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Sample records for dubia daphnids clinch

  1. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Russell, C.L.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of July 22--29, 1993. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field engineering personnel from Clinch River Mile 19.0 and Mile 22.0 on July 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Reference toxicant test information.

  2. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) pilot study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a pilot study during the week of April 22--29, 1993, prior to initiation of CR-ERP Phase 2 Sampling and Analysis activities. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0 and Poplar Creek Kilometer 1.6 on April 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; Reference toxicant test information; and Personnel training documentation.

  3. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1994-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of January 25--February 1, 1994. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected from Clinch River Mile 9.0, Poplar Creek Mile 1.0, and Poplar Creek Mile 2.9 on January 24, 26, and 28. Samples were partitioned and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to fathead minnows; however, toxicity to daphnids was demonstrated in undiluted samples from Poplar Creek Mile 1.0 in testing conducted by TVA based on hypothesis testing of data. Point estimation (IC{sub 25}) analysis of the data, however, showed no toxicity in PCM 1.0 samples. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; Meter calibrations; and Reference toxicant test information.

  4. Clinch River - Environmental Restoration Program (CR-ERP) Study, ambient water toxicity. Final report, October 21, 1993--October 28, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of October 21-28, 1993, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Due to serious reproduction/embryo abortion problems with the TVA daphnid cultures, TVA conducted tests during this study period using only fathead minnows. A split sample test using daphnids only will be scheduled during 1994 as a substitute for this study period. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 2.9, Mile 4.3, and Mile 5.1 on October 20, 22, and 25. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) in testing conducted by TVA.

  5. Clinch River - Environmental Restoration Program (CR-ERP) pilot study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a pilot study during the week of April 22-29, 1993, prior to initiation of CR-ERP Phase II Sampling and Analysis activities as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0 and Poplar Creek Kilometer 1.6 on April 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA.

  6. Clinch River - Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Russell, C.L.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of July 22-29, 1993, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 19.0 and Mile 22.0 on July 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA.

  7. Static renewal tests using Pimephales promelas (fathead minnows). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of October 21--28, 1993. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Due to serious reproduction/embryo abortion problems with the TVA daphnid cultures, TVA conducted tests during this study period using only fathead minnows. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 2.9, Mile 4.3, and Mile 5.1 on October 20, 22, and 25. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Reference toxicant test information.

  8. Clinch River - Environmental Restoration Program (CR-ERP) study, Ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of January 25-February 1, 1994, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0, Poplar Creek Mile 1.0, and Poplar Creek Mile 2.9 on January 24, 26, and 28. Samples were partitioned (split) and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to fathead minnows; however, toxicity to daphnids (significantly reduced reproduction) was demonstrated in undiluted samples from Poplar Creek Mile 1.0 in testing conducted by TVA based on hypothesis testing of data. Point estimation (IC{sub 25}) analysis of the data, however, showed no toxicity in PCM 1.0 samples.

  9. Clinch River - Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of April 14-21, 1994, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 4.3, Poplar Creek Mile 5.1, and Poplar Creek Mile 6.0 on April 13, 15, and 18. Samples were partitioned (split) and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to daphnids in undiluted samples; however, toxicity to fathead minnows (significantly reduced survival) was demonstrated in undiluted samples from Poplar Creek Miles 4.3 and 6.0 in testing conducted by TVA based on hypothesis testing of data. Daphnid reproduction was significantly less than controls in 50 percent dilutions of samples from Poplar Creek Miles 4.3 and 6.0, while no toxicity to fathead minnows was shown in diluted (50 percent) samples.

  10. Clinch River project: Sediment contaminants in the Lower Clinch River

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Sediment samples from three mainstem and seven tributary sites in the Clinch River Basin were analyzed for 21 organochlorine compounds, 19 metals, total volatile...

  11. 40 CFR 797.1330 - Daphnid chronic toxicity test.

    Science.gov (United States)

    2010-07-01

    ... daphnids except for minor activity of the appendages. (7) Loading means the ratio of daphnid biomass (grams... acceptable if likely degradation products of the test substance, such as hydrolysis and oxidation products..., pH), and a description of any pretreatment. (4) Detailed information about the daphnids used...

  12. Effects of sludge filtrate on the survival and reproduction of Ceriodaphnia dubia

    Science.gov (United States)

    Veerina, S.S.; Parker, N.C.; Fedler, C.B.

    2002-01-01

    The objective of this study was to determine if the runoff from croplands fertilized with municipal sludge was toxic to aquatic biota and, therefore, a potential threat to either public health or the environment. Seven-day bioassays with Ceriodaphnia dubia showed that the No-Observed-Effect-Concentration (NOEC) was 24 g/L and the Lowest-Observed-Effect-Concentration (LOEC) for survival was 30 g/L for soil samples treated with 35.2 metric tonnes (MT)/ha of municipal sludge. For soil samples treated with 0 and 17.6 MT/ha of sludge, the survival rates of C. dubia were not significantly affected at concentrations of 6-30 g/L of soil. Reproduction was suppressed by 25% when daphnids were exposed to 3.3 g/L concentration of soil treated with sludge at 35.2 MT/ha. A 50% suppression of reproduction occurred when daphnids were exposed to 15 g/L concentration of soil treated with sludge at 17.6MT/ha. A sludge application rate of 17.6MT/ha suppressed reproduction at a treatment concentration of 18g/L. These data indicate that the runoff from agricultural lands treated with municipal sludge has the potential to affect reproduction in daphnids and, therefore, the environment through the aquatic food chain.

  13. Trophic transfer potential of aluminium oxide nanoparticles using representative primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia)

    Energy Technology Data Exchange (ETDEWEB)

    Pakrashi, Sunandan; Dalai, Swayamprava; Chandrasekaran, Natarajan; Mukherjee, Amitava, E-mail: amit.mookerjea@gmail.com

    2014-07-01

    Highlights: • Trophic transfer of alumina nanoparticles using Chlorella ellipsoides and Ceriodaphnia dubia. • Subtle alterations in the feeding behaviour of the daphnids. • Disruption the energy flow through the food chain. • Transmission electron microscopy validated the disrupted feeding behaviour. - Abstract: The transfer of nanoparticles through the food chain can lead to bioaccumulation and biomagnification resulting in a long term negative impact on the ecosystem functions. The primary objective of this study was evaluation of aluminium oxide nanoparticles transfer from primary producers to primary consumers. A simple set up consisting of a primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia) was used. Here, C. ellipsoides were exposed to the varying concentrations of the nanoparticles ranging from 20 to 120 μg/mL (196 to 1176 μM) for 48 h and the infested algal cells were used as the feed to C. dubia. The bioaccumulation of the nanoparticles into the daphnids was noted and the biomagnification factors were computed. The exposure was noted to cause subtle alterations in the feeding behaviour of the daphnids. This might have long term consequences in the energy flow through the food chain. The reproductive behaviour of the daphnids remained unaffected upon exposure to nanoparticle infested algal feed. Distinct observations at ultra-structural scale using transmission electron microscopy provided visual evidences for the disrupted feeding behaviour upon exposure to nanoparticle treated algae. Internalization of nanoparticle like inclusion bodies in the intracellular space of algae was also detected. The findings were further substantiated by a detailed analysis of hydrodynamic stability, bioavailability and dissolution of ions from the nanoparticles over the exposure period. Altogether, the study brings out the first of its kind of observation of trophic transfer potential/behaviour of aluminium oxide nanoparticles and

  14. Influences of water chemistry on the acute toxicity of lead to Pimephales promelas and Ceriodaphnia dubia.

    Science.gov (United States)

    Mager, Edward M; Esbaugh, Andrew J; Brix, Kevin V; Ryan, Adam C; Grosell, Martin

    2011-01-01

    The acute toxicity of lead (Pb) was examined for fathead minnows (Pimephales promelas; 96-h) and daphnids (Ceriodaphnia dubia; 48-h) in waters modified for hardness (as CaSO₄), dissolved organic carbon (DOC; as Aldrich humic acid) and alkalinity (as NaHCO₃) for parameterization of an acute freshwater biotic ligand model (BLM). Additionally, acute (96-h) and chronic (30-d) bioassays were performed for P. promelas to more clearly define the influence of pH (5.5-8.3) on Pb toxicity as modified by addition of HCl or NaOH using an automated titration system. Results indicate that Ca(2+) is protective against acute Pb toxicity to P. promelas but not C. dubia. Strong protection was afforded by DOC and NaHCO(3) against acute Pb toxicity to P. promelas, whereas milder protection was observed for C. dubia with both parameters. Dissolved Pb LC50s from the P. promelas pH bioassays revealed a complex effect of pH on Pb toxicity, likely explained in part by Pb speciation and the competitive interaction of H(+) with ionic Pb(2+). Chronic pH bioassays also demonstrated that 30-d growth is not impaired in fathead minnows at relevant Pb concentrations. The findings reported herein suggest that development of separate BLMs for P. promelas and C. dubia should be considered.

  15. Modeling strategy for clinched joints in assemblies

    Science.gov (United States)

    Breda, A.; Coppieters, S.; Debruyne, D.

    2016-08-01

    Clinching is a mechanical joining technique which involves severe local plastic deformation of two or more metal sheet parts resulting in a permanent mechanical interlock. Today, it is a reliable joining technique used in automotive, HVAC and general steel constructions whilst still gaining interest. As it is not computationally feasible to include detailed sub models of these type of joints in FE simulations of real-life clinched assemblies, this paper proposes a methodology to represent these connections with simplified elements. In order to calibrate the parameters governing the equivalent model, a simple shear lap and pullout test is used. This methodology is applied to clinched configurations and validated using a modified Arcan test in which both shear and pull-out loads are considered.

  16. Study of ecotoxicity of silver nanoparticles using daphnids

    Science.gov (United States)

    Kustov, L. M.; Abramenko, N. B.

    2016-12-01

    Silver nanoparticles have been prepared and tested for their ecotoxicity using daphnids as a hydrobiotic test. The toxicity was supposed to originate from Ag+ ions released into the aqueous solution. Also, the toxicity of the stabilizing agent was found to be comparable to that of silver nanoparticles.

  17. 40 CFR 797.1300 - Daphnid acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... ratio of daphnid biomass (grams, wet weight) to the volume (liters) of test solution in a test chamber... oxidation products, give positive or negative interferences which cannot be systematically identified and...., conductivity, hardness, pH, etc.) and a description of any pretreatment. (4) Detailed information about...

  18. Trophic transfer potential of aluminium oxide nanoparticles using representative primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia).

    Science.gov (United States)

    Pakrashi, Sunandan; Dalai, Swayamprava; Chandrasekaran, Natarajan; Mukherjee, Amitava

    2014-07-01

    The transfer of nanoparticles through the food chain can lead to bioaccumulation and biomagnification resulting in a long term negative impact on the ecosystem functions. The primary objective of this study was evaluation of aluminium oxide nanoparticles transfer from primary producers to primary consumers. A simple set up consisting of a primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia) was used. Here, C. ellipsoides were exposed to the varying concentrations of the nanoparticles ranging from 20 to 120μg/mL (196 to 1176μM) for 48h and the infested algal cells were used as the feed to C. dubia. The bioaccumulation of the nanoparticles into the daphnids was noted and the biomagnification factors were computed. The exposure was noted to cause subtle alterations in the feeding behaviour of the daphnids. This might have long term consequences in the energy flow through the food chain. The reproductive behaviour of the daphnids remained unaffected upon exposure to nanoparticle infested algal feed. Distinct observations at ultra-structural scale using transmission electron microscopy provided visual evidences for the disrupted feeding behaviour upon exposure to nanoparticle treated algae. Internalization of nanoparticle like inclusion bodies in the intracellular space of algae was also detected. The findings were further substantiated by a detailed analysis of hydrodynamic stability, bioavailability and dissolution of ions from the nanoparticles over the exposure period. Altogether, the study brings out the first of its kind of observation of trophic transfer potential/behaviour of aluminium oxide nanoparticles and its probable impacts on the energy flow in the fresh water aquatic ecosystem.

  19. Nomina dubia and available names.

    Science.gov (United States)

    Melville, R V

    1980-01-01

    The availability or non-availability of a name is a question of historical fact. A name once made available under the International Code of Zoological Nomenclature can be rendered unavailable only by use of the plenary powers of the Commission. The question whether a name is a nomen dubium or not is a matter of taxonomic judgement. The difficulty with the Sarcocystinae discussed by Frenkel et al. (1979) stems from the fact that, under the present provisions of the Code, it is not possible to designate for the species concerned types that will serve any useful function. The Commission is now considering changes to the Code proposed to remedy this defect in a general, legislative way. It will not, as a matter of general practice, entertain proposals for the suppression of names merely because they are considered to be nomina dubia. The application submitted by Professor Frenkel and his collegaues will nevertheless be published in the Bulletin of Zoological Nomenclature so that the Commission can, if necessary, deliver a ruling on it before the new edition of the Code has appeared.

  20. Stamping automotive parts with clinch nut process

    Science.gov (United States)

    Bałon, Paweł; Świntoniowski, Andrzej

    2013-12-01

    In this paper authors present joining by forming method for screws and nuts that is more and more used nowadays. They aim to show its basic advantages and problems that occurred during the conducted researches. They concerned both joining process as well as strength tests of a sheet and nuts junction. That process is very often carried out for UHSS and AHSS steels which usually contain decreased plastic properties and increased strength. It usually causes a problem to set up the self-clinching process. Currently, there are a few companies specialising only in this kind of processes, however correct designing of such tool requires taking into account many factors such as choose of joining method by forming and proper connector type.

  1. Joining three car body steel sheets by clinching method

    Science.gov (United States)

    Kaščák, Ľuboš; Spišák, Emil; Majerníková, Jana

    2016-12-01

    The optimization of a car body in terms of cost can be achieved by using different materials in various positions of the car in order to utilize specific properties of each different material. Resistance spot welding is the most used method of joining in car body production, but it is not always easy or even possible to join some combination of materials by this method. Clinching is an alternative method to spot welding, as a combination of drawing and forming. The research is focused on the evaluation of clinched joints' properties using shearing test and metallographic observation of material structure.

  2. Predicting the quality of clinch joints using FEM

    NARCIS (Netherlands)

    Rietman, Bert; Goretti Doig, Maria; Weiher, Jochen

    2001-01-01

    In the last decade clinch joining has become established as a cost-effective alternative to spot welding. Its develompent was brought on by the ongoing trend towards lightweight structures especially in the automotive insdustry. Choosing the tool which gives the best performance for a newly develope

  3. The Clinch Bend Regional Industrial Site and economic development opportunities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This effort focuses initially on the Clinch Bend site. Other sites and developable tracts of land are identified with the assistance of communities in proximity to Oak Ridge, the State of Tennessee, and others, and compared with the projected site requirements for large industrial facilities.

  4. Propiedades prooxidantes del camu camu (Myrciaria dubia

    Directory of Open Access Journals (Sweden)

    Henry Guija

    2005-12-01

    Full Text Available Objetivo: Determinar el efecto del ion férrico sobre las propiedades prooxidantes del camu camu (Myrciaria dubia. Diseño: Estudio analítico, experimental, prospectivo y longitudinal. Materiales y Métodos: Se ha evaluado las propiedades prooxidantes del camu camu (Myrciaria dubia, fruto caracterizado por tener un elevado contenido de vitamina C, frente a Fe(III, etilendiamino tetraacético (EDTA, tiourea y manitol. Resultados: El camu camu en presencia de Fe-III en tampón fosfato a pH 7,4 incrementó notablemente la generación de radicales libres a través de una cinética de saturación, efecto que fue dependiente de la concentración del metal. La presencia de tiourea o manitol, compuestos de conocida acción antioxidante, inhibieron la formación de radicales libres, en cambio el EDTA lo incrementó. Conclusión: El camu camu incrementa la generación de radicales libres en presencia de Fe(III y EDTA.

  5. Scale Insects (Hemiptera: Coccoidea) on Myrciaria dubia (Myrtaceae) in Brazil.

    Science.gov (United States)

    Wolff, V R S; Kondo, T; Peronti, A L B G; Noronha, A C S

    2016-06-01

    Commercial cultivation of the fruit tree Myrciaria dubia (Myrtaceae) is being developed in Brazil but phytophagous insects, including scale insects (Hemiptera: Coccoidea), can become pests in plantations. The coccids Ceroplastes jamaicensis White, Coccus viridis (Green), Parasaissetia nigra (Nietner), Pseudokermes vitreus (Cockerell) (Coccidae), and the diaspidid Pseudaonidia trilobitiformis (Green) were collected on M. dubia in the municipality of Belém and Tomé-Açu, state of Pará (PA), metropolitan and Northeast Pará mesoregions, Brazil. A key to species of Coccoidea recorded on M. dubia, based on adult females, is provided. Photographs for all scale insects reported on M. dubia are provided. Ceroplastes jamaicensis is recorded for the first time for Brazil and is herein reported for the first time associated with this host.

  6. Danos de Conotrachelus dubiae (Coleoptera: curculionidae em frutos de camu-camu (Myrciaria dubia na Amazônia Central Damage of camu-camu (Myrciaria dubia fruits by Conotrachelus dubiae (Coleoptera: curculionidae in Central Amazonia

    Directory of Open Access Journals (Sweden)

    Sidney Alberto do Nascimento Ferreira

    2003-12-01

    Full Text Available No Brasil, a ocorrência de Conotrachelus dubiae O'Brien, 1995 (Coleoptera: Curculionidae em camu-camu [Myrciaria dubia (H.B.K. McVaugh, Myrtaceae] tinha sido constatada somente em populações naturais. Relata-se sua ocorrência em um cultivo experimental, onde se avaliou os danos de C. dubiae em frutos de camu-camu, em diferentes graus de amadurecimento, entre 1999 e 2003. Os danos causados pela larva aumentaram com o amadurecimento dos frutos, havendo maior comprometimento da polpa do fruto (30 a 90% do que das sementes (7%. A incidência desse inseto pode implicar em perdas quantitativas significativas na produção de camu-camu.In Brazil, the occurrence of Conotrachelus dubiae O'Brien, 1995 (Coleoptera: Curculionidae in camu-camu [Myrciaria dubia (H.B.K. McVaugh, Myrtaceae] had only been verified in natural populations. This report describes its occurrence in an experimental cultivation, where damage of camu-camu fruits by C. dubiae at different ripening stages was evaluated between 1999 and 2003. The damage caused by the larva increased with the degree of ripening of the fruits, with greater damage of fruit pulp (30 to 90% than to seeds (7%. The incidence of this insect may cause significant quantitative losses in the camu-camu production.

  7. Utility of population models to reduce uncertainty and increase value relevance in ecological risk assessments of pesticides: an example based on acute mortality data for daphnids.

    Science.gov (United States)

    Hanson, Niklas; Stark, John D

    2012-04-01

    Traditionally, ecological risk assessments (ERA) of pesticides have been based on risk ratios, where the predicted concentration of the chemical is compared to the concentration that causes biological effects. The concentration that causes biological effect is mostly determined from laboratory experiments using endpoints on the level of the individual (e.g., mortality and reproduction). However, the protection goals are mostly defined at the population level. To deal with the uncertainty in the necessary extrapolations, safety factors are used. Major disadvantages with this simplified approach is that it is difficult to relate a risk ratio to the environmental protection goals, and that the use of fixed safety factors can result in over- as well as underprotective assessments. To reduce uncertainty and increase value relevance in ERA, it has been argued that population models should be used more frequently. In the present study, we have used matrix population models for 3 daphnid species (Ceriodaphnia dubia, Daphnia magna, and D. pulex) to reduce uncertainty and increase value relevance in the ERA of a pesticide (spinosad). The survival rates in the models were reduced in accordance with data from traditional acute mortality tests. As no data on reproductive effects were available, the conservative assumption that no reproduction occurred during the exposure period was made. The models were used to calculate the minimum population size and the time to recovery. These endpoints can be related to the European Union (EU) protection goals for aquatic ecosystems in the vicinity of agricultural fields, which state that reversible population level effects are acceptable if there is recovery within an acceptable (undefined) time frame. The results of the population models were compared to the acceptable (according to EU documents) toxicity exposure ratio (TER) that was based on the same data. At the acceptable TER, which was based on the most sensitive species (C. dubia

  8. Sarcocystinae: nomina dubia and available names.

    Science.gov (United States)

    Frenkel, J K; Heydorn, A O; Mehlhorn, H; Rommel, M

    1979-02-28

    Examination of the original descriptions of the species of Sarcocystis in cattle, sheep, and swine, and of isosporid oocysts shed sporulated by dogs, cats, man, and other carnivores, has shown that it is not possible in most instances to identify unambiguously recently recognized taxa. The original descriptions are insufficient, and because no type specimens exist, could apply to two or more of the presently recognized taxa. We consider the following nomina dubia: Sarcocystis hirsuta S. miescheriana S. tenella S. cruzi S. bertrami Isospora bigemina (S. bigemina) I. hominis (S. hominis) I. buteonis (Frenkelia buteonis) Because the former type species, Sarcocystis miescheriana, is an indeterminate nomen dubium, we are proposing S. muris as the new type species. Historically, it was the first species described clearly and unambiguously even in the light of present knowledge, and the stages of its life cycle are probably completely known; it was the second species to be named. Old and recent descriptions are reviewed, and definitions are proposed for the following taxa: S. bovifelis S. bovicanis S. bovihominis S. ovifelis S. ovicanis S. muris (type species) S. suihominis S. suicanis S. equicanis Frenkelia microti F. glareoli for which neotypes will be prepared and deposited with designated institutions and curators. A new subfamily, Cystoisosporinae, is created.

  9. Technological aspects of manufacturing and numerical modelling of clinch-adhesive joints

    CERN Document Server

    Sadowski, Tomasz; Golewski, Przemysław

    2015-01-01

    This short book describes the basic technological aspects involved in the creation of purely clinch and clinch-adhesive joints made of different types of adherent materials and employing different joining technologies. Basic parameters that need to be taken into account in the design process are also presented, while a comparison of experimental testing of the hybrid joint with simple clinching for a combination of different joining materials underlines the advantages of opting for hybrid joints. The book’s conclusions will facilitate the practical application of this new fastening technology.

  10. Toxicity of manganese to Ceriodaphnia dubia and Hyalella azteca

    Science.gov (United States)

    Lasier, P.J.; Winger, P.V.; Bogenrieder, K.J.

    2000-01-01

    Manganese is a toxic element frequently overlooked when assessing toxicity of effluents, sediments and pore waters. Manganese can be present at toxic levels in anoxic solutions due to its increased solubility under chemically-reducing conditions, and it can remain at those levels for days in aerated test waters due to slow precipitation kinetics. Ceriodaphnia dubia and Hyalella azteca are freshwater organisms often used for toxicity testing and recommended for assessments of effluents and pore waters. Lethal and reproductive-inhibition concentrations of Mn were determined for C. dubia in acute 48h tests and chronic 3-brood tests using animals Manganese concentrations were measured analytically at test initiation and after 96 h for calculations of toxicity endpoints and determinations of Mn precipitation during the tests. Minimal amounts of Mn (below 3%) precipitated within 96 h. LC50s determined for H. azteca progressively increased from 3.0 to 8.6 to 13.7 mg Mn/L in soft, moderately-hard and hard waters, respectively. The tolerance of C. dubia to Mn was not significantly different between moderately-hard and hard waters, but was significantly lower in soft water. There was no significant difference in Mn sensitivity between the ages of C. dubia tested. Acute LC50 values for C. dubia averaged 6.2, 14.5 and 15.2 mg Mn/L and chronic IC50 values averaged 3.9, 8.5 and 11.5 mg Mn/L for soft, moderately-hard and hard waters, respectively. Manganese toxicity should be considered when assessing solutions with concentrations near these levels.

  11. Regulation and dysregulation of vitellogenin mRNA accumulation in daphnids (Daphnia magna)

    Energy Technology Data Exchange (ETDEWEB)

    Hannas, Bethany R.; Wang, Ying H.; Thomson, Susanne; Kwon, Gwijun; Li Hong [Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695-7633 (United States); LeBlanc, Gerald A., E-mail: Gerald_LeBlanc@ncsu.edu [Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695-7633 (United States)

    2011-01-25

    The induction of vitellogenin in oviparous vertebrates has become the gold standard biomarker of exposure to estrogenic chemicals in the environment. This biomarker of estrogen exposure also has been used in arthropods, however, little is known of the factors that regulate the expression of vitellogenin in these organisms. We investigated changes in accumulation of mRNA products of the vitellogenin gene Vtg2 in daphnids (Daphnia magna) exposed to a diverse array of chemicals. We further evaluated the involvement of hormonal factors in the regulation of vitellogenin expression that may be targets of xenobiotic chemicals. Expression of the Vtg2 gene was highly responsive to exposure to various chemicals with an expression range spanning approximately four orders of magnitude. Chemicals causing the greatest induction were piperonyl butoxide, chlordane, 4-nonylphenol, cadmium, and chloroform. Among these, only 4-nonylphenol is recognized to be estrogenic. Exposure to several chemicals also suppressed Vtg2 mRNA levels, as much as 100-fold. Suppressive chemicals included cyproterone acetate, acetone, triclosan, and atrazine. Exposure to the estrogens diethylstilbestrol and bisphenol A had little effect on vitellogenin mRNA levels further substantiating that these genes are not induced by estrogen exposure. Exposure to the potent ecdysteroids 20-hydroxyecdysone and ponasterone A revealed that Vtg2 was subject to strong suppressive control by these hormones. Vtg2 mRNA levels were not significantly affected from exposure to several juvenoid hormones. Results indicate that ecdysteroids are suppressors of vitellogenin gene expression and that vitellogenin mRNA levels can be elevated or suppressed in daphnids by xenobiotics that elicit antiecdysteroidal or ecdysteroidal activity, respectively. Importantly, daphnid Vtg2 is not elevated in response to estrogenic activity.

  12. Summary of preliminary contaminant impacts investigations in the Clinch River Basin, Virginia, using multiple bioassessment techniques

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 1992 multiple investigations were performed to collect preliminary information to direct future studies aimed at characterizing contaminant problems in the Clinch...

  13. An Experimental Study on Micro Clinching of Metal Foils with Cutting by Laser Shock Forming

    OpenAIRE

    Xiao Wang; Cong Li; Youjuan Ma; Zongbao Shen; Xianqing Sun; Chaofei Sha; Shuai Gao; Liyin Li; Huixia Liu

    2016-01-01

    This paper describes a novel technique for joining similar and dissimilar metal foils, namely micro clinching with cutting by laser shock forming. A series of experiments were conducted to study the deformation behavior of single layer material, during which many important process parameters were determined. The process window of the 1060 pure aluminum foils and annealed copper foils produced by micro clinching with cutting was analyzed. Moreover, similar material combination (annealed copper...

  14. Exposure to Cerium Dioxide Nanoparticles Differently Affect Swimming Performance and Survival in Two Daphnid Species

    Science.gov (United States)

    Artells, Ester; Issartel, Julien; Auffan, Mélanie; Borschneck, Daniel; Thill, Antoine; Tella, Marie; Brousset, Lenka; Rose, Jérôme; Bottero, Jean-Yves; Thiéry, Alain

    2013-01-01

    The CeO2 NPs are increasingly used in industry but the environmental release of these NPs and their subsequent behavior and biological effects are currently unclear. This study evaluates for the first time the effects of CeO2 NPs on the survival and the swimming performance of two cladoceran species, Daphnia similis and Daphnia pulex after 1, 10 and 100 mg.L−1 CeO2 exposures for 48 h. Acute toxicity bioassays were performed to determine EC50 of exposed daphnids. Video-recorded swimming behavior of both daphnids was used to measure swimming speeds after various exposures to aggregated CeO2 NPs. The acute ecotoxicity showed that D. similis is 350 times more sensitive to CeO2 NPs than D. pulex, showing 48-h EC50 of 0.26 mg.L−1 and 91.79 mg.L−1, respectively. Both species interacted with CeO2 NPs (adsorption), but much more strongly in the case of D. similis. Swimming velocities (SV) were differently and significantly affected by CeO2 NPs for both species. A 48-h exposure to 1 mg.L−1 induced a decrease of 30% and 40% of the SV in D. pulex and D. similis, respectively. However at higher concentrations, the SV of D. similis was more impacted (60% off for 10 mg.L−1 and 100 mg.L−1) than the one of D. pulex. These interspecific toxic effects of CeO2 NPs are explained by morphological variations such as the presence of reliefs on the cuticle and a longer distal spine in D. similis acting as traps for the CeO2 aggregates. In addition, D. similis has a mean SV double that of D. pulex and thus initially collides with twice more NPs aggregates. The ecotoxicological consequences on the behavior and physiology of a CeO2 NPs exposure in daphnids are discussed. PMID:23977004

  15. Development of single-action,two-step clinching system using finite element analysis

    Institute of Scientific and Technical Information of China (English)

    Seong-Wook LEE; Tae-Hyung KIM; Geun-Jo HAN

    2009-01-01

    Traditional manufacturing processes for bending and combining the upper and lower heat insulation plates for a car catalytic converter need two kinds of bending dies. This study was carried out to develop a single-action, two-step clinching system for clinching heat insulation plates. To design the operating mechanism for this clinching system, finite element analysis was used to estimate the bending load needed and to predict the bent shape of the heat insulation plate. Then a recovery and cushioning system was designed for the bending die. It is expected that this new process will improve the manufacturing quality of heat insulation plates and will reduce manufacturing cost. And a higher value-added technique for mold and pressing systems was introduced.

  16. Mechanical Properties Prediction of the Mechanical Clinching Joints Based on Genetic Algorithm and BP Neural Network

    Institute of Scientific and Technical Information of China (English)

    LONG Jiangqi; LAN Fengchong; CHEN Jiqing; YU Ping

    2009-01-01

    For optimal design of mechanical clinching steel-aluminum joints, the back propagation (BP) neural network is used to research the mapping relationship between joining technique parameters including sheet thickness, sheet hardness, joint bottom diameter etc., and mechanical properties of shearing and peeling in order to investigate joining technology between various material plates in the steel-aluminum hybrid structure car body. Genetic algorithm (GA) is adopted to optimize the back-propagation neural network connection weights. The training and validating samples are made by the BTM(R) Tog-L-Loc system with different technologic parameters. The training samples' parameters and the corresponding joints' mechanical properties are supplied to the artificial neural network (ANN) for training. The validating samples' experimental data is used for checking up the prediction outputs. The calculation results show that GA can improve the model's prediction precision and generalization ability of BP neural network. The comparative analysis between the experimental data and the prediction outputs shows that ANN prediction models after training can effectively predict the mechanical properties of mechanical clinching joints and prove the feasibility and reliability of the intelligent neural networks system when used in the mechanical properties prediction of mechanical clinching joints. The prediction results can be used for a reference in the design of mechanical clinching steel-aluminum joints.

  17. Antibacterial activity of Myrciaria dubia (Camu camu against Streptococcus mutans and Streptococcus sanguinis

    Directory of Open Access Journals (Sweden)

    Rosella Camere-Colarossi

    2016-09-01

    Conclusions: The experimental findings demonstrated the antibacterial effect of the methanol extract of M. dubia against S. mutans and S. sanguinis. These extracts were not cytotoxic at high concentrations.

  18. Fundamental studies on a novel die concept for round-point shear-clinching

    Science.gov (United States)

    Hörhold, Réjane; Müller, Martin; Merklein, Marion; Meschut, Gerson

    2016-10-01

    A newly-developed round-point shear-clinching technology could increase the use of different materials like well formable aluminium and hardly formable ultra-high-strength steels (UHSS). This innovative technology joins in a single-stage process without any pilot-hole, surface pre-treatment or auxiliary joining part. The combination of an inner and outer punch realises an indirect cutting operation of the die-sided material, whereas the punch-sided material remains unharmed. The current die-sided tool set acts as a cutting die and enables a radial extrusion of the punch-sided material after being drawn though the created hole in the UHSS. The die has a fixed die depth. After ejecting the joined components, the slug has to be removed from the top of the spring-loaded anvil. The novel die concept investigated in this paper offers the possibility to push the slug continuously through the die in the joining direction. The removed slugs remain inside the die, so manual removal is unnecessary. The one-parted tool is supposed to be more robust than the multi-parted one that is currently used. This paper represents the task to evaluate the geometry of a useful shear-clinching die concept. To reduce the experimental effort, FEM should assist the development of the most promising approach. To quantify the success, conventional shear-clinching with opening die acts as a reference. The results show the high potential and the raison d'être of shear-clinching technologies as a mechanical joining technology for future multimaterial applications especially for UHSS.

  19. Conceptual design of the Clinch River Breeder Reactor spent-fuel shipping cask

    Energy Technology Data Exchange (ETDEWEB)

    Pope, R B; Diggs, J M [eds.

    1982-04-01

    Details of a baseline conceptual design of a spent fuel shipping cask for the Clinch River Breeder Reactor (CRBR) are presented including an assessment of shielding, structural, thermal, fabrication and cask/plant interfacing problems. A basis for continued cask development and for new technological development is established. Alternates to the baseline design are briefly presented. Estimates of development schedules, cask utilization and cost schedules, and of personnel dose commitments during CRBR in-plant handling of the cask are also presented.

  20. An Experimental Study on Micro Clinching of Metal Foils with Cutting by Laser Shock Forming

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    2016-07-01

    Full Text Available This paper describes a novel technique for joining similar and dissimilar metal foils, namely micro clinching with cutting by laser shock forming. A series of experiments were conducted to study the deformation behavior of single layer material, during which many important process parameters were determined. The process window of the 1060 pure aluminum foils and annealed copper foils produced by micro clinching with cutting was analyzed. Moreover, similar material combination (annealed copper foils and dissimilar material combination (1060 pure aluminum foils and 304 stainless steel foils were successfully achieved. The effect of laser energy on the interlock and minimum thickness of upper foils was investigated. In addition, the mechanical strength of different material combinations joined by micro clinching with cutting was measured in single lap shearing tests. According to the achieved results, this novel technique is more suitable for material combinations where the upper foil is thicker than lower foil. With the increase of laser energy, the interlock increased while the minimum thickness of upper foil decreased gradually. The shear strength of 1060 pure aluminum foils and 304 stainless steel foils combination was three times as large as that of 1060 pure aluminum foils and annealed copper foils combination.

  1. An Experimental Study on Micro Clinching of Metal Foils with Cutting by Laser Shock Forming.

    Science.gov (United States)

    Wang, Xiao; Li, Cong; Ma, Youjuan; Shen, Zongbao; Sun, Xianqing; Sha, Chaofei; Gao, Shuai; Li, Liyin; Liu, Huixia

    2016-07-13

    This paper describes a novel technique for joining similar and dissimilar metal foils, namely micro clinching with cutting by laser shock forming. A series of experiments were conducted to study the deformation behavior of single layer material, during which many important process parameters were determined. The process window of the 1060 pure aluminum foils and annealed copper foils produced by micro clinching with cutting was analyzed. Moreover, similar material combination (annealed copper foils) and dissimilar material combination (1060 pure aluminum foils and 304 stainless steel foils) were successfully achieved. The effect of laser energy on the interlock and minimum thickness of upper foils was investigated. In addition, the mechanical strength of different material combinations joined by micro clinching with cutting was measured in single lap shearing tests. According to the achieved results, this novel technique is more suitable for material combinations where the upper foil is thicker than lower foil. With the increase of laser energy, the interlock increased while the minimum thickness of upper foil decreased gradually. The shear strength of 1060 pure aluminum foils and 304 stainless steel foils combination was three times as large as that of 1060 pure aluminum foils and annealed copper foils combination.

  2. Fingeriana dubia gen. nov. e sp. nov. de Cicadellini (Hemiptera, Auchenorrhyncha, Cicadellidae do sudeste e sul do Brasil Fingeriana dubia gen. nov. and sp. nov. of Cicadellini (Hemiptera, Auchenorrhyncha, Cicadellidae from Southeast and South of Brazil

    Directory of Open Access Journals (Sweden)

    Rodney Ramiro Cavichioli

    2003-06-01

    Full Text Available New genus and new species of Cicadellini are proposed: Fingeriana dubia occurs at the citrus and coffee culture. The new genera is similar with Nielsonia Young, 1977 but, the shaft of the adeagus of the Fingeriana dubia is symmetrical with a basal unpaired process asymmetrical and plates narrowly triangular as long as pygofer.

  3. Chronic toxicity of silver nitrate to Ceriodaphnia dubia and Daphnia magna, and potential mitigating factors.

    Science.gov (United States)

    Naddy, Rami B; Gorsuch, Joseph W; Rehner, Anita B; McNerney, Gina R; Bell, Russell A; Kramer, James R

    2007-08-15

    We investigated the chronic toxicity of Ag, as silver nitrate, using two freshwater aquatic cladoceran species, Ceriodaphnia dubia and Daphnia magna, to generate data for the development of a chronic ambient water quality criterion for Ag. Preliminary studies with C. dubia showed variable results which were related to the equilibration time between food and silver. Follow-up testing was conducted using a 3h equilibration time, which stabilized dissolved Ag concentrations and the toxicity of Ag(+). Results with C. dubia conducted individually (1 per cup, n=10) and in mass (30 per chamber, n=2) gave similar results once similar standardized equilibration times were used. The maximum acceptable toxicant concentration (MATC) of Ag to C. dubia and D. magna was 9.61 and 3.00microg dissolved Ag/L, respectively. The chronic toxicity of Ag(+) to C. dubia was also evaluated in the presence of: (1) dissolved organic carbon (DOC) and (2) sulfide. The addition of DOC (0.4mg/L) resulted in a approximately 50% decrease in toxicity while the addition of sulfide (75.4nM) deceased toxicity by 42%. Whole-body Ag concentration in D. magna was positively correlated with increased levels of Ag exposure, however; we observed a non-statistical decrease in whole-body Na levels, an estimator of sodium homeostasis.

  4. The complete mitochondrial genomes of Opisthoplatia orientalis and Blaptica dubia (Blattodea: Blaberidae).

    Science.gov (United States)

    Tian, Xiaoxuan; Ma, Guangyin; Cui, Ying; Dong, Pengzhi; Zhu, Yan; Gao, Xiumei

    2017-01-01

    The first complete mitochondrial genome in Blaberidae has been reported in this research. Opisthoplatia orientalis (Blaberidae, Epilamprinae) known as ground cockroach with golden edge is distributed in East and South Asia and widely used for thrombolytic therapy in China. Meanwhile, Blaptica dubia (Blaberidae, Blaberinae) has been adopted as feeder insect for various kinds of pets all over the world. In the present study, we investigated the complete mitochondrial genome of O. orientalis and B. dubia, and the mitogenome is 18 724  and 17 340 bp in length, respectively. The circular molecule consists of 13 protein coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a non-coding control region, with an AT content of 75.7% for O. orientalis and 72.8% for B. dubia. A preliminary phylogenetic analysis has been carried out with 11 related species and the status of these two species is further confirmed.

  5. Anodonta imbecillis QA Test 4, Clinch River - Environmental restoration program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected September 8 from Poplar Creek Miles 6.0 and 1.0 was conducted September 13-22, 1994. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments.

  6. Remedial investigation/feasibility study of the Clinch River/Poplar Creek operable unit. Volume 5

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This volume is in support of the findings of an investigation into contamination of the Clinch River and Poplar Creek near the Oak Ridge Reservation (for more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities there). It addresses the quality assurance objectives for measuring the data, presents selected historical data, contains data from several discrete water characterization studies, provides data supporting the sediment characterization, and contains data related to several biota characterization studies.

  7. Anodonta imbecillis QA Test 2, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Atiodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected August 14 from Poplar Creek Miles 6.0 and 4.3 was conducted from August 24-September 2, 1993. Results from this test showed no toxicity (survival effects) to fresh--water mussels during a 9-day exposure to the sediments.

  8. Anodonta imbecillis QA Test 3, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected May 5 from Poplar Creek Miles 6.0 and 2.9 was conducted from May 10-19, 1994. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments.

  9. Effects of hardness and alkalinity in culture and test waters on reproduction of Ceriodaphnia dubia.

    Science.gov (United States)

    Lasier, Peter J; Winger, Parley V; Hardin, Ian R

    2006-10-01

    Ceriodaphnia dubia were cultured in four reconstituted water formulations with hardness and alkalinity concentrations ranging from soft to the moderately hard water that is required by whole-effluent toxicity (WET) testing methods for culturing test organisms. The effects of these culture formulations alone and in combination with two levels of Cl-, SO4(2-), and HCO3- on reproduction of C. dubia were evaluated with the standard three-brood test. Reproduction was significantly reduced when test waters had lower hardness than culture waters. However, reproduction was not significantly different when animals cultured in low-hardness waters were exposed to moderately hard waters. The hardness of the culture water did not significantly affect the sensitivity of C. dubia to the three anions. Conversely, increased hardness in test waters significantly reduced the toxicities of Cl- and SO4(2-), with HCO3- toxicity following the same pattern. Alkalinity exhibited no consistent effect on Cl- and SO4(2-) toxicity. The physiological stress of placing animals cultured in moderately hard water into softer test waters might contribute to marginal failures of otherwise nontoxic effluents. The standard WET protocol should be revised to allow the culture of C. dubia under lower hardness conditions to better represent local surface water chemistries.

  10. Effects of hardness and alkalinity in culture and test waters on reproduction of Ceriodaphnia dubia

    Science.gov (United States)

    Lasier, P.J.; Winger, P.V.; Hardin, I.R.

    2006-01-01

    Ceriodaphnia dubia were cultured in four reconstituted water formulations with hardness and alkalinity concentrations ranging from soft to the moderately hard water that is required by whole-effluent toxicity (WET) testing methods for culturing test organisms. The effects of these culture formulations alone and in combination with two levels of Cl-, SO42, and HCO3- on reproduction of C. dubia were evaluated with the standard three-brood test. Reproduction was significantly reduced when test waters had lower hardness than culture waters. However, reproduction was not significantly different when animals cultured in low-hardness waters were exposed to moderately hard waters. The hardness of the culture water did not significantly affect the sensitivity of C. dubia to the three anions. Conversely, increased hardness in test waters significantly reduced the toxicities of Cl- and SO42-, with HCO3- toxicity following the same pattern. Alkalinity exhibited no consistent effect on Cl- and SO42- toxicity. The physiological stress of placing animals cultured in moderately hard water into softer test waters might contribute to marginal failures of otherwise nontoxic effluents. The standard WET protocol should be revised to allow the culture of C. dubia under lower hardness conditions to better represent local surface water chemistries.

  11. [Studies on biological characteristics and germination conditions of Thladiantha dubia seeds].

    Science.gov (United States)

    Zhao, Chun-Ying; Su, Zhan-Hui; Mao, Xiao-Xia; Tong, Ji-Ming

    2013-07-01

    To study the biological characteristics and find out the optimum condition for germination of seed of Thladiantha dubia Bunge for its standardized culturing. The weight per 1 000 seeds, seed moisture content and seed viability were determined. The biological characteristics were studied and germination conditions of seed of T. dubia were tested under following conditions: different seed soaking time, different temperatures (15, 20, 25, 30, 35 degrees C) and different irradiation time (0, 5, 10, 15, 20 min). The average length, width and thickness of T. Dubia seed were 4.96, 3.25 and 1.08 mm, respectively. The weight per 1 000 seeds was 14.03 g; the seed moisture content was 10.10%; the seed viability was 90.33%. Under the same condition of light, temperature and other factors, the seed germination percentage and germination energy were the highest after seed soaking 24 h. The suitable temperature range of seeds was form 25 degrees C to 35 degrees C. Under different irradiation time, the seed germination percentage and germination energy were the highest after irradiation 10 min. In different germinating beds, the seeds germination percentage and germination energy were the highest on paper (TP), which was 89.33%. The optimum condition for the germination of the seed of T. dubia is seed soaking 12 h, irradiation 10 min, 25-30 degrees C on filter paper.

  12. ORIGEN2 model and results for the Clinch River Breeder Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Croff, A G; Bjerke, M A

    1982-06-01

    Reactor physics calculations and literature information acquisition have led to the development of a Clinch River Breeder Reactor (CRBR) model for the ORIGEN2 computer code. The model is based on cross sections taken directly from physics codes. Details are presented concerning the physical description of the fuel assemblies, the fuel management scheme, irradiation parameters, and initial material compositions. The ORIGEN2 model for the CRBR has been implemented, resulting in the production of graphical and tabular characteristics (radioactivity, thermal power, and toxicity) of CRBR spent fuel, high-level waste, and fuel-assembly structural material waste as a function of decay time. Characteristics for pressurized water reactors (PWRs), commercial liquid-metal fast breeder reactors (LMFBRs), and the Fast Flux Test Facility (FFTF) have also been included in this report for comparison with the CRBR data.

  13. Anodonta imbecillis QA Test 1, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA and CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments to provide a quality assurance mechanism for test organism quality and overall performance of the test. In addition, testing included procedures comparing daily renewal versus non-renewal of test sediments. Testing of sediment samples collected July 15 from Poplar Creek Miles 6.0 and 5.1 was conducted from July 21-30, 1993. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments. Side by side testing of sediments with daily sediment renewal and no sediment renewal showed no differences between methods. This may be due to the absence of toxicity in both samples and may not reflect true differences between the two methods for toxic sediment.

  14. Anodonta imbecillis copper sulfate reference toxicant test, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Toxicity testing of copper sulfate reference toxicant was conducted from May 12-21, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed an LC{sub 50} value of 1.12 mg Cu/L which is lower than the value of 2.02 mg Cu/L obtained in a previous test. Too few tests have been conducted with copper as the toxicant to determine a normal range of values.

  15. Antibacterial activity of Myrciaria dubia (Camu camu) against Streptococcus mutans and Streptococcus sanguinis

    Institute of Scientific and Technical Information of China (English)

    Rosella Camere-Colarossi; Gabriela Ulloa-Urizar; Dyanne Medina-Flores; Stefany Caballero-Garca; Frank Mayta-Tovalino; Juana del Valle-Mendoza

    2016-01-01

    Objective: To evaluate the antibacterial and cytotoxic effect of Myrciaria dubia (Camu camu) (M. dubia) methanol extract, against Streptococcus mutans (ATCC 25175) (S. mutans) and Streptococcus sanguinis (ATCC 10556) (S. sanguinis). Methods: Two methanol extracts of M. dubia were prepared in vitro, from the seeds and pulp. Ten independent tests were prepared for each type of extract, using 0.12% chlor-hexidine solution as positive control. Agar diffusion test was used by preparing wells with the experimental solutions cultivated in anaerobic conditions for 48 h at 37 ° C. Mean-while, the minimum inhibitory concentration and the cytotoxic effect over MDCK cell line was found. Results: A higher antibacterial effect was observed with the methanol seed extract with an inhibitory halo of (21.36 ± 6.35) mm and (19.21 ± 5.18) mm against S. mutans and S. sanguinis, respectively. The methanol extract of the pulp had an effect of (16.20 ± 2.08) mm and (19.34 ± 2.90) mm, respectively. The minimum inhibitory concentration of the pulp extract was 62.5μg/mL for both strains, whereas for the seed antibacterial activity was observed even at low concentrations. The CC50 of the seeds extract was at a higher con-centration than 800μg/mL and 524.37μg/mL for the pulp extract. Conclusions: The experimental findings demonstrated the antibacterial effect of the methanol extract of M. dubia against S. mutans and S. sanguinis. These extracts were not cytotoxic at high concentrations.

  16. Influence of chloride on the chronic toxicity of sodium nitrate to Ceriodaphnia dubia and Hyalella azteca.

    Science.gov (United States)

    Soucek, David J; Dickinson, Amy

    2016-09-01

    While it has been well established that increasing chloride concentration in water reduces the toxicity of nitrite to freshwater species, little work has been done to investigate the effect of chloride on nitrate toxicity. We conducted acute and chronic nitrate (as sodium nitrate) toxicity tests with the cladoceran Ceriodaphnia dubia and the amphipod Hyalella azteca (chronic tests only) over a range of chloride concentrations spanning natural chloride levels found in surface waters representative of watersheds of the Great Lakes Region. Chronic nitrate toxicity test results with both crustaceans were variable, with H. azteca appearing to be one of the more sensitive invertebrate species tested and C. dubia being less sensitive. While the variability in results for H. azteca were to an extent related to chloride concentration in test water that was distinctly not the case for C. dubia. We concluded that the chloride dependent toxicity of nitrate is not universal among freshwater crustaceans. An additional sodium chloride chronic toxicity test with the US Lab strain of H. azteca in the present study suggested that when present as predominantly sodium chloride and with relatively low concentrations of other ions, there is a narrow range of chloride concentrations over which this strain is most fit, and within which toxicity test data are reliable.

  17. Data summary for the near-shore sediment characterization task of the Clinch River Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Levine, D.A.; Hargrove, W.W.; Campbell, K.R.; Wood, M.A.; Rash, C.D.

    1994-10-01

    This report presents the results of the Near-Shore Sediment Characterization Task of the Clinch River Environmental Restoration Program (CR-ERP). The goals of the task were to (1) determine the extent to which near-shore surface sediments are contaminated by releases from the Oak Ridge Reservation (ORR) and (2) provide data for the Watts Bar Reservoir Interagency Permitting Group (WBRIPG) to evaluate the human health risks from exposure to sediments during and following dredging operations. The data collected for this task are also to be used in the Remedial Investigation/Feasibility Study (RLTS) for the CR-ERP operable units (Lower Watts Bar and Clinch River) to characterize the human health risk associated with exposure to near-shore sediments throughout the Watts Bar Reservoir.

  18. Remedial investigation/feasibility study for the Clinch River/Poplar Creek operable unit. Volume 3. Appendix E

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This document contains Appendix E: Toxicity Information and Uncertainty Analysis, description of methods, from the combined Remedial Investigation/Feasibility Study Report for the Clinch River/Poplar Crack (CR/PC) Operable Unit (OU). The CR/PC OU is located in Anderson and Roane Counties, Tennessee and consists of the Clinch River and several of its embayments in Melton Hill and Watts Bar Reservoirs. These waters have received hazardous substances released over a period of 50 years from the US Department of Energy`s Oak Ridge Reservation (ORR), a National Priority List site established under the Comprehensive Environmental Response, Compensation, and Liability Act. A remedial investigation has been conducted to determine the current nature and extent of any contamination and to assess the resulting risk to human health and the environment. The feasibility study evaluates remedial action alternatives to identify any that are feasible for implementation and that would effectively reduce risk. Historical studies had indicated that current problems would likely include {sup 137}Cs in sediment of the Clinch River, mercury in sediment and fish of Poplar Creek and PCBs and pesticides in fish from throughout the OU. Peak releases of mercury and {sup 137}Cs occurred over 35 years ago, and current releases are low. Past releases of PCBs from the ORR are poorly quantified, and current releases are difficult to quantify because levels are so low. The site characterization focused on contaminants in surface water, sediment, and biota. Contaminants in surface water were all found to be below Ambient Water Quality Criteria. Other findings included the following: elevated metals including cesium 137 and mercury in McCoy Branch sediments; PCBs and chlordane elevated in several fish species, presenting the only major human health risk, significant ecological risks in Poplar Creek but not in the Clinch River.

  19. Remedial investigation/feasibility study for the Clinch River/Poplar Creek operable unit. Volume 1. Main text

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This is the combined Remedial Investigation/Feasibility Study Report for the Clinch River/Poplar Crack (CR/PC) Operable Unit (OU). The CR/PC OU is located in Anderson and Roane Counties, Tennessee and consists of the Clinch River and several of its embayments in Melton Hill and Watts Bar Reservoirs. These waters have received hazardous substances released over a period of 50 years from the US Department of Energy`s Oak Ridge Reservation (ORR), a National Priority List site established under the Comprehensive Environmental Response, Compensation, and Liability Act. A remedial investigation has been conducted to determine the current nature and extent of any contamination and to assess the resulting risk to human health and the environment. The feasibility study evaluates remedial action alternatives to identify any that are feasible for implementation and that would effectively reduce risk. Historical studies had indicated that current problems would likely include {sup 137}Cs in sediment of the Clinch River, mercury in sediment and fish of Poplar Creek and PCBs and pesticides in fish from throughout the OU. Peak releases of mercury and {sup 137}Cs occurred over 35 years ago, and current releases are low. Past releases of PCBs from the ORR are poorly quantified, and current releases are difficult to quantify because levels are so low. The site characterization focused on contaminants in surface water, sediment, and biota. Contaminants in surface water were all found to be below Ambient Water Quality Criteria. Other findings included the following: elevated metals including cesium 137 and mercury in McCoy Branch sediments; PCBs and chlordane elevated in several fish species, presenting the only major human health risk, significant ecological risks in Poplar Creek but not in the Clinch River.

  20. Richland's Clinch River pedestrian walkway extension conceptual design : prepared for the Town of Richlands, VA, October, 2013

    OpenAIRE

    Gilboy, Elizabeth Truex; Browning, Lara; Dunn, Matthew; Jessup, Jennifer; Malobicky, Alyssa

    2013-01-01

    Originally established as a planned community whose economy would be supported by mining of rich coal deposits, Richlands was intended to be the Pittsburgh (PA) of the South by the Clinch Valley Coal and Iron Company of Philadelphia. The coming of the Norfolk & Western Railroad supported the capital investment to create a town that would manufacture products such as steel, brick, and glass. It also showcased the deluxe Hotel Richlands and other businesses as well as residential areas. Because...

  1. Remedial investigation/feasibility study for the Clinch River/Poplar Creek operable unit. Volume 4. Appendix F

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This section contains ecotoxicological profiles for the COPECs for the combined Remedial Investigation/Feasibility Study Report for the Clinch River/Poplar Crack (CR/PC) Operable Unit (OU). The ecotoxicological information is presented for only those endpoints for which the chemicals are COPECs. The CR/PC OU is located in Anderson and Roane Counties, Tennessee and consists of the Clinch River and several of its embayments in Melton Hill and Watts Bar Reservoirs. These waters have received hazardous substances released over a period of 50 years from the US Department of Energy`s Oak Ridge Reservation (ORR), a National Priority List site established under the Comprehensive Environmental Response, Compensation, and Liability Act. A remedial investigation has been conducted to determine the current nature and extent of any contamination and to assess the resulting risk to human health and the environment. The feasibility study evaluates remedial action alternatives to identify any that are feasible for implementation and that would effectively reduce risk. Historical studies had indicated that current problems would likely include {sup 137}Cs in sediment of the Clinch River, mercury in sediment and fish of Poplar Creek and PCBs and pesticides in fish from throughout the OU. Peak releases of mercury and {sup 137}Cs occurred over 35 years ago, and current releases are low. Past releases of PCBs from the ORR are poorly quantified, and current releases are difficult to quantify because levels are so low. The site characterization focused on contaminants in surface water, sediment, and biota. Contaminants in surface water were all found to be below Ambient Water Quality Criteria. Other findings included the following: elevated metals including cesium 137 and mercury in McCoy Branch sediments; PCBs and chlordane elevated in several fish species, presenting the only major human health risk, significant ecological risks in Poplar Creek but not in the Clinch River.

  2. FEA of the clinching process of short fiber reinforced thermoplastic with an aluminum sheet using LS-DYNA

    Science.gov (United States)

    Behrens, B.-A.; Bouguecha, A.; Vucetic, M.; Grbic, N.

    2016-10-01

    A structural concept in multi-material design is used in the automotive industry with the aim of achieving significant weight reductions of conventional car bodies. In this respect, the use of aluminum and short fiber reinforced plastics represents an interesting material combination. A wide acceptance of such a material combination requires a suitable joining technique. Among different joining techniques, clinching represents one of the most appealing alternative for automotive applications. This contribution deals with the FE simulation of the clinching process of two representative materials PA6GF30 and EN AW 5754 using the FE software LS-DYNA. With regard to the material modelling of the aluminum sheet, an isotropic material model based on the von Mises plasticity implemented in LS-DYNA was chosen. Analogous to aluminum, the same material model is used for modelling the short fiber reinforced thermoplastic. Additionally, a semi-analytical model for polymers (SAMP-1) also available in LS-DYNA was taken. Finally, the FEA of clinching process is carried out and the comparison of the simulation results is presented above.

  3. The Potential of a Clinch-Lock Polymer Metal Hybrid Technology for Use in Load-Bearing Automotive Components

    Science.gov (United States)

    Grujicic, M.; Sellappan, V.; Arakere, G.; Seyr, Norbert; Obieglo, Andreas; Erdmann, Marc; Holzleitner, Jochen

    2009-10-01

    In order to help meet the needs of automotive original equipment manufacturers and their suppliers for a cost-effective, robust, reliable polymer-metal-hybrid (PMH) technology which can be used for the manufacturing of load-bearing body-in-white (BIW) components and which is compatible with the current BIW manufacturing process chain, a new approach, the so-called direct-adhesion PMH technology, was recently proposed (Grujicic et al., J. Mater. Process. Technol., 2008, 195, p 282-298). Within this approach, the necessary level of polymer-to-metal mechanical interconnectivity is attained through direct adhesion and mechanical interlocking. In the present work, a new concept for mechanical interlocking between the metal and plastics is proposed and analyzed computationally. The approach utilizes some of the ideas used in the spot-clinching joining process and is appropriately named clinch-lock PMH technology. To assess the potential of the clinch-lock approach for providing the required level of metal/polymer mechanical interlocking, a set of finite-element based sheet-metal forming, injection molding and structural mechanics analyses was carried out. The results obtained show that stiffness and buckling resistance levels can be attained which are comparable with those observed in the competing injection overmolding PMH process but with an ~3% lower weight (of the polymer subcomponent) and without the need for holes and for overmolding of the free edges of the metal stamping.

  4. Toxicity and genotoxicity of the quaternary ammonium compound benzalkonium chloride (BAC) using Daphnia magna and Ceriodaphnia dubia as model systems.

    Science.gov (United States)

    Lavorgna, Margherita; Russo, Chiara; D'Abrosca, Brigida; Parrella, Alfredo; Isidori, Marina

    2016-03-01

    The toxicity and genotoxicity of the cationic surfactant benzalkonium chloride (BAC) were studied using Daphnia magna and Ceriodaphnia dubia as model systems. Acute and chronic toxicity testing were performed according to the international standard guidelines and the genotoxicity was detected through the comet assay on cells from whole organisms in vivo exposed. Acute effects occurred at concentrations in the order of tens of μg/L in D. magna and hundreds of μg/L in C. dubia. Chronic effects were found at one order of magnitude less than short-term effects maintaining the same difference in sensitivity between D. magna and C. dubia. BAC induced relevant DNA damage, in both cladocerans; the lowest adverse effect levels were 0.4 and 4 ng/L for D. magna and C. dubia, respectively. As these effective concentrations are far lower than BAC occurrence in surface waters (units of μg/L) a concerning environmental risk cannot be excluded. The findings of this study showed that D. magna and C. dubia, could be used as model organisms to detect acute and chronic toxicity as well as genotoxicity at the whole organism level.

  5. Reprint of "Chronic toxicity of silver nitrate to Ceriodaphnia dubia and Daphnia magna, and potential mitigating factors".

    Science.gov (United States)

    Naddy, Rami B; Gorsuch, Joseph W; Rehner, Anita B; McNerney, Gina R; Bell, Russell A; Kramer, James R

    2007-08-30

    We investigated the chronic toxicity of Ag, as silver nitrate, using two freshwater aquatic cladoceran species, Ceriodaphnia dubia and Daphnia magna, to generate data for the development of a chronic ambient water quality criterion for Ag. Preliminary studies with C. dubia showed variable results which were related to the equilibration time between food and silver. Follow-up testing was conducted using a 3 h equilibration time, which stabilized dissolved Ag concentrations and the toxicity of Ag(+). Results with C. dubia conducted individually (1 per cup, n=10) and in mass (30 per chamber, n=2) gave similar results once similar standardized equilibration times were used. The maximum acceptable toxicant concentration (MATC) of Ag to C. dubia and D. magna was 9.61 and 3.00 microg dissolved Ag/L, respectively. The chronic toxicity of Ag(+) to C. dubia was also evaluated in the presence of: (1) dissolved organic carbon (DOC) and (2) sulfide. The addition of DOC (0.4 mg/L) resulted in a approximately 50% decrease in toxicity while the addition of sulfide (75.4 nM) deceased toxicity by 42%. Whole-body Ag concentration in D. magna was positively correlated with increased levels of Ag exposure, however; we observed a non-statistical decrease in whole-body Na levels, an estimator of sodium homeostasis.

  6. Reproductive aspects of the spider crab Libinia dubia under laboratory conditions Aspectos reproductivos del cangrejo araña Libinia dubia bajo condiciones de laboratorio

    Directory of Open Access Journals (Sweden)

    Claudia Carmona-Osalde

    2012-04-01

    Full Text Available The present study documents some aspects of the reproductive biology of the spider crab Libinia dubia (H. Milne Edwards, 1834 in conditions of captivity. Forty males and 43 ovigerous females were collected with traps and transported to the laboratory, where they were kept in seawater tanks. Average egg count per female was 20,637 (±SD 12,683.33, with an 81% (±SD 4.62 viability until hatching. Males were larger and heavier than females. On average, females measured 69 mm in length × 59 mm in width. The equation for the linear relationship between female weight (W and number of eggs produced per female was: Y = -10,290.03 + 242.89 X (r² = 0.866. Egg development at a temperature of 24 ± 1 °C occurred in five stages based on coloration: stage 1 (day 1-10, bright orange; stage 2 (day 11-24, orange; stage 3 (day 25-29, gray; stage 4 (day 30-34, light gray; and stage 5 (35-37, white, visible larvae. Females spawned at least twice and were receptive to males after each spawning event, although no spermatophore transfer was observed. The adaptive capacity of L. dubia to captivity makes its use feasible in breeding under controlled conditions, suggesting that it has potential for aquaculture.El presente estudio documenta algunos aspectos acerca de la biología reproductiva del cangrejo araña Libinia dubia (H. Milne Edwards, 1834 en condiciones de cautiverio. Cuarenta machos y 43 hembras ovígeras fueron recolectados con trampas y transportados al laboratorio, donde se les mantuvo en estanques de agua marina. El promedio de huevos por hembra fue de 20,637 (±SD 12,683.33, con un 81% (±SD 4.62% de viabilidad hasta el momento de la eclosión. Los machos fueron más grandes y pesados que las hembras. Estas registraron una talla promedio de 69 mm de longitud × 59 mm de ancho. La ecuación para la regresión linear entre el peso de las hembras y el número de huevos producido por hembra fue: Y = -10,290.03 + 242.89 X (r² = 0.866. El desarrollo de los

  7. Synthesis of silver nanoparticles from Melia dubia leaf extract and their in vitro anticancer activity

    Science.gov (United States)

    Kathiravan, V.; Ravi, S.; Ashokkumar, S.

    2014-09-01

    Silver nanoparticles have a significant role in the pharmaceutical science. Especially, silver nanoparticles synthesized by the plant extracts lead a significant role in biological activities such as antimicrobial, antioxidant and anticancer. Keeping this in mind, the present work investigation has been taken up with the synthesized silver nanoparticles using the plant extract of Melia dubia and it characterizes by using UV-visible, XRD and SEM-EDS. The effect of the silver nanoparticles on human breast cancer (KB) cell line has been tested. Silver nanoparticles showed remarkable cytotoxicity activity against KB cell line with evidence of high therapeutic index value are the results are discussed.

  8. Estimated recurrence frequencies for initiating accident categories associated with the Clinch River Breeder Reactor Plant design

    Energy Technology Data Exchange (ETDEWEB)

    Copus, E R

    1982-04-01

    Estimated recurrence frequencies for each of twenty-five generic LMFBR initiating accident categories were quantified using the Clinch River Breeder Reactor Plant (CRBRP) design. These estimates were obtained using simplified systems fault trees and functional event tree models from the Accident Delineation Study Phase I Final Report coupled with order-of-magnitude estimates for the initiator-dependent failure probabilities of the individual CRBRP engineered safety systems. Twelve distinct protected accident categories where SCRAM is assumed to be successful are estimated to occur at a combined rate of 10/sup -3/ times per year while thirteen unprotected accident categories in which SCRAM fails are estimated to occur at a combined rate on the order of 10/sup -5/ times per year. These estimates are thought to be representative despite the fact that human performance factors, maintenance and repair, as well as input common cause uncertainties, were not treated explicitly. The overall results indicate that for the CRBRP design no single accident category appears to be dominant, nor can any be totally eliminated from further investigation in the areas of accident phenomenology for in-core events and post-accident phenomenology for containment.

  9. Influence of container adsorption upon observed pyrethroid toxicity to Ceriodaphnia dubia and Hyalella azteca

    Science.gov (United States)

    Wheelock, Craig E.; Miller, Jeff L.; Miller, Mike J.; Phillips, Bryn M.; Gee, Shirley J.; Tjeerdema, Ronald S.; Hammock, Bruce D.

    2006-01-01

    Pyrethroid insecticides are known for their potential toxicity to aquatic invertebrates and many fish species. A significant problem in the study of pyrethroid toxicity is their extreme hydrophobicity. They can adsorb to test container surfaces and many studies, therefore, report pyrethroid levels as nominal water concentrations. In this study, pyrethroid adsorption to sampling and test containers was measured and several container treatments were examined for their ability to decrease pyrethroid adsorption. None of the chemical treatments were successful at preventing pyrethroid loss from aqueous samples, but vortexing of containers served to resuspend pyrethroids. The effects of the observed adsorption on Ceriodaphnia dubia and Hyalella azteca permethrin toxicity were examined. Species-specific results showed a time-dependent decrease in toxicity following pyrethroid adsorption to test containers for C. dubia, but not for H. azteca. These results demonstrate that pyrethroid adsorption to containers can significantly affect the observed outcome in toxicity-testing and serves as a caution for researchers and testing laboratories. PMID:15951033

  10. Effects of water chemistry on the chronic toxicity of lead to the cladoceran, Ceriodaphnia dubia.

    Science.gov (United States)

    Mager, Edward M; Brix, Kevin V; Gerdes, Robert M; Ryan, Adam C; Grosell, Martin

    2011-03-01

    As the first step toward parameterization of a chronic lead (Pb) biotic ligand model (BLM) for Ceriodaphnia dubia, 7-d toxicity tests were performed in waters modified to evaluate the influences of hardness, DOM (as Suwannee River NOM and Aldrich humic acid (HA)), pH (buffered with 4 mM MOPS) and alkalinity on the chronic toxicity of Pb. Calculated EC(20)s for the control base water test and each of the most extreme modified test waters were as follows in μg L(-1) Pb (95% confidence interval): base water control=45 (14-53), 5 mM CaSO(4)=22 (12-30), 32 mg L(-1) DOM=523 (388-573), 2.5 mM NaHCO(3)=73 (21-120) and pH 6.4 buffered with MOPS=3.9 μg L(-1) Pb (1-5). Results indicate that hardness does not protect against chronic toxicity of Pb to C. dubia, whereas HA does protect at the highest concentration tested (597 μM). Additionally, our findings suggest that low pH increases the chronic toxicity of Pb whereas increased alkalinity is protective. The findings reported herein support the need for a chronic Pb BLM as an alternative approach to hardness-based regulations.

  11. Acute toxicity of runoff from sealcoated pavement to Ceriodaphnia dubia and Pimephales promelas

    Science.gov (United States)

    Mahler, Barbara J.; Ingersoll, Christopher G.; Van Metre, Peter C.; Kunz, James L.; Little, Edward E.

    2015-01-01

    Runoff from coal-tar-based (CT) sealcoated pavement is a source of polycyclic aromatic hydrocarbons (PAHs) and N-heterocycles to surface waters. We investigated acute toxicity of simulated runoff collected from 5 h to 111 days after application of CT sealcoat and from 4 h to 36 days after application of asphalt-based sealcoat containing about 7% CT sealcoat (AS/CT-blend). Ceriodaphnia dubia (cladocerans) and Pimephales promelas (fathead minnows) were exposed in the laboratory to undiluted and 1:10 diluted runoff for 48 h, then transferred to control water and exposed to 4 h of ultraviolet radiation (UVR). Mortality following exposure to undiluted runoff from unsealed asphalt pavement and UVR was ≤10% in all treatments. Test organisms exposed to undiluted CT runoff samples collected during the 3 days (C. dubia) or 36 days (P. promelas) following sealcoat application experienced 100% mortality prior to UVR exposure; with UVR exposure, mortality was 100% for runoff collected across the entire sampling period. Phototoxic-equivalent PAH concentrations and mortality demonstrated an exposure-response relation. The results indicate that runoff remains acutely toxic for weeks to months after CT sealcoat application.

  12. Ultrastructure and Morphology of Compound Eyes of the Scorpionfly Panorpa dubia (Insecta: Mecoptera: Panorpidae.

    Directory of Open Access Journals (Sweden)

    Qing-Xiao Chen

    Full Text Available Mecoptera are unique in holometabolous insects in that their larvae have compound eyes. In the present study the cellular organisation and morphology of the compound eyes of adult individuals of the scorpionfly Panorpa dubia in Mecoptera were investigated by light, scanning electron, and transmission electron microscopy. The results showed that the compound eyes of adult P. dubia are of the apposition type, each eye comprising more than 1200 ommatidia. The ommatidium consists of a cornea, a crystalline cone made up of four cone cells, eight photoreceptors, two primary pigment cells, and 18 secondary pigment cells. The adult ommatidium has a fused rhabdom with eight photoreceptors. Seven photoreceptors extend from the proximal end of the crystalline cone to the basal matrix, whereas the eighth photoreceptor is shorter, extending from the middle level of the photoreceptor cluster to the basal matrix. The fused rhabdom is composed of the rhabdomeres of different photoreceptors at different levels. The adult ommatidia have the same cellular components as the larval ommatidia, but the tiering scheme is different.

  13. 中药赤雹的研究概述%Research Progress in Chinese Medicine Thladiantha Dubia Bunge

    Institute of Scientific and Technical Information of China (English)

    王隶书; 岳乐乐; 程东岩; 王超楠

    2016-01-01

    Thladiantha dubia Bunge is a traditional Chinese medicine in Manzu region applied in the treatment of pain in waist and leg, or strain in lumbar without adverse reaction. By referring to the relative literatures on Thladiantha dubia Bunge from home and abroad, the study progress in the chemical constituents and pharmacological actions of Thladiantha dubia Bunge in the recent 30 years were reviewed to lay foundation for the reasonable exploitation and utilization of Thladiantha dubia Bunge.%赤雹为满族民间习用中药材,治疗腰腿疼痛和腰部扭伤疗效显著,且未见不良反应。本文查阅国内外赤雹研究的相关文献,对其近30年的化学成分和生物活性研究情况进行了综述,为合理开发利用赤雹奠定了基础。

  14. Ceriodaphnia dubia as a potential bio-indicator for assessing acute aluminum oxide nanoparticle toxicity in fresh water environment.

    Directory of Open Access Journals (Sweden)

    Sunandan Pakrashi

    Full Text Available Growing nanomaterials based consumer applications have raised concerns about their potential release into the aquatic ecosystems and the consequent toxicological impacts. So environmental monitoring of the nanomaterials in aqueous systems becomes imperative. The current study reveals the potential of Ceriodaphnia dubia (C. dubia as a bio-indicator for aluminum oxide nanoparticles in a fresh water aquatic ecosystem where it occupies an important ecological niche as a primary consumer. This study aims to investigate the aluminium oxide nanoparticle induced acute toxicity on Ceriodaphnia dubia in a freshwater system. The bioavailability of the aluminum oxide nanoparticles has been studied with respect to their aggregation behavior in the system and correlated with the toxicity endpoints. The oxidative stress generated by the particles contributed greatly toward their toxicity. The crucial role of leached aluminium ion mediated toxicity in the later phases (48 h and 72 h in conjunction with the effects from the nano-sized particles in the initial phases (24 h puts forth the dynamics of nanotoxicity in the test system. The internalization of nanoparticles (both gross and systemic uptake as substantiated through the transmission electron microscopy (TEM and inductively coupled plasma optical emission spectral (ICP-OES analysis was another major contributor toward acute toxicity. Concluding the present study, Ceriodaphnia dubia can be a promising candidate for bio-monitoring the aluminium oxide nanoparticles in a fresh water system.

  15. Ecotoxicological evaluation of water of the hydrographic Basin of the Una River using the bioindicator Ceriodaphnia dubia

    Directory of Open Access Journals (Sweden)

    Tatiane Alves

    2013-12-01

    Full Text Available The majority of the Una River Basin is located in Taubaté County and contributes significantly to its water supply. The main goal of this research was to evaluate the water quality of the Una River using the microcrustacean C. dubia as bioindicator for tests of chronic and acute toxicity. Bimonthly water samples were obtained from each of six localities throughout the Una Basin, from March to October, 2011. Physical-chemical water parameters such as pH, electrical conductivity, hardness, dissolved oxygen and precipitation were measured and correlated to the C. dubia reproductive rates. No significant relationships were found between the water’s electrical conductivity and precipitation with respect to bioindicator reproductive rates. However, at the Sete Voltas, Antas and Rocinha Sub-Basins, significant interactions were detected between some water parameters and reproductive rates, suggesting that water may constrain the reproduction of C. dubia. Acute toxicity was not detected in any of the six sites, while chronic toxicity was recorded at Rocinha, Sete Voltas, Antas, Médio and Baixo Una Sub-Basins. In general, the water quality of the Una Basin, as indicated by the absence of acute toxicity, still remains in an acceptable conservation condition. Caution is needed, however, since slight pollution sources are causing chronic toxicity in some localities. In addition, as the microcrustacean C. dubia, appeared to be a reliable bioindicator in this investigation, we suggest that it be used for continuous water quality monitoring programs.

