiles of persistent organic pollutants in resident and migratory birds from an urbanized coastal region of South Korea.

    PubMed

    Hong, Sang Hee; Shim, Won Joon; Han, Gi Myung; Ha, Sung Yong; Jang, Mi; Rani, Manviri; Hong, Sunwook; Yeo, Gwang Yeong

    2014-02-01

    Persistent organic pollutants (POPs) levels in resident and migratory birds collected from an urbanized coastal region of South Korea were investigated. As target species, resident birds that reside in different habitats-such as inland and coastal regions-were selected and their POP contamination status and accumulation features evaluated. Additionally, winter and summer migratory species were analysed for comparison with resident birds. Black-tailed gull and domestic pigeon were selected as the coastal and inland resident birds, respectively, and pacific loon and heron/egret were selected as the winter and summer migratory birds, respectively. The overall POP concentrations (unit: ng/g lipid) in resident birds were 14-131,000 (median: 13,400) for PCBs, 40-284,000 (11,200) for DDTs, <1.0-2850 (275) for CHLs, 23-2020 (406) for HCHs, 2-1520 (261) for HCB, <0.2-48 (5) for pentachlorobenzene (PeCB), 71-7120 (1840) for PBDEs, and <1.8-2300 (408) for HBCDs. In resident birds, the overall level of POPs was higher in seagull compared to pigeon. The stable isotope ratio of nitrogen and carbon indicates that seagull occupies a higher trophic position in the environment than pigeon. However, the POP accumulation profiles in these species differed. Pigeon tends to accumulate more recently used POPs such as PBDEs than seagull. The high-brominated BDE congeners, γ-HBCDs and γ-HCH (also called lindane) were enriched in pigeon compared to seagull, implying the widespread use of Deca-BDE, technical HBCDs, and lindane in the terrestrial environment of South Korea. The different accumulation profile of POPs in both resident species would be related to their habitat difference and trophic positions. For urban resident bird such as pigeon, an intentional intake of dust or soils during feeding is likely to be an additional route of exposure to POPs. Resident birds generally accumulated higher POPs concentrations than migratory birds, the exceptions being relatively volatile compounds

  14. Terrestrial Waters and Sea Level Variations on Interannual Time Scale

    NASA Technical Reports Server (NTRS)

    Llovel, W.; Becker, M.; Cazenave, A.; Jevrejeva, S.; Alkama, R.; Decharme, B.; Douville, H.; Ablain, M.; Beckley, B.

    2011-01-01

    On decadal to multi-decadal time scales, thermal expansion of sea waters and land ice loss are the main contributors to sea level variations. However, modification of the terrestrial water cycle due to climate variability and direct anthropogenic forcing may also affect sea level. For the past decades, variations in land water storage and corresponding effects on sea level cannot be directly estimated from observations because these are almost non-existent at global continental scale. However, global hydrological models developed for atmospheric and climatic studies can be used for estimating total water storage. For the recent years (since mid-2002), terrestrial water storage change can be directly estimated from observations of the GRACE space gravimetry mission. In this study, we analyse the interannual variability of total land water storage, and investigate its contribution to mean sea level variability at interannual time scale. We consider three different periods that, each, depend on data availability: (1) GRACE era (2003-2009), (2) 1993-2003 and (3) 1955-1995. For the GRACE era (period 1), change in land water storage is estimated using different GRACE products over the 33 largest river basins worldwide. For periods 2 and 3, we use outputs from the ISBA-TRIP (Interactions between Soil, Biosphere, and Atmosphere-Total Runoff Integrating Pathways) global hydrological model. For each time span, we compare change in land water storage (expressed in sea level equivalent) to observed mean sea level, either from satellite altimetry (periods 1 and 2) or tide gauge records (period 3). For each data set and each time span, a trend has been removed as we focus on the interannual variability. We show that whatever the period considered, interannual variability of the mean sea level is essentially explained by interannual fluctuations in land water storage, with the largest contributions arising from tropical river basins.

  15. Field concentrations and persistence of polybrominated biphenyls in soils and solubility of PBB in natural waters.

    PubMed Central

    Jacobs, L W; Chou, S F; Tiedje, J M

    1978-01-01

    Soil samples were collected from 28 fields which had received manure from Michigan's most highly contaminated dairy herds. The number of fields in each concentration range of PBB in soil were: 2, not detectable; 15, 0.0 to 8.0 ppb; 6, 14-102 ppb, and 5, 153 to 371 ppb. Plant tissue sampled from the 10 most highly contaminated fields contained no detectable PBB. No evidence of significant degradation of PBB was noted after 1 year incubation in soil. When 14C hexabromobiphenyl and heptabromobiphenyl isomers were incubated in soil less than 0.2% of the 14C was volatilized. Also gas chromatographic analysis of soil extracts showed no difference in recovery of the six major PBB isomers between sterilized and nonsterilized soil. Analysis of these extracts by thin layer chromatography and autoradiography showed no 14C-PBB intermediates. Photodegradation products of the major hexa- and heptabromobiphenyl isomers showed more but still minor (approximately 3%) biodegradation in soil. Much of the photodegradation products appeared bound to soil, since these products could not be extracted from soil. Photodegradation does not appear to be a significant fate of PBB in manures spread on fields since no change was noted in the relative concentrations of isomers in soil samples from our field survey. Studies with distilled, tap, river, and soil waters showed that PBB solubility was markedly influenced by water composition. Images FIGURE 1. FIGURE 2. PMID:209960

  16. Reassortant influenza A viruses in wild duck populations: effects on viral shedding and persistence in water.

    PubMed

    Lebarbenchon, Camille; Sreevatsan, Srinand; Lefèvre, Thierry; Yang, My; Ramakrishnan, Muthannan A; Brown, Justin D; Stallknecht, David E

    2012-10-01

    Wild ducks of the genus Anas represent the natural hosts for a large genetic diversity of influenza A viruses. In these hosts, co-infections with different virus genotypes are frequent and result in high rates of genetic reassortment. Recent genomic data have provided information regarding the pattern and frequency of these reassortant viruses in duck populations; however, potential consequences on viral shedding and maintenance in the environment have not been investigated. On the basis of full-genome sequencing, we identified five virus genotypes, in a wild duck population in northwestern Minnesota (USA), that naturally arose from genetic reassortments. We investigated the effects of influenza A virus genotype on the viral shedding pattern in Mallards (Anas platyrhynchos) and the duration of infectivity in water, under different temperature regimens. Overall, we found that variation in the viral genome composition of these isolates had limited effects on duration, extent and pattern of viral shedding, as well as on the reduction of infectivity in water over time. These results support that, in wild ducks, functionally equivalent gene segments could be maintained in virus populations with no fitness costs when genetic reassortments occur.

  17. Transport and persistence of tylosin-resistant enterococci, genes, and tylosin in soil and drainage water from fields receiving Swine manure.

    PubMed

    Garder, Jason L; Moorman, Thomas B; Soupir, Michelle L

    2014-07-01

    Land application of manure from tylosin-treated swine introduces tylosin, tylosin-resistant enterococci, and erythromycin resistant rRNA methylase () genes, which confer resistance to tylosin. This study documents the persistence and transport of tylosin-resistant enterococci, genes, and tylosin in tile-drained chisel plow and no-till agricultural fields treated with liquid swine manure in alternating years. Between 70 and 100% of the enterococci in manure were resistant to tylosin and B concentrations exceeded 10 copies g manure, while the mean F concentrations exceeded 10 copies g manure (T was not detected). The mean concentration of tylosin was 73 ng g manure. Soil collected from the manure injection band closely following application contained >10 copies g soil of both B and F in 2010 and >10 copies g soil after the 2011 application compared to 3 × 10 to 3 × 10 copies g soil in the no-manure control plots. Gene abundances declined over the subsequent 2-yr period to levels similar to those in the no-manure controls. Concentrations of enterococci in tile water were low, while tylosin-resistant enterococci were rarely detected. In approximately 75% of tile water samples, B was detected, and F was detected in 30% of tile water samples, but levels of these genes were not elevated due to manure application, and no difference was found between tillage practices. These results show that tylosin usage increased the short-term occurrence of tylosin-resistant enterococci, genes, and tylosin in soils but had minimal effect on tile drainage water quality in years of average to below average precipitation.

  18. Transient response of Salix cuttings to changing water level regimes

    NASA Astrophysics Data System (ADS)

    Gorla, L.; Signarbieux, C.; Turberg, P.; Buttler, A.; Perona, P.

    2015-03-01

    Sustainable water management requires an understanding of the effects of flow regulation on riparian ecomorphological processes. We investigated the transient response of Salix viminalis by examining the effect of water-level regimes on its above-ground and below-ground biomass. Four sets of Salix cuttings, three juveniles (in the first growing season) and one mature (1 year old), were planted and initially grown under the same water-level regime for 1 month. We imposed three different water-level regime treatments representing natural variability, a seasonal trend with no peaks, and minimal flow (characteristic of hydropower) consisting of a constant water level and natural flood peaks. We measured sap flux, stem water potential, photosynthesis, growth parameters, and final root architecture. The mature cuttings were not affected by water table dynamics, but the juveniles displayed causal relationships between the changing water regime, plant growth, and root distribution during a 2 month transient period. For example, a 50% drop in mean sap flux corresponded with a -1.5 Mpa decrease in leaf water potential during the first day after the water regime was changed. In agreement with published field observations, the cuttings concentrated their roots close to the mean water table of the corresponding treatment, allowing survival under altered conditions and resilience to successive stress events. Juvenile development was strongly impacted by the minimum flow regime, leading to more than 60% reduction of both above-ground and below-ground biomass, with respect to the other treatments. Hence, we suggest avoiding minimum flow regimes where Salix restoration is prioritized.

  19. Increasing levels of persistent organic pollutants in rainbow trout (Oncorhynchus mykiss) following a mega-flooding episode in the Negro River basin, Argentinean Patagonia.

    PubMed

    Ondarza, Paola M; Gonzalez, Mariana; Fillmann, Gilberto; Miglioranza, Karina S B

    2012-03-01

    In 2006, a severe flooding episode in the Negro River basin, Argentinean Patagonia, occurred and mainly affected the middle valley where lands are devoted to agriculture and soils known to be polluted with persistent organic pollutants. The aim of this study was to estimate the effects of this event on polybrominated diphenyl ethers (PBDEs), endosulfans (α-, β-, sulfate), DDTs (p,p'-DDD, p,p'-DDE, p,p'-DDT) and polychlorinated biphenyls (PCBs) levels in rainbow trout (Oncorhynchus mykiss) tissues. Post-event fish showed higher contaminants levels than pre-event at expenses of all groups. DDTs presented the highest concentrations in all tissues followed by PCBs, endosulfans and PBDEs. The metabolite p,p'-DDE represented about 80% of total DDTs, while PCBs were dominated by penta- and hexa-chlorobiphenyls congeners. BDE-47 was the predominant congener among PBDEs. Endosulfan showed the maximum differences between post- and pre-flood fish (up to 43-fold) with a α-/β- ratio >1, suggesting exposure to fresh technical mixture. Contaminant profiles observed in rainbow trout tissues from both periods (pre- and post-event) were consistent with previous results from water, suspended particle matter and soils, showing that this species is a good biomonitor of aquatic pollution of Negro River basin. The presence of the pesticides in the Negro River system resulted from past and current agricultural practices and it was modified and enhanced by the flooding. Additionally, PCBs and PBDEs occurrence in the aquatic environment deserve more attention, and monitoring programs are recommended in order to diminish their incorporation to aquatic ecosystem.

  20. Persistence of the Intuitive Conception That Heavier Objects Sink More: A Reaction Time Study with Different Levels of Interference

    ERIC Educational Resources Information Center

    Potvin, Patrice; Masson, Steve; Lafortune, Stéphanie; Cyr, Guillaume

    2015-01-01

    Recent research efforts have argued for the "persistence" of some of students' frequent scientific misconceptions, even after correct answers are produced. Some of these studies, based on the analysis of reaction times, have recorded latencies for counter-intuitive or incongruent stimuli compared to intuitive or congruent ones. The…

  1. Strategies for eliminating and reducing persistent bioaccumulative toxic substances: common approaches, emerging trends, and level of success.

    PubMed

    Davies, Kate

    2006-12-01

    This paper reviews nine of the best-known strategies for eliminatine and reducing substances in the category known as "persistent bioaccumulative toxic substances" (PBTSs). The nine strategies are as follows: 1) Ontario's Candidate Substances List for Bans and Phase-outs (1992), 2) Canada's ARET Program (1994), 3) Canada's Toxic Substances Management Policy (1995), 4) the Commission for Environmental Cooperation's Sound Management of Chemicals Initiative (1995), 5) the Great Lakes Binational Toxics Strategy (1997), 6) the U.S. Environmental Protection Agency's (U.S. EPA's) draft National PBT Strategy (1998), 7) U.S. EPA's Waste Minimization Program (1998), 8) the U.N. Stockholm Convention on Persistent Organic Pollutants (2001), and 9) Washington State's Rule on Persistent Bioaccumulative Toxins (2006). The review describes the commonalities among the strategies, including their goals and principles, design approaches, and other common elements. It also discusses several emerging trends, such as the increasing importance of economic considerations, human health information, and nonregulatory management approaches. The paper concludes with a discussion of how effective the strategies have been at achieving their goals of elimination and reduction of persistent bioaccumulative toxic substances.

  2. Assessing the Relationships between Perceived Support from Close Others, Goal Commitment, and Persistence Decisions at the College Level

    ERIC Educational Resources Information Center

    Strom, Renee E.; Savage, Matthew W.

    2014-01-01

    Research on supportive communication was examined in relation to students' goals of earning a college degree and their intent to persist. Theories of student departure (Bean, 1985; Tinto, 1993) informed research questions assessing the impact of how social support from family members and friends affected commitment to the goal of graduation…

  3. Impact of Plumbing Age on Copper Levels in Drinking Water

    EPA Science Inventory

    Theory and limited practical experiences suggest that higher copper levels in drinking water tap samples are typically associated with newer plumbing systems, and levels decrease with increasing plumbing age. Past researchers have developed a conceptual model to explain the “agin...

  4. Effects of water turbidity and salt concentration levels on penetration of solar radiation under water

    SciTech Connect

    Wang, J.; Seyed-Yagoobi, J. )

    1994-05-01

    Two large, outdoor tanks were constructed in order to investigate the effects of water turbidity and salt concentration levels at various depths of water on penetration of solar radiation. These experiments were followed by a laboratory investigation that measured spectral transmittance and the extinction coefficient of water at different salt concentrations and turbidity levels. Both the outdoor and laboratory results indicate that the salt concentration level does not significantly affect solar radiation penetration. However, water clarity, quantified in terms of the turbidity level, plays a critical role on the magnitude of the solar radiation penetration, with the effect of turbidity on penetration increasing with the depth of water. A best-fit model is developed that gives the solar radiation penetration as a function of turbidity level and depth of water.

  5. Analysis for water level data for Everglades National Park, Florida

    USGS Publications Warehouse

    Buchanan, T.J.; Hartwell, J.H.

    1972-01-01

    Stage-duration curves were developed for five gaging stations in Everglades National Park, Florida. Four of the five curves show similar characteristics with an increase in the slope when the water level is below land surface. Monthly stage-duration curves, developed for one of the stations, reflect the seasonal trends of the water level. Recession curves were prepared for the same five stations. These curves represent the average water-level decline during periods of little or no rainfall. They show the decline in level at the end of 10, 20, and 60 days for any given initial stage. A family of curves was also prepared to give the recession from various initial stages for any period up to 60 days.

  6. Global Gray Water Footprint and Water Pollution Levels Related to Anthropogenic Nitrogen Loads to Fresh Water.

    PubMed

    Mekonnen, Mesfin M; Hoekstra, Arjen Y

    2015-11-01

    This is the first global assessment of nitrogen-related water pollution in river basins with a specification of the pollution by economic sector, and by crop for the agricultural sector. At a spatial resolution of 5 by 5 arc minute, we estimate anthropogenic nitrogen (N) loads to freshwater, calculate the resultant gray water footprints (GWFs), and relate the GWFs per river basin to runoff to calculate the N-related water pollution level (WPL) per catchment. The accumulated global GWF related to anthropogenic N loads in the period 2002-2010 was 13×10(12) m3/y. China contributed about 45% to the global total. Three quarters of the GWF related to N loads came from diffuse sources (agriculture), 23% from domestic point sources and 2% from industrial point sources. Among the crops, production of cereals had the largest contribution to the N-related GWF (18%), followed by vegetables (15%) and oil crops (11%). The river basins with WPL>1 (where the N load exceeds the basin's assimilation capacity), cover about 17% of the global land area, contribute about 9% of the global river discharge, and provide residence to 48% of the global population.

  7. Global Gray Water Footprint and Water Pollution Levels Related to Anthropogenic Nitrogen Loads to Fresh Water.

    PubMed

    Mekonnen, Mesfin M; Hoekstra, Arjen Y

    2015-11-01

    This is the first global assessment of nitrogen-related water pollution in river basins with a specification of the pollution by economic sector, and by crop for the agricultural sector. At a spatial resolution of 5 by 5 arc minute, we estimate anthropogenic nitrogen (N) loads to freshwater, calculate the resultant gray water footprints (GWFs), and relate the GWFs per river basin to runoff to calculate the N-related water pollution level (WPL) per catchment. The accumulated global GWF related to anthropogenic N loads in the period 2002-2010 was 13×10(12) m3/y. China contributed about 45% to the global total. Three quarters of the GWF related to N loads came from diffuse sources (agriculture), 23% from domestic point sources and 2% from industrial point sources. Among the crops, production of cereals had the largest contribution to the N-related GWF (18%), followed by vegetables (15%) and oil crops (11%). The river basins with WPL>1 (where the N load exceeds the basin's assimilation capacity), cover about 17% of the global land area, contribute about 9% of the global river discharge, and provide residence to 48% of the global population. PMID:26440220

  8. Subsidence at the Fairport Harbor Water Level Gauge

    NASA Astrophysics Data System (ADS)

    Conner, D. A.

    2014-12-01

    SUBSIDENCE AT THE FAIRPORT HARBOR WATER LEVEL GAUGE I will provide information on methods being used to monitor Lake Erie water levels and earth movement at Fairport Harbor, Ohio. Glacial Isostatic Adjustment (GIA) is responsible for vertical movement throughout the Great Lakes region. Fairport Harbor is also experiencing vertical movement due to salt mining, so the nearby water level gauge operated by the National Oceanic and Atmospheric Administration (NOAA) is affected by both GIA and mining. NOAA's National Geodetic Survey (NGS) defines and maintains the National Spatial Reference System (NSRS). The NSRS includes a network of permanently marked points; a consistent, accurate, and up-to-date national shoreline; a network of Continuously Operating Reference Stations (CORS) which supports three-dimensional positioning activities; and a set of accurate models describing dynamic, geophysical processes that affect spatial measurements. The NSRS provides the spatial reference foundation for transportation, mapping, charting and a multitude of scientific and engineering applications. Fundamental elements of geodetic infrastructure include GPS CORS (3-D), water level and tide gauges (height) and a system of vertical bench marks (height). When two or more of these elements converge they may provide an independent determination of position and vertical stability as is the case here at the Fairport Harbor water level gauge. Analysis of GPS, leveling and water level data reveal that this gauge is subsiding at about 2-3 mm/year, independent of the effects of GIA. Analysis of data from the nearby OHLA GPS CORS shows it subsiding at about 4 mm/yr, four times faster than expected due to GIA alone. A long history of salt mine activity in the area is known to geologists but it came as a surprise to other scientists.

  9. Predicting Atrazine Levels in Water Utility Intake Water for MCL Compliance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To protect human health, atrazine concentrations in drinking water must not exceed its maximum contaminant level (MCL) of 3 ug/L. The United States Environmental Protection Agency (USEPA) mandates that municipal water providers sample quarterly to determine MCL compliance. Atrazine levels were mon...

  10. Climate change and prairie pothole wetlands: mitigating water-level and hydroperiod effects through upland management

    USGS Publications Warehouse

    Renton, David A.; Mushet, David M.; DeKeyser, Edward S.

    2015-01-01

    Prairie pothole wetlands offer crucial habitat for North America’s waterfowl populations. The wetlands also support an abundance of other species and provide ecological services valued by society. The hydrology of prairie pothole wetlands is dependent on atmospheric interactions. Therefore, changes to the region’s climate can have profound effects on wetland hydrology. The relevant literature related to climate change and upland management effects on prairie pothole wetland water levels and hydroperiods was reviewed. Climate change is widely expected to affect water levels and hydroperiods of prairie pothole wetlands, as well as the biota and ecological services that the wetlands support. In general, hydrologic model projections that incorporate future climate change scenarios forecast lower water levels in prairie pothole wetlands and longer periods spent in a dry condition, despite potential increases in precipitation. However, the extreme natural variability in climate and hydrology of prairie pothole wetlands necessitates caution when interpreting model results. Recent changes in weather patterns throughout much of the Prairie Pothole Region have been in increased precipitation that results in increased water inputs to wetlands above losses associated with warmer temperatures. However, observed precipitation increases are within the range of natural climate variability and therefore, may not persist. Identifying management techniques with the potential to affect water inputs to prairie pothole wetlands would provide increased options for managers when dealing with the uncertainties associated with a changing climate. Several grassland management techniques (for example, grazing and burning) have the potential to affect water levels and hydroperiods of prairie pothole by affecting infiltration, evapotranspiration, and snow deposition.

  11. Passive Sampling to Measure Baseline Dissolved Persistent Organic Pollutant Concentrations in the Water Column of the Palos Verdes Shelf Superfund Site

    EPA Science Inventory

    Passive sampling was used to deduce water concentrations of persistent organic pollutants (POPs) in the vicinity of a marine Superfund site on the Palos Verdes Shelf, California, USA. Pre-calibrated solid phase microextraction (SPME) fibers and polyethylene (PE) strips that were...

  12. Hydrogeology and Simulation of Regional Ground-Water-Level Declines in Monroe County, Michigan

    USGS Publications Warehouse

    Reeves, Howard W.; Wright, Kirsten V.; Nicholas, J.R.

    2004-01-01

    determination of inputs and outputs of water-leakage from glacial deposits and flows across model boundaries. The imposed demands on the groundwater system create additional discharge from the bedrock aquifer, and this discharge is documented by records and estimates of water use including: residential and industrial use, irrigation, and quarry dewatering. Hydrologic characterization of Monroe County and surrounding areas was used to determine the model boundaries and inputs within the ground-water model. MODFLOW-2000 was the computer model used to simulate ground-water flow. Predevelopment, 1991, and 2001 conditions were simulated with the model. The predevelopment model did not include modern water use and was compared to information from early settlement of the county. The 1991 steady-state model included modern demands on the ground-water system and was based on a significant amount of data collected for this and previous studies. The predevelopment and 1991 simulations were used to calibrate the numerical model. The simulation of 2001 conditions was based on recent data and explored the potential ground-water levels if the current conditions persist. Model results indicate that the ground-water level will stabilize in the county near current levels if the demands imposed during 2001 are held constant.

  13. Processes affecting the transport of Cryptosporidium parvum and other persistent pathogens in surface- and ground-waters

    NASA Astrophysics Data System (ADS)

    Packman, A. I.; Lau, B. L.; Harter, T.; Atwill, E. R.

    2007-12-01

    Waterborne diseases are transmitted through numerous environmental pathways, and their migration is strongly mediated by interaction with a wide variety of sediments and other natural materials during transport. Here we provide an overview of factors that affect the fate of persistent water-borne pathogens, focusing particularly on the zoonotic pathogen Cryptosporidium parvum as an example. While individual microbial cells are both small and have low specific gravity, suggesting that they should be highly mobile and remain suspended for long periods of time, attachment to a variety of background materials can substantially reduce pathogen mobility. Cryptosporidium oocysts readily associate with both inorganic and organic particles, resulting in the formation of aggregates. This process tends to increase the effective settling velocity of C. parvum in surface waters. Similarly, pathogens readily become associated with the solid matrix during transport in groundwater, resulting in removal by filtration. However, this process is reversible with C. parvum, resulting in a slow long-term release following the initial deposition. Pathogens also become associated with biofilms, which are surface-attached communities of microorganisms in a gelatinous matrix. The presence of biofilms increases the immobilization and retention of Cryptosporidium on solid surfaces. All of these processes influence pathogen transmission in surface waters such as rivers and water-supply canals. In these environments, pathogens can be immobilized by deposition into stable sediment beds by a combination of gravitational sedimentation and advection into pore waters followed by subsurface filtration. Association with background suspended matter tends to increase pathogen deposition by sedimentation, and the presence of benthic (sedimentary) biofilms also tends to increase pathogen retention. For pathogens that remain viable for long periods of time in natural aquatic systems, as is the case with

  14. Effect of vitamin A and Zn supplementation on indices of vitamin A status, haemoglobin level and defecation of children with persistent diarrhea

    PubMed Central

    Wang, Yuting; Gao, Yuan; Liu, Quanbo; Zhan, Xue; Li, Zhongyue; Hu, Huajian; Li, Tingyu; Chen, Jie

    2016-01-01

    To investigate the effect of vitamin A and Zn supplementation on vitamin A status, haemoglobin level and defecation of children with persistent diarrhea, a total of 160 paediatric patients were randomly assigned to one of four intervention groups: daily supplementation of 1,500 IU VA for 14 days; daily Zn supplementation for 14 days; daily supplementation with both VA and Zn for 14 days; no supplementation. One hundred twenty-seven children with persistent diarrhea finished intervention (33 were lost to follow-up). Among the 127 children, 41 (32.28%) had anaemia, 104 (81.89%) had a VA deficiency and 38 (29.92%) had an iron insufficiency. Supplementation with VA or VA + Zn enhanced the serum VA levels and ameliorated anaemia. Supplementation with Zn and VA + Zn for 5 days significantly improved defecation, where the VA + Zn treatment resulted in superior outcomes. After 14 days of intervention, the total effectiveness rates were 93.94%, 96.77% and 96.67% in the three groups, significantly greater than that of the non-supplementation group (72.73%). These results indicate that single VA or concurrent VA + Zn supplementation can improve vitamin A status, haemoglobin level and defecation. However, concurrent VA + Zn supplementation is the optimal option and can shorten the duration of persistent diarrhea and markedly improve nutritional status. (www.clinicaltrials.gov registration number: ChiCTR-IOR-14005498) PMID:27499581

  15. Effect of vitamin A and Zn supplementation on indices of vitamin A status, haemoglobin level and defecation of children with persistent diarrhea.

    PubMed

    Wang, Yuting; Gao, Yuan; Liu, Quanbo; Zhan, Xue; Li, Zhongyue; Hu, Huajian; Li, Tingyu; Chen, Jie

    2016-07-01

    To investigate the effect of vitamin A and Zn supplementation on vitamin A status, haemoglobin level and defecation of children with persistent diarrhea, a total of 160 paediatric patients were randomly assigned to one of four intervention groups: daily supplementation of 1,500 IU VA for 14 days; daily Zn supplementation for 14 days; daily supplementation with both VA and Zn for 14 days; no supplementation. One hundred twenty-seven children with persistent diarrhea finished intervention (33 were lost to follow-up). Among the 127 children, 41 (32.28%) had anaemia, 104 (81.89%) had a VA deficiency and 38 (29.92%) had an iron insufficiency. Supplementation with VA or VA + Zn enhanced the serum VA levels and ameliorated anaemia. Supplementation with Zn and VA + Zn for 5 days significantly improved defecation, where the VA + Zn treatment resulted in superior outcomes. After 14 days of intervention, the total effectiveness rates were 93.94%, 96.77% and 96.67% in the three groups, significantly greater than that of the non-supplementation group (72.73%). These results indicate that single VA or concurrent VA + Zn supplementation can improve vitamin A status, haemoglobin level and defecation. However, concurrent VA + Zn supplementation is the optimal option and can shorten the duration of persistent diarrhea and markedly improve nutritional status. (www.clinicaltrials.gov registration number: ChiCTR-IOR-14005498).

  16. Effect of vitamin A and Zn supplementation on indices of vitamin A status, haemoglobin level and defecation of children with persistent diarrhea.

    PubMed

    Wang, Yuting; Gao, Yuan; Liu, Quanbo; Zhan, Xue; Li, Zhongyue; Hu, Huajian; Li, Tingyu; Chen, Jie

    2016-07-01

    To investigate the effect of vitamin A and Zn supplementation on vitamin A status, haemoglobin level and defecation of children with persistent diarrhea, a total of 160 paediatric patients were randomly assigned to one of four intervention groups: daily supplementation of 1,500 IU VA for 14 days; daily Zn supplementation for 14 days; daily supplementation with both VA and Zn for 14 days; no supplementation. One hundred twenty-seven children with persistent diarrhea finished intervention (33 were lost to follow-up). Among the 127 children, 41 (32.28%) had anaemia, 104 (81.89%) had a VA deficiency and 38 (29.92%) had an iron insufficiency. Supplementation with VA or VA + Zn enhanced the serum VA levels and ameliorated anaemia. Supplementation with Zn and VA + Zn for 5 days significantly improved defecation, where the VA + Zn treatment resulted in superior outcomes. After 14 days of intervention, the total effectiveness rates were 93.94%, 96.77% and 96.67% in the three groups, significantly greater than that of the non-supplementation group (72.73%). These results indicate that single VA or concurrent VA + Zn supplementation can improve vitamin A status, haemoglobin level and defecation. However, concurrent VA + Zn supplementation is the optimal option and can shorten the duration of persistent diarrhea and markedly improve nutritional status. (www.clinicaltrials.gov registration number: ChiCTR-IOR-14005498). PMID:27499581

  17. Knickpoint Generation and Persistence Following Base-Level Fall: An Examination of Erosional Thresholds in Sediment Flux Dependent Erosion Models

    NASA Astrophysics Data System (ADS)

    Crosby, B. T.; Whipple, K. X.; Gasparini, N. M.; Wobus, C. W.

    2005-12-01

    Non-lithologic knickpoints, or discrete convexities in longitudinal river profiles, are commonly considered to be the mobile, upstream extent of a transient incisional signal. Downstream of the knickpoint, the landscape is responding to a recent change in base level, uplift rate or climatic condition, while upstream of the knickpoint, the landscape retains its relict form, relatively ignorant the transient signal. Though this model of knickpoint mobility and their capacity to communicate incisional signals throughout basins works well with standard formulations of the stream power erosion model, the recent development of sediment flux dependent erosion models contain explicit thresholds that limit the upstream extent of knickpoint-mediated fluvial adjustment. Sediment flux dependent erosion models fail to communicate incisional signals at small drainage areas as sediment and water discharges are insufficient to effectively erode the bed. As well, if knickpoint slopes increase beyond a threshold value, sediment impacts against the bed become too infrequent and too oblique to continue knickpoint propagation by fluvial mechanisms. This threshold in fluvial erosion could lead to the stagnation of incisional signals and the generation of hanging valleys. This theoretical expectation aligns with our observation that in numerous actively incising landscapes around the world, relict low drainage area basins are often found elevated high above and disconnected from the mainstem by extremely over-steepened channel reaches often composed of one or more near-vertical steps. In order to better understand how river networks respond during transient pulses of incision, we employ a numerical landscape evolution model (CHILD) to test the sensitivity of three different sediment flux dependent erosion models to different base-level fall scenarios. This technique allows us to observe the propagation of the signal throughout a fluvial network composed of tributaries of variable

  18. Wii mote as hydrological sensor: observation of water level fluctuations

    NASA Astrophysics Data System (ADS)

    Luxemburg, W.; Hut, R.; Weijs, S.; Hegnauer, M.

    2009-12-01

    The input device of the Nintendo Wii, the Wii-mote offers scientist a multitude of cheap, high quality sensors; ideal for proof of concept testing. For a specific application, i.e. the water level fluctuation in a floating evaporation pan the Wii-mote was tested as the observing device. It is shown that the controller can observe movements with high enough temporal and spatial resolution of up to 4 infrared LED’s to describe water level movements. Floating pans positioned in lakes and reservoirs better represent open water evaporation than evaporation pans installed on land. On the other hand performing water level measurements in a floating pan is more complicated due to movement of the pan and wave activities in the pan. The Wii-mote was mounted on the side of a standard class A-pan and a float was placed in the middle of the pan, with 4 LED’s on top moving along a fixed bar. The information that the Wii-mote wirelessly sends by blue tooth was captured on a laptop. With a MATLAB routine this data was converted into movement of the LED’s relatively to the controller. The observations show that wave activities are nicely captured with a typical spatial resolution smaller than 0.1 mm in our set-up and a temporal resolution of maximum 100 Hz. A frequency domain filter was applied to the observed datasets to obtain average water levels. In our laboratory setting the pan was placed in a large basin with a wave generator. A constant, but small, rate of water was added to the evaporation pan. The average pan levels from the filtered datasets showed systematically lower levels compared to the level without any wave activities. This is a typical effect of waves that occur in shallow basins. However, the added water with rates up to 5 mm/hour were clearly recognized in the filtered datasets which indicates that the Wii-mote is very well capable as a sensor for water level observations.

  19. Status of water levels and selected water-quality conditions in the Mississippi River Valley Alluvial Aquifer in Eastern Arkansas, 2002

    USGS Publications Warehouse

    Reed, T.B.

    2004-01-01

    During the spring of 2002, water levels were measured in 737 wells completed in the Mississippi River Valley alluvial aquifer in eastern Arkansas. The regional direction of groundwater flow is generally to the south and east except where affected by intense ground-water withdrawals. In 2002, the highest water-level altitude measured was 287 feet above National Geodetic Vertical Datum of 1929 in northeastern Clay County. The lowest water-level altitude measured was 78 feet above National Geodetic Vertical Datum of 1929 in southwestern Ashley County. Comparisons of water-level changes in cones of depression from 1998 to 2002 show increases and decreases in depth or areal extent. A large depression in the potentiometric surface was located in Arkansas, Lonoke, and Prairie Counties during 1998 and persisted in 2002. Water levels generally declined in this depression in Lonoke County but rose in Arkansas County. Two shallower cones of depressions were located in Craighead, Cross, and Poinsett Counties and St. Francis, Woodruff, Lee, and Monroe Counties west of Crowleys Ridge during 1998. These coalesced into a single depression by 2002. Water-level data from 143 wells with 26 or more years of record indicate long-term water levels in the alluvial aquifer declined an average of about 0.3 foot per year from 1977 to 2002. Water levels generally declined throughout most of the aquifer from 1998 to 2002. Specific conductance measurements made on water samples collected from 64 wells ranged from 262 microsiemens per centimeter in a well in Randolph County to 2,730 microsiemens per centimeter in a well in Chicot County.

  20. Persistence of F-Specific RNA Coliphages in Surface Waters from a Produce Production Region along the Central Coast of California.