  16. A survey of the indigenous microbiota (bacteria) in three species of mussels from the Clinch and Holston Rivers, Virginia

    Science.gov (United States)

    Starliper, Clifford E.; Neves, Richard J.; Hanlon, Shane; Whittington, Pamela

    2008-01-01

    Freshwater mussel conservation efforts by many federal and state agencies have increased in recent years. This has led to a greater number of stream surveys, in which mussel die-offs involving high numbers of dead and moribund animals are being observed and reported with greater frequency. Typically, die-offs have been incidentally observed while research was being done for other purposes, therefore, accurate mortality data have been difficult to obtain. Specifically, seasonal die-offs were noted in localized areas of the Clinch and Holston Rivers, Virginia, and to lesser degrees, in neighboring rivers in this geographic region, including southeast Virginia. The observed mussel species affected were primarily the slabside pearlymussel (Lexingtonia dolabelloides) and to lesser extents, the pheasantshell (Actinonaias pectorosa), rainbow mussel (Villosa iris), and the endangered shiny pigtoe (Fusconaia cor). To determine if a bacterial pathogen might be involved in these recurring mussel die-offs, this study examined characteristics of the indigenous microbiota (bacteria) from healthy mussels from sites on the Clinch and Holston Rivers where die-offs were previously observed. These baseline data will allow for recognition of bacterial pathogens in future mussel die-offs. Means for total bacteria from soft tissues ranged from 1.77 × 105 to 3.55 × 106 cfu/g; whereas, the range in means from fluids was 2.92 × 104 to 8.60 × 105 cfu/mL. A diverse microbiota were recovered, including species that are common in freshwater aquatic environments. The most common bacterial groups recovered were motile Aeromonas spp. and nonfermenting bacteria. Flavobacterium columnare, a pathogen to cool- and warm-water fishes was recovered from one specimen, a Villosa iris from the Clinch River.

  17. Influence of water chemistry on the acute toxicity of copper and zinc to the cladoceran Ceriodaphnia cf dubia.

    Science.gov (United States)

    Hyne, Ross V; Pablo, Fleur; Julli, Moreno; Markich, Scott J

    2005-07-01

    This study determined the influence of key water chemistry parameters (pH, alkalinity, dissolved organic carbon [DOC], and hardness) on the aqueous speciation of copper and zinc and its relationship to the acute toxicity of these metals to the cladoceran Ceriodaphnia cf dubia. Immobilization tests were performed for 48-h in synthetic or natural waters buffered at various pH values from 5.5 to 8.4 (other chemical parameters held constant). The toxicity of copper to C. cf dubia decreased fivefold with increasing pH, whereas the toxicity of zinc increased fivefold with increasing pH. The effect of DOC on copper and zinc toxicity to C. cf dubia was determined using natural fulvic acid in the synthetic water. Increasing DOC was found to decrease linearly the toxicity of copper, with the mean effect concentration of copper that immobilized 50% of the cladocerans (EC50) value 45 times higher at 10 mg/L, relative to 0.1 mg/L DOC at pH 6.5. In contrast, the addition of 10 mg/L DOC only resulted in a very small (1.3-fold) reduction in the toxicity of zinc to C. cf dubia. Copper toxicity to C. cf dubia generally did not vary as a function of hardness, whereas zinc toxicity was reduced by a factor of only two, with an increase in water hardness from 44 to 374 mg CaCO3/L. Increasing bicarbonate alkalinity of synthetic waters (30-125 mg/L as CaCO3) decreased the toxicity of copper up to fivefold, which mainly could be attributed to the formation of copper-carbonate complexes, in addition to a pH effect. The toxicity of copper added to a range of natural waters with varying DOC content, pH, and hardness was consistent with the toxicity predicted using the data obtained from the synthetic waters.

  18. QSAR-analysis and mixture toxicity as diagnostic tools: Influence of degradation on the toxicity and mode of action of diuron in algae and daphnids.

    Science.gov (United States)

    Neuwoehner, Judith; Zilberman, Tobias; Fenner, Kathrin; Escher, Beate I

    2010-04-01

    Even though the environmental occurrence of pesticide transformation products is well established, ecotoxicological data for transformation products are often lacking. Therefore, it remains an open question for regulators how to handle transformation products in the process of authorization and risk assessment. Transformation products may (1) possess a similar mode of toxic action as the parent compound, (2) exhibit unexpected effects towards non-target organisms or (3) contribute to overall mixture toxicity through baseline toxicity even if the specific activity of the parent compound is lost. In the present study, a systematic and integrated approach is presented to differentiate between these three options with the goal of identifying transformation products that significantly add to the risk posed by the parent compound. Quantitative structure-activity relationships (QSAR) and a toxic ratio (TR) analysis were used to evaluate the toxicity and mode of toxic action of the transformation products relative to the parent compound. In addition, mixture toxicity experiments were used as diagnostic tools to underpin the mode of action analysis and to elucidate whether the transformation products possess a similar risk potential as the parent compound. As an illustrative example, the phenylurea herbicide diuron was chosen since a sound basis of ecotoxicological data was available not only for diuron itself but also for most of its transformation products. Effects were investigated using the most sensitive species, algae, and the non-target organism Daphnia magna, for which a previous QSAR-analysis of literature data suggested a specific hazard. In the present study the primary transformation products 1-(3,4-dichlorophenyl)-3-methlyurea (DCPMU), 3-(3-chlorophenyl)-1,1-dimethylurea (MCPDMU), and 1-(3,4-dichlorophenyl)urea (DCPU) were identified as specific toxicants in algae, but as baseline toxicants in daphnids. The subsequent loss of the methylurea group during

  19. Remedial investigation/feasibility study of the Clinch River/Poplar Creek operable unit. Volume 1: Main text

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This report presents the findings of an investigation into contamination of the Clinch River and Poplar Creek near the US Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) in eastern Tennessee. For more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities at the ORR. In 1989, the ORR was placed on the National Priorities List (NPL), established and maintained under the federal Comprehensive environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Under CERCLA, NPL sites must be investigated to determine the nature and extent of contamination at the site, assess the risk to human health and the environment posed by the site, and, if necessary, identify feasible remedial alternatives that could be used to clean the site and reduce risk. To facilitate the overall environmental restoration effort at the ORR, CERCLA activities are being implemented individually as distinct operable units (OUs). This document is the combined Remedial Investigation and Feasibility Study Report for the Clinch River/Poplar Creek OU.

  20. Technical management plan for sample generation, analysis, and data review for Phase 2 of the Clinch River Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.C.; Benson, S.B. [Oak Ridge National Lab., TN (United States); Beeler, D.A. [Peer Consultants, Inc., Oak Ridge, TN (United States)] [and others

    1994-03-01

    The Clinch River Remedial Investigation (CRRI) is designed to address the transport, fate, and distribution of waterborne contaminants (radionuclides, metals, and organic compounds) released from the US Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) and to assess potential risks to human health and the environment associated with these contaminants. The remedial investigation is entering Phase 2, which has the following items as its objectives: define the nature and extent of the contamination in areas downstream from the DOE ORR, evaluate the human health and ecological risks posed by these contaminants, and perform preliminary identification and evaluation of potential remediation alternatives. This plan describes the requirements, responsibilities, and roles of personnel during sampling, analysis, and data review for the Clinch River Environmental Restoration Program (CR-ERP). The purpose of the plan is to formalize the process for obtaining analytical services, tracking sampling and analysis documentation, and assessing the overall quality of the CR-ERP data collection program to ensure that it will provide the necessary building blocks for the program decision-making process.

  1. Sphagnum mosses as a microhabitat for invertebrates in acidified lakes and the colour adaptation and substrate preference in Leucorrhinia dubia (Odonata, Anisoptera)

    Energy Technology Data Exchange (ETDEWEB)

    Henrikson, B.-I. (Dept. of Zoology, Sect. of Animal Ecology, Univ. of Goeteborg, Goeteborg (Sweden))

    1993-01-01

    The increase of peat mosses, Sphagnum spp., in acidified lakes leads to a changed microhabitat structure for benthic invertebrates. The importance of this change was investigated for some benthic invertebrates. Comparisons between quantitative samples of Sphagnum and debris within the acidified Lake Stora Haestevatten, in the Lake Gaardsjoen catchment of SW Sweden, showed significantly higher abundances of Chironomidae, Ceratopogonidae, Odonata, Trichoptera, Cladocera and Argyroneta aquatica (Araneae) in Sphagnum. For chironomidae and Cladocera the differences were tenfold. Special reference was made to the libellulid Leucorrhinia dubia which is common in acid lakes. In a laboratory test, late instar larvae of L. dubia were shown to change colour to correspond to the brown and green colour of Sphagnum. This result was completed with a field test where larvae of L. dubia were significantly more common in Sphagnum of the same colour as the larvae. The ability to change colour may have an adaptive value when coexisting with visual predators. Small larvae were more prevalent in Sphagnum and they also showed a preference for this substrate in the laboratory test. Laboratory tests showed mediumsized larvae preferred Sphagnum. Larvae of L. dubia were more successful as predators on Asellus aquaticus in Sphagnum substrate than in debris in the laboratory test. Laboratory predation tests with notonecta glauca, Corixa dentipes, Acilius sulcatus, Hyphydrus ovatus and L. dubia showed that they could all feed on larvae of L. dubia. The complex habitat structure of Sphagnum is probably the reason for the high abundance of invertebrates since it may serve as both shelter against predation and as foraging sites. it is probably important as a key habitat for young instars of, for example, L. dubia. In lakes with large Sphagnum mats, L. dubia can coexist with fish. The expansion of Sphagnum due to acidification will probably benefit many acid-tolerant invertebrate species. (au)

  2. Effects of depleted uranium on the health and survival of Ceriodaphnia dubia and Hyalella azteca

    Science.gov (United States)

    Kuhne, W.W.; Caldwell, C.A.; Gould, W.R.; Fresquez, P.R.; Finger, S.

    2002-01-01

    Depleted uranium (DU) has been used as a substitute for the fissionable enriched uranium component of atomic weapons tested at Los Alamos National Laboratory (LANL) (Los Alamos, NM, USA) since the early 1950s, resulting in considerable concentrations of DU in the soils within the test sites. Although the movement of DU into major aquatic systems has been shown to be minimal, there are many small-order ephemeral streams and areas of standing water in canyons throughout LANL that may be affected by inputs of DU via runoff, erosion, and leaching. Ninety-six-hour acute and 7-d chronic toxicity assays were conducted to measure the toxicity of DU on survival and reproduction of Ceriodaphnia dubia. A 14-d water-only assay was conducted to measure survival and growth of Hyalella azteca. The estimated median lethal concentration (LC50) to produce 50% mortality of the test population for the 96-h Ceriodaphnia dubia assay was 10.50 mg/L. Reproductive effects occurred at a lowest-observable-effect concentration ???3.91 mg/L with a no-observable-effect concentration of 1.97 mg/L. The estimated 14-d LC50 for the Hyalella azteca assay was 1.52 mg/L No significant relationship was detected between growth and DU concentrations. Concentrations at which toxicity effects were observed in this study for both invertebrates exceeded concentrations of total uranium observed in runoff from LANL lands. Thus, it is likely that current runoff levels of uranium do not pose a threat to these types of aquatic invertebrates.

  3. The acute toxicity of major ion salts to Ceriodaphnia dubia: I. ...

    Science.gov (United States)

    The ions Na+, K+, Ca2+, Mg2+, Cl-, SO42-, and HCO3-/CO32- (referred to as “major ions”) are present in all fresh waters and are physiologically required by aquatic organisms, but can be increased to harmful levels by a variety of anthropogenic activities that speed geochemical weathering or otherwise introduce or concentrate ions. While toxicity of these ions to aquatic organisms has been previously shown, it is also known that their toxicity can vary depending on the concentrations of other co-occurring anions, and understanding these relationships is key to predicting toxicity and establishing appropriate environmental limits. In this paper we conduct a series of experiments with Ceriodaphnia dubia to evaluate the acute toxicity of all twelve major ionsalts (pairing one of the cations with one of the anions) and to determine how toxicity of these salts varies as a function of background water chemistry. All salts except CaSO4 and CaCO3 were acutely toxic to C. dubia below saturation, with the lowest LC50s found for K salts. Of the remaining salts, all but CaCl2 showed some degree of decreased toxicity as the ionic content of the background water increased. Experiments that independently varied Ca:Mg ratio, Na:K ratio, Cl:SO4 ratio, and alkalinity/pH were used to show that Ca concentration was the primary factor influencing the toxicities of Na and Mg salts. In contrast, the toxicities of K salts were primarily influenced by the concentration of Na. Th

  4. Blaptica dubia as sentinels for exposure to chemical warfare agents - a pilot study.

    Science.gov (United States)

    Worek, Franz; Seeger, Thomas; Neumaier, Katharina; Wille, Timo; Thiermann, Horst

    2016-11-16

    The increased interest of terrorist groups in toxic chemicals and chemical warfare agents presents a continuing threat to our societies. Early warning and detection is a key component for effective countermeasures against such deadly agents. Presently available and near term solutions have a number of major drawbacks, e.g. lack of automated, remote warning and detection of primarily low volatile chemical warfare agents. An alternative approach is the use of animals as sentinels for exposure to toxic chemicals. To overcome disadvantages of vertebrates the present pilot study was initiated to investigate the suitability of South American cockroaches (Blaptica dubia) as warning system for exposure to chemical warfare nerve and blister agents. Initial in vitro experiments with nerve agents showed an increasing inhibitory potency in the order tabun - cyclosarin - sarin - soman - VX of cockroach cholinesterase. Exposure of cockroaches to chemical warfare agents resulted in clearly visible and reproducible reactions, the onset being dependent on the agent and dose. With nerve agents the onset was related to the volatility of the agents. The blister agent lewisite induced signs largely comparable to those of nerve agents while sulfur mustard exposed animals exhibited a different sequence of events. In conclusion, this first pilot study indicates that Blaptica dubia could serve as a warning system to exposure of chemical warfare agents. A cockroach-based system will not detect or identify a particular chemical warfare agent but could trigger further actions, e.g. specific detection and increased protective status. By designing appropriate boxes with (IR) motion sensors and remote control (IR) camera automated off-site warning systems could be realized.

  5. Seed dormancy and germination in Jeffersonia dubia (Berberidaceae) as affected by temperature and gibberellic acid.

    Science.gov (United States)

    Rhie, Y H; Lee, S Y; Kim, K S

    2015-03-01

    The genus Jeffersonia, which contains only two species, has a trans-Atlantic disjunct distribution. The aims of this study were to determine the requirements for breaking dormancy and germination of J. dubia seeds and to compare its dormancy characteristics with those of the congener in eastern North America. Ripe seeds of J. dubia contain an underdeveloped embryo and were permeable to water. In nature, seeds were dispersed in May, while embryos began to grow in September, and were fully elongated by late November. Germination started in March of the next year, and seeds emerged as seedlings soon after germination. In laboratory experiments, incubation at high temperatures (25 °C, 25/15 °C) for at least 8 weeks was required to initiate embryo growth, while a transfer to moderate temperatures (20/10 °C, 15/6 °C) was needed for the completion of embryo growth. At least 8 weeks at 5 °C was effective in overcoming physiological dormancy and for germination in seeds after the embryos had fully elongated. Thus, both high and low temperatures were essential to break dormancy. Gibberellic acid (GA3 ) treatment could substitute for the high temperature requirement, but not for the low temperature requirement. Based on the dormancy-breaking requirements, it is confirmed that the seeds have deep simple morphophysiological dormancy. This dormancy type is similar to that of seeds of the eastern North American species J. diphylla. Although seeds require 10-11 months from seed dispersal to germination in nature, under controlled conditions they required only 3 months after treatment with 1000 mg·l(-1) GA3 , followed by incubation at 15/6 °C. This represents practical knowledge for propagation of these plants from seed.

  6. Preliminary phytochemical and antimicrobial investigations on Melia Dubia Bark: Department of Pharmaceutical Chemistry, J.S.S. College of Pharmacy, Rocklands, P.B. No.20, Ootacamund - 643 001, Tamilnadu, India.

    Science.gov (United States)

    1999-07-01

    The various parts of Melia dubia (Meliaceae) plant was observed to be used by the local tribes of Nilgiris for various infections. There was no report on antimicrobial activity of Melia dubia. Therefore, a preliminary phytochemical analysis and antimicrobial investigations were carried out on different extracts of Melia dubia bark. Ethanolic and aqueous extracts of the bark were found to posses significant antibacterial activity against Staphylococcus aureus.

  7. Effects of Temperature, Salinity, pH, and Light on Filtering and Grazing Rates of a Calanoid Copepod (Schmackeria dubia

    Directory of Open Access Journals (Sweden)

    Changling Li

    2008-01-01

    Full Text Available Calanoid copepods are key components of the marine food web and the food sources of many larval fishes and planktivores, and grazers of phytoplankton. Understanding the ranges of major environmental variables suitable for their growth is essential to maintain the balance between trophic links and resources protection. In this study, the effects of temperature, salinity, pH, and light intensity on the filtering and grazing rates of a herbivorous copepod (Schmackeria dubia were conducted in several control experiments. Our results indicated that experimental animals grazed normally at water temperatures between 15 and 35°C. The filtering and grazing rates increased by onefold at water temperatures from 15 to 25°C, with a peak at around 30°C. S. dubia fed normally at salinity ranging from 20 to 30 ppt, with significantly low filtering and grazing rates at salinity below 15 ppt and above 35 ppt. The filtering and grazing rates increased as pH increased, peaked at approximately 8.5, and then decreased substantially. Light intensity also displayed an important impact on the filtering and grazing rates. Filtering and grazing rates were high when light intensity was greater than 20 and less than 200 µmol m-2 s-1. S. dubia nearly stopped feeding at low light intensity (less than 20 µmol m-2 s-1.

  8. Phase 1 data summary report for the Clinch River Remedial Investigation: Health risk and ecological risk screening assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cook, R.B.; Adams, S.M.; Beauchamp, J.J.; Bevelhimer, M.S.; Blaylock, B.G.; Brandt, C.C.; Ford, C.J.; Frank, M.L.; Gentry, M.J.; Holladay, S.K.; Hook, L.A.; Levine, D.A.; Longman, R.C.; McGinn, C.W.; Skiles, J.L.; Suter, G.W.; Williams, L.F.

    1992-12-01

    The Clinch River Remedial Investigation (CRRI) is designed to address the transport, fate, and distribution of waterborne contaminants released from the US Department of Energy's (DOE's) Oak Ridge Reservation (ORR) and to assess potential risks to human health and the environment associated with these contaminants. The contaminants released since the early 1940s include a variety of radionuclides, metals, and organic compounds. The purpose of this report is to summarize the results of Phase 1 of the CRRI. Phase 1 was designed to (1) obtain high-quality data to confirm existing historical data for contaminant levels in fish, sediment, and water from the CR/WBR; (2) determine the in the range of contaminant concentrations present river-reservoir system; (3) identify specific contaminants of concern; and (4) establish the reference (background) concentrations for those contaminants.

  9. Markovian reliability analysis under uncertainty with an application on the shutdown system of the Clinch River Breeder Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Papazoglou, I A; Gyftopoulos, E P

    1978-09-01

    A methodology for the assessment of the uncertainties about the reliability of nuclear reactor systems described by Markov models is developed, and the uncertainties about the probability of loss of coolable core geometry (LCG) of the Clinch River Breeder Reactor (CRBR) due to shutdown system failures, are assessed. Uncertainties are expressed by assuming the failure rates, the repair rates and all other input variables of reliability analysis as random variables, distributed according to known probability density functions (pdf). The pdf of the reliability is then calculated by the moment matching technique. Two methods have been employed for the determination of the moments of the reliability: the Monte Carlo simulation; and the Taylor-series expansion. These methods are adopted to Markovian problems and compared for accuracy and efficiency.

  10. Uptake and fate of phenol and aniline in rainbow trout and daphnids during single-compound and complex-mixture exposures

    Energy Technology Data Exchange (ETDEWEB)

    Dauble, D.D.; Riley, R.G.; Bean, R.M.; Lusty, E.W.; Hanf, R.W. Jr.

    1984-10-01

    Studies were conducted of the potential for uptake and mobilization of phenol and aniline when presented as single compounds to the biouptake of these compounds within a complex water-soluble fraction (WSF) of a coal liquid. Estimated bioconcentration factors (BCF) of phenol-only exposures differed from BCFs obtained in the presence of the WSF. Differences in uptake could be due to competitive interactions among similar molecules for uptake and absorption, since phenolic compounds comprised nearly 90% of the soluble components in the complex mixture. Observed differences in unextractable /sup 14/C residues suggested selective binding of phenol or metabolites to trout tissue storage sites. Differences in potential for bioaccumulation of phenol in complex mixtures were not consistent with estimates of BCF as determined by measured octanol/water coefficient values. In contrast to phenol, presence of coal-liquid water solubles did not significantly influence either the uptake or elimination of /sup 14/C aniline by daphnids or trout. Identification of metabolites would provide useful information on potential differences in biotransformation and elimination mechanisms in complex organic mixtures. 15 references, 2 figures, 6 tables.

  11. Second report on the Oak Ridge National Laboratory Biological Monitoring and Abatement Program for White Oak Creek Watershed and the Clinch River

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M. [ed.; Adams, S.M.; Bailey, R.D.; Blaylock, B.G.; Boston, H.L.; Cox, D.K.; Huston, M.A.; Kimmel, B.L.; Loar, J.M.; Olsen, C.R.; Ryon, M.G.; Shugart, L.R.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.; Walton, B.T.; Talmage, S.S.; Murphy, J.B.; Valentine, C.K. [Oak Ridge National Lab., TN (United States); Appellanis, S.M.; Jimenez, B.D. [Puerto Rico Univ., San Juan (Puerto Rico); Huq, M.V. [Connecticut Dept. of Environmental Protection, Hamden, CT (United States); Meyers-Schone, L.J. [Frankfurter, Gross-Gerau (Germany); Mohrbacher, D.A. [Automated Sciences Group, Inc., Oak Ridge, TN (United States); Olsen, C.R. [USDOE Office of Energy Research, Washington, DC (United States). Environmental Sciences Div.; Stout, J.G. [Cincinnati Univ., OH (United States)

    1992-12-01

    As a condition of the National Pollutant Discharge Elimination System (NPDES) permit issued to Oak Ridge National Laboratory (ORNL) on April 1, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for White Oak Creek (WOC); selected tributaries of WOC, including Fifth Creek, First Creek, Melton Branch, and Northwest Tributary; and the Clinch River. BMAP consists of seven major tasks that address both radiological and nonradiological contaminants in the aquatic and terrestrial environs on-site and the aquatic environs off-site. These tasks are (1) toxicity monitoring; (2) bioaccumulation monitoring of nonradiological contaminants in aquatic biota; (3) biological indicator studies; (4) instream ecological monitoring; (5) assessment of contaminants in the terrestrial environment; (6) radioecology of WOC and White Oak Lake (WOL); and (7) contaminant transport, distribution, and fate in the WOC embayment-Clinch River-Watts Bar Reservoir system. This document, the second of a series of annual reports, described the results of BMAP studies conducted in 1987.

  12. Effects of water quality parameters on boron toxicity to Ceriodaphnia dubia.

    Science.gov (United States)

    Dethloff, Gail M; Stubblefield, William A; Schlekat, Christian E

    2009-07-01

    The potential modifying effects of certain water quality parameters (e.g., hardness, alkalinity, pH) on the acute toxicity of boron were tested using a freshwater cladoceran, Ceriodaphnia dubia. By comparison, boron acute toxicity was less affected by water quality characteristics than some metals (e.g., copper and silver). Increases in alkalinity over the range tested did not alter toxicity. Increases in water hardness appeared to have an effect with very hard waters (>500 mg/L as CaCO(3)). Decreased pH had a limited influence on boron acute toxicity in laboratory waters. Increasing chloride concentration did not provide a protective effect. Boron acute toxicity was unaffected by sodium concentrations. Median acute lethal concentrations (LC(50)) in natural water samples collected from three field sites were all greater than in reconstituted laboratory waters that matched natural waters in all respects except for dissolved organic carbon. Water effect ratios in these waters ranged from 1.4 to 1.8. In subsequent studies using a commercially available source of natural organic matter, acute toxicity decreased with increased dissolved organic carbon, suggesting, along with the natural water studies, that dissolved organic carbon should be considered further as a modifier of boron toxicity in natural waters where it exceeds 2 mg/L.

  13. Remedial investigation/feasibility study for the Clinch River/Poplar Creek operable unit. Volume 2. Appendixes A, B, C, D

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This document contains appendices A (water characterization), B (sediment characterization), C (biota Characterization), D (applicable or relevant and appropriate requirements) from the combined Remedial Investigation/Feasibility Study Report for the Clinch River/Poplar Crack (CR/PC) Operable Unit (OU). The CR/PC OU is located in Anderson and Roane Counties, Tennessee and consists of the Clinch River and several of its embayments in Melton Hill and Watts Bar Reservoirs. These waters have received hazardous substances released over a period of 50 years from the US Department of Energy`s Oak Ridge Reservation (ORR), a National Priority List site established under the Comprehensive Environmental Response, Compensation, and Liability Act. A remedial investigation has been conducted to determine the current nature and extent of any contamination and to assess the resulting risk to human health and the environment. The feasibility study evaluates remedial action alternatives to identify any that are feasible for implementation and that would effectively reduce risk. Historical studies had indicated that current problems would likely include {sup 137}Cs in sediment of the Clinch River, mercury in sediment and fish of Poplar Creek and PCBs and pesticides in fish from throughout the OU. Peak releases of mercury and {sup 137}Cs occurred over 35 years ago, and current releases are low. Past releases of PCBs from the ORR are poorly quantified, and current releases are difficult to quantify because levels are so low. The site characterization focused on contaminants in surface water, sediment, and biota. Contaminants in surface water were all found to be below Ambient Water Quality Criteria. Other findings included the following: elevated metals including cesium 137 and mercury in McCoy Branch sediments; PCBs and chlordane elevated in several fish species, presenting the only major human health risk, significant ecological risks in Poplar Creek but not in the Clinch River.

  14. Third report on the Oak Ridge National Laboratory Biological Monitoring and Abatement Program for White Oak Creek Watershed and the Clinch River

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M. [ed.; Adams, S.M.; Bailey, R.D. [and others

    1994-03-01

    As a condition of the National Pollutant Discharge Elimination System (NPDES) permit issued to Oak Ridge National Laboratory (ORNL) on April 1, 1985, a Biological Monitoring and Abatement Program (BMAP) was developed for White Oak Creek (WOC); selected tributaries of WOC, including Fifth Creek, First Creek, Melton Branch, and Northwest Tributary; and the Clinch River. The BMAP currently consists of six major tasks that address both radiological and nonradiological contaminants in the aquatic and terrestrial environs at ORNL. These are (1) toxicity monitoring, (2) bioaccumulation monitoring of nonradiological contaminants in aquatic biota, (3) biological indicator studies, (4) instream ecological monitoring, (5) assessment of contaminants in the terrestrial environment, and (6) radioecology of WOC and White Oak Lake (WOL). The investigation of contaminant transport, distribution, and fate in the WOC embayment-Clinch River-Watts Bar Reservoir system was originally a task of the BMAP but, in 1988, was incorporated into the Resource Conservation and Recovery Act Facility Investigation for the Clinch River, a separate study to assess offsite contamination from all three Department of Energy facilities in Oak Ridge.

  15. Toxicity of noradrenaline, a novel anti-biofouling component, to two non-target zooplankton species, Daphnia magna and Ceriodaphnia dubia.

    Science.gov (United States)

    Overturf, C L; Wormington, A M; Blythe, K N; Gohad, N V; Mount, A S; Roberts, A P

    2015-05-01

    Noradrenaline (NA) is the active component of novel antifouling agents and acts by preventing attachment of fouling organisms. The goal of this study was to examine the toxicity of NA to the non-target zooplankton D. magna and C. dubia. Neonates were exposed to one of five concentrations of NA and effects on survival, reproduction and molting were determined. Calculated LC50 values were determined to be 46 and 38 μM in C. dubia and D. magna, respectively. A 10-day C. dubia study found that reproduction metrics were significantly impacted at non-lethal concentrations. In D. magna, concentrations greater than 40 μM significantly impacted molting. A toxicity test was conducted with D. magna using oxidized NA, which yielded similar results. These data indicate that both NA and oxidized NA are toxic to non-target zooplankton. Results obtained from this study can be used to guide future ecological risk assessments of catecholamine-based antifouling agents.

  16. CLONACIÓN Y FILOGENIA MOLECULAR DE UN SEGMENTO DEL GEN CODANTE DE LA ACTINA DE MYRCIARIA DUBIA “CAMU-CAMU”: UN CANDIDATO PARA GEN DE REFERENCIA

    Directory of Open Access Journals (Sweden)

    Juan Carlos Castro Gómez

    2012-12-01

    Full Text Available Myrciaria dubia “camu-camu” es un frutal amazónico caracterizado por su amplia variación de vitamina C. Pero los estudios genético moleculares que puedan explicar esta variación son limitados. Por ello nuestro objetivo fue realizar la clonación y filogenia molecular de un segmento del gen codante de la actina de M. dubia. Las muestras fueron obtenidas de la colección de germoplasma del INIA. Luego, el ARN fue purificado y mediante RT-PCR con cebadores degenerados se amplificó un segmento del gen. En base a la secuencia obtenida se diseñaron cebadores específicos para PCR en tiempo real. Los resultados muestran que se ha aislado, clonado y secuenciado un segmento del gen codante de actina de M. dubia y detectado su expresión en hojas, pulpa y cáscara de M. dubia. Así, con el soporte de herramientas bioinformáticas y uso de técnicas de biología molecular hemos aislado, clonado y secuenciado un segmento del gen codante de la actina de M. dubia. Asimismo, los análisis realizados muestran que el gen se expresa y presenta niveles similares de expresión en hojas, pulpa y cáscara de M. dubia. Sin embargo, es necesario realizar más experimentos a fin de verificar su estabilidad de expresión.

  17. CLONACIÓN Y FILOGENIA MOLECULAR DE UN SEGMENTO DEL GEN CODANTE DE LA ACTINA DE MYRCIARIA DUBIA “CAMU-CAMU”: UN CANDIDATO PARA GEN DE REFERENCIA

    Directory of Open Access Journals (Sweden)

    Juan Castro Gómez

    2012-12-01

    Full Text Available Myrciaria dubia “camu-camu” es un frutal amazónico caracterizado por su amplia variación de vitamina C. Pero los estudios genético moleculares que puedan explicar esta variación son limitados. Por ello nuestro objetivo fue realizar la clonación y filogenia molecular de un segmento del gen codante de la actina de M. dubia. Las muestras fueron obtenidas de la colección de germoplasma del INIA. Luego, el ARN fue purificado y mediante RT-PCR con cebadores degenerados se amplificó un segmento del gen. En base a la secuencia obtenida se diseñaron cebadores específicos para PCR en tiempo real. Los resultados muestran que se ha aislado, clonado y secuenciado un segmento del gen codante de actina de M. dubia y detectado su expresión en hojas, pulpa y cáscara de M. dubia. Así, con el soporte de herramientas bioinformáticas y uso de técnicas de biología molecular hemos aislado, clonado y secuenciado un segmento del gen codante de la actina de M. dubia. Asimismo, los análisis realizados muestran que el gen se expresa y presenta niveles similares de expresión en hojas, pulpa y cáscara de M. dubia. Sin embargo, es necesario realizar más experimentos a fin de verificar su estabilidad de expresión.

  18. AISLAMIENTO DE ADN GENÓMICO DE Myrciaria dubia (HBK “CAMU CAMU” APROPIADO PARA ANÁLISIS MOLECULARES

    Directory of Open Access Journals (Sweden)

    Juan Carlos Castro Gómez

    2012-06-01

    Full Text Available Myrciaria dubia “camu-camu”, una especie nativa de la Amazonía que produce frutos con alto contenido de vitamina C y otras sustancias importantes. Sin embargo, los estudios moleculares de esta planta son escasos, por falta de un protocolo reproducible para purificar sus ácidos nucléicos. El objetivo de este trabajo fue establecer un protocolo para aislar el ADN genómico a partir de hojas de M. dubia, apropiado para análisis moleculares. El ADN se purificó con un protocolo modificado, la calidad y cantidad se estimó por espectrofotometría y electroforesis en gel de agarosa. Adicionalmente, la calidad se evaluó mediante RAPD. El ratio de calidad (A260/A280 promedio del ADN fue 1.9±0.1 y el espectro de absorción UV/Vis presentó un único pico de máxima absorbancia a 260nm. Mediante electroforesis el ADN fue íntegro y sin ARN. También, la síntesis de amplicones RAPD nos sugiere ausencia de inhibidores para polimerasas. La concentración promedio del ADN fue 99±33 ng/ml y el rendimiento promedio fue 237±80 mg ADN/g hoja. En conclusión, se ha establecido un protocolo de aislamiento de ADN genómico a partir de hojas de Myrciaria dubia “camu camu”, caracterizado por permitirnos obtener ADN de alta calidad y cantidad suficiente para análisis moleculares como el RAPD.

  19. Congo red dye affects survival and reproduction in the cladoceran Ceriodaphnia dubia. Effects of direct and dietary exposure.

    Science.gov (United States)

    Hernández-Zamora, Miriam; Martínez-Jerónimo, Fernando; Cristiani-Urbina, Eliseo; Cañizares-Villanueva, Rosa Olivia

    2016-12-01

    Nearly 7 00000 tons of dyes are produced annually throughout the world. Azo dyes are widely used in the textile and paper industries due to their low cost and ease of application. Their extensive use results in large volumes of wastewater being discharged into aquatic ecosystems. Large volume discharges constitute a health risk since many of these dyes, such as Congo Red, are elaborated with benzidine, a known carcinogenic compound. Information regarding dye toxicity in aquatic ecosystems is limited. Therefore, the aim of the present study was to evaluate the effect of Congo Red on survival and reproduction of Ceriodaphnia dubia. We determined the 48 h median lethal concentration (LC50) and evaluated the effects of sublethal concentrations in subchronic exposures by using as food either fresh algae or algae previously exposed to the dye. LC50 was 13.58 mg L(-1). In subchronic assays, survival was reduced to 80 and 55 %, and fertility to 40 and 70 %, as compared to the control, in C. dubia fed with intoxicated cells or with the mix of intoxicated + fresh algae, respectively, so the quantity and type of food had a significant effect. We determined that Congo Red is highly toxic to C. dubia since it inhibits survival and fertility in concentrations exceeding 3 mg L(-1). Our results show that this dye produces negative effects at very low concentrations. Furthermore, our findings warn of the risk associated with discharging dyes into aquatic environments. Lastly, the results emphasize the need to regulate the discharge of effluents containing azo dyes.

  20. Thiocyanate, calcium and sulfate as causes of toxicity to Ceriodaphnia dubia in a hard rock mining effluent.

    Science.gov (United States)

    Brix, Kevin V; Gerdes, Robert; Grosell, Martin

    2010-10-01

    A series of Toxicity Identification Evaluations (TIEs) to identify the cause(s) of observed toxicity to Ceriodaphnia dubia have been conducted on a hard rock mining effluent. Characteristic of hard rock mining discharges, the effluent has elevated (∼3000 mg l(-1)) total dissolved solids (TDS) composed primarily of Ca(2+) and SO(4)(2-). The effluent typically exhibits 6-12 toxic units (TUs) when tested with C. dubia. Phase I and II toxicity identification evaluations (TIEs) indicated Ca(2+) and SO(4)(2-) contributed only ∼4 TUs of toxicity, but this was likely an underestimate due to problems with simulating the supersaturated CaSO(4) concentrations in the effluent. Treatment of the effluent with BaCO(3) to precipitate Ca(2+) and SO(4)(2-) revealed that these ions contribute ∼6 TUs of the observed toxicity, but the remaining source(s) of toxicity (up to 6 TUs) remained unidentified. Subsequent investigations identified thiocyanate (SCN(-)) in the effluent at 100-150 μM. Toxicity tests reveal that C. dubia are sensitive to SCN(-) with an estimated IC25 of 8.3 μΜ for reproduction in moderately hard water suggesting between 12 and 18 TUs of toxicity in the effluent. Additional experiments demonstrated that SCN(-) toxicity is reduced in the high TDS matrix of the mining effluent. Testing of a mock effluent simulating the major ion and SCN(-) concentrations resulted in 10.4 TUs, suggesting that Ca(2+), SO(4)(2-) and SCN(-) are the three toxicants present in this effluent. This research suggests SCN(-) may be a more common cause of toxicity in mining effluents than is generally recognized.

  1. Fractionation of fulvic acid by iron and aluminum oxides: influence on copper toxicity to Ceriodaphnia dubia

    Science.gov (United States)

    Smith, Kathleen S.; James F. Ranville,; Emily K. Lesher,; Daniel J. Diedrich,; Diane M. McKnight,; Ruth M. Sofield,

    2014-01-01

    This study examines the effect on aquatic copper toxicity of the chemical fractionation of fulvic acid (FA) that results from its association with iron and aluminum oxyhydroxide precipitates. Fractionated and unfractionated FAs obtained from streamwater and suspended sediment were utilized in acute Cu toxicity tests on ,i>Ceriodaphnia dubia. Toxicity test results with equal FA concentrations (6 mg FA/L) show that the fractionated dissolved FA was 3 times less effective at reducing Cu toxicity (EC50 13 ± 0.6 μg Cu/L) than were the unfractionated dissolved FAs (EC50 39 ± 0.4 and 41 ± 1.2 μg Cu/L). The fractionation is a consequence of preferential sorption of molecules having strong metal-binding (more aromatic) moieties to precipitating Fe- and Al-rich oxyhydroxides, causing the remaining dissolved FA to be depleted in these functional groups. As a result, there is more bioavailable dissolved Cu in the water and hence greater potential for Cu toxicity to aquatic organisms. In predicting Cu toxicity, biotic ligand models (BLMs) take into account dissolved organic carbon (DOC) concentration; however, unless DOC characteristics are accounted for, model predictions can underestimate acute Cu toxicity for water containing fractionated dissolved FA. This may have implications for water-quality criteria in systems containing Fe- and Al-rich sediment, and in mined and mineralized areas in particular. Optical measurements, such as specific ultraviolet absorbance at 254 nm (SUVA254), show promise for use as spectral indicators of DOC chemical fractionation and inferred increased Cu toxicity.

  2. Individual and binary toxicity of anatase and rutile nanoparticles towards Ceriodaphnia dubia.

    Science.gov (United States)

    Iswarya, V; Bhuvaneshwari, M; Chandrasekaran, N; Mukherjee, Amitava

    2016-09-01

    Increasing usage of engineered nanoparticles, especially Titanium dioxide (TiO2) in various commercial products has necessitated their toxicity evaluation and risk assessment, especially in the aquatic ecosystem. In the present study, a comprehensive toxicity assessment of anatase and rutile NPs (individual as well as a binary mixture) has been carried out in a freshwater matrix on Ceriodaphnia dubia under different irradiation conditions viz., visible and UV-A. Anatase and rutile NPs produced an LC50 of about 37.04 and 48mg/L, respectively, under visible irradiation. However, lesser LC50 values of about 22.56 (anatase) and 23.76 (rutile) mg/L were noted under UV-A irradiation. A toxic unit (TU) approach was followed to determine the concentrations of binary mixtures of anatase and rutile. The binary mixture resulted in an antagonistic and additive effect under visible and UV-A irradiation, respectively. Among the two different modeling approaches used in the study, Marking-Dawson model was noted to be a more appropriate model than Abbott model for the toxicity evaluation of binary mixtures. The agglomeration of NPs played a significant role in the induction of antagonistic and additive effects by the mixture based on the irradiation applied. TEM and zeta potential analysis confirmed the surface interactions between anatase and rutile NPs in the mixture. Maximum uptake was noticed at 0.25 total TU of the binary mixture under visible irradiation and 1 TU of anatase NPs for UV-A irradiation. Individual NPs showed highest uptake under UV-A than visible irradiation. In contrast, binary mixture showed a difference in the uptake pattern based on the type of irradiation exposed.

  3. Esfenvalerate toxicity to the cladoceran Ceriodaphnia dubia in the presence of green algae, Pseudokirchneriella subcapitata.

    Science.gov (United States)

    Brander, Susanne M; Mosser, Christopher M; Geist, Juergen; Hladik, Michelle L; Werner, Inge

    2012-11-01

    The presence of phytoplankton, like other particulate organic matter, can interfere with the effects of hydrophobic contaminants such as pyrethroid pesticides. However, the reduction or elimination of toxicity by algae added as food during testing is not taken into account in standard US EPA whole effluent toxicity (WET) zooplankton tests. On the other hand, WET test conditions may overestimate toxicity of such compounds in highly productive surface waters with high concentrations of detritus and other particulate matter. In addition, WET tests do not measure impaired swimming ability or predator avoidance behavior as an indicator of increased mortality risk. This study used a modified version of the US EPA WET Ceriodaphnia dubia acute test to investigate the effects of phytoplankton on toxicity of the pyrethroid insecticide, esfenvalerate. Animals were exposed simultaneously to different concentrations of esfenvalerate and green algae (Pseudokirchneriella subcapitata). Mortality and predation risk were recorded after 4 and 24 h. Algae at or below concentrations specified in the WET protocol significantly reduced mortality. Regardless, organisms exposed to esfenvalerate were unable to avoid simulated predation in the presence of algae at any concentration. After 12 h, esfenvalerate adsorbed to algae represented 68-99 % of the total amount recovered. The proportion of algae-bound insecticide increased with algal concentration indicating that conclusions drawn from toxicity tests in which algae are added as food must be interpreted with caution as the dissolved fraction of such hydrophobic contaminants is reduced. Additionally, our results strongly suggest that the EPA should consider adding ecologically-relevant endpoints such as swimming behavior to standard WET protocols.

  4. Toxic effects of Pseudanabaena tenuis (Cyanobacteria on the cladocerans Daphnia magna and Ceriodaphnia dubia Efectos tóxicos de Pseudanabaena tenuis (Cyanobacteria en los cladóceros Daphnia magna y Ceriodaphnia dubia

    Directory of Open Access Journals (Sweden)

    Roxana Olvera-Ramírez

    2010-01-01

    Full Text Available Some cyanobacteria can produce toxins that affect the aquatic biota and represent a human health risk. The cyanobacterium Pseudanabaena tenuis was isolated from the Valle de Bravo dam, and cultured in the laboratory under controlled conditions. We determined the acute toxic effects and performed a chronic (consumption test in the cladocerans Daphnia magna (a reference test organism and Ceriodaphnia dubia (a cosmopolitan species. To determine acute toxicity, three exposure ways were assayed: a cell-free culture medium, b crude cell extracts of the cyanobacterium after lysing, and c aqueous extracts of P. tenuis phycobiliproteins. On the other hand, both cladocerans were fed P. tenuis, assessing the effects on survival and reproduction. For comparison, a control culture of both cladocerans was fed the green microalga Pseudokirchneriella subcapitata. Exposure to the cell-free culture medium did not produce any mortality in either cladoceran, but the aqueous and crude extracts generated acute toxicity. D. magna and C. dubia were negatively affected when fed P. tenuis, since their survival, total progeny, average number of neonates per clutch, and the number of clutches decreased. C. dubia was more sensitive than D. magna, both in the acute toxicity tests and to the effects of P. tenuis consumption. Although most of the blooms around the world are dominated by cyanobacteria of the genus Microcystis, attention should be given to other species, such as P. tenuis, because, frequently, it is not recognized that smaller cyanobacteria could exceed the larger species in terms of biomass, and produce noxious biological effects.Algunas cianobacterias producen toxinas que afectan la biota acuática y representan un riesgo para la salud humana. La cianobacteria Pseudanabaena tenuis fue aislada del embalse Valle de Bravo y cultivada en el laboratorio. Se determinaron los efectos tóxicos agudos (por exposición y se evaluó la toxicidad crónica (por consumo

  5. Oak Ridge National Laboratory Biological Monitoring and Abatement Program for White Oak Creek Watershed and the Clinch River

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M.; Adams, S.M.; Allison, L.J.; Blaylock, B.G.; Boston, H.L.; Huston, M.A.; Kimmel, B.L.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.; Walton, B.T.; Kitchings, J.T.; Olsen, C.R.

    1991-09-01

    On April 1, 1986, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge National Laboratory (ORNL) (EPA 1986). As specified in Part 3: Special Conditions (Item H) of the permit, a plan for biological monitoring of the Clinch River, White Oak Creek (WOC), Northwest Tributary (NWT) of WOC, Melton Branch (MB), Fifth Creek, and First Creek shall be submitted for approval to the US Environmental Protection Agency (EPA) and the Tennessee Department of Health and Environment (TDHE) within 90 days of the effective date of the permit. The plan, which is referred to in Part 3 (H) of the permit as the Biological Monitoring Plan and Abatement Program (BMPAP), describes characterization monitoring studies to be conducted for the duration of the permit (5 years). In order to be consistent with the terminology used for the Biological Monitoring and Abatement Programs for the Oak Ridge Y-12 Plan and the Oak Ridge K-25 Plant, BMPAP will subsequently be referred to as the Biological Monitoring and Abatement Program (BMAP). The proposed BMAP outlined in this document is based on preliminary discussions held on December 9, 1985, between staff of Martin Marietta Energy Systems, Inc. (ORNL and Central Management), the US Department of Energy (DOE), EPA, and TDHE. 232 refs., 11 figs., 7 tabs.

  6. Oak Ridge National Laboratory Biological Monitoring and Abatement Program for White Oak Creek Watershed and the Clinch River

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M.; Adams, S.M.; Allison, L.J.; Blaylock, B.G.; Boston, H.L.; Huston, M.A.; Kimmel, B.L.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.; Walton, B.T.; Kitchings, J.T.; Olsen, C.R.

    1991-09-01

    On April 1, 1986, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge National Laboratory (ORNL) (EPA 1986). As specified in Part 3: Special Conditions (Item H) of the permit, a plan for biological monitoring of the Clinch River, White Oak Creek (WOC), Northwest Tributary (NWT) of WOC, Melton Branch (MB), Fifth Creek, and First Creek shall be submitted for approval to the US Environmental Protection Agency (EPA) and the Tennessee Department of Health and Environment (TDHE) within 90 days of the effective date of the permit. The plan, which is referred to in Part 3 (H) of the permit as the Biological Monitoring Plan and Abatement Program (BMPAP), describes characterization monitoring studies to be conducted for the duration of the permit (5 years). In order to be consistent with the terminology used for the Biological Monitoring and Abatement Programs for the Oak Ridge Y-12 Plan and the Oak Ridge K-25 Plant, BMPAP will subsequently be referred to as the Biological Monitoring and Abatement Program (BMAP). The proposed BMAP outlined in this document is based on preliminary discussions held on December 9, 1985, between staff of Martin Marietta Energy Systems, Inc. (ORNL and Central Management), the US Department of Energy (DOE), EPA, and TDHE. 232 refs., 11 figs., 7 tabs.

  7. Anodonta imbecillis copper sulfate reference toxicant/food test, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Two different foods, phytoplankton and YCT-Selenastrum (YCT-S), were tested in side by side tests to compare food quality. Toxicity testing of copper sulfate reference toxicant was conducted from July 6-15, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed LC{sub 50} values of 0.97 and 0.84 mg Cu/L for phytoplankton and YCT-S, respectively. Previously obtained values for phytoplankton tests are 2.02 and 1.12 mg Cu/L. Too few tests have been conducted with copper as the toxicant to determine a normal range of values. Although significant reduction in growth, compared to the phytoplankton control, was seen in all treatments, including the YCT-S Control, the consequence of this observation has not been established. Ninety-day testing of juvenile mussels exhibited large variations in growth within treatment and replicate groups.

  8. Comparison between four and seven-day Ceriodaphnia dubia survival and reproduction test protocols using oil refinery effluent samples

    Directory of Open Access Journals (Sweden)

    Eduardo Cyrino Oliveira-Filho

    2008-02-01

    Full Text Available The aim of this study was to compare the 7-day Ceriodaphnia dubia survival and reproduction test with a 4 day test to evaluate the toxicity of oil refinery effluents. Both shown identical NOECs with three of 6 tested samples. With one of the tested samples, the 4-day NOEC was one tested-concentration lower, and with the remaining two samples, it was one tested-concentration higher than those obtained using the 7-day protocol. Then results suggested that 4 and 7-day protocols were comparable to detect toxic effects.O objetivo do presente estudo foi comparar os protocolos de sobrevivência e reprodução de Ceriodaphnia dubia com 7 e 4 dias de duração, avaliando a toxicidade de amostras de efluentes de refinaria de petróleo. Ambos os protocolos apresentaram NOECs idênticos para 3 das 6 amostras testadas. Com uma das amostras o NOEC no ensaio de 4 dias ficou numa concentração testada menor, e nas duas amostras restantes ele ficou numa concentração testada maior do que os NOECs obtidos no ensaio de 7 dias. Esses resultados sugerem que os protocolos de ensaio com 4 e 7 dias são comparáveis quanto a sensibilidade para detectar o efeito tóxico crônico de efluentes de refinaria de petróleo.

  9. Revision of Campsurus violaceus species group (Ephemeroptera: Polymitarcyidae) with new synonymies and nomina dubia in Campsurus Eaton, 1868.

    Science.gov (United States)

    Molineri, C; Salles, F F; Emmerich, D

    2015-02-19

    The violaceus species group (formerly notatus species group) of Campsurus Eaton is revised. All the species in the violaceus group are diagnosed. A new species, C. molinai sp. nov. is described based on male imagos from Bolivia, characterized by their large and sclerotized penes. The violaceus group is proposed to include the following species: C. assimilis Traver, C. truncatus Ulmer (=C. mahunkai Puthz = C. melanocephalus Pereira & da Silva, new synonyms), C. violaceus Needham & Murphy (= C. meyeri Navás = C. notatus Needham & Murphy = C. paranensis Navás, new synonyms), C. emersoni Traver, C. decoloratus (Hagen), and C. molinai sp.nov. Additionally we consider the following species as nomina dubia: C. longicauda Navás, C. pfeifferi Navás, C. zikani Navás, C. albicans (orig. Ephemera albicans Percheron in Guerin & Percheron), C. burmeisteri Ulmer, C. dallasi Navás, C. quadridentatus Eaton, C. claudus Needham & Murphy, C. corumbanus Needham & Murphy, C. dorsalis (Burmeister), C. mutilus Needham & Murphy, and C. striatus Needham & Murphy. Given the results presented herein (five species synonymized and 12 proposed as nomina dubia), only 28 valid species remain in the genus Campsurus. Additionally, the nymphal stages of C. violaceus and C. truncatus are described and illustrated. Female adult genitalia (sockets) and eggs of C. decoloratus are described for the first time. Diagnoses, new country records, and redescriptions of selected characters of the imagos for the species of the violaceus group are given.

  10. Acute toxicity of six freshwater mussel species (Glochidia) to six chemicals: Implications for daphnids and Utterbackia imbecillis as surrogates for protection of freshwater mussels (Unionidae)

    Science.gov (United States)

    Milam, C.D.; Farris, J.L.; Dwyer, F.J.; Hardesty, D.K.

    2005-01-01

    Acute (24-h) toxicity tests were used in this study to compare lethality responses in early life stages (glochidia) of six freshwater mussel species, Leptodea fragilis, U. imbecillis, Lampsilis cardium, Lampsilis siliquoidea, Megalonaias nervosa, and Ligumia subrostrata, and two standard test organisms, Ceriodaphnia dubia and Daphnia magna. Concentrations of carbaryl, copper, 4-nonylphenol, pentachlorophenol, permethrin, and 2,4-D were used in acute exposures to represent different chemical classes and modes of action. The relative sensitivities of species were evaluated by ranking their LC 50 values for each chemical. We used these ranks to determine the extent to which U. imbecillis (one of the most commonly used unionids in toxicity tests) was representative of the tolerances of other mussels. We also calculated geometric mean LC50s for the families Unionidae and Daphnidae. Rankings of these data were used to assess the extent to which Daphnidae can be used as surrogates for freshwater mussels relative to chemical sensitivity. While no single chemical elicited consistently high or low toxicity estimates, carbaryl and 2,4-D were generally the least toxic to all species tested. No species was always the most sensitive, and Daphnidae were generally protective of Unionidae. Utterbackia imbecillis, while often proposed as a standard unionid mussel test species, did not always qualify as a sufficient surrogate (i.e., a substitute organism that often elicits similar sensitivity responses to the same contaminant exposure) for other species of mussels, since it was usually one of the more tolerant species in our rankings. U. imbecillis should be used as a surrogate species only with this caution on its relative insensitivity. ?? 2005 Springer Science+Business Media, Inc.

  11. Comparing the effectiveness of chronic water column tests with the crustaceans Hyalella azteca (order: Amphipoda) and Ceriodaphnia dubia (order: Cladocera) in detecting toxicity of current-use insecticides.

    Science.gov (United States)

    Deanovic, Linda A; Markiewicz, Dan; Stillway, Marie; Fong, Stephanie; Werner, Inge

    2013-03-01

    Standard U.S. Environmental Protection Agency laboratory tests are used to monitor water column toxicity in U.S. surface waters. The water flea Ceriodaphnia dubia is among the most sensitive test species for detecting insecticide toxicity in freshwater environments.Its usefulness is limited, however, when water conductivity exceeds 2,000 µS/cm (approximately 1 ppt salinity) and test effectiveness is insufficient. Water column toxicity tests using the euryhaline amphipod Hyalella azteca could complement C. dubia tests; however, standard chronic protocols do not exist. The present study compares the effectiveness of two water column toxicity tests in detecting the toxicity of two organophosphate (OP) and two pyrethroid insecticides: the short-term chronic C. dubia test, which measures mortality and fecundity, and a 10-d H. azteca test, which measures mortality and growth. Sensitivity was evaluated by comparing effect data, and end point variability was evaluated by comparing minimum significant differences. Tests were performed in synthetic water and filtered ambient water to quantify the influence of water matrix on effect concentrations. The H. azteca test detected pyrethroid toxicity far more effectively, while the C. dubia test was more sensitive to OPs. Among endpoints, H. azteca mortality was most robust. The results demonstrate that the H. azteca test is preferable when conductivity of water samples is 2,000 to 10,000 µS/cm or if contaminants of concern include pyrethroid insecticides.

  12. Chronic toxicity of parabens and their chlorinated by-products in Ceriodaphnia dubia.

    Science.gov (United States)

    Terasaki, Masanori; Abe, Ryoko; Makino, Masakazu; Tatarazako, Norihisa

    2015-01-01

    The chronic toxicity of 12 compounds of parabens and their chlorinated by-products was investigated using 7-day Ceriodaphnia dubia test under static renewal condition in order to generate information on how to disinfect by-products of preservatives that are discharged in aquatic systems. The mortality and inhibition of reproduction tended to increase with increasing hydrophobicity and decreased with the degree of chlorination of parabens. The EC50 values for mortality, offspring number, and first brood production ranged between 0.30-3.1, 0.047-12, and 1.3-6.3 mg L(-1) , respectively. For the number of neonates, the most sensitive endpoint, the no-observed-effect concentration (NOEC) and lowest-observed-effect concentration (LOEC) values ranged from 0.63 to 10 mg L(-1) and from 1.2 to 19 mg L(-1) , respectively. Methylparaben (MP), benzylparaben (BnP), and dichlorinated BnP (Cl2 BnP) elicited a significant decrease in offspring numbers even at their lowest concentration tested; the NOEC for these compounds was determined to be less than the lowest test concentration (1.3, 0.04, and 0.63 mg L(-1) for MP, BnP, and Cl2 BnP, respectively). Propylparaben (PP), chlorinated PP, isopropylparaben (iPP), and chlorinated iPP exhibited nonmonotonic concentration-dependent response; their NOEC and LOEC values could not be determined. The multivariate approach involving principal component analysis and hierarchical cluster analysis revealed four groups that corresponded to the toxicological profiles of parabens. Our results suggested that disinfection of parabens by chlorination could reduce aquatic toxicity of original compounds. The findings obtained in our study together with the data available on paraben concentrations in aquatic systems can be used to perform preliminary risk assessment by comparing the predicted environmental concentration (PEC) with the predicted no-effect concentration (PNEC) for the marine aquatic environment. The calculated PEC/PNEC ratios ranged from 0

  13. Acute and chronic toxicity of uranium compounds to Ceriodaphnia-Daphnia dubia

    Energy Technology Data Exchange (ETDEWEB)

    Pickett, J.B.; Specht, W.L.; Keyes, J.L.

    1993-03-31

    A study to determine the acute and chronic toxicity of uranyl nitrate, hydrogen uranyl phosphate, and uranium dioxide to the organism Ceriodaphnia dubia was conducted. The toxicity tests were conducted by two independent environmental consulting laboratories. Part of the emphasis for this determination was based on concerns expressed by SCDHEC, which was concerned that a safety factor of 100 must be applied to the previous 1986 acute toxicity result of 0.22 mg/L for Daphnia pulex, This would have resulted in the LETF release limits being based on an instream concentration of 0.0022 mg/L uranium. The NPDES Permit renewal application to SCDHEC utilized the results of this study and recommended that the LETF release limit for uranium be based an instream concentration of 0.004 mg/L uranium. This is based on the fact that the uranium releases from the M-Area LETF will be in the hydrogen uranyl phosphate form, or a uranyl phosphate complex at the pH (6--10) of the Liquid Effluent Treatment Facility effluent stream, and at the pH of the receiving stream (5.5 to 7.0). Based on the chronic toxicity of hydrogen uranyl phosphate, a lower uranium concentration limit for the Liquid Effluent Treatment Facility outfall vs. the existing NPDES permit was recommended: The current NPDES permit ``Guideline`` for uranium at outfall M-004 is 0.500 mg/L average and 1.0 mg/L maximum, at a design flowrate of 60 gpm. It was recommended that the uranium concentration at the M-004 outfall be reduced to 0.28 mg/L average, and 0.56 mg/L, maximum, and to reduce the design flowrate to 30 gpm. The 0.28 mg/L concentration will provide an instream concentration of 0.004 mg/L uranium. The 0.28 mg/L concentration at M-004 is based on the combined flows from A-014, A-015, and A-011 outfalls (since 1985) of 1840 gpm (2.65 MGD) and was the flow rate which was utilized in the 1988 NPDES permit renewal application.

  14. 三层板压印接头力学性能分析%Analysis of mechanics performances for clinched joint with three-layers

    Institute of Scientific and Technical Information of China (English)

    刘福龙; 何晓聪; 曾凯; 卢毅

    2015-01-01

    本文的研究目的是分析三层板不同搭接方式的压印接头的力学性能,主要采用试验方法对其进行研究,具体方法如下:首先对1.5 mmAA5052+1.5 mmSPCC+1.5 mmAA5052三层板不同配置方式下的压印接头进行静态力学性能测试,分析三层板压印接头的静态失效模式及其静强度;再对静态力学性能最优组进行动态疲劳性能测试,分析疲劳失效模式及其疲劳强度,并采用最小二乘法拟合获得接头力-寿命( F-N)方程.试验结果表明:静态失效为上板颈部断裂、中板内锁拉脱和混合失效三种模式;T-A型接头静强度最低,T-C型接头静强度最高.其中,T-C型接头疲劳失效模式为上板颈部先断裂,之后下板出现裂纹导致接头失效;T-C型接头上板颈部疲劳性能较差,当应力水平为静强度40%时,疲劳循环最多只能达到15965次,但是中板与下板连接可达到200万次.%This paper is concerning the effect of specimen configuration on the static mechanical behavior of clinched joints, three⁃layer joints in 1.5mmAA5052+1.5mmSPCC+1.5mmAA5052 were conducted. It indicated that the specimen configuration had a significant effect on the failure modes and static strength of three⁃layer clinched joints. The fatigue behavior of the specimens, which had the optimum static performance, has been investigated experimentally. The least square method was used to obtain the load⁃life (F-N) equations. Results reveal that three failure modes, fracture in the neck of upper sheet, interlock failure in the middle sheet and mixed failure, were presented in the static testing. Clinched joints in T-A type owned the lowest static strength;while clinched joints in T-C type had the highest static strength. The neck facture of the upper sheet of the clinched joints in T-C type occur initially in fatigue testing, and then cracks appeared on the bottom sheet. The clinched

  15. Data Management Plan and Functional System Design for the Information Management System of the Clinch River Remedial Investigation and Waste Area Grouping 6

    Energy Technology Data Exchange (ETDEWEB)

    Ball, T.; Brandt, C.; Calfee, J.; Garland, M.; Holladay, S.; Nickle, B.; Schmoyer, D.; Serbin, C.; Ward, M. [Oak Ridge National Lab., TN (United States)

    1994-03-01

    The Data Management Plan and Functional System Design supports the Clinch River Remedial Investigation (CRRI) and Waste Area Grouping (WAG) 6 Environmental Monitoring Program. The objective of the Data Management Plan and Functional System Design is to provide organization, integrity, security, traceability, and consistency of the data generated during the CRRI and WAG 6 projects. Proper organization will ensure that the data are consistent with the procedures and requirements of the projects. The Information Management Groups (IMGs) for these two programs face similar challenges and share many common objectives. By teaming together, the IMGs have expedited the development and implementation of a common information management strategy that benefits each program.

  16. Remedial investigation/feasibility study of the Clinch River/Poplar Creek operable unit. Volume 1, main text

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This document is the combined Remedial Investigation/Feasibility Study (RI/FS) Report for the Clinch River/Poplar Creek Operable Unit (CR/PC OU), an off-site OU associated with environmental restoration activities at the U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR). As a result of past, present, and potential future releases of hazardous substances into the environment, the ORR was placed on the National Priorities List in December 1989 (54 FR 48184). Sites on this list must be investigated for possible remedial action, as required by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 42 U.S.C. 9601, et seq.). This report documents the findings of the remedial investigation of this OU and the feasibility of potential remedial action alternatives. These studies are authorized by Sect. 117 of CERCLA and were conducted in accordance with the requirements of the National Contingency Plan (40 CFR Part 300). DOE, the U.S. Environmental Protection Agency (EPA), and the Tennessee Department of Environment and Conservation (TDEC) have entered into a Federal Facility Agreement (FFA), as authorized by Sect. 120 of CERCLA and Sects. 3008(h) and 6001 of the Resource Conservation and Recovery Act (RCRA) (42 U.S.C. 6901, et seq.). The purpose of this agreement is to ensure a coordinated and effective response for all environmental restoration activities occurring at the ORR. In addition to other responsibilities, the FFA parties mutually define the OU boundaries, set remediation priorities, establish remedial investigation priorities and strategies, and identify and select remedial actions. A copy of this FFA is available from the DOE Information Resource Center in Oak Ridge, Tennessee.

  17. Reproductive success and mortality rates of Ceriodaphnia dubia maintained in water from Upper Three Runs, Pen Branch, and Fourmile Branch

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L.

    1994-12-01

    It is anticipated that the new SRS NPDES permit will require toxicity testing of at numerous outfalls and receiving streams, using the standard test species, Ceriodaphnia dubia. Because SRS surface waters differ markedly from the standard culture water that is used for Ceriodaphnia, studies were undertaken to determine if unimpacted SRS surface waters will support this species. Three SRS surface waters were evaluated; Upper Three Runs at Road 8-1, Pen Branch at Road B, and Fourmile Branch at Road F. Toxicity tests were performed monthly on each water source for eleven months. All three water sources exhibited varying degrees of toxicity to Ceriodaphnia, with Pen Branch being the least toxic and Fourmile Branch being the most toxic. These results indicate that if in-stream toxicity testing is required, it may not be possible to separate the naturally occurring toxic effects of the receiving water from possible toxic effects of SRS effluents.

  18. USE OF CARBOXYLESTERASE ACTIVITY TO REMOVE PYRETHROID-ASSOCIATED TOXICITY TO CERIODAPHNIA DUBIA AND HYALELLA AZTECA IN TOXICITY IDENTIFICATION EVALUATIONS

    Science.gov (United States)

    Wheelock, Craig E.; Miller, Jeff L.; Miller, Mike J.; Phillips, Bryn M.; Huntley, Sarah A.; Gee, Shirley J.; Tjeerdema, Ronald S.; Hammock, Bruce D.

    2006-01-01

    Increases in the use and application of pyrethroid insecticides have resulted in concern regarding potential effects on aquatic ecosystems. Methods for the detection of pyrethroids in receiving waters are required to monitor environmental levels of these insecticides. One method employed for the identification of causes of toxicity in aquatic samples is the toxicity identification evaluation (TIE); however, current TIE protocols do not include specific methods for pyrethroid detection. Recent work identified carboxylesterase treatment as a useful method for removing/detecting pyrethroid-associated toxicity. The present study has extended this earlier work and examined the ability of carboxylesterase activity to remove permethrin- and bifenthrin-associated toxicity to Ceriodaphnia dubia and Hyalella azteca in a variety of matrices, including laboratory water, Sacramento River (CA, USA) water, and Salinas River (CA, USA) interstitial water. Esterase activity successfully removed 1,000 ng/L of permethrin-associated toxicity and 600 ng/L of bifenthrin-associated toxicity to C. dubia in Sacramento River water. In interstitial water, 200 ng/L of permethrin-associated toxicity and 60 ng/L of bifenthrin-associated toxicity to H. azteca were removed. The selectivity of the method was validated using heat-inactivated enzyme and bovine serum albumin, demonstrating that catalytically active esterase is required. Further studies showed that the enzyme is not significantly inhibited by metals. Matrix effects on esterase activity were examined with municipal effluent and seawater in addition to the matrices discussed above. Results confirmed that the esterase retains catalytic function in a diverse array of matrices, suggesting that this technique can be adapted to a variety of aquatic samples. These data demonstrate the utility of carboxylesterase treatment as a viable step to detect the presence of pyrethroids in receiving waters. PMID:16629136

  19. Fluctuación diurna del contenido de vitamina C en hojas de Myrciaria dubia “camu camu”

    Directory of Open Access Journals (Sweden)

    Franz Correa Meléndez

    2013-12-01

    Full Text Available Myrciaria dubia “camu camu” es un frutal del trópico amazónico caracterizado por sus frutos con gran contenido de vitamina C, siendo considerado un producto importante del país. Sin embargo, hay pocos reportes sobre el metabolismo y transporte de vitamina C en esta especie. El objetivo de la investigación fue determinar la fluctuación diurna del contenido de vitamina C en hojas de M. dubia “camu camu”. Las hojas se colectaron de la colección de germoplasma de “camu camu” del INIA a las 2, 6, 10, 14, 18 y 22 horas; de cuatro plantas y en tres fechas diferentes. La vitamina C fue extraída de las hojas con un método estandarizado en el laboratorio y se cuantificó mediante espectrofotometría a 530nm, previa reacción con 2,6-diclorofenolindofenol. Los resultados muestran que el contenido de vitamina C de las hojas de “camu camu” fue en promedio 231±35 mg vitamina C/100g de hoja. Además, el contenido de vitamina C en las hojas del “camu camu” mostró fluctuación diurna, siendo menor a las 6 horas y mayor a las 2 y 14 horas del día. También, se registraron concentraciones intermedias en horas de menor o ausencia de radiación solar (235±17 y 237±35 mg vitamina C/100g de hoja a las 18 y 22 horas respectivamente. Se concluye que existe alto contenido de vitamina C en las hojas del “camu camu” y que este contenido presenta fluctuación diurna.

  20. Toxicity of waters from the Rochester Embayment Area of Concern to the plankton species Pseudokirchneriella subcapitata and Ceriodaphnia dubia

    Science.gov (United States)

    Baldigo, Barry P.; Duffy, Brian T.; Smith, Alexander J; George, Scott D.

    2016-01-01

    The lower Genesee River and Rochester Embayment of Lake Ontario are a designated Area of Concern (AOC) under the binational Great Lakes Water Quality Agreement. The “degradation of phytoplankton and zooplankton populations” or plankton Beneficial Use Impairment (BUI) was classified as unknown and in need of further assessment in this AOC because water quality data suggested plankton communities could be effected and community data were either unavailable or indicated impacts. The plankton BUI may now be obsolete because local contaminant sources have been largely eliminated. The present study was conducted between July 2013 and August 2014 to assess the BUI-removal criteria: “AOC plankton bioassays confirm that toxicity in ambient waters (i.e., no growth inhibition) is not significantly higher than comparable non-AOC controls”. Acute and chronic toxicity of waters from 13 sites were quantified seasonally using standardized bioassays with the green alga Pseudokirchneriella subcapitata and water flea Ceriodaphnia dubia to test the hypothesis that toxicity of waters from AOC sites was not higher than that of waters from comparable non-AOC reference sites. Survival and reproduction of C. dubia did not differ significantly between site types, systems, or months. The growth of P. subcapitata did not differ between site types, but differed among systems and months. All results indicate that waters from AOC sites were no more toxic to both plankton species than waters from reference sites. Assuming test species represent natural plankton assemblages, water quality should not negatively affect survival and growth of resident plankton populations in the Rochester Embayment AOC.

  1. Remedial investigation/feasibility study of the Clinch River/Poplar Creek operable unit. Volume 3: Appendixes E and F -- Risk assessment information

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This report presents the findings of an investigation into contamination of the Clinch River and Poplar Creek near the US Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) in eastern Tennessee. For more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities at the ORR. In 1989, the ORR was placed on the National Priorities List (NPL), established and maintained under the federal Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Under CERCLA, NPL sites must be investigated to determine the nature and extent of contamination at the site, assess the risk to human health and the environment posed by the site, and, if necessary, identify feasible remedial alternatives that could be used to clean the site and reduce risk. To facilitate the overall environmental restoration effort at the ORR, CERCLA activities are being implemented individually as distinct operable units (OUs). This document is the combined Remedial Investigation and Feasibility Study Report for the Clinch River/Poplar Creek OU.

  2. Remedial investigation/feasibility study of the Clinch River/Poplar Creek Operable Unit. Volume 3. Risk assessment information. Appendixes E, F

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This report presents the findings of an investigation into contamination of the Clinch River and Poplar Creek near the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) in eastern Tennessee. For more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities at the ORR. In 1989, the ORR was placed on the National Priorities List (NPL), established and maintained under the federal Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Under CERCLA, NPL sites must be investigated to determine the nature and extent of contamination at the site, assess the risk to human health and the environment posed by the site, and, if necessary, identify feasible remedial alternatives that could be used to clean the site and reduce risk. To facilitate the overall environmental restoration effort at the ORR, CERCLA activities are being implemented individually as distinct operable units (OUs). This document is Volume 3 of the combined Remedial Investigation and Feasibility Study Report for the Clinch River/Poplar Creek OU.

  3. Remedial investigation/feasibility study of the Clinch River/Poplar Creek Operable Unit. Volume 2. Biota and representative concentrations of contaminants. Appendixes A, B, C, D

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This report presents the findings of an investigation into contamination of the Clinch River and Poplar Creek near the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) in eastern Tennessee. For more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities at the ORR. In 1989, the ORR was placed on the National Priorities List (NPL), established and maintained under the federal Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Under CERCLA, NPL sites must be investigated to determine the nature and extent of contamination at the site, assess the risk to human health and the environment posed by the site, and, if necessary, identify feasible remedial alternatives that could be used to clean the site and reduce risk. To facilitate the overall environmental restoration effort at the ORR, CERCLA activities are being implemented individually as distinct operable units (OU`s). This document is the combined Remedial Investigation and Feasibility Study Report for the Clinch River/Poplar Creek OU.

  4. Remedial investigation/feasibility study of the Clinch River/Poplar Creek Operable Unit. Volume 5. Appendixes J, K, L, M, and N-other supporting information

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This report presents the findings of an investigation into contamination of the Clinch River and Poplar Creek near the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) in eastern Tennessee. For more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities at the ORR. In 1989, the ORR was placed on the National Priorities List (NPL), established and maintained under the federal Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Under CERCLA, NPL sites must be investigated to determine the nature and extent of contamination at the site, assess the risk to human health and the environment posed by the site, and, if necessary, identify feasible remedial alternatives that could be used to clean the site and reduce risk. To facilitate the overall environmental restoration effort at the ORR, CERCLA activities are being implemented individually as distinct operable units (OUs). This document is Volume 5 of the combined Remedial Investigation and Feasibility Study Report for the Clinch River/Poplar Creek OU.

  5. Geographic Place Names, GNIS data for Atkinson, Bacon, Ben Hill, Berrien, Brantley, Brooks, Charlton, Clinch, Coffee, Cook, Echols, Irwin, Lanier, Lowndes, Pierce, Tift, Turner, Ware counties., Published in 1999, 1:7200 (1in=600ft) scale, Southern Georgia Regional Commission.

    Data.gov (United States)

    NSGIC Regional | GIS Inventory — Geographic Place Names dataset current as of 1999. GNIS data for Atkinson, Bacon, Ben Hill, Berrien, Brantley, Brooks, Charlton, Clinch, Coffee, Cook, Echols, Irwin,...

  6. Remedial investigation/feasibility study for the Clinch River/Poplar Creek operable unit. Volume 5. Appendixes G, H, I, J

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The Quality Assurance/Quality Control (QA/QC) Program for Phase 2 of the Clinch River Remedial Investigation (CRRI) was designed to comply with both Department of Energy (DOE) Order 5700.6C and Environmental Protection Agency (EPA) QAMS-005/80 (EPA 1980a) guidelines. QA requirements and the general QA objectives for Phase 2 data were defined in the Phase 2 Sampling and Analysis Plan (SAP)-Quality Assurance Project Plan, and scope changes noted in the Phase 2 Sampling and Analysis Plan Addendum. The QA objectives for Phase 2 data were the following: (1) Scientific data generated will withstand scientific and legal scrutiny. (2) Data will be gathered using appropriate procedures for sample collection, sample handling and security, chain of custody (COC), laboratory analyses, and data reporting. (3) Data will be of known precision and accuracy. (4) Data will meet data quality objectives (DQOs) defined in the Phase 2 SAP.

  7. Phase 1 data summary report for the Clinch River Remedial Investigation: Health risk and ecological risk screening assessment. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Cook, R.B.; Adams, S.M.; Beauchamp, J.J.; Bevelhimer, M.S.; Blaylock, B.G.; Brandt, C.C.; Ford, C.J.; Frank, M.L.; Gentry, M.J.; Holladay, S.K.; Hook, L.A.; Levine, D.A.; Longman, R.C.; McGinn, C.W.; Skiles, J.L.; Suter, G.W.; Williams, L.F.

    1992-12-01

    The Clinch River Remedial Investigation (CRRI) is designed to address the transport, fate, and distribution of waterborne contaminants released from the US Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) and to assess potential risks to human health and the environment associated with these contaminants. The contaminants released since the early 1940s include a variety of radionuclides, metals, and organic compounds. The purpose of this report is to summarize the results of Phase 1 of the CRRI. Phase 1 was designed to (1) obtain high-quality data to confirm existing historical data for contaminant levels in fish, sediment, and water from the CR/WBR; (2) determine the in the range of contaminant concentrations present river-reservoir system; (3) identify specific contaminants of concern; and (4) establish the reference (background) concentrations for those contaminants.

  8. Static renewal tests using Anodonta imbecillis (freshwater mussels). Anodonta imbecillis QA test 2, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected August 14 from Poplar Creek Miles 6.0 and 4.3 was conducted from August 24--September 2, 1993. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments. Attachments to this report include: Chain of custody form -- original; Toxicity test bench sheets and statistical analyses; and Ammonia analysis request and results.

  9. Static renewal tests using Anodonta imbecillis (freshwater mussels). Anodonta imbecillis QA test 4, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1994-12-31

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organisms quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected September 8 from Poplar Creek Miles 6.0 and 1.0 was conducted September 13--22, 1994. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments. Attachments to this report include: Chain of custody form -- original; Toxicity test bench sheets; Ammonia analysis request and results; and Meter calibration log sheets.

  10. Static renewal tests using Anodonta imbecillus (freshwater mussels). Anodonta imbecillis copper sulfate reference toxicant test, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Toxicity testing of copper sulfate reference toxicant was conducted from May 12--21, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed an LC{sub 50} value of 1.12 mg Cu/L which is lower than the value of 2.02 mg Cu/L obtained in a previous test. Too few tests have been conducted with copper as the toxicant to determine a normal range of values. Attachments to this report include: Toxicity test bench sheets and statistical analyses; Copper analysis request and results; and Personnel training documentation.

  11. Static renewal tests using Anodonta imbecillis (freshwater mussels). Anodonta imbecillis QA test 3, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1994-12-31

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected May 5 from Poplar Creek Miles 6.0 and 2.9 was conducted from May 10--19, 1994. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments. Attachments to this report include: Chain of custody form -- original; Toxicity test bench sheets; Ammonia analysis request and results; Meter calibration log sheets; and Training documentation forms.

  12. 1-methylmalate from camu-camu (Myrciaria dubia) suppressed D-galactosamine-induced liver injury in rats.

    Science.gov (United States)

    Akachi, Toshiyuki; Shiina, Yasuyuki; Kawaguchi, Takumi; Kawagishi, Hirokazu; Morita, Tatsuya; Sugiyama, Kimio

    2010-01-01

    To evaluate the protective effects of fruit juices against D-galactosamine (GalN)-induced liver injury, lyophilized fruit juices (total 12 kinds) were fed to rats for 7 d, and then we evoked liver injury by injecting GalN. The juice of camu-camu (Myrciaria dubia) significantly suppressed GalN-induced liver injury when the magnitude of liver injury was assessed by plasma alanine aminotransferase and aspartate aminotransferase activities, although some other juices (acerola, dragon fruit, shekwasha, and star fruit) also tended to have suppressive effects. An active compound was isolated from camu-camu juice by solvent fractionation and silica gel column chromatography. The structure was determined to be 1-methylmalate. On the other hand, malate, 1,4-dimethylmalate, citrate, and tartrate had no significant effect on GalN-induced liver injury. It is suggested that 1-methylmalate might be a rather specific compound among organic acids and their derivatives in fruit juices in suppressing GalN-induced liver injury.

  13. Ontogeny of hemocyanin in the ovoviviparous cockroach Blaptica dubia suggests an embryo-specific role in oxygen supply.

    Science.gov (United States)

    Pick, Christian; Schneuer, Marco; Burmester, Thorsten

    2010-05-01

    For a long time it had been assumed that specific oxygen transport proteins are absent in insects. Only recently it has been demonstrated that hemocyanins occur in the hemolymph of many ametabolous and hemimetabolous insect taxa, but not in the Eumetabola (Hemiptera+Holometabola). Therefore, the loss of respiratory hemocyanin in insects is not correlated with the evolution of an efficient tracheal system. The specific contribution of hemocyanin to oxygen supply in insects, however, has remained uncertain. Here we investigate the stage-specific expression of hemocyanin in the ovoviviparous cockroach Blaptica dubia (Blattaria), which consists of two distinct subunit types (Hc1 and Hc2). Employing quantitative real-time RT-PCR and Western blotting, we showed that the expression of hemocyanin is restricted to late embryos, thus being detectable also in whole female extracts and oothecae. Hemocyanin protein is also present in 1st instar nymphs, but not in later developmental stages. The ontogeny of hemocyanin in cockroaches is distinct from that known from Zygentoma and Plecoptera, in which hemocyanin occurs in both nymphal and adult stages. Our findings suggest a specific role of hemocyanin in embryonic cockroaches, which may be related to an enhanced oxygen supply in the oothecae. For some reason, the fundamental physiological changes associated to the evolution of holometaboly have made hemocyanin unnecessary.

  14. Post-harvest conservation of camu–camu fruits (Myrciaria dubia (Kunth Mc Vaugh using different temperatures and packages

    Directory of Open Access Journals (Sweden)

    Maria Luiza GRIGIO

    2015-12-01

    Full Text Available Abstract The camu-camu tree (Myrciaria dubia (Kunth Mc Vaugh is fruit-bearing tree belonging to the family Myrtaceae. This work was conducted with the purpose of evaluating the type of storage temperature and package which allow better conservation of the quality attributes of camu-camu. The experimental design utilized was the completely randomized with three replications in a factorial arrangement (3x3x8, constituted of three different storage temperatures (laboratory ambiente or 25 ± 2 °C, 15 °C and 20 °C, three types of packages (no package, PET and PVC and fourteen days’ storage, the fruits being analyzed every two days. The fruits were evaluated as to fresh mass loss, pH, soluble solids contents, titrable acidity, ascorbic acid, carotenoids, anthocyanins, chlorophylls A and B and maturation index (SS/AT. According to the results obtained, the quality attributes and ascorbic acid content were conserved for longer time in the fruits stored on PVC-film covered expanded polystyrene trays at 15 °C. It follows that the best temperature for the storage of camu-camu is 15 °C and the package that best keeps its quality attributes is the PVC-film covered expanded polystyrene tray.

  15. El remachado de embutido: Una opción interesante para la unión de láminas. // Clinching: A good option to joining metals sheet.

    Directory of Open Access Journals (Sweden)

    F. Hernández González

    2003-05-01

    Full Text Available Entre otros métodos tradicionalmente utilizados para lograr la unión de láminas se encuentran: la soldadura, el remachado,y el atornillado. Actualmente, esta siendo utilizado una tecnología de unión que alcanza el mismo objetivo sin el empleo deelemento adicional alguno: el remachado de embutido (clinching. Se describen en este trabajo las característicasprincipales del método, sus ventajas, los tipos más comunes, así como las herramientas utilizadas en los mismos.Palabras claves: Remachado de embutido, unión, punzón, matriz, lamina.________________________________________________________________________________Abstract.Among other traditionally methods used for joining sheets, we can find welding, riveting and screening. At present, a newjoining technology to fulfill the same goal, but using no additional element: clinching. The main characteristics of thismethod, its advantages, the standard types, as well as tools used in the process are described in this paper.Key words: Clinching, joining, parameters of work, punch, die, metal sheet.

  16. Inducción de la biosíntesis local de antocianinas en frutos de Myrciaria dubia mediante lesiones mecánicas

    Directory of Open Access Journals (Sweden)

    Daniel Motta-Santillán

    2015-01-01

    Full Text Available En las plantas las antocianinas cumplen roles fundamentales en sus interacciones con el medio ambiente, son una de las líneas de defensa contra los radicales libres, la radiación ultravioleta y el ataque de patógenos. Observaciones realizadas muestran que los frutos de M. dubia acumulan antocianinas alrededor de lesiones mecánicas probablemente causadas por insectos. Por tanto, hemos probado la hipótesis que produciendo lesiones mecánicas en frutos verdes de M. dubia se induce la biosíntesis local de antocianinas. De tres plantas en fructificación de la colección de germoplasma del INIA se seleccionaron aleatoriamente 40 frutos verdes (25 ± 5 mm de Ø y se causaron lesiones mecánicas con estilete o bisturí al 75% de ellos. Posteriormente, se registró el porcentaje de acumulación de antocianinas por área superficial del fruto a las 0, 24, 48 y 72 horas. Se observó acumulación de antocianinas en ~10% (24 horas, ~30% (48 horas y ~70% (72 horas del área superficial de los frutos. En conclusión, las lesiones mecánicas causadas en frutos de M. dubia inducen la biosíntesis local de antocianinas, probablemente como un mecanismo de defensa efectivo desarrollado por esta especie. La comprensión de los mecanismos moleculares implicados en esta respuesta fisiológica nos permitirá establecer las bases para la mejora genética de esta especie.

  17. Inducción de la biosíntesis local de antocianinas en frutos de Myrciaria dubia mediante lesiones mecánicas

    Directory of Open Access Journals (Sweden)

    Daniel Motta Santillán

    2014-12-01

    Full Text Available En las plantas las antocianinas cumplen roles fundamentales en sus interacciones con el medio ambiente, son una de las líneas de defensa contra los radicales libres, la radiación ultravioleta y el ataque de patógenos. Observaciones realizadas muestran que los frutos de M. dubia acumulan antocianinas alrededor de lesiones mecánicas probablemente causadas por insectos. Por tanto, hemos probado la hipótesis que produciendo lesiones mecánicas en frutos verdes de M. dubia se induce la biosíntesis local de antocianinas. De tres plantas en fructificación de la colección de germoplasma del INIA se seleccionaron aleatoriamente 40 frutos verdes (25 ± 5 mm de Ø y se causaron lesiones mecánicas con estilete o bisturí al 75% de ellos. Posteriormente, se registró el porcentaje de acumulación de antocianinas por área superficial del fruto a las 0, 24, 48 y 72 horas. Se observó acumulación de antocianinas en ~10% (24 horas, ~30% (48 horas y ~70% (72 horas del área superficial de los frutos. En conclusión, las lesiones mecánicas causadas en frutos de M. dubia inducen la biosíntesis local de antocianinas, probablemente como un mecanismo de defensa efectivo desarrollado por esta especie. La comprensión de los mecanismos moleculares implicados en esta respuesta fisiológica nos permitirá establecer las bases para la mejora genética de esta especie.

  18. Toxicity of cobalt-complexed cyanide to Oncorhynchus mykiss, Daphnia magna, and Ceriodaphnia dubia: Potentiation by ultraviolet radiation and attenuation by dissolved organic carbon and adaptive UV tolerance

    Science.gov (United States)

    Little, Edward E.; Calfee, Robin D.; Theodorakos, Peter M.; Brown, Zoe Ann; Johnson, Craig A.

    2007-01-01

    BackgroundCobalt cyanide complexes often result when ore is treated with cyanide solutions to extract gold and other metals. These have recently been discovered in low but significant concentrations in effluents from gold leach operations. This study was conducted to determine the potential toxicity of cobalt-cyanide complexes to freshwater organisms and the extent to which ultraviolet radiation (UV) potentiates this toxicity. Tests were also conducted to determine if humic acids or if adaptation to UV influenced sensitivity to the cyanide complexes.MethodsRainbow trout (Oncorhynchus mykiss), Daphnia magna, and Ceriodaphnia dubia were exposed to potassium hexacyanocobaltate in the presence and absence of UV radiation, in the presence and absence of humic acids. Cyano-cobalt exposures were also conducted with C. dubia from cultures adapted to elevated UV.ResultsWith an LC50 concentration of 0.38 mg/L, cyanocobalt was over a 1000 times more toxic to rainbow trout in the presence of UV at a low, environmentally relevant irradiance level (4 μW/cm2 as UVB) than exposure to this compound in the absence of UV with an LC50 of 112.9 mg/L. Toxicity was immediately apparent, with mortality occurring within an hour of the onset of exposure at the highest concentration. Fish were unaffected by exposure to UV alone. Weak-acid dissociable cyanide concentrations were observed in irradiated aqueous solutions of cyanocobaltate within hours of UV exposure and persisted in the presence of UV for at least 96 hours, whereas negligible concentrations were observed in the absence of UV. The presence of humic acids significantly diminished cyanocobalt toxicity to D. magna and reduced mortality from UV exposure. Humic acids did not significantly influence survival among C. dubia. C. dubia from UV-adapted populations were less sensitive to metallocyanide compounds than organisms from unadapted populations.ConclusionsThe results indicate that metallocyanide complexes may pose a hazard to

  19. Names for Ixodidae (Acari: Ixodoidea): valid, synonyms, incertae sedis, nomina dubia, nomina nuda, lapsus, incorrect and suppressed names--with notes on confusions and misidentifications.

    Science.gov (United States)

    Guglielmone, Alberto A; Nava, Santiago

    2014-02-24

    A major, but not exhaustive, literature revision has been made to compile the names of Ixodidae from Linnaeus to present. Names are classified as valid, synonyms, lapsus, incertae sedis, nomina dubia, nomina nuda, incorrect and suppressed. Notes are included for confusions and misidentifications among different tick species. The lists included in this study are neither aimed to be consensual nor focusing to stabilize nomenclature, but rather part of a discussion on the species forming Ixodidae and a potential aid for research on tick taxonomy and phylogeny.

  20. Acute toxicity and accumulation of ZnO NPs in Ceriodaphnia dubia: Relative contributions of dissolved ions and particles.

    Science.gov (United States)

    Bhuvaneshwari, M; Iswarya, V; Nagarajan, R; Chandrasekaran, N; Mukherjee, Amitava

    2016-08-01

    Although the ecotoxicological effects of various metal oxide nanoparticles on aquatic organisms are being actively studied, the contributions of particles and dissolved ions towards toxicity are still not well understood. The current study aims to assess the contribution of ZnO NP(particle) and ZnO NP(ion) to the overall toxicity and accumulation of ZnO NP(total) in Ceriodaphnia dubia. The aggregation and dissolution kinetics were studied for three different sizes (50nm, 100nm and bulk) of ZnO particles at 0.05, 0.12, 0.25 and 0.5mg/L concentrations in the sterile lake water medium at 6, 12, 24, and 48h intervals. The 48h LC50 of ZnO NP(total) was found to be 0.431, 0.605 and 0.701mg/L for 50, 100nm and bulk particles exposure. However, LC50 of Zn(ion) was found to be 1.048, 1.343 and 2.046mg/L for dissolved ions from different sizes (50nm, 100nm, and bulk) of ZnO particles. At LC50 concentration, the accumulation of 90-95% was noted for the NP(particles) across the sizes employed, while only about 4-5% contribution was from the NP(ion) to the overall accumulation NP(total). The relative contribution of ZnO NP(ion) to overall toxicity and accumulation was found to be lesser than that of ZnO NP(particles) across the sizes used in the study.

  1. Fractionation of fulvic acid by iron and aluminum oxides--influence on copper toxicity to Ceriodaphnia dubia.

    Science.gov (United States)

    Smith, Kathleen S; Ranville, James F; Lesher, Emily K; Diedrich, Daniel J; McKnight, Diane M; Sofield, Ruth M

    2014-10-21

    This study examines the effect on aquatic copper toxicity of the chemical fractionation of fulvic acid (FA) that results from its association with iron and aluminum oxyhydroxide precipitates. Fractionated and unfractionated FAs obtained from streamwater and suspended sediment were utilized in acute Cu toxicity tests on Ceriodaphnia dubia. Toxicity test results with equal FA concentrations (6 mg FA/L) show that the fractionated dissolved FA was 3 times less effective at reducing Cu toxicity (EC50 13 ± 0.6 μg Cu/L) than were the unfractionated dissolved FAs (EC50 39 ± 0.4 and 41 ± 1.2 μg Cu/L). The fractionation is a consequence of preferential sorption of molecules having strong metal-binding (more aromatic) moieties to precipitating Fe- and Al-rich oxyhydroxides, causing the remaining dissolved FA to be depleted in these functional groups. As a result, there is more bioavailable dissolved Cu in the water and hence greater potential for Cu toxicity to aquatic organisms. In predicting Cu toxicity, biotic ligand models (BLMs) take into account dissolved organic carbon (DOC) concentration; however, unless DOC characteristics are accounted for, model predictions can underestimate acute Cu toxicity for water containing fractionated dissolved FA. This may have implications for water-quality criteria in systems containing Fe- and Al-rich sediment, and in mined and mineralized areas in particular. Optical measurements, such as specific ultraviolet absorbance at 254 nm (SUVA254), show promise for use as spectral indicators of DOC chemical fractionation and inferred increased Cu toxicity.

  2. Morphological and genetic diversity of camu-camu [Myrciaria dubia (Kunth) McVaugh] in the Peruvian Amazon.

    Science.gov (United States)

    Šmíd, Jan; Kalousová, Marie; Mandák, Bohumil; Houška, Jakub; Chládová, Anna; Pinedo, Mario; Lojka, Bohdan

    2017-01-01

    Camu-camu [Myrciaria dubia (Kunth) McVaugh] is currently an important and promising fruit species grown in the Peruvian Amazon, as well as in Brazil, Colombia, and Bolivia. The species is valued for its high content of fruit-based vitamin C. Large plantations have been established only in the last two decades, and a substantial part of the production is still obtained by collecting fruits from the wild. Domestication of the species is at an early stage; most farmers cultivate the plants without any breeding, or only through a simple mass selection process. The main objective of the study was to characterize morphological and genetic variation within and among cultivated and natural populations of camu-camu in the Peruvian Amazon. In total, we sampled 13 populations: ten wild in the Iquitos region, and three cultivated in the Pucallpa region in the Peruvian Amazon. To assess the genetic diversity using seven microsatellite loci, we analyzed samples from ten individual trees per each population (n = 126). Morphological data was collected from five trees from each population (n = 65). The analysis did not reveal statistically significant differences for most of the morphological descriptors. For wild and cultivated populations, the observed heterozygosity was 0.347 and 0.404 (expected 0.516 and 0.506), and the fixation index was 0.328 and 0.200, respectively. Wild populations could be divided into two groups according to the UPGMA and STRUCTURE analysis. In cultivated populations, their approximate origin was determined. Our findings indicate a high genetic diversity among the populations, but also a high degree of inbreeding within the populations. This can be explained by either the isolation of these populations from each other or the low number of individuals in some populations. This high level of genetic diversity can be explored for the selection of superior individuals for further breeding.

  3. Static renewal tests using Anodonta imbecillis (freshwater mussels). Anodonta imbecillis QA test 1, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA and CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments to provide a quality assurance mechanism for test organism quality and overall performance of the test. In addition, testing included procedures comparing daily renewal versus non-renewal of test sediments. Testing of sediment samples collected July 15 from Poplar Creek Miles 6.0 and 5.1 was conducted from July 21--30, 1993. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments. Side by side testing of sediments with daily sediment renewal and no sediment renewal showed no differences between methods. This may be due to the absence of toxicity in both samples and may not reflect true differences between the two methods for toxic sediment. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Ammonia analysis request and results.

  4. Static renewal tests using Anodonta imbecillis (freshwater mussels). Anodonta imbecillis copper sulfate reference toxicant/food test, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Two different foods, phytoplankton and YCT-Selenastrum (YCT-S), were tested in side by side tests to compare food quality. Toxicity testing of copper sulfate reference toxicant was conducted from July 6--15, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Although significant reduction in growth, compared to the phytoplankton control, was seen in all treatments, including the YCT-S Control, the consequence of this observation has not been established. Ninety-day testing of juvenile mussels exhibited large variations in growth within treatment and replicate groups. Attachments to this report include: Toxicity test bench sheets and statistical analyses; and Copper analysis request and results.

  5. Aproveitamento do camu-camu (Myrciaria dubia para produção de bebida alcoólica fermentada The use of camu-camu (Myrciaria dubia for the production of a fermented alcoholic beverage

    Directory of Open Access Journals (Sweden)

    Roberto Nobuyuki Maeda

    2003-01-01

    Full Text Available O elevado teor de ácido ascórbico no camu-camu (Myrciaria dubia McVaugh, Myrtaceae desperta o interesse de extrativistas, agricultores e consumidores, e leva à necessidade de desenvolvimento de tecnologias adequadas para produção em terra firme e aproveitamento industrial do fruto. Este trabalho teve por objetivo verificar a adequação do camu-camu para a produção de bebida alcoólica fermentada, assim como o efeito do branqueamento do fruto e da incorporação da casca à polpa nas características nutricionais e sensoriais da bebida. Os frutos foram separados em quatro lotes, sendo dois branqueados (90 ºC por 7 min. Após a despolpa, as cascas de um lote de cada tratamento (com e sem branqueamento foram incorporadas às respectivas polpas e avaliadas quanto à composição química (umidade, pH, acidez, sólidos solúveis, açúcares, ácido ascórbico, compostos fenólicos, antocianinas e flavonóides. Após a correção do mosto com açúcar, pasteurização, fermentação (25 dias, trasfega, pasteurização (70 ºC por 15 min, filtragem e clarificação, as bebidas foram avaliadas quanto a composição química, edulcoradas e submetidas à análise sensorial. O branqueamento reduziu a concentração de ácido ascórbico das polpas (33 % e a agregação da casca aumentou os teores de matéria seca (39 % polpa, ácido ascórbico (33 % na polpa, 23 % no mosto e 50 % na bebida e fenólicos (50 % bebida. O perfil sensorial e a aceitabilidade sugerem que o camu-camu é adequado para a produção de bebida alcoólica fermentada e que a agregação da casca à polpa contribuiu positivamente para a aceitabilidade (6,7 com casca e 6,2 sem casca, na escala de 9 pontos. As bebidas apresentaram flavor característico do fruto, limpidez, coloração vermelho-laranjada e sabor agradável.The high levels of ascorbic acid in camu-camu (Myrciaria dubia McVaugh, Myrtaceae have stimulated interest of extractivists, farmers and consumers. This has led

  6. Esterases no exame da estrutura populacional de Camu-camu (Myrciaria dubia (Kunth McVaugh-Myrtaceae Esterases for examining the population structure of Camu-camu (Myrciaria dubia (Kunth McVaugh-Myrtaceae

    Directory of Open Access Journals (Sweden)

    Aylton Saturnino Teixeira

    2004-01-01

    Full Text Available Dois sistemas enzimáticos (esterase e esterase-D, analisados pela técnica de eletroforese em gel de amido, em folhas jovens de plantas cultivadas em terra firme, de sementes provenientes de três amostras de populações naturais de camu-camu, Myrciaria dubia (Kunth McVaugh-Myrtaceae, procedentes de Iquitos, Boa Vista e Uatumã, revelaram a presença de 6 locos: Est-1, Est-2, Est-3, Est-4, Est-D1 e Est-D2. Dois dos seis locos gênicos examinados no presente estudo (Est-3 e Est-D2 mostraram-se polimórficos, sendo desse modo considerados valiosos no estudo de caracterização da estrutura populacional da espécie. Os padrões de polimorfismo revelados nos locos Est-3 e Est-D2 de camu-camu, são típicos de enzimas monoméricas e diméricas, respectivamente. O loco Est-3 apresentou um grande desbalanço genético dentro e entre as amostras populacionais examinadas, devido ao excessivo número observado de plantas heterozigóticas em relação ao número esperado. O loco Est-D2 apresentou um polimorfismo exclusivo para os alelos Est-D2¹,Est-D2² e Est-D2³, e um bom balanço genético na amostra populacional de Uatumã. Em função disso, dentre os demais locos gênicos aqui investigados, o loco Est-D2 parece ser o mais adequado para identificação e delimitação de prováveis estoques de camu-camu. Portanto, recomenda-se que esse loco esteja presente na lista dos marcadores isoenzimáticos a serem usados em futuras prospecções sobre genética populacional dessa espécie na região amazônica. Dados sobre a distribuição das freqüências alélicas, estimativas das distâncias genéticas, e estimativas de variação genética nos 6 locos de esterases examinados, foram eficazes na demonstração de diferenças genéticas entre as amostras populacionais examinadas da espécie. Os maiores valores de heterozigozidade média (0,1353; proporção de locos polimórficos (0,33 e número médio de alelos por loco (1,33 revelados na amostra

  7. Caracterización morfológica y molecular de Leptochloa dubia (Poaceae en Chihuahua, México

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    Carlos Morales-Nieto

    2015-08-01

    Full Text Available El gigante [Leptochloa dubia(Kunth Nees.] es una importante gramínea forrajera nativa de México, cuyas poblaciones naturales se han reducido debido a malas prácticas de pastoreo. En este trabajo se analizó la variabilidad morfológica y genética de 32 poblaciones del gigante en el estado de Chihuahua, México. Nueve características morfológicas fueron evaluadas en estas poblaciones, después de dos años de trasplantadas y establecidos en un jardín de observación y bajo condiciones de temporal. La variabilidad genética se determinó utilizando los perfiles de amplificación de cuatro pares de iniciadores u oligonucleótidos. El análisis de componentes principales mostró que los tres primeros componentes explicaron el 75.3% de la variación morfológica. Los cuatro pares de iniciadores produjeron un total de 186 bandas, de las cuales el 56.45% presentó polimorfismo. La combinación de iniciadores EcoRI-AAC+MseI-CAG detectó el mayor porcentaje de polimorfismo (69.57% y 32 bandas polimórficas. El coeficiente de Dice y análisis de agrupamiento generaron cinco grupos. La variabilidad genética y morfológica encontrada en las diferentes poblaciones, podrían servir de base para la selección de ecotipos de gigante para diversos propósitos como producción de semilla, retención de suelo, restauración de ecosistemas y forraje para libre pastoreo o de corte, entre otros. Así también, los resultados de este trabajo son la base para iniciar programas de mejoramiento genético en esta especie.

  8. Ciclo biológico, comportamiento y censo del picudo del camu camu, Conotrachelus dubiae O'Brien 1995 (Coleoptera: Curculionidae en Pucallpa, Perú Biological cycle, behavior and census of camu camu weevil, Conotrachelus dubiae O'Brien 1995 (Coleoptera: Curculionidae, in Pucallpa, Peru

    Directory of Open Access Journals (Sweden)

    Diana Perez

    2008-01-01

    Full Text Available El picudo, Conotrachelus dubiae O'Brien 1995, es una de las plagas mas importantes del camu camu Myrciaria dubia H.B.K. Mc Vaugh en la Amazonía Peruana. El objetivo del presente estudio fue determinar el ciclo biológico de este insecto bajo condiciones de laboratorio y describir su comportamiento y fluctuación en condiciones de campo en Pucallpa, Ucayali, Perú. El porcentaje de eclosión de larvas fue de 87%, la duración del periodo de incubación de los huevos fue de 5,5±0,9 (4 a 7 días, del estado larval en el fruto 22,2±1,9 (20 a 25 días y en el suelo (fase pre-pupa, 54,4±5,5 (46 a 67 días, del periodo pupal 11,8±0,9 (9 a 13 días y la longevidad del adulto fue de 51,8±18,9 (9 a 75 días. Los adultos se alimentaron de frutos de diferentes diámetros y estados de maduración y de botones florales, ramas tiernas y flores. No se registró la presencia de adultos de C. dubiae en frutos secos, ni en la base del tallo, sino en ritidomas. La mayor actividad de alimentación y de reproducción de los adultos fue entre 18:30 a 22:00 h. Los adultos fueron observados en el cultivo durante todo el año, encontrándose con mayor frecuencia en los meses de enero a marzo en pisos bajos inundables y entre octubre a diciembre en tierra firme no inundable, coincidiendo con la fase de floración y fructificación de la planta.Camu camu weevil Conotrachelus dubiae O'Brien, 1995 is a one of the main pests of camu camu (Myrciaria dubia H.B.K. Mc Vaugh in Peruvian Amazonia. The aim of this study was to determine the biological cycle of this insect under laboratory conditions, to describe its behavior and population numbers under field conditions in Pucallpa, Ucayali, Peru. The percentage of hatching was 87%; the egg incubation period was 5.5±0.9 (4 to 7 days; the length of the larval stage inside the fruit was 22.2±1.9 (20 to 25 days, and the length larval stage (pre-pupa underground was 54.4±5.5 (46 to 67 days. The length of pupal period was 11.8

  9. Thermal biology of prey (Melongena corona bispinosa, Strombus pugilis, Callinectes similis, Libinia dubia) and predators (Ocyurus chrysurus, Centropomus undecimalis) of Octopus maya from the Yucatan Peninsula.

    Science.gov (United States)

    Noyola Regil, Javier; Mascaro, Maite; Díaz, Fernando; Denisse Re, Ana; Sánchez-Zamora, Adolfo; Caamal-Monsreal, Claudia; Rosas, Carlos

    2015-10-01

    On the Yucatan Peninsula there is an upwelling which allows access to a body of cold water that controls temperature in this area. This modulates the ecology and distribution of organisms that inhabit the continental shelf. The objective of this study was to determine the effect of different acclimation temperatures on the thermal biology of prey as mollusc, crustacean (Melongena corona bispinosa, Strombus pugilis, Callinectes similis, Libinia dubia) and predators as fish (Ocyurus chrysurus, Centropomus undecimalis) of Octopus maya. Octopus prey preferred temperatures between 23.5°C and 26.0°C, while predators preferred temperatures 26.4-28.5°C. The species with largest thermal windows were M. corona bispinosa (328.8°C(2)), C. similis (322.8°C(2)), L. dubia (319.2°C(2)), C. undecimalis (288.6°C(2)), O. chrysurus (237.5°C(2)), while the smallest thermal window was for S. pugilis (202.0°C(2)). The acclimation response ratios (ARR) estimated for prey ranged from 0.24-0.55 in animals exposed to CTMax and 0.21-0.65 in those exposed to CTMin. Amongst predators, ARR ranged from 0.30 to 0.60 and 0.41 to 0.53 for animals exposed to CTMax and CTMin, respectively. Correlating the optimal temperature limits of prey and predators with surface temperatures on the continental shelf and those 4m deep showed that the main prey, Callinectes similis and L. dubia, shared a thermal niche and that an increase in temperature could force these species to migrate to other sites to find optimal temperatures for their physiological functions. As a consequence the continental shelf community would undergo a structural change. Predators were found to be near their optimal temperatures in surface temperatures on the continental shelf. We conclude that they would remain in the area in a warming scenario. The size of the thermal window was related to the type of ecosystem inhabited by these species. These ARR intervals allowed us to categorize the species as temperate or tropical

  10. Conducta alimentaria de Daphnia ambigua Scourfield 1947, Moina micrura Kurz 1874 y Ceriodaphnia dubia Richard 1895 (Cladocera frente a un gradiente de concentración de alimento Feeding behaviour of Daphnia ambigua Scourfield 1947, Moina micrura Kurz 1874 and Ceriodaphnia dubia Richard 1895 (Cladocera under a food concentration gradient

    Directory of Open Access Journals (Sweden)

    GINGER MARTINEZ

    2000-03-01

    Full Text Available Debido a que Cladocera es el grupo de microfiltradores más abundante del zooplancton límnico y cuyas poblaciones se encuentran usualmente limitadas por alimento, la respuesta de los individuos frente a un gradiente de concentración de recursos tendría significativas implicancias sobre los patrones poblacionales y comunitarios. Se comparó la conducta alimentaria de Moina micrura, Ceriodaphnia dubia y Daphnia ambigua (Cladocera frente a las microalgas Chlorella sp. y Oocystis sp. (Chlorophyceae mediante los siguientes parámetros: Tasa de Ingesta Máxima (Imax, Concentración Limitante Incipiente (CLI y Eficiencia de Consumo (b, los cuales fueron obtenidos a través de un modelo de respuesta funcional. Los resultados mostraron que D. ambigua presentó las mayores Imax y CLI sobre ambos recursos, sin embargo, esta especie presentó la menor b. Mientras que D. ambigua no presentó diferencias en b sobre Chlorella sp. y Oocystis sp., M. micrura presentó una mayor b sobre Chlorella sp. y C. dubia sobre Oocystis sp. Estos resultados revelan significativas diferencias interespecíficas en la respuesta alimentaria de Cladocera, grupo que presentó un complejo comportamiento frente a variaciones en la disponibilidad de recursos alimentariosBecause Cladocera is the most abundant group of filter-feeders in the freshwater zooplankton and their populations are usually found under limited resources conditions, the individual response under a resources concentration gradient has important consequences on the population and community patterns. Feeding behavior of Moina micrura, Ceriodaphnia dubia and Daphnia ambigua (Cladocera on the microalgae Chlorella sp. and Oocystis sp. (Chlorophyceae was compared by using the following parameters: Maximum Ingestion Rate (Imax, Incipient Limiting Concentration (ILC and Consumption Efficiency (b, which were obtained through a model of functional response. Results indicated that D. ambigua showed the highest Imax and

  11. Nomina dubia in the genus Theridion resulting from errors in instalment six of Carl Wilhelm Hahn’s “Monographie der Spinnen” (Araneae: Theridiidae

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    Prpic, Nikola-Michael

    2015-11-01

    Full Text Available An overlooked error in the correlation of new scientific names with the spider images on plate 4 in Carl Wilhelm Hahn’s sixth instalment of his book ”Monographie der Spinnen” led to the notion that at least two of the spiders illustrated on plate 4 cannot be identified and their names are nomina dubia. Here, I draw attention to the fact that, if the names are re-aligned to the images in a meaningful way, then at least three spiders on plate 4 can be identified. Theridion rufipes sensu Hahn is a synonym of Gongylidium rufipes (Linnaeus, 1758 (syn. conf.. In particular, the previous nomen dubium Theridion tibiale Hahn, 1831 is a senior synonym of Lasaeola tristis (Hahn, 1833 (syn. nov.. Evidence is presented that the junior synonym is in prevailing usage and the senior synonym is therefore regarded as nomen oblitum.

  12. A comparison of the physicochemical properties and fatty acid composition of indaiá (Attalea dubia) and Babassu (Orbignya phalerata) oils.

    Science.gov (United States)

    Ferreira, Bianca Silva; Faza, Lara Pereira; Le Hyaric, Mireille

    2012-01-01

    The physicochemical properties and fatty acid composition of Attalea dubia (Mart.) Burret (indaiá) seed oil were investigated. The oil was extracted in a soxhlet apparatus using petroleum ether and evaluated for iodine, acid, peroxide, ester, and saponification values. The oil was also analyzed using infrared and nuclear magnetic resonance spectroscopy. The fatty acid profile of the oil was determined by GC-MS. For each analysis indaiá oil was compared to Orbignya phalerata (babassu) oil. The two oils appeared to be very similar in their fatty acid composition, in which lauric acid (the most abundant), myristic acid, caprylic acid, and capric acid were the four main fatty acids detected. The unsaturated fatty acids content was lower for indaiá oil (5.8%) than for babassu oil (9.4%). The results suggest that indaiá palm tree could be cultivated as a new source of vegetable oil with potential for food and cosmetic industries.

  13. The E144 residue of Scherffelia dubia centrin discriminates between the DNA repair protein XPC and the centrosomal protein Sfi1

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    Dora Grecu

    2014-01-01

    Full Text Available Centrins are members of the EF-hand family of calcium-binding proteins, which are highly conserved among eukaryotes. Centrins bind to several cellular targets, through a hydrophobic triad. However, the W1xxL4xxxL8 triad in XPC (Xeroderma Pigmentosum Group C protein is found in the reverse orientation, as in the L8xxxL4xxW1 triad in Sfi1 (Suppressor of Fermentation-Induced loss of stress resistance protein 1. As shown by previous NMR studies of human centrin 2 in complex with XPC or Sfi1, the E148 residue of human centrin 2 is in contact with XPC but is pushed away from the triad of Sfi1. We corroborated these findings using site-directed mutagenesis to generate mutations in Scherffelia dubia centrin (SdCen and by using isothermal titration calorimetry to analyze the binding affinity of these mutants to XPC and Sfi1. We mutated the F109 residue, which is the main residue involved in target binding regardless of triad orientation, and the E144 residue, which was thought to be involved only in XPC binding. The F109L mutation reduced the binding of SdCen to XPC and Sfi1 and the negative effect was greater upon temperature increase. By contrast, the E144A mutation reduced the binding to XPC but had no effect on Sfi1 binding. The F109L-E144A mutation enhanced the negative effect of the two single mutations on XPC binding. Sfi1 proteins from Ostreococcus lucimarinus and Ostreococcus tauri, which belong to the same clade as S. dubia, were also investigated. A comparative analysis shows that the triad residues are more conserved than those in human Sfi1.

  14. The E144 residue of Scherffelia dubia centrin discriminates between the DNA repair protein XPC and the centrosomal protein Sfi1.

    Science.gov (United States)

    Grecu, Dora; Blouquit, Yves; Assairi, Liliane

    2013-01-01

    Centrins are members of the EF-hand family of calcium-binding proteins, which are highly conserved among eukaryotes. Centrins bind to several cellular targets, through a hydrophobic triad. However, the W(1)xxL(4)xxxL(8) triad in XPC (Xeroderma Pigmentosum Group C protein) is found in the reverse orientation, as in the L(8)xxxL(4)xxW(1) triad in Sfi1 (Suppressor of Fermentation-Induced loss of stress resistance protein 1). As shown by previous NMR studies of human centrin 2 in complex with XPC or Sfi1, the E148 residue of human centrin 2 is in contact with XPC but is pushed away from the triad of Sfi1. We corroborated these findings using site-directed mutagenesis to generate mutations in Scherffelia dubia centrin (SdCen) and by using isothermal titration calorimetry to analyze the binding affinity of these mutants to XPC and Sfi1. We mutated the F109 residue, which is the main residue involved in target binding regardless of triad orientation, and the E144 residue, which was thought to be involved only in XPC binding. The F109L mutation reduced the binding of SdCen to XPC and Sfi1 and the negative effect was greater upon temperature increase. By contrast, the E144A mutation reduced the binding to XPC but had no effect on Sfi1 binding. The F109L-E144A mutation enhanced the negative effect of the two single mutations on XPC binding. Sfi1 proteins from Ostreococcus lucimarinus and Ostreococcus tauri, which belong to the same clade as S. dubia, were also investigated. A comparative analysis shows that the triad residues are more conserved than those in human Sfi1.

  15. The E144 residue of Scherffelia dubia centrin discriminates between the DNA repair protein XPC and the centrosomal protein Sfi1☆

    Science.gov (United States)

    Grecu, Dora; Blouquit, Yves; Assairi, Liliane

    2013-01-01

    Centrins are members of the EF-hand family of calcium-binding proteins, which are highly conserved among eukaryotes. Centrins bind to several cellular targets, through a hydrophobic triad. However, the W1xxL4xxxL8 triad in XPC (Xeroderma Pigmentosum Group C protein) is found in the reverse orientation, as in the L8xxxL4xxW1 triad in Sfi1 (Suppressor of Fermentation-Induced loss of stress resistance protein 1). As shown by previous NMR studies of human centrin 2 in complex with XPC or Sfi1, the E148 residue of human centrin 2 is in contact with XPC but is pushed away from the triad of Sfi1. We corroborated these findings using site-directed mutagenesis to generate mutations in Scherffelia dubia centrin (SdCen) and by using isothermal titration calorimetry to analyze the binding affinity of these mutants to XPC and Sfi1. We mutated the F109 residue, which is the main residue involved in target binding regardless of triad orientation, and the E144 residue, which was thought to be involved only in XPC binding. The F109L mutation reduced the binding of SdCen to XPC and Sfi1 and the negative effect was greater upon temperature increase. By contrast, the E144A mutation reduced the binding to XPC but had no effect on Sfi1 binding. The F109L-E144A mutation enhanced the negative effect of the two single mutations on XPC binding. Sfi1 proteins from Ostreococcus lucimarinus and Ostreococcus tauri, which belong to the same clade as S. dubia, were also investigated. A comparative analysis shows that the triad residues are more conserved than those in human Sfi1. PMID:24371720

  16. Remedial investigation/feasibility study of the Clinch River/Poplar Creek Operable Unit. Volume 2. Appendixes A, B, C, and D-Biota and representative concentrations of contaminants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This report presents the findings of an investigation into contamination of the Clinch River and Poplar Creek near the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation (ORR) in eastern Tennessee. For more than 50 years, various hazardous and radioactive substances have been released to the environment as a result of operations and waste management activities at the ORR. In 1989, the ORR was placed on the National Priorities List (NPL), established and maintained under the federal Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Under CERCLA, NPL sites must be investigated to determine the nature and extent of contamination at the site, assess the risk to human health and the environment posed by the site, and, if necessary, identify feasible remedial alternatives that could be used to clean the site and reduce risk. To facilitate the overall environmental restoration effort at the ORR, CERCLA activities are being implemented individually as distinct operable units (OUs). This document is Volume 2 of the combined Remedial Investigation and Feasibility Study Report for the Clinch River/Poplar Creek OU.

  17. Determinación de la tasa respiratoria de Eugenia stipitata Mc Vaugh (arazá y Myrcyaria dubia HBK (camu-camu

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    Littman Gonzáles

    2013-06-01

    Full Text Available En el presente trabajo se determinó diariamente la tasa respiratoria de Eugenia stipitata Mc Vaugh (arazá y Myrcyaria dubia HBK (camu-camu a temperaturas de 10, 20 y 28°C, utilizando un respirómetro construido en el laboratorio. Eugenia stipitata Mc Vaugh, mostró un comportamiento climatérico, debido a su elevada tasa respiratoria y la presencia de picos climatéricos que coincidieron con el inicio de la maduración sensorial. Las tasas respiratorias registradas en los picos climatéricos fueron de 91,87 mgCO2/kg.h a los 21 días de almacenamiento a 10°C, 116,82 mgCO2/kg.h a los 7 días de almacenamiento a 20°C y 125,74 mgCO2/kg.h a los 5 días de almacenamiento a 28°C, respectivamente. Fue establecido que Eugenia stipitata Mc Vaugh a bajas temperaturas presenta menores tasas de respiración, prolongando de esta manera su vida comercial a 10°C hasta 3 semanas acompañado de óptimas características organolépticas, mientras que a temperaturas más altas como 20 y 28°C la vida comercial del producto desciende a 7 y 5 días respectivamente. Del mismo modo fue estudiado Myrcyaria dubia HBK el cual mostró un comportamiento no climatérico con bajas tasas de producción de CO2 con tendencia decreciente en el tiempo y ausencia de picos climatéricos. Cuando fue sometido a una temperatura de 10°C, la tasa de respiración alcanzó 12 mgCO2/kg.h, a los 20 días. El almacenamiento a mayores temperaturas como 20 y 28°C produjo un incremento en la tasa respiratoria de más del 200% alcanzando valores de 47 y 51 mgCO2/kg.h al 10° y 7° día respectivamente.

  18. Daphnid Biomass and Activity of Free-living NAGase Under Pesticide Stresses%农药胁迫下溞类生物量与水体中NAGase活性的关系

    Institute of Scientific and Technical Information of China (English)

    郭丹丹; 李少南

    2014-01-01

    Free β-N-acetyl-D-glucosaminidase (NAGase, or chitobiase)may be an indicator of aquatic arthropod with respect to pesticide stresses. In this experiment, three species of Daphnids, i.e. Daphnia magna Straus, Moina macrocopa, and Simocephalus vetulus and three presticides, lufenuron, diafenthiuron, and etoxazole, were used to study the arthropod biomass and free-living NAGase activity. It was found that arthropod biomass(x)and NAGase activity(y)had significant correlation(y=0.000 603x﹢0.004 33, r=0.687 and P=0.00), suggesting the feasibility of using free-living NAGase activity to predict the biomass of the exposed arthropod populations. In viro studies with 10 pesticides, i.e. lufenuron, diafenthiuron, and etoxazole, butachlor, trazodone, chlorpyrifos, fenvalerate, imidacloprid, pymetrozine, and chlorantraniliprole, showed that their minimal concentrations at which the activity of free-living NAGase was directly af-fected were much higher than the highest concentrations found in water bodies. These results suggest that the biomass could be predicted without underestimation by NAGase activity.%为探索游离态 N-乙酰-β-D-氨基葡萄糖苷酶(简称 NAGase,又称壳二糖酶)作为农药对水生节肢动物胁迫效应指示因子的可行性,将大型溞、多刺裸腹溞、老年低额溞作为受试生物,虱螨脲、丁醚脲、乙螨唑作为受试药剂,研究了游离于水中的 NAGase的活性与溞类生物量之间的对应关系。以全部63个被暴露群体的生物量为自变量(x),以相应群体释放到水中的 NAGase 的活性为应变量(y),得到回归方程 y=0.000603x﹢0.00433,该方程的 r 值和 P 值分别为0.687和0.00。两者之间的对应关系证明了利用水中 NAGase 活性来预测被暴露群体生物量的可行性。进一步的研究显示,作为胁迫因子,乙螨唑在高浓度(1.6μg·L-1)下促使溞类群体萎缩,NAGase 活性下降则相对滞后。涉及10种农药

  19. A Comparison of the Physicochemical Properties and Fatty Acid Composition of Indaiá (Attalea dubia and Babassu (Orbignya phalerata Oils

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    Bianca Silva Ferreira

    2012-01-01

    Full Text Available The physicochemical properties and fatty acid composition of Attalea dubia (Mart. Burret (indaiá seed oil were investigated. The oil was extracted in a soxhlet apparatus using petroleum ether and evaluated for iodine, acid, peroxide, ester, and saponification values. The oil was also analyzed using infrared and nuclear magnetic resonance spectroscopy. The fatty acid profile of the oil was determined by GC-MS. For each analysis indaiá oil was compared to Orbignya phalerata (babassu oil. The two oils appeared to be very similar in their fatty acid composition, in which lauric acid (the most abundant, myristic acid, caprylic acid, and capric acid were the four main fatty acids detected. The unsaturated fatty acids content was lower for indaiá oil (5.8% than for babassu oil (9.4%. The results suggest that indaiá palm tree could be cultivated as a new source of vegetable oil with potential for food and cosmetic industries.

  20. Effects of Spray-Drying Parameters on In Vitro Functional Properties of Camu-Camu (Myrciaria dubia Mc. Vaugh): A Typical Amazonian Fruit.

    Science.gov (United States)

    Fujita, Alice; Souza, Volnei Brito; Daza, Luis Daniel; Fávaro-Trindade, Carmen Silvia; Granato, Daniel; Genovese, Maria Inés

    2017-03-22

    Camu-camu (Myrciaria dubia) fruit is a rich source of bioactive compounds but its shelf life is rather short. Therefore, this study was aimed to evaluate the effect of inlet air temperature (T) and concentration (C) of maltodextrin and arabic gum on the spray-drying process of commercial camu-camu pulps (São Paulo and Manaus). Moisture, solubility, total phenolics (TP), ascorbic acid (AA), and proanthocyanidins (PAC) contents, and in vitro antioxidant capacity of the powders (FRAP, DPPH, Folin-Ciocalteu's reducing capacity were measured). Arabic gum resulted in better yields (22% to 30%), powder solubility (84% to 90%), and lower losses of analyzed compounds than the powders manufactured with maltodextrin. Overall, inlet air temperature had a lower impact on the responses studied than the concentration of carrier agents. Polynomial equations were generated for AA (R(2) = 0.993), TP (R(2) = 0.735), PAC (R(2) = 0.946), and for the antioxidant capacity assays (0.867 ≤ R(2 ) ≤ 0.963). In addition, principal component analysis showed that the lowest concentration of carrier agents (6%) in spray drying resulted in the lowest losses of bioactive compounds and, consequently, the highest antioxidant capacity.

  1. Effects of diet supplementation with Camu-camu (Myrciaria dubia HBK McVaugh fruit in a rat model of diet-induced obesity

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    Ozanildo V Nascimento

    2013-03-01

    Full Text Available Amazonian Camu-camu fruit (Myrciaria dubia HBK Mc Vaugh has attracted interest from food and cosmetics industries because of its rich content of vitamin C, flavonoids and anthocyanins. The goal of this study was investigates the antiobesity action of the ingestion of the Camu-camu pulp in a rat model of diet-induced obesity. Wistar rats with obesity induced by subcutaneous injection of monosodium glutamate receiving diet ad libitum. The rats were divided in two groups: an experimental group that ingested 25 mL/day of Camu-camu pulp (CCG and a non treated group (CG. After 12 weeks, the animals were sacrificed. Blood, liver, heart, white adipose tissues were collected and weighted, biochemical and inflammatory profiles were determinate as well. Animals that received the pulp of Camu-camu reduced their weights of the fat in white adipose tissues, glucose, total cholesterol, triglycerides, LDL-c and insulin blood levels. There was an increase in HDL-c levels. No change was observed in inflammatory markers and liver enzymes. Camu-camu pulp was able to improve the biochemical profile of obesity in rats suggesting that this Amazonian fruit can be further used such a functional food ingredient in control of chronic diseases linked to obesity.

  2. 基于GTN损伤模型的压力连接过程仿真%Simulation analysis of the mechanical clinch joining process based on the GTN model

    Institute of Scientific and Technical Information of China (English)

    石柏军; 彭松; 刘松林; 王叶青

    2012-01-01

    为了准确地反映压力连接过程中材料的破坏,在仿真模型中引入了GTN损伤模型.研究了损伤模型中影响孔洞形核、成长及聚合的材料参数,模拟了压力连接过程中材料的破坏行为,并分析了连接过程材料最先断裂的位置.结果表明,GTN损伤模型可以较好地反映上板件颈部在连接过程中的断裂,并较好地判断出了连接点断裂的初始位置在上板件颈部处的内侧,更加准确地模拟了连接过程中材料的破坏过程.%The existing finite element analysis simulation methods on the mechanical clinch joining process have not considered the damage mechanism to material models.To overcome this difficulty,the GTN damage model is adopted to depict the material damage in a simulation-based theoretical model.The material parameters of the GTN model which influence the cavity nucleation,growth and closure are discussed in this work.The results show that the initial fracture point is predicted which is located at the initial side of the clinched joint neck of the upper sheet,which matches with the results of the experimental test very well.It can be concluded that the incorporation of GTN damage model has extended the capability of the simulation model.

  3. La expresión y actividad catalítica diferencial de GDP-manosa pirofosforilasa influye en la producción de vitamina C en Myrciaria dubia “camu-camu”

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    Juan Castro Gómez

    2013-12-01

    Full Text Available Myrciaria dubia muestra una amplia variación en la producción de vitamina C (vit.C. Para entender las bases moleculares de esta variación, se determinó la relación del nivel de expresión genética y actividad de GDP-Manosa pirofosforilasa (GMP con la variación del contenido de vit.C en M. dubia. Las muestras fueron obtenidas de una colección de germoplasma. La vit.C se cuantificó por HPLC, la actividad de GMP se midió por  espectrofotometría. El ARN se purificó, el ADNc se sintetizó, amplificó, clonó y secuenció con técnicas estándares. La expresión del gen se midió mediante PCR en tiempo real. Las diferencias en el contenido de vit.C de las hojas, pulpa y cáscara dependieron de la expresión y actividad de GMP. Esta relación también se observó entre plantas que producen frutos con bajo y alto contenido de vit.C. En conclusión, Las hojas, pulpa y cáscara de M. dubia muestran diferencias significativas en el contenido de vit.C, el cual se atribuye a la expresión y actividad catalítica diferencial de la GMP. Asimismo, las plantas que producen frutos con diferencias marcadas en el contenido de vit.C en sus pulpas, también dependen del nivel de expresión y actividad catalítica de esta enzima.

  4. La expresión y actividad catalítica diferencial de GDP-manosa pirofosforilasa influye en la producción de vitamina C en Myrciaria dubia “camu-camu”

    Directory of Open Access Journals (Sweden)

    Juan Castro Gómez

    2013-12-01

    Full Text Available Myrciaria dubia muestra una amplia variación en la producción de vitamina C (vit.C. Para entender las bases moleculares de esta variación, se determinó la relación del nivel de expresión genética y actividad de GDP-Manosa pirofosforilasa (GMP con la variación del contenido de vit.C en M. dubia. Las muestras fueron obtenidas de una colección de germoplasma. La vit.C se cuantificó por HPLC, la actividad de GMP se midió por espectrofotometría. El ARN se purificó, el ADNc se sintetizó, amplificó, clonó y secuenció con técnicas estándares. La expresión del gen se midió mediante PCR en tiempo real. Las diferencias en el contenido de vit.C de las hojas, pulpa y cáscara dependieron de la expresión y actividad de GMP. Esta relación también se observó entre plantas que producen frutos con bajo y alto contenido de vit.C. En conclusión, Las hojas, pulpa y cáscara de M. dubia muestran diferencias significativas en el contenido de vit.C, el cual se atribuye a la expresión y actividad catalítica diferencial de la GMP. Asimismo, las plantas que producen frutos con diferencias marcadas en el contenido de vit. C en sus pulpas, también dependen del nivel de expresión y actividad catalítica de esta enzima.

  5. Processamento, caracteriza??o f?sico-qu?mica e aceitabilidade de xaropes obtidos de frutos de cubiu (Solanun sessiliflorum Dunal) e camu camu (Myrciaria dubia McVaugh)

    OpenAIRE

    Marques, Marduce Pereira

    2006-01-01

    O cubiu (Solanum sessiliflorum Dunal) e o camu camu (Myrciaria dubia McVaugh) s?o frutos fruto nativo da Amaz?nia, com grande potencial tecn?logico em fun??o da produtividade, rendimento em polpa e valor nutritivo. Por outro lado, somando-se ao leque de caracter?sticas desej?veis tamb?m se destacam a perda do fruto in natura por falta alternativas para industrializa??o, conserva??o, agrega??o de valor e facilidades para o consumo, e, sobretudo, a necessidade de tecnologias simples. Com objeti...

  6. Semillas y plántulas de Myrciaria dubia “camu-camu”: biometría, germinación y crecimiento inicial

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    Anderson E. Medina Bardales

    2014-01-01

    Full Text Available Los objetivos planteados fueron determinar la biometría de las semillas, registrar la respiración celular en el proceso de imbibición, evaluar el efecto inductor de la germinación de compuestos químicos y analizar el crecimiento inicial. La respiración celular durante la imbibición se midió por reducción del azul de metileno y del Janus Green B. El efecto inductor de la germinación de cinco compuestos químicos fue evaluado. El crecimiento inicial se registró con estereoscopio. Los resultados mostraron que las semillas tienen en promedio un peso de 520±172 mg, largo de 13,50±1,76 mm, ancho de 10,61±1,14 mm y espesor de 4,68±0,62 mm. Estas variables mostraron correlaciones significativas (r de 0,494 a 0,897 y p 90% y 65% respectivamente. El crecimiento hasta plántula constó de seis etapas y ocurrió en un periodo de 22 días después del brote de la radícula. En conclusión, las semillas de M. dubia muestran una amplia variación en sus datos biométricos (peso, largo, ancho y espesor, pero muestran correlaciones significativas entre sí. Asimismo, las semillas son metabólicamente activas en el proceso de imbibición y su germinación es inducida por el nitrito de sodio y el cianuro de potasio. Además, el crecimiento inicial hasta plántula ocurre en un periodo de 22 días después del brote de la radícula y consta de seis etapas bien diferenciadas.

  7. Efecto citoprotector del camu-camu Myrciaria dubia en tres líneas celulares de ratón expuestos in vivo a bromato de potasio

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    Alvis Rafael

    2011-05-01

    Full Text Available Se evaluó in vivo la capacidad citoprotectora del fruto de Myrciaria dubia (Kunth McVaugh Camu-camu frente al daño mutagénico producido por bromato de potasio (68,5 mg/k sobre tres líneas celulares de ratón (hígado, riñón y células sanguíneas. Se utilizó ratones (n= 120 divididos en tres grupos los cuales bebieron ad libitum: TI= control negativo (solo agua y el grupo TIII (control positivo; El grupo TII bebió el extracto acuoso (2% p/v del fruto de camu-camu. A los diez días se inyectó una dosis única de KBr03 (68,5 mg/kg peso corporal vía intraperitoneal, a los grupos TII y TIII. El tratamiento con camu-camu continuo 35 días más, luego los ratones fueron eutanizados para determinar la frecuencia del daño al DNA mediante el protocolo del ensayo cometa alcalino. El grupo TII mostró en todas las líneas celulares el efecto citoprotector del camu-camu (p< 0,05. El efecto dañino al DNA por la acción oxidativa del KBrO3 es inhibido por el extracto acuoso del fruto de camu camu, probablemente por la presencia de los agentes antioxidantes como el Acido ascórbico y los flavonoides.

  8. Antocianinas, ácido ascórbico, polifenoles totales y actividad antioxidante, en la cáscara de camu-camu (Myrciaria dubia (H.B.K McVaugh Antocianinas, ácido ascórbico, polifenóis totais e atividade antioxidante na casca do camu-camu (Myrciaria dubia (H.B.K McVaugh

    Directory of Open Access Journals (Sweden)

    Juan Edson Villanueva-Tiburcio

    2010-05-01

    Full Text Available Este trabajo fue realizado en la UNAS, Tingo María, Perú. Los objetivos fueron evaluar el contenido de antocianinas, ácido ascórbico, y polifenoles totales, en la cáscara fresca y seca de camu-camu (Myrciaria dubia (H.B.K McVaugh en diferentes estados de madurez; evaluar la actividad antioxidante en la cáscara seca, usando diferentes tipos de radicales (DPPH, ABTS+ y Peroxilo y correlacionar el valor de ácido ascórbico y polifenoles totales con la actividad antioxidante. La extracción fue realizada en medio acuoso, y los resultados de las evaluaciones de cada experimento fueron analizados por un diseño completamente al azar (DCA, según la prueba de t-student (p A pesquisa foi realizada na UNAS em Tingo Maria, Peru, teve como objetivos: avaliar o teor de antocianinas, ácido ascórbico e polifenóis totais, na casca fresca e na casca seca do camu-camu (Myrciaria dubia (HBK McVaugh em diferentes tempos de maturação; avaliar a atividade antioxidante na casca seca utilizando diferentes tipos de radicais (DPPH, ABTS+ e Peroxilo e correlacionar o teor de ácido ascórbico e polifenóis totais com a atividade antioxidante. A extraç��o foi realizada em meio aquoso, os resultados das avaliações de cada experiência são analisados no delineamento inteiramente casualizado (DIC, pelo teste de t-student (p < 0,05. O extrato da casca da amostra madura fresca apresentou as concentrações mais elevadas de ácido ascórbico e de antocianinas em relação a meio madura e verde, com 21,95 mg.g-1 de casca e 46,42 mg.L-1 de cianidin-3-glucosídeo, respectivamente, enquanto que o extrato da casca seca meio madura apresentou o maior teor de ácido ascórbico em relação a madura e verde (53,49 mg.g-1 e de polifenóis totais: 7,70 mg Ác. Gálico/g. A maior atividade antioxidante foi encontrada no extrato da casca seca da amostra meio madura com IC50 = 46,20; 20,25 e 8,30 μg.mL-1, em comparação com DPPH radical, ABTS+ e Perox

  9. Eficacia tópica de Myrciaria dubia en la curación de quemaduras de segundo grado en ratas Holtzman.

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    Karla Pacci-Salazar

    2009-01-01

    Full Text Available Objetivo, Comparar el efecto de la crema a base de Myrciaria dubia con el efecto antibiótico de la crema de sulfadiazina argéntica. Diseño, El presente es un estudio experimental aleatorizado incompleto. Participantes, 15 ratas Holtzman hembras de 9-10 semanas a las cuales se les produjo quemaduras de segundo grado. Intervenciones, Se produjo una quemadura cuadrada de 1cm2 de piel del dorso de las ratas usando un cautín modificado para producir tres quemaduras térmicas por cada animal. Se seleccionó aleatoriamente la herida para cada tratamiento. Principales medidas de resultados, La crema a base de camu-camu se elabora con una extracción etanólica al 5% para mezclarla con Sepigel 350® a una concentración de 5%. Las heridas recibieron administración cada doce horas durante cinco días. Resultados, El promedio de la reducción de la cicatriz en el grupo camu-camu es de 69,4 ± 52,85, mientras que en el grupo sulfadiazina argéntica es de 69,26 ± 53,66. Microscópicamente se observó similar infiltración leucocitaria en la dermis y en el estrato seroso en los grupos camu-camu y sulfadiazina argéntica, y ambas fueron menores que en la del grupo control. Utilizando la prueba ANOVA, se observó que, a pesar de que la cantidad de fibroblastos en el grupo camu-camu era ligeramente mayor que en la de sulfadiazina argéntica, la diferencia no era estadísticamente significativa. Conclusiones, La presencia de epidermis en el grupo Camu-Camu, a diferencia de los demás grupos, se puede deber a una mayor de activación de células basales o a una detención de los procesos oxidativos debido a la propiedad antioxidante de este fruto.

  10. Influence of dissolved organic carbon on toxicity of copper to a unionid mussel (Villosa iris) and a cladoceran (Ceriodaphnia dubia) in acute and chronic water exposures.

    Science.gov (United States)

    Wang, Ning; Mebane, Christopher A; Kunz, James L; Ingersoll, Christopher G; Brumbaugh, William G; Santore, Robert C; Gorsuch, Joseph W; Arnold, W Ray

    2011-09-01

    Acute and chronic toxicity of copper (Cu) to a unionid mussel (Villosa iris) and a cladoceran (Ceriodaphnia dubia) were determined in water exposures at four concentrations of dissolved organic carbon (DOC; nominally 0.5, 2.5, 5, and 10 mg/L as carbon [C]). Test waters with DOC concentrations of 2.5 to 10 mg C/L were prepared by mixing a concentrate of natural organic matter (Suwannee River, GA, USA) in diluted well water (hardness 100 mg/L as CaCO(3) , pH 8.3, DOC 0.5 mg C/L). Acute median effect concentrations (EC50s) for dissolved Cu increased approximately fivefold (15-72 µg Cu/L) for mussel survival in 4-d exposures and increased about 11-fold (25-267 µg Cu/L) for cladoceran survival in 2-d exposures across DOC concentrations from 0.5 to 10 mg C/L. Similarly, chronic 20% effect concentrations (EC20s) for the mussel in 28-d exposures increased about fivefold (13-61 µg Cu/L for survival; 8.8-38 µg Cu/L for biomass), and the EC20s for the cladoceran in 7-d exposures increased approximately 17-fold (13-215 µg Cu/L) for survival or approximately fourfold (12-42 µg Cu/L) for reproduction across DOC concentrations from 0.5 to 10 mg C/L. The acute and chronic values for the mussel were less than or approximately equal to the values for the cladoceran. Predictions from the biotic ligand model (BLM) used to derive the U.S. Environmental Protection Agency's ambient water quality criteria (AWQC) for Cu explained more than 90% of the variation in the acute and chronic endpoints for the two species, with the exception of the EC20 for cladoceran reproduction (only 46% of variation explained). The BLM-normalized acute EC50s and chronic EC20s for the mussel and BLM-normalized chronic EC20s for the cladoceran in waters with DOC concentrations of 2.5 to 10 mg C/L were equal to or less than the final acute value and final chronic value in the BLM-based AWQC for Cu, respectively, indicating that the Cu AWQC might not adequately protect the mussel from acute and

  11. Fluctuación y distribución espacio-temporal de Tuthillia cognata (Hemiptera, Psyllidae y de Ocyptamus persimilis (Diptera, Syrphidae en el cultivo de camu-camu Myrciaria dubia (Myrtaceae en Ucayali, Perú Fluctuation and temporal-spatial distribution of Tuthillia cognata (Hemiptera, Psyllidae and Ocyptamus persimilis (Diptera, Syrphidae on camu-camu Myrciaria dubia (Myrtaceae in Ucayali, Peru

    Directory of Open Access Journals (Sweden)

    Diana Pérez

    2009-12-01

    Full Text Available Tuthillia cognata Hodkinson, Brown & Burckhardt, 1986 (Hemiptera, Psyllidae es una plaga importante en el cultivo de camu-camu, Myrciaria dubia H.B.K. Mc Vaugh (Myrtaceae en la Amazonía Peruana. El objetivo del presente estudio fue determinar la fluctuación y la distribución espacio-temporal de T. cognata y de su controlador biológico Ocyptamus persimilis (Curran, 1930 (Diptera, Syrphidae, entre enero a noviembre del 2004 en los caseríos San Juan y Padre Bernardo, Pucallpa, Ucayali, Perú. El número de ninfas y adultos de T. cognata fue mayor en la época lluviosa que en la seca, pero no en el número de huevos, ni en el número de colonias. Los huevos, ninfas y adultos prefirieron el tercio superior de la planta en comparación con el tercio medio e inferior en ambos caseríos. La excepción fue la presencia de huevos en el caserío San Juan que no mostró preferencias por ninguno de los tercios. No se observaron diferencias en el porcentaje de infestación por T. cognata entre ambos caseríos y entre la época seca y lluviosa. En O. persimilis, no se encontró diferencias en el número de huevos, larvas y pupas entre la época seca y lluviosa. Se observó que los huevos, larvas y pupas prefirieron el tercio superior de la planta en comparación con el tercio medio e inferior en ambos caseríos. Ambas especies, T. cognata y O. persimilis presentaron un patrón de distribución espacial - temporal agregado. Se encontró una relación directa entre el número de colonias de T. cognata y O. persimilis. Sin embargo, el número de huevos, ninfas y adultos de T. cognata no se encontraron correlacionados con el número de huevos, larvas y pupas de O. persimilis.Tuthillia cognata Hodkinson, Brown & Burckhardt, 1986 (Hemiptera, Psyllidae, is a main pest on camu-camu culture Myrciaria dubia H.B.K. Mc Vaugh (Myrtaceae in the Peruvian Amazon. The aim of the current research was to evaluate the fluctuation and spatial and temporal distribution of T

  12. 自冲铆接、无铆钉铆接与电阻点焊强度对比试验研究%Joining Strength Comparison among Self-piercing Riveting, Clinching and Resistance Spot Welding

    Institute of Scientific and Technical Information of China (English)

    黄志超; 刘晓坤; 夏令君; 占金青

    2012-01-01

    Self-piercing riveting,clinching and resistance spot welding were described by joining Q195 steel sheets and 5A05 - O aluminum sheets respectively. The tensile tests and failure modes were also analyzed. The results show that the joint of resistance spot welding have higher static strength than the other two joints when steel sheets are joined; while the joint by self-piercing riveting have the best strength when aluminum sheets are joined. The joining strength of steel sheets is a-bout 2~4 times larger than that of aluminum sheets for the same jointing technology.%采用Q195钢板和5A05-O铝板对自冲铆接、无铆钉铆接和电阻点焊3种连接工艺进行了试验,对各种连接接头进行了拉伸测试,并且分析其失效形式.试验结果表明:对于钢板与钢板的连接,电阻点焊接头静强度大于自冲铆接和无铆钉铆接接头静强度;对于铝板与铝板的连接,自冲铆接接头静强度大于电阻点焊和无铆钉铆接接头静强度.对于不同连接工艺,钢板与钢板之间的连接强度约是铝板与铝板之间的连接强度的2到4倍.

  13. Joint toxicity of ethyleneamines to algae, daphnids and fish

    Energy Technology Data Exchange (ETDEWEB)

    Wijk, R.J. van; Postma, J.F. (Akzo Research Lab., Arnhem (Netherlands). Dept. of Analytical and Environmental Chemistry); Houwelingen, H. (Akzo Research Lab., Arnhem (Netherlands). Dept. of Applied Mathematics)

    1994-01-01

    The joint toxicity of some ethyleneamines to Selenastrum capricornutum, Daphnia magna, and Poecilia reticulata have been determined as a contribution to the environmental risk assessment of wastewater discharges. A few combinations showed antagonistic or synergistic effects, but the majority of combinations were additive at the lethal level. Thus additivity appears to be a reasonable assumption for risk assessment purposes of wastewater discharges. The design of tests and the biometrical approach using models describing isobolograms to evaluate test results are described in detail. This method and subsequent statistical evaluation procedure were found to be very suitable to determine additivity in aquatic toxicity tests.

  14. Daphnid life cycle response to new generation of flame retardants

    NARCIS (Netherlands)

    Waaijers, S.L.; Bleyenberg, T.E.; Dits, A; Schoorl, M.; Schütt, J; Kools, S.A.E.; de Voogt, P.; Admiraal, W.; Parsons, J.R.; Kraak, M.H.S.

    2013-01-01

    Relatively hazardous brominated flame retardants (BFRs) are currently substituted with halogen-free flame retardants (HFFRs). Consequently, information on their persistence, bioaccumulation and toxicity (PBT) is urgently needed. Therefore, we investigated the chronic toxicity to the water flea

  15. BASEMAP, CLINCH COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — FEMA Framework Basemap datasets comprise six of the seven FGDC themes of geospatial data that are used by most GIS applications (Note: the seventh framework theme,...

  16. FLOODPLAIN, CLINCH COUNTY, GA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — he Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the...

  17. Avances de investigación para la propagación vegetativa por cultivo in vitro de Myrciaria dubia (H.B.K. Mc Vaugh “camu camu”

    Directory of Open Access Journals (Sweden)

    Sergio Pinedo Freyre

    2013-06-01

    Full Text Available El trabajo fue realizado en el Laboratorio de Cultivo de Tejidos Vegetales de la Estación Experimental Agraria San Roque, del INIA Loreto con el objetivo de establecer un protocolo para el cultivo in vitro de segmentos nodales de camu camu" Myrciaria dubia " (H.B.K Mc Vaugh. La fuente de material vegetal, fueron ramas de la parte apical de plantas adultas de la Colección Nacional de camu camu del INIA Loreto, se realizaron ensayos de desinfección, medios de cultivo y diferentes concentraciones de hormonas. El medio de cultivo utilizado fue Murashige & Skoog, MS 1962; más factores constantes 20 g/L sacarosa, 0,25 g/L carbón activado, 7 g/L agar y pH 5,7. Los tratamientos de desinfección que presentaron los mayores porcentajes (100% de supervivencia de segmentos nodales, fueron: Hipoclorito 0,3% + Chupadera 1 g/L en M&S, M&S ½ y M&S + AIB y Hipoclorito 0,5% + Chupadera 2 g/L en M&S, M&S ½ y M&S + AIB. El mejor medio de cultivo para la fase de crecimiento in vitro fue M&S + 1,5 mg/L GA3 + 10 mg/L AIA con 72% de supervivencia a los 45 días después de la siembra. El mejor medio de cultivo para la fase de multiplicación fue M&S + 2,5 mg/L BAP + 0,1 mg/L ANA con 80% de supervivencia a los 30 días después del subcultivo.

  18. Avances de investigación para la propagación vegetativa por cultivo in vitro de Myrciaria dubia (H.B.K. Mc Vaugh “camu camu”

    Directory of Open Access Journals (Sweden)

    Sergio Pinedo Freyre

    2013-06-01

    Full Text Available El trabajo fue realizado en el Laboratorio de Cultivo de Tejidos Vegetales de la Estación Experimental Agraria San Roque, del INIA Loreto con el objetivo de establecer un protocolo para el cultivo in vitro de segmentos nodales de camu camu" Myrciaria dubia " (H.B.K Mc Vaugh. La fuente de material vegetal, fueron ramas de la parte apical de plantas adultas de la Colección Nacional de camu camu del INIA Loreto, se realizaron ensayos de desinfección, medios de cultivo y diferentes concentraciones de hormonas. El medio de cultivo utilizado fue Murashige & Skoog, MS 1962; más factores constantes 20 g/L sacarosa, 0,25 g/L carbón activado, 7 g/L agar y pH 5,7. Los tratamientos de desinfección que presentaron los mayores porcentajes (100% de supervivencia de segmentos nodales, fueron: Hipoclorito 0.3%  + Chupadera 1 g/L en M&S, M&S ½ y M&S + AIB y Hipoclorito 0,5%  + Chupadera 2 g/L en M&S, M&S ½ y M&S + AIB. El mejor medio de cultivo para la fase de crecimiento in vitro fue M&S + 1,5 mg/L GA3 + 10 mg/L AIA con 72% de supervivencia a los 45 días después de la siembra. El mejor medio de cultivo para la fase de multiplicación fue M&S + 2,5 mg/L BAP + 0,1 mg/L ANA con 80% de supervivencia a los 30 días después del subcultivo.

  19. The Biological Activity of Essential Oil in Rhododendron anthopogonoides Maxim and Artemisia dubia Wall. ex Bess. to Grassland Caterpillar, Gynaephora menyuanenis (Lepidoptera: Lymantriidae)%烈香杜鹃精油和牛尾蒿精油对门源草原毛虫的生物活性

    Institute of Scientific and Technical Information of China (English)

    严林; 胡凤祖; 吴静; 韩福龙

    2009-01-01

    采用浸叶法和点滴法测定烈香杜鹃(Rhododendrom anthopogonoides Maxim)、牛尾蒿(Artemisa dubia Wall. ex Bess)植物精油对门源草原毛虫(Gynaephora menyuanensis)(鳞翅目Lepidoptera: 毒蛾科Lymantriidae )6龄幼虫的生物活性.结果表明,烈香杜鹃和牛尾蒿植物精油对幼虫具有很强的胃毒、触杀活性和拒食作用,以及生长抑制作用.烈香杜鹃精油对门源草原毛虫幼虫的生物活性高于牛尾蒿精油.