    PubMed

    Ravva, Subbarao V; Sarreal, Chester Z

    2016-01-01

    F+ RNA coliphages (FRNA) are used to source-track fecal contamination and as surrogates for enteric pathogen persistence in the environment. However, the environmental persistence of FRNA is not clearly understood and necessitates the evaluation of the survival of prototype and environmental isolates of FRNA representing all four genogroups in surface waters from the central coast of California. Water temperature played a significant role in persistence-all prototype and environmental strains survived significantly longer at 10 °C compared to 25 °C. Similarly, the availability of host bacterium was found to be critical in FRNA survival. In the absence of E. coli F(amp), all prototypes of FRNA disappeared rapidly with a D-value (days for one log reduction) of <1.2 d from water samples incubated at 25 °C; the longest surviving prototype was SP. However, in the presence of the host, the order of persistence at 25 °C was QB>MS2>SP>GA and at 10 °C it was QB = MS2>GA>SP. Significant differences in survival were observed between prototypes and environmental isolates of FRNA. While most environmental isolates disappeared rapidly at 25 °C and in the absence of the host, members of genogroups GIII and GI persisted longer with the host compared to members of GII and GIV. Consequentially, FRNA based source tracking methods can be used to detect phages from recent fecal contamination along with those that persist longer in the environment as a result of cooler temperatures and increased host presence. PMID:26784030

  1. AUTOMATED WATER LEVEL MEASUREMENTS IN SMALL-DIAMETER AQUIFER TUBES

    SciTech Connect

    PETERSEN SW; EDRINGTON RS; MAHOOD RO; VANMIDDLESWORTH PE

    2011-01-14

    Groundwater contaminated with hexavalent chromium, strontium-90, and uranium discharges into the Columbia River along approximately 16 km (10 mi) of the shoreline. Various treatment systems have and will continue to be implemented to eliminate the impact of Hanford Site contamination to the river. To optimize the various remediation strategies, it is important to understand interactions between groundwater and the surface water of the Columbia River. An automated system to record water levels in aquifer sampling tubes installed in the hyporheic zone was designed and tested to (1) gain a more complete understanding of groundwater/river water interactions based on gaining and losing conditions ofthe Columbia River, (2) record and interpret data for consistent and defensible groundwater/surface water conceptual models that may be used to better predict subsurface contaminant fate and transport, and (3) evaluate the hydrodynamic influence of extraction wells in an expanded pump-and-treat system to optimize the treatment system. A system to measure water levels in small-diameter aquifer tubes was designed and tested in the laboratory and field. The system was configured to allow manual measurements to periodically calibrate the instrument and to permit aquifer tube sampling without removing the transducer tube. Manual measurements were collected with an e-tape designed and fabricated especially for this test. Results indicate that the transducer system accurately records groundwater levels in aquifer tubes. These data are being used to refine the conceptual and numeric models to better understand interactions in the hyporheic zone of the Columbia River and the adjacent river water and groundwater, and changes in hydrochemistry relative to groundwater flux as river water recharges the aquifer and then drains back out in response to changes in the river level.

  2. Effects of Irrigation, Drought, and Ground-Water Withdrawals on Ground-Water Levels in the Southern Lihue Basin, Kauai, Hawaii

    USGS Publications Warehouse

    Izuka, Scot K.

    2006-01-01

    A numerical ground-water-flow model was used to investigate the effects of irrigation on ground-water levels in the southern Lihue Basin, Kauai, Hawaii, and the relation between declining ground-water levels observed in the basin in the 1990s and early 2000s and concurrent drought, irrigation reduction, and changes in ground-water withdrawal. Results of steady-state model simulations indicate that changing from pre-development to 1981 irrigation and ground-water-withdrawal conditions could, given enough time for steady state to be achieved, raise ground-water levels in some areas of the southern Lihue Basin by as much as 200 feet, and that changing from 1981 to 1998 irrigation and ground-water-withdrawal conditions could lower ground-water levels in some areas by as much as 100 feet. Transient simulations combining drought, irrigation reduction, and changes in ground-water withdrawal show trends that correspond with those observed in measured water levels. Results of this study indicate that irrigation reduction was the primary cause of the observed decline in ground-water-levels. In contrast, ground-water withdrawal had a long-duration but small-magnitude effect, and drought had a widespread, high-magnitude but short-duration effect. Inasmuch as irrigation in the future is unlikely to return to the same levels as during the period of peak sugarcane agriculture, the decline in ground-water levels resulting from the reduction and ultimate end of sugarcane irrigation can be considered permanent. Assuming that irrigation does not return to the southern Lihue Basin and that, on average, normal rainfall persists and ground-water withdrawal remains at 1998 rates, model projections indicate that average ground-water levels in the Kilohana-Puhi area will continue to recover from the drought of 1998-2002 and eventually rise to within about 4 feet of the pre-drought conditions. Long-term climate trends, increases in ground-water withdrawal, or other factors not simulated in

  3. The effects of water levels on Two Lake Ontario Wetlands

    USGS Publications Warehouse

    Busch, Wolf-Dieter N.; Osborn, Ronald G.; Auble, Gregor T.

    1990-01-01

    Lake Ontario's water levels have been regulated since 1959, after the completion of the St. Lawrence River navigation and hydropower development project. The plan used to guide the regulation (1958-D) has been in effect since 1963 (Bryce, 1982). The purpose of the regulation was to prevent extreme high-water levels which increased erosion on the south shore of Lake Ontario, while protecting the interests of commercial navigation and hydropower production in the St. Lawrence River (T. Brown, personal communication, member of the Board of Control). Major user groups have sought further reductions in the range of lake level fluctuations. However, the biological resources, especially the lake influenced wetlands, benefit from the waterlevel fluctuations. Great Lakes wetlands are the most important habitat for wildlife of the region (Tilton and Schwegler, 1978). We provide information here on the responses of wetland plant communities in two wetlands to changes in lake levels over time.

  4. Relation of drainage problems to high ground-water levels, Coconut Grove area, Oahu, Hawaii

    USGS Publications Warehouse

    Swain, L.A.; Huxel, C.J.

    1971-01-01

    Purpose and Scope In 1969, hydrologic data-collection sites were established in and around the Coconut Grove area for the purpose of measuring directly the relationship between rainfall, runoff, ground-water levels, the level of water in Kawainui Swamp and the canals, and tidal fluctuations. The primary objective was to identify the causes of the occurrence and persistence of flooding and to gain data on which to base recommendations for remedial action. The scope of the study included establishing and operating flow and stage-recording gages on the Swamp, Kawainui Canal, and the inner canal; periodic and repeated measurements of ground-water level in test borings throughout the residential area; collection and analysis of soil and construction borings made for engineering purposes; the assembly and analysis of all available data relating surface and subsurface flow conditions, and the development of conclusions as to the causes and means to alleviate the flooding. This report summarizes the information collected from October 1969 to June 1971, includes analysis of the data, and discusses the probable causes of flooding.

  5. Persistent At-Level Thermal Hyperalgesia and Tactile Allodynia Accompany Chronic Neuronal and Astrocyte Activation in Superficial Dorsal Horn following Mouse Cervical Contusion Spinal Cord Injury

    PubMed Central

    Watson, Jaime L.; Hala, Tamara J.; Putatunda, Rajarshi; Sannie, Daniel; Lepore, Angelo C.

    2014-01-01

    In humans, sensory abnormalities, including neuropathic pain, often result from traumatic spinal cord injury (SCI). SCI can induce cellular changes in the CNS, termed central sensitization, that alter excitability of spinal cord neurons, including those in the dorsal horn involved in pain transmission. Persistently elevated levels of neuronal activity, glial activation, and glutamatergic transmission are thought to contribute to the hyperexcitability of these dorsal horn neurons, which can lead to maladaptive circuitry, aberrant pain processing and, ultimately, chronic neuropathic pain. Here we present a mouse model of SCI-induced neuropathic pain that exhibits a persistent pain phenotype accompanied by chronic neuronal hyperexcitability and glial activation in the spinal cord dorsal horn. We generated a unilateral cervical contusion injury at the C5 or C6 level of the adult mouse spinal cord. Following injury, an increase in the number of neurons expressing ΔFosB (a marker of chronic neuronal activation), persistent astrocyte activation and proliferation (as measured by GFAP and Ki67 expression), and a decrease in the expression of the astrocyte glutamate transporter GLT1 are observed in the ipsilateral superficial dorsal horn of cervical spinal cord. These changes have previously been associated with neuronal hyperexcitability and may contribute to altered pain transmission and chronic neuropathic pain. In our model, they are accompanied by robust at-level hyperaglesia in the ipsilateral forepaw and allodynia in both forepaws that are evident within two weeks following injury and persist for at least six weeks. Furthermore, the pain phenotype occurs in the absence of alterations in forelimb grip strength, suggesting that it represents sensory and not motor abnormalities. Given the importance of transgenic mouse technology, this clinically-relevant model provides a resource that can be used to study the molecular mechanisms contributing to neuropathic pain

  6. Politics of innovation in multi-level water governance systems

    NASA Astrophysics Data System (ADS)

    Daniell, Katherine A.; Coombes, Peter J.; White, Ian

    2014-11-01

    Innovations are being proposed in many countries in order to support change towards more sustainable and water secure futures. However, the extent to which they can be implemented is subject to complex politics and powerful coalitions across multi-level governance systems and scales of interest. Exactly how innovation uptake can be best facilitated or blocked in these complex systems is thus a matter of important practical and research interest in water cycle management. From intervention research studies in Australia, China and Bulgaria, this paper seeks to describe and analyse the behind-the-scenes struggles and coalition-building that occurs between water utility providers, private companies, experts, communities and all levels of government in an effort to support or block specific innovations. The research findings suggest that in order to ensure successful passage of the proposed innovations, champions for it are required from at least two administrative levels, including one with innovation implementation capacity, as part of a larger supportive coalition. Higher governance levels can play an important enabling role in facilitating the passage of certain types of innovations that may be in competition with currently entrenched systems of water management. Due to a range of natural biases, experts on certain innovations and disciplines may form part of supporting or blocking coalitions but their evaluations of worth for water system sustainability and security are likely to be subject to competing claims based on different values and expertise, so may not necessarily be of use in resolving questions of "best courses of action". This remains a political values-based decision to be negotiated through the receiving multi-level water governance system.

  7. Decline in water level boosts cyanobacteria dominance in subtropical reservoirs.

    PubMed

    Yang, Jun; Lv, Hong; Yang, Jun; Liu, Lemian; Yu, Xiaoqing; Chen, Huihuang

    2016-07-01

    Globally aquatic ecosystems are likely to become more vulnerable to extreme water fluctuation rates due to the combined effects of climate change and human activity. However, relatively little is known about the importance of water level fluctuations (WLF) as a predictor of phytoplankton community shifts in subtropical reservoirs. In this study, we used one year of data (2010-2011) from four subtropical reservoirs of southeast China to quantify the effects of WLF and other environmental variables on phytoplankton and cyanobacteria dynamics. The reservoirs showed an apparent switch between a turbid state dominated by cyanobacteria and a clear state dominated by other non-cyanobacterial taxa (e.g., diatoms, green algae). Cyanobacterial dominance decreased, or increased, following marked changes in water level. Multiple regression analysis demonstrated that pH, euphotic depth, WLF, and total phosphorus provided the best model and explained 30.8% of the variance in cyanobacteria biomass. Path analysis showed that positive WLF (i.e. an increase in water level) can reduce the cyanobacteria biomass either directly by a dilution effect or indirectly by modifying the limnological conditions of the reservoirs in complex pathways. To control the risk of cyanobacterial dominance or blooms, WLF should be targeted to be above +2m/month; that is an increase in water level of 2m or more. Given that WLF is likely to be of more frequent occurrence under future predicted conditions of climate variability and human activity, water level management can be widely used in small and medium-sized reservoirs to prevent the toxic cyanobacterial blooms and to protect the ecosystem integrity or functions. PMID:27016690

  8. Effect of Increased Water Vapor Levels on TBC Lifetime

    SciTech Connect

    Pint, Bruce A; Garner, George Walter; Lowe, Tracie M; Haynes, James A; Zhang, Ying

    2011-01-01

    To investigate the effect of increased water vapor levels on thermal barrier coating (TBC) lifetime, furnace cycle tests were performed at 1150 C in air with 10 vol.% water vapor (similar to natural gas combustion) and 90 vol.%. Either Pt diffusion or Pt-modified aluminide bond coatings were applied to specimens from the same batch of a commercial second-generation single-crystal superalloy and commercial vapor-deposited yttria-stabilized zirconia (YSZ) top coats were applied. Three coatings of each type were furnace cycled to failure to compare the average lifetimes obtained in dry O{sub 2}, using the same superalloy batch and coating types. Average lifetimes with Pt diffusion coatings were unaffected by the addition of water vapor. In contrast, the average lifetime of Pt-modified aluminide coatings was reduced by more than 50% with 10% water vapor but only slightly reduced by 90% water vapor. Based on roughness measurements from similar specimens without a YSZ coating, the addition of 10% water vapor increased the rate of coating roughening more than 90% water vapor. Qualitatively, the amount of {beta}-phase depletion in the coatings exposed in 10% water vapor did not appear to be accelerated.

  9. Water-quality and ground-water-level data, Bernalillo County, central New Mexico, 1995

    USGS Publications Warehouse

    Rankin, D.R.

    1996-01-01

    Water-quality and ground-water-level data were collected in two areas of eastern Bernalillo County in central New Mexico between March and July of 1995. Fifty-one wells, two springs, and the Ojo Grande Acequia in the east mountain area of Bernalillo County and nine wells in the northeast area of the city of Albuquerque were sampled. The water samples were analyzed for selected nutrient species; total organic carbon; major dissolved constituents; dissolved arsenic, boron, iron, and manganese; and methylene blue active substances. Analytical results were used to compute hardness, sodium adsorption ratio, and dissolved solids. Specific conductance, pH, temperature, and alkalinity were measured in the field at the time of sample collection. Ground- water-level and well-depth measurements were made at the time of sample collection when possible. Water-quality data, ground- water-level data, and well-depth data are presented in tabular form.

  10. Persistent organic pollutants in the natural environments of the city of Bratsk (Irkutsk Oblast): Levels and risk assessment

    NASA Astrophysics Data System (ADS)

    Mamontova, E. A.; Tarasova, E. N.; Mamontov, A. A.

    2014-11-01

    The contents of persistent organic pollutants (POPs)—polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs)—in the natural environments of an industrial city (Bratsk) of Irkutsk oblast have been studied. Features of the spatial and seasonal distribution of the PCBs and OCPs in the soils and the atmospheric air have been revealed. The structure of the homological and congeneric composition of the PCBs in the soils and the atmospheric air has been shown. Parameters of the carcinogenic and noncarcinogenic risks for human health from the impact of the PCBs and OCPs present in the soils and the atmospheric air have been determined.

  11. Using silicates to lower lead levels in drinking water

    SciTech Connect

    Not Available

    1994-09-01

    York is a small resort town on the coast of Maine, near the New Hampshire border. The town's population of 5,000 usually doubles during the summer tourist season. Like many small water systems in New England, its soft, moderately alkaline water corrodes its unlined, cast-iron pipe distribution system, picking up significant quantities of iron along the way. Customers served by these lines have complained about the red water. York Water District officials hoped that a new 4-mgd treatment facility brought into service in spring 1990 would alleviate the red water problems, but they were also considering ways to address the requirements of the Lead and Copper Rule from the EPA promulgated in 1991. With the assistance of their consulting engineering firm, York Water District officials evaluated treatment strategies and decided against using polyphosphates to control lead and copper because of their ability to complex with the metals, possibly causing an increase in concentration. The officials eventually chose sodium silicates to lower the iron, lead, and copper levels in the system. Several utilities in Maine had reported using sodium silicate as a common strategy for red water problems. In addition, sodium silicate was favored because it reacts with metal for form a barrier to corrosion. York Water District, with assistance from its consultant, designed an 18-month program to add sodium silicates to its system, track metal concentrations, and monitor red water complaints. The district prepared a report for the EPA, covering data collected over the first 12 months of the program -- essentially calendar year 1991. According to Michael R. Schock, research chemist with the EPA's Drinking Water Research Division in Cincinnati, the agency is anxious to obtain as much quantitative information as possible on using sodium silicate for pH and/or corrosion control. This article describes the monitoring system, water treatment and study results.

  12. The response of mire vegetation to water level drawdown

    NASA Astrophysics Data System (ADS)

    Kurki, Kirsi; Laine, Jukka; Vasander, Harri; Tuittila, Eeva-Stiina

    2010-05-01

    Mires have a significant role in climate change mitigation due to their enormous carbon storage and due to the fluxes of greenhouse gases between ecosystem and the atmosphere. Mire vegetation is controlled by ecohydrology, climate and by the competition of plants on light and nutrients. The water logged conditions create a challenging environment for both vascular plants and bryophytes; therefore majority of plants growing in these habitats are highly specialized. Global warming is predicted to affect mire vegetation indirectly through increased evapotranspiration leading to decreased water table levels down to 14-22 centimeters. Water level drawdown is likely to affect the vegetation composition and consequently the ecosystem functioning of mires. Previous studies covering the first years following water table level drawdown have shown that vascular plants benefit from a lower water table and hollow-specific Sphagnum species suffer. In addition to changes in plant abundances the diversity of plant communities decreases. The lawn and hollow communities of Sphagna and sedges are found to be the most sensitive plant groups. It has been shown that surveys on vegetation changes can have different results depending on the time scale. The short and long term responses are likely vary in heterogenous mire vegetation; therefore predictions can be done more reliably with longer surveys. We applied BACI (before-after-control-impact) experimental approach to study the responses of different functional mire plant groups to water level drawdown. There are 3 control plots, 3 treatment plots with moderate water level drawdown and 3 plots drained for forestry 40 years ago as a reference. The plots are located in meso-, oligo- and ombrotrophic sites in Lakkasuo (Orivesi, Finland). The vegetation was surveyed from permanent sampling points before ditching in 2000 and during the years 2001-2003 and 2009. The data was analyzed with NMDS (PC-Ord) and DCA (CANOCO). Overall results show

  13. Influence of nutrient level on methylmercury content in water spinach.

    PubMed

    Greger, Maria; Dabrowska, Beata

    2010-08-01

    Widely consumed vegetables are often cultivated in sewage waters with high nutrient levels. They can contain high levels of methylmercury (MeHg), because they can form MeHg from inorganic Hg in their young shoots. We determined whether the MeHg uptake and the MeHg formation in the shoots of water spinach (Ipomoea aquatica) were affected by the presence of a high nutrient level in the growth medium. Water spinach shoots were rooted and pretreated in growth medium containing 7% (low) or 70% (high) Hoagland nutrient solution; thereafter, the plants were treated with either 0.02 microM MeHg or 0.2 microM HgCl2 for 3 d. Half the plants were then analyzed for total Hg and MeHg. The remaining plants were transferred to mercury-free medium with low or high nutrient levels and posttreated for 3 days before analysis of total Hg and MeHg in order to measure MeHg formation in the absence of external Hg. The results indicate that nutrient level did not influence MeHg uptake, but that a high nutrient level reduced the distribution of MeHg to the shoots 2.7-fold versus low nutrient level. After treatment with HgCl2, MeHg was found in roots and new shoots but not in old shoots. The MeHg:total-Hg ratio was higher in new shoots than in roots, being 13 times higher at high versus low nutrient levels. Thus, MeHg formation was the same in new shoots independent of inorganic Hg concentration, since the total Hg level decreased at a high nutrient level.

  14. Water-Table Levels and Gradients, Nevada, 1947-2004

    USGS Publications Warehouse

    Lopes, Thomas J.; Buto, Susan G.; Smith, J. LaRue; Welborn, Toby L.

    2006-01-01

    In 1999, the U.S. Environmental Protection Agency began a program to protect the quality of ground water in areas other than ground-water protection areas. These other sensitive ground water areas (OSGWA) are areas that are not currently, but could eventually be, used as a source of drinking water. The OSGWA program specifically addresses existing wells that are used for underground injection of motor-vehicle waste. To help determine whether a well is in an OSGWA, the Nevada Division of Environmental Protection needs statewide information on depth to water and the water table, which partly control the susceptibility of ground water to contamination and contaminant transport. This report describes a study that used available maps and data to create statewide maps of water-table and depth-to-water contours and surfaces, assessed temporal changes in water-table levels, and characterized water-table gradients in selected areas of Nevada. A literature search of published water-table and depth-to-water contours produced maps of varying detail and scope in 104 reports published from 1948 to 2004. Where multiple maps covered the same area, criteria were used to select the most recent, detailed maps that covered the largest area and had plotted control points. These selection criteria resulted in water-table and depth-to-water contours that are based on data collected from 1947 to 2004 being selected from 39 reports. If not already available digitally, contours and control points were digitized from selected maps, entered into a geographic information system, and combined to make a statewide map of water-table contours. Water-table surfaces were made by using inverse distance weighting to estimate the water table between contours and then gridding the estimates. Depth-to-water surfaces were made by subtracting the water-table altitude from the land-surface altitude. Water-table and depth-to-water surfaces were made for only 21 percent of Nevada because of a lack of

  15. Analysis of water level variations in Brazilian basins using GRACE

    NASA Astrophysics Data System (ADS)

    Matos, A.; Blitzkow, D.; Almeida, F.; Costa, S.; Campos, I.; Barbosa, A.

    2012-01-01

    A comparison between daily in-situ water level time series measured at ground-based hydrometric stations (HS - 1,899 stations located in twelve Brazilian basins) of the Agência Nacional de Águas (ANA) with vertically-integrated water height anomaly deduced from the Gravity Recovery and Climate Experiment (GRACE) geoid is carried out in Brazil. The equivalent water height (EWH) of 10-day intervals of GRACE models were computed by GRGS/CNES. It is a 6-year analysis (July-2002 to May-2008). The coefficient of determination is computed between the ANA water level and GRACE EWH. Values higher than 0.6 were detected in the following basins: Amazon, north of Paraguay, Tocantins-Araguaia, Western North-East Atlantic and north of the Parnaíba. In the Uruguay (Pampas region) and the west of São Francisco basins, the coefficient of determination is around 0.5 and 0.6. These results were adjusted with a linear transfer function and two second degree polynomials (flood and ebb period) between GRACE EWH and ANA water level. The behavior of these two polynomials is related to the phase difference of the two time series and yielded four different types of responses. This paper shows seven ANA stations that represent these responses and relates them with their hydro-geological domain.

  16. Low-level measurements of tritium in water.

    PubMed

    Villa, M; Manjón, G

    2004-01-01

    Using a liquid scintillation counter, an experimental procedure for measuring low-level activity concentrations of tritium in environmental water has been developed by our laboratory, using the electrolytic tritium enrichment. Additionally, some quality tests were applied in order to assure the goodness of the method. Well-known water samples collected in the Tagus River (West of Spain) and the Danube River (Bulgaria), both affected by nuclear plant releases, were analysed and results were compared to previous data. The analytical procedure was applied to drinking water samples from the public water supply of Seville and mineral waters from different springs in Spain in order to characterize its origin. Due to the very low levels of tritium in the analysed samples, some results were reported as lower than the minimum detectable activity concentration (MDA). However, the count rate of these measurements was over the background count rate of LS counter in all the cases. For that reason, an exhaustive discussion about the meaning of the MDA, using an experimental essay, was made in order to establish a rigorous criterion that leads to a reliable value in the case of low-level measurements. PMID:15177365

  17. [Relationship between groundwater level in riparian wetlands and water level in the river].

    PubMed

    Xu, Hua-Shan; Zhao, Tong-Qian; Meng, Hong-Qi; Xu, Zong-Xue; Ma, Chao-Hong

    2011-02-01

    The development and degradation processes of riparian wetlands are significantly affected by river hydrological processes. By observing the variation of groundwater levels in riparian wetlands at the Kouma section of the Yellow River Wetland, especially that during the period of regulation for water and sediment at the Xiaolangdi Reservoir, relationship between groundwater level in riparian wetlands and flood water level in the river is studied. The results show that groundwater level in riparian wetlands is significantly affected by water level in the river investigated. There is a negative exponential relationship between groundwater level and the distance between wells and river. The correlation coefficient shows the maximum (R2 > 0.98) during the period of regulation for water and sediment. Affected by the cultivation system in the flooding area, distance between monitoring wells and river bank, water level in the river variation of groundwater level in the wetland changed greatly. In artificial wetland, which is far from the river, the inter-annual variation in groundwater levels show a " (see symbol)" shape, while in the farmland, which is close to the river, the inter-annual variation of groundwater levels show a big peak. The groundwater level 400 m from the river is affected by flood events obviously, that in the area which is less than 200 m from the river is significantly affected by flood events in the area which is especially less than that in the area that is less than 100 m from the river, the groundwater level is affected by flood events intensively. The result indicated that there was a very close relationship between groundwater and surface water, and it was the hydrological ecotone between groundwater of riparian wetlands and the river. It is very important that rational protection for this region (very important for the area which is less than 100 m from the river, important for the area that is between 100 m and 200 m from the river) is

  18. Water-level changes (1975-1998) in the Antelope Valley ground-water basin, California

    USGS Publications Warehouse

    Carlson, Carl S.; Phillips, Steven P.

    1998-01-01

    Antelope Valley is in the western part of the Mojave Desert in southern California, about 50 mi northeast of Los Angeles. Between 1975 and 1998, water levels in the valley have changed in response to a shift in ground-water use from agricultural to urban, declining in some areas and rising in others. A study to document these changes was conducted by the U.S. Geological Survey in cooperation with the Antelope Valley Water Group. This report presents the water-level data and the changes that occurred during this study period.

  19. Persistent photoconductivity in AlGaN/GaN heterojunction channels caused by the ionization of deep levels in the AlGaN barrier layer

    SciTech Connect

    Murayama, H.; Akiyama, Y.; Niwa, R.; Sakashita, H.; Sakaki, H.; Kachi, T.; Sugimoto, M.

    2013-12-04

    Time-dependent responses of drain current (I{sub d}) in an AlGaN/GaN HEMT under UV (3.3 eV) and red (2.0 eV) light illumination have been studied at 300 K and 250 K. UV illumination enhances I{sub d} by about 10 %, indicating that the density of two-dimensional electrons is raised by about 10{sup 12} cm{sup −2}. When UV light is turned off at 300 K, a part of increased I{sub d} decays quickly but the other part of increment is persistent, showing a slow decay. At 250 K, the majority of increment remains persistent. It is found that such a persistent increase of I{sub d} at 250 K can be partially erased by the illumination of red light. These photo-responses are explained by a simple band-bending model in which deep levels in the AlGaN barrier get positively charged by the UV light, resulting in a parabolic band bending in the AlGaN layer, while some potion of those deep levels are neutralized by the red light.

  20. CAN FLUORIDATION AFFECT WATER LEAD LEVELS AND LEAD NEUROTOXICITY?

    EPA Science Inventory

    Recent reports have attempted to show that certain approaches to fluoridating potable water is linked to increased levels of lead(II) in the blood. We examine these claims in light of the established science and critically evaluate their significance. The completeness of nexafluo...

  1. TRIHALOMETHANE LEVELS IN HOME TAP WATER AND SEMEN QUALITY

    EPA Science Inventory

    Trihalomethane Levels in Home Tap Water and Semen Quality
    Laura Fenster, 1 Kirsten Waller, 2 Gayle Windham, 1 Tanya Henneman, 2 Meredith Anderson, 2 Pauline Mendola, 3 James W. Overstreet, 4 Shanna H. Swan5

    1California Department of Health Services, Division of Environm...

  2. Comparison Between Water Level and Precipitation in Rio Negro Basin

    NASA Astrophysics Data System (ADS)

    Figliuolo, G. C.; Santos Da Silva, J.; Calmant, S.; Seyler, F.; Correia, F.; Oliveira, R. J.

    2013-12-01

    The Amazon Basin holds a lot of difficulties for providing data that enable regional researching works, because of its large extension and for having areas, whose access is very difficult. Remote sensing data presents an excellent way for monitoring the Amazon Basin and collecting data for researches. This current study aims matching radar altimetry data from the JASON-2, with the rainfall data from the TRMM satellite in order to analyze the relation between the water level and the precipitation in two different points along the Rio Negro Basin. After data analysis, it was possible noting a difference on the responding process for both regions. Whilst at the NEGRO_089_03 station (located in the city of São Gabriel da Cachoeira) the graphic of precipitation and water level were very similar, in NEGRO_063 station (located in the city of Manaus) the graphic showed a two month discrepancy due to the difference of the river's bottom size in both regions, at NEGRO_089_03's area for having a smaller river and the water level rises faster, whereas in NEGRO_063 the water level takes about two months to respond to precipitation.

  3. Individual Differences and Development in Water-Level Task Performance.

    ERIC Educational Resources Information Center

    Thomas, Hoben; Turner, Geoffrey, F. W.

    1991-01-01

    Presents research on individuals' ability to perform Piaget's water-level task. At almost every age and for each sex, some subjects had high probability of success and some had low. Age-related improvement was not a result of children's increasing accuracy in task performance. Differences in performance between sexes were evident at all ages.…

  4. Cellar-Associated Saccharomyces cerevisiae Population Structure Revealed High-Level Diversity and Perennial Persistence at Sauternes Wine Estates

    PubMed Central

    Börlin, Marine; Venet, Pauline; Claisse, Olivier; Salin, Franck

    2016-01-01

    ABSTRACT Three wine estates (designated A, B, and C) were sampled in Sauternes, a typical appellation of the Bordeaux wine area producing sweet white wine. From those wine estates, 551 yeast strains were collected between 2012 and 2014, added to 102 older strains from 1992 to 2011 from wine estate C. All the strains were analyzed through 15 microsatellite markers, resulting in 503 unique Saccharomyces cerevisiae genotypes, revealing high genetic diversity and a low presence of commercial yeast starters. Population analysis performed using Fst genetic distance or ancestry profiles revealed that the two closest wine estates, B and C, which have juxtaposed vineyard plots and common seasonal staff, share more related isolates with each other than with wine estate A, indicating exchange between estates. The characterization of isolates collected 23 years ago at wine estate C in relation to recent isolates obtained at wine estate B revealed the long-term persistence of isolates. Last, during the 2014 harvest period, a temporal succession of ancestral subpopulations related to the different batches associated with the selective picking of noble rotted grapes was highlighted. IMPORTANCE High genetic diversity of S. cerevisiae isolates from spontaneous fermentation on wine estates in the Sauternes appellation of Bordeaux was revealed. Only 7% of all Sauternes strains were considered genetically related to specific commercial strains. The long-term persistence (over 20 years) of S. cerevisiae profiles on a given wine estate is highlighted. PMID:26969698

  5. Estimating persistence of brominated and chlorinated organic pollutants in air, water, soil, and sediments with the QSPR-based classification scheme.

    PubMed

    Puzyn, T; Haranczyk, M; Suzuki, N; Sakurai, T

    2011-02-01

    We have estimated degradation half-lives of both brominated and chlorinated dibenzo-p-dioxins (PBDDs and PCDDs), furans (PBDFs and PCDFs), biphenyls (PBBs and PCBs), naphthalenes (PBNs and PCNs), diphenyl ethers (PBDEs and PCDEs) as well as selected unsubstituted polycyclic aromatic hydrocarbons (PAHs) in air, surface water, surface soil, and sediments (in total of 1,431 compounds in four compartments). Next, we compared the persistence between chloro- (relatively well-studied) and bromo- (less studied) analogs. The predictions have been performed based on the quantitative structure-property relationship (QSPR) scheme with use of k-nearest neighbors (kNN) classifier and the semi-quantitative system of persistence classes. The classification models utilized principal components derived from the principal component analysis of a set of 24 constitutional and quantum mechanical descriptors as input variables. Accuracies of classification (based on an external validation) were 86, 85, 87, and 75% for air, surface water, surface soil, and sediments, respectively. The persistence of all chlorinated species increased with increasing halogenation degree. In the case of brominated organic pollutants (Br-OPs), the trend was the same for air and sediments. However, we noticed that the opposite trend for persistence in surface water and soil. The results suggest that, due to high photoreactivity of C-Br chemical bonds, photolytic processes occurring in surface water and soil are able to play significant role in transforming and removing Br-OPs from these compartments. This contribution is the first attempt of classifying together Br-OPs and Cl-OPs according to their persistence, in particular, environmental compartments. PMID:20386980

  6. The occurrence of persistent chlorinated and brominated organic contaminants in the European eel (Anguilla anguilla) in Irish waters.

    PubMed

    McHugh, Brendan; Poole, Russell; Corcoran, John; Anninou, Pinelopi; Boyle, Brian; Joyce, Eileen; Barry Foley, M; McGovern, Evin

    2010-04-01

    The European eel (Anguilla anguilla) is a relatively high lipid, long lived species capable of living in a variety of brackish, fresh and marine habitats. As such, eels can accumulate organic pollutants and have been incorporated into environmental monitoring programs as a suitable "bioindicator" species for the determination of the levels of organic contaminants within different water bodies. The global eel stock is now in decline and while the cause of the collapse remains unidentified, it is likely to include a combination of anthropogenic mortality in addition to environmental degradation. This study provides valuable data on a range of contaminants (PCDD/Fs, PCBs, OCPs, PBDEs, HBCD, TBBPA and PBBs) and extractable lipid levels in eel muscle tissue collected from five Irish catchments. Extractable lipid levels were lower in the yellow eels compared to those in the silver eels. These levels were similar to those reported elsewhere and it has been posited that a decline in the lipid content in yellow eels may have consequences for the future viability of the stock. With the exception of higher substituted dioxins (especially OCDD), in three samples collected from one catchment (Burrishoole) in the West of Ireland, POP levels in general were determined to be low in eels from Irish waters compared to those in other countries. PMID:20153504

  7. A high resolution water level forecast for the German Bight

    NASA Astrophysics Data System (ADS)

    Niehüser, Sebastian; Dangendorf, Sönke; Arns, Arne; Jensen, Jürgen

    2016-04-01

    Many coastal regions worldwide are potentially endangered by storm surges which can cause disastrous damages and loss of life. Due to climate change induced sea level rise, an accumulation of such events is expected by the end of the 21th century. Therefore, advanced storm surge warnings are needed to be prepared when another storm surge hits the coast. In the shallow southeastern North Sea these storm surge warnings are nowadays routinely provided for selected tide gauge locations along a coastline through state-of-the-art forecast systems, which are based on a coupled system of empirical tidal predictions and numerical storm surge forecasts. Along the German North Sea coastline, the Federal Maritime and Hydrographic Agency in cooperation with the German Weather Service is responsible for the storm surge warnings. They provide accurate, high frequency and real-time water level forecasts for up to six days ahead at selected tide gauge sites via internet, telephone and broadcast. Since water levels along the German North Sea coastline are dominated by shallow water effects and a very complex bathymetric structure of the seabed, the pointwise forecast is not necessarily transferable to un-gauged areas between the tide gauges. Here we aim to close this existing gap and develop water level forecasts with a high spatial (continuously with a resolution of at least 1 kilometer) as well as a high temporal (at least 15-minute values) resolution along the entire German North Sea coastline. We introduce a new methodology for water level forecasts which combines empirical or statistical and numerical models. While the tidal forecast is performed by non-parametric interpolation techniques between un-gauged and gauged sites, storm surges are estimated on the basis of statistical/empirical storm surge formulas taken from a numerical model hindcast. The procedure will be implemented in the operational mode forced with numerical weather forecasts.

  8. Recognition and knowledge of the water-level principle.

    PubMed

    Howard, I P

    1978-01-01

    Piaget and Inhelder showed that children do not realize that the surface of a fluid remains horizontal in a tilted vessel. Several studies have since shown that many adults do not have an adequate concept of the water-level principle. However, in all these studies, drawings of vessels, or other abstract displays, were used. The present experiment is an investigation of whether adults who do not know the water-level principle are able to recognize the correct orientation of a fluid surface in realistic three-dimensional scenes and in cinematographic sequences. It was found that all subjects who could state the principle clearly, could precisely and accurately recognize the correct fluid level. More than half the subjects did not know the principle and all these subjects showed evidence in their judgments of only the crudest perceptual schema. PMID:652472

  9. Water-level changes induced by local and distant earthquakes at Long Valley caldera, California

    NASA Astrophysics Data System (ADS)

    Roeloffs, Evelyn; Sneed, Michelle; Galloway, Devin L.; Sorey, Michael L.; Farrar, Christopher D.; Howle, James F.; Hughes, Jennifer

    2003-10-01

    Distant as well as local earthquakes have induced groundwater-level changes persisting for days to weeks at Long Valley caldera, California. Four wells open to formations as deep as 300 m have responded to 16 earthquakes, and responses to two earthquakes in the 3-km-deep Long Valley Exploratory Well (LVEW) show that these changes are not limited to weathered or unconsolidated near-surface rocks. All five wells exhibit water-level variations in response to earth tides, indicating they can be used as low-resolution strainmeters. Earthquakes induce gradual water-level changes that increase in amplitude for as long as 30 days, then return more slowly to pre-earthquake levels. The gradual water-level changes are always drops at wells LKT, LVEW, and CH-10B, and always rises at well CW-3. At a dilatometer just outside the caldera, earthquake-induced strain responses consist of either a step followed by a contractional strain-rate increase, or a transient contractional signal that reaches a maximum in about seven days and then returns toward the pre-earthquake value. The sizes of the gradual water-level changes generally increase with earthquake magnitude and decrease with hypocentral distance. Local earthquakes in Long Valley produce coseismic water-level steps; otherwise the responses to local earthquakes and distant earthquakes are indistinguishable. In particular, water-level and strain changes in Long Valley following the 1992 M7.3 Landers earthquake, 450 km distant, closely resemble those initiated by a M4.9 local earthquake on November 22, 1997, during a seismic swarm with features indicative of fluid involvement. At the LKT well, many of the response time histories are identical for 20 days after each earthquake, and can be matched by a theoretical solution giving the pore pressure as a function of time due to diffusion of a nearby, instantaneous, pressure drop. Such pressure drops could be produced by accelerated inflation of the resurgent dome by amounts too

  10. Water-level changes induced by local and distant earthquakes at Long Valley caldera, California

    USGS Publications Warehouse

    Roeloffs, E.; Sneed, M.; Galloway, D.L.; Sorey, M.L.; Farrar, C.D.; Howle, J.F.; Hughes, J.