  20. Posibles factores que producen la caída de fruto de Myrciaria dubia (HBK Mc Vaugh, "camu camu" durante la fenología reproductiva de la colección "cinco cuencas" en el centro experimental San Miguel - IIAP, Loreto, Perú

    Directory of Open Access Journals (Sweden)

    Sonia Farro

    2010-01-01

    Full Text Available Se evaluaron plantas de “camu camu” en cinco cuencas de Loreto (Perú, según el porcentaje de frutos con síntomas de infestación por plagas, la retención de flores y frutos en cada una de las cuencas y diámetros de ramas, y la influencia de la precipitación y temperatura en el proceso de caída de frutos según el estado fenológico. En el factor genético, la cuenca del río Putumayo destacó por presentar mayor retención de frutos, mayor rendimiento y peso promedio de frutos, así como menor ataque por plagas. Durante el proceso fenológico que duró 12 semanas, la etapa crítica de caída de flores y frutos ocurrió durante las primeras 7, siendo la retención de flores del 5.12%. Las plagas observadas son causantes del 9.27% de la caída, siendo el 9.15% causada por Edessa sp., y 0.12% por Conotrachellus dubiae. El otro 90.73% fue originado por otros factores no determinados tales como fisiológicos, nutritivos, competencia, vientos, lluvia. Los factores ambientales de temperatura y precipitación, ejercen una influencia directa e inversamente proporcional a la caída de frutos, respectivamente.

  1. Gold Plated Lead-Clinched Lead Solder Joint Study.

    Science.gov (United States)

    1979-09-01

    NUMBERS US Army Missile Command ATTN: DRSMI- EA (R&D) Redstone Arsenal. Alabama 35809 11. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE Commander...87115 ESSO Code 9313 (ATTN: Mr. David Broude) 1 Lakehurst, New Jersey 06733 National Aeronautics and Space Administration Headquarters - Mr. D. S

  2. Acute aquatic toxicity of tire and road wear particles to alga, daphnid, and fish.

    Science.gov (United States)

    Marwood, Christopher; McAtee, Britt; Kreider, Marisa; Ogle, R Scott; Finley, Brent; Sweet, Len; Panko, Julie

    2011-11-01

    Previous studies have indicated that tire tread particles are toxic to aquatic species, but few studies have evaluated the toxicity of such particles using sediment, the likely reservoir of tire wear particles in the environment. In this study, the acute toxicity of tire and road wear particles (TRWP) was assessed in Pseudokirchneriella subcapita, Daphnia magna, and Pimephales promelas using a sediment elutriate (100, 500, 1000 or 10000 mg/l TRWP). Under standard test temperature conditions, no concentration response was observed and EC/LC(50) values were greater than 10,000 mg/l. Additional tests using D. magna were performed both with and without sediment in elutriates collected under heated conditions designed to promote the release of chemicals from the rubber matrix to understand what environmental factors may influence the toxicity of TRWP. Toxicity was only observed for elutriates generated from TRWP leached under high-temperature conditions and the lowest EC/LC(50) value was 5,000 mg/l. In an effort to identify potential toxic chemical constituent(s) in the heated leachates, toxicity identification evaluation (TIE) studies and chemical analysis of the leachate were conducted. The TIE coupled with chemical analysis (liquid chromatography/mass spectrometry/mass spectrometry [LC/MS/MS] and inductively coupled plasma/mass spectrometry [ICP/MS]) of the leachate identified zinc and aniline as candidate toxicants. However, based on the high EC/LC(50) values and the limited conditions under which toxicity was observed, TRWP should be considered a low risk to aquatic ecosystems under acute exposure scenarios.

  3. Effect of Total Organic Acid of Thladiantha dubia on Active Capacity of Isolated Rat Uterine Smooth Muscle in vitro%赤雹果总有机酸对大鼠离体子宫平滑肌的作用及机制研究

    Institute of Scientific and Technical Information of China (English)

    赵盼; 佟继铭; 刘玉玲; 宋素英

    2013-01-01

    Objective: To explore the effects of the total organic acid of Thladiantha dubia (FTDBP) on activity of isolated rat uterus smooth muscle in vitro. Method: The effect of the FTDBP on activity of the isolated rat uterus smooth muscle of non-pregnant rats eight weeks old was recorded by Maclab/4e four channels physiological recorder. Four antagonists, propranolol hydrochloride tablets (3.4 × 10-7 mol · L-1 ), diphenhydramine hydrochloride tablets (2 × 10 mol ·L-1 ) , ranitidine hydrochloride tablets (2 × 10 mol · L-1 ) and atropine sulfate tablets (2 × 10 mol·L-1 ) were used to study their mechanism respectively. Result: Compare with model group, the FTDBP markedly inhibited the tension, frequency and activity of uterus of rat in vitro. And the IC50 of FTDBP was 0. 100 24 g·L-1. Conclusion: The effect of FTDBP on activity of uterine smooth muscle in rats is mainly associated with M receptor but not H1 receptor, H2 receptor or β receptor.%目的:观察赤雹果总有机酸(FTDBP)对大鼠离体子宫平滑肌活力的影响.方法:选用8周龄Wistar雌性未孕大鼠,以子宫平滑肌的收缩频率、收缩幅度指标,计算子宫平滑肌活力及FTDBP的半数抑制浓度(IC50).以盐酸普萘洛尔、盐酸苯海拉明、盐酸雷尼替丁、硫酸阿托品为阻断剂,观察FTDBP对子宫平滑肌作用与β,H1,H2,M受体的关系,探讨FTDBP对子宫平滑肌的作用机制.结果:与模型组比较,FTDBP剂量组(0.032,0.064,0.128 g·L-1)和元胡止痛片组对缩宫素所致大鼠离体子宫平滑肌的收缩频率、收缩幅度和活力均有明显的抑制作用(P<0.05或P<0.01),IC50为0.100 24 g·L-1;与模型组比较,硫酸阿托品组大鼠子宫平滑肌的收缩频率、幅度和活力差异无统计学意义.结论:FTDBP对大鼠子宫平滑肌活力有明显的抑制作用,其作用是通过抑制M受体实现的,与H1,H2,β受体无关.

  4. ENANTIOSELECTIVE CHRONIC TOXICITY OF FIPRONIL TO CERIODAPHNIA DUBIA

    Science.gov (United States)

    Fipronil is a phenylpyrazole pesticide that has greatly increased in popularity in recent years. As a chiral molecule, fipronil is released into the environment as a 1:1 mixture (called a racemate) of its two enantiomers. Previous toxicity work has indicated that the enantiomer...

  5. 赤雹果总有机酸对寒凝血瘀模型大鼠凝血时间及血液流变学的影响Δ%Effects of Total Organic Acid of Thladiantha dubia Fruit on Coagulation Time and Hemorheology of Rats with Cold Coagulation and Blood Stasis

    Institute of Scientific and Technical Information of China (English)

    刘建东; 李莹; 马帅; 佟继铭

    2016-01-01

    目的:观察赤雹果总有机酸对寒凝血瘀模型大鼠凝血时间及血液流变学的影响。方法:将60只大鼠随机分为正常对照组(水)、模型对照组(水)、阿司匹林组(阳性药物,50 mg/kg)和赤雹果总有机酸低、中、高剂量组(50、100、200 mg/kg),每组10只。除正常对照组外,其余各组大鼠均采用4℃冰水浴冷刺激+ih肾上腺素复制寒凝血瘀模型,并同时ig相应药物,每天1次,连续14 d。末次给药24 h后,腹主动脉取血,测定凝血时间、血细胞比容、血浆黏度、凝血酶原时间、凝血酶时间、活化部分凝血酶时间、血小板聚集率及全血低、中、高切黏度,并计算血沉方程K值。结果:与正常对照组比较,模型对照组凝血时间、凝血酶原时间、凝血酶时间、活化部分凝血酶时间缩短,血细胞比容、血浆黏度、血沉方程K值、血小板聚集率及全血低、中、高切黏度升高(P<0.05或P<0.01)。与模型对照组比较,阿司匹林组和赤雹果总有机酸中、高剂量组凝血时间、凝血酶时间及活化部分凝血酶时间延长,血小板聚集率降低;各给药组凝血酶原时间延长,血细胞比容、血浆黏度、血沉方程K值及全血低、中切黏度降低(P<0.05或P<0.01)。结论:赤雹果总有机酸对寒凝血瘀模型大鼠有明显的抗凝和改善血液流变学的作用。%OBJECTIVE:To observe the effects of total organic acid of Thladiantha dubia fruit(TOATF)on coagulation time and hemorheology of rats with cold coagulation and blood stasis. METHODS:60 rats were randomly divided in normal control group (water),model control group (water),aspirin group (positive drug,50 mg/kg) and TOATF low-dose,medium-dose and high-dose groups(50,100,200 mg/kg)with 10 rats in each group. Except for normal control group,cold coagulation and blood stasis model was induced by 4 ℃ water bath and subcutaneous

  6. Outlet plenum flow stratification studies for the Clinch River Breeder Reactor Plant

    Energy Technology Data Exchange (ETDEWEB)

    Novendstern, E.H.; Woods, M.D.; Andreychek, T.S.; Flannigan, L.J.; Carr, J.A.

    1976-01-01

    The transient temperature behavior during a simulated reactor trip was studied in a 1/3 sector, 0.55 scale model of the reactor outlet plenum of the CRBRP. Buoyancy effects were simulated using water and salt solution. Effects of variations in Richardson Number (ratio of buoyancy/inertia forces) and Froude Number (ratio of inertia/viscous forces) were evaluated. Effects of geometrical changes of a component in the outlet plenum called the Upper Internals Structure on transient temperature response were studied; both height of the structure and leakage under this component were experimentally varied. The test results confirm that flow stratification occurs in the outlet plenum following a reactor trip. The colder, denser fluid issuing from the core assemblies during the transient fills the lower portion of the plenum while the hotter fluid is trapped in the region above the outlet nozzles.

  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CLINCH COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  8. Chronic intestinal pseudo-obstruction: systematic histopathological approach can clinch vital clues.

    Science.gov (United States)

    Mallick, Saumyaranjan; Prasenjit, Das; Prateek, Kinra; Shasanka, Panda S; Virender, Sekhon; Rajni, Yadav; Gaurav, Jindal; Vijay, Maneesh K; Arun, Kumar V; Mahajan, J K; Sandeep, Agarwala; Ranjan, Dash Nihar; Siddhartha, Datta Gupta

    2014-05-01

    The histopathological approach of chronic intestinal pseudo-obstruction (CIP) is critical, and the findings are often missed by the histopathologists for lack of awareness and nonavailability of standard criteria. We aimed to describe a detailed histopathological approach for working-up cases of CIP by citing our experience. Eight suspected cases of CIP were included in the study to determine and describe an approach for reaching the histopathological diagnosis collected over a period of the last 1.5 years. The Hirschsprung's disease was put apart from the scope of this study. A detailed light microscopic analysis was performed along with special and immunohistochemical stains. Transmission electron microscopy was carried out on tissue retrieved from paraffin embedded tissue blocks. Among the eight cases, three were neonates, one in the pediatric age group, two adolescent, and two adults. After following the described critical approach, we achieved the histological diagnoses in all the cases. The causes of CIP noted were primary intestinal neuronal dysplasia (IND) type B (in 4), mesenchymopathy (in 2), lymphocytic myenteric ganglionitis (in 1), and duplication of myenteric plexus with leiomyopathy (in 1). Desmosis was noted in all of them along with other primary pathologies. One of the IND patients also had visceral myopathy, type IV. Histopathologists need to follow a systematic approach comprising of diligent histological examination and use of immunohistochemistry, immunocytochemistry, and electron microscopy in CIP workup. Therapy and prognosis vary depending on lesions identified by pathologists. These lesions can be seen in isolation or in combinations.

  9. Vascular Plant Species Occurrences - Okefenokee National Wildlife Refuge, Charlton, Clinch, and Ware Counties GA

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This spreadsheet contains up-to-date (2016) information on the occurrence of vascular plant species observed within the Okefenokee NWR since 1932. This list should...

  10. Ecological impacts of lead mining on Ozark streams: toxicity of sediment and pore water.

    Science.gov (United States)

    Besser, John M; Brumbaugh, William G; Allert, Ann L; Poulton, Barry C; Schmitt, Christopher J; Ingersoll, Christopher G

    2009-02-01

    We studied the toxicity of sediments downstream of lead-zinc mining areas in southeast Missouri, using chronic sediment toxicity tests with the amphipod, Hyalella azteca, and pore-water toxicity tests with the daphnid, Ceriodaphnia dubia. Tests conducted in 2002 documented reduced survival of amphipods in stream sediments collected near mining areas and reduced survival and reproduction of daphnids in most pore waters tested. Additional amphipod tests conducted in 2004 documented significant toxic effects of sediments from three streams downstream of mining areas: Strother Creek, West Fork Black River, and Bee Fork. Greatest toxicity occurred in sediments from a 6-km reach of upper Strother Creek, but significant toxic effects occurred in sediments collected at least 14 km downstream of mining in all three watersheds. Toxic effects were significantly correlated with metal concentrations (nickel, zinc, cadmium, and lead) in sediments and pore waters and were generally consistent with predictions of metal toxicity risks based on sediment quality guidelines, although ammonia and manganese may also have contributed to toxicity at a few sites. Responses of amphipods in sediment toxicity tests were significantly correlated with characteristics of benthic invertebrate communities in study streams. These results indicate that toxicity of metals associated with sediments contributes to adverse ecological effects in streams draining the Viburnum Trend mining district.

  11. Evaluation of the effect of water type on the toxicity of nitrate to aquatic organisms.

    Science.gov (United States)

    Baker, Josh A; Gilron, Guy; Chalmers, Ben A; Elphick, James R

    2017-02-01

    A suite of acute and chronic toxicity tests were conducted to evaluate the sensitivity of freshwater organisms to nitrate (as sodium nitrate). Acute exposures with rainbow trout (Onchorhynchus mykiss) and amphipods (Hyalella azteca), as well as chronic exposures with H. azteca (14-d survival and growth), midges (Chironomus dilutus; 10-d survival and growth), daphnids (Ceriodaphnia dubia; 7-d survival and reproduction), and fathead minnows (Pimephales promelas; 7-d survival and growth) were used to determine sublethal and lethal effect concentrations. Modification of nitrate toxicity was investigated across a range of ionic strengths, created through the use of very soft water, and standard preparations of synthetic soft, moderately-hard and hard dilution waters. The most sensitive species tested were C. dubia and H. azteca, in soft water, with reproduction and growth IC25 values of 13.8 and 12.2 mg/L NO3-N, respectively. All of the organisms exposed to nitrate demonstrated significantly reduced effects with increasing ionic strength associated with changes in water type. Possible mechanisms responsible for the modifying effect of increasing major ion concentrations on nitrate toxicity are discussed.

  12. Neuropeptide und die Regulation des Kohlenhydratstoffwechsels im Fettkörper der Argentinischen Schabe (Blaptica dubia)

    OpenAIRE

    Liewald, Jana F.

    2002-01-01

    Trehalose ist der Hauptblutzucker in der Hämolymphe der meisten Insekten. Trehalose wird im Fettkörper synthetisiert, dem wichtigsten Organ des Intermediärstoffwechsels bei Insekten. Wie die Homöostase des Blutzuckers reguliert wird, ist nicht vollständig geklärt. Die Produktion von Trehalose erfordert eine grundlegende Umschaltung im Stoffwechsel des Fettkörpers, die mehrere wichtige Stoffwechselwege betrifft, so dass die Fettkörperzellen (Trophocyten) von der Speicherung und Katabolisierung...

  13. The acute toxicity of major ion salts to Ceriodaphnia dubia: I. Influence of background water chemistry

    Science.gov (United States)

    The ions Na+, K+, Ca2+, Mg2+, Cl-, SO42-, and HCO3-/CO32- (referred to as “major ions”) are present in all fresh waters and are physiologically required by aquatic organisms, but can be increased to harmful levels by a variety of anthropogenic activities that speed ge...

  14. The Acute Toxicity of Major Ion Salts to Ceriodaphnia dubia: I. Influence of background water chemistry.

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset provides concentration-response data and associated general chemistry conditions for 26 experiments consisting of 149 tests regarding the acute toxicity...

  15. Evaluation of Invertebrate Bioaccumulation of Fly Ash Contaminants in the Emory, Clinch, and Tennessee Rivers, 2009 - 2010

    Energy Technology Data Exchange (ETDEWEB)

    Smith, John G [ORNL

    2012-05-01

    This report provides a summary of results from studies on invertebrate bioaccumulation of potential contaminants associated with a major fly ash spill into the Emory River following the failure of a dike at the Tennessee Valley Authority's (TVA) Kingston Fossil Plant (KIF) in Kingston, Tennessee, in late December 2008. Data included in this report cover samples collected in calendar years 2009 and 2010. Samples collected from most sites in 2009 were processed by two different laboratories using different approved U.S. Environmental Protection Agency (EPA) analytical methods: ALS Laboratory Group in Ft. Collins, CO, processed sampling using EPA method 6010 (but method 6020 for uranium and SW7470 for mercury), and PACE Analytical in Minneapolis, MN, used EPA method 6020. A preliminary evaluation of results from both laboratories indicated that some differences exited in measured concentrations of several elements, either because of specific differences of the two methods or inter-laboratory differences. While concentration differences between the laboratories were noted for many elements, spatial trends depicted from the results of both methods appeared to be similar. However, because samples collected in the future will be analyzed by Method 6020, only the results from PACE were included in this report to reduce data variation potentially associated with inter-laboratory and analytical method differences.

  16. The Acute Toxicity of Major Ion Salts to Ceriodaphnica dubia. II. Empirical Relationships in Binary Salt Mixtures

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset provides concentration-response data and associated general chemistry conditions for 29 experiments consisting of 209 tests regarding the acute toxicity...

  17. Camu-camu (Myrciaria dubia: Fruta tropical de excelentes propiedades funcionales que ayudan a mejorar la calidad de vida

    Directory of Open Access Journals (Sweden)

    Ericka Arellano-Acuña

    2016-01-01

    Full Text Available El camu-camu, es la fruta que posee el mayor contenido de vitamina C, el cual es 100 veces mayor al limón. Esta fruta tropical es nativa de la región amazónica y se encuentra principalmente distribuida en Bolivia, Brasil, Colombia, Ecuador, Perú y Venezuela. En su composición, presenta diversos compuestos bioactivos como carotenoides, antioxidantes, vitaminasy compuestos fenólicos como antocianinas y taninos, que le confieren las características de un alimento funcional. Asimismo, tiene propiedades benéficas en la salud de quienes lo consumen, ya que es considerado un poderoso antioxidante, antiinflamatorio y antimicrobial; también es un gran aliado contra enfermedades cardiovasculares y para personas que sufren de obesidad. Investigaciones demuestran su efecto positivo para el tratamiento de las etapas iniciales de la diabetes, además de ofrecer otros beneficios. Este trabajo de revisión tuvo como objetivo el estudio de la literatura respecto al Camu-camu como alimento funcional que contribuye a mejorar la calidad de vida debido a su impacto positivo en la salud.

  18. EVALUATING THE ROLE OF ION COMPOSITION ON THE TOXICITY OF COPPER TO CERIODAPHNIA DUBIA IN VERY HARD WATERS

    Science.gov (United States)

    The mitigating effect of increasing hardness on metal toxicity is reflected in water quality criteria in the United States. - - - Copper toxicity did not consistently vary as a function of hardness, but likely as a function of other water quality characteristics (e.g. alkalinity ...

  19. Comparative sensitivity of centroptilum triangulifer, ceriodaphnia dubia and daphnia magna to standard salt and copper reference toxicants

    Science.gov (United States)

    Development of methods for assessing exposure and effects of produced waters from energy and mineral resource extraction operations on stream invertebrate species is important in order to elucidate environmentally relevant information. Centroptilum triangulifer is a parthenogene...

  20. Fourth report on the Oak Ridge National Laboratory Biological Monitoring and Abatement Program for White Oak Creek Watershed and the Clinch River

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M. [ed.

    1994-04-01

    In response to a condition of the National Pollutant Discharge Elimination System (NPDES) permit issued to Oak Ridge National Laboratory (ORNL) on April 1, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for White Oak Creek (WOC) and selected tributaries. BMAP currently consists of six major tasks that address both radiological and nonradiological contaminants in the aquatic and terrestrial environs on-site and the aquatic environs off-site. These tasks are (1) toxicity monitoring, (2) bioaccumulation monitoring of nonradiological contaminants in aquatic biota, (3) biological indicator studies, (4) instream ecological monitoring, (5) assessment of contaminants in the terrestrial environment, and (6) radioecology of WOC and White Oak Lake. The ecological characterization of the WOC watershed will provide baseline data that can be used to document the ecological effects of the water pollution control program and the remedial action program. The long-term nature of BMAP ensures that the effectiveness of remedial measures will be properly evaluated.

  1. 无铆和自冲铆在汽车行业中的应用%Application research on clinching and self-piercing riveting in automotive industry

    Institute of Scientific and Technical Information of China (English)

    贡泽飞; 焦孟旺; 卢晓薇; 王刚; 李贺; 杨洁

    2014-01-01

    采用不同厚度板材对自冲铆铆接和无铆钉铆接进行两种连接方法试验.通过拉伸试验测定接头抗剪强度,并结合接头失效形式、接头剖面形貌对铆接接头进行综合评价分析.结果表明:板材越厚,无铆和自冲铆接头失效过程中需要吸收更多能量,因而有更高的连接刚度和抗剪强度;无铆接头常见失效形式为上下板材拉脱失效;自冲铆接头常见失效形式为板材撕裂失效和铆钉腿部拉脱失效.

  2. Quality assurance/quality control summary report on phase 2 of the Clinch River remedial investigation at the Oak Ridge Reservation, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Holladay, S.K.; Anderson, H.M.; Benson, S.B.; Bevelhimer, M.S.; Brandt, C.C.; Chavannes, C.M.; Cook, R.B.; Evans, D.A.; Ford, C.J.; Harris, R.A.; Horwedel, B.M.; Jackson, B.L.

    1996-12-01

    Quality assurance (QA) objectives for Phase 2 were that (1) scientific data generated would withstand scientific and legal scrutiny; (2) data would be gathered using appropriate procedures for sample collection, sample handling and security, chain of custody, laboratory analyses, and data reporting; (3) data would be of known precision and accuracy; and (4) data would meet data quality objectives defined in the Phase 2 Sampling and Analysis Plan. A review of the QA systems and quality control (QC) data associated with the Phase 2 investigation is presented to evaluate whether the data were of sufficient quality to satisfy Phase 2 objectives. The data quality indicators of precision, accuracy, representativeness, comparability, completeness, and sensitivity were evaluated to determine any limitations associated with the data. Data were flagged with qualifiers that were associated with appropriate reason codes and documentation relating the qualifiers to the reviewer of the data. These qualifiers were then consolidated into an overall final qualifier to represent the quality of the data to the end user. In summary, reproducible, precise, and accurate measurements consistent with CRRI objectives and the limitations of the sampling and analytical procedures used were obtained for the data collected in support of the Phase 2 Remedial Investigation.

  3. Designing ‘Inside the Box' with Clinch Hardware%在机壳设计中应用自扣紧固件

    Institute of Scientific and Technical Information of China (English)

    Skip Ross

    2003-01-01

    对设计工程师来说,为了遵循DFMA(面向制造与装配的设计)和DFS(面向维护的设计)原圳,选择有效的紧固或接台方法并不能仪仅恨据个人喜好进行。紧固和接台方法必顶能够提高装配效率、保旺最终产品完整性,并允许在需要的时候对部件进行操怍。对于机壳来说,由于不同部件的空间限制,

  4. Uptake, retention and internalization of quantum dots in Daphnia is influenced by particle surface functionalization

    Energy Technology Data Exchange (ETDEWEB)

    Feswick, A., E-mail: afeswick@yahoo.ca [Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States); Canadian Rivers Institute, University of New Brunswick, PO Box 5050, Saint John NB, CA (United States); Griffitt, R.J., E-mail: joe.griffitt@usm.edu [Department of Coastal Sciences, University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564 (United States); Siebein, K., E-mail: kerry.siebein@nist.gov [Major Analytical Instrumentation Center, University of Florida, PO Box 116400, Gainesville, FL 32611 (United States); Barber, D.S., E-mail: barberd@vetmed.ufl.edu [Center for Environmental and Human Toxicology, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States)

    2013-04-15

    Highlights: ► Daphnia underwent a waterborne exposure of PEG, NH{sub 2} and COOH functionalized quantum dot nanoparticles. ► There was preferential retention of COOH nanoparticles. ► TEM demonstrated that NH{sub 2} and COOH nanoparticles were internalized in cells adjacent to the GI tract. ► This cellular internalization was confirmed using energy dispersive spectroscopy. -- Abstract: Nanomaterials are a diverse group of compounds whose inevitable release into the environment warrants study of the fundamental processes that govern the ingestion, uptake and accumulation in aquatic organisms. Nanomaterials have the ability to transfer to higher trophic levels in aquatic ecosystems, and recent evidence suggests that the surface chemistry of both the nanoparticle and biological membrane can influence uptake kinetics. Therefore, our study investigates the effect of surface functionalization on uptake, internalization and depuration in Daphnia spp. Uncharged (polyethylene glycol; PEG), positively charged (amino-terminated: NH{sub 2}) and negatively charged (carboxyl-modified; COOH) cadmium selenide/zinc sulfide quantum dots were used to monitor ingestion, uptake and depuration of nanometals in Daphnia magna and Ceriodaphnia dubia over 24 h of exposure. These studies demonstrated that particles with higher negative charge (COOH quantum dots) were taken up to a greater extent by Daphnia (259.17 ± 17.70 RFU/20 Daphnia) than either the NH{sub 2} (150.01 ± 18.91) or PEG quantum dots (95.17 ± 9.78), however this is likely related to the functional groups attached to the nanoparticles as there were no real differences in zeta potential. Whole body fluorescence associates well with fluorescent microscopic images obtained at the 24 h timepoint. Confocal and electron microscopic analysis clearly demonstrated that all three types of quantum dots could cross the intestinal epithelial barrier and be translocated to other cells. Upon cessation of exposure, elimination of

  5. Differences in orientation behaviour underlie interclonal differences in phototaxis in Daphnia magna

    NARCIS (Netherlands)

    Van Gool, E.

    1999-01-01

    I studied the orientation direction of the body and the eye in response to contrasts in Daphnia magna. The orientation of the body was studied on pinned, but freely rotating daphnids, and on freely swimming daphnids. The orientation direction of the eye was studied on daphnids with a fixed position

  6. Effect of location and diameter of the branch in three genotypes of Myrciaria dubia (HBK "camu camu" for vegetative propagation by air layering

    Directory of Open Access Journals (Sweden)

    Jiang Oliver Liao Torres

    2012-09-01

    Full Text Available The objective of this study was to evaluate the effect of the location and diameter of the branch in three genotypes of camu camu using the technique of air layering on rooting and sprouting. The mother plants were bent and then rooted branches were transplanted following the design of randomized complete block with three replications. At 3 months after transplantation was the assessment of the variables, finding the best values for the number of roots to the middle third, thick diameter, Genotype MD-015 and the upper, thick diameter, Genotype MD-015 with 28.67 and 28.33 roots, respectively, in the variable length of the upper third roots, thick diameter, Genotype MD-015 showed the best results with 15.27 cm. Regarding the number of outbreaks upper, thick diameter, Genotype MD-014 and the upper, thick diameter, Genotype MD-015 achieved the best results with 13.00 and 12.67 outbreaks, respectively, in the length of shoots, the best treatment was the upper, thick diameter, Genotype MD-015 with 30.73 cm, and finally in the variable number of leaves / shoot highlights the upper, thick diameter, Genotype MD-014 and the upper, thick diameter, Genotype MD-015 with 15.10 leaves per shoot and 14.83, respectively. The results allowed identifying the upper, thick diameter, Genotype MD-015 as the best in terms of rooting and sprouting capacity.

  7. Fertirriego en la producción del camu camu (Myrciaria dubia HBK Mc Vaugh en la estación experimental del IIAP, Ucayali, Perú

    Directory of Open Access Journals (Sweden)

    Carlos Abanto

    2011-01-01

    Full Text Available El trabajo se desarrolló en la parcela Y1 del Instituto de Investigaciones de la Amazonía Peruana - IIAP Ucayali; ubicado en tre las coordenadas 8º 22’ 31’’ de latitud Sur y 74º 34’ 35’’ de longitud Oeste a una altitud de 154 m.s.n.m. Posee un suelo ultisols con fertilidad baja (Materia orgánica 1.4%, fósforo 0.4ppm, potasio 25ppm, pH de 4.58, alto contenido de aluminio 6 meq/1 00 g y CIC de 6.72 meq/100 g de suelo. El objetivo fue determinar el comportamiento fenológico y rendimiento de fruto de las plantas francas de camu camu de 7 años de edad procedentes de una mezcla de semillas, aplicando 5 tratamientos mediante la técn ica del fertirriego mediante un sistema de riego por goteo (RG. Se utilizó un Diseño de Bloques Completamente al Azar (DBCA con 3 repeticiones, 5 tratamientos y 15 unidades experimentales con 15 plantas cada una; los tratamientos fueron T0 [Sin riego y s in fertilización], T1 [Riego por goteo sin fertilización], T2 [60 - 40 - 80/N - P - K mas RG], T3 [120 - 80 - 160/N - P - K mas RG], T4 [240 - 160 - 320/N - P - K mas RG]. Para uniformizar el material se realizó podas de fructificación y defoliación manual. Se evaluó la fenología reproductiva, Nº de botones florales, Nº de frutos pequeños, Nº de frutos de cosecha, peso de fruto en g y rendimiento en t.ha - 1 . Se logró uniformizar las etapas fenológicas desde la emisión de brotes hasta la cosecha concluyendo el ciclo productivo en 205 días. Los resultados obtenidos muestran que no existen diferencias estadísticas significativas. Finalmente se determinó que el T2 obtuvo 4.8 t.ha - 1 duplicando al T0 con lo cual resultó más rentable que los demás tratamientos.

  8. Part 2: Sensitivity comparisons of the insect Centroptilum triangulifer to Ceriodaphnia dubia and Daphnia magna using standard reference toxicants; NaCl, KCl and CuSO4

    Science.gov (United States)

    Criteria for establishing water quality standards that are protective of all native biota are generally based upon laboratory toxicity tests. These test utilize common model organisms that have established test methods. However, only a small portion of species have established ...

  9. Fertirriego en la producción del camu camu (Myrciaria dubia HBK Mc Vaugh) en la estación experimental del IIAP, Ucayali, Perú,

    OpenAIRE

    2012-01-01

    El trabajo se desarrolló en la parcela Y1 del Instituto de Investigaciones de la Amazonía Peruana - IIAP Ucayali; ubicado en tre las coordenadas 8º 22’ 31’’ de latitud Sur y 74º 34’ 35’’ de longitud Oeste a una altitud de 154 m.s.n.m. Posee un suelo ultisols con fertilidad baja (Materia orgánica 1.4%, fósforo 0.4ppm, potasio 25ppm, pH de 4.58, alto contenido de aluminio 6 meq/1 00 g y CIC de 6.72 meq/100 g de suelo). El objetivo fue determinar el comportamiento fenológico y rendimiento de fru...

  10. Part 2: Sensitivity comparisons of the insect Centroptilum triangulifer to Ceriodaphnia dubia and Daphnia magna using standard reference toxicants; NaCl, KCl and CuSO4

    Science.gov (United States)

    Criteria for establishing water quality standards that are protective of all native biota are generally based upon laboratory toxicity tests. These test utilize common model organisms that have established test methods. However, only a small portion of species have established ...

  11. Development of acute toxicity quantitative structure activity relationships (QSAR) and their use in linear alkylbenzene sulfonate species sensitivity distributions.

    Science.gov (United States)

    Belanger, Scott E; Brill, Jessica L; Rawlings, Jane M; Price, Brad B

    2016-07-01

    Linear Alkylbenzene Sulfonate (LAS) is high tonnage and widely dispersed anionic surfactant used by the consumer products sector. A range of homologous structures are used in laundry applications that differ primarily on the length of the hydrophobic alkyl chain. This research summarizes the development of a set of acute toxicity QSARs (Quantitative Structure Activity Relationships) for fathead minnows (Pimephales promelas) and daphnids (Daphnia magna, Ceriodaphnia dubia) using accepted test guideline approaches. A series of studies on pure chain length LAS from C10 to C14 were used to develop the QSARs and the robustness of the QSARs was tested by evaluation of two technical mixtures of differing compositions. All QSARs were high quality (R(2) were 0.965-0.997, p < 0.0001). Toxicity normalization employing QSARs is used to interpret a broader array of tests on LAS chain length materials to a diverse group of test organisms with the objective of developing Species Sensitivity Distributions (SSDs) for various chain lengths of interest. Mixtures include environmental distributions measured from exposure monitoring surveys of wastewater effluents, various commercial mixtures, or specific chain lengths. SSD 5th percentile hazardous concentrations (HC5s) ranged from 0.129 to 0.254 mg/L for wastewater effluents containing an average of 11.26-12 alkyl carbons. The SSDs are considered highly robust given the breadth of species (n = 19), use of most sensitive endpoints from true chronic studies and the quality of the underlying statistical properties of the SSD itself. The data continue to indicate a low hazard to the environment relative to expected environmental concentrations.

  12. Toxicity of major geochemical ions to freshwater species

    Science.gov (United States)

    Extensive testing regarding the toxicity of major geochemical ions to Ceriodaphnia dubia, Hyalella azteca, and Pimephales promelas will be presented. For C. dubia, tests of single salts and binary mixtures in various dilution waters demonstrated multiple mechanisms of toxicity an...

  13. Determinação da formulação e caracterização do néctar de camu-camu (Myrciaria dubia McVaugh Formulation determination and characterisation of the camu-camu (Myrciaria dubia McVaugh nectar

    Directory of Open Access Journals (Sweden)

    Roberto N. Maeda

    2006-03-01

    Full Text Available O camu-camu é um fruto silvestre, encontrado nas margens de rios e lagos da Amazônia, com grande potencial econômico pelas suas características agronômicas, tecnológicas e nutricionais. Entretanto, seu consumo ainda é restrito, devido à alta acidez, amargor e adstringência da casca, necessitando, dessa forma, de tecnologias adequadas para o seu uso. O presente estudo teve por objetivo determinar a formulação ideal do néctar de camu-camu e avaliar as suas caraterísticas físicas e físico-químicas. Para a obtenção do néctar, foram elaboradas nove formulações com diferentes concentrações de polpa e açúcar, as quais foram submetidas ao teste de preferência de 30 provadores não treinados. Dentre as formulações testadas, a de maior preferência foi a preparada com 17,5% de açúcar e 17% de polpa, a qual apresentou valor de L Hunter de 32,00, aHunter de 3,22 e bHunter de -0,38, ácido ascórbico de 382,07 mg/100 mL, antocianinas de 2,51 mg/100 g e aceitabilidade global de 89,1%. Os resultados demonstram a viabilidade tecnológica e nutricional do néctar de camu-camu por ser um produto atraente de cor, sabor, aroma, aceitabilidade e como fonte de Vitamina C.Camu-camu is a wild fruit distributed throughout the banks of lakes and rivers in Amazonia, which presents a great economical potential on account of its agronomic, technological and nutritional features. Nevertheless, its consumption is still restricted due to its high acidity, bitterness, and skin astringency, thus needing the use of proper technologies for its use. The objective of the present study was to determine the ideal camu-camu nectar formulation and to assess its physical and physical-chemical characteristics. Nine formulations with different pulp and sugar concentrations, which were submitted to a preference test by a board of 30 untrained tasters, were prepared in order to obtain the nectar. Among the tested formulations, the one presenting the highest degree of preference was prepared with 17.5% of sugar and 17% of pulp, presenting values of L Hunter 32.00, aHunter 3.22 and bHunter -0.38, ascorbic acid 382.07 mg/100 mL, anthocyanins 2.51 mg/100 g and 89.1% global acceptance. The findings demonstrate the camu-camu nectar's nutritional and technological viability on account of its attractive colour, good tasting flavour, and pleasant aroma, as well as for being a source of vitamin C.

  14. 新型改良哈氏活动保持器在磨牙症正畸患者中的运用%Application of modified Hawley's mechanical retainer to patients with tooth clinching or bruxism

    Institute of Scientific and Technical Information of China (English)

    钱文娴

    2007-01-01

    目的 探讨新型改良哈式保持器在夜间紧咬牙或夜磨牙正畸患者中的应用效果.方法 选取9例在正畸治疗结束后仍有紧咬牙或夜磨牙的患者,予戴用新型哈式保持器1~2年,观察其预防夜磨牙与紧咬牙对矫治效果的影响. 结果 戴用新型哈式活动保持器后解除了患者因晚上紧咬牙或夜磨牙而引起的矫治结果的不稳定.结论 对于正畸结束后仍有紧咬牙或夜磨牙的患者给予戴用新型哈式活动保持器,不仅能够较好地保持矫治结果,还可以对紧咬牙及夜磨牙的现象给予一定的治疗,简单实用.

  15. Efecto de la altura de poda de formación en la arquitectura de plantas de camu camu (Myrciaria dubia H.B.K. Mc Vaugh en la estación experimental del IIAP, Ucayali, Perú.

    Directory of Open Access Journals (Sweden)

    Carlos Abanto

    2011-01-01

    Full Text Available Con el objetivo de evaluar la respuesta de las plantas de camu camu en plantaciones iniciales sometidas a podas de formación, se instaló un experimento en la EE - IIAP - Ucayali, bajo un Diseño de Bloques Completos al Azar con 3 repeticiones, considerando 20 plantas por unidad experimental. Los tratamientos consist ieron en realizar podas a diferentes alturas desde la base del tallo, se consideró T0 [testigo sin poda]; T1 [poda a 10 cm de la base]; T2 [poda a 20cm de la base] y T3 [poda a 40cm de la base] en plantas de 1.5 m de altura en promedio, procedentes de semi llas de la cuenca del rio Putumayo. Se evaluó el número de brotes, longitud de brotes, altura de planta, diámetro basal, diámetro de copa y número de ramas. Luego de 15 meses de evaluación se encontró diferencias significativas entre las variables estudiad as excepto en diámetro de copa. En altura sobresale el T0 [testigo sin poda]; los tratamientos restantes se comportaron de forma similar, superando al testigo en 267%. Así mismo, para el diámetro basal se halló que el T1 [poda a 10 cm de la base] se compo rtó mejor con un valor promedio de 1.96 cm frente al testigo con 1.7cm; Para el número de ramas la poda tuvo una influencia positiva, con un promedio de 13.4 ramas frente al T0 [testigo sin poda]; con 3.1 ramas, con lo cual se demostró que la poda de f ormación incrementa hasta un 432.3%.

  16. Introduction of foreign DNA into the water flea, Daphnia magna, by electroporation.

    Science.gov (United States)

    Kato, Yasuhiko; Kobayashi, Kaoru; Watanabe, Hajime; Iguchi, Taisen

    2010-03-01

    Daphnids inhabit a diverse array of aquatic environments and they are a good model for understanding response and adaptation to environmental changes and they have been used one of standard organisms in ecotoxicology. Recent progress of genomics changed the tools for analyzing responses of daphnids, because gene expression changes can be observed before the emergence of prominent adverse effect such as immobility of the organism. Thus understanding of biological changes from gene expression level can be one of the sensitive tools for the evaluation of environmental response of organisms. However, there was no technique for genetic manipulation in daphnids. Hence, we have developed a gene introduction technique based on electroporation. There are two critical points for the successful introduction of foreign DNA into D. magna. (1) Injection of DNA into blood stream. (2) Usage of very low voltage for the electroporation. The injected DNA containing green fluorescent protein (GFP) could be introduced daphnids and the expression of GFP could be detected in living daphnids. This is the first report of gene introduction to daphnids and, together with the emerging genome sequences, will be useful for the expanding our use of daphnid in ecotoxicology.

  17. Integral Monitored Retrievable Storage (MRS) Facility conceptual design report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1985-09-01

    In April 1985, the Department of Energy (DOE) selected the Clinch River site as its preferred site for the construction and operation of the monitored retrievable storage (MRS) facility (USDOE, 1985). In support of the DOE MRS conceptual design activity, available data describing the site have been gathered and analyzed. A composite geotechnical description of the Clinch River site has been developed and is presented herein. This report presents Clinch River site description data in the following sections: general site description, surface hydrologic characteristics, groundwater characteristics, geologic characteristics, vibratory ground motion, surface faulting, stability of subsurface materials, slope stability, and references. 48 refs., 35 figs., 6 tabs.

  18. Espécies novas de Blaptica do Rio Grande do Sul, Brasil (Blattaria, Blaberidae, Blaberinae) New species of Blaptica from Rio Grande do Sul, Brazil (Blattaria, Blaberidae, Blaberinae)

    OpenAIRE

    Sonia Maria Lopes; Edivar Heeren de Oliveira

    2005-01-01

    Cinco novas espécies de Blaptica Stål, 1875 do Estado do Rio Grande do Sul, Brasil são descritas e apresentadas ilustrações de Blaptica dubia.Five new species of Blaptica Stål, 1875 from Rio Grande do Sul State, Brazil are described and illustrations of Blaptica dubia are presented.

  19. Anorectal agenesis with rectovaginal fistula: A rare/regional variant

    Directory of Open Access Journals (Sweden)

    Subhasis Roy Choudhury

    2017-01-01

    Conclusion: RVF with anorectal agenesis is a rare/regional variant of female ARMs. Clinical examination along with distal colostogram, EUA, and endoscopy clinches the diagnosis. Anorectal reconstruction by posterior sagittal anorectoplasty results in a satisfactory outcome.

  20. Quantum chemistry based quantitative structure-activity relationships for modeling the (sub)acute toxicity of substituted mononitrobenzenes in aquatic systems

    NARCIS (Netherlands)

    Zvinavashe, E.; Murk, A.J.; Vervoort, J.; Soffers, A.E.M.F.; Freidig, A.; Rietjens, I.M.C.M.

    2006-01-01

    Fifteen experimental literature data sets on the acute toxicity of substituted nitrobenzenes to algae (Scenedesmus obliquus, Chlorella pyrenoidosa, C. vulgaris), daphnids (Daphnia magna, D. carinata), fish (Cyprinus carpio, Poecilia reticulata), protozoa (Tetrahymena pyriformis), bacteria (Phosphoba

  1. Quantum chemistry based QSAR prediction and priority setting for toxicity of nitrobenzenes on EINECS list

    NARCIS (Netherlands)

    Zvinavashe, E.; Murk, A.J.; Vervoort, J.J.M.; Soffers, A.E.M.F.; Freidig, A.; Rietjens, I.M.C.M.

    2006-01-01

    Fifteen experimental literature data sets on the acute toxicity of substituted nitrobenzenes to algae (Scenedesmus obliquus, Chlorella pyrenoidosa, C. vulgaris), daphnids (Daphnia magna, D. carinata), fish (Cyprinus carpio, Poecilia reticulata), protozoa (Tetrahymena pyriformis), bacteria (Phosphoba

  2. diel vertical migration of zooplankton in a hypertrophic shallow ...

    African Journals Online (AJOL)

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    In this investigation DVM by zooplankton is studied in a hypertrophic shallow lake in Germany. The ... they have intimately evolved through time. This ..... seemed to show similar patterns as the daphnids at ..... Estuaries 25(2):296–307. 8.

  3. Quantum chemistry based quantitative structure-activity relationships for modeling the (sub)acute toxicity of substituted mononitrobenzenes in aquatic systems

    NARCIS (Netherlands)

    Zvinavashe, E.; Murk, A.J.; Vervoort, J.; Soffers, A.E.M.F.; Freidig, A.; Rietjens, I.M.C.M.

    2006-01-01

    Fifteen experimental literature data sets on the acute toxicity of substituted nitrobenzenes to algae (Scenedesmus obliquus, Chlorella pyrenoidosa, C. vulgaris), daphnids (Daphnia magna, D. carinata), fish (Cyprinus carpio, Poecilia reticulata), protozoa (Tetrahymena pyriformis), bacteria

  4. Espécies novas de Blaptica do Rio Grande do Sul, Brasil (Blattaria, Blaberidae, Blaberinae New species of Blaptica from Rio Grande do Sul, Brazil (Blattaria, Blaberidae, Blaberinae

    Directory of Open Access Journals (Sweden)

    Sonia Maria Lopes

    2005-03-01

    Full Text Available Cinco novas espécies de Blaptica Stål, 1875 do Estado do Rio Grande do Sul, Brasil são descritas e apresentadas ilustrações de Blaptica dubia.Five new species of Blaptica Stål, 1875 from Rio Grande do Sul State, Brazil are described and illustrations of Blaptica dubia are presented.

  5. Efeito da omissão de macronutrientes e boro no crescimento, nos sintomas de deficiências nutricionais e na composição mineral de plantas de camucamuzeiro Effect of omission of macronutrient and boron on growth, on symptoms of nutritional deficiency and mineral composition in camucamuzeiro plants (Myrciaria dubia

    Directory of Open Access Journals (Sweden)

    Ismael de Jesus Matos Viégas

    2004-08-01

    Full Text Available Com o objetivo de avaliar o efeito da omissão de macronutrientes e do micronutriente boro no crescimento, nos sintomas de deficiências nutricionais e na composição mineral em plantas de camucamuzeiro, conduziu-se experimento em casa de vegetação, mediante a técnica do elemento faltante. O delineamento experimental foi o inteiramente casualizado, com quatro repetições e oito tratamentos, sendo completo (N, P, K, Ca, Mg, S e micronutrientes e omissão individual de N, P, K, Ca, Mg, S e B. Os sintomas visuais de deficiências foram, de modo geral, de fácil caracterização para todos os nutrientes. Com exceção do fósforo, as omissões dos demais nutrientes afetaram a produção de matéria seca, quando comparados ao tratamento completo. Com base nos teores em g kg-1, dos macronutrientes, e em mg kg-1, do micronutriente boro nas folhas, infere-se em uma primeira aproximação dos valores adequados (completo, ou seja: 16,9 a 18,2 de N ; 1,2 a 1,9 de P; 5,2 a 6,0 de K; 9,9 a 11,7 de Ca; 1,4 a 3,6 de Mg; 2,4 a 2,8 de S ; 8,4 a 9,5 de B e do deficiente (omissão , 6,5 a 7,9 de N ; =0,9 de P; =1,7 de K ; 5,4 a 6,5 de Ca; =0,7 de Mg; 0,7 a 1,2 de S e 1,1 a 1,9 de BThe effects of omission of macronutrient and boron on growth, on symptoms of nutritional deficiency and mineral composition of plants of "camucamuzeiro" were evaluated. The experiment was carried out in a greenhouse, by means of the missing element technique. The experimental design was completely randomized, with eight treatments and four repetitions, including complete (N, P, K, Ca, Mg, S and micronutrients and individual omission of N, P, K, Ca, Mg, S and B. The visual symptoms of deficiency were easily characterized for all the nutrients. Excepting for P, dry mass was affected by the omission of all the other nutrients, when compared with the complete treatment. Based on the macronutrient (g kg-1 and on the micronutrient boron (mg kg-1 on leaves contents, a first approach of the adequate values is inferred as being: N= 16,9 to 18,2; P= 1,2 to 1,9; K= 5,2 to 6,0; C= 9,9 to 11,7; Mg = 1,4 to 3,6; S= 2,4 to 2,8; and B= 8,4 to 9,5 for the complete treatment, and N= 6,5 to 7,9; P= 0,9; K= 1,7; Ca = 5,4 to 6,5; Mg = 0,7; S= 0,7 to 1,2 and B= 1,1 to 1,9 for the deficient ones (omission.

  6. Toxicity of inorganic and organic selenium to Daphnia magna (cladocera) and Chironomus riparius (diptera)

    Science.gov (United States)

    Ingersoll, Christopher G.; Dwyer, F.J.; May, T.W.

    1990-01-01

    Elevated concentrations of selenium (Se) have been previously measured in biota sampled from the Kesterson National Wildlife Refuge (KNWR) in the San Joaquin Valley of central California. We conducted acute and chronic toxicity tests with the cladoceran Daphnia magna and the midge Chironomus riparius to determine the toxicity or bioaccumulation of waterborne Se in a reconstituted water similar to the San Joaquin River. Daphnids were more acutely sensitive than midges to the toxic effects of inorganic Se. An organic form of Se (seleno-[L]-methionine) was extremely toxic to daphnids, but was relatively nontoxic to midges. In long-term exposure to a 6:1 mixture of selenate to selenite (a mixture representative of KNWR), the emergence time of adult midges was delayed at Se concentrations ≥ 837 μg/L. Daphnid reproduction and intrinsic rate of natural increase (r) were reduced at Se concentrations ≥ 348 μg/L and growth of adults was reduced at ≥ 156 μg/L. Whole body Mg, K and Na concentrations in daphnids were not affected by chronic Se exposure; however, whole body Ca concentration increased at intermediate Se exposure concentrations. In addition, whole body Cl concentration was reduced at 711 μg Se/L. Daphnids accumulated potentially toxic concentrations of Se from water that may adversely affect fish or waterfowl through the food chain.

  7. Comparative Developmental Staging of Female and Male Water Fleas Daphnia pulex and Daphnia magna During Embryogenesis.

    Science.gov (United States)

    Toyota, Kenji; Hiruta, Chizue; Ogino, Yukiko; Miyagawa, Shinichi; Okamura, Tetsuro; Onishi, Yuta; Tatarazako, Norihisa; Iguchi, Taisen

    2016-02-01

    The freshwater crustacean genus Daphnia has been used extensively in ecological, developmental and ecotoxicological studies. Daphnids produce only female offspring by parthenogenesis under favorable conditions, but in response to various unfavorable conditions and external stimuli, they produce male offspring. Although we reported that exogenous exposure to juvenile hormones and their analogs can induce male offspring even under female-producing conditions, we recently established a male induction system in the Daphnia pulex WTN6 strain simply by changing day-length. This male and female induction system is suitable for understanding the innate mechanisms of sexual dimorphic development in daphnids. Embryogenesis has been described as a normal plate (developmental staging) in various daphnid species; however, all studies have mainly focused on female development. Here, we describe the developmental staging of both sexes during embryogenesis in two representative daphnids, D. pulex and D. magna, based on microscopic time-course observations. Our findings provide the first detailed insights into male embryogenesis in both species, and contribute to the elucidation of the mechanisms underlying sexual differentiation in daphnids.

  8. Floral biology of two Vanilloideae (Orchidaceae) primarily adapted to pollination by euglossine bees.

    Science.gov (United States)

    Pansarin, E R; Pansarin, L M

    2014-11-01

    Vanilloideae comprises 15 genera distributed worldwide, among which are Vanilla and Epistephium (tribe Vanilleae). Based on field and laboratory investigations, the pollination biology of V. dubia and E. sclerophyllum was analysed. The former was surveyed in a semi-deciduous mesophytic forest at the biological reserve of Serra do Japi and in a marshy forest at the city of Pradópolis, southeastern Brazil. The latter was examined in rocky outcrop vegetation in the Chapada Diamantina, northeastern Brazil. In the studied populations, the tubular flowers of V. dubia and E. sclerophyllum were pollinated by bees. Pollen was deposited on either their scutellum (V. dubia) or scutum (E. sclerophyllum). The mentum region of V. dubia is dry, whereas that of E. sclerophyllum presents a small quantity of dilute nectar. Flowers of E. sclerophyllum are scentless, while those of V. dubia are odoriferous. Although V. dubia is self-compatible, it needs a pollinator to produce fruit. In contrast, E. sclerophyllum sets fruit through spontaneous self-pollination, but biotic pollination also occurs. Both species are primarily adapted to pollination by euglossine bees. Pollination by Euglossina seems to have occurred at least twice during the evolution of Vanilleae. Furthermore, shifts between rewarding and reward-free flowers and between autogamous and allogamous species have been reported among vanillas. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  9. The protective roles of TiO2 nanoparticles against UV-B toxicity in Daphnia magna.

    Science.gov (United States)

    Liu, Jie; Wang, Wen-Xiong

    2017-03-22

    Aquatic environments are increasingly under environmental stress due to ultraviolet (UV) radiation and potential inputs of nanoparticles with intense application of nanotechnology. In this study, we investigated the interaction between UV-B radiation and titanium nanoparticles (TiO2-NPs) in a model freshwater cladoceran Daphnia magna. UV-B toxicity to Daphnia magna was examined when the daphnids were exposed to a range of TiO2-NPs concentrations with an initial 5 or 10min of 200μW/cm(2) UV-B radiation. In addition, UV-B toxicity was also examined in the presence of TiO2-NPs in the body of daphnids. Our results demonstrated that the daphnid mortality under UV-B radiation decreased significantly in the presence of TiO2-NPs both in the water and in the body, indicating that TiO2-NPs had some protective effects on D. magna against UV-B. Such protective effect was mainly caused by the blockage of UV-B by TiO2-NPs adsorption. UV-B produced reactive oxygen species (ROS) in the water and in the daphnids, which was not sufficient to cause mortality of daphnids over short periods of radiation. Previous studies focused on the effects of TiO2-NPs on the toxicity of total UV radiation, and did not attempt to differentiate the potential diverse roles of UV-A and UV-B. Our study indicated that TiO2-NPs may conversely protect the UV-B toxicity to daphnids.

  10. Anticipatory maternal effects in two different clones of Daphnia magna in response to food shortage

    Directory of Open Access Journals (Sweden)

    Valeria ROSSI

    2011-08-01

    Full Text Available The effects of food shortage on growth, fecundity, male production and offspring size and starvation tolerance in two different clones of Daphnia magna (Clone L and Clone P were evaluated by disentangling the effects of resource depletion and crowding per se. Three experimental conditions were tested: high food - low daphnid density (the optimum, low food - low daphnid density and high food - high daphnid density. In the two first conditions, daphnids experienced the same population density but they had different food availability. In the two latter conditions, daphnids had the same per capita, low, food availability but they lived at different algae and daphnid densities. Moreover, the response of crowded females to recovery at high food availability and low population density was evaluated. Low food availability reduced growth and fecundity of both clones and increased male production only in the Clone L. Crowding per se did not affect growth but reduced fecundity. In both clones, low food availability due to low algae density enhanced investment in offspring size and resistance to starvation. In response to food shortage either due to low algae density and to crowding, Clone P increased the investment in offspring size and starvation tolerance but reduced fecundity to a lesser extent than Clone L and did not produce males. Clone L, in response to food shortage due to crowding at high algae density, increased development time, produced more males, as at low algae density, but halved fecundity producing offspring that were not starvationtolerant. These results might reflect differences in anticipatory maternal effects between clones and suggest that neonate quality varies according to either, the environment the mother experienced and the competitive environment the neonates will cope due to their mother life strategy.

  11. Multigenerational effects of carbendazim in Daphnia magna.

    Science.gov (United States)

    Silva, Ana Rita R; Cardoso, Diogo N; Cruz, Andreia; Pestana, João L T; Mendo, Sónia; Soares, Amadeu M V M; Loureiro, Susana

    2017-02-01

    Carbendazim is a fungicide largely used in agriculture as a plant protection product. As a result of agricultural runoffs, drainage, and leaching, it reaches surface waters at concentrations possibly hazardous to aquatic communities. Because of potential and continuous release of carbendazim to aquatic systems, long-term exposure to aquatic organisms should be addressed. To fill the knowledge gap, the present study evaluated the responses of multiple generations of Daphnia magna (clone K6) to an environmentally relevant concentration of carbendazim (5 μg/L). Twelve successive generations were evaluated, and the effects in these offspring were compared with those from a control population. Neonates' fitness was assessed through immobilization, reproduction, and feeding activity tests, along with the comet assay for in vivo DNA damage evaluation. Recovery from long-term exposure was also assessed. In the F5 generation, the results revealed that when daphnids were re-exposed to carbendazim, DNA damage was higher in daphnids continuously exposed to carbendazim than those from clean medium. After daphnids were moved to a clean medium, a low recovery potential was observed for DNA damage. Daphnids exposed continuously for 6 generations (F6) to carbendazim displayed an increase in feeding rates when re-exposed to carbendazim compared with F6 daphnids reared in clean medium. Continuous exposure of daphnids to carbendazim induced a significant increase in DNA damage from the F0 to the F12 generation. Deleterious effects of the multigenerational exposure to carbendazim were more prominent at a subcellular level (DNA damage) compared with the individual level. Environ Toxicol Chem 2017;36:383-394. © 2016 SETAC. © 2016 SETAC.

  12. [Ovine dicrocoeliasis: incidence of climatic factors and share in the setting of a forecasting method (author's transl)].

    Science.gov (United States)

    Badie, A

    1978-01-01

    Study of annual activity cycle of ants parasited with Dicrocoelium lanceolatum. Effect of some climatic factors (temperature, rainfall) on seasonal variations of the number of clinching parasited ants. A close analysis of the data displays a double correlation: the increase of the number of clinching ants indirectly brought about by precipitations and this with some delay; a strong decrease by high temperatures in the height of summer. Setting of a calendar including the different stages of the developing cycle of Dicrocoelium lanceolatum in Limousin and proposition of a forecasting technic established from land observations.

  13. Advanced joining techniques for modern lightweight steel construction; Techniques d`assemblage des aciers a haute resistance pour vehicule leger

    Energy Technology Data Exchange (ETDEWEB)

    Stegemann, T. [Thyssen Stahl AG, Duisburg (Germany); Hahn, O.; Schulte, A. [Paderborn Univ. (Gesamthochschule) (Germany)

    1998-01-01

    New high-strength steel grades in combination with modern joining techniques contribute to optimize properties of the joints. Specially heatless joining techniques improve the fatigue properties of the joints as well as the crash behaviour. Such mechanical joining techniques are clinching and self piercing riveting. But the combined joining techniques e.g., weld bonding, clinching combined with bonding are also effective in the case of high-strength steel sheets. The minor heat input of laser-beam welds can also be used to join high strength steels to stiffer light weight structures. (authors)

  14. Multi-linear regression analysis, preliminary biotic ligand modeling, and cross species comparison of the effects of water chemistry on chronic lead toxicity in invertebrates.

    Science.gov (United States)

    Esbaugh, A J; Brix, K V; Mager, E M; De Schamphelaere, K; Grosell, M

    2012-03-01

    The current study examined the chronic toxicity of lead (Pb) to three invertebrate species: the cladoceran Ceriodaphnia dubia, the snail Lymnaea stagnalis and the rotifer Philodina rapida. The test media consisted of natural waters from across North America, varying in pertinent water chemistry parameters including dissolved organic carbon (DOC), calcium, pH and total CO(2). Chronic toxicity was assessed using reproductive endpoints for C. dubia and P. rapida while growth was assessed for L. stagnalis, with chronic toxicity varying markedly according to water chemistry. A multi-linear regression (MLR) approach was used to identify the relative importance of individual water chemistry components in predicting chronic Pb toxicity for each species. DOC was an integral component of MLR models for C. dubia and L. stagnalis, but surprisingly had no predictive impact on chronic Pb toxicity for P. rapida. Furthermore, sodium and total CO(2) were also identified as important factors affecting C. dubia toxicity; no other factors were predictive for L. stagnalis. The Pb toxicity of P. rapida was predicted by calcium and pH. The predictive power of the C. dubia and L. stagnalis MLR models was generally similar to that of the current C. dubia BLM, with R(2) values of 0.55 and 0.82 for the respective MLR models, compared to 0.45 and 0.79 for the respective BLMs. In contrast the BLM poorly predicted P. rapida toxicity (R(2)=0.19), as compared to the MLR (R(2)=0.92). The cross species variability in the effects of water chemistry, especially with respect to rotifers, suggests that cross species modeling of invertebrate chronic Pb toxicity using a C. dubia model may not always be appropriate.

  15. Joining by plastic deformation

    DEFF Research Database (Denmark)

    Mori, Ken-ichiro; Bay, Niels; Fratini, Livan

    2013-01-01

    opportunities to design new products through joining dissimilar materials. This paper aims to provide an overview of the state of the art in such joining processes, including cold welding, friction stir welding, self-pierce riveting, mechanical clinching and joining by forming. The paper includes description...... of the mechanism of joint formation, and analysis of joint performance and applicability. © 2013 CIRP....

  16. Diving Into History

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Three divers have made history at the 13th FINA World Championships held in Rome on July 17-August 2. Guo Jingjing, the Chinese diving queen who clinched the gold in the women’s 3-meter springboard on July 21, became the first

  17. Incorporation of phenomenological uncertainties in probabilistic safety analysis - application to LMFBR core disruptive accident energetics

    Energy Technology Data Exchange (ETDEWEB)

    Najafi, B; Theofanous, T G; Rumble, E T; Atefi, B

    1984-08-01

    This report describes a method for quantifying frequency and consequence uncertainty distribution associated with core disruptive accidents (CDAs). The method was developed to estimate the frequency and magnitude of energy impacting the reactor vessel head of the Clinch River Breeder Plant (CRBRP) given the occurrence of hypothetical CDAs. The methodology is illustrated using the CRBR example.

  18. The New Iron Man

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Sinosteel wins a hard-fought victory in the marathon battle for Australia’s Midwest Sinosteel Corp.,one of China’s larg- est steelmakers,has finally clinched its AU$1.36 billion($1.31 billion) takeover of Midwest Corp.,a Perth (Australia)-based iron ore miner,after a

  19. A Holistic Approach to Taxonomic Evaluation of Two Closely Related Endangered Freshwater Mussel Species, the Oyster Mussel (Epioblasma capsaeformis) and Tan Riffleshell (Epioblasma florentina walkeri) (Bivalvia: Unionidae)

    OpenAIRE

    Jones, Jess Walter

    2004-01-01

    A Holistic Approach to Taxonomic Evaluation of Two Closely Related Endangered Freshwater Mussel Species, the Oyster Mussel (Epioblasma capsaeformis) and Tan Riffleshell (Epioblasma florentina walkeri) (Bivalvia: Unionidae) by Jess W. Jones Richard J. Neves, Chairperson Fisheries and Wildlife Sciences (ABSTRACT) Primers for 10 polymorphic DNA microsatellite loci were developed and characterized for the endangered oyster mussel Epioblasma capsaeformis from the Clinch River, TN. Microsatellite...

  20. Simulant-material experimental investigation of flow dynamics in the CRBR Upper-Core Structure

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, D.; Starkovich, V.S.; Chapyak, E.J.

    1982-09-01

    The results of a simulant-material experimental investigation of flow dynamics in the Clinch River Breeder Reactor (CRBR) Upper Core Structure are described. The methodology used to design the experimental apparatus and select test conditions is detailed. Numerous comparisons between experimental data and SIMMER-II Code calculations are presented with both advantages and limitations of the SIMMER modeling features identified.

  1. DeflateGate: The "Pressure" of Getting the Game Ball Right

    Science.gov (United States)

    Cantu, Diana V.

    2015-01-01

    On February 1, 2015, the New England Patriots clinched a 28-24 point win against the Seattle Seahawks in Super Bowl XLIX. Going into the game, the Patriots were shrouded in controversy regarding possible deflated footballs in their American Football Conference (AFC) Championship game against the Indianapolis Colts, most notably known as…

  2. Posterior vaginal wall Gartner′s duct cyst

    Directory of Open Access Journals (Sweden)

    Ripan Bala

    2015-01-01

    Full Text Available Cyst of posterior vaginal wall is very rare. This case relates to a patient who presented with polypoidal mass protruding out from vagina which could have been easily mistaken as uterovaginal prolapse, but appropriate clinical evaluation supported with investigations clinched the diagnosis easily.

  3. 78 FR 57611 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List Alabama Shad as...

    Science.gov (United States)

    2013-09-19

    ... 20, 2010, the Center for Biological Diversity (CBD), Alabama Rivers Alliance, Clinch Coalition... integrity or fragmentation), and the potential contribution of identified demographic risks to extinction... in medium to large flowing rivers from the Mississippi River drainage to the Suwannee River, Florida...

  4. Development and validation of an individual based Daphnia magna population model: The influence of crowding on population dynamics

    NARCIS (Netherlands)

    Preuss, T.G.; Hammers-Wirtz, M.; Hommen, U.; Rubach, M.N.; Ratte, H.T.

    2009-01-01

    An individual-based model was developed to predict the population dynamics of Daphnia magna at laboratory conditions from individual life-history traits observed in experiments with different feeding conditions. Within the model, each daphnid passes its individual life cycle including feeding on alg

  5. Uptake and effects of microplastic textile fibers on freshwater crustacean Daphnia magna.

    Science.gov (United States)

    Jemec, Anita; Horvat, Petra; Kunej, Urban; Bele, Marjan; Kržan, Andrej

    2016-12-01

    Microplastic fibers (MP) from textile weathering and washing are increasingly being recognized as environmental pollutants. The majority of studies on the bioavailability and effects of microplastic focused on small polystyrene spherical plastic particles, while less data are available for fibers and for other materials besides polystyrene. We investigated the ingestion and effects of ground polyethylene terephthalate (PET) textile microfibers (length range: 62-1400 μm, width 31-528 μm, thickness 1-21.5 μm) on the freshwater zooplankton crustacean Daphnia magna after a 48 h exposure and subsequent 24 h of recovery in MP free medium and algae. The majority of ingested fibers by D. magna were around 300 μm, but also some very large twisted MP fibers around 1400 μm were found inside the gut. Exposure to these fibers results in increased mortality of daphnids after 48 h only in the case where daphnids were not pre-fed with algae prior to experiment, but no effect was found when daphnids were fed before the experiments. Regardless of the feeding regime, daphnids were not able to recover from MP exposure after additional 24 h incubation period in a MP free medium with algae. The uptake and effects of PET textile MP on D. magna are presented here for the first time.

  6. Cyanobacterial protease inhibitor microviridin J causes a lethal molting disruption in Daphnia pulicaria.

    Science.gov (United States)

    Rohrlack, Thomas; Christoffersen, Kirsten; Kaebernick, Melanie; Neilan, Brett A

    2004-08-01

    Laboratory experiments identified microviridin J as the source of a fatal molting disruption in Daphnia species organisms feeding on Microcystis cells. The molting disruption was presumably linked to the inhibitory effect of microviridin J on daphnid proteases, suggesting that hundreds of further cyanobacterial protease inhibitors must be considered potentially toxic to zooplankton.

  7. TYPES, USES, AND LOCATIONS OF REAL-TIME BIOLOGICAL MONITORING IN EUROPE AND THE US

    Science.gov (United States)

    Many dffferent types of real-time biological monitoring (fish behavior and current, daphnid dynamic and toximeter, clam monitors, algae, and luminescent bacteria) have been used in several countries (Germany, Netherlands, France, England( and many locations in Europe. Only a few ...

  8. Acute toxicity of fire control chemicals to Daphnia magna (Straus) and Selenastrum capricornutum (Printz).

    Science.gov (United States)

    McDonald, S F; Hamilton, S J; Buhl, K J; Heisinger, J F

    1996-02-01

    Acute toxicity tests were conducted exposing Daphnia magna Straus (daphnid) in soft and hard reconstituted waters (hardness 42 and 162 mg/liter as CaCO3, respectively), and Selenastrum capricornutum Printz (algae) in ASTM algal assay medium (hardness 15 mg/liter as CaCO3) to fire retardants Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F, and foam suppressants Phos-Check WD-881 and Silv-Ex. The chemicals were slightly toxic to practically harmless to daphnids and moderately toxic to algae. Water quality did not consistently alter the toxicity of the test chemicals to daphnids. The most toxic chemical to daphnids was Silv-Ex (48-hr EC50 7 mg/liter in soft and hard waters), whereas the least toxic chemical to daphnids was Fire-Trol LCG-R (48-hr EC50 848 mg/liter in soft water, 813 mg/liter in hard water). The most toxic chemical to algae was Fire-Trol LCG-R (96-hr IC50 10 mg/liter), and the least toxic chemical was Phos-Chek D75-F (96-hr IC50 79 mg/liter). Un-ionized ammonia concentrations near the EC50 or IC50 value in tests with the Fire-Trol compounds were frequently equal to or above reported LC50 un-ionized ammonia concentrations. Un-ionized ammonia concentrations in tests with Phos-Chek D75-F were low, thus other toxic components present in the compounds probably contributed to the toxicity. When compared to the daphnids tested in ASTM soft water, the Fire-Trol compounds were most toxic to algae, whereas Phos-Chek D75-F and the foam suppressants were most toxic to daphnids. The results of these tests are comparable to those obtained from research conducted in other laboratories with the same species and similar chemicals. Accidental entry of fire-fighting chemicals into aquatic environments could adversely affect algae and aquatic invertebrates, thus disrupting ecosystem function.

  9. Bacterial epibionts of Daphnia: a potential route for the transfer of dissolved organic carbon in freshwater food webs

    Science.gov (United States)

    Eckert, Ester M; Pernthaler, Jakob

    2014-01-01

    The identification of interacting species and elucidation of their mode of interaction may be crucial to understand ecosystem-level processes. We analysed the activity and identity of bacterial epibionts in cultures of Daphnia galeata and of natural daphnid populations. Epibiotic bacteria incorporated considerable amounts of dissolved organic carbon (DOC), as estimated via uptake of tritiated leucine: three times more tracer was consumed by microbes on a single Daphnia than in 1 ml of lake water. However, there was virtually no incorporation if daphnids were anaesthetised, suggesting that their filtration activity was essential for this process. Microbial DOC uptake could predominantly be assigned to microbes that were located on the filter combs of daphnids, where the passage of water would ensure a continuously high DOC supply. Most of these bacteria were Betaproteobacteria from the genus Limnohabitans. Specifically, we identified a monophyletic cluster harbouring Limnohabitans planktonicus that encompassed sequence types from D. galeata cultures, from the gut of Daphnia magna and from daphnids of Lake Zurich. Our results suggest that the epibiotic growth of bacteria related to Limnohabitans on Daphnia spp. may be a widespread and rather common phenomenon. Moreover, most of the observed DOC flux to Daphnia in fact does not seem to be associated with the crustacean biomass itself but with its epibiotic microflora. The unexplored physical association of daphnids with heterotrophic bacteria may have considerable implications for our understanding of carbon transfer in freshwater food webs, that is, a trophic ‘shortcut' between microbial DOC uptake and predation by fish. PMID:24694716

  10. Protective effects of ectoine on heat-stressed Daphnia magna.

    Science.gov (United States)

    Adam, Bownik; Zofia, Stępniewska; Tadeusz, Skowroński

    2014-12-01

    Ectoine (ECT) is an amino acid produced and accumulated by halophilic bacteria in stressful conditions in order to prevent the loss of water from the cell. There is a lack of knowledge on the effects of ECT in heat-stressed aquatic animals. The purpose of our study was to determine the influence of ECT on Daphnia magna subjected to heat stress with two temperature gradients: 1 and 0.1 °C/min in the range of 23-42 °C. Time to immobilisation, survival during recovery, swimming performance, heart rate, thoracic limb movement and the levels of heat shock protein 70 kDa 1A (HSP70 1A), catalase (CAT) and nitric oxide species (NOx) were determined in ECT-exposed and unexposed daphnids; we showed protective effects of ECT on Daphnia magna subjected to heat stress. Time to immobilisation of daphnids exposed to ECT was longer when compared to the unexposed animals. Also, survival rate during the recovery of daphnids previously treated with ECT was higher. ECT significantly attenuated a rapid increase of mean swimming velocity which was elevated in the unexposed daphnids. Moreover, we observed elevation of thoracic limb movement and modulation of heart rate in ECT-exposed animals. HSP70 1A and CAT levels were reduced in the presence of ECT. On the other hand, NOx level was slightly elevated in both ECT-treated and unexposed daphnids, however slightly higher NOx level was found in ECT-treated animals. We conclude that the exposure to ectoine has thermoprotective effects on Daphnia magna, however their mechanisms are not associated with the induction of HSP70 1A.

  11. [Severianoia blapticola sp. n. (Oxyurida: Thelastomatidae): a new nematode species from blaberid cockroaches].

    Science.gov (United States)

    Guzeeva, E A

    2009-01-01

    A new nematode species of the genus Severianoia (Schwenk, 1926) Travassos, 1929, S. blapticola sp. n., is described from the hind gut of cockroach Blaptica dubia (Serville, 1839) from laboratory culture. The main morphological feature of S. blapticola sp. n. is the presence of columnar cuticular structures of different height on the ventral side of male posterior end. In the gut of B. dubia these nematodes coexist with another thelastomatid genus, Cranifera Kloss, 1960 [C. cranifera (Chitwood, 1932) Kloss, 1960]. Males of C. cranifera are characterized by the presence of cloacal projection and columnar structures on both dorsal and ventral sides of male posterior end.

  12. The acute and chronic toxicity of major geochemical ions to Hyalella azteca Ion interactions and comparisons to other species

    Science.gov (United States)

    We have previously reported that the acute and chronic toxicities of major geochemical ions (Na, K, Ca, Mg, Cl, SO4, HCO3) to Ceriodaphnia dubia can involve multiple, independent mechanisms. The toxicities of K, Mg, and Ca salts were best related to the chemical activity of the c...

  13. Biological Inventory Cape La Croix Creek Watershed, Cape Girardeau County, Missouri.

    Science.gov (United States)

    1977-01-01

    Centrics 703 - 35 1 . Permales Achnanthes minutissima 13 12 12.5 F yrnbella turgida 27 - 13.5 Pragilaria vauche2riae - 2541 127 Gornpfonema ol-ivaceum...CIIRYSOPIjYTA Mallomonas sp. - 73 5. . Centrales Melosira varians 2266 + 1131 Pennales Achnanthes sp. 20 - 10 A. lanceolata var. dubia - 170 85 A. linearis f

  14. The acute and chronic toxicity of major geochemical ions to Hyalella azteca Ion interactions and comparisons to other species

    Science.gov (United States)

    We have previously reported that the acute and chronic toxicities of major geochemical ions (Na, K, Ca, Mg, Cl, SO4, HCO3) to Ceriodaphnia dubia can involve multiple, independent mechanisms. The toxicities of K, Mg, and Ca salts were best related to the chemical activity of the c...

  15. TOXICITY OF FIPRONIL ENANTIOMERS TO THE WATER FLEA AND BLACK FLY

    Science.gov (United States)

    In this research, we analyzed the enantiomer-specific toxicity of fipronil using two aquatic invertebrate species. Acute toxicity to Ceriodaphnia dubia (water flea) indicated that the (+) enantiomer was significantly more toxic than the (-) enantiomer, with about a 3-fold differ...

  16. Insect lipid profile: aqueous versus organic solvent-based extraction methods

    NARCIS (Netherlands)

    Tzompa Sosa, D.A.; Yi, L.; Valenberg, van H.J.F.; Boekel, van M.A.J.S.; Lakemond, C.M.M.