    2003-01-01

    Distant as well as local earthquakes have induced groundwater-level changes persisting for days to weeks at Long Valley caldera, California. Four wells open to formations as deep as 300 m have responded to 16 earthquakes, and responses to two earthquakes in the 3-km-deep Long Valley Exploratory Well (LVEW) show that these changes are not limited to weathered or unconsolidated near-surface rocks. All five wells exhibit water-level variations in response to earth tides, indicating they can be used as low-resolution strainmeters. Earthquakes induce gradual water-level changes that increase in amplitude for as long as 30 days, then return more slowly to pre-earthquake levels. The gradual water-level changes are always drops at wells LKT, LVEW, and CH-10B, and always rises at well CW-3. At a dilatometer just outside the caldera, earthquake-induced strain responses consist of either a step followed by a contractional strain-rate increase, or a transient contractional signal that reaches a maximum in about seven days and then returns toward the pre-earthquake value. The sizes of the gradual water-level changes generally increase with earthquake magnitude and decrease with hypocentral distance. Local earthquakes in Long Valley produce coseismic water-level steps; otherwise the responses to local earthquakes and distant earthquakes are indistinguishable. In particular, water-level and strain changes in Long Valley following the 1992 M7.3 Landers earthquake, 450 km distant, closely resemble those initiated by a M4.9 local earthquake on November 22, 1997, during a seismic swarm with features indicative of fluid involvement. At the LKT well, many of the response time histories are identical for 20 days after each earthquake, and can be matched by a theoretical solution giving the pore pressure as a function of time due to diffusion of a nearby, instantaneous, pressure drop. Such pressure drops could be produced by accelerated inflation of the resurgent dome by amounts too

  11. Human Cytomegalovirus Persistence

    PubMed Central

    Goodrum, Felicia; Caviness, Katie; Zagallo, Patricia

    2012-01-01

    Summary Viral persistence is the rule following infection with all herpesviruses. The β-herpesvirus, human cytomegalovirus (HCMV), persists through chronic and latent states of infection. Both the chronic and latent states of infection contribute to HCMV persistence and to the high HCMV seroprevalence worldwide. The chronic infection is poorly defined molecularly, but clinically manifests as low-level virus shedding over extended periods of time and often in the absence of symptoms. Latency requires long-term maintenance of viral genomes in a reversibly quiescent state in the immunocompetent host. In this review, we focus on recent advances in the biology of HCMV persistence, particularly with respect to the latent mode of persistence. Latently infected individuals harbor HCMV genomes in hematopoietic cells and maintain large subsets of HCMV-specific T-cells. In the last few years, impressive advances have been made in understanding virus-host interactions important to HCMV infection, many of which will profoundly impact latency and persistence. We discuss these advances and their known or potential impact on viral latency. As herpesviruses are met with similar challenges in achieving latency and often employ conserved strategies to persist, we discuss current and future directions of HCMV persistence in the context of the greater body of knowledge regarding α-and γ-herpesviruses persistence. PMID:22329758

  12. A new water level gauge for cold region application

    SciTech Connect

    Shih, H.H.; Moss, M.K.; Dixon, J.C.

    1995-12-31

    The traditional gas purging (bubbler) water level gauge has been widely sued because of its simplicity, ruggedness and ability to operate in areas of ice cover. However, its mechanically-based sensing and recording system and the need for density information to compute water level have caused inconveniences in field operations. This paper describes a new design that records and telemeters digital data and allows computation of water density directly from the pressure measurements. Major measurement error sources are also identified and quantified. The performance in water level measurement is comparable to the National Ocean Service`s standard air acoustic tide gauge. Deriving density from pressure measurements obviates the need for use of a separate conductivity/temperature/depth instrument, which can be prone to fouling. The uncertainty in density determination is less than 0.0005 g/cc in laboratory tests; in the field, it varies from 0.0015 g/cc under low wave conditions to 0.003 g/cc for high wave conditions. The instrument has been successfully deployed at several cold region sites including the Arctic and Antarctic regions.

  13. How Temperature and Water levels affect Polar Mesospheric Cloud Formation

    NASA Astrophysics Data System (ADS)

    Smith, L. L.; Randall, C. E.; Harvey, V.

    2012-12-01

    Using the Cloud Imaging and Particle Size (CIPS) instrument data, which is part of the Aeronomy in the Mesosphere (AIM) mission, we compare the albedo and ice water content measurements of CIPS with the Navy Operation Global Atmospheric Prediction System - Advanced Level Phyiscs and High Altitude (NOGAPS-ALPHA) temperature and water vapor data in order to derive a greater understanding of cloud formation and physics. We particularly focus on data from June 2007 and July 2007 in this case study because of particular cloud structures and formations during this time period for future studies.

  14. Persistence of F-Specific RNA Coliphages in Surface Waters from a Produce Production Region along the Central Coast of California

    PubMed Central

    Ravva, Subbarao V.; Sarreal, Chester Z.

    2016-01-01

    F+ RNA coliphages (FRNA) are used to source-track fecal contamination and as surrogates for enteric pathogen persistence in the environment. However, the environmental persistence of FRNA is not clearly understood and necessitates the evaluation of the survival of prototype and environmental isolates of FRNA representing all four genogroups in surface waters from the central coast of California. Water temperature played a significant role in persistence–all prototype and environmental strains survived significantly longer at 10°C compared to 25°C. Similarly, the availability of host bacterium was found to be critical in FRNA survival. In the absence of E. coli Famp, all prototypes of FRNA disappeared rapidly with a D-value (days for one log reduction) of <1.2 d from water samples incubated at 25°C; the longest surviving prototype was SP. However, in the presence of the host, the order of persistence at 25°C was QB>MS2>SP>GA and at 10°C it was QB = MS2>GA>SP. Significant differences in survival were observed between prototypes and environmental isolates of FRNA. While most environmental isolates disappeared rapidly at 25°C and in the absence of the host, members of genogroups GIII and GI persisted longer with the host compared to members of GII and GIV. Consequentially, FRNA based source tracking methods can be used to detect phages from recent fecal contamination along with those that persist longer in the environment as a result of cooler temperatures and increased host presence. PMID:26784030

  15. Comparison of nitrate levels in raw water and finished water from historical monitoring data on Iowa municipal drinking water supplies.

    PubMed

    Weyer, Peter J; Smith, Brian J; Feng, Zhen-Fang; Kantamneni, Jiji R; Riley, David G

    2006-05-01

    Nitrate contamination of water sources is a concern where large amounts of nitrogen fertilizers are regularly applied to soils. Ingested nitrate from dietary sources and drinking water can be converted to nitrite and ultimately to N-nitroso compounds, many of which are known carcinogens. Epidemiologic studies of drinking water nitrate and cancer report mixed findings; a criticism is the use of nitrate concentrations from retrospective drinking water data to assign exposure levels. Residential point-of-use nitrate data are scarce; gaps in historical data for municipal supply finished water hamper exposure classification efforts. We used generalized linear regression models to estimate and compare historical raw water and finished water nitrate levels (1960s-1990s) in single source Iowa municipal supplies to determine whether raw water monitoring data could supplement finished water data to improve exposure assessment. Comparison of raw water and finished water samples (same sampling date) showed a significant difference in nitrate levels in municipalities using rivers; municipalities using other surface water or alluvial groundwater had no difference in nitrate levels. A regional aggregation of alluvial groundwater municipalities was constructed based on results from a previous study showing regional differences in nitrate contamination of private wells; results from this analysis were mixed, dependent upon region and decade. These analyses demonstrate using historical raw water nitrate monitoring data to supplement finished water data for exposure assessment is appropriate for individual Iowa municipal supplies using alluvial groundwater, lakes or reservoirs. Using alluvial raw water data on a regional basis is dependent on region and decade.

  16. Methods of measuring water levels in deep wells

    USGS Publications Warehouse

    Garber, M.S.; Koopman, F. C.

    1968-01-01

    Accurate measurement of water levels deeper than 1,000 feet in wells requires specialized equipment. Corrections for stretch and thermal expansion of measuring tapes must be considered, and other measuring devices must be calibrated periodically. Bore-hole deviation corrections also must be made. Devices for recording fluctuation of fluid level usually require mechanical modification for use at these depths. A multichannel recording device utilizing pressure transducers has been constructed. This device was originally designed to record aquifer response to nearby underground nuclear explosions but can also be used for recording data from multi-well pumping tests. Bottom-hole recording devices designed for oil-field use have been utilized in a limited manner. These devices were generally found to lack the precision required, in ground-water investigations at the Nevada Test Site but may be applicable in other areas. A newly developed bottom-hole recording pressure gauge of improved accuracy has been used with satisfactory results.

  17. Traditional and Host-Associated Fecal Indicator Bacterial Patterns in Southern California Watersheds: Field Source Identification Studies and Laboratory Microcosms Investigating Presence and Persistence in Water and Sediments

    NASA Astrophysics Data System (ADS)

    Mika, Kathryn Beth

    Overall, recreational beach water quality remains an issue of concern in Southern California and across the globe. Many factors come into play when determining water quality, including physical issues such as the myriad sources that contribute pollution to the site and financial and political issues that control the way water quality is monitored and determined. Current national regulations require the monitoring of fecal indicator bacteria in order to determine recreational water quality. However, it is also important to identify biological and geographical sources of pollution to consistently impaired locations. A commonly applied approach to meet the goals of source identification is to sample sites that have been high in FIB for further study. A tiered approach such as this, however, assumes a correlation between FIB and the sources of interest in the watershed. The research described in this dissertation tests this assumption in two Southern California watersheds, Santa Monica Canyon and Ventura Harbor. In both cases, a tiered approach to sampling using FIB as a first tier to guide sampling would have failed to identify sources of human fecal pollution (as identified by the presence of the human-associated Bacteroides marker HF183). Every watershed is a distinct environment that has different potential sources of bacteria and many factors contributing to the persistence of the bacteria. Rather than attempting to apply an indicator that has worked as a first tier in other watersheds, it would be better to have as a first tier an in-depth study of the watershed using historical data or local experts to provide information on the most likely sources of pollution in the watershed. Using this information it would be possible to design a study using FIB and one or more source-associated parameters to identify specific sources of pollution in the watershed. In addition, sampling FIB and other parameters such as HF183 allow the application of other

  18. Projecting Future Water Levels of the Laurentian Great Lakes

    NASA Astrophysics Data System (ADS)

    Bennington, V.; Notaro, M.; Holman, K.

    2013-12-01

    The Laurentian Great Lakes are the largest freshwater system on Earth, containing 84% of North America's freshwater. The lakes are a valuable economic and recreational resource, valued at over 62 billion in annual wages and supporting a 7 billion fishery. Shipping, recreation, and coastal property values are significantly impacted by water level variability, with large economic consequences. Great Lakes water levels fluctuate both seasonally and long-term, responding to natural and anthropogenic climate changes. Due to the integrated nature of water levels, a prolonged small change in any one of the net basin supply components: over-lake precipitation, watershed runoff, or evaporation from the lake surface, may result in important trends in water levels. We utilize the Abdus Salam International Centre for Theoretical Physics's Regional Climate Model Version 4.5.6 to dynamically downscale three global global climate models that represent a spread of potential future climate change for the region to determine whether the climate models suggest a robust response of the Laurentian Great Lakes to anthropogenic climate change. The Model for Interdisciplinary Research on Climate Version 5 (MIROC5), the National Centre for Meteorological Research Earth system model (CNRM-CM5), and the Community Climate System Model Version 4 (CCSM4) project different regional temperature increases and precipitation change over the next century and are used as lateral boundary conditions. We simulate the historical (1980-2000) and late-century periods (2080-2100). Upon model evaluation we will present dynamically downscaled projections of net basin supply changes for each of the Laurentian Great Lakes.

  19. Persistent organic pollutants in marine fish from Yongxing Island, South China Sea: levels, composition profiles and human dietary exposure assessment.

    PubMed

    Sun, Yu-Xin; Hao, Qing; Xu, Xiang-Rong; Luo, Xiao-Jun; Wang, Shuai-Long; Zhang, Zai-Wang; Mai, Bi-Xian

    2014-03-01

    Little data is available on the bioaccumulation of persistent organic pollutants (POPs) in marine organisms from South China Sea (SCS). Five marine fish species were collected from Yongxing Island, SCS to investigate the presence of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs). PBDEs, PCBs, and DDTs concentrations ranged from 2.0-117, 6.3-199, and 9.7-5831 ng g(-1) lw, respectively. In general, contaminants measured in this study were at the lower end of the global range. Concentrations of PBDEs and PCBs were significantly correlated in fish samples, implying that PBDEs are as prevalent as PCBs in Yongxing Island. Among the five fish species studied, yellow striped goatfish had the highest concentrations of PBDEs, PCBs, and DDTs, probably attributed to its different living and feeding habits. The contaminant distribution pattern indicated that agrochemical source is more important than industrial source in Yongxing Island, SCS. The average estimated daily intakes of PBDEs, PCBs, and DDTs via fish consumption by local residents in the coastal areas of South China ranged from 1.42-5.91, 3.20-13.3, and 8.08-33.6 ng d(-1), which were lower than those in previous studies, suggesting that consumption of marine fish in Yongxing Island, SCS, might not subject local residents to significant health risk as far as POPs are concerned. This is the first study to report the occurrence of POPs in marine biota from SCS.

  20. Can mercury in fish be reduced by water level management? Evaluating the effects of water level fluctuation on mercury accumulation in yellow perch (Perca flavescens)

    USGS Publications Warehouse

    Larson, James H.; Maki, Ryan P.; Knights, Brent C.; Gray, Brian R.

    2014-01-01

    Mercury (Hg) contamination of fisheries is a major concern for resource managers of many temperate lakes. Anthropogenic Hg contamination is largely derived from atmospheric deposition within a lake’s watershed, but its incorporation into the food web is facilitated by bacterial activity in sediments. Temporal variation in Hg content of fish (young-of-year yellow perch) in the regulated lakes of the Rainy–Namakan complex (on the border of the United States and Canada) has been linked to water level (WL) fluctuations, presumably through variation in sediment inundation. As a result, Hg contamination of fish has been linked to international regulations of WL fluctuation. Here we assess the relationship between WL fluctuations and fish Hg content using a 10-year dataset covering six lakes. Within-year WL rise did not appear in strongly supported models of fish Hg, but year-to-year variation in maximum water levels (∆maxWL) was positively associated with fish Hg content. This WL effect varied in magnitude among lakes: In Crane Lake, a 1 m increase in ∆maxWL from the previous year was associated with a 108 ng increase in fish Hg content (per gram wet weight), while the same WL change in Kabetogama was associated with only a 5 ng increase in fish Hg content. In half the lakes sampled here, effect sizes could not be distinguished from zero. Given the persistent and wide-ranging extent of Hg contamination and the large number of regulated waterways, future research is needed to identify the conditions in which WL fluctuations influence fish Hg content.

  1. Water Resources Data, Georgia, 2002--Volume 1: Continuous water-level, streamflow, water-quality data, and periodic water-quality data, Water Year 2002

    USGS Publications Warehouse

    Hickey, Andrew C.; Kerestes, John F.; McCallum, Brian E.

    2002-01-01

    Water resources data for the 2002 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in two volumes in a digital format on a CD-ROM. Volume one of this report contains water resources data for Georgia collected during water year 2002, including: discharge records of 154 gaging stations; stage for 165 gaging stations; precipitation for 105 gaging stations; information for 20 lakes and reservoirs; continuous water-quality records for 27 stations; the annual peak stage and annual peak discharge for 72 crest-stage partial-record stations; and miscellaneous streamflow measurements at 50 stations, and miscellaneous water-quality data recorded by the NAWQA program in Georgia. Volume two of this report contains water resources data for Georgia collected during calendar year 2002, including continuous water-level records of 155 ground-water wells and periodic records at 132 water-quality stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia.

  2. Water Resources Data, Georgia, 2003, Volume 1: Continuous water-level, streamflow, water-quality data, and periodic water-quality data, Water Year 2003

    USGS Publications Warehouse

    Hickey, Andrew C.; Kerestes, John F.; McCallum, Brian E.

    2004-01-01

    Water resources data for the 2003 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in two volumes in a digital format on a CD-ROM. Volume one of this report contains water resources data for Georgia collected during water year 2003, including: discharge records of 163 gaging stations; stage for 187 gaging stations; precipitation for 140 gaging stations; information for 19 lakes and reservoirs; continuous water-quality records for 40 stations; the annual peak stage and annual peak discharge for 65 crest-stage partial-record stations; and miscellaneous streamflow measurements at 36 stations, and miscellaneous water-quality data at 162 stations in Georgia. Volume two of this report contains water resources data for Georgia collected during calendar year 2003, including continuous water-level records of 156 ground-water wells and periodic records at 130 water-quality stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia.

  3. Persistent low levels of serum hCG due to heterophilic mouse antibodies: an unrecognized pitfall in the diagnosis of trophoblastic disease.

    PubMed

    González Aguilera, B; Syrios, P; Gadisseur, R; Luyckx, F; Cavalier, E; Beckers, A; Valdes-Socin, H

    2016-06-01

    Phantom hCG refers to persistent mild elevations of hCG, leading physicians to unnecessary treatments whereas neither a true hCG nor a trophoblastic disease is present. We report the case of a 23-year-old woman with persistent low levels of serum hCG detected one month after miscarriage. As choriocarcinoma was suspected, a chemotherapy trial of methotrexate was prescribed, without any hCG reduction. Subsequently, laparoscopy ruled out a trophoblastic residue and the patient was referred to the Endocrine Unit for further investigations. While low levels of hCG were still detected in serum, no hCG was detected in the urine. In addition, when serum was processed in a HBT tube for revealing heterophilic antibodies, hCG was no longer detected. Such finding indicated the presence of phantom hCG due to heterophilic mouse antibodies interaction. This case raises the need of clinico-biological discussion to avoid inappropriate therapeutic decisions. Based on this case experience and after review of the literature, we suggest that current gynecological protocols for the diagnosis and treatment of trophoblastic disease should consider the inclusion of urinary hCG and/or a test for serum heterophilic antibodies when appropriate. PMID:26792068

  4. Persistent low levels of serum hCG due to heterophilic mouse antibodies: an unrecognized pitfall in the diagnosis of trophoblastic disease.

    PubMed

    González Aguilera, B; Syrios, P; Gadisseur, R; Luyckx, F; Cavalier, E; Beckers, A; Valdes-Socin, H

    2016-06-01

    Phantom hCG refers to persistent mild elevations of hCG, leading physicians to unnecessary treatments whereas neither a true hCG nor a trophoblastic disease is present. We report the case of a 23-year-old woman with persistent low levels of serum hCG detected one month after miscarriage. As choriocarcinoma was suspected, a chemotherapy trial of methotrexate was prescribed, without any hCG reduction. Subsequently, laparoscopy ruled out a trophoblastic residue and the patient was referred to the Endocrine Unit for further investigations. While low levels of hCG were still detected in serum, no hCG was detected in the urine. In addition, when serum was processed in a HBT tube for revealing heterophilic antibodies, hCG was no longer detected. Such finding indicated the presence of phantom hCG due to heterophilic mouse antibodies interaction. This case raises the need of clinico-biological discussion to avoid inappropriate therapeutic decisions. Based on this case experience and after review of the literature, we suggest that current gynecological protocols for the diagnosis and treatment of trophoblastic disease should consider the inclusion of urinary hCG and/or a test for serum heterophilic antibodies when appropriate.

  5. Shoot Injury Increases the Level of Persistence of Salmonella enterica Serovar Sofia and Listeria innocua on Cos Lettuce and of Salmonella enterica Serovar Sofia on Chive.

    PubMed

    Harapas, Dean; Premier, Robert; Tomkins, Bruce; Hepworth, Graham; Ajlouni, Said

    2015-12-01

    Minor shoot injury significantly (P < 0.05) increased the level at which Salmonella enterica serovar Sofia persisted on cos lettuce in the greenhouse. Initial mean counts of the Salmonella on the injured and uninjured cos lettuce were on the order of 6 log CFU/g. After 3 days, the mean count decreased to 4.8 log CFU/g on the injured plants compared with the significantly (P < 0.05) smaller count of 3.4 log CFU/g on the uninjured plants. By the end of the 3-week experiment, the count from the injured plants was 2.9 log CFU/g compared with a count of below the level of detection from the uninjured plants. A similar pattern of bacterial persistence was observed on injured versus uninjured plants by using Listeria innocua on cos lettuce and S. enterica serovar Sofia on chive. The findings reaffirm earlier results with Escherichia coli and increase the impetus to avoid shoot injury during the production of cos lettuce and chive, if bacteria of food safety concern are present.

  6. Screening Experiments for Removal of Low-Level Tritiated Water

    SciTech Connect

    Kim, Yun Mi; Baney, Ronald; Powers, Kevin; Koopman, Ben; Tulenko, James

    2005-03-15

    Screening experiments for low levels of tritiated water (HTO) remediation based upon selective adsorption/desorption mechanisms utilizing equilibrium isotope effects have been carried out. Several organic and inorganic high surface area materials were investigated to assess their ability to selectively adsorb low concentrations of HTO. Ion-exchange resins with cation functionalities, chitosan, sodium alginate, and several inorganic media modified with metal cations exhibited promising results. Biomaterials, for example, chitosan and modified alginate, demonstrated positive results. Based on the literature and our preliminary testing, we postulate four possible mechanisms for selected tritium adsorption: hydrogen ion exchange, HTO coordination with surface cation sites, hydrogen bonding to surface basic sites, and secondary hydrogen bonding (structural water) in fine pores.

  7. Considering rating curve uncertainty in water level predictions

    NASA Astrophysics Data System (ADS)

    Sikorska, A. E.; Scheidegger, A.; Banasik, K.; Rieckermann, J.

    2013-11-01

    Streamflow cannot be measured directly and is typically derived with a rating curve model. Unfortunately, this causes uncertainties in the streamflow data and also influences the calibration of rainfall-runoff models if they are conditioned on such data. However, it is currently unknown to what extent these uncertainties propagate to rainfall-runoff predictions. This study therefore presents a quantitative approach to rigorously consider the impact of the rating curve on the prediction uncertainty of water levels. The uncertainty analysis is performed within a formal Bayesian framework and the contributions of rating curve versus rainfall-runoff model parameters to the total predictive uncertainty are addressed. A major benefit of the approach is its independence from the applied rainfall-runoff model and rating curve. In addition, it only requires already existing hydrometric data. The approach was successfully demonstrated on a small catchment in Poland, where a dedicated monitoring campaign was performed in 2011. The results of our case study indicate that the uncertainty in calibration data derived by the rating curve method may be of the same relevance as rainfall-runoff model parameters themselves. A conceptual limitation of the approach presented is that it is limited to water level predictions. Nevertheless, regarding flood level predictions, the Bayesian framework seems very promising because it (i) enables the modeler to incorporate informal knowledge from easily accessible information and (ii) better assesses the individual error contributions. Especially the latter is important to improve the predictive capability of hydrological models.

  8. Considering rating curve uncertainty in water level predictions

    NASA Astrophysics Data System (ADS)

    Sikorska, A. E.; Scheidegger, A.; Banasik, K.; Rieckermann, J.

    2013-03-01

    Streamflow cannot be measured directly and is typically derived with a rating curve model. Unfortunately, this causes uncertainties in the streamflow data and also influences the calibration of rainfall-runoff models if they are conditioned on such data. However, it is currently unknown to what extent these uncertainties propagate to rainfall-runoff predictions. This study therefore presents a quantitative approach to rigorously consider the impact of the rating curve on the prediction uncertainty of water levels. The uncertainty analysis is performed within a formal Bayesian framework and the contributions of rating curve versus rainfall-runoff model parameters to the total predictive uncertainty are addressed. A major benefit of the approach is its independence from the applied rainfall-runoff model and rating curve. In addition, it only requires already existing hydrometric data. The approach was successfully tested on a small urbanized basin in Poland, where a dedicated monitoring campaign was performed in 2011. The results of our case study indicate that the uncertainty in calibration data derived by the rating curve method may be of the same relevance as rainfall-runoff model parameters themselves. A conceptual limitation of the approach presented is that it is limited to water level predictions. Nevertheless, regarding flood level predictions, the Bayesian framework seems very promising because it (i) enables the modeler to incorporate informal knowledge from easily accessible information and (ii) better assesses the individual error contributions. Especially the latter is important to improve the predictive capability of hydrological models.

  9. Glyphosate persistence in seawater.

    PubMed

    Mercurio, Philip; Flores, Florita; Mueller, Jochen F; Carter, Steve; Negri, Andrew P

    2014-08-30

    Glyphosate is one of the most widely applied herbicides globally but its persistence in seawater has not been reported. Here we quantify the biodegradation of glyphosate using standard "simulation" flask tests with native bacterial populations and coastal seawater from the Great Barrier Reef. The half-life for glyphosate at 25 °C in low-light was 47 days, extending to 267 days in the dark at 25 °C and 315 days in the dark at 31 °C, which is the longest persistence reported for this herbicide. AMPA, the microbial transformation product of glyphosate, was detected under all conditions, confirming that degradation was mediated by the native microbial community. This study demonstrates glyphosate is moderately persistent in the marine water under low light conditions and is highly persistent in the dark. Little degradation would be expected during flood plumes in the tropics, which could potentially deliver dissolved and sediment-bound glyphosate far from shore.

  10. Levels and temporal trends (1983-2003) of persistent organic pollutants (POPs) and mercury (Hg) in seabird eggs from Northern Norway.

    PubMed

    Helgason, Lisa B; Barrett, Rob; Lie, Elisabeth; Polder, Anuschka; Skaare, Janneche U; Gabrielsen, Geir W

    2008-09-01

    The main objective of this study was to investigate possible temporal trends of persistent organic pollutants (POPs) and mercury in eggs of herring gulls (Larus argentatus), black-legged kittiwakes (Rissa tridactyla), common guillemots (Uria aalge) and Atlantic puffins (Fratercula arctica) in Northern Norway. Eggs were collected in 1983, 1993 and 2003. Egg concentrations of POPs (PCB congeners IUPAC numbers: CB-28, 74, 66, 101, 99, 110, 149, 118, 153, 105, 141, 138, 187, 128, 156, 157, 180, 170, 194, 206, HCB, alpha-HCH, beta-HCH, gamma-HCH, oxychlordane, trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT and p,p'-DDT) and mercury were quantified. Generally, POP levels decreased between 1983 and 2003 in all species. No significant temporal trend in mercury levels was found between 1983 and 2003. PMID:18262696

  11. Effects of persistent selective suppression of ganglionic butyrylcholinesterase on steady state and regenerating levels of acetylcholinesterase: implications regarding function of butyrylcholinesterase and regulation of protein synthesis.

    PubMed Central

    Koelle, W A; Koelle, G B; Smyrl, E G

    1976-01-01

    Persistent selective suppression of the butyrylcholinesterase (cholinesterase; acylcholine acyl-hydrolase, EC 3.1.1.8) activity of the superior cervical, stellate, and ciliary ganglia of cats by the daily administration of tetramonoisopropyl pyrophosphortetramide, 3.0 mumol/kg, intravenously, for 6 days produced a significant elevation in the levels of ganglionic acetylcholinesterase (acetylcholine hydrolase, EC 3.1.1.7). When the same procedure was preceded by the inactivation of over 95% of the ganglionic acetylcholinesterase by sarin, 2.0 mumol/kg, intravenously, the rate of regeneration of acetylcholinesterase was decreased. Results are interpreted as evidence that ganglionic butyrylcholinesterase may serve as a precursor to acetylcholinesterase, and that the level of butyrylcholinesterase may regulate the rate of acetylcholinesterase synthesis. PMID:1066704

  12. [Residual levels of acetochlor in source water and drinking water of China's major cities].

    PubMed

    Yu, Zhi-Yong; Jin, Fen; Li, Hong-Yan; An, Wei; Yang, Min

    2014-05-01

    The concentration levels of acetochlor were investigated in source water and drinking water from 36 major cities in China by solid phase extraction (SPE) combined with gas chromatography - mass spectrometry (GC-MS). Acetochlor detection rate was 66.9% in all the 145 source water samples collected with an average concentration of 33.9 ng L-1. The average removal rate of acetochlor was limited through the drinking water treatment process. The detection concentration of the northeast region was the highest. The concentrations of acetochlor detected in lake were higher than those in river and groundwater as source water. The detection rate and concentration of Liaohe river watershed and the coastal watershed were the highest.

  13. Processing of water level derived from water pressure data at the Time Series Station Spiekeroog

    NASA Astrophysics Data System (ADS)

    Holinde, L.; Badewien, T. H.; Freund, J. A.; Stanev, E. V.; Zielinski, O.

    2015-04-01

    The quality of water level time series data strongly varies with periods of high and low quality sensor data. In this paper we are presenting the processing steps which were used to generate high quality water level data from water pressure measured at the Time Series Station (TSS) Spiekeroog. The TSS is positioned in a tidal inlet between the islands of Spiekeroog and Langeoog in the East Frisian Wadden Sea (southern North Sea). The processing steps will cover sensor drift, outlier identification, interpolation of data gaps and quality control. A central step is the removal of outliers. For this process an absolute threshold of 0.25 m/10 min was selected which still keeps the water level increase and decrease during extreme events as shown during the quality control process. A second important feature of data processing is the interpolation of gappy data which is accomplished with a high certainty of generating trustworthy data. Applying these methods a 10 years dataset of water level information at the TSS was processed and the results were submitted to WDC MARE data base system PANGAEA (http://doi.pangaea.de/10.1594/PANGAEA.843740).

  14. Processing of water level derived from water pressure data at the Time Series Station Spiekeroog

    NASA Astrophysics Data System (ADS)

    Holinde, L.; Badewien, T. H.; Freund, J. A.; Stanev, E. V.; Zielinski, O.

    2015-10-01

    The quality of water level time series data strongly varies with periods of high- and low-quality sensor data. In this paper we are presenting the processing steps which were used to generate high-quality water level data from water pressure measured at the Time Series Station (TSS) Spiekeroog. The TSS is positioned in a tidal inlet between the islands of Spiekeroog and Langeoog in the East Frisian Wadden Sea (southern North Sea). The processing steps will cover sensor drift, outlier identification, interpolation of data gaps and quality control. A central step is the removal of outliers. For this process an absolute threshold of 0.25 m 10 min-1 was selected which still keeps the water level increase and decrease during extreme events as shown during the quality control process. A second important feature of data processing is the interpolation of gappy data which is accomplished with a high certainty of generating trustworthy data. Applying these methods a 10-year data set (December 2002-December 2012) of water level information at the TSS was processed resulting in a 7-year time series (2005-2011). Supplementary data are available at doi:10.1594/PANGAEA.843740.

  15. Vibrio cholerae persisted in microcosm for 700 days inhibits motility but promotes biofilm formation in nutrient-poor lake water microcosms.

    PubMed

    Jubair, Mohammad; Atanasova, Kalina R; Rahman, Mustafizur; Klose, Karl E; Yasmin, Mahmuda; Yilmaz, Ozlem; Morris, J Glenn; Ali, Afsar

    2014-01-01

    Toxigenic Vibrio cholerae, ubiquitous in aquatic environments, is responsible for cholera; humans can become infected after consuming food and/or water contaminated with the bacterium. The underlying basis of persistence of V. cholerae in the aquatic environment remains poorly understood despite decades of research. We recently described a "persister" phenotype of V. cholerae that survived in nutrient-poor "filter sterilized" lake water (FSLW) in excess of 700-days. Previous reports suggest that microorganisms can assume a growth advantage in stationary phase (GASP) phenotype in response to long-term survival during stationary phase of growth. Here we report a V. cholerae GASP phenotype (GASP-700D) that appeared to result from 700 day-old persister cells stored in glycerol broth at -80°C. The GASP-700D, compared to its wild-type N16961, was defective in motility, produced increased biofilm that was independent of vps (p<0.005) and resistant to oxidative stress when grown specifically in FSLW (p<0.005). We propose that V. cholerae GASP-700D represents cell populations that may better fit and adapt to stressful survival conditions while serving as a critical link in the cycle of cholera transmission. PMID:24667909

  16. Improved inland water levels from SAR altimetry using novel empirical and physical retrackers

    NASA Astrophysics Data System (ADS)

    Villadsen, Heidi; Deng, Xiaoli; Andersen, Ole B.; Stenseng, Lars; Nielsen, Karina; Knudsen, Per

    2016-06-01

    Satellite altimetry has proven a valuable resource of information on river and lake levels where in situ data are sparse or non-existent. In this study several new methods for obtaining stable inland water levels from CryoSat-2 Synthetic Aperture Radar (SAR) altimetry are presented and evaluated. In addition, the possible benefits from combining physical and empirical retrackers are investigated. The retracking methods evaluated in this paper include the physical SAR Altimetry MOde Studies and Applications (SAMOSA3) model, a traditional subwaveform threshold retracker, the proposed Multiple Waveform Persistent Peak (MWaPP) retracker, and a method combining the physical and empirical retrackers. Using a physical SAR waveform retracker over inland water has not been attempted before but shows great promise in this study. The evaluation is performed for two medium-sized lakes (Lake Vänern in Sweden and Lake Okeechobee in Florida), and in the Amazon River in Brazil. Comparing with in situ data shows that using the SAMOSA3 retracker generally provides the lowest root-mean-squared-errors (RMSE), closely followed by the MWaPP retracker. For the empirical retrackers, the RMSE values obtained when comparing with in situ data in Lake Vänern and Lake Okeechobee are in the order of 2-5 cm for well-behaved waveforms. Combining the physical and empirical retrackers did not offer significantly improved mean track standard deviations or RMSEs. Based on these studies, it is suggested that future SAR derived water levels are obtained using the SAMOSA3 retracker whenever information about other physical properties apart from range is desired. Otherwise we suggest using the empirical MWaPP retracker described in this paper, which is both easy to implement, computationally efficient, and gives a height estimate for even the most contaminated waveforms.

  17. Analysis of water-level fluctuations in Wisconsin wells

    USGS Publications Warehouse

    Patterson, G.L.; Zaporozec, A.

    1987-01-01

    Long-term trends are apparent on hydrographs of wells Br-46, Mr-2S, Pt-276, Ro-3, and Ve-8. The trend of average annual water levels has been generally increasing since the late 1950's and is in general agreement with the increasing trend of precipitation. Hydrographs of well Ve-8, which has the longest period of record in Wisconsin, indicate that the generally rising trend started even earlier at the end of an extensive drought period in the 1930's.

  18. Projected climate change effects on water level of an oxbow

    NASA Astrophysics Data System (ADS)

    Hunyady, Adrienn

    One of the most vulnerable regions in the Carpathian Basin is the Great Hungarian Plain, where small and shallow oxbows are endangered along river Tisza. The purpose of this paper is to determine how the global warming affects a typical oxbow, located on the floodplain of river Tisza, in Hungary. A coupled meteorological-hydraulic model is developed and applied for this oxbow. Results suggest that the monthly minimum water levels are expected to decrease, moreover, extreme drought events sometimes result temporary drying-up of the oxbow.

  19. [Relationships between indices of persistent inflammatory pain response and the level of depression in prenatally stressed rats].