    2014-01-01

    In view of future expected industrial bio-fractionation of insects, we investigated the influence of extraction methods on chemical characteristics of insect lipids. Lipids from Tenebrio molitor, Alphitobius diaperinus, Acheta domesticus and Blaptica dubia, reared in the Netherlands, were extracted

  17. Effect of the search image on the lizard ability to reveal a Batesian mimic

    OpenAIRE

    Beneš, Josef

    2016-01-01

    The effect of the search image on the ability of hand reared skinks (Chalcides sexlineatus) to reveal a "fake" Batesian mimic was tested with respect to their previous experience with palatable experimental prey (Guyana spotted cockroach Blaptica dubia) which served as a motivational prey as well as midsized mealworm beetle larvae (Tenebrio molitor). The red firebug (Pyrrhocoris apterus) was used as an aposematic model.

  18. Extraction and characterisation of protein fractions from five insect species

    NARCIS (Netherlands)

    Yi, L.; Lakemond, C.M.M.; Sagis, L.M.C.; Eisner-Schadler, V.R.; Huis, van A.; Boekel, van M.A.J.S.

    2013-01-01

    Tenebrio molitor, Zophobas morio, Alphitobius diaperinus, Acheta domesticus and Blaptica dubia were evaluated for their potential as a future protein source. Crude protein content ranged from 19% to 22% (Dumas analysis). Essential amino acid levels in all insect species were comparable with soybean

  19. Further notes on New Zealand Enantiobuninae (Opiliones, Neopilionidae, with the description of a new genus and two new species

    Directory of Open Access Journals (Sweden)

    Christopher Taylor

    2013-02-01

    Full Text Available Mangatangi parvum gen. n. and sp. and Forsteropsalis pureroa sp. n. are described from the North Island of New Zealand. Pantopsalis listeri (White 1849 and P. cheliferoides (Colenso 1882 are redescribed and no longer regarded as nomina dubia; P. luna (Forster 1944 is identified as a junior synonym of P. listeri. A key to Pantopsalis species is provided.

  20. Carideorum catalogus: the recent species of the dendrobranchiate, stenopodidean, procarididean and caridean shrimps (Crustacea: Decapoda)

    NARCIS (Netherlands)

    De Grave, S.; Fransen, C.H.J.M.

    2011-01-01

    A checklist of recent species of dendrobranchiate, stenopodidean, procarididean and caridean shrimps including synonyms and type localities. Also listed are unavailable names, larval names, nomina dubia and nomina nuda. A complete list of references to original descriptions of taxa listed is provide

  1. A taxonomic revision of the new world species of Sirthenea (Heteroptera: Reduviidae: Peiratinae)

    NARCIS (Netherlands)

    Willemse, L.

    1985-01-01

    The American species of Sirthenea are revised and keys to the 12 species and seven subspecies are given. Four new species and two new subspecies are described viz., S. ater (Brazil: Minas Geraes), S. dubia (Panama; Paraguay: Caaguazu. Argentina: Misiones; Entre Rios), S. ferdinandi (Argentina: Salta

  2. A taxonomic revision of the Malesian genus Trigonopleura Hook.f. (Euphorbiaceae)

    NARCIS (Netherlands)

    Welzen, van Peter C.; Bulalacao, Lolita J.; Ôn, van Tran

    1995-01-01

    Trigonopleura, a genus from W Malesia, has three species, the widespread T. malayana (Malay Peninsula, Sumatra, Borneo, Sulawesi) and the two endemic species T. dubia (Philippines) and T. macrocarpa (Sarawak, Kuching). The species differ slightly from each other in leaf size, colour, and margin, flo

  3. A taxonomic revision of the Malesian genus Trigonopleura Hook.f. (Euphorbiaceae)

    NARCIS (Netherlands)

    Welzen, van Peter C.; Bulalacao, Lolita J.; Ôn, van Tran

    1995-01-01

    Trigonopleura, a genus from W Malesia, has three species, the widespread T. malayana (Malay Peninsula, Sumatra, Borneo, Sulawesi) and the two endemic species T. dubia (Philippines) and T. macrocarpa (Sarawak, Kuching). The species differ slightly from each other in leaf size, colour, and margin,

  4. Assessment of the potential toxicity of a linear alkylbenzene sulfonate (LAS) to freshwater animal life by means of cladoceran bioassays.

    Science.gov (United States)

    Coelho, Katiuscia da Silva; Rocha, Odete

    2010-04-01

    The acute and chronic toxic effects of LAS on the cladocerans Daphnia similis, Ceriodaphnia dubia and Ceriodaphnia silvestrii were tested. Both types of toxicity bioassays and the methods of culture and stock maintenance of the test organisms conformed to the recommendations of ABNT (Brazilian Society of Technical Standards), which closely follow the standard methods of USEPA. The results obtained for EC(50) (48 h) were: 14.17 mg L(-1) for D. similis, 11.84 mg L(-1) for C. dubia and 13.52 mg L(-1) for C. silvestrii. In the chronic toxicity tests performed on C. dubia and C. silvestrii, there was a significant decrease in the fecundity of the exposed animals; the value of NOEC for C. dubia and C. silvestrii were 1.00 mg L(-1) and 2.50 mg L(-1), respectively. Cladoceran bioassays provided evidence that LAS concentration as low as 1.00 mg L(-1) can damage invertebrate animal life in freshwaters, concentrations that can be found in many eutrophic rivers and reservoirs.

  5. Variation in, and causes of, toxicity of cigarette butts to a cladoceran and microtox.

    Science.gov (United States)

    Micevska, T; Warne, M St J; Pablo, F; Patra, R

    2006-02-01

    Cigarette butts are the most numerically frequent form of litter in the world. In Australia alone, 24-32 billion cigarette butts are littered annually. Despite this littering, few studies have been undertaken to explore the toxicity of cigarette butts in aquatic ecosystems. The acute toxicity of 19 filtered cigarette types to Ceriodaphnia cf. dubia (48-hr EC50 (immobilization)) and Vibrio fischeri (30-min EC50 (bioluminescence)) was determined using leachates from artificially smoked cigarette butts. There was a 2.9- and 8-fold difference in toxicity between the least and most toxic cigarette butts to C. cf. dubia and V. fischeri, respectively. Overall, C. cf. dubia was more inherently sensitive than V. fischeri by a factor of approximately 15.4, and the interspecies relationship between C. cf. dubia and V. fischeri was poor (R(2) = 0.07). This poor relationship indicates that toxicity data for cigarette butts for one species could not predict or model the toxicity of cigarette butts to the other species. However, the order of the toxicity of leachates can be predicted. It was determined that organic compounds caused the majority of toxicity in the cigarette butt leachates. Of the 14 organic compounds identified, nicotine and ethylphenol were suspected to be the main causative toxicants. There was a strong relationship between toxicity and tar content and between toxicity and nicotine content for two of the three brands of cigarettes (R(2 )> 0.70) for C. cf. dubia and one brand for V. fischeri. However, when the cigarettes were pooled, the relationship was weak (R(2) < 0.40) for both test species. Brand affected the toxicity to both species but more so for V. fischeri.

  6. Quality Assurance Plan for the remedial investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, G.P.; Miller, D.E. (Automated Sciences Group, Inc., Oak Ridge, TN (United States))

    1992-12-01

    The Oak Ridge National Laboratory (ORNL) Waste Area Grouping (WAG) 2 Site Investigation (SI)includes the lower portion of the White Oak Creek (WOC) drainage and enbayment, and associated floodplain and subsurface environment. The ORNL main plant and the major waste storage and disposal facilities at ORNL are located in the WOC watershed and are drained by the WOC system to the Clinch River, located off-site. Environmental media are contaminated and continue to receive contaminants from hydrologically upgradient WAGS. WAG 2 is important as a conduit from upgradient areas to the Clinch River. The general objectives of the WAG 2 SI Project are to conduct a multimedia monitoring and characterization program to define and monitor the input of contaminants from adjacent WAGS, monitor and gather sufficient information for processes controlling or driving contaminant fluxes to construct an appropriate conceptual model for WAG 2, and prepare for the eventual remediation of WAG 2.

  7. Quality Assurance Plan for the remedial investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, G.P.; Miller, D.E. [Automated Sciences Group, Inc., Oak Ridge, TN (United States)

    1992-12-01

    The Oak Ridge National Laboratory (ORNL) Waste Area Grouping (WAG) 2 Site Investigation (SI)includes the lower portion of the White Oak Creek (WOC) drainage and enbayment, and associated floodplain and subsurface environment. The ORNL main plant and the major waste storage and disposal facilities at ORNL are located in the WOC watershed and are drained by the WOC system to the Clinch River, located off-site. Environmental media are contaminated and continue to receive contaminants from hydrologically upgradient WAGS. WAG 2 is important as a conduit from upgradient areas to the Clinch River. The general objectives of the WAG 2 SI Project are to conduct a multimedia monitoring and characterization program to define and monitor the input of contaminants from adjacent WAGS, monitor and gather sufficient information for processes controlling or driving contaminant fluxes to construct an appropriate conceptual model for WAG 2, and prepare for the eventual remediation of WAG 2.

  8. An evaluation of the aquatic hazard of cumene (isopropyl benzene).

    Science.gov (United States)

    Glickman, A H; Alexander, H C; Buccafusco, R J; Morris, C R; Francis, B O; Surprenant, D C; Ward, T J

    1995-08-01

    Cumene manufacturers were required under a TSCA Section 4(a) test rule to evaluate the aquatic toxicity of cumene to daphnids, rainbow trout, mysid shrimp, and sheepshead minnows. Because of cumene's high volatility (vapor pressure, 3.2 mm Hg at 20 degrees C), all tests were conducted under flowthrough conditions using a proportional diluter system. The 96-hr LC50s for rainbow trout, sheepshead minnow, and mysid shrimp, based on mean measured concentrations, were 4.8, 4.7, and 1.3 mg/liter, respectively. The 48-hr daphnid EC50 was 4.0 mg/liter. Although cumene is considered moderately toxic to aquatic organisms under rigorous laboratory conditions, its volatility and biodegradability greatly reduce its hazard to the aquatic environment.

  9. Rheoceptive mediators of graviperception in a water flea: Morphological implications of antennal-socket setae in daphnia magna

    Science.gov (United States)

    Meyers, D. G.

    1984-01-01

    Aquatic microcrustaceans of the genus Daphnia are known to orient to light during the day. At night, in the absence of visual cues, daphnids were suspected of maintaining equilibrium by monitoring the direction of gravity through their swimming antennae. Recent investigations using simulated, weightlessness conditions coupled with absence of illumination revealed hair like structures or setae on the basal, articulating socket of the antennae that, when surgically removed, resulted in disorientation. Given the simulated weightlessness or neutrally buoyant condition that eliminated sinking of the normally negatively buoyant Daphnia, it was proposed that the antennal socket setae function as rheoceptors stimulated by the upward rush of water currents during gravity induced, sinking phase of daphnid swimming movements. This rheoceptively mediated, gravity perception hypothesis is further supported by morphological investigations. Scanning electron micrographs indicate that antennal socket setae are anatomically similar to proprioceptors used by higher crustaceans to monitor gravitational direction.

  10. Protein kinase C is involved with upstream signaling of methyl farnesoate for photoperiod-dependent sex determination in the water flea Daphnia pulex

    Directory of Open Access Journals (Sweden)

    Kenji Toyota

    2017-02-01

    Full Text Available Sex determination of Daphnia pulex is decided by environmental conditions. We established a suitable experimental system for this study using D. pulex WTN6 strain, in which the sex of the offspring can be controlled by photoperiod. Long-day conditions induced females and short-day conditions induced males. Using this system, we previously found that methy farnesoate (MF, which is a putative innate juvenile hormone molecule in daphnids, is necessary for male sex determination and that protein kinase C (PKC is a candidate factor of male sex determiner. In this study, we demonstrated that a PKC inhibitor [bisindolylmaleimide IV (BIM] application strongly suppressed male offspring induction in the short-day condition. Moreover, co-treatment of BIM with MF revealed that PKC signaling acts upstream of MF signaling for male sex determination. This is the first experimental evidence that PKC is involved in the male sex determination process associated with methyl farnesoate signaling in daphnid species.

  11. Gravity receptors in a microcrustacean water flea - Sensitivity of antennal-socket setae in Daphnia magna

    Science.gov (United States)

    Meyers, D. G.; Farmer, J. M.

    1982-01-01

    Gravity receptors of Dephnia magna were discovered on the basal segment of the swimming antennae and were shown to respond to upward water currents that pass the animal as it sinks between swimming strokes. Sensitivity of the gravity perceiving mechanism was tested by subjecting daphnids to a series of five decreasingly dense aqueous solutions (neutral density to water) in darkness (to avoid visual cues). Three-dimensional, video analysis of body position (pitch, yaw and roll) and swimming path (hop and sink, vertical and horizontal patterns) revealed a gradual threshold that occurred near a density difference between the animal and its environment of less than 0.25%. Because daphnids do not sink but continue to slide after stroking in the increased density solutions, gravity perception appears to occur during a vertical swing of the longitudinal body axis to the vertical plane, about their center of gravity, and, thereby, implies a multidirectional sensitivity for the antennal-socket setae.

  12. Rhinoentomophthoromycosis: A rare case report

    Directory of Open Access Journals (Sweden)

    S Agrawal

    2013-01-01

    Full Text Available Entomophthoromycosis is chronic granulomatous fungal infection with varied presentation as subcutaneous,mucocutaneous and visceral infections. The majority of the subcutaneous infection caused by entomophthoralean fungi involves Basidiobolus spp, C. coronatus, or C. incongruous. A case of rhinoentomophthoromycosis in an immunocompetent male involving maxillary sinus and nose is presented. The patient was clinically diagnosed as malignancy of nose but microscopy and histopathology of the aspirate clinched the diagnosis. The patient responded to antifungal therepy.

  13. Macrodystrophia lipomatosa: four case reports

    Directory of Open Access Journals (Sweden)

    Ahmad Ibne

    2010-10-01

    Full Text Available Abstract Aim Macrodystrophia lipomatosa is a rare cause of gigantism of limb which can be confused with other common causes like congenital lymphedema. It presents usually with loss of function and cosmetic problems. Four cases are described with emphasis on clinical presentation, differential diagnoses, imaging and treatment options. Methods & Results Four patients of macrodystrophia lipomatosa were thoroughly examined and subjected to investigations. Conclusion Besides diligent clinical examination, imaging and histopathology are crucial in clinching the diagnosis.

  14. Does Domestic Service Require A College Education?

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A group of vocational college students recently came to Beijing to receive two months of hands-on work experience in domestic service. Dubbed "college-educated housemaids" by the media, their debut in the capital immediately created a sensation. A large number of Beijingers seeking household help went to interview them at a domestic service agency. Some clinched a deal after the first meeting. The students,

  15. Unconventional abdominal uses of FIESTA (CISS sequence

    Directory of Open Access Journals (Sweden)

    Anitha Sen

    2013-01-01

    Full Text Available The ability to provide cross-sectional imaging, combined with a lack of ionizing radiation has made magnetic resonance imaging (MRI of abdomen popular. We report four interesting cases: Midgut malrotation with volvulus, sigmoid volvulus, biliary rupture of hydatid cyst, and small bowel lipomatosis, where fast imaging employing steady-state acquisition [FIESTA]/constructive interference into steady state [CISS] sequence helped in clinching the diagnosis.

  16. Unconventional abdominal uses of FIESTA (CISS) sequence.

    Science.gov (United States)

    Sen, Anitha

    2013-10-01

    The ability to provide cross-sectional imaging, combined with a lack of ionizing radiation has made magnetic resonance imaging (MRI) of abdomen popular. We report four interesting cases: Midgut malrotation with volvulus, sigmoid volvulus, biliary rupture of hydatid cyst, and small bowel lipomatosis, where fast imaging employing steady-state acquisition [FIESTA]/constructive interference into steady state [CISS] sequence helped in clinching the diagnosis.

  17. Exploding the myths about the fast breeder reactor

    Energy Technology Data Exchange (ETDEWEB)

    Burns, S.

    1979-01-01

    This paper discusses the facts and figures about the effects of conservation policies, the benefits of the Clinch River Breeder Reactor demonstration plant, the feasibility of nuclear weapons manufacture from reactor-grade plutonium, diversion of plutonium from nuclear plants, radioactive waste disposal, and the toxicity of plutonium. The paper concludes that the U.S. is not proceeding with a high confidence strategy for breeder development because of a variety of false assumptions.

  18. Progeria syndrome with characteristic deformation of proximal radius observed on CT

    Energy Technology Data Exchange (ETDEWEB)

    Sood, S.; Rao, R.C.K.; Ragav, B.; Berry, M. (All India Inst. of Medical Sciences, New Delhi (India). Dept. of Radio-Diagnosis)

    1991-01-01

    The progeria syndrome (Hutchinson-Gilford) is an uncommon disease. A peculiar shape of the proximal radial metaphyseal region caused by an infolding of the cortex was observed on CT in 2 brothers suffering from this disorder, a feature not previously reported. A brief review of the radiologic literature was undertaken. This new observation needs to be further evaluated as it may provide a clinching diagnostic feature of this disease. (orig.).

  19. Radiological review of pleural tumors

    Directory of Open Access Journals (Sweden)

    Binit Sureka

    2013-01-01

    Full Text Available Tumors of the pleura are not uncommon and diagnosis is clinched by combined imaging and clinical correlation. Malignant tumors are more common than benign tumors. Initial imaging modalities are chest radiography and Computed Tomography (CT. Further characterization may be required using Ultrasoundgraphy (USG, Magnetic resonance Imaging (MRI and PET-CT. Biopsy remains gold standard. This article highlights various common and uncommon tumors of pleura and characteristic imaging findings.

  20. Seismic criteria studies and analyses. Quarterly progress report No. 3. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-03

    Information is presented concerning the extent to which vibratory motions at the subsurface foundation level might differ from motions at the ground surface and the effects of the various subsurface materials on the overall Clinch River Breeder Reactor site response; seismic analyses of LMFBR type reactors to establish analytical procedures for predicting structure stresses and deformations; and aspects of the current technology regarding the representation of energy losses in nuclear power plants as equivalent viscous damping.

  1. Uncovering ultrastructural defences in Daphnia magna--an interdisciplinary approach to assess the predator-induced fortification of the carapace.

    Directory of Open Access Journals (Sweden)

    Max Rabus

    Full Text Available The development of structural defences, such as the fortification of shells or exoskeletons, is a widespread strategy to reduce predator attack efficiency. In unpredictable environments these defences may be more pronounced in the presence of a predator. The cladoceran Daphnia magna (Crustacea: Branchiopoda: Cladocera has been shown to develop a bulky morphotype as an effective inducible morphological defence against the predatory tadpole shrimp Triops cancriformis (Crustacea: Branchiopoda: Notostraca. Mediated by kairomones, the daphnids express an increased body length, width and an elongated tail spine. Here we examined whether these large scale morphological defences are accompanied by additional ultrastructural defences, i.e. a fortification of the exoskeleton. We employed atomic force microscopy (AFM based nanoindentation experiments to assess the cuticle hardness along with tapping mode AFM imaging to visualise the surface morphology for predator exposed and non-predator exposed daphnids. We used semi-thin sections of the carapace to measure the cuticle thickness, and finally, we used fluorescence microscopy to analyse the diameter of the pillars connecting the two carapace layers. We found that D. magna indeed expresses ultrastructural defences against Triops predation. The cuticle in predator exposed individuals is approximately five times harder and two times thicker than in control daphnids. Moreover, the pillar diameter is significantly increased in predator exposed daphnids. These predator-cue induced changes in the carapace architecture should provide effective protection against being crushed by the predator's mouthparts and may add to the protective effect of bulkiness. This study highlights the potential of interdisciplinary studies to uncover new and relevant aspects even in extensively studied fields of research.

  2. Uncovering Ultrastructural Defences in Daphnia magna – An Interdisciplinary Approach to Assess the Predator-Induced Fortification of the Carapace

    Science.gov (United States)

    Rabus, Max; Söllradl, Thomas; Clausen-Schaumann, Hauke; Laforsch, Christian

    2013-01-01

    The development of structural defences, such as the fortification of shells or exoskeletons, is a widespread strategy to reduce predator attack efficiency. In unpredictable environments these defences may be more pronounced in the presence of a predator. The cladoceran Daphniamagna (Crustacea: Branchiopoda: Cladocera) has been shown to develop a bulky morphotype as an effective inducible morphological defence against the predatory tadpole shrimp Triopscancriformis (Crustacea: Branchiopoda: Notostraca). Mediated by kairomones, the daphnids express an increased body length, width and an elongated tail spine. Here we examined whether these large scale morphological defences are accompanied by additional ultrastructural defences, i.e. a fortification of the exoskeleton. We employed atomic force microscopy (AFM) based nanoindentation experiments to assess the cuticle hardness along with tapping mode AFM imaging to visualise the surface morphology for predator exposed and non-predator exposed daphnids. We used semi-thin sections of the carapace to measure the cuticle thickness, and finally, we used fluorescence microscopy to analyse the diameter of the pillars connecting the two carapace layers. We found that D. magna indeed expresses ultrastructural defences against Triops predation. The cuticle in predator exposed individuals is approximately five times harder and two times thicker than in control daphnids. Moreover, the pillar diameter is significantly increased in predator exposed daphnids. These predator-cue induced changes in the carapace architecture should provide effective protection against being crushed by the predator’s mouthparts and may add to the protective effect of bulkiness. This study highlights the potential of interdisciplinary studies to uncover new and relevant aspects even in extensively studied fields of research. PMID:23776711

  3. Uncovering ultrastructural defences in Daphnia magna--an interdisciplinary approach to assess the predator-induced fortification of the carapace.

    Science.gov (United States)

    Rabus, Max; Söllradl, Thomas; Clausen-Schaumann, Hauke; Laforsch, Christian

    2013-01-01

    The development of structural defences, such as the fortification of shells or exoskeletons, is a widespread strategy to reduce predator attack efficiency. In unpredictable environments these defences may be more pronounced in the presence of a predator. The cladoceran Daphnia magna (Crustacea: Branchiopoda: Cladocera) has been shown to develop a bulky morphotype as an effective inducible morphological defence against the predatory tadpole shrimp Triops cancriformis (Crustacea: Branchiopoda: Notostraca). Mediated by kairomones, the daphnids express an increased body length, width and an elongated tail spine. Here we examined whether these large scale morphological defences are accompanied by additional ultrastructural defences, i.e. a fortification of the exoskeleton. We employed atomic force microscopy (AFM) based nanoindentation experiments to assess the cuticle hardness along with tapping mode AFM imaging to visualise the surface morphology for predator exposed and non-predator exposed daphnids. We used semi-thin sections of the carapace to measure the cuticle thickness, and finally, we used fluorescence microscopy to analyse the diameter of the pillars connecting the two carapace layers. We found that D. magna indeed expresses ultrastructural defences against Triops predation. The cuticle in predator exposed individuals is approximately five times harder and two times thicker than in control daphnids. Moreover, the pillar diameter is significantly increased in predator exposed daphnids. These predator-cue induced changes in the carapace architecture should provide effective protection against being crushed by the predator's mouthparts and may add to the protective effect of bulkiness. This study highlights the potential of interdisciplinary studies to uncover new and relevant aspects even in extensively studied fields of research.

  4. Preliminary Evaluation of the Acute Toxicity of Desensitized Primer Compounds and Primer Waste Effluents to Representative Aquatic Organisims

    Science.gov (United States)

    1975-11-01

    daphnids, with 48-hour LC50 values for these two materials being several orders of magnitude lower than those observed for lead styphnate , PETN and... styphnate (PoTNR), tetracene (= tetrazene), pentaerythritol tetranitrate (PETN), .and FA 956 priming mixture. The FA 956 mixture is composed of: 37...PbTNR, 4% tetracene, 5% PETN, 32% barium nitrate, 15% antimony sulfide and 7% aluminum (Small and Rosenblatt, 1974). Each of these primer components was

  5. Remedial investigation/feasibility study report for Lower Watts Bar Reservoir Operable Unit

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    This document is the combined Remedial Investigation and Feasibility Study Report for the lower Watts Bar Reservoir (LWBR) Operable Unit (OU). The LWBR is located in Roane, Rhea, and Meigs counties, Tennessee, and consists of Watts Bar Reservoir downstream of the Clinch river. This area has received hazardous substances released over a period of 50 years from the US Department of Energy`s Oak Ridge Reservation (ORR), a National Priority List site established under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). As required by this law, the ORR and all off-site areas that have received contaminants, including LWBR, must be investigated to determine the risk to human health and the environment resulting from these releases, the need for any remedial action to reduce these risks, and the remedial actions that are most feasible for implementation in this OU. Contaminants from the ORR are primarily transported to the LWBR via the Clinch River. There is little data regarding the quantities of most contaminants potentially released from the ORR to the Clinch River, particularly for the early years of ORR operations. Estimates of the quantities released during this period are available for most radionuclides and some inorganic contaminants, indicating that releases 30 to 50 years ago were much higher than today. Since the early 1970s, the release of potential contaminants has been monitored for compliance with environmental law and reported in the annual environmental monitoring reports for the ORR.

  6. Phototransformation of Amlodipine in Aqueous Solution: Toxicity of the Drug and Its Photoproduct on Aquatic Organisms

    Directory of Open Access Journals (Sweden)

    Marina DellaGreca

    2007-01-01

    Full Text Available The phototransformation of amlodipine in water was investigated under various conditions. A quantum yield ΦS2.2×10−4 and a half-life time t1/2 0.419 days were calculated when the drug in water (10−4 M was exposed to sunlight. The only photoproduct found was its pyridine derivative. Formation of this product was explained on the basis of a radical cation intermediate. The acute and chronic toxicity of the drug and its photoproduct were evaluated on different organisms of the freshwater chain (Brachionus calyciflorus, Thamnocephalus platyurus, Daphnia magna, Ceriodaphnia dubia. The photoproduct exhibited a stronger toxic potential than the parent drug on the long time for C. dubia.

  7. Water quality assessment in piracicamirim creek upstream and downstream a sugar and ethanol industry through toxicity tests with cladocerans

    Directory of Open Access Journals (Sweden)

    Rafael Grossi Botelho

    2012-08-01

    Full Text Available An environmental impact study was conducted to determine the Piracicamirim's creek water quality in order to assess the influence of effluents from a sugar industry in this water body. For this, toxicity tests were performed with a water sample upstream and downstream the industry using the microcrustaceans Daphnia magna, Ceriodaphnia dubia and Ceriodaphnia silvestrii as test organisms, as well as physical and chemical analysis of water. Results showed that physical and chemical parameters did not change during the sampling period, except for the dissolved oxygen. No toxicity was observed for D. magna and reproduction of C. dubia and C. silvestrii in both sampling points. Thus, the industry was not negatively impacting the quality of this water body.

  8. Effect of metals on Daphnia magna and cladocerans representatives of the Argentinean fluvial littoral.

    Science.gov (United States)

    Luciana, Regaldo; Reno, Ulises; Gervasio, Susana; Horacio, Troiani; Gagneten, Ana María

    2014-07-01

    Chronic toxicity tests were conducted to assess the effect of Cu, Cr and Pb on Moinodaphnia macleayi and Ceriodaphnia dubia -two cladoceran species from the Argentinian Fluvial Littoral Zone (AFLZ)- and Daphnia magna -an holarctic species-. The specimens were exposed to three concentrations of each metal. As endpoints, the number of living and dead organisms, molts, neonates released, and the age of first reproduction were recorded. Chronic assays showed that Cu significantly affected the analyzed life history traits in the three species. The lowest Pb and Cr concentrations did not affect survival, molting or fecundity in D. magna. Conversely, in M. macleayi and C. dubia, survival, molting and fecundity showed highly significant differences in all the concentrations tested compared to control assay. The present study stresses the importance of using biological parameters as bioindicators, as well as the study species from the Southern Hemisphere to assess metal pollution.

  9. Toxicity of lithium to three freshwater organisms and the antagonistic effect of sodium.

    Science.gov (United States)

    Kszos, Lynn Adams; Beauchamp, John J; Stewart, Arthur J

    2003-10-01

    Lithium (Li) is the lightest metal and occurs primarily in stable minerals and salts. Concentrations of Li in surface water are typically toxicity of Li to common toxicity test organisms, we evaluated the toxicity of Li to Pimephales promelas (fathead minnow), Ceriodaphnia dubia, and a freshwater snail (Elimia clavaeformis). In the laboratory, the concentration of Li that inhibited P. promelas growth or C. dubia reproduction by 25% (IC25) was dependant upon the dilution water. In laboratory control water containing little sodium (approximately 2.8 mg l(-1)), the IC25s were 0.38 and 0.32 mg Li l(-1) and in ambient stream water containing approximately 17 mg Na l(-1), the IC25s were 1.99 and 3.33, respectively. A Li concentration of 0.15 mg l(-1) inhibited the feeding of E. clavaeformis in laboratory tests. Toxicity tests conducted to evaluate the effect of sodium on the toxicity of Li were conducted with fathead minnows and C. dubia. The presence of sodium greatly affected the toxicity of Li. Fathead minnows and Ceriodaphnia, for example, tolerated concentrations of Li as great as 6 mg l(-1) when sufficient Na was present. The interaction of Li and Na on the reproduction of Ceriodaphnia was investigated in depth and can be described using an exponential model. The model predicts that C. dubia reproduction would not be affected when animals are exposed to combinations of lithium and sodium with a log ratio of mmol Na to mmol Li equal to at least 1.63. The results of this study indicate that for most natural waters, the presence of sodium is sufficient to prevent Li toxicity. However, in areas of historical disposal or heavy processing or use, an evaluation of Li from a water quality perspective would be warranted.

  10. Toxicity of Trinitrotoluene to Sheepshead Minnows in Water Exposures

    Science.gov (United States)

    2010-02-06

    more toxic than TNT to an amphipod Hyalella azteca (2 times) and the cladoceran Ceriodaphia dubia (30 times) (Griest et al., 1998). Substantial...the aquatic amphipod Hyalella Azteca . Ecotoxicol. Environ. Saf. 70, 38–46. Smock, L.A., Stoneburner, D.L., Clark, J.R., 1976. The toxic effects of...tetranitro-1,3,5,7-tetrazocine in sediments to Chironomus tentans and Hyalella azteca : low-dose hormesis and high-dose mortality. Environ. Toxicol. Chem. 21

  11. Development of Environmental Health Criteria for Insensitive Munitions: Aquatic Ecotoxicological Exposures Using 2,4-Dinitroanisole

    Science.gov (United States)

    2013-03-01

    al. 2012). Acute toxicity testing Acute (48-hr) toxicity tests employed the larval fish Pimephales promelas and the water flea Ceriodaphnia dubia...NTO, CAS No. 932-64-9) - Acute toxicity to water fleas (Daphnia magna) under flow-through conditions, following OPPTS Draft Guideline 850.1010...environmental challenges. ERDC develops innovative solutions in civil and military engineering, geospatial sciences, water resources, and environmental

  12. Behaviour of ceria nanoparticles in standardized test media - influence on the results of ecotoxicological tests

    Energy Technology Data Exchange (ETDEWEB)

    Manier, Nicolas; Garaud, Mael; Delalain, Patrice; Aguerre-Chariol, Olivier; Pandard, Pascal, E-mail: nicolas.manier@ineris.fr [INERIS, Parc technologique ALATA, BP2, 60550 Verneuil en Halatte (France)

    2011-07-06

    The main objectives of this work were to establish the behaviour of a ceria nanopowder in different ecotoxicological media commonly used in standardized aquatic ecotoxicity tests and consequently to assess the acute and chronic ecotoxicity in two micro-invertebrates: Daphnia magna and Ceriodaphnia dubia and in a freshwater green algae: Pseudokirchneriella subcapitata. Different approaches to disperse the ceria nanoparticles (i.e. stirring, use of probe sonication, addition of humic acids) were tested and the influence on the biological endpoints was investigated. Despite the agglomeration phenomena observed in all the tested media, the results obtained indicated higher stability in the lower ionic strength media with addition of humic acid (2 mg.L{sup -1} TOC). No acute toxicity were observed with D. magna, whatever the dispersal method performed and the nCeO{sub 2} concentration tested (up to 1000 mg.L{sup -1}), as no acute toxicity was recorded with C. dubia following exposure to the stirring suspensions. On contrary, acute toxicity was recorded in C. dubia with EC{sub 50} values comprise between 11.9 and 25.3 mg.L{sup -1} using the probe sonicated suspension with or without humic acids addition. Significant chronic effect on the reproduction capability was also recorded in C. dubia. The estimated EC{sub 10} values were comprised between 2.1 and 2.9 mg.L{sup -1}. Focusing on P. subcapitata, despite the different agglomerate size recorded in the tested media at the end of the exposure periods, results obtained were similar. Adverse effect on algal growth around 5 mg.L{sup -1} were reported (mean EC{sub 10} = 4 {+-} 1.8 mg.L{sup -1}). Those results suggested the needed for standardized testing protocol concerning the aqueous media used or the sample preparation for laboratory testing.

  13. Comparative leaf anatomy in argentine Galactia species Anatomía comparada de hoja en especies argentinas de Galactia

    OpenAIRE

    G. M. Tourn; M. T. Cosa; G. G. Roitman; Silva,M.P.

    2009-01-01

    A comparative study of anatomical characters of the leaves of argentine species of Genera Galactia was carried out in order to evaluate their potential value in Taxonomy. In Argentine 14 species and some varieties from Sections Odonia and Collaearia can be found. Section Odonia: G. benthamiana Mich., G. dubia DC., G. fiebrigiana Burkart var. correntina Burkart, G. glaucophylla Harms, G. gracillima Benth., G. latisiliqua Desv., G. longifolia (Jacq.) Benth., G. marginalis Benth., G. striata (Ja...

  14. Vliv potravy na výši fertility u zákeřnic druhu \\kur{Platymeris biguttatus}

    OpenAIRE

    Zvonek, Dalibor

    2014-01-01

    This thesis was developed in order to determine whether the selected species most commonly kept feeding insects affect fertility in captive bred assassin bugs \\kur{Platymeris biguttatus}. Used feeding insects were \\kur{Blaptica dubia} roaches, \\kur{Acheta domestica} crickets and larvae of \\kur{Tenebrio molitor} bugs. The reason of using assassin bugs \\kur{Platymeris biguttatus} was their popularity among breeders, their easy care needs and their superior fertility. Assassin bugs were kept in ...

  15. Recognition of inconspicuous prey: importance of additional visual cues

    OpenAIRE

    KARLÍKOVÁ, Zuzana

    2012-01-01

    The ability of wild caught great tits (Parus major) to discriminate between equally coloured edible (roach - Blaptica dubia) and inedible prey (firebug - Pyrrhocoris apterus) was tested with respect to other visual traits (shape of legs, antennae,means of locomotion). To simulate more natural conditions, three different experiment types were carried out. Prey was presented either alternately (first roach or firebug) or simultaneously. Additionally, the effect of learning and memory was tested...

  16. Scientific heritage of Alexandru Roşca: publications, spider collection, described species

    Directory of Open Access Journals (Sweden)

    Fedoriak, Mariia

    2016-04-01

    During the period 1931–1939, Roşca described 13 spider species. To date, five species names have been synonymised. We propose that six species should be treated as nomina dubia because of their poor descriptions and lack of availability of types and/or other specimens. For two of Roşca’s species, Pardosa roscai (Roewer, 1951 and Tetragnatha reimoseri (Roşca, 1939, data and figures are presented and information on them is updated.

  17. Aquatic Plant Control Research Program: Effects of Submersed Aquatic Macrophytes on Physical and Chemical Properties of Surrounding Water

    Science.gov (United States)

    1988-12-01

    period. Potamogeton foliosus Raf., Potamogeton pectinatus L., Heteranthera dubia (Jacquin) MacM., Najas flexilis (Willd.) Rostk. & Schmidt, and Elodea ...by Gons (1982) and in dense Elodea stands in a Colorado alpine lake by Buscemi (1958). Actual mechanisms by which these profiles occur are not...by a cover of Elodea canadensis. Oikos 9:239-245. Carpenter, S. R. 1980. Enrichment of Lake Wingra, Wisconsin, by submersed macrophyte decay. Ecology

  18. Comparative leaf anatomy in argentine Galactia species Anatomía comparada de hoja en especies argentinas de Galactia

    OpenAIRE

    Tourn, G.M.; M. T. Cosa; G. G. Roitman; Silva,M.P.

    2009-01-01

    A comparative study of anatomical characters of the leaves of argentine species of Genera Galactia was carried out in order to evaluate their potential value in Taxonomy. In Argentine 14 species and some varieties from Sections Odonia and Collaearia can be found. Section Odonia: G. benthamiana Mich., G. dubia DC., G. fiebrigiana Burkart var. correntina Burkart, G. glaucophylla Harms, G. gracillima Benth., G. latisiliqua Desv., G. longifolia (Jacq.) Benth., G. marginalis Benth., G. striata (Ja...

  19. Toxicity of benzotriazole and benzotriazole derivatives to three aquatic species.

    Science.gov (United States)

    Pillard, D A; Cornell, J S; Dufresne, D L; Hernandez, M T

    2001-02-01

    Benzotriazole and its derivatives comprise an important class of corrosion inhibitors, typically used as trace additives in industrial chemical mixtures such as coolants, deicers, surface coatings, cutting fluids, and hydraulic fluids. Recent studies have shown that benzotriazole derivatives are a major component of aircraft deicing fluids (ADFs) responsible for toxicity to bacteria (Microtox). Our current research compared the toxicity of benzotriazole (BT), two methylbenzotriazole (MeBT) isomers, and butylbenzotriazole (BBT). Acute toxicity assays were used to model the response of three common test organisms: Microtox bacteria (Vibrio fischeri), fathead minnow (Pimephales promelas) and water flea (Ceriodaphnia dubia). The response of all the three organisms varied over two orders of magnitude among all compounds. Vibrio fischeri was more sensitive than either C. dubia or P. promelas to all the test materials, while C. dubia was less sensitive than P. promelas. The response of test organisms to unmethylated benzotriazole and 4-methylbenzotriazole was similar, whereas 5-methylbenzotriazole was more toxic than either of these two compounds. BBT was the most toxic benzotriazole derivative tested, inducing acute toxicity at a concentration of < or = 3.3 mg/l to all organisms.

  20. Soil bioretention protects juvenile salmon and their prey from the toxic impacts of urban stormwater runoff.

    Science.gov (United States)

    McIntyre, J K; Davis, J W; Hinman, C; Macneale, K H; Anulacion, B F; Scholz, N L; Stark, J D

    2015-08-01

    Green stormwater infrastructure (GSI), or low impact development, encompasses a diverse and expanding portfolio of strategies to reduce the impacts of stormwater runoff on natural systems. Benchmarks for GSI success are usually framed in terms of hydrology and water chemistry, with reduced flow and loadings of toxic chemical contaminants as primary metrics. Despite the central goal of protecting aquatic species abundance and diversity, the effectiveness of GSI treatments in maintaining diverse assemblages of sensitive aquatic taxa has not been widely evaluated. In the present study we characterized the baseline toxicity of untreated urban runoff from a highway in Seattle, WA, across six storm events. For all storms, first flush runoff was toxic to the daphniid Ceriodaphnia dubia, causing up to 100% mortality or impairing reproduction among survivors. We then evaluated whether soil media used in bioretention, a conventional GSI method, could reduce or eliminate toxicity to juvenile coho salmon (Oncorhynchus kisutch) as well as their macroinvertebrate prey, including cultured C. dubia and wild-collected mayfly nymphs (Baetis spp.). Untreated highway runoff was generally lethal to salmon and invertebrates, and this acute mortality was eliminated when the runoff was filtered through soil media in bioretention columns. Soil treatment also protected against sublethal reproductive toxicity in C. dubia. Thus, a relatively inexpensive GSI technology can be highly effective at reversing the acutely lethal and sublethal effects of urban runoff on multiple aquatic species.

  1. Chemical and toxicological characterization of slurry reactor biotreatment of explosives-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Griest, W.H.; Stewart, A.J.; Vass, A.A.; Ho, C.H.

    1998-08-01

    Treatment of 2,4,6-trinitrotoluene (TNT)-contaminated soil in the Joliet Army Ammunition Plant (JAAP) soil slurry bioreactor (SSBR) eliminated detectable TNT but left trace levels of residual monoamino and diamino metabolites under some reactor operating conditions. The reduction of solvent-extractable bacterial mutagenicity in the TNT-contaminated soil was substantial and was similar to that achieved by static pile composts at the Umatilla Army Depot Activity (UMDA) field demonstration. Aquatic toxicity to Ceriodaphnia dubia from TNT in the leachates of TNT-contaminated soil was eliminated in the leachates of JAAP SSBR product soil. The toxicity of soil product leachates to Ceriodaphnia dubia was reasonably predicted using the specific toxicities of the components detected, weighted by their leachate concentrations. In samples where TNT metabolites were observed in the soil product and its leachates, this method determined that the contribution to predicted toxicity values was dominated by trace amounts of the diamino-metabolites, which are very toxic to ceriodaphnia dubia. When the SSBR operating conditions reduced the concentrations of TNT metabolites in the product soils and their leachates to undetectable concentrations, the main contributors to predicted aquatic toxicity values appeared to be molasses residues, potassium, and bicarbonate. Potassium and bicarbonate are beneficial or benign to the environment, and molasses residues are substantially degraded in the environment. Exotoxins, pathogenic bacteria, inorganic particles, ammonia, and dissolved metals did not appear to be important to soil product toxicity.

  2. Life history and propagation of the endangered dromedary pearlymussel (Dromus dromas) (Bivalvia:Unionidae)

    Science.gov (United States)

    Jones, J.W.; Neves, R.J.; Ahlstedt, S.A.; Mair, R.A.

    2004-01-01

    The reproduction, demography, and propagation of the endangered dromedary pearlymussel (Dromus dromas) (Lea, 1834) were studied in the Clinch and Powell rivers, Tennessee. Viable populations of the dromedary pearlymussel now occur only in the Clinch and Powell rivers; the species has been extirpated from the remaining portions of its range in the Cumberland and Tennessee river drainages. Females are long-term winter brooders, and they are gravid from October to June. Glochidia are contained in conglutinates that are red to white and resemble freshwater leeches or flatworms. Conglutinates are 20 to 40 mm long and are released through the excurrent aperture. Estimates of fecundity based on 7 gravid females collected from the Clinch River were 55,110 to 253,050 glochidia/mussel. The ages of 66 valves of D. dromas were determined by thin-sectioning and ranged from 3 to 25 y. Annual growth averaged 5 mm/y until age 10 and decreased to ???1.2 mm/ y thereafter. Nineteen fish species were tested for suitability as hosts for glochidia. Ten were confirmed as hosts through induced infestations of glochidia: black sculpin (Cottus baileyi), greenside darter (Etheostoma blennioides), fantail darter (Etheostoma flabellare), snubnose darter (Etheostoma simoterum), tangerine darter (Percina aurantiaca), blotchside logperch (Percina burtoni), logperch (Percina caprodes), channel darter (Percina copelandi), gilt darter (Percina evides), and Roanoke darter (Percina roanoka). Juveniles produced from these hosts were cultured in dishes held in nonrecirculating aquaculture systems containing fine sediment (<105 ??m) and were fed the green alga Nannochloropsis oculata every 2 d. Survival of 2810 newly metamorphosed juveniles was 836 (29.7%) after 1 to 2 wk.

  3. Motor actions and spatiotemporal changes by weight divisions of mixed martial arts: Applications for training.

    Science.gov (United States)

    Miarka, Bianca; Brito, Ciro José; Bello, Fábio Dal; Amtmann, John

    2017-10-01

    This study compared motor actions and spatiotemporal changes between weight divisions from Ultimate Fighting Championship (UFC™), conducting a practical application for mixed martial arts (MMA) training. For this, we analyzed 2814 rounds of all weight divisions by motor actions and spatiotemporal changes according actions and time of the Keeping distance, Clinch and Groundwork combat phases. We observed differences between weight divisions in the keeping distance on stand-up combat (p≤0.001; with lower time in Featherweight 131.4s and bantamweight 127.9s) clinch without attack (p≤0.001; with higher timer in Flyweight 11.4s and Half-middleweight 12.6s) and groundwork without attack (p≤0.001; with higher timer in Half-middleweight 0.9s). During keeping distance, half-middleweight presented a higher frequency of Head Strikes Landed (p=0.026; 7±8 times) and attempted (p=0.003; 24±22 times). In clinch actions heavyweight present a higher frequency (p≤0.023) of head strike landed (3±7 times) and attempted (4±9 times) and half-middleweight for body strikes (p≤0.023) landed (2±5 times) and attempted (3±5 times). At the last, during groundwork, Bantamweight present a higher frequency (p≤0.036) of head strikes landed (8±10 times) and attempted (10±13 times) body strikes landed (p≤0.044; 3±5 times) and attempted (3±6 times). This study reveals important point to training and provide a challenge applied referential to the conditioning plains. From the weight divisions differences should be aware of the increase in the frequency of distance actions, especially in light and middleweights. On the Ground, bantamweight can focus on striking and grappling actions than others. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Comparison of Toxicity of Sediments from Rivers with Different Levels of Anthropogenic Load (Middle Volga Region, Russia Based on Elutriate and Whole Sediment Tests

    Directory of Open Access Journals (Sweden)

    N.Yu. Stepanova

    2016-09-01

    Full Text Available Description of chemical characteristics and toxicity testing of whole sediment and elutri-ate have been performed with 35 samples taken during the monitoring of rivers in the Middle Volga region (Tatarstan, Russia in 2013. The locations analyzed are sites associated with agriculture, forestry, and petroleum hydrocarbons (oil production. The toxicity tests include: (1 Chlorella vulgaris (algal elutriate test, (2 Paramecium caudatum (ciliate elutriate test, (3 Daphnia magna (cladoceran whole sediment toxicity test, and (4 Heterocypris incongruens (ostracod whole sediment toxicity test. The concentrations of metals in 43% of sediment samples have been found to exceed probable effect concentration sediment quality guidelines (SQGs. However, the concentrations of polycyclic aromatic hydrocarbons (PAHs and organochlorine pesticides have turned out to be below SQGs in most sites. The correlation analysis has shown metal toxicity to daphnid reproduction and ostracod growth (R2 = 0.34–0.64 and ammonia (R2 = 0.49–0.54. A higher percentage of samples have shown toxicity in the whole sediment tests (86% compared to the elutriate tests (54%. A total of 91% of samples have demonstrated toxicity for at least one species. Toxicity has been most frequently observed for daphnid reproduction (83% of samples and ostracod growth (56% of samples compared to daphnid (23% survival, ostracod (11% survival, and ciliate reproduction (54% or algal growth (54%. The most polluted sediments have been registered in the area of oil production. The comparison of toxicity of the samples from different types of areas has indicated that 100% of samples from the oil production area, 94% of samples from the agricultural area, and 50% of samples from the forest area were toxic to at least one test organism.

  5. NMDA receptor activation upstream of methyl farnesoate signaling for short day-induced male offspring production in the water flea, Daphnia pulex.

    Science.gov (United States)

    Toyota, Kenji; Miyakawa, Hitoshi; Yamaguchi, Katsushi; Shigenobu, Shuji; Ogino, Yukiko; Tatarazako, Norihisa; Miyagawa, Shinichi; Iguchi, Taisen

    2015-03-14

    The cladoceran crustacean Daphnia pulex produces female offspring by parthenogenesis under favorable conditions, but in response to various unfavorable external stimuli, it produces male offspring (environmental sex determination: ESD). We recently established an innovative system for ESD studies using D. pulex WTN6 strain, in which the sex of the offspring can be controlled simply by changes in the photoperiod: the long-day and short-day conditions can induce female and male offspring, respectively. Taking advantage of this system, we demonstrated that de novo methyl farnesoate (MF) synthesis is necessary for male offspring production. These results indicate the key role of innate MF signaling as a conductor between external environmental stimuli and the endogenous male developmental pathway. Despite these findings, the molecular mechanisms underlying up- and downstream signaling of MF have not yet been well elucidated in D. pulex. To elucidate up- and downstream events of MF signaling during sex determination processes, we compared the transcriptomes of daphnids reared under the long-day (female) condition with short-day (male) and MF-treated (male) conditions. We found that genes involved in ionotropic glutamate receptors, known to mediate the vast majority of excitatory neurotransmitting processes in various organisms, were significantly activated in daphnids by the short-day condition but not by MF treatment. Administration of specific agonists and antagonists, especially for the N-methyl-D-aspartic acid (NMDA) receptor, strongly increased or decreased, respectively, the proportion of male-producing mothers. Moreover, we also identified genes responsible for male production (e.g., protein kinase C pathway-related genes). Such genes were generally shared between the short-day reared and MF-treated daphnids. We identified several candidate genes regulating ESD which strongly suggests that these genes may be essential factors for male offspring production as an

  6. A strategy to reduce the numbers of fish used in acute ecotoxicity testing of pharmaceuticals.

    Science.gov (United States)

    Hutchinson, Thomas H; Barrett, Sarah; Buzby, Mary; Constable, David; Hartmann, Andreas; Hayes, Eileen; Huggett, Duane; Laenge, Reinhard; Lillicrap, Adam D; Straub, Jürg Oliver; Thompson, Roy S

    2003-12-01

    The pharmaceutical industry gives high priority to animal welfare in the process of drug discovery and safety assessment. In the context of environmental assessments of active pharmaceutical ingredients (APIs), existing U.S. Food and Drug Administration and draft European regulations may require testing of APIs for acute ecotoxicity to algae, daphnids, and fish (base-set ecotoxicity data used to derive the predicted no-effect concentration [PNECwater] from the most sensitive of three species). Subject to regulatory approval, it is proposed that testing can be moved from fish median lethal concentration (LC50) testing (typically using > or = 42 fish/API) to acute threshold tests using fewer fish (typically 10 fish/API). To support this strategy, we have collated base-set ecotoxicity data from regulatory studies of 91 APIs (names coded for commercial reasons). For 73 of the 91 APIs, the algal median effect concentration (EC50) and daphnid EC50 values were lower than or equal to the fish LC50 data. Thus, for approximately 80% of these APIs, algal and daphnid acute EC50 data could have been used in the absence of fish LC50 data to derive PNECwater values. For the other 18 APIs, use of an acute threshold test with a step-down factor of 3.2 is predicted to give comparable PNECwater outcomes. Based on this preliminary scenario of 91 APIs, this approach is predicted to reduce the total number of fish used from 3,822 to 1,025 (approximately 73%). The present study, although preliminary, suggests that the current regulatory requirement for fish LC50 data regarding APIs should be succeeded by fish acute threshold (step-down) test data, thereby achieving significant animal welfare benefits with no loss of data for PNECwater estimates.

  7. To flee or not to flee: detection, avoidance and attraction of profitable resources by Daphnia magna studied with olfactometer

    Directory of Open Access Journals (Sweden)

    Johann P. Müller

    2013-10-01

    Full Text Available The cladoceran herbivore Daphnia magna is a major consumer of phytoplankton in lakes. Therefore, this organism may control the phytoplankton community and the proliferation of some algae or cyanobacteria. Cladoceran behaviour and migration in relation to temperature, light or presence of planktivorous fishes have been well studied. In particular, it is known that the detection of kairomones produced by predators may induce avoidance. Avoidance could also occur with other semiochemicals such as cyanotoxins. In order to explore this hypothesis, we used an olfactometer to observe and measure the exploratory behaviour of D. magna individuals based on the motivation for food. Daphnids were allowed to choose between different compounds: water, a pure cyanotoxin, i.e. the microcystin-RR [(MC-RR], extracts of one MC-producing strain (PMC 75.02 and one MC-free strain (PMC 87.02 of Planktothrix agardhii, or a green algae Scenedesmus obliquus. With this experimental design, we observed that i cladocerans are able to detect resources with different qualities, ii they can explore before exhibiting preferences, and iii daphnids are able to avoid compounds that are potentially toxic (e.g., microcystins. First, daphnids explored the environment, subsequently (after about 1.5 h, they showed a significant tendency to stay where there is a profitable resource such as S. obliquus. These results also suggest that specimens of D. magna cannot detect MC compounds from P. agardhii, but they respond to it as a food resource. The study of zooplankton ability to explore the environment when exposed to semiochemicals needs further investigation. 

  8. Effects of ectoine on behavioural, physiological and biochemical parameters of Daphnia magna.

    Science.gov (United States)

    Bownik, Adam; Stępniewska, Zofia; Skowroński, Tadeusz

    2015-02-01

    Ectoine (ECT) is a compatible solute produced by soil, marine and freshwater bacteria in response to stressful factors. The purpose of our study was to determine the possible toxic influence of ECT on Daphnia magna. We determined the following endpoints: survival rate during exposure and recovery, swimming performance, heart rate, thoracic limb movement determined by image analysis, haemoglobin level by ELISA assay, catalase and nitric oxide species (NOx) by spectrophotometric methods. The results showed 80% survival of daphnids exposed to 50mg/L of ECT after 24h and 10% after 90h, however lower concentrations of ECT were well tolerated. A concentration-dependent reduction of swimming velocity was noted at 24 and 48h of the exposure. ECT (at 2.5 and 4mg/L) induced an increase of heart rate and thoracic limb movement (at 2.5, 4 and 20mg/L) after 24h. After 10h of the exposure to ECT daphnids showed a concentration-dependent increase of haemoglobin level synthesized and accumulated in the epipodite epithelia. After 24h we noted a concentration-dependent decrease of haemoglobin level and its lowest value was found after 48h of the exposure. ECT at a concentration of 20 and 25mg/L slightly stimulated catalase activity after 24h. NOx level was also increased after 10h of the exposure to 20 and 25mg/L of ECT reaching maximal activity after 24h. Our results suggest that ECT possesses some modulatory potential on the behaviour, physiology and biochemical parameters in daphnids.

  9. Rubinstein-Taybi syndrome with agenesis of corpus callosum.

    Science.gov (United States)

    Mishra, Shubhankar; Agarwalla, Sunil Kumar; Potpalle, Dnyaneshwar Ramesh; Dash, Nishant Nilotpal

    2015-01-01

    Rubinstein-Taybi syndrome (RSTS) is a rare genetic disorder with characteristic morphological anomaly. Our patient was a 4.5-year-old girl came with features like broad thumbs, downward slanting palpebral fissures and mental retardation. Systemic abnormalities such as repeated infection, seizure with developmental delay were also associated with it. She was having head banging behavior abnormal slurring speech, incoordination while transferring things from one hand to other. Galaxy of clinical pictures and magnetic resonance imaging report helped to clinch the diagnosis as a case of "RSTS with corpus callosal agenesis" which to the best of our knowledge has never been reported in past from India.

  10. Rubinstein-Taybi syndrome with agenesis of corpus callosum

    Directory of Open Access Journals (Sweden)

    Shubhankar Mishra

    2015-01-01

    Full Text Available Rubinstein-Taybi syndrome (RSTS is a rare genetic disorder with characteristic morphological anomaly. Our patient was a 4.5-year-old girl came with features like broad thumbs, downward slanting palpebral fissures and mental retardation. Systemic abnormalities such as repeated infection, seizure with developmental delay were also associated with it. She was having head banging behavior abnormal slurring speech, incoordination while transferring things from one hand to other. Galaxy of clinical pictures and magnetic resonance imaging report helped to clinch the diagnosis as a case of "RSTS with corpus callosal agenesis" which to the best of our knowledge has never been reported in past from India.

  11. U.S. Department of Energy & Nuclear Regulatory Commission Advanced Fuel Cycle Research & Development Seminar Series FY 2007 & 2008

    Energy Technology Data Exchange (ETDEWEB)

    Grandy, Christopher [Argonne National Lab. (ANL), Argonne, IL (United States)

    2008-08-01

    In fiscal year 2007, the Advanced Burner Reactor project initiated an educational seminar series for the Department of Energy (DOE) and Nuclear Regulatory Commission (NRC) personnel on various aspects of fast reactor fuel cycle closure technologies. This important work was initiated to inform DOE and NRC personnel on initial details of sodium-cooled fast reactor, separations, waste form, and safeguard technologies being considered for the Advanced Fuel Cycle Research and Development program, and to learn the important lesson from the licensing process for the Clinch River Breeder Reactor Plant that educating the NRC staff early in the regulatory process is very important and critical to a project success.

  12. The great carve up continues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-24

    Enel's success in Spain looks suspiciously like the second phase in an Italo-Spanish asset swap. But swaps are notoriously hard to broker, especially when they involve physical assets of varying age and quality in diverse markets. At first sight, Enel would appear to have clinched a rather good deal in 'new Viesgo', while Endesa certainly paid top dollar for Elettrogen. The article discusses these recent events with experts in the field. A table shows Viesgo's generation assets and another gives facts on European plant sales, by fuel type. 2 tabs.

  13. Congenital Chikungunya with Centro-facial Pigmentation and Persistent Thrombocytopenia: A Case Report

    Directory of Open Access Journals (Sweden)

    Shilpa Kalane

    2015-05-01

    Full Text Available Hyperpigmentation over face in a neonate is rare and the differentials for the same are also rare. Congenital chickengunya, fungal and viral infections, drug rash are few differentials. Chikungunya virus (CHIKV infection manifesting in neonates is very rare. The prevalence of the entity was described only recently. We describe a neonate with hyperpigmentation on day 3 of life with stormy course thereafter. The distinguishing rash on face helped us in clinching the diagnosis of congenital chikungunya and fungal sepsis. Identification of this entity was based on characteristic skin rash and epidemiological background.

  14. カナダラブラドル地方、ネーン岩体の地質:最古の海洋地殻の発見に向け

    OpenAIRE

    小宮剛; Tsuyoshi Komiya; 下條将徳; 澤木佑介; Yusuke Sawaki; 山本伸次; shinji yamamoto; 石川晃; 青木一勝; Kazumasa Aoki

    2012-01-01

    The Hadean is the most mysterious period because no rocks and geologic bodies are preserved except for only the zircons inWestern Australia, Canada, China and Greenland (Froude et al., 1983, Nature; Nelson et al., 2000, EPSL; Mojzsis & Harrison,2002 EPSL; Iizuka et al., 2006, Geology;Wang et al., 2007, CSB). But, it is the most important period because the early evolutionpossibly clinched the history of the earth. We try to find the earliest supracrustal rocks in the world to investigate the ...

  15. SUBACUTE SCLEROSING PANENCEPHALITIS: A RARE NEUROLOGICAL DISORDER IN PREGNANCY

    Directory of Open Access Journals (Sweden)

    Minakeshi

    2015-03-01

    Full Text Available Subacute Sclerosing Panencephalitis ( SSPE is a rare, chronic progressive demyelinating disease. Incidence of subacute sclerosing panencephalitis has declined after vaccination but annual incidence is quite high and in India its Incidence is 21 per million population. We had a case of term pregnancy with a history of forgetfulness, abnormal behaviour, abnormal movement of body and altered sensorium. Detailed history, neurologic examination, serology ( CSF & serum and MRI brain clinched the diagnosis. Patient under w ent LSCS for fetal distress. She was put on trial of interferon - alpha 2b but she developed superadded infection and died.

  16. Consolidation in a child from tuberculosis endemic area - thinking apart from tuberculosis

    Directory of Open Access Journals (Sweden)

    George P Jacob

    2013-01-01

    Full Text Available Tuberculosis is endemic in South East Asian regions and hence a disease commonly over diagnosed in these parts of the country. Patients presenting with chest x ray shadows and vague symptoms are often started on Anti Tuberculosis Treatment - smear negative. However caution should be administered in prescribing ATT to patients who do not improve symptomatically, even after intensive phase. Congenital abnormalities such as sequestrated lung at times can also be rare causes of abnormal skiagram chest, especially in paediatric patients. A careful systematic approach with non invasive imaging such as CECT chest will often help to clinch the diagnosis in most cases.

  17. Large scale breeder reactor plant prototype mechanical pump conceptual design study

    Energy Technology Data Exchange (ETDEWEB)

    1976-07-01

    This final report is a complete conceptual design study of a mechanical pump for a large scale breeder reactor plant. The pumps are located in the cold leg side of the loops. This makes the net positive suction head available - NPSHA - low, and is, in fact, a major influencing factor in the design. Where possible, experience gained from the Clinch River Project and the FFTF is used in this study. Experience gained in the design, manufacturer, and testing of pumps in general and sodium pumps in particular is reflected in this report. The report includes estimated cost and time schedule for design, manufacture, and testing. It also includes a recommendation for development needs.

  18. Specification for reliability data management system

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-09-24

    This document contains the objectives, scopes, a brief delineation of the design, performance, and definition of the Reliability Data Management System (RDMS). The General Electric Company - Fast Breeder Reactor Department (GE-FBRD) has responsibility for the design and implementation of a Reliability Data Management System (RDMS). This document describes and specifies the RDMS requirements. The RDMS is currently focused on obtaining data for the Clinch River Breeder Reactor Plant (CRBRP) Shutdown System and Shutdown Heat Removal System, but has been designed with capability and flexibility for accommodating additional CRBRP and Liquid Metal Fast Breeder Reactor (LMFBR) reliability data.

  19. Breeder Spent Fuel Handling (BSFH) cask study for FY83. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Diggs, J M

    1985-01-01

    This report documents a study conducted to investigate the applicability of existing LWR casks to shipment of long-cooled LMFBR fuel from the Clinch River Breeder Reactor Plant (CRBRP) to the Breeder Reprocessing Engineering Test (BRET) Facility. This study considered a base case of physical constraints of plants and casks, handling capabilities of plants, through-put requirements, shielding requirements due to transportation regulation, and heat transfer capabilities of the cask designs. Each cask design was measured relative to the base case. 15 references, 4 figures, 6 tables.

  20. Design data and safety features of commerical nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Heddleson, F.A.

    1976-06-01

    Design data, safety features, and site characteristics are summarized for 34 nuclear power units in 17 power stations in the United States. Six pages of data are presented for each plant, consisting of thermal-hydraulic and nuclear factors, containment features, emergency-core-cooling systems, site features, circulating water system data, and miscellaneous factors. An aerial perspective is also presented for each plant. This volume covers Light Water Reactors (LWRs) with dockets 50-508 through 50-549, four HTGRs--50-171, 50-267, 50-450/451, 50-463/464, the Atlantic Floating Station 50-477/478, and the Clinch River Breeder 50-537.

  1. Acute silver toxicity in aquatic animals is a function of sodium uptake rate

    DEFF Research Database (Denmark)

    Bianchini, A.; Grosell, Martin Hautopp; Gregory, S.

    2002-01-01

    -specific surface area of the gills depends on animal body mass; and (iv) the gill surface is also the major site of Na+ loss by diffusion, we hypothesized that whole body Na+ uptake rate (i.e., turnover rate) and secondarily body mass would be good predictors of acute silver toxicity. Results obtained from...... toxicological (LC50 of AgNO3) and physiological (22Na uptake rate) tests performed on juvenile fish (rainbow trout, Oncorhynchus mykiss), early juvenile and adult crayfish (Cambarus diogenes diogenes), and neonate and adult daphnids (Daphnia magna) in moderately hard water of constant quality support the above...

  2. Recommendations on the proposed Monitored Retrievable Storage Facility

    Energy Technology Data Exchange (ETDEWEB)

    1985-10-01

    Following the Department of Energy`s announcement in April 1985 that three Tennessee sites were to be considered for the Monitored Retrievable Storage facility, Governor Lamar Alexander initiated a review of the proposal to be coordinated by his Safe Growth Team. Roane County and the City of Oak Ridge, the local governments sharing jurisdiction over DOE`s primary and secondary sites, were invited to participate in the state`s review of the MRS proposal. Many issues related to the proposed MRS are being considered by the Governor`s Safe Growth Team. The primary objective of the Clinch River MRS Task Force has been to determine whether the proposed Monitored Retrievable Storage facility should be accepted by the local governments, and if so, under what conditions. The Clinch River MRS Task Force is organized into an Executive Committee cochaired by the Roane County Executive and Mayor of Oak Ridge and three Study Groups focusing on environmental (including health and safety), socioeconomic, and transportation issues.

  3. Recommendations on the proposed Monitored Retrievable Storage Facility

    Energy Technology Data Exchange (ETDEWEB)

    1985-10-01

    Following the Department of Energy's announcement in April 1985 that three Tennessee sites were to be considered for the Monitored Retrievable Storage facility, Governor Lamar Alexander initiated a review of the proposal to be coordinated by his Safe Growth Team. Roane County and the City of Oak Ridge, the local governments sharing jurisdiction over DOE's primary and secondary sites, were invited to participate in the state's review of the MRS proposal. Many issues related to the proposed MRS are being considered by the Governor's Safe Growth Team. The primary objective of the Clinch River MRS Task Force has been to determine whether the proposed Monitored Retrievable Storage facility should be accepted by the local governments, and if so, under what conditions. The Clinch River MRS Task Force is organized into an Executive Committee cochaired by the Roane County Executive and Mayor of Oak Ridge and three Study Groups focusing on environmental (including health and safety), socioeconomic, and transportation issues.

  4. Flow Induced Vibration Program at Argonne National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1984-01-01

    Argonne National Laboratory has had a Flow Induced Vibration Program since 1967; the Program currently resides in the Laboratory's Components Technology Division. Throughout its existence, the overall objective of the program has been to develop and apply new and/or improved methods of analysis and testing for the design evaluation of nuclear reactor plant components and heat exchange equipment from the standpoint of flow induced vibration. Historically, the majority of the program activities have been funded by the US Atomic Energy Commission (AEC), Energy Research and Development Administration (ERDA), and Department of Energy (DOE). Current DOE funding is from the Breeder Mechanical Component Development Division, Office of Breeder Technology Projects; Energy Conversion and Utilization Technology (ECUT) Program, Office of Energy Systems Research; and Division of Engineering, Mathematical and Geosciences, Office of Basic Energy Sciences. Testing of Clinch River Breeder Reactor upper plenum components has been funded by the Clinch River Breeder Reactor Plant (CRBRP) Project Office. Work has also been performed under contract with Foster Wheeler, General Electric, Duke Power Company, US Nuclear Regulatory Commission, and Westinghouse.

  5. The development of an aquatic spill model for the White Oak Creek watershed, Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.O.

    1996-05-01

    This study develops an aquatic spill model applicable to the White Oak Creek watershed draining the Oak Ridge National Laboratory. Hazardous, toxic, and radioactive chemicals are handled and stored on the laboratory reservation. An accidental spill into the White Oak Creek watershed could contaminate downstream water supplies if insufficient dilution did not occur. White Oak Creek empties into the Clinch River, which flows into the Tennessee River. Both rivers serve as municipal water supplies. The aquatic spill model provides estimates of the dilution at sequential downstream locations along White Oak creek and the Clinch River after an accidental spill of a liquid containing a radioactively decaying constituent. The location of the spill on the laboratory is arbitrary, while hydrologic conditions range from drought to extreme flood are simulated. The aquatic spill model provides quantitative estimates with which to assess water quality downstream from the site of the accidental spill, allowing an informed decision to be made whether to perform mitigating measures so that the integrity of affected water supplies is not jeopardized.

  6. First annual report on the Biological Monitoring and Abatement Program at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J. M. [ed.; Adams, S. M.; Blaylock, B. G.; Boston, H. L.; Frank, M. L.; Garten, C. T.; Houston, M. A.; Kimmel, B. L.; Ryon, M. G.; Smith, J. G.; Southworth, G. R.; Stewart, A. J.; Walton, B. T.; Berry, J. B.; Talmage, S. S. [Oak Ridge National Lab., TN (United States); Amano, H. [JAERI, Tokai Res., Establishment, Ibari-Ken (Japan); Jimenez, B. D. [School of Pharmacy, Univ. of Puerto Rico (San Juan); Kitchings, J. T. [ERCE, Denver, CO (United States); Meyers-Schoene, L. [Advanced Sciences, Inc., Fernald, OH (United States); Mohrbacher, D. A. [Univ. of Tennessee, Knoxville, TN (United States); Olsen, C. R. [USDOE Office of Energy Research, Washington, DC (United States). Office of Health and Environmental Research

    1992-08-01

    As a condition of the National Pollutant Discharge Elimination System (NPDES) permit issued to Oak Ridge National Laboratory (ORNL) on April 1, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for White Oak Creek (WOC); selected tributaries of WOC, including Fifth Creek, First Creek, Melton Branch, and Northwest Tributary; and the Clinch River. BMAP consists of seven major tasks that address both radiological and nonradiological contaminants in the aquatic and terrestrial environs on-site and the aquatic environs off-site. These tasks are (1) toxicity monitoring; (2) bioaccumulation monitoring of nonradiological contaminants in aquatic biota; (3) biological indicator studies; (4) instream ecological monitoring; (5) assessment of contaminants in the terrestrial environment; (6) radioecology of WOC and White Oak Lake (WOL); and (7) contaminant transport, distribution, and fate in the WOC embayment-Clinch River-Watts Bar Reservoir system. This document, the first of a series of annual reports presenting the results of BMAP, describes studies that were conducted from March through December 1986.

  7. Biological Monitoring and Abatement Program for the Oak Ridge K-25 Site

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L.A.; Adams, S.M.; Ashwood, T.L.; Blaylock, B.G.; Greeley, M.S.; Loar, J.M.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R. (Oak Ridge National Lab., TN (United States)); Hinzman, R.L. (Oak Ridge Research Inst., TN (United States)); Shoemaker, B.A. (Oak Ridge K-25 Site, TN (United States))

    1993-04-01

    A proposed Biological Monitoring and Abatement Program (BMAP) for the Oak Ridge K-25 Site was prepared in December 1992 as required by the renewed National Pollutant Discharge Elimination System permit that was issued on October 1, 1992. The proposed BMAP is based on results of biological monitoring conducted from 1986 to 1992 and discussions held on November 12, 1992, between staff of Martin Marietta Energy Systems, Inc. (Oak Ridge National Laboratory and the K-25 Site), and the Tennessee Department of Environment and Conservation, Department of Energy Oversight Division. The proposed BMAP consists of four tasks that reflect different but complementary approaches to evaluating the effects of K-25 Site effluents on the ecological integrity of Mitchell Branch, Poplar Creek, and the Poplar Creek embayment of the Clinch River. These tasks include (1) ambient toxicity monitoring, (2) bioaccumulation monitoring, (3) assessment of fish health, and (4) instream monitoring of biological communities. This overall BMAP plan combines established protocols with current biological monitoring techniques to assess environmental compliance and quantify ecological recovery. The BMAP will also determine whether the effluent limits established for the K-25 Site protect the designated use of the receiving streams (Mitchell Branch, Poplar Creek, and Clinch River) for growth and propagation of fish and other aquatic life. Results obtained from this biological monitoring program will also be used to document the ecological effects (and effectiveness) of remedial actions.

  8. Biological Monitoring and Abatement Program for the Oak Ridge K-25 Site

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L. A.; Adams, S. M.; Ashwood, T. L.; Blaylock, B. G.; Greeley, M. S.; Loar, J. M.; Peterson, M. J.; Ryon, M. G.; Smith, J. G.; Southworth, G. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Div.; Shoemaker, B. A. [Oak Ridge K-25 Site, TN (United States); Hinzman, R. L. [Oak Ridge Research Inst., TN (United States)

    1993-02-01

    A proposed Biological Monitoring and Abatement Program (BMAP) for the Oak Ridge K-25 Site was prepared in December 1992 as required by the renewed National Pollutant Discharge Elimination System permit that was issued on October 1, 1992. The proposed BMAP consists of four tasks that reflect different but complementary approaches to evaluating the effects of K-25 Site effluents on the ecological integrity of Mitchell Branch, Poplar Creek, and the Poplar Creek embayment of the Clinch River. These tasks include (1) ambient toxicity monitoring, (2) bioaccumulation monitoring, (3) assessment of fish health, and (4) instream monitoring of biological communities. This overall BMAP plan combines established protocols with current biological monitoring techniques to assess environmental compliance and quantify ecological recovery. The BMAP will also determine whether the effluent limits established for the K-25 Site protect the designated use of the receiving streams (Mitchell Branch, Poplar Creek, and Clinch River) for growth and propagation of fish and other aquatic life. Results obtained from this biological monitoring program will also be used to document the ecological effects (and effectiveness) of remedial actions.

  9. Mercury issues related to NPDES and the CERCLA watershed project at the Oak Ridge Y-12 Plant

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The purpose of this document is to present the current understanding of the issues and options surrounding compliance with the current National Pollutant Discharge Elimination System (NPDES) permit conditions. This is a complicated issue that directly impacts, and will be directly impacted by, ongoing CERCLA activities in Lower East Fork Poplar Creek and the Clinch River/Poplar Creek. It may be necessary to reconstitute the whole and combine actions and decisions regarding the entire creek (origin to confluence with the Clinch River) to develop a viable long-term strategy that meets regulatory goals and requirements as well as those of DOE`s 10-Year Plan and the new watershed management permitting approach. This document presents background information on the Reduction of Mercury in Plant Effluents (RMPE) and NPDES programs insofar as it is needed to understand the issues and options. A tremendous amount of data has been collected to support the NPDES/RMPE and CERCLA programs. These data are not presented, although they may be referenced and conclusions based on them may be presented, as necessary, to support discussion of the options.

  10. Ecotoxicity of materials from integrated two-stage liquefaction and Exxon Donor Solvent processes

    Energy Technology Data Exchange (ETDEWEB)

    Dauble, D.D.; Scott, A.J.; Lusty, E.W.; Thomas, B.L.; Hanf, R.W. Jr.