    PubMed

    Mikhaĭlenko, V A; Butkevich, I P; Vershinina, E A; Semenov, P O

    2008-12-01

    Relationships between behavioral indices of inflammatory pain response (the number of flexes + shakes) in the formalin test and the level of depression in forced swim in Porsolt test (immobility time) were investigated in 7-8-day-old male Wistar rats born to the dams exposed during the last week of pregnancy to immobilization stress. Two series of experiments differed in sequence of two testing procedures given 24 hr apart. In the first series of experiments Porsolt test was the first, in the second series, the formalin test preceded forced swim. It was found that the sequence of the tests effects differentially on the indices of the pain response and the level of depression as well as on their correlation in prenatally stressed (PS) and non-stressed (PNS) rats. No differences in the level of depression were apparent in PNS pups under both sequences of testing, whereas PS pups showed increase in the time of immobility in the first series of experiments. The sequence of testing had no effect on pain response indices. In the second series, the indices of pain response were increased in PS rats as compared to PNS ones. In PNS rats a positive correlation between the indices of the level of depression and the pain reaction was revealed, while in PS animals, a negative correlation was found. There was no significant dependence between the indices of depression and pain in the second series of experiments. Thus, effects of postnatal stress associated with both testing procedures applied before the final test are evident only in PS rats as to indices of the level of depression.

  20. Water Resources Data, Georgia, 2001, Volume 1: Continuous water-level, streamflow, water-quality data, and periodic water-quality data, Water Year 2001

    USGS Publications Warehouse

    McCallum, Brian E.; Kerestes, John F.; Hickey, Andrew C.

    2001-01-01

    Water resources data for the 2001 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in two volumes in a digital format on a CD-ROM. Volume one of this report contains water resources data for Georgia collected during water year 2001, including: discharge records of 133 gaging stations; stage for 144 gaging stations; precipitation for 58 gaging stations; information for 19 lakes and reservoirs; continuous water-quality records for 17 stations; the annual peak stage and annual peak discharge for 76 crest-stage partial-record stations; and miscellaneous streamflow measurements at 27 stations, and miscellaneous water-quality data recorded by the NAWQA program in Georgia. Volume two of this report contains water resources data for Georgia collected during calendar year 2001, including continuous water-level records of 159 ground-water wells and periodic records at 138 water-quality stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia. Note: Historically, this report was published as a paper report. For the 1999 and subsequent water-year reports, the Water Resources Data for Georgia changed to a new, more informative and functional format on CD-ROM. The format is based on a geographic information system (GIS) user interface that allows the user to view map locations of the hydrologic monitoring stations and networks within respective river basins.

  1. Levels of persistent organochlorine residues in eggs of greater flamingos from the Guadalquivir marshes (Doñana), Spain.

    PubMed

    Guitart, Raimon; Clavero, Raquel; Mateo, Rafael; Máñez, Manuel

    2005-01-01

    Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) residue levels were determined in 53 unhatched eggs from greater roseus flamingos (Phoenicopterus ruber). Eggs were collected in 1996 from the National Park of Doñana (Guadalquivir marshes, Southwest Spain), immediately after one breeding colony abandoned the nesting site due to predator attacks. The main metabolite of p,p'-DDT, p,p'-DDE, was the OCP residue found at higher concentrations, with a geometric mean of 721 ng/g wet weight. Residues of other pesticides, including some hexachlorocyclohexane isomers, hexachlorobenzene, aldrin, heptachlor, and heptachlor-epoxide, were detected at much lower concentrations. The sum of PCBs was 528 ng/g, with PCB congeners #187 and #153 being the most prominent in eggs. The pattern observed in these compounds of industrial origin corresponded more to Aroclor 1260 than to any other commercial mixture. Levels of organochlorine residues indicate a medium degree of exposure, and they are not considered of any concern for the flamingo population. In particular, neither p,p'-DDE nor PCB levels were found to be correlated with the eggshell thickness.

  2. Levels of persistent organochlorine residues in eggs of greater flamingos from the Guadalquivir marshes (Doñana), Spain.

    PubMed

    Guitart, Raimon; Clavero, Raquel; Mateo, Rafael; Máñez, Manuel

    2005-01-01

    Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) residue levels were determined in 53 unhatched eggs from greater roseus flamingos (Phoenicopterus ruber). Eggs were collected in 1996 from the National Park of Doñana (Guadalquivir marshes, Southwest Spain), immediately after one breeding colony abandoned the nesting site due to predator attacks. The main metabolite of p,p'-DDT, p,p'-DDE, was the OCP residue found at higher concentrations, with a geometric mean of 721 ng/g wet weight. Residues of other pesticides, including some hexachlorocyclohexane isomers, hexachlorobenzene, aldrin, heptachlor, and heptachlor-epoxide, were detected at much lower concentrations. The sum of PCBs was 528 ng/g, with PCB congeners #187 and #153 being the most prominent in eggs. The pattern observed in these compounds of industrial origin corresponded more to Aroclor 1260 than to any other commercial mixture. Levels of organochlorine residues indicate a medium degree of exposure, and they are not considered of any concern for the flamingo population. In particular, neither p,p'-DDE nor PCB levels were found to be correlated with the eggshell thickness. PMID:16190019

  3. Chiral persistent currents and magnetic susceptibilities in the parafermion quantum Hall states in the second Landau level with Aharonov-Bohm flux

    NASA Astrophysics Data System (ADS)

    Georgiev, Lachezar S.

    2004-02-01

    Using the effective conformal field theory for the quantum Hall edge states we propose a compact and convenient scheme for the computation of the periods, amplitudes, and temperature behavior of the chiral persistent currents and the magnetic susceptibilities in the mesoscopic disk version of the Zk parafermion quantum Hall states in the second Landau level. Our numerical calculations show that the persistent currents are periodic in the Aharonov Bohm flux with period exactly one flux quantum and have a diamagnetic nature. In the high-temperature regime their amplitudes decay exponentially with increasing the temperature and the corresponding exponents are universal characteristics of non-Fermi liquids. Our theoretical results for these exponents are in perfect agreement with those extracted from the numerical data and demonstrate that there is in general a nontrivial contribution coming from the neutral sector. We emphasize the crucial role of the nonholomorphic factors, first proposed by Cappelli and Zemba in the context of the conformal field theory partition functions for the quantum Hall states, which ensure the invariance of the annulus partition function under the Laughlin spectral flow.

  4. Degradation of Kresoxim-Methyl in Water: Impact of Varying pH, Temperature, Light and Atmospheric CO2 Level.

    PubMed

    Khandelwal, Ashish; Gupta, Suman; Gajbhiye, Vijay T; Varghese, Eldho

    2016-01-01

    In the present investigation, persistence of kresoxim-methyl (a broad spectrum strobilurin fungicide) was studied in water. Results revealed that kresoxim-methyl readily form acid metabolite. Therefore, residues of kresoxim-methyl were quantified on the basis of parent molecule alone and sum total of kresoxim-methyl and its acid metabolite. In water, influence of various abiotic factors like pH, temperature, light and atmospheric carbon dioxide level on dissipation of kresoxim-methyl was studied. The half life value for kresoxim-methyl and total residue varied from 1 to 26.1 and 6.1 to 94.0 days under different conditions. Statistical analysis revealed the significant effect of abiotic factors on the dissipation of kresoxim-methyl from water.

  5. RELATIONSHIPS BETWEEN LEVELS OF HETEROTROPHIC BACTERIA AND WATER QUALITY PARAMETERS IN A DRINKING WATER DISTRIBUTION SYSTEM

    EPA Science Inventory

    Conventional plating methods were used to quantify heterotrophic bacteria from a drinking water distribution system. Three media, plate count agar (PCA), R2A agar and sheep blood agar (TSA-SB) were used to determine heterotrophic plate count (HPC) levels. Grab samples were collec...

  6. Persistent organochlorine compounds in peregrine falcon (Falco peregrinus) eggs from South Greenland: levels and temporal changes between 1986 and 2003.

    PubMed

    Vorkamp, Katrin; Thomsen, Marianne; Møller, Søren; Falk, Knud; Sørensen, Peter B

    2009-02-01

    Thirty-seven addled peregrine falcon eggs collected in South Greenland between 1986 and 2003 were analysed for their content of the organochlorine compounds polychlorinated biphenyls (PCBs), dichlorodiphenyl tricloroethane (DDT) and its degradation products, hexachlorocyclohexane (HCH) isomers and hexachlorobenzene (HCB). PCBs and DDT (including metabolites) were by far the most abundant OC groups, with median concentrations of 55 and 40 microg/g lw, respectively. The concentrations were high in an Arctic context, but similar to previously reported levels from Alaska and Norway and slightly lower than concentrations measured in eggs from industrialised regions. Geographical differences may be of importance, considering the migration of peregrine falcons and their prey. SigmaHCH and HCB had median concentrations of 0.39 and 0.17 microg/g lw, respectively. On average, DDE accounted for 97% of SigmaDDT, but was below critical levels for eggshell thinning. All compound groups showed a weak decreasing trend over the study period, which was statistically significant for HCB and close to being significant for SigmaHCH. The weak decrease of SigmaPCB and SigmaDDT is different from other time trend studies from Greenland, usually showing a more pronounced decrease in the beginning of the study period, followed by a certain stabilisation in recent years. PMID:18823663

  7. Water-level maps of the alluvial aquifer, northwestern Mississippi, September 1982

    USGS Publications Warehouse

    Darden, Daphne

    1983-01-01

    Water levels were measured in about 500 wells in the Mississippi River valley alluvial aquifer in northwestern Mississippi during September 13-24, 1982. The water-level change from September 1981 to September 1982 showed some recovery, but the depth-to-water map showed areas of continual water-level decline in the central part of the Delta. Water levels in the Delta were higher along the Mississippi River and Bluff Hills and Yazoo River. Historically, water levels decline and rise as the amount of precipitation decreases or increases. Recently, continuous heavy pumping for irrigation has caused general water-level declines in the alluvial aquifer. (USGS)

  8. Semibiotic Persistence

    NASA Astrophysics Data System (ADS)

    Prothmann, C.; Zauner, K.-P.

    From observation, we find four different strategies to successfully enable structures to persist over extended periods of time. If functionally relevant features are very large compared to the changes that can be effectuated by entropy, the functional structure itself has a high enough probability to erode only slowly over time. If the functionally relevant features are protected from environmental influence by sacrificial layers that absorb the impinging of the environment, deterioration can be avoided or slowed. Loss of functionality can be delayed, even for complex systems, by keeping alternate options for all required components available. Biological systems also apply information processing to actively counter the impact of entropy by mechanisms such as self-repair. The latter strategy increases the overall persistence of living systems and enables them to maintain a highly complex functional organisation during their lifetime and over generations. In contrast to the other strategies, information processing has only low material overhead. While at present engineered technology is far from achieving the self-repair of evolved systems, the semibiotic combination of biological components with conventionally engineered systems may open a path to long-term persistence of functional devices in harsh environments. We review nature's strategies for persistence, and consider early steps taken in the laboratory to import such capabilities into engineered architectures.

  9. High levels of mercury and low levels of persistent organic pollutants in a tropical seabird in French Guiana, the Magnificent frigatebird, Fregata magnificens.

    PubMed

    Sebastiano, Manrico; Bustamante, Paco; Costantini, David; Eulaers, Igor; Malarvannan, Govindan; Mendez-Fernandez, Paula; Churlaud, Carine; Blévin, Pierre; Hauselmann, Antoine; Dell'Omo, Giacomo; Covaci, Adrian; Eens, Marcel; Chastel, Olivier

    2016-07-01

    In the present study, trace elements and persistent organic pollutants (POPs) were quantified from Magnificent frigatebirds (Fregata magnificens) breeding at a southern Atlantic island. Stable isotope ratio of carbon (δ(13)C) and nitrogen (δ(15)N) were also measured to infer the role of foraging habitat on the contamination. For another group from the same colony, GPS tracks were recorded to identify potential foraging areas where the birds may get contaminated. Fourteen trace elements were targeted as well as a total of 40 individual POPs, including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). The concentration of Hg in the blood was up to 6 times higher in adults (5.81 ± 1.27 μg g(-1) dw.) than in nestlings (0.99 ± 0.23 μg g(-1) dw.). A similar pattern was found for POPs. ∑PCBs was the prevalent group both in adults (median 673, range 336-2801 pg g(-1) ww.) and nestlings (median 41, range 19-232 pg g(-1) ww.), followed by the sum of dichlorodiphenyltrichloroethanes and metabolites (∑DDTs), showing a median value of 220 (range 75-2342 pg g(-1) ww.) in adults and 25 (range 13-206 pg g(-1) ww.) in nestlings. The isotope data suggested that the accumulation of trace elements and POPs between adults and nestlings could be due to parental foraging in two different areas during incubation and chick rearing, respectively, or due to a shift in the feeding strategies along the breeding season. In conclusion, our work showed high Hg concentration in frigatebirds compared to non-contaminated seabird populations, while other trace elements showed lower values within the expected range in other seabird species. Finally, POP exposure was found generally lower than that previously measured in other seabird species.

  10. Evaluation of long-term water-level declines in basalt aquifers near Mosier, Oregon

    USGS Publications Warehouse

    Burns, Erick R.; Morgan, David S.; Lee, Karl K.; Haynes, Jonathan V.; Conlon, Terrence D.

    2012-01-01

    The Mosier area lies along the Columbia River in northwestern Wasco County between the cities of Hood River and The Dalles, Oregon. Major water uses in the area are irrigation, municipal supply for the city of Mosier, and domestic supply for rural residents. The primary source of water is groundwater from the Columbia River Basalt Group (CRBG) aquifers that underlie the area. Concerns regarding this supply of water arose in the mid-1970s, when groundwater levels in the orchard tract area began to steadily decline. In the 1980s, the Oregon Water Resources Department (OWRD) conducted a study of the aquifer system, which resulted in delineation of an administrative area where parts of the Pomona and Priest Rapids aquifers were withdrawn from further appropriations for any use other than domestic supply. Despite this action, water levels continued to drop at approximately the same, nearly constant annual rate of about 4 feet per year, resulting in a current total decline of between 150 and 200 feet in many wells with continued downward trends. In 2005, the Mosier Watershed Council and the Wasco Soil and Water Conservation District began a cooperative investigation of the groundwater system with the U.S. Geological Survey. The objectives of the study were to advance the scientific understanding of the hydrology of the basin, to assess the sustainability of the water supply, to evaluate the causes of persistent groundwater-level declines, and to evaluate potential management strategies. An additional U.S. Geological Survey objective was to advance the understanding of CRBG aquifers, which are the primary source of water across a large part of Oregon, Washington, and Idaho. In many areas, significant groundwater level declines have resulted as these aquifers were heavily developed for agricultural, municipal, and domestic water supplies. Three major factors were identified as possible contributors to the water-level declines in the study area: (1) pumping at rates that

  11. Induced Sputum Nitrite Levels Correlate with Clinical Asthma Parameters in Children Aged 7–18 Years with Mild to Moderate Persistent Asthma

    PubMed Central

    Nandan, Devki; Kansal, Prachi; Patharia, Neha; Goyal, Parul

    2016-01-01

    Purpose: The objective of this study is to measure levels of nitrites in induced sputum in children with asthma and correlate it with clinical asthma parameters. Method: This prospective observational study was done in PGIMER, Dr. Ram Manohar Lohia Hospital, New Delhi, on 91 children aged 7-18 years with mild and moderate persistent asthma. Patients were specifically evaluated for five clinical parameters of asthma (i.e. Days of acute exacerbations, use of salbutamol as rescue medication, emergency visits, nights with cough, days of school absence) and induced sputum nitrite levels was done at the time of enrollment and 3 months after treatment with inhaled budesonide. Results: The mean age of subjects was 10.79 ± 2.563yrs. Six (6.59%) patients were not able to perform induced sputum, eighty five (93.41%) patients were suitable for data analysis. There was significant reduction in sputum nitrite levels from 33.42 ± 22.04nmol/ml at enrollment to 11.72 ± 5.61 nmol/ml (P < 0.0005) after 3 months of inhaled budesonide therapy. Significant positive correlation was found between reduction in sputum nitrite level and control of asthma symptoms: Days of acute exacerbations(r value = 0.548, P value = 0.0001), Days of salbutamol use as rescue medication (r value = 0.431, P value =< 0.0001), Number of emergency visits(r value = 0.414, P value = 0.0001), Nights with cough (r value = 0.259, P value = 0.0169), Days of school absence(r value = 0.411, P value = 0.0001). Sputum nitrite levels were significantly higher in moderate persistent asthmatics as compared to mild at the time of enrollment (P < 0.0005), which shows that induced sputum nitrite levels correlate with asthma severity. Conclusions: This study confirms that nitrites in induced sputum correlate well with clinical asthma parameters and asthma severity in children and is a simple, non invasive, and cheap method which can be used as a parameter for monitoring of asthma. PMID:27365917

  12. Project Water Science. General Science High School Level.

    ERIC Educational Resources Information Center

    Water Education Foundation, Sacramento, CA.

    This teacher's guide presents 12 hands-on laboratory activities for high school science classes that cover the environmental issue of water resources in California. The activities are separated into three sections. Five activities in the section on water quality address the topics of groundwater, water hardness, bottled water, water purity, and…

  13. Association between Several Persistent Organic Pollutants and Thyroid Hormone Levels in Cord Blood Serum and Bloodspot of the Newborn Infants of Korea.

    PubMed

    Kim, Sunmi; Park, Jeongim; Kim, Hai-Joong; Lee, Jeong Jae; Choi, Gyuyeon; Choi, Sooran; Kim, Sungjoo; Kim, Su Young; Moon, Hyo-Bang; Kim, Sungkyoon; Choi, Kyungho

    2015-01-01

    Current knowledge on adverse endocrine disruption effects of persistent organic pollutants (POPs) among newborn infants is limited and often controversial. To investigate the associations between prenatal exposure to major POPs and thyroid hormone levels among newborn infants, both cord serum or maternal serum concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) were compared with five thyroid hormones in cord serum of newborn infants as well as TSH in bloodspot collected at 2 day after birth (n=104). Since cord serum thyroid hormones could be affected by those of mothers, thyroid hormone concentrations of the matching mothers at delivery were adjusted. In cord serum, BDE-47, -99, and Σchlordane (CHD) showed significant positive associations with cord or bloodspot TSH. At the same time, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorbenzene (HCB) showed negative associations with total T3 and total T4 in cord serum, respectively. Maternal exposure to β-hexachlorhexane (β-HCH), ΣCHD, ΣDDT, or p,p'-DDE were also associated with neonatal thyroid hormones. Although the sample size is small and the thyroid hormone levels of the subjects were within the reference range, our observation supports thyroid disrupting potential of several POPs among newborn infants, at the levels occurring in the general population. Considering the importance of thyroid hormones during gestation and early life stages, health implication of thyroid hormone effects by low level POPs exposure deserves further follow up investigations. PMID:25965908

  14. Association between Several Persistent Organic Pollutants and Thyroid Hormone Levels in Cord Blood Serum and Bloodspot of the Newborn Infants of Korea.

    PubMed

    Kim, Sunmi; Park, Jeongim; Kim, Hai-Joong; Lee, Jeong Jae; Choi, Gyuyeon; Choi, Sooran; Kim, Sungjoo; Kim, Su Young; Moon, Hyo-Bang; Kim, Sungkyoon; Choi, Kyungho

    2015-01-01

    Current knowledge on adverse endocrine disruption effects of persistent organic pollutants (POPs) among newborn infants is limited and often controversial. To investigate the associations between prenatal exposure to major POPs and thyroid hormone levels among newborn infants, both cord serum or maternal serum concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) were compared with five thyroid hormones in cord serum of newborn infants as well as TSH in bloodspot collected at 2 day after birth (n=104). Since cord serum thyroid hormones could be affected by those of mothers, thyroid hormone concentrations of the matching mothers at delivery were adjusted. In cord serum, BDE-47, -99, and Σchlordane (CHD) showed significant positive associations with cord or bloodspot TSH. At the same time, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorbenzene (HCB) showed negative associations with total T3 and total T4 in cord serum, respectively. Maternal exposure to β-hexachlorhexane (β-HCH), ΣCHD, ΣDDT, or p,p'-DDE were also associated with neonatal thyroid hormones. Although the sample size is small and the thyroid hormone levels of the subjects were within the reference range, our observation supports thyroid disrupting potential of several POPs among newborn infants, at the levels occurring in the general population. Considering the importance of thyroid hormones during gestation and early life stages, health implication of thyroid hormone effects by low level POPs exposure deserves further follow up investigations.

  15. Association between Several Persistent Organic Pollutants and Thyroid Hormone Levels in Cord Blood Serum and Bloodspot of the Newborn Infants of Korea

    PubMed Central

    Kim, Sunmi; Park, Jeongim; Kim, Hai-Joong; Lee, Jeong Jae; Choi, Gyuyeon; Choi, Sooran; Kim, Sungjoo; Kim, Su Young; Moon, Hyo-Bang; Kim, Sungkyoon; Choi, Kyungho

    2015-01-01

    Current knowledge on adverse endocrine disruption effects of persistent organic pollutants (POPs) among newborn infants is limited and often controversial. To investigate the associations between prenatal exposure to major POPs and thyroid hormone levels among newborn infants, both cord serum or maternal serum concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) were compared with five thyroid hormones in cord serum of newborn infants as well as TSH in bloodspot collected at 2 day after birth (n=104). Since cord serum thyroid hormones could be affected by those of mothers, thyroid hormone concentrations of the matching mothers at delivery were adjusted. In cord serum, BDE-47, -99, and Σchlordane (CHD) showed significant positive associations with cord or bloodspot TSH. At the same time, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorbenzene (HCB) showed negative associations with total T3 and total T4 in cord serum, respectively. Maternal exposure to β-hexachlorhexane (β-HCH), ΣCHD, ΣDDT, or p,p'-DDE were also associated with neonatal thyroid hormones. Although the sample size is small and the thyroid hormone levels of the subjects were within the reference range, our observation supports thyroid disrupting potential of several POPs among newborn infants, at the levels occurring in the general population. Considering the importance of thyroid hormones during gestation and early life stages, health implication of thyroid hormone effects by low level POPs exposure deserves further follow up investigations. PMID:25965908

  16. Contrasting levels of connectivity and localised persistence characterise the latitudinal distribution of a wind-dispersed rainforest canopy tree.

    PubMed

    Heslewood, Margaret M; Lowe, Andrew J; Crayn, Darren M; Rossetto, Maurizio

    2014-06-01

    Contrasting signals of genetic divergence due to historic and contemporary gene flow were inferred for Coachwood, Ceratopetalum apetalum (Cunoniaceae), a wind-dispersed canopy tree endemic to eastern Australian warm temperate rainforest. Analysis of nine nuclear microsatellites across 22 localities revealed two clusters between northern and southern regions and with vicariance centred on the wide Hunter River Valley. Within populations diversity was high indicating a relatively high level of pollen dispersal among populations. Genetic variation was correlated to differences in regional biogeography and ecology corresponding to IBRA regions, primary factors being soil type and rainfall. Eleven haplotypes were identified by chloroplast microsatellite analysis from the same 22 localities. A lack of chloroplast diversity within sites demonstrates limited gene flow via seed dispersal. Network representation indicated regional sharing of haplotypes indicative of multiple Pleistocene refugia as well as deep divergences between regional elements of present populations. Chloroplast differentiation between sites in the upper and lower sections of the northern population is reflective of historic vicariance at the Clarence River Corridor. There was no simple vicariance explanation for the distribution of the divergent southern chlorotype, but its distribution may be explained by the effects of drift from a larger initial gene pool. Both the Hunter and Clarence River Valleys represent significant dry breaks within the species range, consistent with this species being rainfall dependent rather than cold-adapted.

  17. Levels and patterns of persistent organic pollutants (POPs) in tilapia (Oreochromis sp.) from four different lakes in Tanzania: geographical differences and implications for human health.

    PubMed

    Polder, A; Müller, M B; Lyche, J L; Mdegela, R H; Nonga, H E; Mabiki, F P; Mbise, T J; Skaare, J U; Sandvik, M; Skjerve, E; Lie, E

    2014-08-01

    In Tanzania fish is one of the most important protein sources for the rapidly increasing population. Wild fish is threatened by overfishing and pollution from agriculture, industries, mining, household effluents and vector control. To monitor possible implications for public health, the geographical differences of the occurrence and levels of persistent organic pollutants (POPs) in tilapia fish (Oreochromis sp.) from four different Tanzanian lakes were investigated in 2011. Concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyls (PBDEs) and hexabromocyclododecane (HBCDD) were determined in pooled samples of tilapia muscle from Lake (L) Victoria, L. Tanganyika, L. Nyasa (also called L. Malawi) and L. Babati in Tanzania in 2011. Levels of Σ-DDTs (274 ng/g lipid weight (lw)) and sum of 7 indicator PCBs (Σ-7PCBs) (17 ng/g lw) were significantly higher in tilapia from L. Tanganyika compared to the other lakes. The highest levels of Σ-endosulfan (94 ng/g lw) were detected in tilapia from L. Victoria. Toxaphenes were detected in low levels in fish from L. Tanganyika and L. Babati. Results revealed a geographic difference in the use of DDT and endosulfan between L. Victoria and L. Tanganyika. Low ratios of DDE/DDT in tilapia from L. Tanganyika indicated an on-going use of DDT in the area. Median levels of ΣBDEs, including BDE-209, were highest in L. Victoria (19.4 ng/g lw) and BDE-209 was present in 68% of the samples from this lake. The presence of BDE-209 indicates increasing influence of imported products from heavy industrialized countries. The measured POP levels in the studied tilapia were all below MRLs of EU or were lower than recommended levels, and thus the fish is considered as safe for human consumption. They may, however, pose a risk to the fish species and threaten biodiversity. PMID:24836134

  18. Both long and brief maternal separation produces persistent changes in tissue levels of brain monoamines in middle-aged female rats.

    PubMed

    Arborelius, L; Eklund, M B

    2007-03-16

    Adverse experiences early in life are associated with an increased incidence of later psychopathology including depression. Based on evidence that dysfunction of central monoaminergic systems is involved in the pathophysiology of depression, we hypothesize that early adversity could negatively affect these systems. To test this we have investigated the effects of maternal separation, which has been suggested to model early-life stress and the development of a depression-like syndrome in the rat, on brain monoaminergic systems. Since depression is more common in women and the risk of developing this disorder appears to increase with age, we have studied such effects in middle-aged female rats. Rat pups were separated for 180 min (long maternal separation; LMS) or 15 min (brief maternal separation; BMS, often referred to as neonatal handling) twice daily for 2 weeks postpartum. An animal facility-reared (AFR) group was also included. At 15 months of age tissue levels of monoamines and their metabolites in several different brain regions were analyzed. In the LMS females tissue levels of both 5-HT and 5-hydroxyindole acetic acid (5-HIAA) were significantly increased in the dorsal raphe nucleus, and 5-HIAA and homovanillic acid levels were also elevated in the nucleus accumbens as compared with AFR and BMS rats. In the cingulate cortex both LMS and BMS decreased noradrenaline (NA) levels, although this effect was more pronounced in the LMS rats. On the other hand, BMS decreased 5-HT, 5-HIAA, dopamine (DA) as well as NA levels in the amygdala and produced an increase in DA levels in response to acute stress in the hypothalamus, an effect not seen in AFR rats. Our results demonstrate that LMS produced persistent alterations in both serotonergic, noradrenergic and dopaminergic systems in brain regions that have been suggested to be implicated in the pathophysiology of depression. In addition, BMS affected brain monoaminergic levels mainly in the amygdala.

  19. Levels and patterns of persistent organic pollutants (POPs) in tilapia (Oreochromis sp.) from four different lakes in Tanzania: geographical differences and implications for human health.

    PubMed

    Polder, A; Müller, M B; Lyche, J L; Mdegela, R H; Nonga, H E; Mabiki, F P; Mbise, T J; Skaare, J U; Sandvik, M; Skjerve, E; Lie, E

    2014-08-01

    In Tanzania fish is one of the most important protein sources for the rapidly increasing population. Wild fish is threatened by overfishing and pollution from agriculture, industries, mining, household effluents and vector control. To monitor possible implications for public health, the geographical differences of the occurrence and levels of persistent organic pollutants (POPs) in tilapia fish (Oreochromis sp.) from four different Tanzanian lakes were investigated in 2011. Concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyls (PBDEs) and hexabromocyclododecane (HBCDD) were determined in pooled samples of tilapia muscle from Lake (L) Victoria, L. Tanganyika, L. Nyasa (also called L. Malawi) and L. Babati in Tanzania in 2011. Levels of Σ-DDTs (274 ng/g lipid weight (lw)) and sum of 7 indicator PCBs (Σ-7PCBs) (17 ng/g lw) were significantly higher in tilapia from L. Tanganyika compared to the other lakes. The highest levels of Σ-endosulfan (94 ng/g lw) were detected in tilapia from L. Victoria. Toxaphenes were detected in low levels in fish from L. Tanganyika and L. Babati. Results revealed a geographic difference in the use of DDT and endosulfan between L. Victoria and L. Tanganyika. Low ratios of DDE/DDT in tilapia from L. Tanganyika indicated an on-going use of DDT in the area. Median levels of ΣBDEs, including BDE-209, were highest in L. Victoria (19.4 ng/g lw) and BDE-209 was present in 68% of the samples from this lake. The presence of BDE-209 indicates increasing influence of imported products from heavy industrialized countries. The measured POP levels in the studied tilapia were all below MRLs of EU or were lower than recommended levels, and thus the fish is considered as safe for human consumption. They may, however, pose a risk to the fish species and threaten biodiversity.

  20. Population-Level Persistence of Immunity 2 Years After the PsA-TT Mass-Vaccination Campaign in Mali

    PubMed Central

    Basta, Nicole E.; Borrow, Ray; Berthe, Abdoulaye; Dembélé, Awa Traoré Eps; Onwuchekwa, Uma; Townsend, Kelly; Boukary, Rahamatou M.; Mabey, Lesley; Findlow, Helen; Bai, Xilian; Sow, Samba O.

    2015-01-01

    Background. In 2010, Africa's first preventive meningococcal mass vaccination campaign was launched using a newly developed Neisseria meningitidis group A (NmA) polysaccharide–tetanus toxoid conjugate vaccine, PsA-TT (MenAfriVac), designed specifically for the meningitis belt. Given PsA-TT's recent introduction, the duration of protection against meningococcal group A is unknown. Methods. We conducted a household-based, age-stratified seroprevalence survey in Bamako, Mali, in 2012, 2 years after the vaccination campaign targeted all 1- to 29-year-olds. Randomly selected participants who had been eligible for PsA-TT provided a blood sample and responded to a questionnaire. Sera were analyzed to assess NmA-specific serum bactericidal antibody titers using rabbit complement (rSBA) and NmA-specific immunoglobulin G (IgG) by enzyme-linked immunosorbent assay. The proportion of participants putatively protected and the age group- and sex-specific rSBA geometric mean titers (GMTs) and IgG geometric mean concentrations (GMCs) were determined. Results. Two years postvaccination, nearly all of the 800 participants (99.0%; 95% confidence interval [CI], 98.3%–99.7%) maintained NmA-specific rSBA titers ≥8, the accepted threshold for protection; 98.6% (95% CI, 97.8%–99.4%) had titers ≥128, and 89.5% (95% CI, 87.4%–91.6%) had titers ≥1024. The rSBA GMTs were significantly higher in females than in males aged <18 years at vaccination (P < .0001). NmA-specific IgG levels ≥2 µg/mL were found in 88.5% (95% CI, 86.3%–90.7%) of participants. Conclusions. Two years after PsA-TT introduction, a very high proportion of the population targeted for vaccination maintains high antibody titers against NmA. Assessing the duration of protection provided by PsA-TT is a priority for implementing evidence-based vaccination strategies. Representative, population-based seroprevalence studies complement clinical trials and provide this key evidence. PMID:26553687

  1. Ground-water levels near the top of the water-table mound, western Cape Cod, Massachusetts, 2002-04

    USGS Publications Warehouse

    Massey, Andrew J.; Carlson, Carl S.; LeBlanc, Denis R.

    2006-01-01

    In January 2002 the U.S. Geological Survey began continuous water-level monitoring in three wells in the vicinity of the Southeast Ranges of Camp Edwards, near the Impact Area of the Massachusetts Military Reservation on Cape Cod. The purpose of this effort was to examine how water levels at sites with different unsaturated-zone thicknesses near the top of the water-table mound beneath western Cape Cod are affected by temporally variable recharge from precipitation, which is the sole source of water to the sand and gravel aquifer. The depths to water at the well sites are about 18, 30, and 101 feet below land surface. This report presents the first 3 years of water-level records and an estimate of aquifer recharge calculated from climatological measurements by the Jensen and Haise method and the Thornthwaite method. The water levels in the three wells varied temporally by about 4.5 feet during the study period. A comparison of the water levels with those measured in a nearby monitoring well with about 42 years of monthly measurements indicates that the 3-year monitoring period included the lowest water levels on western Cape Cod since the drought of the 1960's. The response of water levels to recharge was related to the depth to water. Water levels in the two wells with shallow depths to water responded quickly (within hours or days) to recharge, whereas the water-level response in the well with the greatest depth to water often lagged the recharge event by a month or more. The variations in the water levels among the wells changed as the location of the top of the water-table mound moved with the changing water-table altitude.

  2. Water-level maps of the alluvial aquifer northwestern Mississippi, April 1982

    USGS Publications Warehouse

    Darden, Daphne

    1982-01-01

    Water levels were measured in about 500 wells in the Mississippi River valley alluvial aquifer in northwestern Mississippi during the period April 12-23, 1982. The water-level change from April 1981 to April 1982, showed a general decline, but the water-level change from September 1981 to April 1982 showed some recovery. Water levels in the Delta were higher along the Mississippi River and Bluff Hills. Historically, water levels decline and rise as the amount of precipitation decreases or increases. Recently, continuous heavy pumping for irrigation has caused general water-level declines in the alluvial aquifer. (USGS)

  3. Tidal phase of Water level lags behind that of water temperature in Qi'xian observation well, China

    NASA Astrophysics Data System (ADS)

    Wang, B.; Ma, Y.; Huang, F.

    2014-12-01

    There are about 34 observation wells of water temperature which can record the effect of earth tide in national earthquake precursory network center. In most of the 34 wells, tidal phase of water temperature lag behind that of water level, but the opposite phenomenon exists in several observation wells. We take Qi'xian well which has long recording history and continuous data as an example to analyze this phenomenon. We check the instrument's time system by using water temperature and water level changes in response to some big earthquakes,and also check the tidal phase of water temperature and water level in Qi'xian well through harmonic analysis (Baytap-G software), as a result,we find the observation is objective. The fact that Tidal phase of Water level lags behind that of water temperature in Qi'xian observation well shows that water temperature changes may be independent from water level changes. Water temperature changes in this well might be interpreted by the stress-heat consumption hypothesis. This may be beneficial to the study of water temperature changes as an earthquake precursor. Figure 1. Water temperature and water level records of the Qi'xian well from February 26 to 27 in 2010.The coseismic changes due to the 2010 Sumatra earthquake is marked by an arrow.

  4. Addressing barriers to the prevention, diagnosis and treatment of hepatitis B and C in the face of persisting fiscal constraints in Europe: report from a high level conference.

    PubMed

    Papatheodoridis, G; Thomas, H C; Golna, C; Bernardi, M; Carballo, M; Cornberg, M; Dalekos, G; Degertekin, B; Dourakis, S; Flisiak, R; Goldberg, D; Gore, C; Goulis, I; Hadziyannis, S; Kalamitsis, G; Kanavos, P; Kautz, A; Koskinas, I; Leite, B R; Malliori, M; Manolakopoulos, S; Matičič, M; Papaevangelou, V; Pirona, A; Prati, D; Raptopoulou-Gigi, M; Reic, T; Robaeys, G; Schatz, E; Souliotis, K; Tountas, Y; Wiktor, S; Wilson, D; Yfantopoulos, J; Hatzakis, A

    2016-02-01

    In the WHO-EURO region, around 28 million people are currently living with chronic viral hepatitis, and 120,000 people die every year because of it. Lack of awareness and understanding combined with the social stigma and discrimination exacerbate barriers related to access to prevention, diagnosis and treatment services for those most in need. In addition, the persisting economic crisis has impacted on public health spending, thus posing challenges on the sustainable investment in promotion, primary and secondary prevention, diagnosis and treatment of viral hepatitis across European countries. The Hepatitis B and C Public Policy Association in cooperation with the Hellenic Center for Disease Prevention and Control together with 10 partner organizations discussed at the Athens High Level Meeting held in June 2014 recent policy developments, persisting and emerging challenges related to the prevention and management of viral hepatitis and the need for a de minimis framework of urgent priorities for action, reflected in a Call to Action (Appendix S1). The discussion confirmed that persisting barriers do not allow the full realisation of the public health potential of diagnosing and preventing hepatitis B and C, treating hepatitis B and curing hepatitis C. Such barriers are related to (a) lack of evidence-based knowledge of hepatitis B and C, (b) limited access to prevention, diagnosis and treatment services with poor patient pathways, (c) declining resources and (d) the presence of social stigma and discrimination. The discussion also confirmed the emerging importance of fiscal constraints on the ability of policymakers to adequately address viral hepatitis challenges, particularly through increasing coverage of newer therapies. In Europe, it is critical that public policy bodies urgently agree on a conceptual framework for addressing the existing and emerging barriers to managing viral hepatitis. Such a framework would ensure all health systems share a common

  5. Addressing barriers to the prevention, diagnosis and treatment of hepatitis B and C in the face of persisting fiscal constraints in Europe: report from a high level conference.

    PubMed

    Papatheodoridis, G; Thomas, H C; Golna, C; Bernardi, M; Carballo, M; Cornberg, M; Dalekos, G; Degertekin, B; Dourakis, S; Flisiak, R; Goldberg, D; Gore, C; Goulis, I; Hadziyannis, S; Kalamitsis, G; Kanavos, P; Kautz, A; Koskinas, I; Leite, B R; Malliori, M; Manolakopoulos, S; Matičič, M; Papaevangelou, V; Pirona, A; Prati, D; Raptopoulou-Gigi, M; Reic, T; Robaeys, G; Schatz, E; Souliotis, K; Tountas, Y; Wiktor, S; Wilson, D; Yfantopoulos, J; Hatzakis, A

    2016-02-01

    In the WHO-EURO region, around 28 million people are currently living with chronic viral hepatitis, and 120,000 people die every year because of it. Lack of awareness and understanding combined with the social stigma and discrimination exacerbate barriers related to access to prevention, diagnosis and treatment services for those most in need. In addition, the persisting economic crisis has impacted on public health spending, thus posing challenges on the sustainable investment in promotion, primary and secondary prevention, diagnosis and treatment of viral hepatitis across European countries. The Hepatitis B and C Public Policy Association in cooperation with the Hellenic Center for Disease Prevention and Control together with 10 partner organizations discussed at the Athens High Level Meeting held in June 2014 recent policy developments, persisting and emerging challenges related to the prevention and management of viral hepatitis and the need for a de minimis framework of urgent priorities for action, reflected in a Call to Action (Appendix S1). The discussion confirmed that persisting barriers do not allow the full realisation of the public health potential of diagnosing and preventing hepatitis B and C, treating hepatitis B and curing hepatitis C. Such barriers are related to (a) lack of evidence-based knowledge of hepatitis B and C, (b) limited access to prevention, diagnosis and treatment services with poor patient pathways, (c) declining resources and (d) the presence of social stigma and discrimination. The discussion also confirmed the emerging importance of fiscal constraints on the ability of policymakers to adequately address viral hepatitis challenges, particularly through increasing coverage of newer therapies. In Europe, it is critical that public policy bodies urgently agree on a conceptual framework for addressing the existing and emerging barriers to managing viral hepatitis. Such a framework would ensure all health systems share a common

  6. Global Anthropogenic Phosphorus Loads to Fresh Water, Grey Water Footprint and Water Pollution Levels: A High-Resolution Global Study

    NASA Astrophysics Data System (ADS)

    Mekonnen, M. M.; Hoekstra, A. Y. Y.

    2014-12-01

    We estimated anthropogenic phosphorus (P) loads to freshwater, globally at a spatial resolution level of 5 by 5 arc minute. The global anthropogenic P load to freshwater systems from both diffuse and point sources in the period 2002-2010 was 1.5 million tonnes per year. China contributed about 30% to this global anthropogenic P load. India was the second largest contributor (8%), followed by the USA (7%), Spain and Brazil each contributing 6% to the total. The domestic sector contributed the largest share (54%) to this total followed by agriculture (38%) and industry (8%). Among the crops, production of cereals had the largest contribution to the P loads (32%), followed by fruits, vegetables, and oil crops, each contributing about 15% to the total. We also calculated the resultant grey water footprints, and relate the grey water footprints per river basin to runoff to calculate the P-related water pollution level (WPL) per catchment.

  7. Status of Water Levels and Selected Water-Quality Conditions in the Mississippi River Valley Alluvial Aquifer in Eastern Arkansas, 2004

    USGS Publications Warehouse

    Schrader, T.P.

    2006-01-01

    During the spring of 2004, water levels were measured in 684 wells completed in the Mississippi River Valley alluvial aquifer in eastern Arkansas. Ground-water levels are affected by intense ground-water withdrawals resulting in extensive potentiometric depressions. In 2004, the highest water-level altitude measured was 293 feet above National Geodetic Vertical Datum of 1929 in northeastern Clay County. The lowest water-level altitude measured was 76 feet above National Geodetic Vertical Datum of 1929 in the center of Arkansas County. A large depression in the potentiometric surface was located in Arkansas, Lonoke, and Prairie Counties during 1998 and persisted to 2002. The area enclosed in the 100-foot contour in Arkansas County in 2004 is about the same as in 2002, however, the area enclosed in the 100-foot contour in Lonoke and Prairie Counties in 2004 has receded. Two shallower cones of depressions were located in Craighead, Cross, and Poinsett Counties and St. Francis, Woodruff, Lee, and Monroe Counties west of Crowleys Ridge during 1998. The 2004 potentiometricsurface map shows that the areas enclosed by the 140-foot contour have continued to expand. A map of changes in water-level measurements between 2000 and 2004 was constructed using the difference between water-level measurements from 625 wells reported in this report and the 2000 Mississippi River Valley alluvial aquifer report. Water-level changes between 2000 and 2004 ranged from -31.1 feet to 16.3 feet, with a mean of -0.7 feet (negative changes indicating water-level declines, positive changes indicating water-level rises). The largest rise of 16.3 feet is in Arkansas County and the largest decline of -31.1 feet is in Prairie County. Long-term water-level changes were calculated for 134 wells in the alluvial aquifer for the period from 1980 to 2004. The mean annual decline in water level for the entire study area was -0.31 feet per year with a range of -1.35 feet per year to 0.84 feet per year. The

  8. Effects of sea-level rise on ground water flow in a coastal aquifer system

    USGS Publications Warehouse

    Masterson, J.P.; Garabedian, S.P.

    2007-01-01

    The effects of sea-level rise on the depth to the fresh water/salt water interface were simulated by using a density-dependent, three-dimensional numerical ground water flow model for a simplified hypothetical fresh water lens that is similar to shallow, coastal aquifers found along the Atlantic coast of the United States. Simulations of sea-level rise of 2.65 mm/year from 1929 to 2050 resulted in an increase in water levels relative to a fixed datum, yet a net decrease in water levels relative to the increased sea-level position. The net decrease in water levels was much greater near a gaining stream than farther from the stream. The difference in the change in water levels is attributed to the dampening effect of the stream on water level changes in response to sea-level rise. In response to the decreased water level altitudes relative to local sea level, the depth to the fresh water/salt water interface decreased. This reduction in the thickness of the fresh water lens varied throughout the aquifer and was greatly affected by proximity to a ground water fed stream and whether the stream was tidally influenced. Away from the stream, the thickness of the fresh water lens decreased by about 2% from 1929 to 2050, whereas the fresh water lens thickness decreased by about 22% to 31% for the same period near the stream, depending on whether the stream was tidally influenced. The difference in the change in the fresh water/salt water interface position is controlled by the difference in the net decline in water levels relative to local sea level. ?? 2007 National Ground Water Association.

  9. Determination of trace level perchlorate in drinking water and ground water by ion chromatography.

    PubMed

    Jackson, P E; Laikhtman, M; Rohrer, J S

    1999-07-30

    Ammonium perchlorate, a key ingredient in solid rocket propellants, has recently been found in ground and surface waters in the USA in a number of states, including California, Nevada, Utah, and West Virginia. Perchlorate poses a health risk and preliminary data from the US Environmental Protection Agency reports that exposure to less than 4-18 micrograms/l provides adequate human health protection. An ion chromatographic method was developed for the determination of low microgram/l levels of perchlorate in drinking and ground waters based on a Dionex IonPac AS11 column, a 100 mM hydroxide eluent, large loop (1000 microliters) injection, and suppressed conductivity detection. The method is free of interferences from common anions, linear in the range of 2.5-100 micrograms/l, and quantitative recoveries were obtained for low microgram/l levels of perchlorate in spiked drinking and ground water samples. The method detection limit of 0.3 microgram/l permits quantification of perchlorate below the levels which ensure adequate health protection. A new polarizable anion analysis column, the IonPac AS16, and its potential applicability for this analysis is also discussed.

  10. Non Invasive Water Level Monitoring on Boiling Water Reactors Using Internal Gamma Radiation: Application of Soft Computing Methods

    SciTech Connect

    Fleischer, Sebastian; Hampel, Rainer

    2006-07-01

    To provide best knowledge about safety-related water level values in boiling water reactors (BWR) is essentially for operational regime. For the water level determination hydrostatic level measurement systems are almost exclusively applied, because they stand the test over many decades in conventional and nuclear power plants (NPP). Due to the steam generation especially in BWR a specific phenomenon occurs which leads to a water-steam mixture level in the reactor annular space and reactor plenum. The mixture level is a high transient non-measurable value concerning the hydrostatic water level measuring system and it significantly differs from the measured collapsed water level. In particular, during operational and accidental transient processes like fast negative pressure transients, the monitoring of these water levels is very important. In addition to the hydrostatic water level measurement system a diverse water level measurement system for BWR should be used. A real physical diversity is given by gamma radiation distribution inside and outside the reactor pressure vessel correlating with the water level. The vertical gamma radiation distribution depends on the water level, but it is also a function of the neutron flux and the coolant recirculation pump speed. For the water level monitoring, special algorithms are required. An analytical determination of the gamma radiation distribution outside the reactor pressure vessel is impossible due to the multitude of radiation of physical processes, complicated non-stationary radiation source distribution and complex geometry of fixtures. For creating suited algorithms Soft Computing methods (Fuzzy Sets Theory, Artificial Neural Networks, etc.) will be used. Therefore, a database containing input values (gamma radiation distribution) and output values (water levels) had to be built. Here, the database was established by experiments (data from BWR and from a test setup) and simulation with the authorised thermo

  11. Hydrogeology, ground-water use, and ground-water levels in the Mill Creek Valley near Evendale, Ohio

    USGS Publications Warehouse

    Schalk, Charles; Schumann, Thomas

    2002-01-01

    Withdrawals of ground water in the central Mill Creek Valley near Evendale, Ohio, caused water-level declines of more than 100 feet by the 1950s. Since the 1950s, management practices have changed to reduce the withdrawals of ground water, and recovery of water levels in long-term monitoring wells in the valley has been documented. Changing conditions such as these prompted a survey of water use, streamflow conditions, and water levels in several aquifers in the central Mill Creek Valley, Hamilton and Butler Counties, Ohio. Geohydrologic information, water use, and water levels were compiled from historical records and collected during the regional survey. Data collected during the survey are presented in terms of updated geohydrologic information, water use in the study area, water levels in the aquifers, and interactions between ground water and surface water. Some of the data are concentrated at former Air Force Plant 36 (AFP36), which is collocated with the General Electric Aircraft Engines (GEAE) plant, and these data are used to describe geohydrology and water levels on a more local scale at and near the plant. A comparison of past and current ground-water use and levels indicates that the demand for ground water is decreasing and water levels are rising. Before 1955, most of the major industrial ground-water users had their own wells, ground water was mined from a confined surficial (lower) aquifer, and water levels were more than 100 feet below their predevelopment level. Since 1955, however, these users have been purchasing their water from the city of Cincinnati or a private water purveyor. The cities of Reading and Lockland, both producers of municipal ground-water supplies in the area, shut down their well fields within their city limits. Because the demand for ground-water supplies in the valley has lessened greatly since the 1950s, withdrawals have decreased, and, consequently, water levels in the lower aquifer are 65 to 105 feet higher than they were

  12. Water-level predictions for Indian Wells Valley ground-water basin, California, 1978

    USGS Publications Warehouse

    Mallory, Michael J.

    1979-01-01

    Ground-water pumpage in Indian Wells Valley, virtually a closed basin in the Mojave Desert of southern California, has increased gradually since 1945 and presently exceeds the long-term mean annual recharge (perennial supply). In order to aid in the understanding and management of the ground-water basin, a digital ground-water model was constructed by the U.S. Geological Survey. Since the original development of this model, conditions in the basin, including areal distribution and rates of ground-water pumpage, have changed. The results of simulation for the period 1969-76 constitute a second verification of the original model. Calculated heads for 1976 agree with the observed heads, indicating a good calibration of the original model. A predictive simulation for the period 1977-2020 used pumpage values increasing from about 15,500 acre-feet per year to about 26,000 acre-feet per year. The pumpage used in this report reflects a slightly slower growth rate and a more concentrated pattern of development than that investigated when the model was originally developed. The effects of this pattern of pumpage are reflected in the water levels simulated by the model. Predicted drawdowns for 1983 are less extensive but locally more severe than those predicted earlier. The reversal of the hydraulic gradient between China Lake playa and the city of Ridgecrest, as produced by these drawdowns by the year 2020, suggests that the water-quality effects of such drawdowns should be investigated, as this could result in inferior water from the China Lake playa area flowing southward into areas of withdrawal. (Woodard-USGS)

  13. 77 FR 25721 - Small Entity Compliance Guide: Bottled Water: Quality Standard: Establishing an Allowable Level...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-01

    ... HUMAN SERVICES Food and Drug Administration Small Entity Compliance Guide: Bottled Water: Quality... availability of a guidance for industry entitled ``Bottled Water: Quality Standard: Establishing an Allowable... its bottled water standard of quality regulations by establishing an allowable level for...

  14. THE PERSISTENCE OF MYCOBACTERIUM AVIUM IN A DRINKING WATER DISTRIBUTION SYSTEM AFTER THE ADDITION OF FILTRATION TREATMENT

    EPA Science Inventory

    There is evidence that drinking water may be a source of pathogenic nontuberculous mycobacteria (NTM) infections in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular location within protozoa. Our goal was to determ...

  15. The persistence of Mycobacterium avium in a drinking water system, what is the risk to human health?

    EPA Science Inventory

    Drinking water is believed to be a major source of human exposure to nontuberculous mycobacteria (NTM) such as Mycobacterium avium. We monitored the prevalence of M. avium in a drinking water system during the addition of filtration treatment. Our goal was to determine if the pre...

  16. Persistent Intermediate Water Warming during Cold Stadials in the SE Nordic Seas during the Last 65 Kyr

    NASA Astrophysics Data System (ADS)

    Rasmussen, T. L.; Ezat, M.; Groeneveld, J.

    2014-12-01

    In the Nordic seas, conversion of inflowing warm Atlantic surface water to deep cold water through convection is closely linked with climate. During the last glacial period climate underwent rapid millennial-scale variability known as Dansgaard-Oeschger (DO) events, consisting of warm interstadials and cold stadials. Here we present the first benthic foraminiferal Mg/Ca-d18O record from the Nordic seas in order to reconstruct the ocean circulation on DO timescales. The record confirms that modern-like convection took place in the Nordic seas during interstadials with cold bottom water temperatures (BWT) close to modern temperatures. The results show gradual and pronounced BWT increases by 2-5 °C during stadials indicating a stop or near-stop in convection. The BWT peaks are followed by an abrupt drop in temperature at the onset of interstadials indicating the abrupt start of convection and renewed generation of cold deep water. The rise in BWT during stadials confirms earlier interpretations of subsurface inflow of warm Atlantic water below a halocline reaching >1.2 km water depth. The results suggest that warm Atlantic Water never ceased to flow into the Nordic seas during the glacial period with inflow at the surface during the Holocene and warm interstadials switching to subsurface and intermediate inflow during cold stadials. Our results suggest that it is the vertical shifts in the position of the warm Atlantic Water that cause the abrupt surface warmings.

  17. THE PERSISTENCE OF NONTUBERCULOUS MYCOBACTERIA INI A DRINKING WATER DISTRIBUTION SYSTEM AFTER THE ADDITION OF FILTRATION TREATMENT

    EPA Science Inventory

    There is evidence that drinking water may be a source of pathogenic nontuberculous mycobacteria (NTM) infections in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular colonization of protozoa. Our goal was to determ...

  18. Tar balls from Deep Water Horizon oil spill: environmentally persistent free radicals (EPFR) formation during crude weathering.

    PubMed

    Kiruri, Lucy W; Dellinger, Barry; Lomnicki, Slawo

    2013-05-01

    Tar balls collected from the Gulf of Mexico shores of Louisiana and Florida after the BP oil spill have shown the presence of electron paramagnetic resonance (EPR) spectra characteristic of organic free radicals as well as transition metal ions, predominantly iron(III) and manganese(II). Two types of organic radicals were distinguished: an asphaltene radical species typically found in crude oil (g = 2.0035) and a new type of radical resulting from the environmental transformations of crude (g = 2.0041-47). Pure asphaltene radicals are resonance stabilized over a polyaromatic structure and are stable in air and unreactive. The new radicals were identified as products of partial oxidation of crude components and result from the interaction of the oxidized aromatics with metal ion centers. These radicals are similar to semiquinone-type, environmentally persistent free radicals (EPFRs) previously observed in combustion-generated particulate and contaminated soils.

  19. Tar balls from Deep Water Horizon oil spill: environmentally persistent free radicals (EPFR) formation during crude weathering.

    PubMed

    Kiruri, Lucy W; Dellinger, Barry; Lomnicki, Slawo

    2013-05-01

    Tar balls collected from the Gulf of Mexico shores of Louisiana and Florida after the BP oil spill have shown the presence of electron paramagnetic resonance (EPR) spectra characteristic of organic free radicals as well as transition metal ions, predominantly iron(III) and manganese(II). Two types of organic radicals were distinguished: an asphaltene radical species typically found in crude oil (g = 2.0035) and a new type of radical resulting from the environmental transformations of crude (g = 2.0041-47). Pure asphaltene radicals are resonance stabilized over a polyaromatic structure and are stable in air and unreactive. The new radicals were identified as products of partial oxidation of crude components and result from the interaction of the oxidized aromatics with metal ion centers. These radicals are similar to semiquinone-type, environmentally persistent free radicals (EPFRs) previously observed in combustion-generated particulate and contaminated soils. PMID:23510127

  20. Tar Balls from Deep Water Horizon Oil Spill: Environmentally Persistent Free Radicals (EPFR) Formation During Crude Weathering

    PubMed Central

    Kiruri, Lucy W.; Dellinger, Barry; Lomnicki, Slawo

    2014-01-01

    Tar balls collected from the Gulf of Mexico shores of Louisiana and Florida after the BP oil spill have shown the presence of electron paramagnetic resonance (EPR) spectra characteristic of organic free radicals as well as transition metal ions, predominantly iron(III) and manganese(II). Two types of organic radicals were distinguished: an asphaltene radical species typically found in crude oil (g = 2.0035) and a new type of radical resulting from the environmental transformations of crude (g = 2.0041−47). Pure asphaltene radicals are resonance stabilized over a polyaromatic structure and are stable in air and unreactive. The new radicals were identified as products of partial oxidation of crude components and result from the interaction of the oxidized aromatics with metal ion centers. These radicals are similar to semiquinone-type, environmentally persistent free radicals (EPFRs) previously observed in combustion-generated particulate and contaminated soils. PMID:23510127

  1. Geographical distribution of drinking-water with high iodine level and association between high iodine level in drinking-water and goitre: a Chinese national investigation.

    PubMed

    Shen, Hongmei; Liu, Shoujun; Sun, Dianjun; Zhang, Shubin; Su, Xiaohui; Shen, Yanfeng; Han, Hepeng

    2011-07-01

    Excessive iodine intake can cause thyroid function disorders as can be caused by iodine deficiency. There are many people residing in areas with high iodine levels in drinking-water in China. The main aim of the present study was to map the geographical distribution of drinking-water with high iodine level in China and to determine the relationship between high iodine level in drinking-water and goitre prevalence. Iodine in drinking-water was measured in 1978 towns of eleven provinces in China, with a total of 28,857 water samples. We randomly selected children of 8-10 years old, examined the presence of goitre and measured their urinary iodine in 299 towns of nine provinces. Of the 1978 towns studied, 488 had iodine levels between 150 and 300 μg/l in drinking-water, and in 246 towns, the iodine level was >300 μg/l. These towns are mainly distributed along the original Yellow River flood areas, the second largest river in China. Of the 56 751 children examined, goitre prevalence was 6.3 % in the areas with drinking-water iodine levels of 150-300 μg/l and 11.0 % in the areas with drinking-water iodine >300 μg/l. Goitre prevalence increased with water and urinary iodine levels. For children with urinary iodine >1500 μg/l, goitre prevalence was 3.69 times higher than that for those with urinary iodine levels of 100-199 μg/l. The present study suggests that drinking-water with high iodine levels is distributed in eleven provinces of China. Goitre becomes more prevalent with the increase in iodine level in drinking-water. Therefore, it becomes important to prevent goitre through stopping the provision of iodised salt and providing normal drinking-water iodine through pipelines in these areas in China.

  2. Ground-water levels in water year 1987 and estimated ground-water pumpage in water years 1986-87, Carson Valley, Douglas County, Nevada

    USGS Publications Warehouse

    Berger, D.L.

    1990-01-01

    Groundwater levels were measured at 58 wells during water year 1987 and a summary of estimated pumpage is given for water years 1986 and 1987 in Carson Valley, Douglas County, Nevada. The data were collected to provide a record of groundwater changes over the long-term and pumpage estimates that can be incorporated into an existing groundwater model. The estimated total pumpage in water year 1986 was 10,200 acre-ft and in water year 1987 was 13,400 acre-ft. Groundwater levels exhibited seasonal fluctuations but remained relatively stable over the reporting period throughout most of the valley. (USGS)

  3. Survey of fluoride levels in vended water stations.

    PubMed

    Jadav, Urvi G; Archarya, Bhavini S; Velasquez, Gisela M; Vance, Bradley J; Tate, Robert H; Quock, Ryan L

    2014-01-01

    This study sought to measure the fluoride concentration of water derived from vended water stations (VWS) and to identify its clinical implications, especially with regard to caries prevention and fluorosis. VWS and corresponding tap water samples were collected from 34 unique postal zip codes; samples were analyzed in duplicate for fluoride concentration. Average fluoride concentration in VWS water was significantly lower than that of tap water (P < 0.001). Fluoride concentration in the VWS water ranged from <0.01 ppm to 0.04 ppm, with a mean concentration of 0.02 ppm (±0.02 ppm). Patients utilizing VWS as their primary source of drinking water may not be receiving optimal caries preventive benefits; thus dietary fluoride supplementation may be indicated. Conversely, to minimize the risk of fluorosis in infants consuming reconstituted infant formula, water from a VWS may be used. PMID:25184716

  4. Preleukemic TEL-AML1-positive clones at cell level of 10(-3) to 10(-4) do not persist into adulthood.

    PubMed

    Olsen, Marianne; Madsen, Hans O; Hjalgrim, Henrik; Gregers, Jannie; Rostgaard, Klaus; Schmiegelow, Kjeld

    2006-11-01

    The TEL-AML1 translocation, t(12;21)(p13;q22), is one of the most frequent genetic aberrations in childhood B-cell precursor acute lymphoblastic leukemia (ALL), where it occurs in 25% of all cases. In contrast, the translocation is seen in only 3% of adult ALL cases. Evidence suggests that the TEL-AML1 translocation occurs in utero in 1% of all newborn children at cell levels of 10 to 10. In this study, we explore the prevalence of TEL-AML1-positive cells in 2 cohorts of healthy blood donors by real-time and nested reverse transcription-polymerase chain reaction. Overall, TEL-AML1-positive cells were demonstrated in 10 of 2005 healthy donors, that is, a prevalence of 0.5% (95% confidence interval, 0.2-0.3%). The level of TEL-AML1-positive cells was estimated to 10 to 10. The observed prevalence of TEL-AML1-positive cells in healthy adults is of the same order of magnitude as the prevalence reported in healthy newborns, but the observed cell level of 10 to 10 is much lower. These data indicates that prenatal TEL-AML1 subclones does not persist throughout adult life at cell levels of 10 to 10. The findings are compatible with the risk of t(12;21)(p13;q22) ALL correlating with the total number of TEL-AML1-positive cells in peripheral blood in both childhood and adulthood. PMID:17114960

  5. REDUCING ARSENIC LEVELS IN DRINKING WATER: APPROACHES AND CONSIDERATIONS

    EPA Science Inventory

    The recently promulgated Arsenic Rule will require that many new drinking water systems treat their water to remove arsenic. It has been projected that the State of Ohio will have nearly 140 community and non-community non-transient water systems in violation of the Rule. This ...

  6. Wave transformation and shoreline water level on Funafuti Atoll, Tuvalu

    NASA Astrophysics Data System (ADS)

    Beetham, Edward; Kench, Paul S.; O'Callaghan, Joanne; Popinet, Stéphane

    2016-01-01

    The influence of sea swell (SS) waves, infragravity (IG) waves, and wave setup on maximum runup (Rmax) is investigated across different tidal stages on Fatato Island, Funafuti Atoll, Tuvalu. Field results illustrate that SS waves are tidally modulated at the shoreline, with comparatively greater wave attenuation and setup occurring at low tide versus high tide. A shoreward increase in IG wave height is observed across the 100 m wide reef flat at all tidal elevations, with no tidal modulation of IG wave height at the reef flat or island shoreline. A 1-D shock-capturing Green-Naghdi solver is used to replicate the field deployment and analyze Rmax. Model outputs for SS wave height, IG wave height and setup at the shoreline match field results with model skill >0.96. Model outputs for Rmax are used to identify the temporal window when geomorphic activity can occur on the beach face. During periods of moderate swell energy, waves can impact the beach face at spring low tide, due to a combination of wave setup and strong IG wave activity. Under mean wave conditions, the combined influence of setup, IG waves and SS waves results in interaction with island sediment at midtide. At high tide, SS and IG waves directly impact the beach face. Overall, wave activity is present on the beach face for 71% of the study period, a significantly longer duration than is calculated using mean water level and topographic data.

  7. Ground-water monitoring at Santa Barbara, California; Phase 2, Effects of pumping on water levels and on water quality in the Santa Barbara ground-water basin

    USGS Publications Warehouse

    Martin, Peter

    1984-01-01

    From July 1978 to January 1980, water levels in the southern part of the Santa Barbara ground-water basin declined more than 100 feet. These water-level declines resulted from increases in municipal pumping since July 1978. The increase in municipal pumping was part of a basin-testing program designed to determine the usable quantity of ground water in storage. The pumping, centered in the city less than 1 mile from the coast, has caused water-level declines to altitudes below sea level in the main water-bearing zones. As a result, the ground-water basin would be subject to saltwater intrusion if the study-period pumpage were maintained or increased. Data indicate that saltwater intrusion has degraded the quality of the water yielded from six coastal wells. During the study period, the six coastal wells all yielded water with chloride concentrations in excess of 250 milligrams per liter, and four of the wells yielded water with chloride concentrations in excess of 1,000 milligrams per liter. Previous investigators believed that saltwater intrusion was limited to the shallow part of the aquifer, directly adjacent to the coast. The possibility of saltwater intrusion into the deeper water-bearing deposits in the aquifer was thought to be remote because an offshore fault truncates these deeper deposits so that they lie against consolidated rocks on the seaward side of the fault. Results of this study indicate, however, that ocean water has intruded the deeper water-bearing deposits, and to a much greater extent than in the shallow part of the aquifer. Apparently the offshore fault is not an effective barrier to saltwater intrusion. No physical barriers are known to exist between the coast and the municipal well field. Therefore, if the pumping rate maintained during the basin-testing program were continued, the degraded water along the coast could move inland and contaminate the municipal supply wells. The time required for the degraded water to move from the coast to

  8. Estimating Impaired Waters on a County Level for Public Health Analysis

    EPA Science Inventory

    Assessing the population-level impact of water quality on health can be difficult. Water quality data are measured at a watershed level and health data are organized at different levels of aggregation. To address this discrepancy and enable the consideration of water quality for ...

  9. Environmental assessment of drainage water impacts on water quality and eutrophication level of Lake Idku, Egypt.

    PubMed

    Ali, Elham M; Khairy, Hanan M

    2016-09-01

    Lake Idku, northern Egypt, receives large quantities of drainage water from four main discharging drains. Ecological and biological status of Lake Idku has been monitored during (autumn 2012 to summer 2013) to examine the lake water quality and eutrophication level in response to the quality as well as the source of the discharging water. Discrete water samples were collected from the lake body and the drains. Chemical analyses revealed an excessive nutrient load goes into the lake. A range of 1.4-10.6 mg nitrites/L was determined for drain waters, however a sudden increase was observed in lake and drain water samples of up to 84 and 74.5 mg/L, respectively. Reactive silicate ranged between 2.9 and 4.8 mg/L; while inorganic phosphate fluctuated between 0.2 and 0.43 mg/L. Transparency varied from 45 cm to 134 cm with better light conditions at drain sites. Biological results indicated a hyper-eutrophic status for the lake with a range of chlorophyll-a varied from a minimum of 39.9 μg/L (at Idku Drains) and a maximum of 104.2 μg/L (at El-Khairy drain). Phytoplankton community structure revealed higher abundance at lake sites compared with the drains. Maximum phytoplankton density was detected during summer with the dominance of Bacilariophyceae (e.g. Cyclotella meneghiniana, Cyclotella comate, Melosira varians) followed by Chlorophycean taxon (e.g. Scenedesmus dimorphus, S. bijuga and Crucigenia tetrapedia). Five indices were applied to evaluate the water quality of the lake. Diversity Index (DI) indicated slight to light pollution along all sites; while Sapropic Index (SI) indicated slight pollution with acceptable oxygen conditions and an availability of sensitive species. Palmer Index (PI) gave a strong evidence of high organic pollution at some sites in the lake, while Generic Diatom Index (GDI) revealed that levels of pollution varied from average to strong. Trophic Index (TI), suggest that there are an obvious signs of eutrophication in the lake. PMID

  10. Roof water collection systems in some Southeast Asian countries: status and water quality levels.

    PubMed

    Appan, A

    1997-10-01

    There is extensive use of simple and inexpensive roof water collection systems in some Southeast Asian countries. The collected runoff which flows off different types of roofs is affected not only by the inherent quality of the roofing material but also by the contamination of roofs by rodents, birds, etc. Consequently, bacteriological quality levels are excessive though the collected rainwater is still used extensively for potable purposes. From samples collected in most locations, there were positive Total and Faecal Coliform counts though, in terms of physico-chemical parameters, roof water appears to be of a higher quality. Various causes have been attributed to the frequent presence of Faecal Coliform but, mostly, pollution is of animal origin as the Faecal Coliform/Faecal Streptococci ratio is less than unity. It is proposed that the collected roof water be boiled, disinfected with household bleach or be subjected to radiation from sunlight which appears to have good potential to be an effective bactericide. It is recommended that simple testing methods be developed and health education imparted to the various aspects of utilising roof water collection systems.

  11. Ground-water levels and directions of flow in Geauga County, Ohio, September 1994, and changes in ground-water levels, 1986-94

    USGS Publications Warehouse

    Jagucki, M.L.; Lesney, L.L.

    1995-01-01

    This report presents the results of a study by the U.S. Geological Survey, in cooperation with Geauga County Planning Commission and Board of County Commissioners, to determine directions of ground-water flow and to assess differences from 1986 to 1994 in ground-water levels in the glacial deposits and Pottsville Formation, Cuyahoga Group, and the Berea Sandstone. Water levels were measured in 219 wells in Geauga County, Ohio, in September 1994. Water levels measured in January and February 1986 in 88 of the 219 wells were used for comparison. Water-level maps constructed from measurements made in September 1994 to show that ground-water levels in the Pottsville Formation and the glacial deposits generally correspond to the land-surface configuration and that ground water flows from the uplands to adjacent streams and buried valleys. Ground-water flow in the Cuyahoga Group is generally downward from the Pottsville Formation to the Berea Sandstone. Directions of ground-water flow in the Berea Sandstone are toward outcrop areas at the north and east edges of Geauga County and toward sub-crops beneath buried glacial valley deposits in Chardon, Chester, Munson, and Russel Townships and along the west edge of the county. A comparison of water level measurements in 1986 and 1994 indicates that water levels declined in 70 percent of the measured wells and increased in 30 percent. The change in water levels from 1986 to 1994 ranged from an increase of 13.58 feet to a decrease of 29.25 feet. Thirty percent of all water-level changes were less than 1 foot in magnitude. In nearly 80 percent of the wells, water-level changes were within the range of plus or minus 5 feet. Among the wells for which two or more historical measurements were available, the 1994 water levels in 54 percent were outside the range of water-levels observed in previous studies (only 24 percent were greater than 1 foot outside of the previously-observed range). Water-level declines of greater than 10 feet

  12. Regional water table (2004) and water-level changes in the Mojave River and Morongo ground-water basins, Southwestern Mojave Desert, California

    USGS Publications Warehouse

    Stamos, Christina L.; Huff, Julia A.; Predmore, Steven K.; Clark, Dennis A.

    2004-01-01

    The Mojave River and Morongo ground-water basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a major part of the water requirements for the region. The continuous population growth in this area has resulted in ever-increasing demands on local ground-water resources. The collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water flow systems, and consequently, water availability. During March and April 2004, the U.S. Geological Survey and other agencies made almost 900 water-level measurements in about 740 wells in the Mojave River and Morongo ground-water basins. These data document recent conditions and, when compared with historical data, changes in ground-water levels. A water-level contour map was drawn using data from 500 wells, providing coverage for most of the basins. In addition, 26 long-term (as much as 74 years) hydrographs were constructed which show water-level conditions throughout the basins, 9 short-term (1992 to 2004) hydrographs were constructed which show the effects of recharge and discharge along the Mojave River, and a water-level-change map was compiled to compare 2002 and 2004 water levels throughout the basins. The water-level change data show that in the Mojave River ground-water basin, more than one half (102) of the wells had water-level declines of 0.5 ft or more and almost one fifth (32) of the wells had declines greater than 5 ft. between 2002 and 2004. The water-level change data also show that about one tenth (17) of the wells compared in the Mojave River ground-water basin had water level increases of 0.5 ft or more. Most of the water-level increases were the result of stormflow in the Mojave River during March 2004, which resulted in recharge to wells in the floodplain aquifer mainly along the river in the Alto subarea and the Transition zone, and along the

  13. Persistent organic pollutants in chinook salmon (Oncorhynchus tshawytscha): implications for resident killer whales of British Columbia and adjacent waters.

    PubMed

    Cullon, Donna L; Yunker, Mark B; Alleyne, Carl; Dangerfield, Neil J; O'Neill, Sandra; Whiticar, Michael J; Ross, Peter S

    2009-01-01

    We measured persistent organic pollutant (POP) concentrations in chinook salmon (Oncorhynchus tshawytscha) in order to characterize dietary exposure in the highly contaminated, salmon-eating northeastern Pacific resident killer whales. We estimate that 97 to 99% of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dichlorodiphenyltrichloroethane (DDT), and hexachlorocyclohexane (HCH) in returning adult chinook were acquired during their time at sea. Highest POP concentrations (including PCBs, PCDDs, PCDFs, and DDT) and lowest lipids were observed in the more southerly chinook sampled. While feeding by salmon as they enter some more POP-contaminated near-shore environments inevitably contribute to their contamination, relationships observed between POP patterns and both lipid content and delta13C also suggest a migration-related metabolism and loss of the less-chlorinated PCB congeners. This has implications for killer whales, with the more PCB-contaminated salmon stocks in the south partly explaining the 4.0 to 6.6 times higher estimated daily intake for sigmaPCBs in southern resident killer whales compared to northern residents. We hypothesize that the lower lipid content of southerly chinook stocks may cause southern resident killer whales to increase their salmon consumption by as much as 50%, which would further increase their exposure to POPs.