    1983-05-01

    Coal-derived materials from two coal conversion processes were screened for potential ecological toxicity. We examined the toxicity of materials from different engineering or process options to an aquatic invertebrate and also related potential hazard to relative concentration, composition, and stability of water soluble components. For materials tested from the Integrated Two-Stage Liquefaction (ITSL) process, only the LC finer (LCF) 650/sup 0/F distillate was highly soluble in water at 20/sup 0/C. The LCF feed and Total Liquid Product (TLP) were not in liquid state at 20/sup 0/C and were relatively insoluble in water. Relative hazard to daphnids from ITSL materials was as follows: LCF 650/sup 0/F distillate greater than or equal to LCF feed greater than or equal to TLP. For Exxon Donor Solvent (EDS) materials, process solvent produced in the bottoms recycle mode was more soluble in water than once-through process solvent and, hence, slightly more acutely toxic to daphnids. When compared to other coal liquids or petroleum products, the ITSL or EDS liquids were intermediate in toxicity; relative hazard ranged from 1/7 to 1/13 of the Solvent Refined Coal (SRC)-II distillable blend, but was several times greater than the relative hazard for No. 2 diesel fuel oil or Prudhoe Bay crude oil. Although compositonal differences in water-soluble fractions (WSF) were noted among materials, phenolics were the major compound class in all WSFs and probably the primary contributor to acute toxicity.

  11. Improving the reliability of aquatic toxicity testing of hydrophobic chemicals via equilibrium passive dosing - A multiple trophic level case study on bromochlorophene.

    Science.gov (United States)

    Stibany, Felix; Ewald, Franziska; Miller, Ina; Hollert, Henner; Schäffer, Andreas

    2017-01-28

    The main objective of the present study was to improve the reliability and practicability of aquatic toxicity testing of hydrophobic chemicals based upon the model substance bromochlorophene (BCP). Therefore, we adapted a passive dosing format to test the toxicity of BCP at different concentrations and in multiple test systems with aquatic organisms of various trophic levels. At the same time, the method allowed for the accurate determination of exposure concentrations (i.e., in the presence of exposed organisms; Ctest) and freely dissolved concentrations (i.e., without organisms present; Cfree) of BCP in all tested media. We report on the joint adaptation of three ecotoxicity tests - algal growth inhibition, Daphnia magna immobilization, and fish-embryo toxicity - to a silicone O-ring based equilibrium passive dosing format. Effect concentrations derived by passive dosing methods were compared with corresponding effect concentrations derived by standard co-solvent setups. The passive dosing format led to EC50-values in the lower μgL(-1) range for algae, daphnids, and fish embryos, whereas increased effect concentrations were measured in the co-solvent setups for algae and daphnids. This effect once more shows that passive dosing might offer advantages over standard methods like co-solvent setups when it comes to a reliable risk assessment of hydrophobic substances. The presented passive dosing setup offers a facilitated, practical, and repeatable way to test hydrophobic chemicals on their toxicity to aquatic organisms, and is an ideal basis for the detailed investigation of this important group of chemicals.

  12. Assessment of the effects of the carbamazepine on the endogenous endocrine system of Daphnia magna.

    Science.gov (United States)

    Oropesa, A L; Floro, A M; Palma, P

    2016-09-01

    In the present study, the endocrine activity of the antiepileptic pharmaceutical carbamazepine (CBZ) in the crustacean Daphnia magna was assessed. To assess the hormonal activity of the drug, we exposed maternal daphnids and embryos to environmental relevant concentrations of CBZ (ranging from 10 to 200 μg/L) and to mixtures of CBZ with fenoxycarb (FEN; 1 μg/L). Chronic exposure to CBZ significantly decreased the reproductive output and the number of molts of D. magna at 200 μg/L. This compound induced the production of male offspring (12 ± 1.7 %), in a non-concentration-dependent manner, acting as a weak juvenile hormone analog. Results showed that this substance, at tested concentrations, did not antagonize the juvenoid action of FEN. Further, CBZ has shown to be toxic to daphnid embryos through maternal exposure interfering with their normal gastrulation and organogenesis stages but not producing direct embryo toxicity. These findings suggest that CBZ could act as an endocrine disruptor in D. magna as it decreases the reproductive output, interferes with sex determination, and causes development abnormality in offspring. Therefore, CBZ could directly affect the population sustainability.

  13. Rational selection of alternative, environmentally compatible surfactants for biotechnological production of pharmaceuticals--a step toward green biotechnology.

    Science.gov (United States)

    Straub, Jürg Oliver; Shearer, Russel; Studer, Martin

    2014-09-01

    The biotechnological production of pharmaceutical active substances needs ancillary substances. Surfactants are used at the end of the cell culture as a protection against potential viral or bacterial contamination and to lyse the producing cells for isolation and purification of the products. To find a replacement for a surfactant that had raised environmental concern, environmentally relevant data for potential alternatives were searched for in the literature. Significant data gaps were filled with additional tests: biodegradability, algal growth inhibition, acute daphnid immobilization and chronic daphnid reproduction toxicity, acute fish toxicity, and activated sludge respiration inhibition. The results were used to model removal in the wastewater treatment plants (WWTPs) serving 3 biotechnological production sites in the Roche Group. Predicted environmental concentrations (PECs) were calculated using realistic amounts of surfactants and site-specific wastewater fluxes, modeled removals for the WWTPs and dilution factors by the respective receiving waters. Predicted no-effect concentrations (PNECs) were derived for WWTPs and for both fresh and marine receiving waters as the treated wastewater of 1 production site is discharged into a coastal water. This resulted in a spreadsheet showing PECs, PNECs, and PEC ÷ PNEC risk characterization ratios for the WWTPs and receiving waters for all investigated surfactants and all 3 sites. This spreadsheet now serves as a selection support for the biotechnological developers. This risk-based prioritization of surfactants is a step toward green biotechnological production.

  14. TiO2 Nanoparticle Uptake by the Water Flea Daphnia magna via Different Routes is Calcium-Dependent.

    Science.gov (United States)

    Tan, Ling-Yan; Huang, Bin; Xu, Shen; Wei, Zhong-Bo; Yang, Liu-Yan; Miao, Ai-Jun

    2016-07-19

    Calcium plays versatile roles in aquatic ecosystems. In this study, we investigated its effects on the uptake of polyacrylate-coated TiO2 nanoparticles (PAA-TiO2-NPs) by the water flea (cladoceran) Daphnia magna. Particle distribution in these daphnids was also visualized using synchrotron radiation-based micro X-ray fluorescence spectroscopy, transmission electron microscopy, and scanning electron microscopy. At low ambient Ca concentrations in the experimental medium ([Ca]dis), PAA-TiO2-NPs were well dispersed and distributed throughout the daphnid; the particle concentration was highest in the abdominal zone and the gut, as a result of endocytosis and passive drinking of the nanoparticles, respectively. Further, Ca induced PAA-TiO2-NP uptake as a result of the increased Ca influx. At a high [Ca]dis, the PAA-TiO2-NPs formed micrometer-sized aggregates that were ingested by D. magna and concentrated only in its gut, independent of the Ca influx. Our results demonstrated the multiple effects of Ca on nanoparticle bioaccumulation. Specifically, well-dispersed nanoparticles were taken up by D. magna through endocytosis and passive drinking whereas the uptake of micrometer-sized aggregates relied on active ingestion.

  15. Development and staging of the water flea Daphnia magna (Straus, 1820; Cladocera, Daphniidae) based on morphological landmarks.

    Science.gov (United States)

    Mittmann, Beate; Ungerer, Petra; Klann, Marleen; Stollewerk, Angelika; Wolff, Carsten

    2014-03-18

    Crustaceans of the genus Daphnia are one of the oldest model organisms in ecotoxicology, ecology and evolutionary biology. The publication of the Daphnia pulex genome has facilitated the development of genetic tools to answer long-standing questions in these research fields (Science 331: 555-561, 2011). A particular focus is laid on understanding the genetic basis of the striking ability of daphnids to change their phenotype in response to environmental stressors. Furthermore, Daphnia have recently been developed into crustacean model organisms for EvoDevo research, contributing to the ongoing attempt to resolve arthropod phylogeny. These problems require the comparative analyses of gene expression and functional data, which in turn require a standardized developmental staging system for Daphnia. Here we provide a detailed staging system of the embryonic development of Daphnia magna based on morphological landmarks. The staging system does not rely on developmental hours and is therefore suitable for functional and ecological experiments, which often cause developmental delays in affected embryos and thus shifts in time reference points. We provide a detailed description of each stage and include schematic drawings of all stages showing relevant morphological landmarks in order to facilitate the application of this staging scheme. We present here a staging system for Daphnia magna, which is based on morphological landmarks. The staging system can be adopted for other daphnids with minor variations since the sequence of development is highly conserved during early stages and only minor heterochronic shifts occur in late embryonic stages.

  16. Read-Across Prediction of the Acute Toxicity of Organic Compounds toward the Water Flea Daphnia magna.

    Science.gov (United States)

    Kühne, Ralph; Ebert, Ralf-Uwe; von der Ohe, Peter C; Ulrich, Nadin; Brack, Werner; Schüürmann, Gerrit

    2013-01-01

    According to the European REACH Directive, the acute daphnid toxicity needs to be assessed for industrial chemicals with market volumes ≥1 t/a. Employing a data set of 1365 organic compounds with experimental 48-h LC50 data for Daphnia magna, a read-across approach has been developed that makes use of the atom-centered fragment (ACF) method as quantitative measure for structural similarity. Both quantitative log LC50 predictions and a discrimination between narcosis-level and excess toxicity can be obtained, augmented by similarity-triggered information that characterizes a compound as inside or outside the quantitative or qualitative model domain. Reading across proceeds as interpolation of the toxicity enhancement (Te ) over predicted narcosis-level toxicity, taking experimental log Te values from similarity-selected reference compounds as input. The resultant decision tree model yields r(2) =0.85 and rms=0.66 for the subset of 757 compounds (56 %) identified as inside the quantitative model domain, and can handle further 318 compounds (23 %) with the categorical submodel, with 290 compounds (21 %) being outside its domain. The new in silico approach appears useful as ITS (Integrated Testing Strategy) tool for the daphnid toxicity assessment. The discussion includes a comparison of Kow - and LSER-predicted narcosis-level toxicity in the read-across context. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Metabolomics reveals an involvement of pantothenate for male production responding to the short-day stimulus in the water flea, Daphnia pulex.

    Science.gov (United States)

    Toyota, Kenji; Gavin, Alex; Miyagawa, Shinichi; Viant, Mark R; Iguchi, Taisen

    2016-04-26

    Under favorable conditions, the micro-crustacean Daphnia pulex produces female offspring by parthenogenesis, whereas under unfavorable conditions, they produce male offspring to induce sexual reproduction (environmental sex determination: ESD). We recently established a suitable system for ESD studies using D. pulex WTN6 strain, in which the sex of the offspring can be regulated by alterations in day-length; long-day and short-day conditions can induce female and male offspring, respectively. Taking advantage of this system, we have already demonstrated that methyl farnesoate (MF) synthesis is necessary for male offspring production, and identified ionotropic glutamate receptors as an upstream regulator of MF signaling. Despite these findings, the molecular mechanisms associated with MF signaling have not yet been well elucidated. In this study, we analyzed the whole metabolic profiles of mother daphnids reared under long-day (female-producing) and short-day (male-producing) conditions, and discovered that pantothenate (vitamin B5), a known precursor to coenzyme A, was significantly accumulated in response to the short-day condition. To confirm the innate role of pantothenate in D. pulex, this metabolite was administered to mother daphnids resulting in a significantly increased proportion of male offspring producing mothers. This study provides novel insights of the metabolic mechanisms of the ESD system in D. pulex.

  18. Protein kinase C is involved with upstream signaling of methyl farnesoate for photoperiod-dependent sex determination in the water flea Daphnia pulex.

    Science.gov (United States)

    Toyota, Kenji; Sato, Tomomi; Tatarazako, Norihisa; Iguchi, Taisen

    2017-02-15

    Sex determination of Daphnia pulex is decided by environmental conditions. We established a suitable experimental system for this study using D. pulex WTN6 strain, in which the sex of the offspring can be controlled by photoperiod. Long-day conditions induced females and short-day conditions induced males. Using this system, we previously found that methy farnesoate (MF), which is a putative innate juvenile hormone molecule in daphnids, is necessary for male sex determination and that protein kinase C (PKC) is a candidate factor of male sex determiner. In this study, we demonstrated that a PKC inhibitor [bisindolylmaleimide IV (BIM)] application strongly suppressed male offspring induction in the short-day condition. Moreover, co-treatment of BIM with MF revealed that PKC signaling acts upstream of MF signaling for male sex determination. This is the first experimental evidence that PKC is involved in the male sex determination process associated with methyl farnesoate signaling in daphnid species. © 2017. Published by The Company of Biologists Ltd.

  19. Influence of environmental factors on the response of a natural population of Daphnia magna (Crustacea: Cladocera) to spinosad and Bacillus thuringiensis israelensis in Mediterranean coastal wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Duchet, C. [Entente Interdepartementale de Demoustication du Littoral Mediterraneen, 165 avenue Paul-Rimbaud, Montpellier F-34184 (France); INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France); Caquet, Th. [INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France); Franquet, E. [Universite Paul Cezanne, Institut Mediterraneen d' Ecologie et de Paleoecologie, Faculte des Sciences et Techniques Saint Jerome, C31, Marseille F-13397 (France); Lagneau, C. [Entente Interdepartementale de Demoustication du Littoral Mediterraneen, 165 avenue Paul-Rimbaud, Montpellier F-34184 (France); Lagadic, L., E-mail: Laurent.Lagadic@rennes.inra.f [INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France)

    2010-05-15

    The present study was undertaken to assess the impact of a candidate mosquito larvicide, spinosad (8, 17 and 33 mug L{sup -1}) on a field population of Daphnia magna under natural variations of water temperature and salinity, using Bti (0.16 and 0.50 muL L{sup -1}) as the reference larvicide. Microcosms (125 L) were placed in a shallow temporary marsh where D. magna was naturally present. The peak of salinity observed during the 21-day observation period may have been partly responsible for the decrease of daphnid population density in all the microcosms. It is also probably responsible for the absence of recovery in the microcosms treated with spinosad which caused a sharp decrease of D. magna abundance within the first two days following treatment whereas Bti had no effect. These results suggest that it may be difficult for a field population of daphnids to cope simultaneously with natural (water salinity and temperature) and anthropogenic (larvicides) stressors. - Significant interaction between salinity and spinosad exposure impairs the recovery of a natural population of Daphnia magna.

  20. Effects of Ammonia and Density on Filtering of Commensal and Pathogenic Escherichia coli by the Cladoceran Daphnia magna.

    Science.gov (United States)

    Nørgaard, Louise Solveig; Roslev, Peter

    2016-12-01

    Grazing by cladocerans can reduce the survival of enteric bacteria associated with fecal pollution. This study examined the potential of Daphnia magna to filter commensal and pathogenic Escherichia coli of human origin. Grazing on commensal and pathogenic bacteria was comparable, but slightly greater at 20 compared to 15 and 25°C. Filtering activity was strongly dependent on D. magna and E. coli densities at environmentally relevant bacterial concentrations. Maximum feeding rates were >10(7) cells h(-1) daphnid(-1), clearance rates were 1-6 mL h(-1) daphnid(-1), and filtering was independent of bacterial cell sizes between 0.7 and 1.8 µm. Filtering and ingestion of E. coli by D. magna was susceptible to acute inhibition by unionized ammonia with a 24 h EC50 of 0.18 mg L(-1) NH3-N, and a LOEC of 0.09 mg L(-1) NH3-N. The study indicated that biological and chemical constraints should be considered when applying Daphnia for attenuation of fecal pollution.

  1. Abandoned coal mining sites: using ecotoxicological tests to support an industrial organic sludge amendment.

    Science.gov (United States)

    Chiochetta, Claudete G; Radetski, Marilice R; Corrêa, Albertina X R; Tischer, Vinícius; Tiepo, Erasmo N; Radetski, Claudemir M

    2013-11-01

    The different stages involved in coal mining-related activities result in a degraded landscape and sites associated with large amounts of dumped waste material. Remediation of these contaminated soils can be carried out by application of industrial organic sludge if the concerns regarding the potential negative environmental impacts of this experimental practice are properly addressed. In this context, the objective of this study was to use ecotoxicological tests to determine the quantity of organic industrial sludge that is required as a soil amendment to restore soil production while avoiding environmental impact. Chemical analysis of the solids (industrial sludge and soil) and their leachates was carried out as well as a battery of ecotoxicity tests on enzymes (hydrolytic activity), bacteria, algae, daphnids, earthworms, and higher plants, according to standardized methodologies. Solid and leachate samples of coal-contaminated soil were more toxic than those of industrial sludge towards enzyme activity, bacteria, algae, daphnids, and earthworms. In the case of the higher plants (lettuce, corn, wild cabbage, and Surinam cherry) the industrial sludge was more toxic than the coal-contaminated soil, and a soil/sludge mixture (66:34% dry weight basis) had a stimulatory effect on the Surinam cherry biomass. The ecotoxicological assessment of the coal-contaminated soil remediation using sludge as an amendment is very important to determine application rates that could promote a stimulatory effect on agronomic species without negatively affecting the environment.

  2. Toxicological benchmarks for screening of potential contaminants of concern for effects on aquatic biota on the Oak Ridge Reservation, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Sutter, G.A. II (Oak Ridge National Lab., TN (United States)); Futrell, M.A. (East Tennessee State Univ., Johnson City, TN (United States)); Kerchner, G.A. (Harvard Coll., Cambridge, MA (United States))

    1992-09-01

    This report presents potential screening benchmarks for protection of aquatic life from contaminants in water. Because there is no guidance for screening benchmarks, a set of alternative benchmarks is presented here. The alternative benchmarks are based on different conceptual approaches to estimating concentrations causing significant effects. For the upper screening benchmark, they are the acute National Ambient Water Quality Criterion (NAWQC) and the acute pesticide advisory value (a concentration that is estimated with 95% confidence not to exceed the unknown acute NAWQC for those chemicals with no NAWQC). The alternative chronic benchmarks are the chronic NAWQC, the chronic pesticide screening value, the lowest chronic values for fish and daphnids, the lowest concentration that produces a response in 20% of fish and daphnids [effective concentration 20 (EC[sub 20])] as established through chronic toxicity tests, the estimated EC[sub 20] for a sensitive species, and the concentration estimated to cause a 20% reduction in the recruit abundance of largemouth bass. It is recommended that ambient chemical concentrations be compared to all of these benchmarks. To the extent that toxicity data are available, this report presents the alternative benchmarks for chemicals that have been detected on the Oak Ridge Reservation. It also presents the data used to calculate the benchmarks, and the sources of the data. It compares the benchmarks and discusses their relative conservatism and utility.

  3. Comparison of laboratory batch and flow-through microcosm bioassays.

    Science.gov (United States)

    Clément, Bernard J P; Delhaye, Hélène L; Triffault-Bouchet, Gaëlle G

    2014-10-01

    Since 1997, we have been developing a protocol for ecotoxicological bioassays in 2-L laboratory microcosms and have applied it to the study of various pollutants and ecotoxicological risk assessment scenarios in the area of urban facilities and transport infrastructures. The effects on five different organisms (micro-algae, duckweeds, daphnids, amphipods, chironomids) are assessed using biological responses such as growth, emergence (chironomids), reproduction (daphnids) and survival, with a duration of exposure of 3 weeks. This bioassay has mainly been used as a batch bioassay, i.e., the water was not renewed during the test. A flow-through microcosm bioassay has been developed recently, with the assumption that conditions for the biota should be improved, variability reduced, and the range of exposure patterns enlarged (e.g., the possibility of maintaining constant exposure in the water column). This paper compares the results obtained in batch and flow-through microcosm bioassays, using cadmium as a model toxicant. As expected, the stabilization of physico-chemical parameters, increased organism fitness and reduced variability were observed in the flow-through microcosm bioassay.

  4. Effects of common-use pesticides on developmental and reproductive processes in Daphnia.

    Science.gov (United States)

    Kashian, Donna R; Dodson, Stanley I

    2002-06-01

    Daphnia magna were evaluated for use as a screen for pesticides that have been demonstrated to have estrogenic (o'p'-DDT, di-n-butyl phthalate, toxaphene), anti-androgenic (p'p-DDE, linuron), thyroid (acetochlor, alachlor, metribuzin), insulin (amitraz) or lutenizing hormone (2,4-D) activity in vertebrates, and to establish daphnid sensitivity to these compounds. Pesticides with unknown effects on vertebrate endocrine systems (chlorosulfuran, cyanazine, diflubenzuron, metolachlor, and diquat) were also evaluated. Compounds were assayed for six days at environmentally relevant concentrations ranging from 0.001 to 100 mirog/L, using female Daphnia and their offspring. Sublethal endpoints included offspring sex (sex determination), clutch size (fecundity), and adult size (growth rate). Toxaphene was the only compound that affected sexual differentiation, increasing male production. Daphnia fecundity declined with exposure to toxaphene, and daphnid growth rates were reduced by acetochlor exposure. Diflubenzuron, o'p'-DDT, and p'p-DDE significantly reduced Daphnia survival. No correlation existed between affected reproductive or developmental processes and specific endocrine systems or subsystems. Results from this study indicate that Daphnia make a good screen for assessing potential environmental impacts but are not a useful indicator of pesticide hormonal activity in vertebrates. This assay consistently detected sublethal but ecologically relevant effects of these pesticides on Daphnia at environmentally relevant concentrations typically below their listed EC50 value.

  5. Evaluating the Effects of the Kingston Fly Ash Release on Fish Reproduction: Spring 2009 - 2010 Studies

    Energy Technology Data Exchange (ETDEWEB)

    Greeley Jr, Mark Stephen [ORNL; Adams, Marshall [ORNL; McCracken, Kitty [ORNL

    2012-05-01

    On December 22, 2008, a dike containing fly ash and bottom ash at the Tennessee Valley Authority's (TVA) Kingston Fossil Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits from the spill extended 4 miles upstream of the facility to Emory River mile 6 and downstream to Tennessee River mile 564 ({approx}8.5 miles downstream of the confluence of the Emory River with the Clinch River, and {approx}4 miles downstream of the confluence of the Clinch River with the Tennessee River). A byproduct of coal combustion, fly ash contains a variety of metals and other elements which, at sufficient concentrations and in specific forms, can be harmful to biological systems. The ecological effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to come from elevated levels of certain metals in the ash, particularly selenium, on fish reproduction and fish early life stages (Lemly 1993; Besser and others 1996). The ovaries of adult female fish in a lake contaminated by coal ash were reported to have an increased frequency of atretic oocytes (dead or damaged immature eggs) and reductions in the overall numbers of developing oocytes (Sorensen 1988) associated with elevated body burdens of selenium. Larval fish exposed to selenium through maternal transfer of contaminants to developing eggs in either contaminated bodies of water (Lemly 1999) or in experimental laboratory exposures (Woock and others 1987, Jezierska and others 2009) have significantly increased incidences of developmental abnormalities. Contact of fertilized eggs and developing embryos to ash in water and sediments may also pose an additional risk to the early life stages of exposed fish populations through direct uptake of metals and other ash constituents (Jezierska and others 2009). The establishment and maintenance of fish populations is intimately associated

  6. Evaluation of water quality parameters for monitoring natural, urban, and agricultural areas in the Brazilian Cerrado Avaliação de parâmetros de qualidade de água para monitoramento de áreas naturais, urbanas e agrícolas no Cerrado brasileiro

    Directory of Open Access Journals (Sweden)

    Daphne Heloisa de Freitas Muniz

    2011-09-01

    Full Text Available INTRODUCTION: Brazil's Federal District (FD has seen steep population growth in recent years, and this has increased demand for high-quality water. AIM: The present work aims to evaluate the quality of surface water from two water bodies in the FD at six sampling points, three of which are in the Sobradinho River (the receiving body of a sewage treatment plant effluent and three in the Jardim River (located in an agricultural region. METHODS: Analyses were carried out every thirty days, for twelve months, covering rainy and dry seasons. Parameters were analyzed such as temperature, pH, dissolved oxygen (DO, conductivity, turbidity, total hardness, main ions, total and fecal coliforms (E. coli in water. Ecotoxicological evaluation was also performed, using the micro-crustacean Ceriodaphnia dubia. RESULTS: Data of physical and chemical determinations showed DO, conductivity, Cl-, NO3-, SO4(2- and Na+ to be important in indicating contamination by urban effluents. On the subject of biological parameters - E. coli and ecotoxicological evaluation - the former was seen to be more effective in the urban area. However, in the countryside, the assay with C. dubia proved to be the most sensitive, although less than ideal, because the organism is very sensitive to low water hardness. CONCLUSIONS: The fecal coliform indicator (E. coli was the most effective one for comparing water quality in the two basins, mainly for the urbanized one, while ecotoxicity assays with C. dubia were harmed by the natural chemical composition of the water.INTRODUÇÃO: O Distrito Federal (DF tem apresentado grande crescimento populacional nos últimos anos, o que vem ocasionando aumento da necessidade por água de qualidade, tanto pelas cidades quanto pela área rural. OBJETIVO: O presente trabalho teve como objetivo avaliar a qualidade da água superficial de dois corpos hídricos no DF em seis pontos de amostragem, três localizados no Ribeirão Sobradinho (corpo receptor de

  7. Identifying the causes of oil sands coke leachate toxicity to aquatic invertebrates.

    Science.gov (United States)

    Puttaswamy, Naveen; Liber, Karsten

    2011-11-01

    A previous study found that coke leachates (CL) collected from oil sands field sites were acutely toxic to Ceriodaphnia dubia; however, the cause of toxicity was not known. Therefore, the purpose of this study was to generate CL in the laboratory to evaluate the toxicity response of C. dubia and perform chronic toxicity identification evaluation (TIE) tests to identify the causes of CL toxicity. Coke was subjected to a 15-d batch leaching process at pH 5.5 and 9.5. Leachates were filtered on day 15 and used for chemical and toxicological characterization. The 7-d median lethal concentration (LC50) was 6.3 and 28.7% (v/v) for pH 5.5 and 9.5 CLs, respectively. Trace element characterization of the CLs showed Ni and V levels to be well above their respective 7-d LC50s for C. dubia. Addition of ethylenediaminetetraacetic acid significantly (p ≤ 0.05) improved survival and reproduction in pH 5.5 CL, but not in pH 9.5 CL. Cationic and anionic resins removed toxicity of pH 5.5 CL only. Conversely, the toxicity of pH 9.5 CL was completely removed with an anion resin alone, suggesting that the pH 9.5 CL contained metals that formed oxyanions. Toxicity reappeared when Ni and V were added back to anion resin-treated CLs. The TIE results combined with the trace element chemistry suggest that both Ni and V are the cause of toxicity in pH 5.5 CL, whereas V appears to be the primary cause of toxicity in pH 9.5 CL. Environmental monitoring and risk assessments should therefore focus on the fate and toxicity of metals, especially Ni and V, in coke-amended oil sands reclamation landscapes.

  8. Ecology of phlebotomine sand flies in the rural community of Mont Rolland (Thies region, Senegal: area of transmission of canine leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Massila W Senghor

    Full Text Available BACKGROUND: Different epidemiological studies previously indicated that canine leishmaniasis is present in the region of Thiès (Senegal. However, the risks to human health, the transmission cycle and particularly the implicated vectors are unknown. METHODOLOGY/PRINCIPAL FINDINGS: To improve our knowledge on the population of phlebotomine sand flies and the potential vectors of canine leishmaniasis, sand flies were collected using sticky traps, light traps and indoor spraying method using pyrethroid insecticides in 16 villages of the rural community of Mont Rolland (Thiès region between March and July 2005. The 3788 phlebotomine sand flies we collected (2044 males, 1744 females were distributed among 9 species of which 2 belonged to the genus Phlebotomus: P. duboscqi (vector of cutaneous leishmaniasis in Senegal and P. rodhaini. The other species belonged to the genus Sergentomyia: S. adleri, S. clydei, S. antennata, S. buxtoni, S. dubia, S. schwetzi and S. magna. The number of individuals and the species composition differed according to the type of trap, suggesting variable, species-related degrees of endophily or exophily. The two species of the genus Phlebotomus were markedly under-represented in comparison to the species of the genus Sergentomyia. This study also shows a heterogeneous spatial distribution within the rural community that could be explained by the different ecosystems and particularly the soil characteristics of this community. Finally, the presence of the S. dubia species appeared to be significantly associated with canine leishmaniasis seroprevalence in dogs. CONCLUSIONS/SIGNIFICANCE: Our data allow us to hypothesize that the species of the genus Sergentomyia and particularly the species S. dubia and S. schwetzi might be capable of transmitting canine leishmaniasis. These results challenge the dogma that leishmaniasis is exclusively transmitted by species of the genus Phlebotomus in the Old World. This hypothesis should be

  9. Dispersion and toxicity of selected manufactured nanomaterials in natural river water samples: effects of water chemical composition.

    Science.gov (United States)

    Gao, Jie; Youn, Sejin; Hovsepyan, Anna; Llaneza, Veronica L; Wang, Yu; Bitton, Gabriel; Bonzongo, Jean-Claude J

    2009-05-01

    Experimental conditions that mimic likely scenarios of manufactured nanomaterials (MNs) introduction to aquatic systems were used to assessthe effect of nanoparticle dispersion/solubility and water chemical composition on MN-toxicity. Aqueous suspensions of fullerenes (C60), nanosilver (nAg), and nanocopper (nCu) were prepared in both deionized water and filtered (0.45 microm) natural river water samples collected from the Suwannee River basin, to emphasize differences in dissolved organic carbon (DOC) concentrations and solution ionic strengths (I). Two toxicity tests, the Ceriodaphnia dubia and MetPLATE bioassays were used. Results obtained from exposure studies show that water chemistry affects the suspension/solubility of MNs as well as the particle size distribution, resulting in a wide range of biological responses depending on the type of toxicity test used. Under experimental conditions used in this study, C60 exhibited no toxicity even when suspended concentrations exceeded 3 mg L(-1). MetPLATE results showed that the toxicity of aqueous suspensions of nCu tends to increase with increasing DOC concentrations, while increasing I reduces nCu toxicity. The use of the aquatic invertebrate C. dubia on the other hand showed a tendency for decreased mortality with increasing DOC and I. MetPLATE results for nAg showed decreasing trends in toxicity with increasing DOC concentrations and I. However, C. dubia exhibited contrasting biological responses, in that increasing DOC concentrations reduced toxicity, while the latter increased with increasing I. Overall, our results show that laboratory experiments that use DI-water and drastic MN-suspension methods may not be realistic as MN-dispersion and suspension in natural waters vary significantly with water chemistry and the reactivity of MNs.

  10. The effect of food on the acute toxicity of silver nitrate to four freshwater test species and acute-to-chronic ratios.

    Science.gov (United States)

    Naddy, Rami B; McNerney, Gina R; Gorsuch, Joseph W; Bell, Russell A; Kramer, James R; Wu, Kuen B; Paquin, Paul R

    2011-11-01

    Acute silver toxicity studies were conducted with and without food for four common freshwater test species: Daphnia magna, Ceriodaphnia dubia, Pimephales promelas (fathead minnow-FHM), and Oncorhynchus mykiss (rainbow trout-RBT) in order to generate acute-to-chronic ratios (ACR). The studies were conducted similarly (i.e., static-renewal or flow-through) to chronic/early-life stage studies that were previously performed in this laboratory. The acute toxicity (EC/LC50 values) of silver without food ranged from 0.57 μg dissolved Ag/l for C.dubia to 9.15 μg dissolved Ag/l for RBT. The presence of food resulted in an increase in EC/LC50 values from 1.25× for RBT to 22.4× for C. dubia. Invertebrate food type was also shown to effect acute silver toxicity. Food did not affect EC/LC50s or ACRs as greatly in fish studies as in invertebrate studies. ACRs for both invertebrate species were <1.0 when using acute studies without food but were 1.22 and 1.33 when using acute studies with food. ACRs for FHMs ranged from 4.06 to 7.19, while RBT ACRs ranged from 28.6 to 35.8 depending on whether food was present in acute studies. The data generated from this research program should be useful in re-determining a final ACR for silver in freshwater as well as in risk assessments.

  11. Competencia en Cladocera: implicancias de la sobreposición en el uso de los recursos tróficos Competition in Cladocera: implications of the trophic resources use overlap

    Directory of Open Access Journals (Sweden)

    GINGER MARTINEZ

    2000-12-01

    Full Text Available A pesar que numerosa evidencia demuestra el uso de diferentes estrategias de alimentación entre cladóceros, la clásica descripción de una conducta alimentaria pasiva ha conducido a una subestimación de la sobreposición de nicho trófico sobre sus patrones de coexistencia. En condiciones de microcosmos, se mantuvieron experimentos pareados de dinámica poblacional de los cladóceros Moina micrura (Moinidae y Ceriodaphnia dubia (Daphnidae, especializados en los recursos Chlorella sp. y Oocystis sp. (Chlorococcales respectivamente y del generalista Daphnia ambigua (Daphnidae, durante 35 - 45 días. Mientras que los especialistas M. micrura y C. dubia no dieron evidencias de competencia, la presencia de cada uno produjo un significativo decrecimiento de la densidad del generalista D. ambigua, ocasionando en algunos casos su extinción. A pesar que las dinámicas poblacionales de cada especialista fueron afectadas cualitativamente por la presencia del generalista, no hubo efecto de esta especie sobre las densidades, resultando una interacción asimétrica entre cada especialista con el generalista. Estos resultados demuestran que la conducta alimentaria y la sobreposición en el uso de los recursos serían condiciones determinantes en la composición de ensambles de cladócerosAlthough numerous evidence reveals the use of different feeding strategies among cladocerans, the impact of trophic niche overlap on their patterns of coexistence has been underestimated due to the classical description of passive feeding behavior. Under microcosm conditions, paired experiments of population dynamics were conducted for the cladocerans Moina micrura (Moinidae and Ceriodaphnia dubia (Daphnidae, specialists on the resources Chlorella sp. and Oocystis sp. (Chlorococcales respectively, and for the generalist species Daphnia ambigua (Daphnidae, during 35 - 45 days. While, the specialists M. micrura and C. dubia did not show evidences of competition, their

  12. Report of Prionospio complex (Annelida: Polychaeta: Spionidae) from China' s waters, with description of a new species

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jin; LI Xinzheng

    2009-01-01

    Nine species of Prionospio complex are recorded from China' s waters, including one new species and six newly recorded species. Prionospio (Priorvaspio) pacifica sp. Nov. , is characterized by having first and forth pairs of branchiae pinnate, second and third pairs of apinnate, ventral crest on Setiger 9 and dorsal crests on Setigers 10-25. Apoprionospio kirrae (Wilson, 1990), Prionospio (Aquilaspio) convexa Imajima, 1990, Prionospio (Minuspio) muhibranchiata Berkeley, 1927, Prionospio (Prionospio) bocki Soderstrom, 1920, Prionospio (Prionospio) dubia Maciolek, 1985 and Prionospio (Prionospio) paradisea Imajima, 1990 are recorded for the first time from China' s waters.

  13. Morphological and Molecular Identification of Three Ceriodaphnia Species (Cladocera: Daphniidae from Australia

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    Pranay Sharma

    2014-01-01

    Full Text Available Australian Ceriodaphnia (Cladocera: Daphniidae are examined using morphological attributes and two mitochondrial DNA (COI and 16s and one nuclear DNA (28s gene fragments to differentiate the species. The sequence data supports the existence of three species, that is, C. dubia, one reinstated species C. spinata Henry, 1919, and one new species C. sp. 1. Morphological characteristics were also able to accurately separate the three species. Furthermore, genetic analysis of COI sequences from Ceriodaphnia supported three clades. The high degree of correlation between morphological and molecular identification in this study indicates that mitochondrial markers, COI and 16s, are appropriate molecular markers for species discrimination and identification of Ceriodaphnia.

  14. PROPAGAÇÃO ASSEXUADA DO CAMU-CAMU (Myrciaria dúbia) ATRAVÉS DE ENXERTIAS DO TIPO GARFAGEM

    OpenAIRE

    FERREIRA,Sidney Alberto do N; GENTIL,Daniel Felipe de O.

    1997-01-01

    O camu-camu (Myrciaria dubia (H.B.K.) McVaugh), espécie nativa da Amazônia, cujos frutos apresentam elevado teor de vitamina C, normalmente é propagado através da semente o que não garante a reprodução de bons caracteres. Esta pesquisa teve por objetivo avaliar a multiplicação do camu-camu por meio de diferentes métodos de enxertias do tipo garfagem, visando a produção de material selecionado na região de Manaus, AM. As enxertia...

  15. Estrategias bioinformáticas y moleculares para aislar genes con potencial biotecnológico a partir de especies huérfanas de la ciencia

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    Juan Castro Gómez

    2013-12-01

    Full Text Available La amazonía peruana es megabiodiversa y posee millones de genes con potencial biotecnológico que debemos descubrir. Para identificarlos, aislarlos y poder aprovecharlos tenemos que secuenciar los genomas y transcriptomas de las especies más importantes. Sin embargo, hasta concretar este tipo de proyectos, combinando estrategias bioinformáticas y moleculares podemos aislar genes con potencial biotecnológico. El objetivo fue aislar genes involucrados en la biosíntesis de vitamina C en Myrciaria dubia. De acuerdo a las relaciones filogenéticas de M. dubia con otras especies, se buscaron secuencias homólogas en el banco de genes del gen que codifica L-galactono-1,4-lactona deshidrogenasa (L-GalLDH. En base al alineamiento múltiple obtenido, se construyó un filograma consenso y de los clados formados se diseñaron cebadores degenerados. Los frutos fueron obtenidos de una colección de germoplasma y el ARN total se purificó, el ADNc se sintetizó y amplificó con cebadores degenerados. El amplicón sintetizado se clonó y secuenció con técnicas estándares. Con las aproximaciones empleadas se logró aislar, clonar y secuenciar un segmento de 921 pb del gen L-GalLDH de M. dubia. En conclusión, con las estrategias bioinformáticas y moleculares descritas se aisló el segmento de un gen que codifica la enzima L-galactono-1,4-lactona deshidrogenasa de la vía biosintética de vitamina C en M. dubia, especie de la que no se disponía de secuencias génicas. Con estas mismas aproximaciones será posible aislar genes de interés biotecnológico de esta y otras especies amazónicas que aún no cuentan con bases de datos de secuencias nucleotídicas.

  16. Vliv potravy na úspěšnost vývoje vybraných druhů švábů.

    OpenAIRE

    ŠIŠKOVÁ, Žaneta

    2012-01-01

    The aim of this thesis was to find out whether selected types of food substrates affect the adult´s productivity, the weight of newborn nymphs and laid oothecas and whether changes in adult´s productivity and the weight of nymphs occur due to one source of food during the experiment. In this experiment, the Blaptica dubia, Nauphoeta cinerea and Schelfordella tartara species were used. The reason for selection of those species was their high rate of reproduction, undemanding breeding and a sho...

  17. The myriapodological legacy of Victor Ivanovich Motschoulsky (1810–1871

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    Sergei Golovatch

    2014-07-01

    Full Text Available The little that remains of Motschoulsky’s myriapodological legacy in the collection of Moscow’s Zoological Museum proves to be of very limited value. Only one species of Diplopoda described by Motschoulsky, the Caucasian Hirudisoma roseum (Victor, 1839, is still in use, yet requiring a neotype designation, whereas the remaining few myriapod names he proposed are either nomina dubia or nomina nuda. The former include Scolopendra pentagramma Motschoulsky, 1866 (Chilopoda, Scolopendromorpha, Scolopendridae and Strongylosoma carinulatum Motschoulsky, 1866 (Diplopoda, Polydesmida, Paradoxosomatidae, both from Japan, as well as Julus costulatus Motschoulsky, 1851 (Diplopoda, Callipodida, Schizopetalidae?, from Montenegro, because their type material is either inadequate or missing.

  18. Taxonomic notes on the crab spider genus Tobias Simon, 1895 (Araneae, Thomisidae, Stephanopinae).

    Science.gov (United States)

    Machado, Miguel; Teixeira, Renato Augusto; Lise, Arno Antonio

    2015-10-30

    The males of Tobias caudatus Mello-Leitão, 1929 and Tobias pustulosus Simon, 1929 are described for the first time, females are redescribed and both sexes are illustrated. New distribution records are presented for both species. Tobias monstruosus Mello-Leitão, 1929 is considered a junior synonym of T. pustulosus. The types of Tobias albovittatus Caporiacco, 1954, and Tobias gradiens Mello-Leitão, 1929 are lost, and Tobias albicans Mello-Leitão, 1929 and Tobias corticatus Mello-Leitão, 1917 are known only from poorly preserved specimens, thus they all are considered nomina dubia.

  19. Biting midges of the subfamily Forcipomyiinae (Diptera: Ceratopogonidae) from the Middle East, with keys and descriptions of new species.

    Science.gov (United States)

    Alwin-Kownacka, Alicja; Szadziewski, Ryszard; Szwedo, Jacek

    2016-10-05

    Middle East biting midges of the genera Atrichopogon Kieffer and Forcipomyia Meigen, subfamily Forcipomyiinae Lenz, covering 41 species are reviewed. Two new species are described and illustrated: Forcipomyia (F.) siverekensis Alwin & Szadziewski sp. nov. and Forcipomyia (Microhelea) borkenti Alwin & Szadziewski sp. nov. The list includes 16 species of Atrichopogon and 25 of Forcipomyia. Nine species previously described by Vimmer and Kieffer from the Middle East are treated as nomina dubia and not included in the list.        Keys to identification of Atrichopogon and Forcipomyia species of the Middle East are also provided.

  20. The myriapodological legacy of Victor Ivanovich Motschoulsky (1810-1871).

    Science.gov (United States)

    Golovatch, Sergei

    2014-01-01

    The little that remains of Motschoulsky's myriapodological legacy in the collection of Moscow's Zoological Museum proves to be of very limited value. Only one species of Diplopoda described by Motschoulsky, the Caucasian Hirudisoma roseum (Victor, 1839), is still in use, yet requiring a neotype designation, whereas the remaining few myriapod names he proposed are either nomina dubia or nomina nuda. The former include Scolopendra pentagramma Motschoulsky, 1866 (Chilopoda, Scolopendromorpha, Scolopendridae) and Strongylosoma carinulatum Motschoulsky, 1866 (Diplopoda, Polydesmida, Paradoxosomatidae), both from Japan, as well as Julus costulatus Motschoulsky, 1851 (Diplopoda, Callipodida, Schizopetalidae?), from Montenegro, because their type material is either inadequate or missing.

  1. DNA barcoding and male genital morphology reveal five new cryptic species in the West Palearctic bee Seladonia smaragdula (Vachal, 1895) (Hymenoptera: Apoidea: Halictidae).

    Science.gov (United States)

    Pauly, Alain; Devalez, Jelle; Sonet, Gontran; Nagy, Zoltán Tamás; Boevé, Jean-Luc

    2015-10-29

    Several forms or variants have long been recognized in the West Palearctic sweat bee Seladonia smaragdula (Vachal, 1895). Using DNA barcoding and morphological characters, primarily of the male genitalia, these variants are here recognized and described as five new species: S. gemmella Pauly sp. nov., S. submediterranea Pauly sp. nov., S. orientana Pauly & Devalez sp. nov., S. phryganica Pauly & Devalez sp. nov., and S. cretella Pauly & Devalez sp. nov. Also, we designate a lectotype for Halictus smaragdulus Vachal, consider Seladonia butea (Warncke, 1975) and S. morinella (Warncke, 1975) as nomina dubia, and discuss the identity of the Seladonia specimens from Australia currently determined as S. smaragdula.

  2. Anthoathecatae and Leptothecatae hydroids from Costa Rica (Cnidaria: Hydrozoa).

    Science.gov (United States)

    Kelmo, Francisco; Vargas, Rita

    2002-06-01

    This paper is the first taxonomic account of the hydroid orders Anthoathecatae and Leptothecatae from the Caribbean and Pacific coast of Costa Rica. All specimens are currently stored at the reference collection of the Museo de Zoología, Escuela de Biología, Universidad de Costa Rica. Sixteen hydroid species are recorded: Eudendrium carneum, Pennaria disticha, Acryptolaria longitheca, Plumularia floridana, Halopteris polymorpha, Aglaophenia dubia, Aglaophenia latecarinata, Lytocarpia tridentata, Macrorhynchia phillipina, Macrorhynchia sp., Clytia gracilis, Cnidoscyphus marginatus, Thyroscyphus ramosus, Dynamena disticha, Sertularella diaphana, and Tridentata distans. An extensive synonymy has been given for each species. A simplified taxonomic key is included, and illustrations and descriptions are provided for each species.

  3. Toxicity of arsenic species to three freshwater organisms and biotransformation of inorganic arsenic by freshwater phytoplankton (Chlorella sp. CE-35).

    Science.gov (United States)

    Rahman, M Azizur; Hogan, Ben; Duncan, Elliott; Doyle, Christopher; Krassoi, Rick; Rahman, Mohammad Mahmudur; Naidu, Ravi; Lim, Richard P; Maher, William; Hassler, Christel

    2014-08-01

    In the environment, arsenic (As) exists in a number of chemical species, and arsenite (As(III)) and arsenate (As(V)) dominate in freshwater systems. Toxicity of As species to aquatic organisms is complicated by their interaction with chemicals in water such as phosphate that can influence the bioavailability and uptake of As(V). In the present study, the toxicities of As(III), As(V) and dimethylarsinic acid (DMA) to three freshwater organisms representing three phylogenetic groups: a phytoplankton (Chlorella sp. strain CE-35), a floating macrophyte (Lemna disperma) and a cladoceran grazer (Ceriodaphnia cf. dubia), were determined using acute and growth inhibition bioassays (EC₅₀) at a range of total phosphate (TP) concentrations in OECD medium. The EC₅₀ values of As(III), As(V) and DMA were 27 ± 10, 1.15 ± 0.04 and 19 ± 3 mg L(-1) for Chlorella sp. CE-35; 0.57 ± 0.16, 2.3 ± 0.2 and 56 ± 15 mg L(-1) for L. disperma, and 1.58 ± 0.05, 1.72 ± 0.01 and 5.9 ± 0.1 mg L(-1) for C. cf. dubia, respectively. The results showed that As(III) was more toxic than As(V) to L. disperma; however, As(V) was more toxic than As(III) to Chlorella sp. CE-35. The toxicities of As(III) and As(V) to C. cf. dubia were statistically similar (p>0.05). DMA was less toxic than iAs species to L. disperma and C. cf. dubia, but more toxic than As(III) to Chlorella sp. CE-35. The toxicity of As(V) to Chlorella sp. CE-35 and L. disperma decreased with increasing TP concentrations in the growth medium. Phosphate concentrations did not influence the toxicity of As(III) to either organism. Chlorella sp. CE-35 showed the ability to reduce As(V) to As(III), indicating a substantial influence of phytoplankton on As biogeochemistry in freshwater aquatic systems.

  4. Effects of chronic uranium exposure on life history and physiology of Daphnia magna over three successive generations

    Energy Technology Data Exchange (ETDEWEB)

    Massarin, Sandrine [Laboratoire de Modelisation Environnementale, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Alonzo, Frederic, E-mail: frederic.alonzo@irsn.fr [Laboratoire de Modelisation Environnementale, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Garcia-Sanchez, Laurent [Laboratoire de Modelisation Environnementale, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Gilbin, Rodolphe [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 186, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Garnier-Laplace, Jacqueline [Service d' Etude du Comportement des Radionucleides dans les Ecosystemes, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Poggiale, Jean-Christophe [Laboratoire de Microbiologie, Geochimie et Ecologie Marines (UMR CNRS 6117), Centre d' Oceanologie de Marseille, Universite de la Mediterranee, Campus de Luminy, Case 901, Marseille Cedex 9, 13288 (France)

    2010-09-01

    Daphnia magna was exposed to waterborne uranium (U) at concentrations ranging from 10 to 75 {mu}g L{sup -1} over three successive generations (F0, F1 and F2). Progeny was either exposed to the same concentration as mothers to test whether susceptibility to this radioelement might vary across generations or returned to a clean medium to examine their capacity to recover after parental exposure. Maximum body burdens of 17, 32 and 54 ng U daphnid{sup -1} were measured in the different exposure conditions and converted to corresponding internal alpha dose rates. Low values of 5, 12 and 20 {mu}Gy h{sup -1} suggested that radiotoxicity was negligible compared to chemotoxicity. An increasing sensitivity to toxicity was shown across exposed generations with significant effects observed on life history traits and physiology as low as 10 {mu}g L{sup -1} and a capacity to recover partially in a clean medium after parental exposure to {<=}25 {mu}g L{sup -1}. Using a {sup 14}C-labelled food technique, the study showed that uranium affected carbon assimilation in F0 at concentrations of 25 and 75 {mu}g L{sup -1} (34 and 80% reduction respectively) and as low as 10 {mu}g L{sup -1} in F1 and F2 (40 and 36% reduction respectively). Consequences were strong for both somatic growth and reproduction and increased in severity across generations. Maximum size was reduced by 12% at 75 {mu}g L{sup -1} in F0 and 23% at 25 {mu}g L{sup -1} in F2. Reduction in 21-day fecundity ranged from 27 to 48% respectively at 25 and 75 {mu}g L{sup -1} in F0 and from 43 to 71% respectively at 10 and 25 {mu}g L{sup -1} in F2. Growth retardation caused a delay in deposition of first brood of 1.3 days at 75 {mu}g L{sup -1} in F0, of 1.9 days at 25 {mu}g L{sup -1} in F1 and of 5 days at 25 {mu}g L{sup -1} in F2. Differences in respiration rates and egg dry mass between the control and exposed daphnids were mainly an indirect result of uranium effect on body size. The observed increase in toxic effects across

  5. Bioassay battery interlaboratory investigation of emerging contaminants in spiked water extracts - Towards the implementation of bioanalytical monitoring tools in water quality assessment and monitoring.

    Science.gov (United States)

    Di Paolo, Carolina; Ottermanns, Richard; Keiter, Steffen; Ait-Aissa, Selim; Bluhm, Kerstin; Brack, Werner; Breitholtz, Magnus; Buchinger, Sebastian; Carere, Mario; Chalon, Carole; Cousin, Xavier; Dulio, Valeria; Escher, Beate I; Hamers, Timo; Hilscherová, Klára; Jarque, Sergio; Jonas, Adam; Maillot-Marechal, Emmanuelle; Marneffe, Yves; Nguyen, Mai Thao; Pandard, Pascal; Schifferli, Andrea; Schulze, Tobias; Seidensticker, Sven; Seiler, Thomas-Benjamin; Tang, Janet; van der Oost, Ron; Vermeirssen, Etienne; Zounková, Radka; Zwart, Nick; Hollert, Henner

    2016-11-01

    Bioassays are particularly useful tools to link the chemical and ecological assessments in water quality monitoring. Different methods cover a broad range of toxicity mechanisms in diverse organisms, and account for risks posed by non-target compounds and mixtures. Many tests are already applied in chemical and waste assessments, and stakeholders from the science-police interface have recommended their integration in regulatory water quality monitoring. Still, there is a need to address bioassay suitability to evaluate water samples containing emerging pollutants, which are a current priority in water quality monitoring. The presented interlaboratory study (ILS) verified whether a battery of miniaturized bioassays, conducted in 11 different laboratories following their own protocols, would produce comparable results when applied to evaluate blinded samples consisting of a pristine water extract spiked with four emerging pollutants as single chemicals or mixtures, i.e. triclosan, acridine, 17α-ethinylestradiol (EE2) and 3-nitrobenzanthrone (3-NBA). Assays evaluated effects on aquatic organisms from three different trophic levels (algae, daphnids, zebrafish embryos) and mechanism-specific effects using in vitro estrogenicity (ER-Luc, YES) and mutagenicity (Ames fluctuation) assays. The test battery presented complementary sensitivity and specificity to evaluate the different blinded water extract spikes. Aquatic organisms differed in terms of sensitivity to triclosan (algae > daphnids > fish) and acridine (fish > daphnids > algae) spikes, confirming the complementary role of the three taxa for water quality assessment. Estrogenicity and mutagenicity assays identified with high precision the respective mechanism-specific effects of spikes even when non-specific toxicity occurred in mixture. For estrogenicity, although differences were observed between assays and models, EE2 spike relative induction EC50 values were comparable to the literature, and E2/EE2

  6. Prediction and assessment of ecogenotoxicity of antineoplastic drugs in binary mixtures.

    Science.gov (United States)

    Kundi, Michael; Parrella, Alfredo; Lavorgna, Margherita; Criscuolo, Emma; Russo, Chiara; Isidori, Marina

    2016-08-01

    The combined genotoxic effects of four anticancer drugs (5-fluorouracil [5-FU], cisplatin [CDDP], etoposide [ET], and imatinib mesylate [IM]) were studied testing their binary mixtures in two crustaceans that are part of the freshwater food chain, namely Daphnia magna and Ceriodaphnia dubia. Genotoxicity was assessed using the in vivo comet assay. Assessment was based on two distinct effect sizes determined from dose-response experiments. Doses for single and combined exposures expected to result in these effect sizes were computed based on Bliss independence as reference model. Statistical comparison by analysis of variance of single and combined toxicities allowed accepting or rejecting the independency hypothesis. The results obtained for D. magna showed independent action for all mixtures except for IM+5-FU that showed an antagonistic interaction. In C. dubia, most mixtures had antagonist interactions except IM+5-FU and IM+CDDP that showed Bliss independence. Despite the antagonistic interactions, our results demonstrated that combinations of anticancer drugs could be of environmental concern because effects occur at very low concentrations that are in the range of concentrations encountered in aquatic systems.

  7. Assessing sediment contamination using six toxicity assays

    Directory of Open Access Journals (Sweden)

    Allen G. BURTON Jr.

    2001-08-01

    Full Text Available An evaluation of sediment toxicity at Lake Orta, Italy was conducted to compare a toxicity test battery of 6 assays and to evaluate the extent of sediment contamination at various sediment depths. Lake Orta received excessive loadings of copper and ammonia during the 1900’s until a large remediation effort was conducted in 1989-90 using lime addition. Since that time, the lake has shown signs of a steady recovery of biological communities. The study results showed acute toxicity still exists in sediments at a depth of 5 cm and greater. Assays that detected the highest levels of toxicity were two whole sediment exposures (7 d using Hyalella azteca and Ceriodaphnia dubia. The MicrotoxR assay using pore water was the third most sensitive assay. The Thamnotox, Rototox, Microtox solid phase, and Seed Germination-Root Elongation (pore and solid phase assays showed occasional to no toxicity. Based on similarity of responses and assay sensitivity, the two most useful assays were the C. dubia (or H. azteca and Microtox pore water. These assays were effective at describing sediment toxicity in a weight-of-evidence approach.

  8. Assessment of the ecotoxicological risk of combined sewer overflows for an aquatic system using a coupled "substance and bioassay" approach.

    Science.gov (United States)

    Gooré Bi, Eustache; Monette, Frederic; Gasperi, Johnny; Perrodin, Yves

    2015-03-01

    Very few tools are available for assessing the impact of combined sewer overflows (CSOs) on receiving aquatic environments. The main goal of the study was to assess the ecotoxicological risk of CSOs for a surface aquatic ecosystem using a coupled "substance and bioassay" approach. Wastewater samples from the city of Longueuil, Canada CSO were collected for various rainfall events during one summer season and analyzed for a large panel of substances (n = 116). Four bioassays were also conducted on representative organisms of surface aquatic systems (Pimephales promelas, Ceriodaphnia dubia, Daphnia magna, and Oncorhynchus mykiss). The analytical data did not reveal any ecotoxicological risk for St. Lawrence River organisms, mainly due to strong effluent dilution. However, the substance approach showed that, because of their contribution to the ecotoxicological hazard posed by the effluent, total phosphorus (Ptot), aluminum (Al), total residual chlorine, chromium (Cr), copper (Cu), pyrene, ammonia (N-NH4 (+)), lead (Pb), and zinc (Zn) require more targeted monitoring. While chronic ecotoxicity tests revealed a potential impact of CSO discharges on P. promelas and C. dubia, acute toxicity tests did not show any effect on D. magna or O. mykiss, thus underscoring the importance of chronic toxicity tests as part of efforts aimed at characterizing effluent toxicity. Ultimately, the study leads to the conclusion that the coupled "substance and bioassay" approach is a reliable and robust method for assessing the ecotoxicological risk associated with complex discharges such as CSOs.

  9. 拟细羽束梗孢(新组合)--拟细虫草的无性型%PARAISARIA GRACILIOIDES COMB.NOV., THE ANAMORPH OF CORDYCEPS GRACILIOIDES

    Institute of Scientific and Technical Information of China (English)

    李春如; 明亮; 樊美珍; 李增智

    2004-01-01

    Isaria gracilioides, the anamorph of Cordyceps gracilioides Kobayasi (see also Shimizu, 1994), was described by Kobayasi (1941) on larvae of Cossidae (Coleoptera). The fungus differs from Isaria dubia Delacr., the anamorph of Cordyceps gracilis Durieu & Montagne. The former has much bigger conidia than the latter. Samson & Brady (1983) established a new genus Paraisaria on the base of Isaria dubia which possessed white and loose synnemata consisting of verticillately branched conidiophores with flask-shaped sympodially proliferating phialides. Cordyceps gracilioides and Cordyceps gracilis isolates were successfully collected from China through the method of collecting discharged ascospores from a sterile glass slide and transferring the spores to potato dextrose agar plus 1% peptone (PPDA)(Fan et al., 2001; Li et al., 2002). Recently, Isaria gracilioides was distinguished in the isolate RCEF0921 obtained from the specimen ST000903-01 collected by Y. Y. Chen. The fungus seemed to fit the descriptions of Paraisaria and therefore the following change of the name was made. This is a new record in China.

  10. IDENTIFICATION OF WOOD AND BARK EXTRACTIVES AND THEIR TOXICOLOGICAL EFFECTS ON THE TMP EFFLUENTS

    Institute of Scientific and Technical Information of China (English)

    XiaokunZhang; MohiniSain

    2004-01-01

    Wood extractives in model TMP effluents and bio-treated TMP mill effluent were extracted, isolated with liquid-liquid extraction, and analyzed with GC/MS following sylilation. Acute and chronic toxicity of the effluent samples were tested with Ceriodaphnia dubia. Wood and bark extractives are responsible for the toxicity of the TMP effluent to aquatic life. Resin and fatty acids have a dominating contribution to acute toxicity. Removal of them from the effluent cannot deplete all toxicants, some neutral extractives such as phytosterols, are still chronically toxic to Ceriodaphnia dubia. Wood bark has a dramatic impact on acute toxicity of the TMP effluent. Only 5% of spruce bark addition can increase acute toxicity by 38.4%. However, it has a reverse trend for chronic toxicity, which indicates that some neutral wood extractives may play important role in chronic toxicity of the TMP effluent as well. Successful control of the debarking process and debark effluents is essential for achieving high-quality effluent treatment.

  11. Are there toxic interactions between salinity and naphthenic acids in the toxicity of oil sands process water to freshwater invertebrates?

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, D.; Pasloski, A.; Lanser, B.; Alm, K.; Liber, K. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2009-07-01

    Large volumes of water are used to extract oil from the oil sands in the Athabasca deposit. The resulting oil sands process water (OSPW) has been proposed for use in future reclamation landscapes. Therefore, it is necessary to evaluate the toxicity of OSPW to freshwater invertebrates in order to develop environmentally acceptable OSPW reclamation plans. The OSPW generally contains high concentrations of salts and naphthenic acids (NAs), but low levels of other contaminants such as PAHs and metals. This study investigated the combined toxic effect of NAs and salinity on freshwater invertebrates. Laboratory cultured Ceriodaphnia dubia were used initially to determine the toxicity of OSPW from selected water bodies. The pond waters that generated a toxic response had elevated levels of NAs and salinity, but the concentrations of salinity ions varied considerably among ponds. Results suggested that ion composition may be a factor in toxicity. Subsequent bioassays were performed with single salts and with mixtures representing major ion combinations present in the OSPW, such as carbonate, sulphate, chloride and sodium. The interaction between NAs and salinity was evaluated by exposing Ceriodaphnia dubia and Daphnia pulex to mixtures of NAs extracted from OSPW and relevant major ions chosen according to the salt toxicity test results.

  12. IDENTIFICATION OF WOOD AND BARK EXTRACTIVES AND THEIR TOXICOLOGICAL EFFECTS ON THE TMP EFFLUENTS

    Institute of Scientific and Technical Information of China (English)

    Xiaokun Zhang; Mohini Sain

    2004-01-01

    Wood extractives in model TMP effluents and bio-treated TMP mill effluent were extracted, isolated with liquid-liquid extraction, and analyzed with GC/MS following sylilation. Acute and chronic toxicity of the effluent samples were tested with Ceriodaphnia dubia. Wood and bark extractives are responsible for the toxicity of the TMP effluent to aquatic life. Resin and fatty acids have a dominating contribution to acute toxicity. Removal of them from the effluent cannot deplete all toxicants, some neutral extractives such as phytosterols, are still chronically toxic to Ceriodaphnia dubia. Wood bark has a dramatic impact on acute toxicity of the TMP effluent. Only 5% of spruce bark addition can increase acute toxicity by 38.4%. However, it has a reverse trend for chronic toxicity, which indicates that some neutral wood extractives may play important role in chronic toxicity of the TMP effluent as well. Successful control of the debarking process and debark effluents is essential for achieving high-quality effluent treatment.

  13. Anthoathecatae and Leptothecatae hydroids from Costa Rica (Cnidaria: Hydrozoa

    Directory of Open Access Journals (Sweden)

    Francisco Kelmo

    2002-06-01

    Full Text Available This paper is the first taxonomic account of the hydroid orders Anthoathecatae and Leptothecatae from the Caribbean and Pacific coast of Costa Rica. All specimens are currently stored at the reference collection of the Museo de Zoología, Escuela de Biología, Universidad de Costa Rica. Sixteen hydroid species are recorded: Eudendrium carneum, Pennaria disticha, Acryptolaria longitheca, Plumularia floridana, Halopteris polymorpha, Aglaophenia dubia, Aglaophenia latecarinata, Lytocarpia tridentata, Macrorhynchia phillipina, Macrorhynchia sp., Clytia gracilis, Cnidoscyphus marginatus, Thyroscyphus ramosus, Dynamena disticha, Sertularella diaphana, and Tridentata distans. An extensive synonymy has been given for each species. A simplified taxonomic key is included, and illustrations and descriptions are provided for each speciesEste estudio proporciona el primer informe taxonómico de los hidroides de los Ordenes Anthoathecatae y Leptothecatae presentes en las colecciones del Museo de Zoología de la Escuela de Biología de la Universidad de Costa Rica. Se informan 16 especies de hidroides: Eudendrium carneum, Pennaria disticha, Acryptolaria longitheca, Plumularia floridana, Halopteris polymorpha, Aglaophenia dubia, Aglaophenia latecarinata, Lytocarpia tridentata, Macrorhynchia phillipina, Macrorhynchia sp., Clytia gracilis, Cnidoscyphus marginatus, Thyroscyphus ramosus, Dynamena disticha, Sertularella diaphana y Tridentata distans. Se presenta una exhaustiva revisión de la sinonimia y una clave taxonómica simple e ilustraciones y descripciones para cada una de las especies

  14. Cuticle Fatty Acid Composition and Differential Susceptibility of Three Species of Cockroaches to the Entomopathogenic Fungi Metarhizium anisopliae (Ascomycota, Hypocreales).

    Science.gov (United States)

    Gutierrez, Alejandra C; Gołębiowski, Marek; Pennisi, Mariana; Peterson, Graciela; García, Juan J; Manfrino, Romina G; López Lastra, Claudia C

    2015-04-01

    Differences in free fatty acids (FFAs) chemical composition of insects may be responsible for susceptibility or resistance to fungal infection. Determination of FFAs found in cuticular lipids can effectively contribute to the knowledge concerning insect defense mechanisms. In this study, we have evaluated the susceptibility of three species of cockroaches to the entomopathogenic fungi Metarhizium anisopliae (Metschnikoff) Sorokin by topical application. Mortality due to M. anisopliae was highly significant on adults and nymphs of Blattella germanica L. (Blattodea: Blattellidae). However, mortality was faster in adults than in nymphs. Adults of Blatta orientalis L. (Blattodea: Blattidae) were not susceptible to the fungus, and nymphs of Blaptica dubia Serville (Blattodea: Blaberidae) were more susceptible to the fungus than adults. The composition of cuticular FFAs in the three species of cockroaches was also studied. The analysis indicated that all of the fatty acids were mostly straight-chain, long-chain, saturated or unsaturated. Cuticular lipids of three species of cockroaches contained 19 FFAs, ranging from C14:0 to C24:0. The predominant fatty acids found in the three studied species of cockroaches were oleic, linoleic, palmitic, and stearic acid. Only in adults of Bl. orientalis, myristoleic acid, γ-linolenic acid, arachidic acid, dihomolinoleic acid, and behenic acid were identified. Lignoceric acid was detected only in nymphs of Bl. orientalis. Heneicosylic acid and docosahexaenoic acid were identified in adults of Ba. dubia.

  15. A world checklist of Onychophora (velvet worms), with notes on nomenclature and status of names.

    Science.gov (United States)

    Oliveira, Ivo de Sena; Read, V Morley St J; Mayer, Georg

    2012-01-01

    Currently, the number of valid species of Onychophora is uncertain. To facilitate taxonomic work on this understudied animal group, we present an updated checklist for the two extant onychophoran subgroups, Peripatidae and Peripatopsidae, along with an assessment of the status of each species. According to our study, 82 species of Peripatidae and 115 species of Peripatopsidae have been described thus far. However, among these 197 species, 20 are nomina dubia due to major taxonomic inconsistencies. Apart from nomina dubia, many of the valid species also require revision, in particular representatives of Paraperipatus within the Peripatopsidae, and nearly all species of Peripatidae. In addition to extant representatives, the record of unambiguous fossils includes three species with uncertain relationship to the extant taxa. For all species, we provide a list of synonyms, information on types and type localities, as well as remarks on taxonomic and nomenclatural problems and misspellings. According to recent evidence of high endemism and cryptic speciation among the Peripatidae and Peripatopsidae, previous synonyms are revised. Putative mutations, subspecies and variations are either raised to the species status or synonymised with corresponding taxa. In our revised checklist, we follow the rules and recommendations of the International Code of Zoological Nomenclature to clarify previous inconsistencies.

  16. Revision of early taxa of Australian gall midges (Diptera: Cecidomyiidae).

    Science.gov (United States)

    Kolesik, Peter; Gagné, Raymond J

    2016-12-07

    Australian Cecidomyiidae described by Schiner (1868), Skuse (1888, 1890), Koebele (1893), Felt (1915), Edwards (1916) and Rübsaamen (1916), totalling 111 species and three subgenera, are revised. Chastomera Skuse, 1888 is confirmed to be a junior synonym of Haplusia Karsch, 1878 and Gonioclema Skuse, 1888 and Necrophlebia Skuse, 1888 are declared nomina dubia. Twenty-two species are placed to genus, an additional four species are placed to supertribe or subfamily, all of them redescribed. The remaining species are declared junior synonyms or nomina dubia. Diadiplosis koebelei (Koebele, 1893) is a new junior synonym of Diadiplosis plumbea (Skuse, 1888). Dasineura tomentosa Dorchin, 2011 is a new junior synonym of Dasineura frauenfeldi (Schiner, 1868). Sphenolasioptera Kolesik & Gagné gen. nov. (Cecidomyiinae: Lasiopterini) is erected to contain Sphenolasioptera vastatrix (Skuse, 1888) n. comb. The following genera are recorded from Australia for the first time: Ledomyia Kieffer (Cecidomyiinae: Ledomyiini), represented by L. vitulans (Skuse), n. comb.; Bremia Rondani (Cecidomyiinae: Aphidoletini), represented by B. actiosa (Skuse) n. comb. and B. oreas (Skuse) n. comb.; Divellepidosis Fedotova & Sidorenko (Porricondylinae: Porricondylini), represented by D. pallidina (Skuse) n. comb. and D. indubitata (Skuse) n. comb. Additions are made to the key to genera of Cecidomyiinae of Australia and Papua New Guinea (Kolesik 2014) to accomodate Bremia, Ledomyia and Sphenolasioptera.

  17. A world checklist of Onychophora (velvet worms, with notes on nomenclature and status of names

    Directory of Open Access Journals (Sweden)

    Ivo Oliveira

    2012-07-01

    Full Text Available Currently, the number of valid species of Onychophora is uncertain. To facilitate taxonomic work on this understudied animal group, we present an updated checklist for the two extant onychophoran subgroups, Peripatidae and Peripatopsidae, along with an assessment of the status of each species. According to our study, 82 species of Peripatidae and 115 species of Peripatopsidae have been described thus far. However, among these 197 species, 20 are nomina dubia due to major taxonomic inconsistencies. Apart from nomina dubia, many of the valid species also require revision, in particular representatives of Paraperipatus within the Peripatopsidae, and nearly all species of Peripatidae. In addition to extant representatives, the record of unambiguous fossils includes three species with uncertain relationship to the extant taxa. For all species, we provide a list of synonyms, information on types and type localities, as well as remarks on taxonomic and nomenclatural problems and misspellings. According to recent evidence of high endemism and cryptic speciation among the Peripatidae and Peripatopsidae, previous synonyms are revised. Putative mutations, subspecies and variations are either raised to the species status or synonymised with corresponding taxa. In our revised checklist, we follow the rules and recommendations of the International Code of Zoological Nomenclature to clarify previous inconsistencies.

  18. CROMOSOMAS DE ESPECIES AMERICANAS DE SIDA (MALVACEAE Chromosomes of American species of Sida (Malvaceae

    Directory of Open Access Journals (Sweden)

    Graciela I. Lavia

    2010-08-01

    Full Text Available

    En este trabajo se presentan los números cromosómicos de 26 accesiones del género Sida
    (Malvaceae de Argentina, Bolivia, Brasil, México y Paraguay, pertenecientes a 15 especies.
    Para las siguientes 8 especies se cita el número cromosómico por primera vez: S. Charpinii
    Krapov. 2n=14, S. ciliaris L. 2n=16, S. Monteiroi Krapov. 2n=16, S. anomala A. St.-Hil. 2n=16,
    S. Cristobaliana Krapov. 2n=32, S. dubia A. St.-Hil. & Naudin 2n=14, S. Poeppigiana
    (K.Schum. Fryxell 2n=14 y S. Leitaofilhoi Krapov. 2n=14
    Chromosome numbers are reported for 26 accessions of Sida (Malvaceae from Argentina,
    Bolivia, Brazil, México and Paraguay representing 15 species. First chromosome counts are
    cited for the following 8 species: S. Charpinii Krapov. 2n=14, S. ciliaris L. 2n=16, S. Monteiroi
    Krapov. 2n=16, S. anomala A. St.-Hil. 2n=16, S. Cristobaliana Krapov. 2n=32, S. dubia A. St.-Hil.
    & Naudin 2n=14, S. Poeppigiana (K.Schum. Fryxell 2n=14 and S. Leitaofilhoi Krapov. 2n=14

  19. Pesticide Toxicity Index: a tool for assessing potential toxicity of pesticide mixtures to freshwater aquatic organisms

    Science.gov (United States)

    Nowell, Lisa H.; Norman, Julia E.; Moran, Patrick W.; Martin, Jeffrey D.; Stone, Wesley W.

    2014-01-01

    Pesticide mixtures are common in streams with agricultural or urban influence in the watershed. The Pesticide Toxicity Index (PTI) is a screening tool to assess potential aquatic toxicity of complex pesticide mixtures by combining measures of pesticide exposure and acute toxicity in an additive toxic-unit model. The PTI is determined separately for fish, cladocerans, and benthic invertebrates. This study expands the number of pesticides and degradates included in previous editions of the PTI from 124 to 492 pesticides and degradates, and includes two types of PTI for use in different applications, depending on study objectives. The Median-PTI was calculated from median toxicity values for individual pesticides, so is robust to outliers and is appropriate for comparing relative potential toxicity among samples, sites, or pesticides. The Sensitive-PTI uses the 5th percentile of available toxicity values, so is a more sensitive screening-level indicator of potential toxicity. PTI predictions of toxicity in environmental samples were tested using data aggregated from published field studies that measured pesticide concentrations and toxicity to Ceriodaphnia dubia in ambient stream water. C. dubia survival was reduced to ≤ 50% of controls in 44% of samples with Median-PTI values of 0.1–1, and to 0% in 96% of samples with Median-PTI values > 1. The PTI is a relative, but quantitative, indicator of potential toxicity that can be used to evaluate relationships between pesticide exposure and biological condition.

  20. Painful Lytic Lesions of the Foot : A Case Report

    Directory of Open Access Journals (Sweden)

    R Vaishya

    2015-03-01

    Full Text Available The presence of lytic lesions in the bones of foot raises a number of diagnostic possibilities ranging from infection, inflammatory pathology to neoplastic conditions. Although the radiological picture is not pathognomonic of any pathology, clinical history and histopathological examination can help to clinch the diagnosis. We present a case of multiple lytic lesions of the foot and discuss possible differential diagnoses. The patient was diagnosed as a case of madura foot and the lesions responded to surgical debridement and anti-fungal treatment with a good functional outcome. Madura foot is an uncommon, chronic granulomatous fungal or bacterial infection with a predilection in people who walk barefoot. Although known for a specific geographical distribution, madura foot should be kept as a possible diagnosis in patients presenting with lytic lesions of the foot due to population emigration across the world.

  1. Liquid-metal pumps for large-scale breeder-reactor plant (prototype pump)

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, M. (comp.)

    1976-07-01

    This report presents the recommended pump design for use in Large Scale Liquid Metal Fast Breeder Reactor plants. The base design for the pump will circulate 127,000 GPM of liquid sodium at temperatures up to 850/sup 0/F and with a total discharge head at the design point of 500 feet Na with an impeller that is 40 feet below the sodium seal. The pump design is predicated on developing an impeller design which will have a suction specific speed (S/sub n/) of about 20,000 with 20 feet NPSH available, which will result in a pump speed of 530 RPM at design conditions. The design is based on the technology developed in the design and fabrication of FFTF pumps, the design efforts for the Clinch River Breeder Reactor Pump design study and other technology.