  14. Persistent organic pollutants associated to water fluxes and sedimentary processes in the Colorado River delta, Baja California, México.

    PubMed

    Lugo-Ibarra, K C; Daesslé, L W; Macías-Zamora, J V; Ramírez-Álvarez, N

    2011-09-01

    Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were studied in sediment cores from two distinctive modern channels of the Colorado River (CR) delta. Their abundance and temporal changes are associated with flood-flows from the CR across the USA-Mexico border. The CR channel is directly exposed to river flood-flows while the Hardy River (HR) is a local channel derived mainly from agricultural runoff, geothermal effluents, and treated urban wastewater. Different headwater compositions and degrees of exposure to flood-flows appear to be the factors controlling the composition of persistent organic pollutants (POPs). Enrichment of OCPs (46 ng g(-1) dwt in HR and 4.37 ng g(-1) dwt in CR) occurred during or a few years after flooding. PCB-138 (4.2 ng g(-1)dwt) is enriched in HR suggesting its origin in dielectric oils from the geothermal power plant. PCB-28 (2.1 ng g(-1)dwt) in CR may be related with atmospheric input and/or re-deposition of upstream sediments. In surficial sediments (0-3 cm), only HR exceeds international sediment quality guidelines (4,4'-DDE=8.16 ng g(-1)dwt and ΣDDT=8.34 ng g(-1)dwt).

  15. Borehole sounding device with sealed depth and water level sensors

    DOEpatents

    Skalski, Joseph C.; Henke, Michael D.

    2005-08-02

    A borehole device having proximal and distal ends comprises an enclosure at the proximal end for accepting an aircraft cable containing a plurality of insulated conductors from a remote position. A water sensing enclosure is sealingly attached to the enclosure and contains means for detecting water, and sending a signal on the cable to the remote position indicating water has been detected. A bottom sensing enclosure is sealingly attached to the water sensing enclosure for determining when the borehole device encounters borehole bottom and sends a signal on the cable to the remote position indicating that borehole bottom has been encountered.

  16. Water-level map of the Mississippi delta alluvium in northwestern Mississippi, April 1981

    USGS Publications Warehouse

    Darden, Daphne

    1981-01-01

    Water levels were measured in 454 wells in the alluvial sediments in northwestern Mississippi during the period April 13-24, 1981. Ground-water levels are higher after winter and spring rains and lower after heavy agricultural and industrial pumping. Locally, water levels fluctuate as rivers and streams fluctuate. Because of the drought conditions in April 1981, most water wells had risen several feet. In some areas, however, water levels had not recovered from the relatively low levels measured in September 1980. (USGS)

  17. Water Levels In Major Artesian Aquifers Of The New Jersey Coastal Plain, 1988

    USGS Publications Warehouse

    Rosman, Robert; Lacombe, Pierre J.; Storck, Donald A.

    1995-01-01

    Water levels in 1,251 wells in the New Jersey Coastal Plain, Philadelphia County, Pennsylvania, and Kent and New Castle Counties, Delaware, were measured from October 1988 to February 1989 and compared with 1,071 water levels measured from September 1983 to May 1984. Water levels in 916 of the wells measured in the 1983 study were remeasured in the 1988 study. Alternate wells were selected to replace wells used in 1983 that were inaccessible at the time of the water-level measurements in 1988 or had been destroyed. New well sites were added in strategic locations to increase coverage where possible. Large cones of depression have formed or expanded in the nine major artesian aquifers that underlie the New Jersey Coastal Plain. Water levels are shown on nine potentiometric-surface maps. Hydrographs for observation wells typically show water-level declines for 1983, through 1989. In the confined Cohansey aquifer, the lowest water level, 20 feet below sea level, was measured in a well located at Cape May City Water Department, Cape May County. Water levels in the Atlantic City 800-foot sand declined as much as 21 feet at Ventnor, Atlantic County, over the 6-year period from the 1983 study to this study for 1988. Water levels in the Piney Point aquifer were as low as 56 feet below sea level at Seaside Park, Ocean County; 45 feet below sea level in southern Cumberland County; and 28 feet below sea level at Margate, Atlantic County. Water levels in the Vincentown aquifer did not change over the 6-year period. The lowest water levels in the Wenonah-Mount Laurel aquifer and the Englishtown aquifer system were 218 feet and 256 feet below sea level, respectively. Large cones of depression in the Potomac- Raritan-Magothy aquifer system are centered in the Camden County area and the Middlesex and Monmouth County area. Water levels declined as much as 46 feet in these areas over the 6-year period.

  18. Association between Arsenic Exposure from Drinking Water and Plasma Levels of Soluble Cell Adhesion Molecules

    PubMed Central

    Chen, Yu; Santella, Regina M.; Kibriya, Muhammad G.; Wang, Qiao; Kappil, Maya; Verret, Wendy J.; Graziano, Joseph H.; Ahsan, Habibul

    2007-01-01

    Background Epidemiologic studies of cardiovascular disease risk factors and appropriate biomarkers in populations exposed to a wide range of arsenic levels are a public health research priority. Objective We investigated the relationship between inorganic arsenic exposure from drinking water and plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular adhesion molecule-1 (sVCAM-1), both markers of endothelial dysfunction and vascular inflammation, in an arsenic-exposed population in Araihazar, Bangladesh. Methods The study participants included 115 individuals with arsenic-related skin lesions participating in a 2 × 2 randomized, placebo-controlled, double-blind trial of vitamin E and selenium supplementation. Arsenic exposure status and plasma levels of sICAM-1 and sVCAM-1 were assessed at baseline and after 6 months of follow-up. Results Baseline well arsenic, a long-term measure of arsenic exposure, was positively associated with baseline levels of both sICAM-1 and sVCAM-1 and with changes in the two markers over time. At baseline, for every 1-μg/L increase in well arsenic there was an increase of 0.10 ng/mL [95% confidence interval (CI), 0.00–0.20] and 0.33 ng/mL (95% CI, 0.15–0.51) in plasma sICAM-1 and sVCAM-1, respectively. Every 1-μg/L increase in well arsenic was associated with a rise of 0.11 ng/mL (95% CI, 0.01–0.22) and 0.17 ng/mL (95% CI, 0.00–0.35) in sICAM-1 and sVCAM-1 from baseline to follow-up, respectively, in spite of recent changes in urinary arsenic as well as vitamin E and selenium supplementation during the study period. Conclusions The findings indicate an effect of chronic arsenic exposure from drinking water on vascular inflammation that persists over time and also suggest a potential mechanism underlying the association between arsenic exposure and cardiovascular disease. PMID:17938729

  19. Lake Storage Measurements For Water Resources Management: Combining Remotely Sensed Water Levels and Surface Areas

    NASA Astrophysics Data System (ADS)

    Brakenridge, G. R.; Birkett, C. M.

    2013-12-01

    Presently operating satellite-based radar altimeters have the ability to monitor variations in surface water height for large lakes and reservoirs, and future sensors will expand observational capabilities to many smaller water bodies. Such remote sensing provides objective, independent information where in situ data are lacking or access is restricted. A USDA/NASA (http://www.pecad.fas.usda.gov/cropexplorer/global_reservoir/) program is performing operational altimetric monitoring of the largest lakes and reservoirs around the world using data from the NASA/CNES, NRL, and ESA missions. Public lake-level products from the Global Reservoir and Lake Monitor (GRLM) are a combination of archived and near real time information. The USDA/FAS utilizes the products for assessing international irrigation potential and for crop production estimates; other end-users study climate trends, observe anthropogenic effects, and/or are are involved in other water resources management and regional water security issues. At the same time, the Dartmouth Flood Observatory (http://floodobservatory.colorado.edu/), its NASA GSFC partners (http://oas.gsfc.nasa.gov/floodmap/home.html), and associated MODIS data and automated processing algorithms are providing public access to a growing GIS record of the Earth's changing surface water extent, including changes related to floods and droughts. The Observatory's web site also provide both archival and near real time information, and is based mainly on the highest spatial resolution (250 m) MODIS bands. Therefore, it is now possible to provide on an international basis reservoir and lake storage change measurements entirely from remote sensing, on a frequently updating basis. The volume change values are based on standard numerical procedures used for many decades for analysis of coeval lake area and height data. We provide first results of this combination, including prototype displays for public access and data retrieval of water storage

  20. Water levels in continuously monitored wells in the Yucca Mountain area, Nevada, 1985--88

    SciTech Connect

    Luckey, R.R.; Lobmeyer, D.H.; Burkhardt, D.J.

    1993-07-01

    Water levels have been monitored hourly in 15 wells completed in 23 depth intervals in the Yucca Mountain area, Nevada. Water levels were monitored using pressure transducers and were recorded by data loggers. The pressure transducers were periodically calibrated by raising and lowering them in the wells. The water levels were normally measured at approximately the same time that the transducers were calibrated. Where the transducer output appeared reasonable, it was converted to water levels using the calibrations and manual water- level measurements. The amount of transducer output that was converted to water levels ranged from zero for several intervals to about 98 percent for one interval. Fourteen of the wells were completed in Tertiary volcanic rocks and one well was completed in Paleozoic carbonate rocks. Each well monitored from one to four depth intervals. Water-level fluctuation caused by barometric pressure changes and earth tides were observed.

  1. Muscle alkali-soluble protein, carnitine, water and electrolytes in patients with persistent post-operative infection.

    PubMed

    Soop, M; Forsberg, E; Thörne, A; Cederblad, G; Bergström, J; Forsberg, A M; Hultman, E

    1989-10-01

    The muscle contents of water, electrolytes, creatine, alkali-soluble protein (ASP) and carnitine were determined using percutaneous muscle biopsy technique. Seven patients with prolonged catabolic states and subsequent respiratory failure were studied. Twelve age- and sex-matched healthy subjects were used for comparison. The muscle content of alkali-soluble protein in relation to the content of DNA was less than half of control values, indicating a loss of more than 50% of muscle protein content. The muscle carnitine content was 25.9 +/- 6.5 mumol/g alkali-soluble protein, suggesting a preserved muscle carnitine concentration. Total muscle water was increased by over 20%, mainly due to an increase in extracellular water. Muscle sodium and chloride contents were doubled. The content of magnesium was slightly reduced but muscle potassium was normal. The marked depletion of muscle protein may have contributed to the requirements for artificial ventilation and the difficulties in weaning off the ventilator. The increase in muscle water masks the loss of metabolically active muscle tissue yielding low values for energy expenditure when relating to body weight. The benefit of the use of the ASP/DNA ratio in nutritional assessment is emphasised.

  2. Phi 6 and Phi 8 as Potential Surrogates for Avian Influenza Viruses in Persistence Studies in Water-Abstract

    EPA Science Inventory

    Wild aquatic birds are the natural reservoir for avian influenza viruses, and water is known to play an important role in the transmission of virus within this reservoir system. Despite its recognized importance, we have very little understanding of what factors enhance or limit...

  3. Phi 6 and Phi 8 as Potential Surrogates for Avian Influenza Viruses in Persistence Studies in Water - Poster

    EPA Science Inventory

    Wild aquatic birds are the natural reservoir for avian influenza viruses, and water is known to play an important role in the transmission of virus within this reservoir system. Despite its recognized importance, we have very little understanding of what factors enhance or limit...

  4. Options for water-level control in developed wetlands

    USGS Publications Warehouse

    Kelley, J. R.; Laubhan, M. K.; Reid, F. A.; Wortham, J. S.; Fredrickson, L. H.

    1993-01-01

    Wetland habitats in the United States currently are lost at a rate of 260,000 acres/year (105,218 ha/year). Consequently, water birds concentrate in fewer and smaller areas. Such concentrations may deplete food supplies and influence behavior, physiology, and survival. Continued losses increase the importance of sound management of the remaining wetlands because water birds depend on them. Human activities modified the natural hydrology of most remaining wetlands in the conterminous United States, and such hydrologic alterations frequently reduce wetland productivity. The restoration of original wetland functions and productivity often requires the development of water distribution and discharge systems to emulate natural hydrologic regimes. Construction of levees and correct placement of control structures and water-delivery and water-discharge systems are necessary to (1) create soil and water conditions for the germination of desirable plants, (2) control nuisance vegetation, (3) promote the production of invertebrates, and (4) make foods available for wildlife that depends of wetlands (Leaflets 13.2.1 and 13.4.6). This paper provides basic guidelines for the design of wetlands that benefit wildlife. If biological considerations are not incorporated into such designs, the capability of managing wetlands for water birds is reduced and costs often are greater. Although we address the development of palustrine wetlands in migration and wintering areas, many of the discussed principles are applicable to the development of other wetland types and in other locations.

  5. Molecular level water and solute transport in reverse osmosis membranes

    NASA Astrophysics Data System (ADS)

    Lueptow, Richard M.; Shen, Meng; Keten, Sinan

    2015-11-01

    The water permeability and rejection characteristics of six solutes, methanol, ethanol, 2-propanol, urea, Na+, and Cl-, were studied for a polymeric reverse osmosis (RO) membrane using non-equilibrium molecular dynamics simulations. Results indicate that water flux increases with an increasing fraction of percolated free volume in the membrane polymer structure. Solute molecules display Brownian motion and hop from pore to pore as they pass through the membrane. The solute rejection depends on both the size of the solute molecule and the chemical interaction of the solute with water and the membrane. When the open spaces in the polymeric structure are such that solutes have to shed at least one water molecule from their solvation shell to pass through the membrane molecular structure, the water-solute pair interaction energy governs solute rejection. Organic solutes more easily shed water molecules than ions to more readily pass through the membrane. Hydrogen-bonding sites for molecules like urea also lead to a higher rejection. These findings underline the importance of the solute's solvation shell and solute-water-membrane chemistry in solute transport and rejection in RO membranes. Funded by the Institute for Sustainability and Energy at Northwestern with computing resources from XSEDE (NSF grant ACI-1053575).

  6. Regional Water Table (2002) and Water-Level Changes in the Mojave River and Morongo Ground-Water Basins, Southwestern Mojave Desert, California

    USGS Publications Warehouse

    Smith, Gregory A.; Stamos, Christina L.; Predmore, Steven K.

    2004-01-01

    The Mojave River and Morongo ground-water basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a major part of the water requirements for the region. The continuous population growth in this area has resulted in ever-increasing demands on local ground-water resources. The collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water flow systems, and consequently, water availability. During 2002, the U.S. Geological Survey and other agencies made approximately 2,500 water-level measurements in the Mojave River and Morongo ground-water basins. These data document recent conditions and, when compared with previous data, changes in ground-water levels. A water-level contour map was drawn using data from about 600 wells, providing coverage for most of the basins. Twenty-eight hydrographs show long-term (up to 70 years) water-level conditions throughout the basins, and 9 short-term (1997 to 2002) hydrographs show the effects of recharge and discharge along the Mojave River. In addition, a water-level-change map was compiled to compare 2000 and 2002 water levels throughout the basins. In the Mojave River ground-water basin, about 66 percent of the wells had water-level declines of 0.5 ft or more since 2000 and about 27 percent of the wells had water-level declines greater than 5 ft. The only area that had water-level increases greater than 5 ft that were not attributed to fluctuations in nearby pumpage was in the Harper Lake (dry) area where there has been a significant reduction in pumpage during the last decade. In the Morongo ground-water basin, about 36 percent of the wells had water-level declines of 0.5 ft or more and about 10 percent of the wells had water-level declines greater than 5 ft. Water-level increases greater than 5 ft were measured only in the Warren subbasin, where artificial

  7. Relative effects of educational level and occupational social class on body concentrations of persistent organic pollutants in a representative sample of the general population of Catalonia, Spain.

    PubMed

    Gasull, Magda; Pumarega, José; Rovira, Gemma; López, Tomàs; Alguacil, Juan; Porta, Miquel

    2013-10-01

    Scant evidence is available worldwide on the relative influence of occupational social class and educational level on body concentrations of persistent organic pollutants (POPs) in the general population. The objective was to analyse such influence in a representative sample of the general population of Catalonia, Spain. Participants in the Catalan Health Interview Survey aged 18-74 were interviewed face-to-face, gave blood, and underwent a physical exam. The role of age, body mass index (BMI), and parity was analysed with General Linear Models, and adjusted geometric means (GMs) were obtained. Crude (unadjusted) concentrations were higher in women and men with lower education, and in women, but not men, in the less affluent social class. After adjusting for age, in women there were no associations between POP levels and social class or education. After adjusting for age and BMI, men in the less affluent class had higher p,p'-DDE concentrations than men in class I (p-value=0.016), while men in class IV had lower HCB than men in the upper class (p-value<0.03). Also in contrast with some expectations, positive associations between education and POP levels were observed after adjusting for age and BMI in men; e.g., men with university studies had higher HCB concentrations than men with first stage of primary schooling (adjusted GM 153.9 and 80.5ng/g, respectively) (p-value<0.001). When education and social class were co-adjusted for, some positive associations with education in men remained statistically significant, whereas class remained associated only with p,p'-DDE. Educational level influenced blood concentrations of POPs more than occupational social class, especially in men. In women, POP concentrations were mainly explained by age/birth cohort, parity and BMI. In men, while concentrations were also mainly explained by age/birth cohort and BMI, both social class and education showed positive associations. Important characteristics of socioeconomic groups as age

  8. Regional Water Table (1998) and Ground-Water-Level Changes in the Mojave River, and the Morongo Ground-Water Basins, San Bernardino County, California

    USGS Publications Warehouse

    Smith, Gregory A.; Pimentel, M. Isabel

    2000-01-01

    The Mojave River and the Morongo ground-water basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a major part of the water requirements for the region. The rapid and continuous population growth in this area has resulted in ever-increasing demands on local ground-water resources. The continuing collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water systems and, consequently, water availability. During 1998 the U.S. Geological Survey and other agencies made approximately 2,370 water-level measurements in the Mojave River and the Morongo ground-water basins. These data document recent conditions and changes in ground-water levels. A water-level contour map was drawn using data from 450 wells, providing coverage for most of both basins. Twenty-three hydrographs show long-term (as much as 70 years) water-level trends throughout the basins. To help show effects of late seasonal recharge along the Mojave River, 14 short-term (13 years) hydrographs were created. A water-level change map was compiled to enable comparison of 1996 and 1998 water levels. The Mojave River and the Morongo ground-water basins had little change in water levels between 1996 and 1998 - with the exception of the areas of the Yucca Valley affected by artificial recharge. Other water-level changes were localized and reflected pumping or measurements made before seasonal recharge. Three areas of perched ground water were identified: El Mirage Lake (dry), Adelanto, and Lucerne Valley.

  9. Statistical summaries of ground-water level data collected in the Suwannee River Water Management District, 1948 to 1994

    USGS Publications Warehouse

    Collins, J.J.; Freeman, L.D.

    1996-01-01

    Since 1948, ground-water level data have beensystematically collected from selected wells in theSuwannee River Water Management District (SRWMD) by the U.S. Geological Survey (USGS),the SRWMD, and other agencies. Records of waterlevels in the SRWMD (fig. 1), collected by the USGS and SRWMD through 1990, and by the SRWMD from 1990 to 1994, have been published for many years in the USGS annual report series "Water Resources Data for Florida." However, no systematic statistical summaries of water levels in the SRWMD have been previously published. The need for such statistical summary data forevaluations of drought severity, ground-water supplyavailability, and minimum water levels for regulatory purposes increases daily as demands for ground-water usage increase. Also, much of the base flow of the Suwannee River is dependent upon ground water. As the population and demand for ground water for drinking water and irrigation purposes increase, the ability to quickly and easily predict trends in ground-water availability will become paramount. In response to this need, the USGS, in cooperation with the SRWMD, compiled this report. Ground-water sta tistics for 136 sites are presented as well as figures showing water levels that were measured in wells from 1948 through September 1994. In 1994, the SRWMD and the USGS began a long- term program of cooperative studies designed tobetter understand minimum and maximum streamflows and ground-water levels in the SRWMD. Minimum and maximum flows and levels are needed by the district to manage the surface- and ground-water resources of the SRWMD and to maintain or improve the various ecosystems. Data evaluation was a necessary first step in the long- term SRWMD ground-water investigations program, because basic statistics for ground-water levels are not included in the USGS annual data reports such as "Water Resources Data for Florida, Water Year 1994" (Fran klin and others, 1995). Statistics included in this report were generated

  10. 76 FR 64810 - Beverages: Bottled Water Quality Standard; Establishing an Allowable Level for di(2-ethylhexyl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-19

    ... FR 41612), FDA published a proposal (``the 1993 proposed rule'') to revise the bottled water quality... adopting the allowable level for DEHP in the bottled water quality standard as proposed (58 FR 41612... be found in bottled water in levels above the standard. C. Benefits In the Economic Impact...

  11. Sources of Elevated Sodium Levels in Drinking Water...and Recommendations for Reduction.

    ERIC Educational Resources Information Center

    Calabrese, Edward J.; Tuthill, Robert W.

    1978-01-01

    Sodium enters drinking water by a variety of human activities and by natural means. Evidence suggests elevated levels of sodium in drinking water may adversely affect health. Action should be taken to reduce the level of human exposure to sodium in drinking water. (RE)

  12. Hydrology and water quality of Shell Lake, Washburn County, Wisconsin, with special emphasis on the effects of diversion and changes in water level on the water quality of a shallow terminal lake

    USGS Publications Warehouse

    Juckem, Paul F.; Robertson, Dale M.

    2013-01-01

    quality to changes in phosphorus inputs were evaluated by means of eutrophication models. During 2009, the total input of phosphorus to Shell Lake was 1,730 pounds (lb), of which 1,320 lb came from external sources (76 percent) and 414 lb came from internal loading from sediments in the lake (24 percent). The largest external source was from surface-water runoff, which delivered about 52 percent of the total phosphorus load compared with about 13 percent of the water input. The second largest source was from precipitation (wetfall and dryfall), which delivered 19 percent of the load compared to about 83 percent of the water input. Contributions from septic systems and groundwater accounted for about 3 and 2 percent, respectively. Increased runoff raises water levels in the lake but does not necessarily increase phosphorus loading because phosphorus concentrations in the tributaries decline during increased flow, possibly because of shorter retention times in upstream wetlands. Phosphorus loading to the lake in 2009 represented what occurred after a series of dry years; therefore, this information was combined with data from 2011, a wet year, to estimate phosphorus loading during a range of hydrologic conditions by estimating loading from each component of the phosphorus budget for each year from 1949 to 2011. Comparisons of historical water-quality records with historical water levels and applications of a hydrodynamic model (Dynamic Lake Model, DLM) and empirical eutrophication models were used to understand how changes in water level and the coinciding changes in phosphorus loading affect the water quality of Shell Lake. DLM simulations indicate that large changes in water level (approximately 10 ft) affect the persistence of stratification in the lake. During periods with low water levels, the lake is a well-mixed, polymictic system, with water quality degrading slightly as summer progresses. During periods with high water levels, the lake is more stratified, and

  13. Water-level changes and directions of ground-water flow in the shallow aquifer, Fallon area, Churchill County, Nevada

    USGS Publications Warehouse

    Seiler, R.L.; Allander, K.K.

    1993-01-01

    The Truckee-Carson-Pyramid Lake Water Rights Settlement Act of 1990 directed the U.S. Fish and Wildlife Service to acquire water rights for wetland areas in the Carson Desert, Nevada. The public is concerned that htis acquisition of water rights and delivery of the water directly to wildlife areas would result in less recharge to the shallow ground water in the Fallon area and cause domestic wells to go dry. In January 1992, the U.S. Geological Survey, in cooperation with U.S. Fish and Wildlife Service, began a study of the shallow ground-water system in the Fallon area in Churchill County, Nevada. A network of 126 wells in the study area was monitored. Between January and November 1992, water levels in most wells declined, usually less than 2 feet. The maximum measured decline over this period was 2.68 feet in a well near Stillwater Marsh. Between April and July, however, water levels rose in irrigated areas, typically 1 to 2 feet. Newlands Project water deliveries to the study area began soon after the turn of the century. Since then, water levels have risen more than 15 feet across much of the study area. Water lost from unlined irrigtiaon canals caused the stage in Big Soda Lake to rise nearly 60 feet; ground-water levels near the lake have risen 30 to 40 feet. The depth to water in most irrigated areas is now less than 10 feet. The altitude of the water table ranges from 4.025 feet above sea level 11 miles west of Fallon to 3,865 feet in the Stillwater Marsh area. Ground water flows eastward and divides; some flow goes to the northeast toward the Carson Sink and Stillwater areas, and some goes southeastward to Carson Lake.

  14. Hurricane effects on a shallow lake ecosystem and its response to a controlled manipulation of water level.

    PubMed

    Havens, K E; Jin, K R; Rodusky, A J; Sharfstein, B; Brady, M A; East, T L; Iricanin, N; James, R T; Harwell, M C; Steinman, A D

    2001-04-01

    In order to reverse the damage to aquatic plant communities caused by multiple years of high water levels in Lake Okeechobee, Florida (U.S.), the Governing Board of the South Florida Water Management District (SFWMD) authorized a "managed recession" to substantially lower the surface elevation of the lake in spring 2000. The operation was intended to achieve lower water levels for at least 8 weeks during the summer growing season, and was predicted to result in a large-scale recovery of submerged vascular plants. We treated this operation as a whole ecosystem experiment, and assessed ecological responses using data from an existing network of water quality and submerged plant monitoring sites. As a result of large-scale discharges of water from the lake, coupled with losses to evaporation and to water supply deliveries to agriculture and other regional users, the lake surface elevation receded by approximately 1 m between April and June. Water depths in shoreline areas that historically supported submerged plant communities declined from near 1.5 m to below 0.5 m. Low water levels persisted for the entire summer. Despite shallow depths, the initial response (in June 2000) of submerged plants was very limited and water remained highly turbid (due at first to abiotic seston and later to phytoplankton blooms). Turbidity decreased in July and the biomass of plants increased. However, submerged plant biomass did not exceed levels observed during summer 1999 (when water depths were greater) until August. Furthermore, a vascular plant-dominated assemblage (Vallisneria, Potamogeton, and Hydrilla) that occurred in 1999 was replaced with a community of nearly 98% Chara spp. (a macro-alga) in 2000. Hence, the lake"s submerged plant community appeared to revert to an earlier successional stage despite what appeared to be better conditions for growth. To explain this unexpected response, we evaluated the impacts that Hurricane Irene may have had on the lake in the previous

  15. Hurricane effects on a shallow lake ecosystem and its response to a controlled manipulation of water level.

    PubMed

    Havens, K E; Jin, K R; Rodusky, A J; Sharfstein, B; Brady, M A; East, T L; Iricanin, N; James, R T; Harwell, M C; Steinman, A D

    2001-04-01

    In order to reverse the damage to aquatic plant communities caused by multiple years of high water levels in Lake Okeechobee, Florida (U.S.), the Governing Board of the South Florida Water Management District (SFWMD) authorized a "managed recession" to substantially lower the surface elevation of the lake in spring 2000. The operation was intended to achieve lower water levels for at least 8 weeks during the summer growing season, and was predicted to result in a large-scale recovery of submerged vascular plants. We treated this operation as a whole ecosystem experiment, and assessed ecological responses using data from an existing network of water quality and submerged plant monitoring sites. As a result of large-scale discharges of water from the lake, coupled with losses to evaporation and to water supply deliveries to agriculture and other regional users, the lake surface elevation receded by approximately 1 m between April and June. Water depths in shoreline areas that historically supported submerged plant communities declined from near 1.5 m to below 0.5 m. Low water levels persisted for the entire summer. Despite shallow depths, the initial response (in June 2000) of submerged plants was very limited and water remained highly turbid (due at first to abiotic seston and later to phytoplankton blooms). Turbidity decreased in July and the biomass of plants increased. However, submerged plant biomass did not exceed levels observed during summer 1999 (when water depths were greater) until August. Furthermore, a vascular plant-dominated assemblage (Vallisneria, Potamogeton, and Hydrilla) that occurred in 1999 was replaced with a community of nearly 98% Chara spp. (a macro-alga) in 2000. Hence, the lake"s submerged plant community appeared to revert to an earlier successional stage despite what appeared to be better conditions for growth. To explain this unexpected response, we evaluated the impacts that Hurricane Irene may have had on the lake in the previous

  16. Water Wizards: School Program on Water Conservation for Third and Fourth Grade Levels.

    ERIC Educational Resources Information Center

    Massachusetts State Water Resources Authority, Boston.

    Water is precious. It is also easy to take for granted. Many people recognize that water is scarce in desert areas. but it is harder to realize that places like Massachusetts could face a shortage of pure drinking water. This manual provides teachers with curriculum resources to introduce concepts of water supply and water conservation to third…

  17. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability.

    PubMed

    Andersen, Martin S; Fuglei, Eva; König, Max; Lipasti, Inka; Pedersen, Åshild Ø; Polder, Anuschka; Yoccoz, Nigel G; Routti, Heli

    2015-04-01

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ13C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p'-DDE, mirex and PBDEs decreased 4-11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ13C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ13C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. PMID:25536177

  18. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability.

    PubMed

    Andersen, Martin S; Fuglei, Eva; König, Max; Lipasti, Inka; Pedersen, Åshild Ø; Polder, Anuschka; Yoccoz, Nigel G; Routti, Heli

    2015-04-01

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ13C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p'-DDE, mirex and PBDEs decreased 4-11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ13C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ13C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard.

  19. Assessment of persistent brominated and chlorinated organic contaminants in the European eel (Anguilla anguilla) in Flanders, Belgium: Levels, profiles and health risk.

    PubMed

    Malarvannan, Govindan; Belpaire, Claude; Geeraerts, Caroline; Eulaers, Igor; Neels, Hugo; Covaci, Adrian

    2014-06-01

    Pooled yellow European eel (Anguilla anguilla (L.)) samples, consisting of 3-10 eels, collected between 2000 and 2009 from 60 locations in Flanders (Belgium) were investigated for persistent contaminants, such as polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane and its metabolites (DDTs). The current study expands the knowledge regarding these contaminant concentrations, their patterns and distribution profiles in aquatic ecosystems. PBDEs, HBCDs, PCBs, and DDTs were detected in all eel samples and some samples had high concentrations (up to 1400, 9500, 41,600 and 7000ng/g lw, respectively). PCB levels accounted for the majority of the contamination in most samples. The high variability in PBDE, HBCD, PCB and DDT concentrations reported here is likely due to the variety in sampling locations demonstrating variable local pollution pressures, from highly industrialised areas to small rural creeks. Among PBDEs, BDE-47 (57% contribution to the sum PBDEs), -100 (19%) and -99 (15%) were the predominant congeners, similar to the composition reported in the literature in eel samples. For HBCDs, α-HBCD (74%) was predominant followed by γ-(22%) and β-HBCD (4%) isomers in almost all eel samples. CB-153 (19%) was the most dominant PCB congener, closely followed by CB-138 (11%), CB-180 (9%), CB-187 (8%) and CB-149 (7%). The contribution to the total human exposure through local wild eel consumption was also highly variable. Intake of PBDEs and HBCDs, through consumption of wild eel, was below the RfD values for the average population (consuming on average 2.9g eel/day). At 16 out 60 sites, eels exceeded largely the new EU consumption threshold for PCBs (300ng/g ww for the sum of 6 indicator PCBs). The current data shows an on-going exposure of Flemish eels to PBDEs, HBCDs, PCBs and DDTs through indirect release from contaminated sediments or direct releases from various industries.

  20. [Fluoride levels in commercial dentifrices and drinking water in Algeria].

    PubMed

    Merghache, D; Bellout, B; Merghache, S; Boucherit-Atmani, Z

    2011-12-01

    More and more scientific evidence show that fluorides have a cariostatic action to the plaque-saliva-tooth interface during cariogenous dissolution. Fluorides slow down demineralization and enhance remineralization. Their action is optimal, in the oral environment, when used at low concentrations on a continuous basis. The use of the fluorinated toothpastes during brushing of the teeth is a simple, rational method of daily topics application of fluorine, largely used in the context of prevention of dental caries and which can even be regarded as a public health measure. The water ingestion fluorinated represents itself an excellent average of the local application of fluorine. Our work concerned a quantitative study of fluorine in toothpaste and drinking water, and comparative between the local product and the imported one for the toothpastes, and the mineral water and public supply. The standard method of fluorine based on the potentiometry and distillation has shown that 50% of the tested toothpastes contain adequate concentration so that a product of dental care fights against decay. The Tlemcen tap water contains acceptable fluorine content, but the mineral water, with an excessive contribution, can cause fluorose. Of this, we can deduce that a topical application of a suitable quantity of fluorine on a daily basis in accordance with the precautions is not only the prevention of dental caries, but also to stabilize it if it already exists. PMID:22457989

  1. [Fluoride levels in commercial dentifrices and drinking water in Algeria].

    PubMed

    Merghache, D; Bellout, B; Merghache, S; Boucherit-Atmani, Z

    2011-12-01

    More and more scientific evidence show that fluorides have a cariostatic action to the plaque-saliva-tooth interface during cariogenous dissolution. Fluorides slow down demineralization and enhance remineralization. Their action is optimal, in the oral environment, when used at low concentrations on a continuous basis. The use of the fluorinated toothpastes during brushing of the teeth is a simple, rational method of daily topics application of fluorine, largely used in the context of prevention of dental caries and which can even be regarded as a public health measure. The water ingestion fluorinated represents itself an excellent average of the local application of fluorine. Our work concerned a quantitative study of fluorine in toothpaste and drinking water, and comparative between the local product and the imported one for the toothpastes, and the mineral water and public supply. The standard method of fluorine based on the potentiometry and distillation has shown that 50% of the tested toothpastes contain adequate concentration so that a product of dental care fights against decay. The Tlemcen tap water contains acceptable fluorine content, but the mineral water, with an excessive contribution, can cause fluorose. Of this, we can deduce that a topical application of a suitable quantity of fluorine on a daily basis in accordance with the precautions is not only the prevention of dental caries, but also to stabilize it if it already exists.

  2. Analysis of water levels in the Frenchman Flat area, Nevada Test Site

    SciTech Connect

    Bright, D.J.; Watkins, S.A.; Lisle, B.A.

    2001-04-18

    Analysis of water levels in 21 wells in the Frenchman Flat area, Nevada Test Site, provides information on the accuracy of hydraulic-head calculations, temporal water-level trends, and potential causes of water-level fluctuations. Accurate hydraulic heads are particularly important in Frenchman Flat where the hydraulic gradients are relatively flat (less than 1 foot per mile) in the alluvial aquifer. Temporal water-level trends with magnitudes near or exceeding the regional hydraulic gradient may have a substantial effect on ground-water flow directions. Water-level measurements can be adjusted for the effects of barometric pressure, formation water density (from water-temperature measurements), borehole deviation, and land-surface altitude in selected wells in the Frenchman Flat area. Water levels in one well were adjusted for the effect of density; this adjustment was significantly greater (about 17 feet) than the adjustment of water levels for barometric pressure, borehole deviation, or land-surface altitude (less than about 4 feet). Water-level measurements from five wells exhibited trends that were statistically and hydrologically significant. Statistically significant water-level trends were observed for three wells completed in the alluvial aquifer (WW-5a, UE-5n, and PW-3), for one well completed in the carbonate aquifer (SM-23), and for one well completed in the quartzite confining unit (Army-6a). Potential causes of water-level fluctuations in wells in the Frenchman Flat area include changes in atmospheric conditions (precipitation and barometric pressure), Earth tides, seismic activity, past underground nuclear testing, and nearby pumping. Periodic water-level measurements in some wells completed in the carbonate aquifer indicate cyclic-type water-level fluctuations that generally correlate with longer term changes (more than 5 years) in precipitation. Ground-water pumping from the alluvial aquifer at well WW-5c and pumping and discharge from well RNM- 2s

  3. Analysis of water levels in the Frenchman Flat area, Nevada Test Site

    USGS Publications Warehouse

    Bright, D.J.; Watkins, S.A.; Lisle, B.A.

    2001-01-01

    Analysis of water levels in 21 wells in the Frenchman Flat area, Nevada Test Site, provides information on the accuracy of hydraulic-head calculations, temporal water-level trends, and potential causes of water-level fluctuations. Accurate hydraulic heads are particularly important in Frenchman Flat where the hydraulic gradients are relatively flat (less than 1 foot per mile) in the alluvial aquifer. Temporal water-level trends with magnitudes near or exceeding the regional hydraulic gradient may have a substantial effect on ground-water flow directions. Water-level measurements can be adjusted for the effects of barometric pressure, formation water density (from water-temperature measurements), borehole deviation, and land-surface altitude in selected wells in the Frenchman Flat area. Water levels in one well were adjusted for the effect of density; this adjustment was significantly greater (about 17 feet) than the adjustment of water levels for barometric pressure, borehole deviation, or land-surface altitude (less than about 4 feet). Water-level measurements from five wells exhibited trends that were statistically and hydrologically significant. Statistically significant water-level trends were observed for three wells completed in the alluvial aquifer (WW-5a, UE-5n, and PW-3), for one well completed in the carbonate aquifer (SM-23), and for one well completed in the quartzite confining unit (Army-6a). Potential causes of water-level fluctuations in wells in the Frenchman Flat area include changes in atmospheric conditions (precipitation and barometric pressure), Earth tides, seismic activity, past underground nuclear testing, and nearby pumping. Periodic water-level measurements in some wells completed in the carbonate aquifer indicate cyclic-type water-level fluctuations that generally correlate with longer term changes (more than 5 years) in precipitation. Ground-water pumping fromthe alluvial aquifer at well WW-5c and pumping and discharge from well RNM-2s

  4. 26. JUNCTION STRUCTURE. WATER LEVEL 1190FT, INNER RING MIXER OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. JUNCTION STRUCTURE. WATER LEVEL 1190FT, INNER RING MIXER OF STATE AND COLORADO, WATER EXITS THROUGH OUTER RING. - F. E. Weymouth Filtration Plant, 700 North Moreno Avenue, La Verne, Los Angeles County, CA

  5. STATISTICAL PROCEDURES FOR DETERMINATION AND VERIFICATION OF MINIMUM REPORTING LEVELS FOR DRINKING WATER METHODS

    EPA Science Inventory

    The United States Environmental Protection Agency's (EPA) Office of Ground Water and Drinking Water (OGWDW) has developed a single-laboratory quantitation procedure: the lowest concentration minimum reporting level (LCMRL). The LCMRL is the lowest true concentration for which fu...

  6. Applying Water-Level Difference Control to Central Arizona Project

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Central Arizona Project (CAP) has been supplying Colorado River water to Central Arizona for roughly 25 years. The CAP canal is operated remotely with a Supervisory Control and Data Acquisition (SCADA) System. Gate position changes are made either manually or through the use of automatic control...

  7. Ground Water Level Measurements in Selected Boreholes Near the Site of the Proposed Repository

    SciTech Connect

    Page, H. Scott

    2007-11-29

    The Harry Reid Center for Environmental Studies (HRC) at the University of Nevada, Las Vegas (UNLV) acquired quarterly and continuous data on water levels from approximately 26 boreholes that comprise a periodic monitoring network (Table 1) between October 2003 and September 2007. During this period we continued to observe and analyze short and long-term ground water level trends in periodically monitored boreholes. In this report we summarize and discuss four key findings derived from analysis of water level data acquired during this period: 1. Rapid ground water level rise after storm events in Forty Mile Canyon; 2. Seismically-induced ground water level fluctuations; 3. A sample of synoptic observations and barometric influences on short term fluctuations; and 4. Long term ground water level trends observed from mid-2001 through late-2005.

  8. Analysis of water-level data in the Yucca Mountain area, Nevada, 1985--95

    SciTech Connect

    Graves, R.P.; Tucci, P.; O`Brien, G.M.

    1997-12-31

    From 1985 through 1995, a water-level network that consists of 28 wells for monitoring 36 depth intervals has been maintained in the Yucca Mountain area. The network includes wells that were measured manually, approximately monthly, and/or measured hourly with a transducer/data logger system. Manual water-level measurements were made with either calibrated steel tapes or single or multiconductor-cable units. All wells monitor water levels in Tertiary volcanic rocks, except one that monitors water levels in Paleozoic carbonate rocks. Annual mean water-level altitudes for all wells for the period 1985-95 ranged from 727.93 to 1,034.60 meters. The maximum range in water-level change between monthly measurements and/or monthly mean values was 12.22 meters in well USW H-3 lower interval, and the minimum range was 0.31 meter in wells UE-25 b-1 upper interval, and J-11. In 31 of the 36 depth intervals monitored, the range of water-level change was less than 1 meter. The range of standard deviation of all depth interval measurements for all wells that were monitored was 0.053 to 3.098 meters. No seasonal water-level trends were detected in any of the wells, and regional ground-water withdrawals did not appear to cause water-level changes. Most annual water-level fluctuations can be attributed to barometric and Earth-tide changes. Regional earthquakes, which occurred on June 28--29, 1992, might have simultaneously affected the water level in seven wells. Periods of rising and declining water levels were observed in most wells. However, 11 years of record were not sufficient to determine if these periods were cyclic. Because a goal of monitoring water levels at Yucca Mountain is to determine if there are water-level trends that could affect the potential repository, observed water-level changes over the period of this report may not be representative of the overall long-term trends in water levels.

  9. Summary of the Ground-Water-Level Hydrologic Conditions in New Jersey 2006

    USGS Publications Warehouse

    Jones, Walter; Pope, Daryll

    2007-01-01

    Ground water is one of the Nation's most important natural resources. It provides about 40 percent of our Nation's public water supply. Currently, nearly one-half of New Jersey's drinking-water is supplied by over 300,000 wells that serve more than 4.3 million people (John P. Nawyn, U.S. Geological Survey, written commun., 2007). New Jersey's population is projected to grow by more than a million people by 2030 (U.S. Census Bureau, accessed March 2, 2006, at http://www.census.gov). As demand for water increases, managing the development and use of the ground-water resource so that the supply can be maintained for an indefinite time without causing unacceptable environmental, economic, or social consequences is of paramount importance. This report describes the U.S. Geological Survey (USGS) New Jersey Water Science Center Observation Well Networks. Record low ground-water levels during water year 2006 (October 1, 2005 to September 30, 2006) are listed, and water levels in six selected water-table observation wells and three selected confined wells are shown in hydrographs. The report describes the trends in water levels in various confined aquifers in southern New Jersey and in water-table and fracture rock aquifers throughout the State. Web site addresses to access the data also are included. The USGS has operated a network of observation wells in New Jersey since 1923 for the purpose of monitoring ground-water-level changes throughout the State. Long-term systematic measurement of water levels in observation wells provides the data needed to evaluate changes in the ground-water resource over time. Records of ground-water levels are used to evaluate the effects of climate changes and water-supply development, to develop ground-water models, and to forecast trends.

  10. Ground-water levels in water years 1984-86 and estimated ground-water pumpage in water years 1984-85, Carson Valley, Douglas County, Nevada

    USGS Publications Warehouse

    Berger, D.L.

    1987-01-01

    Tabulations of groundwater level measurements made during the water years 1984-86 and summaries of estimated pumpage for water years 1984 and 1985 in Carson valley, Douglas County, Nevada, are included in this report. The data are being collected to provide a record of long-term groundwater changes and pumpage estimates that can be incorporated in a groundwater model change at a later date. (USGS)

  11. Persistence, transmission, and virulence characteristics of Aeromonas strains in a duckweed aquaculture-based hospital sewage water recycling plant in Bangladesh.

    PubMed

    Rahman, Mokhlasur; Huys, Geert; Rahman, Motiur; Albert, M John; Kühn, Inger; Möllby, Roland

    2007-03-01

    The persistence and transmission of Aeromonas in a duckweed aquaculture-based hospital sewage water treatment plant in Bangladesh was studied. A total of 670 samples from different sites of the hospital sewage water treatment plant, from feces of hospitalized children suffering from diarrhea, from environmental control ponds, and from feces of healthy humans were collected over a period of three years. In total, 1,315 presumptive Aeromonas isolates were biochemically typed by the PhenePlate rapid screening system (PhP-AE). A selection of 90 representative isolates was further analyzed with PhenePlate (PhP) extended typing (PhP-48), fatty acid methyl ester analysis, and amplified fragment length polymorphism (AFLP) fingerprinting. In addition, the prevalence of the putative virulence factors hemolysin and cytotoxin and the presence of the cytolytic enterotoxin gene (AHCYTOEN) were analyzed. Aeromonas was found at all sites of the treatment plant, in 40% of the samples from environmental control ponds, in 8.5% of the samples from hospitalized children suffering from diarrhea, and in 3.5% of samples from healthy humans. A significantly high number of Aeromonas bacteria was found in duckweed, which indicates that duckweed may serve as a reservoir for these bacteria. PhP-AE typing allowed identification of more than 192 distinct PhP types, of which 18 major PhP types (MTs) were found in multiple sites and during several occasions. AFLP fingerprinting revealed the prevalence of genotypically indistinguishable Aeromonas isolates among certain PhP MTs recovered from different sampling occasions and/or at multiple sites. Hemolytic and cytotoxic activities were observed in 43% of the tested strains, whereas 29% possessed the cytolytic enterotoxin gene AHCYTOEN. Collectively, two specific MTs associated with diarrhea were shown to exhibit high cytotoxicity. Furthermore, all tested isolates of these major types were positive for the cytolytic enterotoxin gene. In conclusion

  12. Water levels in major artesian aquifers of the New Jersey Coastal Plain, 1983

    USGS Publications Warehouse

    Eckel, J.A.; Walker, R.L.

    1986-01-01

    Water levels and changes in water levels in the major aquifers of the New Jersey Coastal Plain are documented. Water levels in 1,071 wells were measured in 1983, and are compared with 827 water level measurements made in the same wells in 1978. Increased groundwater withdrawals from the major artesian aquifers that underlie the New Jersey Coastal Plain have caused large cones of depression in the artesian heads. These cones are delineated on detailed potentiometric surface maps based on water level data collected in the fall of 1983. Hydrographs from observation wells show trends of water levels for the 6-year period of 1978 through 1983. The Potomac-Raritan-Magothy aquifer system is divided into the lower, middle, and upper aquifers. The potentiometric surfaces in these aquifers form large cones of depression centered in the Camden and Middlesex-Monmouth County areas. Measured water levels declined as much as 23 ft in these areas for the period of study. The lowest levels are 96 ft below sea level in Camden County and 91 ft below sea level in the Middlesex-Monmouth County area. Deep cones of depression in coastal Monmouth and Ocean counties in both the Englishtown aquifer system and Wenonah-Mount Laurel aquifer are similar in location and shape. This is because of an effective hydraulic connection between these aquifers. Measured water levels declined as much as 29 ft in the Englishtown aquifer system and 21 ft in the Wenonah-Mount Laurel aquifer during the period of study. The lowest levels are 249 ft below sea level in the Englishtown aquifer system and 196 ft below sea level in the Wenonah-Mount Laurel aquifer. Water levels in the Piney Point aquifer are as low as 75 ft below sea level at Seaside Park, Ocean County and 35 ft below sea level in southern Cumberland County. Water levels in Cumberland County are affected by large withdrawals of groundwater in Kent County, Delaware. Water levels in the Atlantic City 800 ft sand of the Kirkwood Formation define an

  13. Influence of summer water-level variability on St. Lawrence River-wetland fish assemblages

    USGS Publications Warehouse

    McKenna, J.E.; Barkley, J.L.; Johnson, J.H.

    2008-01-01

    Water-level and associated variability are substantial influences on wetland and shallow aquatic communities. The Akwesasne Wetland Complex is an extensive St. Lawrence River system affected by water regulation. The responses of fish assemblages to short-term summer water-level variation were examined throughout this section of the St. Lawrence River and its tributaries. An influence of water-level variability was detected on abundance of three common species [bluntnose minnow (Pimephales notatus), rock bass (Amboplites rupestris), and white sucker (Catastomus commersonii)] and explained 30-44% of variation. This influence has implications for water regulation and natural resource management, and a larger scope evaluation may reveal more extensive effects.

  14. Ground Water Levels for NGEE Areas A, B, C and D, Barrow, Alaska, 2012-2014

    DOE Data Explorer

    Anna Liljedahl; Cathy Wilson

    2015-06-08

    Ice wedge polygonal tundra water levels were measured at a total of 45 locations representing polygon centers and troughs during three summers. Early season water levels, which were still affected by ice and snow, are represented by manual measurements only. Continuous (less than hourly) measurements followed through early fall (around mid-Sep). The data set contains inundation depth (cm), absolute water level and local ground surface elevation (masl).

  15. Landscape-level variation in disease susceptibility related to shallow-water hypoxia.

    PubMed

    Breitburg, Denise L; Hondorp, Darryl; Audemard, Corinne; Carnegie, Ryan B; Burrell, Rebecca B; Trice, Mark; Clark, Virginia

    2015-01-01

    Diel-cycling hypoxia is widespread in shallow portions of estuaries and lagoons, especially in systems with high nutrient loads resulting from human activities. Far less is known about the effects of this form of hypoxia than deeper-water seasonal or persistent low dissolved oxygen. We examined field patterns of diel-cycling hypoxia and used field and laboratory experiments to test its effects on acquisition and progression of Perkinsus marinus infections in the eastern oyster, Crassostrea virginica, as well as on oyster growth and filtration. P. marinus infections cause the disease known as Dermo, have been responsible for declines in oyster populations, and have limited success of oyster restoration efforts. The severity of diel-cycling hypoxia varied among shallow monitored sites in Chesapeake Bay, and average daily minimum dissolved oxygen was positively correlated with average daily minimum pH. In both field and laboratory experiments, diel-cycling hypoxia increased acquisition and progression of infections, with stronger results found for younger (1-year-old) than older (2-3-year-old) oysters, and more pronounced effects on both infections and growth found in the field than in the laboratory. Filtration by oysters was reduced during brief periods of exposure to severe hypoxia. This should have reduced exposure to waterborne P. marinus, and contributed to the negative relationship found between hypoxia frequency and oyster growth. Negative effects of hypoxia on the host immune response is, therefore, the likely mechanism leading to elevated infections in oysters exposed to hypoxia relative to control treatments. Because there is considerable spatial variation in the frequency and severity of hypoxia, diel-cycling hypoxia may contribute to landscape-level spatial variation in disease dynamics within and among estuarine systems. PMID:25671595

  16. Evaluating changes to reservoir rule curves using historical water-level data

    USGS Publications Warehouse

    Mower, Ethan; Miranda, Leandro E.

    2013-01-01

    Flood control reservoirs are typically managed through rule curves (i.e. target water levels) which control the storage and release timing of flood waters. Changes to rule curves are often contemplated and requested by various user groups and management agencies with no information available about the actual flood risk of such requests. Methods of estimating flood risk in reservoirs are not easily available to those unfamiliar with hydrological models that track water movement through a river basin. We developed a quantile regression model that uses readily available daily water-level data to estimate risk of spilling. Our model provided a relatively simple process for estimating the maximum applicable water level under a specific flood risk for any day of the year. This water level represents an upper-limit umbrella under which water levels can be operated in a variety of ways. Our model allows the visualization of water-level management under a user-specified flood risk and provides a framework for incorporating the effect of a changing environment on water-level management in reservoirs, but is not designed to replace existing hydrological models. The model can improve communication and collaboration among agencies responsible for managing natural resources dependent on reservoir water levels.

  17. The effects of using ground water to maintain water levels of Cedar Lake, Wisconsin

    USGS Publications Warehouse

    McLeod, R.S.

    1980-01-01

    There were no identifiable changes in measured physical and chemical characteristics of lake water during sustained pumping of ground water into the lake, nor were there identifiable changes in the number or makeup of the phytoplankton community. Differences in physical and chemical characteristics of lake water and ground water added to the lake probably were not great enough to cause changes within the lake.

  18. ATRAZINE ECOLOGICAL EFFECTS ASSESSMENT FOR OPP LEVEL OF CONCERN AND OW WATER QUALITY CRITERION FOR AQUATIC LIFE

    EPA Science Inventory

    Atrazine is a relatively water-soluble and persistent herbicide that can reach concentrations of possible ecological concern for aquatic plants in vulnerable watersheds in regions with high agricultural usage of atrazine. As a consequence, the U.S. EPA Office of Water is current...

  19. Water level observations in mangrove swamps during two hurricanes in Florida

    USGS Publications Warehouse

    Krauss, K.W.; Doyle, T.W.; Doyle, T.J.; Swarzenski, C.M.; From, A.S.; Day, R.H.; Conner, W.H.

    2009-01-01

    Little is known about the effectiveness of mangroves in suppressing water level heights during landfall of tropical storms and hurricanes. Recent hurricane strikes along the Gulf Coast of the United States have impacted wetland integrity in some areas and hastened the need to understand how and to what degree coastal forested wetlands confer protection by reducing the height of peak water level. In recent years, U.S. Geological Survey Gulf Coast research projects in Florida have instrumented mangrove sites with continuous water level recorders. Our ad hoc network of water level recorders documented the rise, peak, and fall of water levels (?? 0.5 hr) from two hurricane events in 2004 and 2005. Reduction of peak water level heights from relatively in-line gages associated with one storm surge event indicated that mangrove wetlands can reduce water level height by as much as 9.4 cm/km inland over intact, relatively unchannelized expanses. During the other event, reductions were slightly less for mangroves along a river corridor. Estimates of water level attenuation were within the range reported in the literature but erred on the conservative side. These synoptic data from single storm events indicate that intact mangroves may support a protective role in reducing maximum water level height associated with surge. ?? 2009 The Society of Wetland Scientists.

  20. Persistent increase in alpha-fetoprotein level in a patient without underlying liver disease who underwent curative resection of hepatocellular carcinoma. A case report and review of the literature

    PubMed Central

    2012-01-01

    Introduction Alpha-fetoprotein (AFP) is an oncofetal protein produced by hepatocellular carcinoma (HCC). AFP level can also be elevated in other neoplastic or non-neoplastic conditions. An elevated AFP level has high diagnostic significance for HCC; at a level of >200 ng/mL, the probability of HCC is >90%. The aim of the present paper is to report a patient who underwent curative resection of HCC, who had a persistently elevated AFP level postoperatively but did not develop recurrence during a 2-year follow-up period. A review of the literature is also presented. Case report An 82-year-old male was referred following a computed tomography scan showing a 160 mm diameter mass in the left lobe of the liver. This huge mass was diagnosed as HCC, arising in the absence of cirrhosis or viral hepatitis. After tumor removal, the patient’s high AFP level persisted for 2 years. Conclusion As steatosis was the only pathological change in the remnant liver, this may have caused the persistently elevated AFP level in this patient. PMID:22559879

  1. Ground-water levels in Delaware in 1952

    USGS Publications Warehouse

    Marine, I.W.

    1954-01-01

    In 1943 the towns of Lewes and Rehoboth entered into cooperation with the U.S. Geological Survey in order to study salt-water encroachment in that area. Three observation wells were established, of which one, NI 3, had observations continued on the statewide program in 1952. Cooperation with the town was conducted in 1950. In December 1949 the State of Delaware, through the Agricultural Extension Service of the University of Delaware and the Highway Department, cooperated with the U.S. Geological Survey for the purpose of making of a reconnaissance study of ground water within the State. In the fall of 1950, under the cooperative agreement with the Agricultural Extension Service of the University of Delaware, 13 water-table wells were established for measurement. Beginning July 1, 1951, cooperation transferred to the Delaware Geological Survey of the University of Delaware, and measurement s continued the remainder of the year. Cooperation was also established with the Delaware Geological Survey representing the city of Newark for a detailed study of the Newark area. An additional observation well, Cb 123, was established in the course of this program.

  2. Ground-water levels in aquifers used for residential supply, Campton Township, Kane County, Illinois

    USGS Publications Warehouse

    Kay, Robert T.; Kraske, Kurt A.

    1996-01-01

    The U.S. Geological Survey, in cooperation with the Campton Township Board of Trustees, measured water levels in the aquifers used for residential supply in Campton Township, Kane County, Illinois. Aquifers used for residential supply are the shallow and deep aquifers in the glacial drift, composed of unconsolidated sand and gravels; the Alexandrian-Maquoketa aquifer, composed of dolomite and shale of the Alexandrian Series and the Maquoketa Group; the Galena-Platteville aquifer, composed of dolomite of the Platteville and Galena Groups; and the Ancell aquifer, composed of sandstones of the Glenwood Formation and the St. Peter Sanstone. Water-level altitudes in the shallow drift aquifers generally follow surface topography. Analysis of water-level data does not clearly indicate overutilization of these aquifers. Water-level altitudes in the deep drift aquifers decrease from west to east. Comparison of historical depth to water measurements with current (1995) measurements indicates large decreases in water levels in some areas. The deep drift aquifers may be overutilized at these locations. Water-level altitudes in the Alexandrian-Maquoketa aquifer generally decrease from west to east. The potentiometric surface of the aquifer follows the bedrock-surface topography in some locations. Localized low water-level altitudes and large decreases in water levels indicate the Alexandrian-Maquoketa aquifer is overutilized in several areas. Water-level altitudes in the wells finished in the Galena- Platteville aquifer vary by more than 300 feet. Large decreases in water levels in wells finished in the Galena-Platteville aquifer indicate the Galena-Platteville and Alexandrian-Maquoketa aquifers are overutilized in the northern part of the township. Water-level altitudes in the wells finished in the Ancell aquifer are also highly variable. There is no indication that the Ancell aquifer is overutilized.

  3. Water-level data for the industrial area northwest of Delaware City, Delaware, 1993-94

    USGS Publications Warehouse

    Donnelly, C.A.; Hinaman, K.C.

    1996-01-01

    Water-level data for 171 wells and one surface-water site on Red Lion Creek in the industrial area northwest of Delaware City, Delaware, are presented for 1993 and 1994. Eight sets of synoptic ground- water-level measurements collected between April 1993 and September 1994, and locations and field notes for the 171 wells are presented. A hydrograph from December 19, 1993 through November 8, 1994 is presented for one surface-water site on Red Lion Creek in the industrial area. Hydrographs from October 15, 1993 through November 8, 1994 are presented for eight wells screened in the water- table aquifer. The U.S. Army Corps of Engineers collected the synoptic ground-water-level measurements. The U.S. Geological Survey collected the continuously recorded water-level data.

  4. Ground-water-quality and ground-water-level data, Bernalillo County, central New Mexico, 1990-1993

    USGS Publications Warehouse

    Kues, G.E.; Garcia, B.M.

    1995-01-01

    Ground-water-quality and ground-water-level data were collected in four unincorporated areas of Bernalillo County during 1990-93. Twenty wells in the east mountain area of Bernalillo County were sampled approximately monthly between January 1990 and June 1993. The water samples were analyzed for concentrations of chloride and selected nutrient species; many of the samples also were analyzed for concentrations of total organic carbon and dissolved boron and iron. Eleven wells northeast of the city of Albuquerque, 20 wells in the Rio Grande Valley immediately north of Albuquerque, and 30 wells in the Rio Grande Valley immediately south of Albuquerque were sampled once each between December 1992 and September 1993; all water samples were analyzed for chloride and selected nutrient species, and selected samples from wells in the north and south valley areas were also analyzed for major dissolved constituents, iron, manganese, and methylene blue active substances. Samples from 10 of the wells in the north and south valley areas were analyzed for 47 selected pesticides. Field measurements of specific conductance, pH, temperature, and alkalinity were made on most samples at the time of sample collection. Water levels also were measured at the time of sample collection when possible. Results of the monthly water-quality and water-level monitoring in the east mountain area of Bernalillo County are presented in graphical form. Water-quality and water-level data collected from the other areas are presented in tabular form.

  5. Water mass change in the Amazon basin estimated by multi-temporal SAR data, GRACE gravimetry and water level observations

    NASA Astrophysics Data System (ADS)

    Spiridonova, S.; Seitz, F.; Hedman, K.; Meyer, F.

    2012-04-01

    The 2007 IPCC assessment report identified the land hydrology as one of the most uncertain components of the global water cycle. Variations of continental water masses occur in several compartments (e.g. surface and soil water, snow/ice, and groundwater). Mass variations and related changes of surface water exten-sions are being observed by contemporary space and in-situ observation systems such as GRACE gravim-etry, altimetry, optical/infrared sensors, SAR/InSAR, and in-situ river gauges. In this session we will present a regional multi-sensor study in the Amazon basin. The study focuses on the quantification of variations of water mass and water surface extent caused by extreme flood and drought situations that were frequent during the last decade. PALSAR data of two extreme events was selected; once when the Amazon River was flooded (March/April 2009) and once when the region suffered from a se-vere drought (October/November 2009). The advantage of using PALSAR is that it operates in L-Band and has the possibility to penetrate through the vegetation which is essential in the Amazon basin with its dense vegetation. Time series of water level variations were obtained from two in-situ gauges at Manacapuru and Obidos as well as from Envisat satellite altimetry. Total water storage change in the whole region was given by GRACE gravimetry. First, the variation of water mass is computed numerically using GRACE. Second the water level variations obtained from the two river gauges are analyzed with respect to observation of Envisat. Third the surface water extent is estimated by extracting water masks from PALSAR image data. The water mass change is obtained by intersecting the water masks with a medium resolution digital elevation model (SRTM). More specifically, water heights along the boundary of the river body were extracted from the DEM and processed for error reduction. Then, pixel heights within the river contour were interpolated with a Delaunay triangula

  6. 46 CFR 52.01-110 - Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CFR 52.01-1) except as noted otherwise in this section. (b) Water level indicators. (Modifies PG-60.1... 46 Shipping 2 2013-10-01 2013-10-01 false Water-level indicators, water columns, gauge-glass... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and...

  7. 46 CFR 52.01-110 - Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CFR 52.01-1) except as noted otherwise in this section. (b) Water level indicators. (Modifies PG-60.1... 46 Shipping 2 2011-10-01 2011-10-01 false Water-level indicators, water columns, gauge-glass... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and...

  8. 46 CFR 52.01-110 - Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CFR 52.01-1) except as noted otherwise in this section. (b) Water level indicators. (Modifies PG-60.1... 46 Shipping 2 2014-10-01 2014-10-01 false Water-level indicators, water columns, gauge-glass... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and...

  9. 46 CFR 52.01-110 - Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CFR 52.01-1) except as noted otherwise in this section. (b) Water level indicators. (Modifies PG-60.1... 46 Shipping 2 2010-10-01 2010-10-01 false Water-level indicators, water columns, gauge-glass... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and...

  10. 46 CFR 52.01-110 - Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CFR 52.01-1) except as noted otherwise in this section. (b) Water level indicators. (Modifies PG-60.1... 46 Shipping 2 2012-10-01 2012-10-01 false Water-level indicators, water columns, gauge-glass... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and...

  11. Water-Level Changes in the High Plains Aquifer, 1980 to 1995

    USGS Publications Warehouse

    McGuire, Virginia L.; Sharpe, Jennifer B.

    1997-01-01

    The High Plains aquifer underlies one of the major agricultural areas in the world, including parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Ground-water irrigation expanded rapidly after 1940 in the area underlain by the High Plains aquifer (called the 'High Plains region' in this report): 1949--2.1 million acres; 1959--6.1 million acres; 1969--9.0 million acres; 1978--12.9 million acres; and 1980--13.7 million acres (Gutentag and others, 1984; Thelin and Heimes, 1987). In 1990, 95 percent of the water withdrawn from the High Plains aquifer, 15.7 million acre-feet, was used for irrigation (Marilee Horn, U.S. Geological Survey, written commun., 1996). Water-level declines appeared in the High Plains aquifer soon after extensive ground-water irrigation development began. By 1980, water levels in the High Plains aquifer in parts of Texas, Oklahoma, and southwestern Kansas had declined more than 100 feet. In response to these declines, the U.S. Geological Survey, in cooperation with numerous Federal, State, and local water-resource agencies, began a ground-water monitoring program in 1988 to assess water-level change in the aquifer annually, using water-level measurements in more than 7,000 wells. The water-level measurements are made in winter or early spring, when water levels generally represent nonpumping conditions.

  12. Persistence of Fall 1988 Math 310, Math 12 & Math 13 Students through Transfer Level Math over Four Academic Years (Fall 1988-Spring 1992). Research Report #269.

    ERIC Educational Resources Information Center

    Kangas, Jon; Ma, Tony

    A study was conducted at Evergreen Valley College (EVC) and San Jose City College (SJCC) to determine persistence rates over 4 academic years for students with no previous college experience who entered arithmetic (Math 310), beginning algebra (Math 12), and intermediate algebra (Math 13) courses in fall 1988. The study sought to determine…

  13. Persistence of Fall 1988 ENGL 321 & ENGL 322 Students through Transfer Level English (1A) over Four Academic Years (Fall 1988-Spring 1992). Research Report #268.

    ERIC Educational Resources Information Center

    Kangas, Jon; Ma, Tony

    In fall 1992, a study was conducted at Evergreen Valley College (EVC) and San Jose City College (SJCC), in California, to measure the persistence rate over 4 academic years of students with no previous college experience who entered into a fundamentals of reading course (English 321) and an introduction to college reading course (English 322) in…

  14. Tide- and wind-driven variability of water level in Sansha Bay, Fujian, China

    NASA Astrophysics Data System (ADS)

    Lin, Hongyang; Hu, Jianyu; Zhu, Jia; Cheng, Peng; Chen, Zhaozhang; Sun, Zhenyu; Chen, Dewen

    2016-09-01

    This study analyzes water-level variability in Sansha Bay and its adjacent waters near Fujian, China, using water-level data observed from seven stations along the coast and wind data observed from a moored buoy near Mazu Island. At super- to near-inertial frequencies, tides dominated the water-level variations, mainly characterized by semi-diurnal (primarily M2, S2, and N2) and diurnal tides (primarily K1, O1). The correlation coefficients between residual (non-tidal) water-level time series and the observed wind-stress time series exceeded 0.78 at all stations, hinting that the wind acting on the study region was another factor modulating the water-level variability. A cross-wavelet and wavelet-coherence analysis further indicated that (i) the residual water level at each station was more coherent and out-of-phase with the alongshore winds mostly at sub-inertial time scales associated with synoptic weather changes; and (ii) the residual water-level difference between the outer and inner bay was more coherent with the cross-shore winds at discrete narrow frequency bands, with the wind leading by a certain phase. The analysis also implied that the monsoon relaxation period was more favorable for the formation of the land-sea breeze, modulating the residual water-level difference.

  15. Human Impacts on Tides Overwhelm the Effect of Sea Level Risee on Extreme Water Levels in the Rhine-Meuse Delta

    NASA Astrophysics Data System (ADS)

    Hoitink, T.; Vellinga, N.; Hoekstra, P.; Van Der Vegt, M.; Zhang, W.

    2014-12-01

    Mean sea level rise receives ample attention in the literature. However, peak water levels, which are most important for flood vulnerability and salinity intrusion in tidal river networks, may not be linearly related with mean surface levels. To quantify tidal and subtidal water level changes and to link these changes to human intervention, 70 years of water level data for the Rhine-Meuse tidal river network is analysed using a variety of statistical methods. Using a novel parameterization of probability density functions, mean high and low water levels are examined, and extreme water levels are investigated by applying the combined Mann-Kendall and Pettitt tests to find trends and trend changes. Tidal water levels are studied based on harmonic analysis. Results show that the mean water levels throughout the system rise with the same pace as the mean sea level. However, high and low water levels do not show the same increase, and the spatial variability in decadal trends in high- and low water levels is high. High water and low water extremes generally decrease. Both the extreme water level analysis and the harmonic analysis display significant trend breaks in 1970, 1981 and 1997. These breaks can be attributed to the closure of the Haringvliet estuary, the removal of sluices and the removal of a dam, respectively, which radically alter the tidal motion. These results demonstrate that the direct human influence on the tidal motion can overwhelm the effect of mean sea level rise on water level extremes.

  16. Do Amplitudes of Water Level Fluctuations Affect the Growth and Community Structure of Submerged Macrophytes?

    PubMed

    Wang, Mo-Zhu; Liu, Zheng-Yuan; Luo, Fang-Li; Lei, Guang-Chun; Li, Hong-Li

    2016-01-01

    Submerged macrophytes are subjected to potential mechanical stresses associated with fluctuating water levels in natural conditions. However, few experimental studies have been conducted to further understand the effects of water level fluctuating amplitude on submerged macrophyte species and their assemblages or communities. We designed a controlled experiment to investigate the responses of three submerged macrophyte species (Hydrilla verticillata, Ceratophyllum demersum and Elodea nuttallii) and their combinations in communities to three amplitudes (static, ± 30 cm, ± 60 cm) of water level fluctuations. Results showed that water level fluctuating amplitude had little effects on the community performance and the three tested species responded differently. H. verticillata exhibited more growth in static water and it was negatively affected by either of the water level fluctuations amplitude, however, growth parameters of H. verticillata in two fluctuating water level treatments (i.e., ± 30 cm, ± 60 cm) were not significantly different. On the other hand, the growth of C. demersum was not significantly correlated with different amplitude treatments. However, it became more abundant when water levels fluctuated. E. nuttallii was inhibited by the two fluctuating water level treatments, and was less in growth parameters compared to the other species especially in water level fluctuating conditions. The inherent differences in the adaptive capabilities of the tested species indicate that C. demersum or other species with similar responses may be dominant species to restore submerged macrophyte communities with great fluctuating water levels. Otherwise, H. verticillata, E. nuttallii or other species with similar responses could be considered for constructing the community in static water conditions.

  17. Do Amplitudes of Water Level Fluctuations Affect the Growth and Community Structure of Submerged Macrophytes?

    PubMed Central

    Wang, Mo-Zhu; Liu, Zheng-Yuan; Luo, Fang-Li; Lei, Guang-Chun; Li, Hong-Li

    2016-01-01

    Submerged macrophytes are subjected to potential mechanical stresses associated with fluctuating water levels in natural conditions. However, few experimental studies have been conducted to further understand the effects of water level fluctuating amplitude on submerged macrophyte species and their assemblages or communities. We designed a controlled experiment to investigate the responses of three submerged macrophyte species (Hydrilla verticillata, Ceratophyllum demersum and Elodea nuttallii) and their combinations in communities to three amplitudes (static, ± 30 cm, ± 60 cm) of water level fluctuations. Results showed that water level fluctuating amplitude had little effects on the community performance and the three tested species responded differently. H. verticillata exhibited more growth in static water and it was negatively affected by either of the water level fluctuations amplitude, however, growth parameters of H. verticillata in two fluctuating water level treatments (i.e., ± 30 cm, ± 60 cm) were not significantly different. On the other hand, the growth of C. demersum was not significantly correlated with different amplitude treatments. However, it became more abundant when water levels fluctuated. E. nuttallii was inhibited by the two fluctuating water level treatments, and was less in growth parameters compared to the other species especially in water level fluctuating conditions. The inherent differences in the adaptive capabilities of the tested species indicate that C. demersum or other species with similar responses may be dominant species to restore submerged macrophyte communities with great fluctuating water levels. Otherwise, H. verticillata, E. nuttallii or other species with similar responses could be considered for constructing the community in static water conditions. PMID:26735689

  18. HLA-DRB1 Class II antigen level alleles are associated with persistent HPV infection in Mexican women; a pilot study

    PubMed Central

    2013-01-01

    Background Persistent infection with high-risk human papillomavirus (HPV) is a major risk factor for malignant lesions and cervical cancer. A widely studied element in the search for genetic factors influencing risk HPV infection diseases is allelic variation of the human leukocyte antigen (HLA) locus. The study was designed to search for HLA susceptibility alleles contributing to the persistence of HPV infection in Mexican women. Methods A total of 172 subjects were divided into three groups: 1) HPV–persistent patients; 2) HPV–cleared; and 3) HPV–reinfected patients. They were screened for HPV types using a polymerase chain reaction (PCR). PCR-sequence specific oligonucleotide probes (PCR-SSOP) was used for HLA DRB1 and DQB1 typing. Results We observed that HLA-DQB1*0501 allele might be associated with susceptibility of reinfection with HPV (p = 0.01, OR = 4.9, CI 95% = 1.3 -18.7). Allele frequency of HLA-DRB1*14 was particularly reduced in patients with cancer when compared with the HPV–persistent group (p = 0.04), suggesting that this allele is a possible protective factor for the development of cervical cancer (OR = 2.98). HLA-DRB1*07 might be associated with viral clearance (p = 0.04). Conclusions Genetic markers for HPV infection susceptibility are different in each population, in Mexicans several HLA-DQB1 alleles might be associated with an enhanced risk for viral persistence. In contrast, DRB1*14, seems to confer protection against cervical cancer. PMID:24000898

  19. Small Differences in Water Level Impacted Straighthead Ratings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Straighthead (STHD) is a physiological disorder that results in sterile rice panicles that remain upright at maturity. Depending on the rice variety and its level of host plant resistance, yields can be reduced significantly. The underlying cause of STHD is unknown, but it has been linked to nitroge...