  2. Anti-N-Methyl-D-Aspartate Receptor Encephalitis in HIV Infection

    Directory of Open Access Journals (Sweden)

    Eunice Patarata

    2016-12-01

    Full Text Available Anti-N-methyl-D-aspartate receptor (anti-NMDAR encephalitis is a rare condition characterized by emotional and behavioral disturbances, dyskinesias, and extrapyramidal signs. It occurs in young women of reproductive age and is classically described as a paraneoplastic phenomenon. We present a 36-year-old, HIV-positive female who was admitted to the hospital in an acute confusional state, with a stiff posture, periods of motor agitation, and myoclonic jerks of the hands. Her mental state progressively deteriorated. Without evidence of infection, the presence of anti-NMDAR antibodies both in serum and cerebrospinal fluid clinched the diagnosis of autoimmune encephalitis. No evidence of neoplastic disease was found, and the beneficial response to immunosuppressive therapy was exceptional. This is the first report of anti-NMDAR encephalitis in an HIV-infected individual, reminding us that autoimmune encephalitis should be included in the differential diagnosis of a young patient presenting in an acute confusional state.

  3. Invasive pulmonary mycosis due to Chaetomium globosum with false-positive galactomannan test: a case report and literature review.

    Science.gov (United States)

    Capoor, Malini R; Agarwal, Poojan; Goel, Manoj; Jain, Sarika; Shivaprakash, Mandya Rudramurthy; Honnavar, Prasanna; Gupta, Sunita; Chakrabarti, Arunaloke

    2016-03-01

    In this case, the authors report Chaetomium globosum as a cause of invasive pulmonary infection in a patient with Wegener's granulomatosis. Fungal hyphae (KOH and Calcofluor) were seen on direct microscopy of lung biopsy sample and bronchoalveolar lavage (BAL) sample. C. globosum isolated on culture clinched the diagnosis of invasive pulmonary infection by Chaetomium spp. A positive galactomannan of serum and BAL was repeatedly seen and was utilised for follow-up and as prognostic marker in patient management. The patient was successfully treated with liposomal amphotericin B followed by voriconazole. All the Chaetomium infections reported till date since 1980 are reviewed. Chaetomium spp. with its unique ecology has a hidden clinical potential to cause invasive mould infections.

  4. The Slotnick-Goldfarb′s syndrome in infertility- (a case report

    Directory of Open Access Journals (Sweden)

    Purandare V

    1978-01-01

    Full Text Available A case of the unilateral streaked ovary syndrome is presented with documentation by cytologic, chromosomal, laparoscopic and hormonal studies. This, the Slotnick-Goldfarb′s syndrome, is characterized by oligomenorrhoea progressing into secondary amenorrhoea in a normal phenotypic female with a streaked ovary in one adnexa and an hypoplastic ovary in the other. This case presented with secondary amenorrhoea and primary sterility. She was tall with an increased carrying angle and had hypo plastic breasts and underdeveloped external and internal genitalia. Inves-tigations revealed a normal female karyotype, a mid-zonal matura-tion index, low normal urinary ketosteroids and elevated urinary gonadotrophins. Laparoscopy clinched the diagnosis. The aetiology, prognosis and treatment are briefly discussed. Stress is laid on the fact that whilst investigating a case of sterility and amenorrhoea, this new syndrome must be kept in mind.

  5. Asthma, tuberculosis or eosinophilic pneumonia?

    Directory of Open Access Journals (Sweden)

    Mitra Subhra

    2007-01-01

    Full Text Available A 45 year-old male presented with cough and expectoration for 8 months, short-ness of breath and wheeze for 3 months, and fever for 1 month. He remained symptomatic despite repeated courses of antibiotics with partial relief on oral and inhaled bronchodilators. Despite several sputum examinations being negative for acid fast bacilli (AFB, he was put on anti-tubercular drugs (ATD because of bi-lateral infiltrates on his chest radiographs. A mildly raised blood eosinophil count, eosinophilia in broncho-alveolar lavage (BAL fluid and eosinophilic infiltration on CT guided FNAC from his lung lesion raised the suspicion and the dramatic clinico-radiological improvement with oral corticosteroids clinched the diagnosis of CEP.

  6. 两美企签署小型模块反应堆合同

    Institute of Scientific and Technical Information of China (English)

    王海丹(译); 伍浩松(校)

    2013-01-01

    【英国《国际核工程》网站2013年2月21日报道】美国田纳西流域管理局(TVA)和巴布科克·威尔科克斯公司(Babcock&Wilcox)于2013年2月7日签署一份合同,准备为在田纳西州橡树岭(OakRidge)的克林奇河(ClinchRiver)场址建设一座mPower小型模块反应堆(SMR)启动许可证申请工作。

  7. Probabilistic methods for identification of significant accident sequences in loop-type LMFBRs

    Energy Technology Data Exchange (ETDEWEB)

    Jamali, K M.A.

    1983-06-01

    The aim of the Probabilistic Accident Progression Analysis (PAPA) described herein is to establish a framework for better use of the probability measure; first, as a basis for deterministic calculations, and second, as a part of a comprehensive method for risk assessment in its own right. The achievement of this goal rests on: (1) improvements in the existing approaches for acquisition and analysis of accident sequences; (2) defining a new measure of probabilistic importance that aids in the ranking of sequences of highly uncertain events; and (3) implementation of new techniques for quantification of dependent failures of similar components. The existing techniques related to the above three topics are discussed and the state of the art is reviewed. The PAPA approach is described. The techniques of PAPA are applied to a class of Protected Transients (transients in which the reactor is successfully shutdown) in the Clinch River Breeder Reactor Plant (CRBRP). The results of the application of these techniques are described.

  8. Intra-articular Nodular Fasciitis: An Unexpected Diagnosis for a Joint Lesion: A Case Report

    Directory of Open Access Journals (Sweden)

    MF Michelle Chan

    2014-07-01

    Full Text Available Pathological lesions in and around a joint can arise from underlying dermis, subcutis, deep muscle, bone or synovium. Clinical presentation can include joint pain, joint swelling, palpable masses and mechanical restriction. Whilst giant cell tumour of tendon sheath, pigmented villonodular synovitis, synovial chondromatosis, lipoma arborescens, juxta articular myxomas and inflammatory arthritis are the better-known conditions of the joint. Intra-articular nodular fasciitis, on the other hand, is less well recognized both clinically and radiologically. It is rarely seen in routine practice and is only described in case reports in the literature. Due to the non-specific clinical and radiological findings as well as the unfamiliarity with the entity, the diagnosis of intra-articular nodular fasciitis is usually clinched only after histological examination. We present a case of intra-articular nodular fasciitis arising in the knee joint which was not suspected clinically or radiologically.

  9. A unique case of phaeohyphomycosis subretinal abscess in a patient with arthropathy and lung pathology

    Directory of Open Access Journals (Sweden)

    Bryan J Matthews

    2013-01-01

    Full Text Available A 67-year-old former gold miner with rheumatoid arthritis, treated with steroids and methotrexate, presented to eye casualty with a painful right eye. Examination revealed an anterior uveitis and despite an initial response to topical steroids, the intraocular inflammation worsened with anterior and posterior uveitis development. Re-examination showed a white mass in the peripheral nasal retina initially suspected of being active Toxoplasmosis infection and anti-toxoplasmosis treatment commenced. After improvement and tapering of this treatment, the intraocular inflammation reoccurred. Cytopathological examination of a pars plana vitrectomy obtained vitreous sample that showed a non-diagnostic non-infectious chronic vitritis. The vitreoretinal surgeons elected to do a direct biopsy of the white subretinal mass in the peripheral nasal area. This revealed, quite unexpectedly, an abscess containing pigmented phaeohyphomycosis fungi. This case report documents the multidisciplinary approach that assisted in clinching a final diagnosis and the role of sub-retinal biopsy in this unprecedented scenario.

  10. Bilaterally enlarged parotids and sicca symptoms as a presentation of sarcoidosis: Pivotal role of aspiration cytology in diagnosis

    Directory of Open Access Journals (Sweden)

    Tanya Sharma

    2015-01-01

    Full Text Available Sarcoidosis is a chronic multisystem inflammatory disease of unknown etiology characterized by widespread noncaseating granulomas in various organs. The diagnosis of sarcoidosis is based on cytological, clinicolaboratory, and radiological findings, and requires careful exclusion of other granulomatous diseases especially tuberculosis. Involvement of parotid glands is uncommon. Presentation of sarcoidosis with sicca symptoms that include dryness of eyes and mouth is an even rarer phenomenon. We present a case of multisystemic sarcoidosis presenting with dryness of eyes and mouth along with bilateral enlargement of parotid glands. Fine-needle aspiration cytology (FNAC smears showed epithelioid cell granulomas and multinucleate giant cells. Stain for acid-fast bacilli was negative. Careful cytological examination revealed crystalline structures inside the giant cells, which prompted us to evaluate the patient for sarcoidosis. This case report highlights the cytological features that can be useful in clinching the diagnosis of sarcoidosis in conjunction with clinicoradiological and laboratory findings in a clinically unusual case.

  11. Evaluation of roll-extruded Alloy 718 tubing

    Energy Technology Data Exchange (ETDEWEB)

    Smolik, G R; Korth, G E

    1978-05-01

    A sample of roll-extruded Alloy 718 tubing, a product identified for use in the Clinch River Breeder Reactor, was evaluated. The tubing satisfied AMS 5589 requirements for seamless tubing, and had tensile and fatigue properties comparable to plate for the conventional 955/sup 0/C (1750/sup 0/F) heat treatment. Recrystallization was retarded in this product and bands of very small grains resulted from the conventional heat treatment. Both as-roll-extruded and directly aged material showed the results of thermomechanical processing in high strengths and reductions in area. It is recommended that work continue toward realizing improved fatigue and stress rupture properties in this product by means of ''Minigrain'' and thermomechanical processing. 10 figures, 6 tables.

  12. A Study on Landslide Risk Management by Applying Fault Tree Logics

    Directory of Open Access Journals (Sweden)

    Kazmi Danish

    2017-01-01

    Full Text Available Slope stability is one of the focal areas of curiosity to geotechnical designers and also appears logical for the application of probabilistic approaches since the analysis lead to a “probability of failure”. Assessment of the existing slopes in relation with risks seems to be more meaningful when concerning with landslides. Probabilistic slope stability analysis (PSSA is the best option in covering the landslides events. The intent here is to bid a probabilistic framework for quantified risk analysis with human uncertainties. In this regard, Fault Tree Analysis is utilized and for prediction of risk levels, consequences of the failures of the reference landslides have been taken. It is concluded that logics of fault trees is best fit, to clinch additional categories of uncertainty; like human, organizational, and knowledge related. In actual, the approach has been used in bringing together engineering and management performances and personnel, to produce reliability in slope engineering practices.

  13. Anti-N-Methyl-D-Aspartate Receptor Encephalitis in HIV Infection

    Science.gov (United States)

    Patarata, Eunice; Bernardino, Vera; Martins, Ana; Pereira, Rui; Loureiro, Conceição; Moraes-Fontes, Maria Francisca

    2016-01-01

    Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a rare condition characterized by emotional and behavioral disturbances, dyskinesias, and extrapyramidal signs. It occurs in young women of reproductive age and is classically described as a paraneoplastic phenomenon. We present a 36-year-old, HIV-positive female who was admitted to the hospital in an acute confusional state, with a stiff posture, periods of motor agitation, and myoclonic jerks of the hands. Her mental state progressively deteriorated. Without evidence of infection, the presence of anti-NMDAR antibodies both in serum and cerebrospinal fluid clinched the diagnosis of autoimmune encephalitis. No evidence of neoplastic disease was found, and the beneficial response to immunosuppressive therapy was exceptional. This is the first report of anti-NMDAR encephalitis in an HIV-infected individual, reminding us that autoimmune encephalitis should be included in the differential diagnosis of a young patient presenting in an acute confusional state. PMID:28101036

  14. Advanced reactor safety research quarterly report, October-December 1982. Volume 24

    Energy Technology Data Exchange (ETDEWEB)

    None

    1984-04-01

    This report describes progress in a number of activities dealing with current safety issues relevant to both light water reactors (LWRs) and breeder reactors. The work includes a broad range of experiments to simulate accidental conditions to provide the required data base to understand important accident sequences and to serve as a basis for development and verification of the complex computer simulation models and codes used in accident analysis and licensing reviews. Such a program must include the development of analytical models, verified by experiment, which can be used to predict reactor and safety system performance under a broad variety of abnormal conditions. Current major emphasis is focused on providing information to NRC relevant to (1) its deliberations and decisions dealing with severe LWR accidents and (2) its safety evaluation of the proposed Clinch River Breeder Reactor.

  15. Fatigue Behaviour of Fastening Joints of Sheet Materials and Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    Xiaocong He

    2013-01-01

    Full Text Available Some fastening techniques such as self-piercing riveting, mechanical clinching, and structural adhesive bonding are efficient joining methods which are suitable for joining advanced lightweight sheet materials that are hard to weld. The recent literature relating to fatigue behavior of such fastening joints and finite element analysis is reviewed in this paper. The recent development in fatigue behavior analysis of the fastening joints is described with particular reference to some major factors that influence the fatigue behavior of the fastening joints: failure mechanism, environmental effects, and hybrid joining techniques. The main methods used in finite element analysis of fatigue behavior of the fastening joints of sheet materials are discussed and illustrated with brief case studies from the literature.

  16. Monitored retrievable storage submission to Congress: Volume 2, Environmental assessment for a monitored retrievable storage facility. [Contains glossary

    Energy Technology Data Exchange (ETDEWEB)

    None

    1986-02-01

    This Environmental Assessment (EA) supports the DOE proposal to Congress to construct and operate a facility for monitored retrievable storage (MRS) of spent fuel at a site on the Clinch River in the Roane County portion of Oak Ridge, Tennessee. The first part of this document is an assessment of the value of, need for, and feasibility of an MRS facility as an integral component of the waste management system. The second part is an assessment and comparison of the potential environmental impacts projected for each of six site-design combinations. The MRS facility would be centrally located with respect to existing reactors, and would receive and canister spent fuel in preparation for shipment to and disposal in a geologic repository. 207 refs., 57 figs., 132 tabs.

  17. Renal disease masquerading as pyrexia of unknown origin

    Directory of Open Access Journals (Sweden)

    D Korivi

    2013-01-01

    Full Text Available Pyrexia of unknown origin is a challenging clinical problem. Infections, malignancies, and connective tissue diseases form the major etiologies for this condition. We report a case of a 57-year-old diabetic male who presented with fever of unknown origin for several months. The course of investigations led to a kidney biopsy which clinched the cause of his fever as well as the underlying diagnosis. The light microscopy findings of expansile storiform fibrosis with a dense inflammatory infiltrate suggested the diagnosis which was confirmed by positive staining of Immunoglobulin G4, the dense lympho-plasmacytic infiltrate and elevated serum IgG4 concentrations. A course of steroids followed by mycophenolate mofetil as maintenance immunosuppression rendered the patient afebrile with improvement of renal function.

  18. External jugular venous aneurysm: A clinical curiosity

    Science.gov (United States)

    Mohanty, Debajyoti; Jain, Bhupendra Kumar; Garg, Pankaj Kumar; Tandon, Anupama

    2013-01-01

    Jugular venous aneurysm is an extremely rare condition. The patients presented with a painless swelling in the neck that appears while coughing, straining, bending, or breath holding. Detection of a soft and compressible swelling in the course of an external jugular vein (EJV) superficial to the sternomastoid muscle, non-filling on compression of the EJV during Valsalva maneuver clinches the diagnosis of EJV aneurysm. Color Doppler ultrasound allows precise delineation of the lesion and is considered the gold standard for confirming the diagnosis. Surgical excision is indicated mostly for cosmetic reasons and symptomatic aneurysms. We, herein, report a patient with saccular external jugular venous aneurysm to highlight the typical clinical presentation and diagnosis of this rare entity. PMID:23633867

  19. Arthroscopic Management of Pigmented Villonodular Synovitis of the Knee Joint.

    Science.gov (United States)

    Dwidmuthe, Samir; Barick, Devashis; Rathi, Tarun

    2015-01-01

    Pigmented Villonodular Synovitis (PVNS) of knee joint is a rare disorder of Synovium. Hip and knee joint are commonly affected joints. The knee PVNS presents as a localized or diffuse form. Diagnosis if often delayed and permanent joint damage occurs with advanced disease. Ultrasound examination shows fluid collection and synovial hypertrophy. Magnetic resonance imaging helps in clinching the diagnosis. Final confirmation of PVNS is done with histopathological examination of synovial tissue removed. Post operative radiation has shown to reduce the rate of recurrent disease. 25 years male presented to us with painless swelling of left knee joint of 3 months duration. Radiographs were normal. MRI showed synovial hypertrophy with changes suggestive of PVNS. We did arthroscopic six portal synovectomy. The patient regained his function and was asymptomatic at 2 year follow up. We want to emphasize that early diagnosis and well done arthroscopic Synovectomy gives good clinical outcome with low recurrence rate. Radiotherapy should be reserved for recurrent disease.

  20. Medium-range containerships making much headway%中型集装箱船大行其道

    Institute of Scientific and Technical Information of China (English)

    宋洋

    2005-01-01

    In the first 5 months of 2004, the transaction of the containerships worldwide continued maintaining a strong momentum. Among them, those medium-sized and small-sized containerships under 3000 TUE were clinched, totaling 85 units, up to 2.1 million dwt. These particular type of containerships have enjoyed substantial appreciation in the markets for reselling both the second-handed ships and new buildings since the second half of 2000. According to the statistics from the ship leasing market, the leasing rate for the medium-sized containerships has already topped its past records popped up in the third quarter of 2000. Likewise, the pricing of the small-and medium-sized containerships to be ordered has also exceeded its record high.

  1. Parry-Romberg syndrome with hemimasticatory spasm in pregnancy; A dystonia mimic

    Directory of Open Access Journals (Sweden)

    Akhila Kumar Panda

    2014-01-01

    Full Text Available Parry-Romberg syndrome (PRS with hemimasticatory spasm (HMS is quite an uncommon overlapping phenomenon which very often mimics jaw closing dystonia. A previously healthy 35-year-old female, during her 5 th month of pregnancy started developing intermittent unilateral painful spasms of jaw while conversation, clinching of teeth, or eating, which led to frequent tongue bites. The spasms were worsened during pregnancy. She used to do certain manoeuvre like sensory tricks in form of touching involved side of the face to relieve the symptoms. Apart from this, she developed progressive hemifacial and hemitongue atrophy. Other medical and neurological examinations were normal. Laboratory investigations as well as neuroimaging were noncontributory. The spasm responded to carbamazepine but hemifacial atrophy persists. To our best knowledge, onset and worsening of this syndrome in pregnancy has not been described earlier which might be correlated either with some hormonal imbalance or some unknown mechanisms.

  2. Granuloma multiforme: A report from India

    Directory of Open Access Journals (Sweden)

    Kumari Rashmi

    2009-01-01

    Full Text Available Granuloma multiforme (GM is a reactive skin disorder of unknown etiology, characterized clinically by confluent annular lesions and histologically by focal necrobiosis and histiocytic granulomas. GM is significant because of its clinical resemblance to tuberculoid leprosy, with which it can be confused. Here, we report a case of granuloma multiforme from India in a 70-year-old male farmer, with multiple asymptomatic large annular rings of papules over the back and thighs on photodistributed sites. Histopathology helps to clinch the diagnosis and differentiate from similar clinical and histologic mimics such as granuloma annulare, tuberculoid leprosy, actinic granuloma and annular sarcoid. Nevertheless, a very high degree of suspicion is required to diagnose GM.

  3. Assessment of CRBR core disruptive accident energetics

    Energy Technology Data Exchange (ETDEWEB)

    Theofanous, T.G.; Bell, C.R.

    1984-03-01

    The results of an independent assessment of core disruptive accident energetics for the Clinch River Breeder Reactor are presented in this document. This assessment was performed for the Nuclear Regulatory Commission under the direction of the CRBR Program Office within the Office of Nuclear Reactor Regulation. It considered in detail the accident behavior for three accident initiators that are representative of three different classes of events; unprotected loss of flow, unprotected reactivity insertion, and protected loss of heat sink. The primary system's energetics accommodation capability was realistically, yet conservatively, determined in terms of core events. This accommodation capability was found to be equivalent to an isentropic work potential for expansion to one atmosphere of 2550 MJ or a ramp rate of about 200 $/s applied to a classical two-phase disassembly.

  4. Does IFRS Detract from Social Disclosure in Corporate Annual Report and Accounts? Evidence from Nigeria

    Directory of Open Access Journals (Sweden)

    Arthur Joseph Avwokeni

    2016-10-01

    Full Text Available This study examines compliance with the corporate social disclosure requirement of the United Nations and whether their voluntary declaration by the International Accounting Standards Board detracts from compliance. Qualitative, financial and non-financial disclosures, based on core indicators developed by the United Nations Conference on Trade, Aid and Development, were garnered from financial statements prepared before and after IFRS adoption. Overall, corporate social disclosure on employment creation and labour practices; welfare, health and safety; and environment, improve during the IFRS regime. This improvement is associated with size of the firm, not audit identity, ownership or capital structure. This finding provides evidence to clinch anecdotal claims that even in the absence of laws some agents would still operate to meet the information needs of their principals; however, in line with organization theory, policies are needed to guide the actions of man, including the learning organization.

  5. Disseminated histoplasmosis in an immunocompetent haweli dweller: A diagnosis and follow-up by endoscopic ultrasound-guided fine-needle aspiration

    Directory of Open Access Journals (Sweden)

    Ruth Shifa Ecka

    2015-01-01

    Full Text Available Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA is nowadays widespread minimally invasive procedure for diagnosing a large number of benign as well as malignant lesions. We report a case of a 62-year-old immunocompetent elderly male, who presented with high-grade fever, hepatosplenomegaly and mediastinal and intra-abdominal lymph nodes. He was residing in an old haweli with bats infestation. EUS-FNA of the subcarinal and the preaortic lymph node clinched the diagnosis. A rapid on-site evaluation of the cytology material revealed organisms conforming to the morphology of Histoplasma capsulatum. The patient was immediately started on amphotericin B and itraconazole and responded well. In this case, we found the role of EUS-FNA not only in diagnosis, but also in the follow-up of the patient.

  6. Hepatic angiomyolipoma: A case report with diagnostic challenge

    Directory of Open Access Journals (Sweden)

    Ashumi Gupta

    2013-01-01

    Full Text Available Angiomyolipomas are rare benign tumors derived from perivascular epithelioid cells that occur frequently in kidney and rarely in the liver. We present a case of hepatic angiomyolipma, with various clinical and radiological differential diagnoses. A 34-year-old male was found to have a palpable mass on the left side of the abdomen. Imaging showed heterogeneously enhancing mass lesion 15 cm Χ 7 cm, in the left lobe and segment 4 of the liver. Various benign and malignant diagnoses were entertained. The needle biopsy did not reveal any evidence of malignancy. Patient underwent resection of the lesion in view of the large size, which was diagnosed as angiomyolipoma. Angiomyolipoma is a benign tumor and accurate diagnosis is important to prevent overtreatment. Histology and immunohistochemisry may help in clinching the diagnosis, in proper clinical setting.

  7. Simulation of a Novel Joining Process for Fiber-Reinforced Thermoplastic Composites and Metallic Components

    Science.gov (United States)

    Gude, M.; Freund, A.; Vogel, C.; Kupfer, R.

    2017-01-01

    In this study, a new joining technology to produce hybrid structures with continuous-fiber-reinforced thermoplastics and metallic components is presented adapting the concept of classical clinching for thermoplastic composites. To demonstrate the capability of the thermoclinching process, prototypic joints were manufactured using an experimental joining installation developed. Nondestructive and destructive analyses of the thermoclinched joints showed that a relocation of the reinforcement into the neck and head area of the joining zone could be achieved. For a first estimation of the maximum load-carrying capacity of the joints, single-lap specimens with both reinforced and nonreinforced thermoplastics were manufactured and tested, revealing up to 50% higher failure loads of the reinforced joints. To understand the local material configuration and to achieve a defined and adjustable fabric structure in the head area of the joint, further analyses with regard to material- and tool-side conditions of the joining zone are necessary.

  8. Sodium and NaK spills: cleanup and disposal of wastes for the CRBRP

    Energy Technology Data Exchange (ETDEWEB)

    Welch, F. H.

    1978-01-01

    Massive sodium or NaK spills have been postulated for the Clinch River Breeder Reactor Plant storage vessels. This report investigates various methods of removing the sodium or NaK and how these methods apply to selected accident situations. The accident by products and the products of the removal operation are discussed relative to their hazards and disposal in both nonfire and fire situations. Removal procedures are presented for four spill situations, including a special case where a 35,000-gal spill of radioactive sodium occurs in cell 102A when the cell is air filled and open to the reactor containment building (RCB). The resulting fire spreads sodium oxidation product aerosols throughout cell 102A and the RCB.

  9. Neuroleptic malignant syndrome masked by cerebral malaria.

    Science.gov (United States)

    Rajesh, Kumar Muniandy; Sinnathamby, Vellan; Sakthi, Arul N

    2013-05-22

    A 38-year-old man with an underlying psychiatric illness presented with altered sensorium and abnormal behaviour. He was febrile at 38°C and weak looking; otherwise no other abnormalities were detected. A blood film conducted for malarial parasite (BFMP) revealed Plasmodium falciparum; hence a diagnosis of cerebral malaria was made. He was treated with antimalarial drugs for 2 days prior to being transferred out to the ward following clinical improvement. He subsequently developed episodes of stupor and refusal of feeding. Following an evaluation by the psychiatrist, a diagnosis of catatonic schizophrenia was made and he was started on oral sulpiride and benhexol. Unfortunately, he developed high-grade fever at 40°C with muscle rigidity and fasciculation. The diagnosis of neuroleptic malignant syndrome (NMS) was clinched and the antipsychotics were discontinued. However he succumbed to NMS several days later due to multiorgan failure.

  10. Essays on Market Design

    DEFF Research Database (Denmark)

    Liu, Yun

    popular multi-unit auction rules: uniform-price auction (UPA) and discriminatory-price auction (DPA). I characterize the set of asymmetric monotone Bayes–Nash equilibria in a simple multi-unit auction game in which two units of a homogeneous object are auctioned among a set of bidders. I argue...... that bidders’ strategic behavior essentially comes from their diverse market positions (i.e., the winning probability and the probability of deciding the market-clearing price). That is, if a bidder has a relatively strong market position, she has less incentive to shade her bid for the second unit in a UPA......-member payoff and the core-stability. In the last chapter, I show that a variant of the Vickrey-Clarke-Groves auction, Ausubel’s clinching auction, is vulnerable to collusion in the sense that it always has a nonempty core. I further discuss an isomorphism relation between group strategy-proofness and non...

  11. Oak Ridge Reservation Federal Facility agreement quarterly report for the Environmental Restoration Program, January--March 1994. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This quarterly progress report satisfies requirements for the Environmental Restoration (ER) Program that are specified in the Oak Ridge Reservation (ORR) Federal Facility Agreement (FFA) established between the US Department of Energy (DOE), the US Environmental Protection Agency (EPA), and the Tennessee Department of Environment and Conservation (TDEC). The reporting period covered herein is January through March 1994 (second quarter of FY 1994). Sections 1.1 and 1.2 provide respectively the milestones scheduled for completion during the reporting period and a list of documents that have been proposed for transmittal during the following quarter but have not been approved as FY 1994 commitments. Section 2 covers significant accomplishments. Section 3 discusses technical status at the Oak Ridge Y-12 Plant, Oak Ridge National Laboratory, Oak Ridge K-25 Site, and Clinch River. Technical oversight and technical programs are also covered. Section 4 covers responds action contractor assignments.

  12. A Curious Case of Acute Respiratory Failure: Is It Antisynthetase Syndrome?

    Directory of Open Access Journals (Sweden)

    Gurveen Malhotra

    2016-01-01

    Full Text Available Antisynthetase (AS syndrome is a major subgroup of inflammatory myopathies seen in a minority of patients with dermatomyositis and polymyositis. Although it is usually associated with elevated creatine phosphokinase level, some patients may have amyopathic dermatomyositis (ADM like presentation with predominant skin involvement. Interstitial lung disease (ILD is the main pulmonary manifestation and may be severe thereby determining the prognosis. It may rarely present with a very aggressive course resulting in acute respiratory distress syndrome (ARDS. We report a case of a 43-year-old male who presented with nonresolving pneumonia who was eventually diagnosed to have ADM through a skin biopsy without any muscle weakness. ADM may be associated with rapidly progressive course of interstitial lung disease (ADM-ILD which is associated with high mortality. Differentiation between ADM-ILD and AS syndrome may be difficult in the absence of positive serology and clinical presentation may help in clinching the diagnosis.

  13. Tennessee health studies agreement. Annual report for year 5, January 1--December 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    This report summarizes the Oak Ridge Health Studies project for the period January 1, 1996, to December 31, 1996. Attention is focused on dose reconstruction which is comprised of seven separate tasks. They are: Task 1, investigation of radioiodine from radioactive lanthanum processing; Task 2, investigation of mercury releases from lithium enrichment; Task 3, investigation of releases of PCBs from Oak Ridge facilities; Task 4, investigation of releases of radionuclides from White Oak Creek to the Clinch River; Task 5, plan to perform a systematic document search; Task 6, investigation of the quality of historical uranium effluent monitoring of Oak Ridge facilities; and Task 7, additional screening of materials not evaluated in the dose reconstruction feasibility study.

  14. Unusual orbital foreign bodies

    Directory of Open Access Journals (Sweden)

    Agarwal P

    1993-01-01

    Full Text Available Retained intraorbital organic foreign bodies, particularly wooden, are commonly encountered in ophthalmologic practice. We treated two children who had sustained such injury while playing. They presented to us with non-healing sinus with purulent discharge. In one of the patients, X-rays and CT scan helped to clinch the diagnosis, whereas in the other patient diagnosis was possible by correlating history with clinical findings. Surgical exploration in both patients helped us to remove the foreign bodies. Surprisingly, both the foreign bodies were 7 cm long wooden pieces. We, however, caution that management of such cases should be conservative and that surgical exploration be done only in case of complication. From our experience, we recommend proper localisation by all possible means, blunt dissection, careful haemostasis coupled with excellent lighting and exposure in the atraumatic removal of intraorbital foreign bodies.

  15. RARE PRESENTATION OF RUPTURED RUDIMENTARY HORN PREGNANCY

    Directory of Open Access Journals (Sweden)

    Shergill Harbhajan K, Grover Suparna, Chhabra Ajay

    2015-10-01

    Full Text Available It is a rare occurrence for the rudimentary horn of uterus to harbour a pregnancy and the usual outcome is devastating leading to a spontaneous rupture in second trimester with the patient presenting in shock with massive intra-peritoneal haemorrhage and if appropriate management is not instituted in time it may lead to high rate of mortality. We report an unusual case of rupture rudimentary horn pregnancy who presented as a chronic ectopic with an adnexal mass and surprisingly with no sign of shock. Diagnosis is often difficult in such a situation which puts the treating gynaecologist in dilemma. High clinical suspicion supplemented with radiological findings helped clinch the diagnosis and laparotomy was performed followed by resection of the rudimentary horn to prevent future complications.

  16. From Hearing Aids, Prostheses and Cochlear Implants to "Bionic" Feedback Phonation

    Directory of Open Access Journals (Sweden)

    Petros Stagiopoulos

    2016-08-01

    Full Text Available In Otorhinolaryngological medical practice therapeutic devices are used that are highly invasive and immersive. For aural and oral communication these could be hearing aids, prosthetics, implants or radio-electronic appliances that build up a bionic environment with apparent tendencies for virtualization. The popularization of such devices promotes the extensive use of Brain Computer Interfaces to both the scientific community and the consumer market. The use of bionic devices clinched with synapses of the nerves does not merely mingle input activity to brain activity, but also it provides a virtual channel for augmenting and manipulating speech communication, language communication and even further musical communication. The effects of bionic aural and oral communication when learning practices for the impaired in hearing are applied is encountered in terms of ability for speech perception and linguistic competence

  17. EVALUATING THE EFFECTS OF FLY ASH EXPOSURE ON FISH EARLY LIFE STAGES: FATHEAD MINNOW EMBRYO-LARVAL TESTS

    Energy Technology Data Exchange (ETDEWEB)

    Greeley Jr, Mark Stephen [ORNL; Elmore, Logan R [ORNL; McCracken, Kitty [ORNL

    2012-05-01

    On December 22, 2008, a dike containing fly ash and bottom ash in an 84-acre complex of the Tennessee Valley Authority's (TVA) Kingston Steam Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits extended as far as 4 miles upstream (Emory River mile 6) of the Plant, and some ash was carried as far downstream as Tennessee River mile 564 ({approx}4 miles downstream of the Tennessee River confluence with the Clinch River). A byproduct of coal burning power plants, fly ash contains a variety of metals and other elements which, at sufficient concentrations and in specific forms, can be toxic to biological systems. The effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to be the effects of specific ash constituents, especially selenium, on fish early life stages. Uptake by adult female fish of fly ash constituents through the food chain and subsequent maternal transfer of contaminants to the developing eggs is thought to be the primary route of selenium exposure to larval fish (Woock and others 1987, Coyle and others 1993, Lemly 1999, Moscatello and others 2006), but direct contact of the fertilized eggs and developing embryos to ash constituents in river water and sediments is also a potential risk factor (Woock and others 1987, Coyle and others 1993, Jezierska and others 2009). To address the risk of fly ash from the Kingston spill to the reproductive health of downstream fish populations, ORNL has undertaken a series of studies in collaboration with TVA including: (1) a field study of the bioaccumulation of fly ash constituents in fish ovaries and the reproductive condition of sentinel fish species in reaches of the Emory and Clinch Rivers affected by the fly ash spill; (2) laboratory tests of the potential toxicity of fly ash from the spill area on fish embryonic and larval development (reported in the

  18. Oak Ridge Dose Reconstruction annual report for calendar year 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    Calendar year 1997 was the third full year of work on the Oak Ridge Dose Reconstruction. Activities are summarized on the following individual project tasks: Task 1 -- Investigation of radioiodine releases from X-10 radioactive lanthanum processing; Task 2 -- Investigation of mercury releases from Y-12 lithium enrichment; Task 3 -- Investigation of PCBs in the environment near Oak Ridge; Task 4 -- Investigation of radionuclides released from White Oak Creek to the Clinch River; Task 5 -- Systematic searching of records repositories; Task 6 -- Evaluation of the quality of uranium monitoring data and a screening evaluation of potential off-site health risks; and Task 7 -- Performance of screening for additional materials not evaluated in the feasibility study.

  19. Acute toxic effects of two lampricides on twenty-one freshwater invertebrates

    Science.gov (United States)

    Rye, Robert P.; King, Everett Louis

    1976-01-01

    We conducted laboratory static bioassays to determine acute toxicity of two lampricides -- a 70% 2-aminoethanol salt of 5,2'dichloro-4'-nitrosalicylanilide (Bayer 73) and a mixture containing 98% 3-trifluoromethyl-4-nitrophenol (TFM) and 2% Bayer 73 (TFM-2B) -- to 21 freshwater invertebrates. LC50 values were determined for 24-h exposure periods at 12.8 C. Organisms relatively sensitive to Bayer 73 were a turbellarian (Dugesia tigrina), aquatic earthworms (Tubifex tubifex and Lumbriculus inconstans), snails (Physa sp.) and (Pleurocera sp.), a clam (Eliptio dilatatus), blackflies (Simulium sp.), leeches (Erpobdellidae), and a daphnid (Daphnia pulex). The invertebrates most sensitive to TFM-2B were turbellarians, aquatic earthworms (Tubifex), snails (Physa), blackflies, leeches, and burrowing mayflies (Hexagenia sp.). Bayer 73 was generally much more toxic to the test organisms than TFM-2B. At lampricidal concentrations, TFM-2B was more highly selective than Bayer 73 against larval sea lampreys (Petromyzon marinus).

  20. Strategies for Transferring Mixtures of Organic Contaminants from Aquatic Environments into Bioassays

    DEFF Research Database (Denmark)

    Jahnke, Annika; Mayer, Philipp; Schäfer, Sabine

    2016-01-01

    into bioassays, while conserving (or re-establishing) their chemical composition at adjustable levels for concentration-effect assessment. This article outlines various strategies for quantifiable transfer from environmental samples including water, sediment, and biota into bioassays using total extraction...... and monitoring of such mixtures, a variety of cell-based in vitro and low-complexity in vivo bioassays based on algae, daphnids or fish embryos are available. A very important and sometimes unrecognized challenge is how to combine sampling, extraction and dosing to transfer the mixtures from the environment......Mixtures of organic contaminants are ubiquitous in the environment. Depending on their persistence and physicochemical properties, individual chemicals that make up the mixture partition and distribute within the environment and might then jointly elicit toxicological effects. For the assessment...

  1. The Effects of Natural and Anthropogenic Microparticles on Individual Fitness in Daphnia magna.

    Directory of Open Access Journals (Sweden)

    Martin Ogonowski

    Full Text Available Concerns are being raised that microplastic pollution can have detrimental effects on the feeding of aquatic invertebrates, including zooplankton. Both small plastic fragments (microplastics, MPs produced by degradation of larger plastic waste (secondary MPs; SMPs and microscopic plastic spheres used in cosmetic products and industry (primary MPs; PMPs are ubiquitously present in the environment. However, despite the fact that most environmental MPs consist of weathered plastic debris with irregular shape and broad size distribution, experimental studies of organism responses to MP exposure have largely used uniformly sized spherical PMPs. Therefore, effects observed for PMPs in such experiments may not be representative for MP-effects in situ. Moreover, invertebrate filter-feeders are generally well adapted to the presence of refractory material in seston, which questions the potential of MPs at environmentally relevant concentrations to measurably affect digestion in these organisms. Here, we compared responses to MPs (PMPs and SMPs and naturally occurring particles (kaolin clay using the cladoceran Daphnia magna as a model organism. We manipulated food levels (0.4 and 9 μg C mL-1 and MP or kaolin contribution to the feeding suspension (<1 to 74% and evaluated effects of MPs and kaolin on food uptake, growth, reproductive capacity of the daphnids, and maternal effects on offspring survival and feeding. Exposure to SMPs caused elevated mortality, increased inter-brood period and decreased reproduction albeit only at high MP levels in the feeding suspension (74% by particle count. No such effects were observed in either PMP or kaolin treatments. In daphnids exposed to any particle type at the low algal concentration, individual growth decreased by ~15%. By contrast, positive growth response to all particle types was observed at the high algal concentration with 17%, 54% and 40% increase for kaolin, PMP and SMP, respectively. When test particles

  2. Comparative toxicity of methanol and N,N-dimethylformamide to freshwater fish and invertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, S.H.; Knuth, M.L.; Anderson-Buchou, C.D.; Brooke, L.T.; Lima, A.R.; Shubat, P.J.

    1986-10-01

    The organic solvents methanol and N,N-dimethylformamide (DMF) are used widely as industrial solvents. Although some toxicity data appear in the literature for methanol and DMF, there have been few studies which have been flow-through tests for a standard 48- or 96-h exposure period with measured toxicant concentrations. In this study, 96-h flow-through acute toxicity tests with methanol and DMF were conducted with three species of freshwater fish - rainbow trout (Salmo gairdneri), bluegill (Lepomis macrochirus) and fathead minnow (Pimephales promelas). Static acute toxicity tests (48 h) were conducted with DMF and two species of freshwater invertebrates - a midge (Paratanytarsus parthenogeneticus) and a daphnid (Daphnia magna). Median lethal (LC50) and median effect (EC50) concentrations for 96-h exposures were determined for fish and 48-h EC50's were determined for invertebrates.

  3. Occurrence, seasonal variation and risk assessment of antibiotics in the reservoirs in North China.

    Science.gov (United States)

    Li, Nan; Zhang, Xinbo; Wu, Wei; Zhao, Xinhua

    2014-09-01

    The occurrence and seasonal variability of five groups (tetracycline, quinolone, chloramphenicol, macrolide and sulfonamide) of antibiotics were investigated in the surface water of four reservoirs. The dissolved concentrations of 29 antibiotics were in the ngL(-1) level. Trace levels of all target antibiotics were analyzed using solid-phase extraction followed by liquid chromatography electrospray tandem mass spectrometry. All of the antibiotics were detected at all sampling sites, indicating widespread occurrence of antibiotics in the study area. The detection of florfenicol, josamycin, kitasamycin, spiramycin and sulfameter is the first report of these compounds in reservoir samples. The results showed an association between the presence of some antibiotics at Panjiakou reservoir and cage culture of fish. Twenty-three types of antibiotics showed significant seasonal variations (pantibiotics detected could cause very low risk to algae, daphnid and fish. Further health risk need to be investigated because these reservoirs are drinking water sources.

  4. Acute Toxicity and Environmental Risks of Five Veterinary Pharmaceuticals for Aquatic Macroinvertebrates.

    Science.gov (United States)

    Bundschuh, Mirco; Hahn, Torsten; Ehrlich, Bert; Höltge, Sibylla; Kreuzig, Robert; Schulz, Ralf

    2016-02-01

    Due to the high use of antibiotics and antiparasitics for the treatment of livestock, there is concern about the potential impacts of the release of these compounds into freshwater ecosystems. In this context, the present study quantified the acute toxicity of two antibiotics (sulfadiazine and sulfadimidine), and three antiparasitic agents (flubendazole, fenbendazole, ivermectin) for nine freshwater invertebrate species. These experiments revealed a low degree of toxicity for the sulfonamide antibiotics, with limited implications in the survival of all test species at the highest test concentrations (50 and 100 mg/L). In contrast, all three antiparasitic agents indicated on the basis of their acute toxicity risks for the aquatic environment. Moreover, chronic toxicity data from the literature for antiparasitics, including effects on reproduction in daphnids, support the concern about the integrity of aquatic ecosystems posed by releases of these compounds. Thus, these pharmaceuticals warrant further careful consideration by environmental risk managers.

  5. Analysis of expressed sequence tags of the water flea Daphnia magna.

    Science.gov (United States)

    Watanabe, Hajime; Tatarazako, Norihisa; Oda, Shigeto; Nishide, Hiroyo; Uchiyama, Ikuo; Morita, Masatoshi; Iguchi, Taisen

    2005-08-01

    To study gene expression in the water flea Daphnia magna we constructed a cDNA library and characterized the expressed sequence tags (ESTs) of 7210 clones. The EST sequences clustered into 2958 nonredundant groups. BLAST analyses of both protein and DNA databases showed that 1218 (41%) of the unique sequences shared significant similarities to known nucleotide or amino acid sequences, whereas the remaining 1740 (59%) showed no significant similarities to other genes. Clustering analysis revealed particularly high expression of genes related to ATP synthesis, structural proteins, and proteases. The cDNA clones and EST sequence information should be useful for future functional analysis of daphnid biology and investigation of the links between ecology and genomics.

  6. Assessment of landfill leachate toxicity reduction after biological treatment.

    Science.gov (United States)

    Jemec, Anita; Tišler, Tatjana; Zgajnar-Gotvajn, Andreja

    2012-02-01

    In the present article, the efficiency of biological treatment of landfill leachates was evaluated by implementation of physicochemical characterisation and a complex toxicity assessment. An array of toxicity tests using bacterium Vibrio fischeri, alga Desmodesmus subspicatus, crustacean Daphnia magna, and embryo of fish Danio rerio, as well as unconventional methods using biochemical biomarkers (protein content, enzymes cholinesterase, and glutathione-S-transferase), were employed. Toxicity of leachates varied depending on the season of collection in relation to their different physicochemical characteristics. Uncommon effects of leachates on organisms, such as hormetic-like increases of algal growth and reproduction of daphnids, were identified. New approaches using the activities of enzymes were found unsuitable for routine hazard assessment of leachates. Although physicochemical parameters and toxicity decreased significantly after biological treatment, the effluents did not meet the demands of the current Slovenian legislation; thus, the existing biological treatment was found inappropriate. The development of advanced treatment techniques for landfill leachates is thus encouraged.

  7. Comparison of solid-phase and eluate assays to gauge the ecotoxicological risk of organic wastes on soil organisms.

    Science.gov (United States)

    Domene, Xavier; Alcañiz, Josep M; Andrés, Pilar

    2008-02-01

    Development of methodologies to assess the safety of reusing polluted organic wastes in soil is a priority in Europe. In this study, and coupled with chemical analysis, seven organic wastes were subjected to different aquatic and soil bioassays. Tests were carried out with solid-phase waste and three different waste eluates (water, methanol, and dichloromethane). Solid-phase assays were indicated as the most suitable for waste testing not only in terms of relevance for real situations, but also because toxicity in eluates was generally not representative of the chronic effects in solid-phase. No general correlations were found between toxicity and waste pollutant burden, neither in solid-phase nor in eluate assays, showing the inability of chemical methods to predict the ecotoxicological risks of wastes. On the contrary, several physicochemical parameters reflecting the degree of low organic matter stability in wastes were the main contributors to the acute toxicity seen in collembolans and daphnids.

  8. Strategies for Transferring Mixtures of Organic Contaminants from Aquatic Environments into Bioassays.

    Science.gov (United States)

    Jahnke, Annika; Mayer, Philipp; Schäfer, Sabine; Witt, Gesine; Haase, Nora; Escher, Beate I

    2016-06-07

    Mixtures of organic contaminants are ubiquitous in the environment. Depending on their persistence and physicochemical properties, individual chemicals that make up the mixture partition and distribute within the environment and might then jointly elicit toxicological effects. For the assessment and monitoring of such mixtures, a variety of cell-based in vitro and low-complexity in vivo bioassays based on algae, daphnids or fish embryos are available. A very important and sometimes unrecognized challenge is how to combine sampling, extraction and dosing to transfer the mixtures from the environment into bioassays, while conserving (or re-establishing) their chemical composition at adjustable levels for concentration-effect assessment. This article outlines various strategies for quantifiable transfer from environmental samples including water, sediment, and biota into bioassays using total extraction or polymer-based passive sampling combined with either solvent spiking or passive dosing.

  9. Effect of linear alkylbenzene sulfonate on population growth of Daphnia galeata: a life table evaluation.

    Science.gov (United States)

    Tanaka, Y; Nakanishi, J

    2001-01-01

    The chronic effect of linear alkylbenzene sulfonate (LAS12) on a daphnid species (Daphnia galeata) was examined by the life table experiment. The estimated responses in the intrinsic rate of population growth r were analyzed with two alternate concentration-response functions, i.e., the power function and the quadratic function. Based on the best-fit power function model with biases corrected by the jackknife procedure, the population-level EC50, which is defined as the concentration of chemicals that reduces the population growth rate (the intrinsic rate of natural increase) by 50%, was estimated as 2.5 mg/L. The 48-h acute immobility test yielded EC50 of 4.6 mg/L. The population-level effect of LAS12 on this test species is considerably more sensitive than the acute lethal effects to neonates.

  10. Toxicity and bioaccumulation of xenobiotic organic compounds in the presence of aqueous suspensions of aggregates of nano-C60

    DEFF Research Database (Denmark)

    Baun, Anders; Sørensen, Sara Nørgaard; Rasmussen, R.F.

    2008-01-01

    The potential of C60-nanoparticles (Buckminster fullerenes) as contaminant carriers in aqueous systems was studied in a series of toxicity tests with algae (Pseudokirchneriella subcapitata) and crustaceans (Daphnia magna). Four common environmental contaminants (atrazine, methyl parathion...... in 4-days-old D. magna was studied with and without addition of C60 in aqueous suspensions. It was found that 85% of the added phenanthrene sorbed to C60-aggregates >200nm whereas about 10% sorption was found for atrazine, methyl parathion, and pentachlorophenol. In algal tests, the presence of C60...... as water phase concentrations. Thus, results from both toxicity tests show that phenanthrene sorbed to C60-aggregates is available for the organisms. For atrazine and methyl parathion no statistically significant differences in toxicities could be observed in algal and daphnid tests as a result...

  11. Environmental impacts of the Tennessee Valley Authority Kingston coal ash spill. 2. Effect of coal ash on methylmercury in historically contaminated river sediments.

    Science.gov (United States)

    Deonarine, Amrika; Bartov, Gideon; Johnson, Thomas M; Ruhl, Laura; Vengosh, Avner; Hsu-Kim, Heileen

    2013-02-19

    The Tennessee Valley Authority Kingston coal ash spill in December 2008 deposited approximately 4.1 million m(3) of fly ash and bottom ash into the Emory and Clinch River system (Harriman, Tennessee, U.S.A.). The objective of this study was to investigate the impact of the ash on surface water and sediment quality over an eighteen month period after the spill, with a specific focus on mercury and methylmercury in sediments. Our results indicated that surface water quality was not impaired with respect to total mercury concentrations. However, in the sediments of the Emory River near the coal ash spill, total mercury concentrations were 3- to 4-times greater than sediments several miles upstream of the ash spill. Similarly, methylmercury content in the Emory and Clinch River sediments near the ash spill were slightly elevated (up to a factor of 3) at certain locations compared to upstream sediments. Up to 2% of the total mercury in sediments containing coal ash was present as methylmercury. Mercury isotope composition and sediment geochemical data suggested that elevated methylmercury concentrations occurred in regions where native sediments were mixed with coal ash (e.g., less than 28% as coal ash in the Emory River). This coal ash may have provided substrates (such as sulfate) that stimulated biomethylation of mercury. The production of methylmercury in these areas is a concern because this neurotoxic organomercury compound can be highly bioaccumulative. Future risk assessments of coal ash spills should consider not only the leaching potential of mercury from the wastes but also the potential for methylmercury production in receiving waters.

  12. Field sampling and analysis plan for the remedial investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Boston, H.L.; Ashwood, T.L.; Borders, D.M.; Chidambariah, V.; Downing, D.J.; Fontaine, T.A.; Ketelle, R.H.; Lee, S.Y.; Miller, D.E.; Moore, G.K.; Suter, G.W.; Tardiff, M.F.; Watts, J.A.; Wickliff, D.S.

    1992-02-01

    This field sampling and analysis (S & A) plan has been developed as part of the Department of Energy`s (DOE`s) remedial investigation (RI) of Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL) located in Oak Ridge, Tennessee. The S & A plan has been written in support of the remedial investigation (RI) plan for WAG 2 (ORNL 1990). WAG 2 consists of White Oak Creek (WOC) and its tributaries downstream of the ORNL main plant area, White Oak Lake (WOL), White Oak Creek embayment (WOCE) on the Clinch River, and the associated floodplain and subsurface environment (Fig. 1.1). The WOC system is the surface drainage for the major ORNL WAGs and has been exposed to a diversity of contaminants from operations and waste disposal activities in the WOC watershed. WAG 2 acts as a conduit through which hydrologic fluxes carry contaminants from upgradient areas to the Clinch River. Water, sediment, soil, and biota in WAG 2 are contaminated and continue to receive contaminants from upgradient WAGs. This document describes the following: an overview of the RI plan, background information for the WAG 2 system, and objectives of the S & A plan; the scope and implementation of the first 2 years of effort of the S & A plan and includes recent information about contaminants of concern, organization of S & A activities, interactions with other programs, and quality assurance specific to the S & A activities; provides details of the field sampling plans for sediment, surface water, groundwater, and biota, respectively; and describes the sample tracking and records management plan.

  13. Waste Area Grouping 2 Remedial Investigation Phase 1 Seep Task data report: Contaminant source area assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hicks, D.S.

    1996-03-01

    This report presents the findings of the Waste Area Grouping (WAG) 2, Phase 1 Remedial Investigation (RI) Seep Task efforts during 1993 and 1994 at Oak Ridge National Laboratory (ORNL). The results presented here follow results form the first year of sampling, 1992, which are contained in the Phase 1 RI report for WAG 2 (DOE 1995a). The WAG 2 Seep Task efforts focused on contaminants in seeps, tributaries, and main streams within the White Oak Creek (WOC) watershed. This report is designed primarily as a reference for contaminants and a resource for guiding remedial decisions. Additional in-depth assessments of the Seep Task data may provide clearer understandings of contaminant transport from the different source areas in the WOC watershed. WAG 2 consists of WOC and its tributaries downstream of the ORNL main plant area, White Oak Lake, the White Oak Creek Embayment of the Clinch River, and the associated flood plains and subsurface environment. The WOC watershed encompasses ORNL and associated WAGs. WAG 2 acts as an integrator for contaminant releases from the contaminated sites at ORNL and as the conduit transporting contaminants to the Clinch River. The main objectives of the Seep Task were to identify and characterize seeps, tributaries and source areas that are responsible for the contaminant releases to the main streams in WAG 2 and to quantify their input to the total contaminant release from the watershed at White Oak Dam (WOD). Efforts focused on {sup 90}Sr, {sup 3}H, and {sup 137}Cs because these contaminants pose the greatest potential human health risk from water ingestion at WOD. Bimonthly sampling was conducted throughout the WOC watershed beginning in March 1993 and ending in August 1994. Samples were also collected for metals, anions, alkalinity, organics, and other radionuclides.

  14. Effects of three diamides (chlorantraniliprole, cyantraniliprole and flubendiamide) on life history, embryonic development and oxidative stress biomarkers of Daphnia magna.

    Science.gov (United States)

    Cui, Feng; Chai, Tingting; Qian, Le; Wang, Chengju

    2017-02-01

    The diamides have become one of the most promising new classes of insecticides. In this study, we evaluated the toxicity of three diamides (chlorantraniliprole, cyantraniliprole and flubendiamide) to Daphnia magna. The acute toxicity test showed that the 48-h EC50 of chlorantraniliprole, cyantraniliprole and flubendiamide were 8.5, 23.9 and 63.5 μg/L, respectively. Biochemical measurements revealed a significant increase in reactive oxygen species (ROS) in D. magna after acute exposure to the three diamides. A significant decrease in activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) was observed, which was consistent with the down-regulated transcription of antioxidant genes sod and gpx. Catalase (CAT) activity exhibited a significant increase while the related gene cat showed no obvious change in daphnids acutely exposed to the three diamides. The chronic test revealed that the three diamides could cause lethal and sub-lethal effects on daphnids within constricted range of concentrations at μg/L level. The 21-d EC50 of chlorantraniliprole, cyantraniliprole and flubendiamide for mobility were 5.0, 13.6 and 36.8 μg/L, respectively. The chronic LOEC of chlorantraniliprole, cyantraniliprole and flubendiamide based on survival, growth and reproduction of D. magna were 4.05, 10.24 and 19.36 μg/L, respectively. Moreover, these three diamides can induce severe developmental abnormalities in D. magna embryos including underdeveloped second antennae, curved tail spine and abnormal body region after acute exposure and the 48-h EC50 were 6.2, 14.1 and 30.8 μg/L for chlorantraniliprole, cyantraniliprole and flubendiamide respectively. Our findings indicate that even low levels of diamides can pose ecological risks to aquatic ecosystems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Methyl farnesoate synthesis is necessary for the environmental sex determination in the water flea Daphnia pulex.

    Science.gov (United States)

    Toyota, Kenji; Miyakawa, Hitoshi; Hiruta, Chizue; Furuta, Kenjiro; Ogino, Yukiko; Shinoda, Tetsuro; Tatarazako, Norihisa; Miyagawa, Shinichi; Shaw, Joseph R; Iguchi, Taisen

    2015-09-01

    Sex-determination systems can be divided into two groups: genotypic sex determination (GSD) and environmental sex determination (ESD). ESD is an adaptive life-history strategy that allows control of sex in response to environmental cues in order to optimize fitness. However, the molecular basis of ESD remains largely unknown. The micro crustacean Daphnia pulex exhibits ESD in response to various external stimuli. Although methyl farnesoate (MF: putative juvenile hormone, JH, in daphnids) has been reported to induce male production in daphnids, the role of MF as a sex-determining factor remains elusive due to the lack of a suitable model system for its study. Here, we establish such a system for ESD studies in D. pulex. The WTN6 strain switches from producing females to producing males in response to the shortened day condition, while the MFP strain only produces females, irrespective of day-length. To clarify whether MF has a novel physiological role as a sex-determining factor in D. pulex, we demonstrate that a MF/JH biosynthesis inhibitor suppressed male production in WTN6 strain reared under the male-inducible condition, shortened day-length. Moreover, we show that juvenile hormone acid O-methyltransferase (JHAMT), a critical enzyme of MF/JH biosynthesis, displays MF-generating activity by catalyzing farnesoic acid. Expression of the JHAMT gene increased significantly just before the MF-sensitive period for male production in the WTN6 strain, but not in the MFP strain, when maintained under male-inducible conditions. These results suggest that MF synthesis regulated by JHAMT is necessary for male offspring production in D. pulex. Our findings provide novel insights into the genetic underpinnings of ESD and they begin to shed light on the physiological function of MF as a male-fate determiner in D. pulex. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Increasing toxicity of enrofloxacin over four generations of Daphnia magna.

    Science.gov (United States)

    Dalla Bona, Mirco; Lizzi, Francesca; Borgato, Arianna; De Liguoro, Marco

    2016-10-01

    The effects of both continuous and alternate exposure to 2mgL(-1) of enrofloxacin (EFX) on survival, growth and reproduction were evaluated over four generations of Daphnia magna. Mortality increased, reaching 100% in most groups by the end of the third generation. Growth inhibition was detected in only one group of the fourth generation. Reproduction inhibition was >50% in all groups and, in second and third generations, groups transferred to pure medium showed a greater inhibition of reproduction than those exposed to EFX. To verify whether the effects observed in these groups could be explained by the perinatal exposure to the antibacterial, a reproduction test with daphnids obtained from in vitro exposed D. magna embryos was also carried out. Perinatal exposure to EFX seemed to act as an 'all-or-nothing' toxicity effect as 31.4% of embryos died, but the surviving daphnids did not show any inhibition of reproduction activity. However, the embryonic mortality may at least partially justify the inhibition of reproduction observed in exposed groups along the multigenerational test. Concluding, the multigenerational test with D. magna did show disruption to a population that cannot be evidenced by the official tests. The increasing deterioration across generations might be inferred as the consequence of heritable alterations. Whilst the concentration tested was higher than those usually detected in the natural environment, the increasing toxicity of EFX across generations and the possible additive toxicity of fluoroquinolone mixtures, prevent harm to crustacean populations by effects in the real context from being completely ruled out. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. A whole sample toxicity assessment to evaluate the sub-lethal toxicity of water and sediment elutriates from a lake exposed to diffuse pollution.

    Science.gov (United States)

    Abrantes, N; Pereira, R; de Figueiredo, D R; Marques, C R; Pereira, M J; Gonçalves, F

    2009-06-01

    The impact of diffuse pollution in aquatic systems is of great concern due to the difficult to measure and regulate it. As part of an ecological risk assessment (ERA), this study aims to use a whole sample toxicity assessment to evaluate the toxicity of water and sediment from Lake Vela, a lake that has been exposed to diffuse pollution. In this way, standard (algae: Pseudokirchneriella subcapitata; cladoceran: Daphnia magna) and local species (algae: Aphanizomenon flos-aquae; cladoceran: Daphnia longispina) were exposed to surface water, and sediment elutriates were collected seasonally from two sites at Lake Vela: one near the east bank (ES), surrounded by agricultural lands; and the other near the west bank (WS), surrounded by a forest. The results confirmed the seasonal contamination of both environmental compartments by pesticides, including organochlorine pesticides, and the presence of high concentrations of nutrients. Although both sites were contaminated, higher levels of pesticides and nutrients were detected in ES, particularly in the sediments. Bioassays showed that water samples (100% concentration) collected in summer and autumn significantly affected the growth rate of P. subcapitata, which could be attributed to the presence of pesticides. Likewise, they revealed an apparent toxicity of elutriates for P. subcapitata and for both daphnids, in summer and autumn. In fact, although pesticides were not detected in elutriates, high levels of un-ionized ammonia were recorded, which is considered highly toxic to aquatic life. By comparing the several species, P. subcapitata was revealed to be the most sensitive one, followed by the daphnids, and then by A. flos-aquae. Results obtained in this study underlined the importance of whole samples toxicity assessment for characterizing the ecological effects of complex mixtures from diffuse inputs, in the ERA processes.

  18. Toxic effects of chemical dispersant Corexit 9500 on water flea Daphnia magna.

    Science.gov (United States)

    Toyota, Kenji; McNabb, Nicole A; Spyropoulos, Demetri D; Iguchi, Taisen; Kohno, Satomi

    2017-02-01

    In 2010, approximately 2.1 million gallons of chemical dispersants, mainly Corexit 9500, were applied in the Gulf of Mexico to prevent the oil slick from reaching shorelines and to accelerate biodegradation of oil during the Deepwater Horizon oil spill. Recent studies have revealed toxic effects of Corexit 9500 on marine microzooplankton that play important roles in food chains in marine ecosystems. However, there is still little known about the toxic effects of Corexit 9500 on freshwater zooplankton, even though oil spills do occur in freshwater and chemical dispersants may be used in response to these spills. The cladoceran crustacean, water flea Daphnia magna, is a well-established model species for various toxicological tests, including detection of juvenile hormone-like activity in test compounds. In this study, we conducted laboratory experiments to investigate the acute and chronic toxicity of Corexit 9500 using D. magna. The acute toxicity test was conducted according to OECD TG202 and the 48 h EC50 was 1.31 ppm (CIs 0.99-1.64 ppm). The reproductive chronic toxicity test was performed following OECD TG211 ANNEX 7 and 21 days LOEC and NOEC values were 4.0 and 2.0 ppm, respectively. These results indicate that Corexit 9500 has toxic effects on daphnids, particularly during the neonatal developmental stage, which is consistent with marine zooplankton results, whereas juvenile hormone-like activity was not identified. Therefore, our findings of the adverse effects of Corexit 9500 on daphnids suggest that application of this type of chemical dispersant may have catastrophic impacts on freshwater ecosystems by disrupting the key food chain network. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  19. A transgenerational endocrine signaling pathway in Crustacea.

    Directory of Open Access Journals (Sweden)

    Gerald A LeBlanc

    Full Text Available BACKGROUND: Environmental signals to maternal organisms can result in developmental alterations in progeny. One such example is environmental sex determination in Branchiopod crustaceans. We previously demonstrated that the hormone methyl farnesoate could orchestrate environmental sex determination in the early embryo to the male phenotype. Presently, we identify a transcription factor that is activated by methyl farnesoate and explore the extent and significance of this transgenerational signaling pathway. METHODOLOGY/PRINCIPAL FINDINGS: Several candidate transcription factors were cloned from the water flea Daphnia pulex and evaluated for activation by methyl farnesoate. One of the factors evaluated, the complex of two bHLH-PAS proteins, dappuMet and SRC, activated a reporter gene in response to methyl farnesoate. Several juvenoid compounds were definitively evaluated for their ability to activate this receptor complex (methyl farnesoate receptor, MfR in vitro and stimulate male sex determination in vivo. Potency to activate the MfR correlated to potency to stimulate male sex determination of offspring (pyriproxyfen>methyl farnesoate>methoprene, kinoprene. Daphnids were exposed to concentrations of pyriproxyfen and physiologic responses determined over multiple generations. Survivial, growth, and sex of maternal organisms were not affected by pyriproxyfen exposure. Sex ratio among offspring (generation 2 were increasingly skewed in favor of males with increasing pyriproxyfen concentration; while, the number of offspring per brood was progressively reduced. Female generation 2 daphnids were reared to reproductive maturity in the absence of pyriproxyfen. Sex ratios of offspring (generation 3 were not affected in this pyriproxyfen lineage, however, the number of offspring per brood, again, was significantly reduced. CONCLUSIONS: Results reveal likely components to a hormone/receptor signaling pathway in a crustacean that orchestrates

  20. Uptake visualization of deltamethrin by NanoSIMS and acute toxicity to the water flea Daphnia magna.

    Science.gov (United States)

    Eybe, T; Bohn, T; Audinot, J N; Udelhoven, T; Cauchie, H M; Migeon, H N; Hoffmann, L

    2009-06-01

    The objective of this study was to investigate the uptake of deltamethrin, an insecticide, by Daphnia magna neonates by SIMS and to compare these findings with results based on established toxicity tests. Young daphnids (aged <24 h) were exposed to 0, 50 and 200 microg L(-1) (ppb) deltamethrin. Mobile, immobile and dead animals were enumerated after 24 and 48 h following OECD 202 [OECD 202, 2004. Daphnia sp., acute immobilisation test, guideline for testing of chemicals] guidelines. The animals were embedded in epoxy resin, cut into semi-thin sections (500 nm) and placed on silicon supporters. NanoSIMS 50 (Cameca) images were made from tissues of the intestine for carbon, nitrogen (measured as CN), phosphorus and bromine. To distinguish between relative concentrations of bromine in the guts from different exposure concentrations of deltamethrin, a carbon normalization method was carried out. Both deltamethrin concentrations and time showed a significant effect on immobilization and mortality of the daphnids (P<0.0001). Bromine from deltamethrin could be visualized by NanoSIMS in all exposed gut tissues (gut wall, microvilli layer, perithropic membrane). Highest deltamethrin concentrations following (12)C normalization were found in animals exposed to 200 microg L(-1) deltamethrin, followed by 50 microg L(-1) and the control. NanoSIMS 50 was successfully used as a supplemental technique for elucidating the relation between the uptake and localization of deltamethrin and its toxicity to D. magna. These results highlight the potential usefulness of NanoSIMS to detect marker elements of xenobiotic compounds within exposed organisms, to compare relative exposure concentrations, and to locate these compounds at their original tissue location.

  1. Comparative ovarian microarray analysis of juvenile hormone-responsive genes in water flea Daphnia magna: potential targets for toxicity.

    Science.gov (United States)

    Toyota, Kenji; Williams, Timothy D; Sato, Tomomi; Tatarazako, Norihisa; Iguchi, Taisen

    2017-03-01

    The freshwater zooplankton Daphnia magna has been extensively employed in chemical toxicity tests such as OECD Test Guidelines 202 and 211. Previously, it has been demonstrated that the treatment of juvenile hormones (JHs) or their analogues to female daphnids can induce male offspring production. Based on this finding, a rapid screening method for detection of chemicals with JH-activity was recently developed using adult D. magna. This screening system determines whether a chemical has JH-activity by investigating the male offspring inducibility. Although this is an efficient high-throughput short-term screening system, much remains to be discovered about JH-responsive pathways in the ovary, and whether different JH-activators act via the same mechanism. JH-responsive genes in the ovary including developing oocytes are still largely undescribed. Here, we conducted comparative microarray analyses using ovaries from Daphnia magna treated with fenoxycarb (Fx; artificial JH agonist) or methyl farnesoate (MF; a putative innate JH in daphnids) to elucidate responses to JH agonists in the ovary, including developing oocytes, at a JH-sensitive period for male sex determination. We demonstrate that induction of hemoglobin genes is a well-conserved response to JH even in the ovary, and a potential adverse effect of JH agonist is suppression of vitellogenin gene expression, that might cause reduction of offspring number. This is the first report demonstrating different transcriptomics profiles from MF and an artificial JH agonist in D. magna ovary, improving understanding the tissue-specific mode-of-action of JH. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Reduced cadmium accumulation and toxicity in Daphnia magna under carbon nanotube exposure.

    Science.gov (United States)

    Liu, Jie; Wang, Wen-Xiong

    2015-12-01

    With increasing application and commercial production, carbon nanotubes (CNTs) will inevitably be released into aquatic environments and affect the transport and toxicity of toxic metals in ecosystems. The present study examined how CNTs affected the biokinetics and toxicity of a toxic metal, cadmium (Cd), in the freshwater zooplankton Daphnia magna. The authors quantified the dissolved uptake and the 50% lethal concentration (LC50, 48 h and 72 h) of Cd in daphnids in the presence of functionalized multiwalled nanotubes (F-CNTs) with different lengths (10-30 µm vs 0.5-2 µm) and concentrations (4 mg/L and 8 mg/L). Compared with the control treatment without CNTs, both CNTs slowed down the accumulation rate of Cd in D. magna over 8 h of exposure and further reduced the accumulation thereafter. Mechanisms for the reduced Cd uptake were mainly related to the influences of CNTs on the physiological activity of daphnids. The LC50 of D. magna in the presence of Cd and shorter CNTs was almost the same as that of the control group without CNTs. However, the LC50 of the groups with normal CNTs was significantly higher than that of the control group (i.e., F-CNTs decreased Cd toxicity significantly). Meanwhile, CNTs also decreased the tolerance of D. magna to Cd. The present study suggests that different physical properties of CNTs, such as length, need to be considered in the environmental risk assessment of CNTs.

  3. Effects of dietary exposure to herbicide and of the nutritive quality of contaminated food on the reproductive output of Daphnia magna.

    Science.gov (United States)

    Bessa da Silva, M; Abrantes, N; Rocha-Santos, T A P; Duarte, A C; Freitas, A C; Gomes, A M; Carvalho, A P; Marques, J C; Gonçalves, F; Pereira, R

    2016-10-01

    Risk assessment of pesticides has been based on direct toxic effects on aquatic organisms. Indirect effects data are taken into account but with limitations, as it is frequently difficult to predict their real impacts in the ecosystems. In this context the main aim of this work was to assess how the exposure to the herbicide pendimethalin (Prowl(®)), under environmentally relevant concentrations, may compromise the nutritional composition of food for a relevant group of primary consumers of freshwater food webs-the daphnids, thus affecting their reproduction performance and subsequently the long-term sustainability of active populations of this grazer. Therefore, Daphnia magna individuals were chronically exposed in a clean medium to a control diet (NCF - i.e., non-contaminated green algae Raphidocelis subcapitata) and to a contaminated diet (CF - i.e., the same monoalgal culture grown in a medium enriched with pendimethalin in a concentration equivalent to the EC20 for growth inhibition of algae), during which reproductive endpoints were assessed. The algae were analysed for protein, carbohydrate and fatty acid content. The chemical composition of R. subcapitata in the CF revealed a slight decrease on total fatty acid levels, with a particular decrease of essential ω9 monounsaturated fatty acids. In contrast, the protein content was high in the CF. D. magna exposed to CF experienced a 16% reduction in reproduction, measured as the total number of offspring produced per female. Additionally, an internal pendimethalin body burden of 4.226μgg(-1) was accumulated by daphnids fed with CF. Hence, although it is difficult to discriminate the contribution of the pesticide (as a toxic agent transferred through the food web) from that of the food with a poor quality-compromised by the same pesticide, there are no doubts that, under environmentally relevant concentrations of pesticides, both pathways may compromise the populations of freshwater grazers in the long term

  4. Environmental impact of industrial sludge stabilization/solidification products: chemical or ecotoxicological hazard evaluation?

    Science.gov (United States)

    Silva, Marcos A R; Testolin, Renan C; Godinho-Castro, Alcione P; Corrêa, Albertina X R; Radetski, Claudemir M

    2011-09-15

    Nowadays, the classification of industrial solid wastes is not based on risk analysis, thus the aim of this study was to compare the toxicity classifications based on the chemical and ecotoxicological characterization of four industrial sludges submitted to a two-step stabilization/solidification (S/S) processes. To classify S/S products as hazardous or non-hazardous, values cited in Brazilian chemical waste regulations were adopted and compared to the results obtained with a battery of biotests (bacteria, alga and daphnids) which were carried out with soluble and leaching fractions. In some cases the hazardous potential of industrial sludge was underestimated, since the S/S products obtained from the metal-mechanics and automotive sludges were chemically classified as non-hazardous (but non-inert) when the ecotoxicity tests showed toxicity values for leaching and soluble fractions. In other cases, the environmental impact was overestimated, since the S/S products of the textile sludges were chemically classified as non-inert (but non-hazardous) while ecotoxicity tests did not reveal any effects on bacteria, daphnids and algae. From the results of the chemical and ecotoxicological analyses we concluded that: (i) current regulations related to solid waste classification based on leachability and solubility tests do not ensure reliable results with respect to environmental protection; (ii) the two-step process was very effective in terms of metal immobilization, even at higher metal-concentrations. Considering that S/S products will be subject to environmental conditions, it is of great interest to test the ecotoxicity potential of the contaminants release from these products with a view to avoiding environmental impact given the unreliability of ecotoxicological estimations originating from chemical analysis. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Longevity of Daphnia and the attenuation of stress responses by melatonin.