  20. Bridge over Troubled Waters: Training for Department Level Supervisors.

    ERIC Educational Resources Information Center

    Cook, Gillian E.; Skipper, Barbara L.

    A clinical supervision training program has provided department level coordinators with support in their role as a bridge between administrators and teachers in six high schools and nine middle schools in a San Antonio, Texas, school district. This paper identifies major characteristics of the training program's model, describes the program, and…

  1. Metabolic aspects of bacterial persisters

    PubMed Central

    Prax, Marcel; Bertram, Ralph

    2014-01-01

    Persister cells form a multi-drug tolerant subpopulation within an isogenic culture of bacteria that are genetically susceptible to antibiotics. Studies with different Gram negative and Gram positive bacteria have identified a large number of genes associated with the persister state. In contrast, the revelation of persister metabolism has only been addressed recently. We here summarize metabolic aspects of persisters, which includes an overview about the bifunctional role of selected carbohydrates as both triggers for the exit from the drug tolerant state and metabolites which persisters feed on. Also alarmones as indicators for starvation have been shown to influence persister levels via different signaling cascades involving the activation of toxin-antitoxin systems and other regulatory factors. Finally, recent data obtained by 13C-isotopolog profiling demonstrated an active amino acid anabolism in Staphylococcus aureus cultures challenged with high drug concentrations. Understanding the metabolism of persister cells poses challenges but also paves the way for the development of anti-persister compounds. PMID:25374846

  2. Ground-water pumpage and water-level changes in the Milwaukee-Waukesha area, Wisconsin, 1950-61

    USGS Publications Warehouse

    Green, J.H.; Hutchinson, R.D.

    1965-01-01

    Artesian water pressure in the deep sandstone aquifer continued to decline throughout most of the Milwaukee-Waukesha area, Wisconsin between 1950 and 1961. Areas of greatest water-level decline were in northeast Waukesha County and in northwest Milwaukee County. The chief cause of the decline was continued heavy pumpage. The major aquifers of southeastern Wisconsin are the Niagara aquifer, which is primarily Niagara Dolomite of Silurian age, and the sandstone aquifer, which consists of sandstones of Cambrian and Ordovician ages. Locally, the glacial sands and gravels ,of Pleistocene age also are important aquifers. In the Milwaukee-Waukesha area, the sandstone aquifer is completely artesian, confined above by the Maquoketa Shale. The Niagara aquifer is generally unconfined. Pumpage from the sandstone aquifer in the Milwaukee-Waukesha area de- creased from about 23.3 million gallons per day in 1950 to about 20.9 million gallons per day in 1961. The principal reason for decreased pumpage was sub- stitution of surface-water supply from Lake Michigan. Between 1950 and 1961, the water-level changes in wells in the sandstone aquifer ranged from plus 10 feet at Town of Lake to minus 98 feet in northwest Milwaukee. Except for a small area near Town of Lake, water levels in wells in the Milwaukee-Waukesha area were lower in 1961 than in 1950. Water-level changes were directly related to the pumpage pattern and pump- age changes. Increased pumpage at Waukesha and in northwest Milwaukee and continued heavy pumpage at Wauwatosa caused widespread water-level declines in northeast Waukesha County and in northwest Milwaukee County. Locally, decreased pumpage at West Milwaukee allowed limited recovery of water levels since 1957. Estimates of pumpage through the year 1975 indicate a pumpage decrease in the middle 1960's, followed by an increase in the late 1960's and early 1970's. Additional conversion to surface-water supply in Milwaukee County will account for most pumpage

  3. Young Valley Networks on Mars: Persistent Flow of Water in Lyot Crater, a Distinctive Amazonian Impact Basin Microenvironment

    NASA Astrophysics Data System (ADS)

    Dickson, J.; Fassett, C.; Head, J.

    2008-09-01

    Introduction While Amazonian fluvial landforms are not abundant on Mars, remote sensing data have revealed details regarding the role of ice in non-polar regions in the Amazonian. Evidence includes 1) deposits interpreted to be remnants of cold-based glaciers at low- and mid-latitudes [1-6]; 2) mantling deposits interpreted to be a desiccating layer of ground ice [7- 8]; 3) detection of hydrogen (inferred to be bound as water ice) in soil in the mid- and high-latitudes in each hemisphere [9-10]; and 4) viscous flow features interpreted to be the product of glacial-like flow along steep valley/crater walls [11-12]. The climate of Mars straddles the triple point, which motivated us to investigate the most-likely locations/microclimates for melting of these surface/near-surface ice features [13-14]: large-scale impact craters at low elevations and mid-latitudes, which provide 1) relatively high surface pressure; 2) increased solor insolation; and 3) potential residual thermal anomalies from the impact event. Lyot Crater, a ~215 km peak-ring impact basin in the northern lowlands of Mars (50°N, 30°E), provides an environment that meets these constraints. We analyzed recently obtained CTX data to document evidence of remnant glacial deposits and surface features that appear indicative of melting and drainage. Description The floor of Lyot exhibits several networks of sinuous valleys that have been incised exclusively into a pervasive stippled mantling unit (Fig. 1). Twenty separate networks are observed in CTX and THEMIS data, 15 of which occur in the eastern half of Lyot. The valleys range in length from short, 2 km long isolated valleys to 50 km long networks of multiple valleys that have widths that average ~250 m. Valley floors are smooth at CTX resolution, in contrast to the adjacent stippled mantling unit (Fig. 1). Profiles extracted from the Mars Orbiter Laser Altimeter (MOLA) data set show that, without exception, the valleys follow the local topographic

  4. Towards risk-based drought management in the Netherlands: making water supply levels transparent to water users

    NASA Astrophysics Data System (ADS)

    Maat Judith, Ter; Marjolein, Mens; Vuren Saskia, Van; der Vat Marnix, Van

    2016-04-01

    To prepare the Dutch Delta for future droughts and water scarcity, a nation-wide 4-year project, called Delta Programme, assessed the impact of climate change and socio-economic development, and explored strategies to deal with these impacts. The Programme initiated a joint approach to water supply management with stakeholders and developed a national adaptation plan that is able to adapt to future uncertain conditions. The adaptation plan consists of a set of preferred policy pathways - sequences of possible actions and measures through time - to achieve targets while responding in a flexible manner to uncertain developments over time, allowing room to respond to new opportunities and insights. With regard to fresh water allocation, the Delta Programme stated that supplying water of sufficient quality is a shared responsibility that requires cohesive efforts among users in the main and regional water system. The national and local authorities and water users involved agreed that the water availability and, where relevant, the water quality should be as transparent and predictable as possible under normal, dry and extremely dry conditions. They therefore introduced the concept of "water supply service levels", which should describe water availability and quality that can be delivered with a certain return period, for all regions and all relevant water users in the Netherlands. The service levels form an addition to the present policy and should be decided on by 2021. At present water allocation during periods of (expected) water shortage occurs according to a prearranged ranking system (a water hierarchy scheme based on a list of priorities), if water availability drops below a critical low level. The aim is to have supply levels available that are based on the probability of occurrence and economic impact of water shortage, and that are transparent for all water users in the regional water systems and the main water system. As part of the European project

  5. Estimation of missing water-level data for the Everglades Depth Estimation Network (EDEN), 2013 update

    USGS Publications Warehouse

    Petkewich, Matthew D.; Conrads, Paul A.

    2013-01-01

    The Everglades Depth Estimation Network is an integrated network of real-time water-level gaging stations, a ground-elevation model, and a water-surface elevation model designed to provide scientists, engineers, and water-resource managers with water-level and water-depth information (1991-2013) for the entire freshwater portion of the Greater Everglades. The U.S. Geological Survey Greater Everglades Priority Ecosystems Science provides support for the Everglades Depth Estimation Network in order for the Network to provide quality-assured monitoring data for the U.S. Army Corps of Engineers Comprehensive Everglades Restoration Plan. In a previous study, water-level estimation equations were developed to fill in missing data to increase the accuracy of the daily water-surface elevation model. During this study, those equations were updated because of the addition and removal of water-level gaging stations, the consistent use of water-level data relative to the North American Vertical Datum of 1988, and availability of recent data (March 1, 2006, to September 30, 2011). Up to three linear regression equations were developed for each station by using three different input stations to minimize the occurrences of missing data for an input station. Of the 667 water-level estimation equations developed to fill missing data at 223 stations, more than 72 percent of the equations have coefficients of determination greater than 0.90, and 97 percent have coefficients of determination greater than 0.70.

  6. Fuzzy logic control of water level in advanced boiling water reactor

    SciTech Connect

    Lin, Chaung; Lee, Chi-Szu; Raghavan, R.; Fahrner, D.M.

    1995-12-31

    The feedwater control system in the Advanced Boiling Water Reactor (ABWR) is more challenging to design compared to other control systems in the plant, due to the possible change in level from void collapses and swells during transient events. A basic fuzzy logic controller is developed using a simplified ABWR mathematical model to demonstrate and compare the performance of this controller with a simplified conventional controller. To reduce the design effort, methods are developed to automatically tune the scaling factors and control rules. As a first step in developing the fuzzy controller, a fuzzy controller with a limited number of rules is developed to respond to normal plant transients such as setpoint changes of plant parameters and load demand changes. Various simulations for setpoint and load demand changes of plant performances were conducted to evaluate the modeled fuzzy logic design against the simplified ABWR model control system. The simulation results show that the performance of the fuzzy logic controller is comparable to that of the Proportional-Integral (PI) controller, However, the fuzzy logic controller produced shorter settling time for step setpoint changes compared to the simplified conventional controller.

  7. What happens to near-shore habitat when lake and reservoir water levels decline?

    EPA Science Inventory

    Water management and drought can lead to increased fluctuation and declines in lake and reservoir water levels. These changes can affect near-shore physical habitat and the biotic assemblages that depend upon it. Structural complexity at the land-water interface of lakes promote...

  8. Hydrologic and climatologic factors affecting water levels of Devils Lake, North Dakota

    USGS Publications Warehouse

    Wiche, G.J.

    1986-01-01

    High water levels of Devils Lake, North Dakota, and other terminal lakes, have, in recent years, threatened highways, agricultural land, recreational cabins, and communities located near these lakes. This study was undertaken to describe the hydrology of the Devils Lake basin and to determine how to estimate future water level probabilities. Analysis of the available hydrologic and climatologic data indicates the water level of Devils Lake fluctuates largely in response to climatic variability. Average annual net storage gain has varied from 70 ,000 acre-feet for 1969-83 to as little as 4,530 acre-feet for 1931-40. In addition to the influence of climatic variability on the inflow to Devils Lake, an interconnected chain of lakes upstream of Devils Lake retains runoff and acts as an evaporation basin for runoff from the Devils Lake basin. During 1965-67, at least 112,000 acre-feet of water was stored in this upstream chain of lakes. A review of research conducted on other terminal lakes indicated that the water level in these lakes fluctuated primarily in response to climate variability. There is agreement between water level fluctuations of terminal lakes in Western North America and water level fluctuations of Devils lake during times of climatic extremes. No standardized methods are available for computing water level probabilities of terminal lakes. Most of the development of a method for determining future water level probabilities has been focused on Great Salt Lake, Utah. A number of techniques have been used to estimate the future water-level probabilities for Great Salt Lake; however, they provide a wide range in probability of occurrence for any given water level. (Author 's abstract)

  9. Water-Level Changes in Aquifers of the Atlantic Coastal Plain, Predevelopment to 2000

    USGS Publications Warehouse

    dePaul, Vincent T.; Rice, Donald E.; Zapecza, Otto S.

    2008-01-01

    The Atlantic Coastal Plain aquifer system, which underlies a large part of the east coast of the United States, is an important source of water for more than 20 million people. As the population of the region increases, further demand is being placed on those ground-water resources. To define areas of past and current declines in ground-water levels, as well as to document changes in those levels, historical water-level data from more than 4,000 wells completed in 13 regional aquifers in the Atlantic Coastal Plain were examined. From predevelopment to 1980, substantial water-level declines occurred in many areas of the Atlantic Coastal Plain. Regional variability in water-level change in the confined aquifers of the Atlantic Coastal Plain resulted from regional differences in aquifer properties and patterns of ground-water withdrawals. Within the Northern Atlantic Coastal Plain, declines of more than 100 ft were observed in New Jersey, Delaware, Maryland, Virginia, and North Carolina. Regional declines in water levels were most widespread in the deeper aquifers that were most effectively confined?the Upper, Middle, and Lower Potomac aquifers. Within these aquifers, water levels had declined up to 200 ft in southern Virginia and to more than 100 ft in New Jersey, Delaware, Maryland, and North Carolina. Substantial water-level declines were also evident in the regional Lower Chesapeake aquifer in southeastern New Jersey; in the Castle Hayne-Piney Point aquifer in Delaware, Maryland, southern Virginia and east-central North Carolina; in the Peedee-Severn aquifer in east-central New Jersey and southeastern North Carolina; and in the Black Creek-Matawan aquifer in east-central New Jersey and east-central North Carolina. Conversely, declines were least severe in the regional Upper Chesapeake aquifer during this period. In the Southeastern Coastal Plain, declines of more than 100 ft in the Chattahoochee River aquifer occurred in eastern South Carolina and in southwestern

  10. The status of streamflow and ground-water-level monitoring networks in Maryland, 2005

    USGS Publications Warehouse

    Gerhart, James M.; Cleaves, Emery T.

    2005-01-01

    The monitoring of streamflow and ground-water levels in Maryland is vitally important to the effective management and protection of the State?s water resources. Streamflow and ground-water-level monitoring networks have been operated for many years in Maryland, and in recent years, these networks have been redesigned to improve their efficiency. Unfortunately, these networks are increasingly at risk due to reduced and fluctuating funding from Federal, State, and local agencies. Stable, long-term funding is necessary to ensure that these networks will continue to provide valuable water data for use by State and local water-resources managers.

  11. Water-level maps of the alluvial aquifer, northwestern Mississippi, September 1981

    USGS Publications Warehouse

    Darden, Daphne

    1982-01-01

    Water levels were measured in 427 wells in the Mississippi River valley alluvial aquifer in northwestern Mississippi during the period September 15-28, 1981. Water levels in the alluvial sands and gravel were generally lower than water levels in September 1980 and larger depressions in the surface of the ground-water body were detected in the Sunflower-Leflore County area and in Humphreys County. These depressions are attributed to heavy pumping for irrigation and to less-than normal rainfall. Other smaller depressions are attributed to local heavy pumping. (USGS)

  12. Water-level records for the Big Sioux Aquifer, Minnehaha County, South Dakota

    USGS Publications Warehouse

    Bradford, Wendell L.

    1981-01-01

    This report contains a tabulation of water levels in wells tapping the Big Sioux aquifer in Minnehaha County, S. Dak. Included is a compilation of all water levels in 43 wells measured by the U.S. Geological Survey and State agencies during the period 1957-80. The data are presented in tabular and graphic form. (USGS)

  13. Water-level records for the northern High Plains of Colorado, 1979-83

    USGS Publications Warehouse

    Blattner, Joe L.; Rasmuson, Bruce D.

    1983-01-01

    Water-level measurements were made in 638 wells in the winter of 1982-83, in the northern High Plains of Colorado. The water-level measurements for the winter of 1982-83 and for four preceding winters are given in a table, which also contains the location, depth, land-surface elevation and the aquifer for each well. (USGS)

  14. Numeric removal action levels for contaminated drinking water sites. Update 2. Directive

    SciTech Connect

    1995-03-01

    This document is an updated table of numeric action levels for contaminated drinking water sites. It was originally published as an attachment to 9360.1-02 (Oct. 93) which described the new methodology used by OERR to calculate removal action levels (RALs) in drinking water.

  15. Water levels in continuously monitored wells in the Yucca Mountain Area, Nevada, 1989

    SciTech Connect

    Lobmeyer, D.H.; Luckey, R.R.; O`Brien, G.M.; Burkhardt, D.J.

    1995-02-01

    Water levels have been monitored hourly in 16 wells representing 24 intervals in the Yucca Mountain area, Nevada. Water levels were monitored using pressure transducers and were recorded by data loggers. The pressure transducers were periodically calibrated by raising and lowering them in the wells. The water levels were normally measured at approximately the same time that the transducers were calibrated. Where the transducer output appeared reasonable, it was converted to water levels using the calibrations and manual water-level measurements. The amount of transducer output that was converted to water levels ranged from zero for one interval to 100 percent for one interval. Fifteen of the wells were completed in Tertiary volcanic rocks and one well was completed in Paleozoic carbonate rocks. Each well monitored from one to four depth intervals. Water-level fluctuation caused by barometric pressure changes and earth tides were observed. Transducer output is presented in graphic form and, where appropriate, water-level altitude is presented in graphical and tabular form.

  16. Simulation of the effects of rainfall and groundwater use on historical lake water levels, groundwater levels, and spring flows in central Florida

    USGS Publications Warehouse

    O'Reilly, Andrew M.; Roehl, Edwin A.; Conrads, Paul A.; Daamen, Ruby C.; Petkewich, Matthew D.

    2014-01-01

    in water levels and flows were identified that are consistent with historical groundwater-use patterns. The sensitivity of the hydrologic system to rainfall is expected, owing to the well-drained karst terrain and relatively thin confinement of the Floridan aquifer system in much of central Florida. These characteristics facilitate the relatively rapid transmission of infiltrating water from rainfall to the water table and contribute to downward leakage of water to the Floridan aquifer system. The areally distributed nature of rainfall, as opposed to the site-specific nature of groundwater use, and the generally high transmissivity and low storativity properties of the semiconfined Floridan aquifer system contribute to the prevalence of water-level and flow patterns that mimic rainfall patterns. In general, the data-mining analyses demonstrate that the hydrologic system in central Florida is affected by groundwater use differently during wet periods, when little or no system storage is available (high water levels), compared to dry periods, when there is excess system storage (low water levels). Thus, by driving the overall behavior of the system, rainfall indirectly influences the degree to which groundwater use will effect persistent trends in water levels and flows, with groundwater-use impacts more prevalent during periods of low water levels and spring flows caused by low rainfall and less prevalent during periods of high water levels and spring flows caused by high rainfall. Differences in the magnitudes of rainfall and groundwater use during wet and dry periods also are important determinants of hydrologic response. An important implication of the data-mining analyses is that rainfall variability at subannual to multidecadal timescales must be considered in combination with groundwater use to provide robust system-response predictions that enhance sustainable resource management in an open karst aquifer system. The data-driven approach was limited, however, by

  17. Pancreatic cancer mortality and total hardness levels in Taiwan's drinking water.

    PubMed

    Yang, C Y; Chiu, H F; Cheng, M F; Tsai, S S; Hung, C F; Tseng, Y T

    1999-03-12

    The possible association between the risk of pancreatic cancer mortality and hardness levels in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. All eligible pancreatic cancer deaths (883 cases) of Taiwan residents from 1990 through 1994 were compared with deaths from other causes (883 controls), and the hardness levels of the drinking water used by these residents were determined. Data on water hardness throughout Taiwan was collected from Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes and were pair matched to the cancer cases by sex, year of birth, and year of death. The results show that there is a 39 % excess risk of mortality from pancreatic cancer in relation to the use of soft water. Trend analyses showed an increasing odds ratio for pancreatic cancer with decreasing levels of hardness in drinking water. This is an important finding for the Taiwan water industry and human health.

  18. Projections of extreme water level events for atolls in the western Tropical Pacific

    NASA Astrophysics Data System (ADS)

    Merrifield, M. A.; Becker, J. M.; Ford, M.; Yao, Y.

    2014-12-01

    Conditions that lead to extreme water levels and coastal flooding are examined for atolls in the Republic of the Marshall Islands based on a recent field study of wave transformations over fringing reefs, tide gauge observations, and wave model hindcasts. Wave-driven water level extremes pose the largest threat to atoll shorelines, with coastal levels scaling as approximately one-third of the incident breaking wave height. The wave-driven coastal water level is partitioned into a mean setup, low frequency oscillations associated with cross-reef quasi-standing modes, and wind waves that reach the shore after undergoing high dissipation due to breaking and bottom friction. All three components depend on the water level over the reef; however, the sum of the components is independent of water level due to cancelling effects. Wave hindcasts suggest that wave-driven water level extremes capable of coastal flooding are infrequent events that require a peak wave event to coincide with mid- to high-tide conditions. Interannual and decadal variations in sea level do not change the frequency of these events appreciably. Future sea-level rise scenarios significantly increase the flooding threat associated with wave events, with a nearly exponential increase in flooding days per year as sea level exceeds 0.3 to 1.0 m above current levels.

  19. Water-level altitudes 1998 and water-level changes 1990-98 and 1997-98 in the Chicot and Evangeline aquifers, Fort Bend County and adjacent areas, Texas

    USGS Publications Warehouse

    Coplin, L.S.; Santos, H.X.

    1998-01-01

    This report is one in an annual series of reports that depicts water-level altitudes and water-level changes since 1990 in the Chicot and Evangeline aquifers in Fort Bend County and adjacent areas, Texas. The report, prepared in cooperation with the Ford Bend Subsidence District, presents maps for the Chicot and Evangeline aquifers showing the approximate water-level altitudes in wells in 1998 and approximate water-level changes in wells from 1990 to 1998 and from 1997 to 1998. The most recent previously published water-level-altitude maps and water-level-change maps for the two aquifers are by Coplin and others (1997). The earliest water-level-altitude maps and water-level-change maps for the Chicot aquifer are by Wesselman (1972). The first maps of water-level altitudes and water-level changes for the Chicot and Evangeline aquifers are by Locke (1990).

  20. Spring water level stabilization and relationships between hydrologic, biologic, and fishery characteristics of TVA reservoirs

    SciTech Connect

    Yeager, B.L.; McDonough, T.A.; Taylor, J.

    1992-01-01

    Reservoir operations and annual variation in hydrology result in substantial fluctuations of water level within impoundments. Since the 1950s, TVA has attempted to stabilize tributary reservoir pool levels for a two-week period when water temperatures reach 65[degree]F at a depth of five feet. These conditions approximate the peak spawning season for largemouth bass, an important sport fish of the Tennessee River Valley. The current water level stabilization program was established to benefit largemouth bass. However, the benefits of the current spring stabilization procedures accrue, not to bass, but to another important sportfish, the white crappie. An earlier stabilization period would likely be of even greater benefit to white crappie. Phase-two of this project will provide a more detailed evaluation of the effects of timing and duration of spring water level stabilization and allow us to recommend specific optimizing modifications. Pending these recommendations, the water level stabilization program should continue as implemented.

  1. An Analysis of Historical Impacts of Water Resources Development on Water Levels of the Mekong River (Invited)

    NASA Astrophysics Data System (ADS)

    Cochrane, T. A.; Arias, M. E.; Piman, T.

    2013-12-01

    The rapid rate of water resources development in the Mekong basin of Southeast Asia is a cause for concern due to potential impacts on highly valued fisheries and natural ecosystems. Historical water levels of the Mekong were analyzed by comparing pre and post 1991 daily data of 6 stations along the mainstream from Chiang Sean, in northern Lao PDR and Thailand, to Stung Treng, in Cambodia, and the Pre Kdam station near the Tonle Sap Lake in the lower Mekong floodplain using the Indicators of Hydrological Alteration (IHA) software. The year 1991 marks a turning point in the rate of development in the basin, with the start of development of mainstream dams in the upper Mekong and accelerated hydropower and irrigation development in key tributaries. Observed changes in water level patterns along the Mekong were linked to temporal and spatial water resources development from 1960 to 2010. Variations in climate were accounted for and are important, but they were not observed to be the main causes of changes in key hydrological indicators related to ecosystem productivity. The development of mainstream dams in the upper Mekong basin in the post 1991 period resulted in a significant change of seasonal water levels, raise rates, fall rates, and the number of water level fluctuations at Chiang Sean. This effect diminishes downstream until it becomes negligible at the Mukdahan monitoring station in Thailand, which represents a drainage area of over 50% of the total Mekong Basin. Further downstream at Pakse station in Southern Lao PDR, changes in hydrological indicators post 1991 were observed to be significant again, which can be directly attributed to water resource development in the Chi and Mun River basins in Northeastern Thailand. A reduction of 23% and 11% in water level raising rates and fall rates, respectively at Prek Kdam, provides clear evidence of a diminished flood pulse of the Tonle Sap Lake in the post 1991 period. Given the observed water level alterations

  2. Effects of Water Level on Three Wetlands Soil Seed Banks on the Tibetan Plateau

    PubMed Central

    Ma, Miaojun; Ma, Zhen; Du, Guozhen

    2014-01-01

    Background Although the effect of water level on germination in soil seed banks has been documented in many ecosystems, the mechanism is not fully understood, and to date no empirical studies on this subject exist. Further, no work has been done on the effect of water level on seed banks of drying and saline-alkaline wetlands in alpine areas on the Tibetan Plateau. Methodology We examined the effects of water level (0 cm, 5 cm and 10 cm) on seed germination and seedling establishment from soil seed banks at 0–5 cm and 5–10 cm depths in typical, drying, and saline-alkaline wetlands. We also explore the potential role of soil seed bank in restoration of drying and saline-alkaline wetlands. Principal Findings Species richness decreased with increase in water level, but there almost no change in seed density. A huge difference exists in species composition of the seed bank among different water levels in all three wetlands, especially between 0 cm and 5 cm and 0 cm and 10 cm. Similarity of species composition between seed bank and plant community was higher in 0 cm water level in drying wetland than in the other two wetlands. The similarity was much higher in 0 cm water level than in 5 cm and 10 cm water levels in all three wetlands. Species composition of the alpine wetland plant community changed significantly after drying and salinization, however, species composition of the seed bank was unchanged regardless of the environment change. Conclusions/Significance Water level greatly affects seed bank recruitment and plant community establishment. Further, different water levels in restored habitats are likely to determine its species composition of the plant community. The seed bank is important in restoration of degraded wetlands. Successful restoration of drying and salinization wetlands could depend on the seed bank. PMID:24984070

  3. Water level fluctuations in an urban pond: Climatic or anthropogenic impact?

    USGS Publications Warehouse

    Benton, S.E.

    2002-01-01

    In 1996, the Illinois State Geological Survey began an investigation of fluctuating water levels in a pond in Cary, Illinois. The cause of the fluctuations appeared to be ground water discharge into a storm sewer recently installed by the Illinois Department of Transportation. However, analysis of climatic data provided an equally likely explanation of the fluctuations. Distinguishing the effect of climatic variations from the effect of the storm sewer was hampered by the lack of antecedent ground water and surface water data. In similar settings, it is recommended that ground water and surface water data be collected prior to initiating any infrastructure improvements.

  4. Persistence of F-specific RNA phages in surface waters from a produce production region along the central coast of California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    F+ RNA coliphages (FRNA) are used to source-track fecal contamination and as surrogates for enteric pathogen persistence in the environment. However, the environmental persistence of FRNA is not clearly understood and thus we evaluated the survival of prototype and environmental isolates of FRNA rep...

  5. Ground-Water Levels in the Kabul Basin, Afghanistan, 2004-2007

    USGS Publications Warehouse

    Akbari, M. Amin; Tahir, Mohammad; Litke, David W.; Chornack, Michael P.

    2007-01-01

    Water levels were monitored in 69 wells in the Kabul Basin, Afghanistan, starting in July 2004 and continuing through March 2007. The monitoring network is composed of existing water-supply wells; therefore, both static and dynamic water levels were recorded. Very little information is available about the construction or completion of the wells, and there are no geologic logs for the wells being monitored. The majority of the wells are completed in Tertiary or Quaternary sediments. Water levels were measured periodically, generally monthly, by engineers from the Afghanistan Geological Survey using 100-meter electric tapes. Well depths in the study area ranged from 4.9 to 160 meters. Water levels below land surface ranged from less than 1.5 to 68 meters, while static water levels ranged from 1.5 to 40 meters. Seasonal water-level fluctuations from September 2005 through May 2006 ranged from less than 1 to 8 meters. Water level trends during the study period showed both increases and decreases. Drawdowns due to pumping ranged from 5 to 25 meters.

  6. Water levels in the Yucca Mountain area, Nevada, 1990--91

    SciTech Connect

    Tucci, P.; O`Brien, G.M.; Burkhardt, D.J.

    1996-07-01

    Water levels were monitored in 27 wells in the Yucca Mountain area, Nevada during 1990--91. Twelve wells were monitored periodically, generally on a monthly basis, and 15 wells representing 24 intervals were monitored hourly. All wells monitor water levels in Tertiary volcanic rocks, except one that monitors levels in paleozoic carbonate rocks. Water levels were measured using calibrated steel tapes and pressure transducers; steel-tape measurements were corrected for mechanical stretch, thermal expansion, and borehole deviation to obtain precise water-level altitudes. Water-level altitudes in the Tertiary volcanic rocks ranged from about 728 meters above sea level east of Yucca Mountain to about 1,035 meters above sea level north of Yucca Mountain. Water-level altitudes in the well monitoring the Paleozoic carbonate rocks varied between 752 and 753 meters above sea level during 1990--91. All data were acquired in accordance with a quality-assurance program to support the reliability of the data.

  7. Stability of low levels of perchlorate in drinking water and natural water samples

    USGS Publications Warehouse

    Stetson, S.J.; Wanty, R.B.; Helsel, D.R.; Kalkhoff, S.J.; Macalady, D.L.

    2006-01-01

    Perchlorate ion (ClO4-) is an environmental contaminant of growing concern due to its potential human health effects, impact on aquatic and land animals, and widespread occurrence throughout the United States. The determination of perchlorate cannot normally be carried out in the field. As such, water samples for perchlorate analysis are often shipped to a central laboratory, where they may be stored for a significant period before analysis. The stability of perchlorate ion in various types of commonly encountered water samples has not been generally examined-the effect of such storage is thus not known. In the present study, the long-term stability of perchlorate ion in deionized water, tap water, ground water, and surface water was examined. Sample sets containing approximately 1000, 100, 1.0, and 0.5 ??g l-1 perchlorate ion in deionized water and also in local tap water were formulated. These samples were analyzed by ion chromatography for perchlorate ion concentration against freshly prepared standards every 24 h for the first 7 days, biweekly for the next 4 weeks, and periodically after that for a total of 400 or 610 days for the two lowest concentrations and a total of 428 or 638 days for the high concentrations. Ground and surface water samples containing perchlorate were collected, held and analyzed for perchlorate concentration periodically over at least 360 days. All samples except for the surface water samples were found to be stable for the duration of the study, allowing for holding times of at least 300 days for ground water samples and at least 90 days for surface water samples. ?? 2006 Elsevier B.V. All rights reserved.

  8. Ground-Water Levels in Huron County, Michigan, January 1996 through December 1996

    USGS Publications Warehouse

    Sweat, M.J.

    1997-01-01

    In 1990, the U.S. Geological Survey (USGS) completed a study of the hydrogeology of Huron County, Michigan (Sweat, 1991). In 1993, Huron County and the USGS entered into an agreement to continue collecting water levels at selected wells throughout Huron County. As part of the agreement, the USGS has provided training and instrumentation for County personnel to measure, on a quarterly basis, the depth to water below the land surface in selected wells. The agreement includes the operation of continuous water-level recorders installed on four wells in Bingham, Fairhaven, Grant and Lake Townships (fig. 1). County personnel make quarterly water-level measurements of 22 other wells. Once each year, County personnel are accompanied by USGS personnel who provide a quality assurance/quality control check of all measurements being made. Precipitation and the altitude of Lake Huron are good indicators of general climatic conditions and, therefore, provide an environmental context for ground-water levels in Huron County. Figure 2 shows the mean monthly water-level altitude of Lake Huron, averaged from measurements made by U.S. Army Corps of Engineers at two sites, and mean monthly precipitation as recorded in Huron County, for the period October 1988 through December 1996. In general, Lake Huron water levels in 1996 were about the same as they were from 1992-94 (NOAA, 1988-96). Precipitation was generally within the normal range, but was lower than 1993 or 1994. Rainfall during May, June, and July was, cumulatively, about 8.5 inches less in 1995 than in 1994. Hydrographs are presented for each of four wells with water-level recorders. Quarterly water-level measurements and range of water levels during 1996 for the other 22 wells are shown graphically and tabulated. In general, water levels in the glaciofluvial aquifer reflect seasonal variations, with maximum depths to water occurring in late summer and early fall and minimum depths to water occurring in late winter and early

  9. The Water Footprint as an indicator of environmental sustainability in water use at the river basin level.

    PubMed

    Pellicer-Martínez, Francisco; Martínez-Paz, José Miguel

    2016-11-15

    One of the main challenges in water management is to determine how the current water use can condition its availability to future generations and hence its sustainability. This study proposes the use of the Water Footprint (WF) indicator to assess the environmental sustainability in water resources management at the river basin level. The current study presents the methodology developed and applies it to a case study. The WF is a relatively new indicator that measures the total volume of freshwater that is used as a production factor. Its application is ever growing in the evaluation of water use in production processes. The calculation of the WF involves water resources (blue), precipitation stored in the soil (green) and pollution (grey). It provides a comprehensive assessment of the environmental sustainability of water use in a river basin. The methodology is based upon the simulation of the anthropised water cycle, which is conducted by combining a hydrological model and a decision support system. The methodology allows the assessment of the environmental sustainability of water management at different levels, and/or ex-ante analysis of how the decisions made in water planning process affect sustainability. The sustainability study was carried out in the Segura River Basin (SRB) in South-eastern Spain. The SRB is among the most complex basins in Europe, given its special peculiarities: competition for the use, overexploitation of aquifers, pollution, alternative sources, among others. The results indicate that blue water use is not sustainable due to the generalised overexploitation of aquifers. They also reveal that surface water pollution, which is not sustainable, is mainly caused by phosphate concentrations. The assessment of future scenarios reveals that these problems will worsen if no additional measures are implemented, and therefore the water management in the SRB is environmentally unsustainable in both the short- and medium-term. PMID:27405519

  10. The Water Footprint as an indicator of environmental sustainability in water use at the river basin level.

    PubMed

    Pellicer-Martínez, Francisco; Martínez-Paz, José Miguel

    2016-11-15

    One of the main challenges in water management is to determine how the current water use can condition its availability to future generations and hence its sustainability. This study proposes the use of the Water Footprint (WF) indicator to assess the environmental sustainability in water resources management at the river basin level. The current study presents the methodology developed and applies it to a case study. The WF is a relatively new indicator that measures the total volume of freshwater that is used as a production factor. Its application is ever growing in the evaluation of water use in production processes. The calculation of the WF involves water resources (blue), precipitation stored in the soil (green) and pollution (grey). It provides a comprehensive assessment of the environmental sustainability of water use in a river basin. The methodology is based upon the simulation of the anthropised water cycle, which is conducted by combining a hydrological model and a decision support system. The methodology allows the assessment of the environmental sustainability of water management at different levels, and/or ex-ante analysis of how the decisions made in water planning process affect sustainability. The sustainability study was carried out in the Segura River Basin (SRB) in South-eastern Spain. The SRB is among the most complex basins in Europe, given its special peculiarities: competition for the use, overexploitation of aquifers, pollution, alternative sources, among others. The results indicate that blue water use is not sustainable due to the generalised overexploitation of aquifers. They also reveal that surface water pollution, which is not sustainable, is mainly caused by phosphate concentrations. The assessment of future scenarios reveals that these problems will worsen if no additional measures are implemented, and therefore the water management in the SRB is environmentally unsustainable in both the short- and medium-term.