    Science.gov (United States)

    Schwarzenberger, Anke; Christjani, Mark; Wacker, Alexander

    2014-11-06

    The widespread occurrence of melatonin in prokaryotes as well as eukaryotes indicates that this indoleamine is considerably old. This high evolutionary age has led to the development of diverse functions of melatonin in different organisms, such as the detoxification of reactive oxygen species and anti-stress effects. In insects, i.e. Drosophila, the addition of melatonin has also been shown to increase the life span of this arthropod, probably by reducing age-related increasing oxidative stress. Although the presence of melatonin was recently found to exist in the ecological and toxicological model organism Daphnia, its function in this cladoceran has thus far not been addressed. Therefore, we challenged Daphnia with three different stressors in order to investigate potential stress-response attenuating effects of melatonin. i) Female and male daphnids were exposed to melatonin in a longevity experiment, ii) Daphnia were confronted with stress signals from the invertebrate predator Chaoborus sp., and iii) Daphnia were grown in high densities, i.e. under crowding-stress conditions. In our experiments we were able to show that longevity of daphnids was not affected by melatonin. Therefore, age-related increasing oxidative stress was probably not compensated by added melatonin. However, melatonin significantly attenuated Daphnia's response to acute predator stress, i.e. the formation of neckteeth which decrease the ability of the gape-limited predator Chaoborus sp. to handle their prey. In addition, melatonin decreased the extent of crowding-related production of resting eggs of Daphnia. Our results confirm the effect of melatonin on inhibition of stress-signal responses of Daphnia. Until now, only a single study demonstrated melatonin effects on behavioral responses due to vertebrate kairomones, whereas we clearly show a more general effect of melatonin: i) on morphological predator defense induced by an invertebrate kairomone and ii) on life history characteristics

  6. Physiological interaction of Daphnia and Microcystis with regard to cyanobacterial secondary metabolites.

    Science.gov (United States)

    Sadler, Thomas; von Elert, Eric

    2014-11-01

    Cyanobacterial blooms in freshwater ecosystems are a matter of high concern with respect to human health and ecosystem services. Investigations on the role of cyanobacterial secondary metabolites have largely been confined to microcystins, although cyanobacteria produce a huge variety of toxic or inhibitory secondary metabolites. Mass occurrences of toxic cyanobacteria strongly impact freshwater zooplankton communities; especially the unselective filter feeder Daphnia. Daphnids have been shown to successfully suppress bloom formation. However, the opposite situation, i.e. the suppression of Daphnia populations by cyanobacteria can be observed as well. To understand these contradictory findings the elucidation of the underlying physiological mechanisms that help daphnids to cope with cyanotoxins is crucial. We fed Daphnia magna with the cyanobacterium Microcystis aeruginosa PCC7806 for 24h and used high-resolution LCMS analytics to analyze the Microcystis cells, the Daphnia tissue and the surrounding medium in order to investigate the fate of seven investigated cyanobacterial compounds (cyanopeptolins A-C, microcyclamide 7806A and aerucyclamides B-D). For none of these bioactive compounds evidence for biotransformation or biodegradation by Daphnia were found. Instead feeding and subsequent release experiments point at the importance of transport mechanisms in Daphnia with regard to the cyanopeptolins A and C and microcyclamide 7806A. In addition we found hints for new inducible defense mechanism in Microcystis against predation by Daphnia. These putative defense mechanisms include the elevated production of toxic compounds other than microcystins, as could be demonstrated here for aerucyclamide B and D, cyanopoeptolin B and microcyclamide 7806A. Moreover, our data demonstrate the elevated active export of at least one cyanobacterial compound (microcyclamide 7806A) into the surrounding medium as a response to grazer presence, which might constitute an entirely new

  7. Accumulation and inactivation of avian influenza virus by the filter-feeding invertebrate Daphnia magna.

    Science.gov (United States)

    Meixell, Brandt W; Borchardt, Mark A; Spencer, Susan K

    2013-12-01

    The principal mode of avian influenza A virus (AIV) transmission among wild birds is thought to occur via an indirect fecal-oral route, whereby individuals are exposed to virus from the environment through contact with virus-contaminated water. AIV can remain viable for an extended time in water; however, little is known regarding the influence of the biotic community (i.e., aquatic invertebrates) on virus persistence and infectivity in aquatic environments. We conducted laboratory experiments to investigate the ability of an aquatic filter-feeding invertebrate, Daphnia magna, to accumulate virus from AIV-dosed water under the hypothesis that they represent a potential vector of AIV to waterfowl hosts. We placed live daphnids in test tubes dosed with low-pathogenicity AIV (H3N8 subtype isolated from a wild duck) and sampled Daphnia tissue and the surrounding water using reverse transcription-quantitative PCR (RT-qPCR) at 3- to 120-min intervals for up to 960 min following dosing. Concentrations of viral RNA averaged 3 times higher in Daphnia tissue than the surrounding water shortly after viral exposure, but concentrations decreased exponentially through time for both. Extracts from Daphnia tissue were negative for AIV by cell culture, whereas AIV remained viable in water without Daphnia present. Our results suggest daphnids can accumulate AIV RNA and effectively remove virus particles from water. Although concentrations of viral RNA were consistently higher in Daphnia tissue than the water, additional research is needed on the time scale of AIV inactivation after Daphnia ingestion to fully elucidate Daphnia's role as a potential vector of AIV infection to aquatic birds.

  8. Ecotoxicological effects of larvicide used in the control of Aedes aegypti on nontarget organisms: Redefining the use of pyriproxyfen.

    Science.gov (United States)

    Santos, Vanessa Santana Vieira; Caixeta, Evelyn Siqueira; Olegário de Campos Júnior, Edimar; Pereira, Boscolli Barbosa

    2017-01-17

    The continued widespread use of larvicides in Aedes aegypti control programs is still a necessary strategy, since there are no apparent efficient vaccines against arboviruses. However, chemical approaches may affect nontarget organisms and produce detrimental effects to environmental health. Therefore, the aim of this study was to conduct toxicity testing for pyriproxyfen at different concentrations using Daphnia magna and Artemia salina as model organisms to evaluate the ecotoxicological parameters. This study describes the toxicological effects of pyriproxyfen on both microcrustaceans, which are widely used in bioassays because of their sensitivity to changes in hydrosphere. Data demonstrated that the calculated EC50-48h value of pyriproxyfen was 2.5 μg/for D. magna and A. salina; the no-observed-effect concentration (NOEC) and the lowest-observed-effect concentration (LOEC) of pyriproxyfen were found to be 0.63 and 1.25 μg/L for Artemia salina and Daphnia magna, respectively. In chronic toxicity and reproduction tests on D. magna, a calculated CL50-7day (lethality on 50% of daphnids after 7 days of chronic test) and an EC50-21day (50% reduction in the reproductive output of parental daphnids after 21 days of exposure) higher than 1.25 μg/L pyriproxyfen were observed. The time of first reproduction was significantly increased in D. magna after exposure to environmentally relevant concentrations of pyriproxyfen, but other reproduction parameters were not markedly altered. Environmental risk assessment revealed that pyriproxyfen is highly toxic for both branchiopods. Data demonstrated that pyriproxyfen may produce adverse effects on the aquatic ecosystem at concentrations required to control Ae. aegypti.

  9. Potential impact of low-concentration silver nanoparticles on predator-prey interactions between predatory dragonfly nymphs and Daphnia magna as a prey.

    Science.gov (United States)

    Pokhrel, Lok R; Dubey, Brajesh

    2012-07-17

    This study investigated the potential impacts of low-concentration citrate-coated silver nanoparticles (citrate-nAg; 2 μg L(-1) as total Ag) on the interactions of Daphnia magna Straus (as a prey) with the predatory dragonfly ( Anax junius : Odonata) nymph using the behavioral, survival, and reproductive end points. Four different toxicity bioassays were evaluated: (i) horizontal migration; (ii) vertical migration; (iii) 48 h survival; and (iv) 21 day reproduction; using four different treatment combinations: (i) Daphnia + citrate-nAg; (ii) Daphnia + predator; (iii) Daphnia + citrate-nAg + predator; and (iv) Daphnia only (control). Daphnia avoided the predators using the horizontal and vertical movements, indicating that Daphnia might have perceived a significant risk of predation. However, with citrate-nAg + predator treatment, Daphnia response did not differ from control in the vertical migration test, suggesting that Daphnia were unable to detect the presence of predator with citrate-nAg treatment and this may have potential implication on daphnids population structure owing to predation risk. The 48 h survival test showed a significant mortality of Daphnia individuals in the presence of predators, with or without citrate-nAg, in the test environment. Average reproduction of daphnids increased by 185% with low-concentration citrate-nAg treatment alone but was severely compromised in the presence of predators (decreased by 91.3%). Daphnia reproduction was slightly enhanced by approximately 128% with citrate-nAg + predator treatment. Potential mechanisms of these differential effects of low-concentration citrate-nAg, with or without predators, are discussed. Because silver dissolution was minimal, the observed toxicity could not be explained by dissolved Ag alone. These findings offer novel insights into how exposure to low-concentration silver nanoparticles could influence predator-prey interactions in the fresh water systems.

  10. n vivo retention of ingested Au NPs by Daphnia magna: No evidence for trans-epithelial alimentary uptake

    Science.gov (United States)

    Khan, Farhan R.; Kennaway, Gabrielle M.; Croteau, Marie-Noële; Dybowska, Agnieszka; Smith, Brian D.; Nogueira, António J.A.; Rainbow, Philip S.; Luoma, Samuel N.; Valsami-Jones, Eugenia

    2014-01-01

    In vivo studies with Daphnia magna remain inconclusive as to whether engineered nanoparticles (NPs) are internalized into tissues after ingestion. Here we used a three-pronged approach to study the in vivo retention and efflux kinetics of 20 nm citrate stabilized Au NPs ingested by this key aquatic species. Daphnids were exposed to suspended particles (600 μg L−1) for 5 h after which they were depurated for 24 h in clean water containing algae. Light microscopy was used to follow the passage of Au NPs through the gastrointestinal tract, Au body burdens were determined by ICP-MS (inductively coupled plasma mass spectrometry), and transmission electron microscopy (TEM) was used to examine the presence and distribution of Au NPs in tissues. Results revealed that the elimination of Au NPs was bi-phasic. The fast elimination phase lasted −1 (±SE) which accounted for ∼75% of the ingested Au. The remaining ∼25% of the ingested Au NPs was eliminated at a 100-fold slower rate. TEM analysis revealed that Au NPs in the midgut were in close proximity to the peritrophic membrane after 1 and 24 h of depuration. There were no observations of Au NP uptake at the microvilli. Thus, although Au NPs were retained in the gut lumen, there was no observable internalization into the gut epithelial cells. Similar to carbon nanotubes and CuO NPs, our findings indicate that in daphnids the in vivo retention of Au NPs does not necessarily result in their internalization.

  11. Effects of charge and surface ligand properties of nanoparticles on oxidative stress and gene expression within the gut of Daphnia magna

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez, Gustavo A.; Lohse, Samuel E.; Torelli, Marco; Murphy, Catherine; Hamers, Robert J.; Orr, Galya; Klaper, Rebecca D.

    2015-05-01

    Concern has been raised regarding the current and future release of engineered nanomaterials into aquatic environments from industry and other sources. However, not all nanomaterials may cause an environ-mental impact and identifying which nanomaterials may be of greatest concern has been difficult. It is thought that the surface groups of a functionalized nanoparticles (NPs) may play a significant role in determining their interactions with aquatic organisms, but the way in which surface properties of NPs impact their toxicity in whole organisms has been minimally explored. A major point of interaction of NPs with aquatic organisms is in the gastrointestinal tract as they ingest particulates from the water column or from the sediment. The main goal of this study was to use model gold NP (AuNPs) to evaluate the potential effects of the different surfaces groups on NPs on the gut of an aquatic model organism, Daphnia magna. In this study, we exposed daphnids to a range of AuNPs concentrations and assessed the impact of AuNP exposure in the daphnid gut by measuring reactive oxygen species (ROS) production and expression of genes associated with oxidative stress and general cellular stress: glutathione S-transferase(gst), catalase (cat), heat shock protein 70 (hsp70), and metallothionein1 (mt1). We found ROS formation and gene expression were impacted by both charge and the specific surface ligand used. We detected some degree of ROS production in all NP exposures, but positively charged AuNPs induced a greater ROS response. Similarly, we observed that, compared to controls, both positively charged AuNPs and only one negatively AuNP impacted expression of genes associated with cellular stress. Finally, ligand-AuNP exposures showed a different toxicity and gene expression profile than the ligand alone, indicating a NP specific effect.

  12. Chronic toxicity of azoxystrobin to freshwater amphipods, midges, cladocerans, and mussels in water-only exposures

    Science.gov (United States)

    Kunz, James L.; Ingersoll, Christopher G.; Smalling, Kelly; Elskus, Adria; Kuivila, Kathryn

    2017-01-01

    Understanding the effects of fungicides on nontarget organisms at realistic concentrations and exposure durations is vital for determining potential impacts on aquatic ecosystems. Environmental concentrations of the fungicide azoxystrobin have been reported up to 4.6 μg/L in the United States and 30 μg/L in Europe. The objective of the present study was to evaluate the chronic toxicity of azoxystrobin in water-only exposures with an amphipod (Hyalella azteca; 42-d exposure), a midge (Chironomus dilutus; 50-d exposure), a cladoceran (Ceriodaphnia dubia; 7-d exposure), and a unionid mussel (Lampsilis siliquoidea; 28-d exposure) at environmentally relevant concentrations. The potential photo-enhanced toxicity of azoxystrobin accumulated by C. dubiaand L. siliquoidea following chronic exposures to azoxystrobin was also evaluated. The 20% effect concentrations (EC20s) based on the most sensitive endpoint were 4.2 μg/L for H. aztecareproduction, 12 μg/L for C. dubia reproduction and C. dilutus emergence, and >28 μg/L for L. siliquoidea. Hyalella azteca was more sensitive to azoxystrobin compared with the other 3 species in the chronic exposures. No photo-enhanced toxicity was observed for either C. dubia or L. siliquoidea exposed to ultraviolet light in control water following azoxystrobin tests. The results of the present study indicate chronic effects of azoxystrobin on 3 of 4 invertebrates tested at environmentally relevant concentrations. The changes noted in biomass and reproduction have the potential to alter the rate of ecological processes driven by aquatic invertebrates. Environ Toxicol Chem 2017;9999:1–8. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

  13. Ecotoxicological assessment of sediments from Tiete river between Salesopolis and Suzano, SP (Brazil); Avaliacao ecotoxicologica de sedimentos do rio Tiete, entre os municipios de Salesopolis e Suzano, SP

    Energy Technology Data Exchange (ETDEWEB)

    Alegre, Gabriel Fonseca

    2009-07-01

    Once introduced into the aquatic environment, many substances can bind or be adsorbed by organic particles in suspension. Depending on the river morphology and hydrological conditions, these particles in suspension containing the contaminants can be deposited along its course, becoming part of the bottom sediments, making them actual sinks and often a source of contamination for the water column and benthic organisms. In the assessment of water, sediment has been one of the most important indicators of the contamination levels in aquatic ecosystems, representing the deposition of contaminants in the environment that occurred over the years and even decades. The Tiete River cross the Sao Paulo state, however, in the metropolitan region of Sao Paulo, the river shows the most severe degradation. In the region of Salesopolis, the waters of the Tiete River are used for public supply, but across the city of Mogi das Cruzes the water quality decreases significantly. Considering the importance of the Tiete river and the sediment for the aquatic biota, this study aimed to evaluate the toxicity of the sediment at five points along the Tiete river, between the cities of Salesopolis and Suzano, Sao Paulo. Four sampling were carried out: two in the summer (rainy season) and two in winter (dry season). The whole sediment was assessed by acute and chronic toxicity tests with Hyalella azteca and Ceriodaphnia dubia, respectively, the elutriate was assessed by chronic toxicity test using C. dubia, while the porewater was evaluated by acute toxicity test with Vibrio fischeri. Samples of river water were also evaluated for chronic toxicity tests with C. dubia. The quantification of metals and hydrocarbons in sediment samples was also carried out in order to correlate the biological effects with the chemical contamination. The obtained results with the whole sediment test indicate Mogi das Cruzes and Suzano cities as the most toxic sites and also as the sites with the highest

  14. [Feeding habits and trophic ecology of the fish Lutjanus griseus (Pisces: Lutjanidae) associated with submerged vegetation in Laguna de Términos, Campeche, Mexico].

    Science.gov (United States)

    Guevara, Emma; Alvarez, Hernán; Mascaró, Maite; Rosas, Carlos; Sánchez, Alberto

    2007-01-01

    In Campeche, Mexico, the Laguna de Términos has Thalassia testudinum beds inhabited by the grey snapper, Lutjanus griseus (Linnaeus 1758). Along one year, we collected 994 individuals and 672 had food in their stomachs; we recorded number, weight, and frequency oftrophic groups, and the index of relative importance. Dominant food components were Farfantepenaeus duorarum and Palemonetes octaviae, Eucinostomus gula (Cuvier 1830) and Libinia dubia. Salinity and temperature were related to the number of individuals collected and with greater fish consumption by large L. griseus. The trophic niche breadth index was calculated for six size-classes of fish. The smallest and the largest fish had the lowest index values, whereas medium-size snappers had higher values. This snapper has a preference for habitats with submerged vegetation. The percentage of fish with food in their stomachs was higher during dark hours, providing evidence of the nocturnal habits of this fish.

  15. The Dilaridae of the Balkan Peninsula and of Anatolia (Insecta, Neuropterida, Neuroptera

    Directory of Open Access Journals (Sweden)

    Ulrike Aspöck

    2015-07-01

    Full Text Available Basing upon all available information on type material of Dilar turcicus Hagen, 1858, Dilar syriacus Navás, 1909, and Dilar lineolatus Navás, 1909, together with a large number of dilarid specimens, the pleasing lacewings of Anatolia and Southeast Europe are revised. The current taxonomic concept of D. turcicus is confirmed, and a lectotype is designated. Dilar turcicus is widely distributed in the southeast of Europe (being the only representative of Dilaridae in this region, in Anatolia, and, most probably, in the Caucasus region. Dilar syriacus and D. lineolatus remain nomina dubia. Dilar syriacus might occur in Anatolia, while D. lineolatus is a species occurring in western Central Asia. Two new species, Dilar anatolicus sp. n. and Dilar fuscus sp. n. are described from Anatolia. Wings and genital segments of the three species occurring in Anatolia are illustrated, and a map documenting the known distribution of these species is provided.

  16. 上海植物区系新资料(Ⅵ)%Newly recorded plants in Shanghai (Ⅵ)

    Institute of Scientific and Technical Information of China (English)

    李宏庆; 熊申展; 陈纪云; 桂萍; 胡超

    2013-01-01

    A newly exotic genus Kickxia Dumort. (Scrophulariaceae) is recorded in Shanghai and China. And 11 newly recorded species are found in Shanghai, namely, Kickxia elatine (L. ) Dumort. , Amaranthus polygonoides L. , Ampelopsis japonica (Thunb. ) Makino, Asarum forbesii Maxim. , Ammannia multiflora Roxb. , Elymus shandongensis B. Salomon, Rorippa dubia (Pers. ) H. Hara, Cardamine scutata Thunb. , Corydalis sheareri S. Moore, Basella alba L. and Melochia corchorifolia L. respectively.%记载了中国及上海新记录外来植物凯氏草属,上海新记录植物戟叶凯氏草、合被苋、白蔹、杜衡、多花水苋菜、山东披碱草、无瓣蔊菜、圆齿碎米荠、地锦苗、落葵及马松子等11种.

  17. Characterization of explosives processing waste decomposition due to composting

    Energy Technology Data Exchange (ETDEWEB)

    Griest, W.H.; Tyndall, R.L.; Stewart, A.J.; Ho, C.H.; Ironside, K.S.; Caton, J.E.; Caldwell, W.M.; Tan, E.

    1991-11-01

    Static pile and mechanically stirred composts generated at the Umatilla Army Depot Activity in a field composting optimization study were chemically and toxicologically characterized to provide data for the evaluation of composting efficiency to decontaminate and detoxify explosives-contaminated soil. Characterization included determination of explosives and 2,4,6,-trinitrotoluene metabolites in composts and their EPA Synthetic Precipitation Leaching Procedure Leachates, leachate toxicity to Ceriodaphnia Dubia and mutagenicity of the leachates and organic solvent extracts of the composts to Ames bacterial strains TA-98 and TA-100. The main conclusion from this study is that composting can effectively reduce the concentrations of explosives and bacterial mutagenicity in explosives -- contaminated soil, and can reduce the aquatic toxicity of leachable compounds. Small levels of explosive and metabolites, bacterial mutagenicity, and leachable aquatic toxicity remain after composting. The ultimate fate of the biotransformed explosives, and the source(s) of residual toxicity and mutagenicity remain unknown.

  18. Characterization of explosives processing waste decomposition due to composting. Phase 2, Final report

    Energy Technology Data Exchange (ETDEWEB)

    Griest, W.H.; Tyndall, R.L.; Stewart, A.J.; Ho, C.H.; Ironside, K.S.; Caton, J.E.; Caldwell, W.M.; Tan, E.

    1991-11-01

    Static pile and mechanically stirred composts generated at the Umatilla Army Depot Activity in a field composting optimization study were chemically and toxicologically characterized to provide data for the evaluation of composting efficiency to decontaminate and detoxify explosives-contaminated soil. Characterization included determination of explosives and 2,4,6,-trinitrotoluene metabolites in composts and their EPA Synthetic Precipitation Leaching Procedure Leachates, leachate toxicity to Ceriodaphnia Dubia and mutagenicity of the leachates and organic solvent extracts of the composts to Ames bacterial strains TA-98 and TA-100. The main conclusion from this study is that composting can effectively reduce the concentrations of explosives and bacterial mutagenicity in explosives -- contaminated soil, and can reduce the aquatic toxicity of leachable compounds. Small levels of explosive and metabolites, bacterial mutagenicity, and leachable aquatic toxicity remain after composting. The ultimate fate of the biotransformed explosives, and the source(s) of residual toxicity and mutagenicity remain unknown.

  19. NEW CONTRIBUTION TO THE STUDY OF ALIEN FLORA IN ROMANIA

    Directory of Open Access Journals (Sweden)

    SÎRBU CULIŢĂ

    2011-12-01

    Full Text Available In this paper, a number of seventeen alien plant species are presented, one of them being now for the first time reported in Romania (Sedum sarmentosum Bunge. Some species are mentioned for the first time in the flora of Moldavia (Aster novae-angliae L., Cenchrus incertus M. A. Curtis, Chenopodium pumilio R. Br., Fraxinus americana L., Lindernia dubia (L. Pennell, Petunia × atkinsiana D. Don, Solidago gigantea Aiton, Tagetes erecta L. or Transylvania (Kochia sieversiana (Pallas C. A. Mey., and some are reported from new localities (seven species. For each species, there are presented general data on the geographical origin, its distribution in Europe and worldwide, as well as its invasion history and current distribution in Romania. Some of these species manifest a remarkable spreading tendency, expanding their invasion area in Romania. Voucher specimens were deposited in the Herbarium of University of Agricultural Sciences and Veterinary Medicine Iaşi (IASI.

  20. Investigating salt and naphthenic acids interactions in the toxicity of oil sands process water to freshwater invertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, D.; Kautzman, M.; Wojnarowicz, P.; Cutter, J.; Bird, E.; Liber, K. [Saskatchewan Univ., Regina, SK (Canada)

    2010-07-01

    The hot water extraction process used to produce bitumens from oil sands produces a large volume of oil sands process water (OSPW) that contain elevated concentrations of naphthenic acids (NA) and salts. Many oil sands reclamation projects are proposing the use of OSPW as part of reconstructed wetlands projects. This study investigated the toxicity of OSPW to freshwater invertebrates. The toxic interactions between NA and salinity on freshwater invertebrates were assessed. Bioassays with laboratory-cultured Ceriodaphnia dubia were conducted to determine the toxicity of OSPW from selected water bodies. The study showed that while the concentrations of NAs and salinity were elevated in OSPW waters that caused toxic responses, the concentrations of salinity ions varied greatly among the OSPW samples. Results of the study suggested that ion composition may be a factor in toxicity. Interactions between NAs and salinity were then assessed by performing bioassays with mixtures representing major ion combinations in OSPW.

  1. PROPAGAÇÃO ASSEXUADA DO CAMU-CAMU (Myrciaria dúbia) ATRAVÉS DE ENXERTIAS DO TIPO GARFAGEM

    OpenAIRE

    Sidney Alberto do Nascimento Ferreira; Daniel Felipe de Oliveira Gentil

    1997-01-01

    O camu-camu (Myrciaria dubia (H.B.K.) McVaugh), espécie nativa da Amazônia, cujos frutos apresentam elevado teor de vitamina C, normalmente é propagado através da semente o que não garante a reprodução de bons caracteres. Esta pesquisa teve por objetivo avaliar a multiplicação do camu-camu por meio de diferentes métodos de enxertias do tipo garfagem, visando a produção de material selecionado na região de Manaus, AM. As enxertias foram realizadas quando as mudas alcançaram um ano de idade com...

  2. Review of Baeolidia, the largest genus of Aeolidiidae (Mollusca: Nudibranchia), with the description of five new species.

    Science.gov (United States)

    Carmona, Leila; Pola, Marta; Gosliner, Terrence M; Cervera, Juan Lucas

    2014-05-28

    This paper discusses the systematics of the aeolid genus Baeolidia Bergh, 1888. To date, this monophyletic genus is the most diverse within Aeolidiidae with sixteen valid species. Excluding Baeolidia cryoporos Bouchet, 1977, the genus is restricted to the Indo-Pacific and Eastern Pacific. Species of Baeolidia show a huge intrageneric variability in several morphological characters. Only oral glands, if present, may distinguish Baeolidia from other aeolidiids genera. Aeolidiella occidentalis Bergh, 1875, Aeolidiella faustina Bergh, 1900 and Spurilla orientalis Bergh, 1905 are transferred to Baeolidia but they are considered nomina dubia. Five new species, Baeolidia rieae sp. nov., Baeolidia variabilis sp. nov., Baeolidia lunaris sp. nov., Baeolidia gracilis sp. nov. and Baeolidia scottjohnsoni sp. nov. are described.

  3. Hardness corrections for copper are inappropriate for protecting sensitive freshwater biota.

    Science.gov (United States)

    Markich, S J; Batley, G E; Stauber, J L; Rogers, N J; Apte, S C; Hyne, R V; Bowles, K C; Wilde, K L; Creighton, N M

    2005-06-01

    Toxicity testing using a freshwater alga (Chlorella sp.), a bacterium (Erwinnia sp.) and a cladoceran (Ceriodaphnia cf. dubia) exposed to copper in synthetic and natural freshwaters of varying hardness (44-375 mg CaCO3/l), with constant alkalinity, pH and dissolved organic carbon concentration, demonstrated negligible hardness effects in the pH range 6.1-7.8. Therefore, the use of a generic hardness-correction algorithm, developed as part of national water quality guidelines for protecting freshwater biota, is not recommended for assessing the toxicity of copper to these, and other, sensitive freshwater species. Use of the algorithm for these sensitive species will be underprotective because the calculated concentrations of copper in water that cause a toxic effect will be higher.

  4. Toxicity of fluoride to aquatic species and evaluation of toxicity modifying factors.

    Science.gov (United States)

    Pearcy, Krysta; Elphick, James; Burnett-Seidel, Charlene

    2015-07-01

    The present study was performed to investigate the toxicity of fluoride to a variety of freshwater aquatic organisms and to establish whether water quality variables contribute substantively to modifying its toxicity. Water hardness, chloride, and alkalinity were tested as possible toxicity modifying factors for fluoride using acute toxicity tests with Hyalella azteca and Oncorhynchus mykiss. Chloride appeared to be the major toxicity modifying factor for fluoride in these acute toxicity tests. The chronic toxicity of fluoride was evaluated with a variety of species, including 3 fish (Pimephales promelas, O. mykiss, and Salvelinus namaycush), 3 invertebrates (Ceriodaphnia dubia, H. azteca, and Chironomus dilutus), 1 plant (Lemna minor), and 1 alga (Pseudokirchneriella subcapitata). Hyalella azteca was the most sensitive species overall, and O. mykiss was the most sensitive species of fish. The role of chloride as a toxicity modifying factor was inconsistent between species in the chronic toxicity tests.

  5. Diversity of Endophytic Fungi Associated with the Roots of Four Aquatic Plants Inhabiting Two Wetlands in Korea.

    Science.gov (United States)

    You, Young-Hyun; Park, Jong Myong; Park, Jong-Han; Kim, Jong-Guk

    2015-09-01

    A total of 4 aquatic plants, Eleocharis kuroguwai Ohwi, Hydrocharis dubia Backer, Salvinia natans All., and Zizania latifolia Turcz., were sampled from representative two wetlands of South Korea. A total of 38 endophytic fungal strains were isolated from aquatic plants native to the Daepyeong wetland, and 27 strains were isolated from the Jilnal wetland. The internal transcribed spacer regions of fungal isolates were sequenced and a phylogenetic analysis was performed. In addition, endophytic fungal diversity from each wetland and host plant species was deduced. A total of 25 fungal genera were purely isolated, and 16 fungal genera were isolated from each of the two wetlands. Commonly isolated genera from both wetlands were Aspergillus, Cladosporium, Clonostachys, Fusarium, Leptosphaeria, Penicillium, and Talaromyces. This study revealed that fungal diversity varied with environmental conditions and by host plant in representative two wetlands.

  6. Ecology of Triatoma rubrovaria (Hemiptera, Triatominae) in wild and peridomestic environments of Uruguay.

    Science.gov (United States)

    Salvatella, R; Rosa, R; Basmadjian, Y; Puime, A; Calegari, L; Guerrero, J; Martinez, M; Mendaro, G; Briano, D; Montero, C

    1995-01-01

    This paper describes population structure, spatial distribution and habitat selection of wild and peridomestic populations of Triatoma rubrovaria (Blanchard, 1843). Field studies were carried out at Las Piedras and La Bolsa in the Northern Department of Artigas, Uruguay. A semicircular sampling area, divided in seven or eight triangular sectors was sequentially examined from October 1990 to November 1991. At Las Piedras (typical wild habitat) 1063 T. rubrovaria bugs were collected from 84% of the rocky outcroops ("pedregales"). Abundance varied by season peaking in October-November (spring). Throughout the year, most of the population was made up of third, fourth and fifth instar nymphs; adults were found from October to March. In the peridomestic environment of La Bolsa, however T. rubrovaria was less common and showed a more irregular instar distribution. Colonized ecotopes, were those close to houses. In both sites T. rubrovaria was mainly associated with the geckonid Homonota uruguayensis and the cockroach Blaptica dubia.

  7. Ecology of Triatoma rubrovaria (Hemiptera, Triatominae in wild and peridomestic environments of Uruguay

    Directory of Open Access Journals (Sweden)

    Roberto Salvatella

    1995-06-01

    Full Text Available This paper describes population structure, spatial distribution and habitat selection of wild and peridomestic populations of Triatoma rubrovaria (Blanchard, 1843. Field studies were carried out at Las Piedras and La Bolsa in the Northern Department of Artigas, Uruguay. A semicircular sampling area, divided in seven or eight triangular sectors was sequentially examined from October 1990 to November 1991. At Las Piedras (typical wild habitat 1063 T. rubrovaria bugs were collected from 84 of the rocky outcroops ("pedregales". Abundance varied by season peaking in October-November (spring. Throughout the year, most of the population was made up of third, fourth and fifth instar nymphs; adults were found from October to March. In the peridomestic environment of La Bolsa, however T. rubrovaria was less common and showed a more irregular instar distribution. Colonized ecotopes, were those close to houses. In both sites T. rubrovaria was mainly associated with the geckonid Homonota uruguayensis and the cockroach Blaptica dubia.

  8. The genus Macrostemum Kolenati 1859 (Trichoptera: Hydropsychidae) in the Neotropical Region: Description of two new species, taxonomic notes, distributional records and key to males.

    Science.gov (United States)

    França, Diogo; Paprocki, Henrique; Calor, Adolfo R

    2013-01-01

    The genus Macrostemum Kolenati contains 105. described species, with 15 valid species in the Neotropical region. The Adults are recognized principally by wing membranes strongly marked with dark and light colors. The Neotropical species Of Macrostemum were described based on the wing colors patterns and body morphology. In this paper we present a taxonomic study of the Neotropical species, descriptions of two new species from Brazil, distributional records and a key to males. The male of Macrostemum negrense Flint 1978 is described for the first time, Names of three Neotropical species, M. ramosum (Navás 1916), M. trigramma (Navás 1916), and M. triste (Navás 1916) are designated nomina dubia.

  9. Field validation of specific ecotoxicological tools for aquatic systems impacted with acid mine drainage

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, I.; Goncalves, F.; Nogueira, A.; Soares, A.M.V.M.; Ribeiro, R. [Instituto do Ambiente e Vida, Coimbra (Portugal). Departamento de Zoologia da Universidade de Coimbra

    2000-07-01

    Acid mine drainage (AMD) is characterised by very low pH and high heavy metal concentrations. Serious ecotoxicological effects, often leading to the complete disruption of the ecosystem, can be observed at the regions suffering this kind of contamination. Those effects can be caused either by low pH itself or by other contaminants that emerge with water acidification (mobilisation and increased solubility of heavy metals). The discrimination between the toxicity due to each of these two factors is not possible with the existing toxicity tests; the addition of chelating agents or serial dilution methods seriously alter the chemical and physical properties of the effluent. A toxicity test, based on the survival time of Ceriodaphnia dubia (Crustacea, Cladocera) neonates exposed to the unchanged effluent was developed and field validated, on an AMD contaminated site. 28 refs.

  10. Parachironomus lenz from china and Japan (Diptera, chironomidae).

    Science.gov (United States)

    Yan, Chun-Cai; Yan, Jiao; Jiang, Li; Guo, Qin; Liu, Ting; Ge, Xin-Yu; Wang, Xin-Hua; Pan, Bao-Ping

    2015-01-01

    Members of the genus Parachironomus Lenz known from China and Japan are revised, and a key to their male adults is given. Parachironomuspoyangensis sp. n. is described in this life stage. Parachironomusfrequens (Johannsen) and Parachironomusmonochromus (van der Wulp) are recorded from China for the first time, thus are redescribed from Chinese specimens. Parachironomuskamaabeus Sasa & Tanaka and Parachironomustoneabeus Sasa & Tanaka are new junior synonyms of Parachironomusfrequens. Three Chinese or Japanese species formerly placed in Parachironomus are transferred to other genera, resulting in the new combinations Cryptochironomusinafegeus (Sasa, Kitami & Suzuki), Demicryptochironomus (Irmakia) lobus (Yan, Sæther, Jin & Wang), and Microchironomuslacteipennis (Kieffer). Chironomussauteri Kieffer, Parachironomuskisobilobalis Sasa & Kondo and Parachironomuskuramaexpandus Sasa are removed from Parachironomus; the last of these three denotes a valid species of uncertain generic placement, the first two are nomina dubia.

  11. A revision of the Afrotropical species of the genus Tibellus Simon (Araneae: Philodromidae

    Directory of Open Access Journals (Sweden)

    A. Van den Berg

    1994-09-01

    Full Text Available The Afrotropical species of the genus Tibellus Simon, 1875, are revised. Of the 10 previously recognised species of long-bodied grss spiders from this region, eight are redescribed and figured. Two species, T. punctifasciatus Strand, 1906, and T. robustus Simon, 1886, are considered nomina dubia. Five new species, T. cobusi, T. gerhardi, T. nimbaensis, T. somaliensis and T. sunetae, are described and three previously recognised subspecies of T. vossioni Simon, 1884, namely T. v. armatus Lessert, 1928, T. v. flavipes Caporiacco, 1941, and T. v. minor Lessert, 1919, are given species status. The genus Tibellinus Simon, 1910, is a junior synonym of Tibellus. Tibellinus australis is transferred to the genus Tibellus. The males of T. armatus stat. nov. and T. hollidayi Lawrence, 1952, are described for the first time. A key to 17 recognised species is given. Distributional data are provided for all species.

  12. Parachironomus Lenz from China and Japan (Diptera, Chironomidae

    Directory of Open Access Journals (Sweden)

    Chuncai Yan

    2015-04-01

    Full Text Available Members of the genus Parachironomus Lenz known from China and Japan are revised, and a key to their male adults is given. Parachironomus poyangensis sp. n. is described in this life stage. Parachironomus frequens (Johannsen and P. monochromus (van der Wulp are recorded from China for the first time, thus are redescribed from Chinese specimens. Parachironomus kamaabeus Sasa & Tanaka and P. toneabeus Sasa & Tanaka are new junior synonyms of P. frequens. Three Chinese or Japanese species formerly placed in Parachironomus are transferred to other genera, resulting in the new combinations Cryptochironomus inafegeus (Sasa, Kitami & Suzuki, Demicryptochironomus (Irmakia lobus (Yan, Sæther, Jin & Wang, and Microchironomus lacteipennis (Kieffer. Chironomus sauteri Kieffer, Parachironomus kisobilobalis Sasa & Kondo and P. kuramaexpandus Sasa are removed from Parachironomus; the last of these three denotes a valid species of uncertain generic placement, the first two are nomina dubia.

  13. Assessment of ecotoxicological risks related to depositing dredged materials from canals in northern France on soil.

    Science.gov (United States)

    Perrodin, Yves; Babut, Marc; Bedell, Jean-Philippe; Bray, Marc; Clement, Bernard; Delolme, Cécile; Devaux, Alain; Durrieu, Claude; Garric, Jeanne; Montuelle, Bernard

    2006-08-01

    The implementation of an ecological risk assessment framework is presented for dredged material deposits on soil close to a canal and groundwater, and tested with sediment samples from canals in northern France. This framework includes two steps: a simplified risk assessment based on contaminant concentrations and a detailed risk assessment based on toxicity bioassays and column leaching tests. The tested framework includes three related assumptions: (a) effects on plants (Lolium perenne L.), (b) effects on aquatic organisms (Escherichia coli, Pseudokirchneriella subcapitata, Ceriodaphnia dubia, and Xenopus laevis) and (c) effects on groundwater contamination. Several exposure conditions were tested using standardised bioassays. According to the specific dredged material tested, the three assumptions were more or less discriminatory, soil and groundwater pollution being the most sensitive. Several aspects of the assessment procedure must now be improved, in particular assessment endpoint design for risks to ecosystems (e.g., integration of pollutant bioaccumulation), bioassay protocols and column leaching test design.

  14. The families Carditidae and Condylocardiidae in the Magellan and Perú-Chile provinces (Bivalvia: Carditoidea).

    Science.gov (United States)

    Güller, Marina; Zelaya, Diego G

    2013-01-01

    Based on the study of available types and extant collections, this paper provides a systematic revision of the living species of Carditoidea occurring in the Magellan and Perú-Chile Provinces. Out of the 19 nominal species reported for the area, eight species are recognized as valid: Cyclocardia compressa, C. spurca, C. thouarsii, C. velutina, Carditella naviformis, C. semen, C. tegulata and Carditopsis flabellum. Other eight nominal species are regarded as synonyms: Cardita magellanica of Cyclocardia velutina; Carditella pallida of C. tegulata; Cardita australis and Actinobolus philippi of Carditella naviformis; Cardium pygmaeum of Carditella semen; Cardita paeteliana of Cyclocardia spurca; Carditella pallida duodecimcostata of Carditopsis flabellum; and Cardita congelascens of Cyclocardia thouarsii. Furthermore, Cardita malvinae and Cardium parvulum are nomina dubia, and the occurrence of Carditella exulata in Magellanic waters is doubtful.

  15. New and remarkable records of microfungi from Turkey.

    Science.gov (United States)

    Ale-Agha, N; Feige, G B; Christiaans, B; Dündar, A E

    2003-01-01

    During a botanical excursion of the University of Essen in the year 2002 to North-, Central- and South-Anatolia we have collected representatives of about 100 genera of microfungi as parasites or saprophytes on crops and wild plants. Some of them are new for Turkey: Passalora dubia on Atriplex hortensis, Pseudocercospora ligustri on Ligustrum ovalifolium, Passalora smilacis on Smilax aspera, Uromyces limonii on Limonium spec., Puccinia jasmini on Jasminim spec., Sawadea bicornis on Acer negundo, Puccinia sii-falcariae on Falcaria vulgaris, Phomia hedericola on Hedera helix, Camorosporium pistaciae on Pistacia terebinthus, Erysiphe bahrii on Silene spec., Ramularia heraclei on Apium graveolens. All specimens are located in the Herbarium ESS, Mycotheca parva, collection G.B. Feige & N. Ale-Agha.

  16. Predator-driven trait diversification in a dragonfly genus: covariation in behavioral and morphological antipredator defense.

    Science.gov (United States)

    Mikolajewski, Dirk J; De Block, Marjan; Rolff, Jens; Johansson, Frank; Beckerman, Andrew P; Stoks, Robby

    2010-11-01

    Proof for predation as an agent shaping evolutionary trait diversification is accumulating, however, our understanding how multiple antipredator traits covary due to phenotypic differentiation is still scarce. Species of the dragonfly genus Leucorrhinia underwent shifts from lakes with fish as top predators to fishless lakes with large dragonfly predators. This move to fishless lakes was accompanied by a partial loss and reduction of larval spines. Here, we show that Leucorrhinia also reduced burst swimming speed and its associated energy fuelling machinery, arginine kinase activity, when invading fishless lakes. This results in patterns of positive phylogenetic trait covariation between behavioral and morphological antipredator defense (trait cospecialization) and between behavioral antipredator defense and physiological machinery (trait codependence). Across species patterns of trait covariation between spine status, burst swimming speed and arginine kinase activity also matched findings within the phenotypically plastic L. dubia. Our results highlight the importance of predation as a factor affecting patterns of multiple trait covariation during phenotypic diversification.

  17. Toxicity assessment of arsenic and cobalt in the presence of aquatic humic substances of different molecular sizes.

    Science.gov (United States)

    Watanabe, Cláudia Hitomi; Monteiro, Adnivia Santos Costa; Gontijo, Erik Sartori Jeunon; Lira, Vivian Silva; Bueno, Carolina de Castro; Kumar, Nirmal Tej; Fracácio, Renata; Rosa, André Henrique

    2017-05-01

    The release of contaminants in aquatic ecosystems can be influenced by humic acids. In this study, toxicity tests using environmentally relevant concentrations of arsenic and cobalt were conducted both in the presence and absence of aquatic humic substances (AHS) and the fractions of different molecular sizes in the range of (100kDa) using the microcrustacean Ceriodaphnia dubia. AHS together with arsenic reduced the toxicity, and the toxicity decreased in fractions of larger molecular size AHS. Despite the presence of cobalt, the reduction in toxicity was not observed and that depended on the molecular size of AHS. There was a trend of enhanced toxicity for Co in fractions of larger molecular sizes, opposed to that found for arsenic. Thus, the humic substances alter toxicity of trace elements, and this effect varies depending on the size of the humic substances. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Toxicity Identification Evaluation (TIE) of Belford Roxo industrial plant effluent and its contribution in water quality of downstream of Sarapui River, Iguacu River sub-basin, Baia da Guanabara Basin, RJ, Brazil; Avaliacao e identificacao da toxicidade (Toxity Identification Evaluation - TIE) do efluente liquido do polo industrial de Belford Roxo, RJ, e sua contribuicao na qualidade das aguas do corso inferior do Rio Sarapui, sub-bacia do Rio Iguacu, Bacia da Baia da Guanabara, RJ, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Pires, Luiz Eduardo Botelho

    2006-07-01

    The quality of Belford Roxo Industrial Plant effluent and water from Sarapui River were evaluated with Daphnia similis, Ceriodaphnia dubia and Danio rerio acute and chronic toxicity tests. In association with the ecotoxicological monitoring, the Toxicity Identification Evaluation procedure were performed and the identification of the toxic compounds was possible. The Chloride ion was identified as the major toxic compound in the effluent with additional effects of Metals, Ammonium and Sulfide. For the Sarapui River, the compounds of Phosphorus and Nitrogen were identified as the major toxic compounds with addictive effects of Metals, Ammonium and Sulfide. Although the environmental impact estimation based on the effluent toxicity suggests a minor impact on the water quality of Sarapui River, this was already sufficiently contaminated to make impracticable the establishment of an aquatic community. The constant discharge of untreated sludge promotes the eutrophication of this water body and makes impossible the equilibrium of this ecosystem. (author)

  19. Evaluación ecotoxicológica de sedimentos en una zona del Río Uruguay, con puntos finales indicadores de toxicidad aguda, sub-letal, crónica, reproductiva y teratogénica

    Directory of Open Access Journals (Sweden)

    Diana Míguez Carames

    2011-05-01

    Full Text Available El objetivo de este trabajo fue caracterizar la toxicidad de los sedimentos de una zona del Río Uruguay, aplicando una batería de bioensayos. Las muestras provinieron de: una zona de influencia de descargas domésticas y efluentes de una planta de celulosa (Fray Bentos, una ciudad turística aguas abajo (Las Cañas y otra aguas arriba (Nuevo Berlín, sin influencia directa de dichos vertidos. Los bioensayos aplicados en elutriados fueron: de toxicidad con Photobacterium leiognathi, de reproducción con Ceriodaphnia dubia, de teratogenicidad y letalidad con Pimephales promelas y el ensayo sub-letal en sedimento completo con Hyalella curvispina. Para evaluar la biodisponibilidad y las rutas de toxicidad, se midió el fraccionamiento del 2,4,5-triclorofenol, con resultados: 63% disuelto, 27% adsorbido sobre partículas y el resto sedimentado.Se observó toxicidad por orgánicos y metales con P. leioghnati para todos los sitios. La frecuencia de malformaciones vertebralesde P. promelas fue de 3.3% en Fray Bentos, pero C. dubia sólo mostró efectos en Nuevo Berlín y Las Cañas. Los efectos con H. curvispina se evidenciaron en todas las muestras. Las rutas de toxicidad incluirían la ingestión de contaminantes disueltos y particulados asociados a arcillas y limo. El vínculo causa-efecto para la toxicidad se continuará investigando.

  20. Cis-Golgi cisternal assembly and biosynthetic activation occur sequentially in plants and algae.

    Science.gov (United States)

    Donohoe, Bryon S; Kang, Byung-Ho; Gerl, Mathias J; Gergely, Zachary R; McMichael, Colleen M; Bednarek, Sebastian Y; Staehelin, L Andrew

    2013-05-01

    The cisternal progression/maturation model of Golgi trafficking predicts that cis-Golgi cisternae are formed de novo on the cis-side of the Golgi. Here we describe structural and functional intermediates of the cis cisterna assembly process in high-pressure frozen algae (Scherffelia dubia, Chlamydomonas reinhardtii) and plants (Arabidopsis thaliana, Dionaea muscipula; Venus flytrap) as determined by electron microscopy, electron tomography and immuno-electron microscopy techniques. Our findings are as follows: (i) The cis-most (C1) Golgi cisternae are generated de novo from cisterna initiators produced by the fusion of 3-5 COPII vesicles in contact with a C2 cis cisterna. (ii) COPII vesicles fuel the growth of the initiators, which then merge into a coherent C1 cisterna. (iii) When a C1 cisterna nucleates its first cisterna initiator it becomes a C2 cisterna. (iv) C2-Cn cis cisternae grow through COPII vesicle fusion. (v) ER-resident proteins are recycled from cis cisternae to the ER via COPIa-type vesicles. (vi) In S. dubia the C2 cisternae are capable of mediating the self-assembly of scale protein complexes. (vii) In plants, ∼90% of native α-mannosidase I localizes to medial Golgi cisternae. (viii) Biochemical activation of cis cisternae appears to coincide with their conversion to medial cisternae via recycling of medial cisterna enzymes. We propose how the different cis cisterna assembly intermediates of plants and algae may actually be related to those present in the ERGIC and in the pre-cis Golgi cisterna layer in mammalian cells. © 2013 John Wiley & Sons A/S.

  1. Integrated assessment of the impacts of agricultural drainwater in the Salinas River (California, USA)

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, B.S.; Hunt, J.W.; Phillips, B.M.; Nicely, P.A.; Vlaming, V. de; Connor, V.; Richard, N.; Tjeerdema, R.S

    2003-08-01

    Invertebrate mortality was correlated with levels of water and sediment contaminatioin in the Salinas River. - The Salinas River is the largest of the three rivers that drain into the Monterey Bay National Marine Sanctuary in central California. Large areas of this watershed are cultivated year-round in row crops and previous laboratory studies have demonstrated that acute toxicity of agricultural drainwater to Ceriodaphnia dubia is caused by the organophosphate (OP) pesticides chlorpyrifos and diazinon. In the current study, we used a combination of ecotoxicologic tools to investigate incidence of chemical contamination and toxicity in waters and sediments in the river downstream of a previously uncharacterized agricultural drainage creek system. Water column toxicity was investigated using a cladoceran C. dubia while sediment toxicity was investigated using an amphipod Hyalella azteca. Ecological impacts of drainwater were investigated using bioassessments of macroinvertebrate community structure. The results indicated that Salinas River water downstream of the agricultural drain is acutely toxic to Ceriodaphnia, and toxicity to this species was highly correlated with combined toxic units (TUs) of chlorpyrifos and diazinon. Laboratory tests were used to demonstrate that sediments in this system were acutely toxic to H. azteca, which is a resident genus. Macroinvertebrate community structure was moderately impacted downstream of the agricultural drain input. While the lowest macroinvertebrate abundances were measured at the station demonstrating the greatest water column and sediment toxicity and the highest concentrations of pesticides, macroinvertebrate metrics were more significantly correlated with bank vegetation cover than any other variable. Results of this study suggest that pesticide pollution is the likely cause of laboratory-measured toxicity in the Salinas River samples and that this factor may interact with other factors to impact the

  2. Predicting toxic effects of copper on aquatic biota in mineralized areas by using the Biotic Ligand Model

    Science.gov (United States)

    Smith, Kathleen S.; Ranville, James F.; Adams, M.; Choate, LaDonna M.; Church, Stan E.; Fey, David L.; Wanty, Richard B.; Crock, James G.

    2006-01-01

    The chemical speciation of metals influences their biological effects. The Biotic Ligand Model (BLM) is a computational approach to predict chemical speciation and acute toxicological effects of metals on aquatic biota. Recently, the U.S. Environmental Protection Agency incorporated the BLM into their regulatory water-quality criteria for copper. Results from three different laboratory copper toxicity tests were compared with BLM predictions for simulated test-waters. This was done to evaluate the ability of the BLM to accurately predict the effects of hardness and concentrations of dissolved organic carbon (DOC) and iron on aquatic toxicity. In addition, we evaluated whether the BLM and the three toxicity tests provide consistent results. Comparison of BLM predictions with two types of Ceriodaphnia dubia toxicity tests shows that there is fairly good agreement between predicted LC50 values computed by the BLM and LC50 values determined from the two toxicity tests. Specifically, the effect of increasing calcium concentration (and hardness) on copper toxicity appears to be minimal. Also, there is fairly good agreement between the BLM and the two toxicity tests for test solutions containing elevated DOC, for which the LC50 is 3-to-5 times greater (less toxic) than the LC50 for the lower-DOC test water. This illustrates the protective effects of DOC on copper toxicity and demonstrates the ability of the BLM to predict these protective effects. In contrast, for test solutions with added iron there is a decrease in LC50 values (increase in toxicity) in results from the two C. dubia toxicity tests, and the agreement between BLM LC50 predictions and results from these toxicity tests is poor. The inability of the BLM to account for competitive iron binding to DOC or DOC fractionation may be a significant shortcoming of the BLM for predicting site- specific water-quality criteria in streams affected by iron-rich acidic drainage in mined and mineralized areas.

  3. The chronic toxicity of sodium bicarbonate, a major component of coal bed natural gas produced waters

    Science.gov (United States)

    Farag, Aida M.; Harper, David D.

    2014-01-01

    Sodium bicarbonate (NaHCO3) is the principal salt in coal bed natural gas produced water from the Powder River Structural Basin, Wyoming, USA, and concentrations of up to 3000 mg NaHCO3/L have been documented at some locations. No adequate studies have been performed to assess the chronic effects of NaHCO3 exposure. The present study was initiated to investigate the chronic toxicity and define sublethal effects at the individual organism level to explain the mechanisms of NaHCO3 toxicity. Three chronic experiments were completed with fathead minnows (Pimephales promelas), 1 with white suckers (Catostomus commersoni), 1 with Ceriodaphnia dubia, and 1 with a freshwater mussel, (Lampsilis siliquoidea). The data demonstrated that approximately 500 mg NaHCO3/L to 1000 mg NaHCO3/L affected all species of experimental aquatic animals in chronic exposure conditions. Freshwater mussels were the least sensitive to NaHCO3 exposure, with a 10-d inhibition concentration that affects 20% of the sample population (IC20) of 952 mg NaHCO3/L. The IC20 for C. dubia was the smallest, at 359 mg NaHCO3/L. A significant decrease in sodium–potassium adenosine triphosphatase (Na+/K+ ATPase) together with the lack of growth effects suggests that Na+/K+ ATPase activity was shut down before the onset of death. Several histological anomalies, including increased incidence of necrotic cells, suggested that fish were adversely affected as a result of exposure to >450 mg NaHCO3/L.

  4. Evaluation of the Biotic Ligand Model relative to other site-specific criteria derivation methods for copper in surface waters with elevated hardness.

    Science.gov (United States)

    Van Genderen, Eric; Gensemer, Robert; Smith, Carrie; Santore, Robert; Ryan, Adam

    2007-08-30

    The goal of this study was to evaluate the reliability of the Biotic Ligand Model to predict Cu toxicity in very hard surface water (>200 mg/L as CaCO(3)), relative to current copper criteria methodologies (hardness-based equation and the water-effect ratio; WER). To test these methods, we conducted acute Cu toxicity tests with three aquatic test species (Ceriodaphnia dubia, Daphnia pulex and Pimephales promelas) in seven surface waters. The sites were representative of effluent-dependent or effluent-dominated streams common to the arid western United States of America (arid West) and a wide range of water quality variables were tested. In addition, concurrent Cu toxicity tests were conducted in laboratory waters that were matched to hardness and alkalinity of the sites to facilitate calculation of WER values. Results were used to characterize empirical relationships between water quality characteristics and Cu toxicity, and to compare measured Cu toxicity with Biotic Ligand Model (BLM) predictions. Acute toxicity tests were also conducted with C. dubia and P. promelas in a range of Ca or Mg-dominated hardness concentrations to determine the independent effects of Ca or Mg on Cu toxicity at high hardness levels. Conclusions from this study suggest that the BLM generates appropriate criteria for the waters tested in this study when compared to the hardness-based equation or WER approach. Although the historical site-specific methods are useful for surface waters with hardness alkalinity, Ca, Mg and Na). Therefore, the BLM offers an improved alternative to the hardness-based and WER approaches, particularly for situations where the current methods would be under-protective of sensitive aquatic life.

  5. Hypertrehalosaemic neuropeptides decrease levels of the glycolytic signal fructose 2,6-bisphosphate in cockroach fat body

    Science.gov (United States)

    Becker; Wegener

    1998-05-21

    In cockroach fat body, trehalogenesis and glycolysis compete for glucose phosphates as common substrates. During trehalogenesis, glycolysis is inhibited, although the mechanism responsible for this is not known. Incubation of the isolated fat body from the Argentine cockroach Blaptica dubia with an extract of the corpora cardiaca containing as little as 0.005 gland equivalents ml-1 of incubation medium increased the release of trehalose (anthrone-positive material) from the tissue by more than 100 %. The content of the glycolytic activator fructose 2,6-bisphosphate was decreased by up to 50 %. A decapeptide was isolated from the corpora cardiaca of B. dubia and shown to be identical to the naturally occurring Blaberus discoidalis hypertrehalosaemic peptide (Bld HrTH), which was also found in the corpora cardiaca. Synthetic Bld HrTH at 2 nmol l-1 and above increased trehalose production and decreased the content of fructose 2,6-bisphosphate to the same extent as did corpus cardiacum extract. The octapeptides Periplaneta americana cardioacceleratory hormones I and II (Pea CAH-I and Pea CAH-II) also had a significant effect on both parameters. Fructose 2,6-bisphosphate is a potent activator of phosphofructokinase from cockroach fat body if the enzyme is assayed at near-physiological concentrations of substrates and effectors. It is suggested that, because of the decrease in fructose 2,6-bisphosphate levels in the fat body, the activity of the key glycolytic enzyme phosphofructokinase is diminished. This can explain the inhibition of glycolytic flux by hypertrehalosaemic peptides which alters the balance of glucose metabolism in favour of trehalose formation.

  6. The complete mitochondrial genomes of four cockroaches (Insecta: Blattodea) and phylogenetic analyses within cockroaches.

    Science.gov (United States)

    Cheng, Xue-Fang; Zhang, Le-Ping; Yu, Dan-Na; Storey, Kenneth B; Zhang, Jia-Yong

    2016-07-15

    Three complete mitochondrial genomes of Blaberidae (Insecta: Blattodea) (Gromphadorhina portentosa, Panchlora nivea, Blaptica dubia) and one complete mt genome of Blattidae (Insecta: Blattodea) (Shelfordella lateralis) were sequenced to further understand the characteristics of cockroach mitogenomes and reconstruct the phylogenetic relationship of Blattodea. The gene order and orientation of these four cockroach genomes were similar to known cockroach mt genomes, and contained 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and one control region. The mt genomes of Blattodea exhibited a characteristics of a high A+T composition (70.7%-74.3%) and dominant usage of the TAA stop codon. The AT content of the whole mt genome, PCGs and total tRNAs in G. portentosa was the lowest in known cockroaches. The presence of a 71-bp intergenic spacer region between trnQ and trnM was a unique feature in B. dubia, but absent in other cockroaches, which can be explained by the duplication/random loss model. Based on the nucleotide and amino acid datasets of the 13 PCGs genes, neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and bayesian inference (BI) analyses were used to rebuild the phylogenetic relationship of cockroaches. All phylogenetic analyses consistently placed Isoptera as the sister cluster to Cryptocercidae of Blattodea. Ectobiidae and Blaberidae (Blaberoidea) formed a sister clade to Blattidae. Corydiidae is a sister clade of all the remaining cockroach species with a high value in NJ and MP analyses of nucleotide and amino acid datasets, and ML and BI analyses of the amino acid dataset.

  7. On a pterosaur jaw from the Upper Jurassic of Tendaguru (Tanzania

    Directory of Open Access Journals (Sweden)

    D. M. Unwin

    1999-01-01

    Full Text Available A short section of a mandibular symphysis is the first cranial fossil of a pterosaur to be reported from the Upper Jurassic of Tendaguru, Tanzania. It is made the holotype of a new dsungaripteroid pterosaur, Tendaguripterus recki n. gen. n. sp. All previously named pterosaur taxa from Tendaguru are shown to be nomina dubia. The pterosaur assemblage from Tendaguru contains a "rhamphorhynchoid", as well as the dsungaripteroid, and is similar in its systematic composition to other Late Jurassic pterosaur assemblages from Laurasia. The diversity and broad distribution of dsungaripteroids in the Late Jurassic suggests that the group was already well established by this time. Der erste Schädelrest eines Flugsauriers aus dem Oberjura von Tendaguru in Tansania wird beschrieben. Bei dem Fundstück handelt es sich um ein bezahntes Unterkieferbruchstück aus der Symphysenregion. Der Fund gehört zu einem neuen Taxon, das als Tendaguripterus recki n. gen. n. sp. bezeichnet und zur Überfamilie Dsungaripteroidea gestellt wird. Alle zuvor aus den Tendaguru-Schichten beschriebenen Taxa werden als nomina dubia angesehen. In Tendaguru sind Verteter der „Rhamphorhynchoidea“ und Dsungaripteroidea nachgewiesen. Diese systematische Zusammensetzung ist derjenigen anderer Flugsaurier-Vergesellschaftungen der späten Jura-Zeit ähnlich. Die Vielfalt und die weite Verbreitung der Dsungaripteroidea in Laurasia läßt darauf schließen, daß sich diese Flugsauriergruppe bereits in der späten Jura-Zeit erfolgreich durchgesetzt hatte. doi:10.1002/mmng.1999.4860020109

  8. Paratrygon aiereba (Müller & Henle, 1841: the senior synonym of the freshwater stingray disceus thayeri Garman, 1913 (chondrichthyes: potamotrygonidae

    Directory of Open Access Journals (Sweden)

    Ricardo S. Rosa

    1990-01-01

    Full Text Available A review of the original descriptions and available types of the South American freshwater stingrays Trygon aiereba Müller & Henle, 1841, Trygon strogylopterus Schomburgk, 1843 and Disceus thayeri Garman, 1913 indicates that these three nominal species are synonymous. The senior name, placed in the monotypic genus Paratrygon Duméril, 1865, established for Trygon aiereba, is available and valid. Based on its description, T. aiereba is a freshwater stingray. Therefore, this taxon is not the same as Raja ajereba Walbaum and Raja orbicularis Schneider, both names established for the marine "Aiereba" of Marcgrave, and which preferably should be treated as nomina dubia. Paratrygon does not replace Potamotrygon Garman, 1877 as the type genus, because the family name Potamotrygonidae Garman, 1877 has priority over Paratrygonidade Gill, 1893.A revisão das descrições originais e dos tipos existentes das raias de água doce Trygon aiereba Müller & Henle, 1841, Trygon strogylopterus Schomburgk, 1843, e Disceus thayeri Garman, 1913, indica que essas três espécies nominais são sinônimas. O nome sênior, colocado no gênero monotípico Paratrygon Duméril, 1865, estabelecido para T. aiereba, é disponível e válido. A descrição de T. aiereba corresponde claramente a uma raia de agua doce; portanto esta espécie não é um sinônimo de Raja ajereba Walbaum e de Raja orbicularis Schneider, ambos os nomes propostos para a "Aiereba " marinha de Marcgrave, e que preferivelmente devem ser tratados como nomina dubia. Paratrygon não substitui Potamotrygon Garman, 1877 como gênero-tipo, porque o nome de família Potamotrygonidae Garman, 1877 tem prioridade sobre Paratrygonidae Gill. 1893.

  9. Ecotoxicological assessment of the pharmaceutical compound Triclosan to freshwater invertebrates with emphasis to spiked sediment tests; Avaliacao ecotoxicologica do farmaco Triclosan para invertebrados de agua doce com enfase em ensaios com sedimento marcado ('spiked sediment')

    Energy Technology Data Exchange (ETDEWEB)

    Pusceddu, Fabio Hermes

    2009-07-01

    The increasing of Pharmaceutical and Personal Care Products (PPCPs) occurrence in the aquatic environment cause adverse effects on the human health and aquatic communities. The environmental risk of the PPCPs associated with the possibility of synergic effects between PCPPs and the increase of the use of synthetic organic compounds, unchained a great concern on the toxic potential to biota aquatic. Triclosan (5-chloro-2-(2,4-dichlorophenoxy)-phenol) is a pharmaceutical compound widely used due your antibacterial mechanism effect, found in at least 932 products such as shampoos, toilet soaps, deodorants, lotions, toothpaste, detergents, socks and underwear, among others. Currently, studies about the Triclosan toxicity in the water and, mainly in the sediment, are poorly. We have the knowledge that the photodegradation of this product results into dichlorodibenzo-p-dioxin, and now it has great discussion on environmental agencies, like EPA, about the release or restriction of this product. The aim of this work is to assess the effects of Triclosan on mortality of insect larvae Chironomus xanthus and mortality and reproduction inhibition of microcrustacea Ceriodaphnia dubia exposed to Triclosan spiked sediments based on standard methods EPA and OECD. The EC50;96H obtained on acute toxicity tests with C. xanthus was 45,26 mg.Kg{sup -1}. The chronic toxicity tests with C. dubia using spiked sediments were performed following the procedure in Burton and MacPherson (1995). A no-observed-effect concentrations and lowest-observed-effect concentration were 5,78 e 6,94 mg.Kg{sup -1}, respectively. (author)

  10. Toxicity on crustaceans and endocrine disrupting activity on Saccharomyces cerevisiae of eight alkylphenols.

    Science.gov (United States)

    Isidori, Marina; Lavorgna, Margherita; Nardelli, Angela; Parrella, Alfredo

    2006-06-01

    In the last few years many concerns have been raised regarding the environmental safety of alkylphenol polyethoxylate surfactants (APnEOs). They are widely used in detergents, paints, herbicides and many other formulated products. It has been estimated that 60% of APnEOs end up in the aquatic environment; they are biodegradable and transformed into alkylphenols, such as nonylphenol and octylphenol that are hydrophobic and tend to accumulate. In the present study, acute and chronic aquatic toxicity and the estrogenic activity of the following eight alkylphenols were assessed: 4-nonylphenol, 4-octylphenol, 4-nonylphenol-10-ethoxylate, 4-tert-octylphenol, POE (1 to 2)-nonylphenol, POE (6)-nonylphenol, POE (3)-tert-octylphenol and POE (9 to 10)-tert-octylphenol. The toxic potential was measured on the crustaceans Daphnia magna and Ceriodaphnia dubia, while the estrogenic activity was determined by using the YES-test with the strain Saccharomyces cerevisiae RMY326. The results showed that the exposure of crustaceans to the eight xenoestrogens investigated caused both acute and chronic effects. The EC50 values found for C. dubia at 48 h were compared to D. magna at 24h and, gave a first indication about the toxic activity of the compounds investigated, that is better expressed in the long-term. In fact, chronic data showed a strong increase in toxicity with EC50 values one or two orders of magnitude lower than the acute values. The results of the YES-test showed that nonylphenol, octylphenol and 4-tert-octylphenol were the most estrogenic and the bioassay was able to detect their estrogenicity at very low concentrations (ng-microg/l).

  11. Novas citações de Chytridiomycota e Oomycota para o Parque Estadual das Fontes do Ipiranga (PEFI, SP, Brasil New records of Chytridiomycota and Oomycota from the "Parque Estadual das Fontes do Ipiranga (PEFI", SP, Brazil

    Directory of Open Access Journals (Sweden)

    Carmen Lidia Amorim Pires-Zottarelli

    2007-03-01

    Full Text Available Levantamento de fungos zoospóricos realizado em lagos artificiais do Parque Estadual das Fontes do Ipiranga (PEFI, situado na cidade de São Paulo, Estado de São Paulo, Brasil, resultou no isolamento de 41 táxons, sendo 36 identificados em nível específico. Vinte e três táxons pertencem ao Reino Fungi, filo Chytridiomycota, ordens Chytridiales, Monoblepharidales e Spizellomicetales e, 18 ao Reino Straminipila, filo Oomycota, ordens Saprolegniales e Peronosporales. Dentre os fungos isolados, 14 são mencionados pela primeira vez para o PEFI: Aphanomyces helicoides von Minden, Catenochytridium kevorkianii Sparrow, Catenochytridium sp., Chytriomyces appendiculatus Karling, C. aureus Karling, C. hyalinus Karling, C. spinosus Fay, Diplophlyctis asteroidea Dogma, D. complicata (Willoughby Dogma, Karlingia dubia Karling, Nowakowskiella hemisphaerospora Shanor, Saprolegnia australis Elliott, Septochytrium variabile Berdan e Truittella sp., os quais são descritos, comentados e ilustrados. O gênero Truitella é mencionado pela primeira vez para o Brasil.A survey of zoosporic fungi from artificial lakes of the Fontes do Ipiranga State Park, in the city of São Paulo, São Paulo State, Brazil, yielded the isolation of 41 taxa with 36 species. Twenty-three taxa belong to Chytridiales, Monoblepharidales and Spizellomycetales of the Phylum Chytridiomycota, Fungi Kingdom and 18 belong to Saprolegniales and Peronosporales, Phylum Oomycota, Straminipila Kingdom. Of these, 14 are first-time records for this State Park: Aphanomyces helicoides von Minden, Catenochytridium kevorkianii Sparrow, Catenochytridium sp., Chytriomyces appendiculatus Karling, C. aureus Karling, C. hyalinus Karling, C. spinosus Fay, Diplophlyctis asteroidea Dogma, D. complicata (Willoughby Dogma, Karlingia dubia Karling, Nowakowskiella hemisphaerospora Shanor, Saprolegnia australis Elliott, Septochytrium variabile Berdan and Truittella sp., which are described, commented and

  12. Industrial safety and applied health physics. Annual report for 1980

    Energy Technology Data Exchange (ETDEWEB)

    1981-11-01

    Information is reported in sections entitled: radiation monitoring; Environmental Management Program; radiation and safety surveys; industrial safety and special projects; Office of Operational Safety; and training, lectures, publications, and professional activities. There were no external or internal exposures to personnel which exceeded the standards for radiation protection as defined in DOE Manual Chapter 0524. Only 35 employees received whole body dose equivalents of 10 mSv (1 rem) or greater. There were no releases of gaseous waste from the Laboratory which were of a level that required an incident report to DOE. There were no releases of liquid radioactive waste from the Laboratory which were of a level that required an incident report to DOE. The quantity of those radionuclides of primary concern in the Clinch River, based on the concentration measured at White Oak Dam and the dilution afforded by the Clinch River, averaged 0.16 percent of the concentration guide. The average background level at the Perimeter Air Monitoring (PAM) stations during 1980 was 9.0 ..mu..rad/h (0.090 ..mu..Gy/h). Soil samples were collected at all perimeter and remote monitoring stations and analyzed for eleven radionuclides including plutonium and uranium. Plutonium-239 content ranged from 0.37 Bq/kg (0.01 pCi/g) to 1.5 Bq/kg (0.04 pCi/g), and the uranium-235 content ranged from 0.7 Bq/kg (0.02 pCi/g) to 16 Bq/kg (0.43 pCi/g). Grass samples were collected at all perimeter and remote monitoring stations and analyzed for twelve radionuclides including plutonium and uranium. Plutonium-239 content ranged from 0.04 Bq/kg (0.001 pCi/g) to 0.07 Bq/kg (0.002 pCi/g), and the uranium-235 content ranged from 0.37 Bq/kg (0.01 pCi/g) to 12 Bq/kg (0.33 pCi/g).

  13. Task 3 Report - PCBs in the Environment Near the Oak Ridge Reservation - A Reconstruction of Historical Doses and Health Risks

    Energy Technology Data Exchange (ETDEWEB)

    Price, Paul S; Widner, Thomas; Bonnevie, Nancy; Schmidt, Charlie; McCrodden-Hamblen, Jane; Vantaggio, Joanne; Gwinn, Patrick

    1999-07-01

    This report presents the results of an in-depth assessment of historical releases of polychlorinated biphenyls (PCBs) from the Oak Ridge Reservation (ORR) and risks of adverse health effects in local populations. The study was conducted by ChemRisk, a service of McLaren/Hart, Inc., for the Tennessee Department of Health. The project team (1) investigated releases of PCBs from the government sites, (2) evaluated PCB levels in environmental media in the area, (3) described releases of PCBs from other sources in the area, and (4) evaluated potential human exposures and health impacts associated with the historical presence of these contaminants in the environment. Beginning in the 1940s, PCBs were used extensively on the ORR and throughout the U.S. as a fire retardant in electrical components. PCBs were also used as cutting fluids for lubrication and cooling during metal working operations. Using information specific to the ORR, the project team estimated health risks for five off-site populations: (1) farm families that raised beef, dairy cattle, and vegetables on the flood plain of East Fork Poplar Creek (EFPC); (2) individuals who may have purchased beef and milk from cattle raised in the EFPC flood plain; (3) commercial and recreational fish consumers; (4) individuals that may have consumed turtles; and (5) users of surface water for recreation. Noteworthy features of the study include a two-dimensional analysis of uncertainty and variability in the non-cancer risk estimates and an assessment of the uncertainty in PCB toxicology thresholds. Conservative estimates of cancer risks from the ORR releases of PCBs to consumers of fish from Watts Bar Reservoir and the Clinch River range from less than 1 in a 1,000,000 to 2 in 10,000. Three or less excess cases of cancer would be expected to occur among individuals who consumed fish from these local waters since the 1940's. Persons who consumed large amounts of fish from the Clinch R. and Watts Bar were also at risk

  14. A mechanistic approach to link biological effects of radioactive substances from molecules to populations in wildlife species - A mechanistic approach to link biological effects of radionuclides from molecules to populations in wildlife species

    Energy Technology Data Exchange (ETDEWEB)

    Alonzo, Frederic; Parisot, Florian; Plaire, Delphine; Adam-Guillermin, Christelle; Garnier- Laplace, Jacqueline [Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, LECO, Cadarache, Saint-Paul- Lez-Durance, 13115 (France)

    2014-07-01

    of action was confirmed by measurements of assimilation reduction and observations of histological alteration of the digestive epithelium. However the mechanisms involved in the trans-generational increase in sensitivity remained unknown. A recent study investigated DNA damage in daphnids exposed to uranium, demonstrating that molecular alterations were accumulated in females over the course of exposure and transmitted to their progeny. Such alterations were interpreted as the underlying mechanism causing the increase in effect severity over generations and are now investigated during exposures to Cs-137 and, as a future perspective, to Am-241. A DEBtox model considering the accumulation and transmission of genetic damage was used to analyse radionuclides effects on life history in daphnids exposed over successive generations. Modelling outcomes were projected to the population level using Leslie matrices, in order to explore ecological consequences of exposure to radionuclides at a relevant scale for biota protection. (authors)

  15. Zooplankton communities in a large prealpine lake, Lake Constance: comparison between the Upper and the Lower Lake

    Directory of Open Access Journals (Sweden)

    Gerhard MAIER

    2005-08-01

    Full Text Available The zooplankton communities of two basins of a large lake, Lake Constance, were compared during the years 2002 and 2003. The two basins differ in morphology, physical and chemical conditions. The Upper Lake basin has a surface area of 470 km2, a mean depth of 100 and a maximum depth of 250 m; the Lower Lake basin has a surface area of 62 km2, a mean depth of only 13 and a maximum depth of 40 m. Nutrient, chlorophyll-a concentrations and mean temperatures are somewhat higher in the Lower than in the Upper Lake. Total abundance of rotifers (number per m2 lake surface was higher and rotifer development started earlier in the year in the Lower than in the Upper Lake. Total abundance of crustaceans was higher in the Upper Lake in the year 2002; in the year 2003 no difference in abundance could be detected between the lake basins, although in summer crustacean abundance was higher in the Lower than in the Upper Lake. Crustacean communities differed significantly between lake basins while there was no apparent difference in rotifer communities. In the Lower Lake small crustaceans, like Bosmina spp., Ceriodaphnia pulchella and Thermocyclops oithonoides prevailed. Abundance (number per m2 lake surface of predatory cladocerans, large daphnids and large copepods was much lower in the Lower than in the Upper Lake, in particular during the summer months. Ordination with nonmetric multidimensional scaling (NMS separated communities of both lakes along gradients that correlated with temperature and chlorophyll a concentration. Clutches of copepods were larger in the Lower than in the Upper Lake. No difference could be detected in clutch size of large daphnids between lake basins. Our results show that zooplankton communities in different basins of Lake Constance can be very different. They further suggest that the lack of large crustaceans in particular the lack of large predatory cladocerans in the Lower Lake can have negative effects on growth and

  16. Incorporation of gypsum waste in ceramic block production: Proposal for a minimal battery of tests to evaluate technical and environmental viability of this recycling process.

    Science.gov (United States)

    Godinho-Castro, Alcione P; Testolin, Renan C; Janke, Leandro; Corrêa, Albertina X R; Radetski, Claudemir M

    2012-01-01

    Civil engineering-related construction and demolition debris is an important source of waste disposed of in municipal solid waste landfills. After clay materials, gypsum waste is the second largest contributor to the residential construction waste stream. As demand for sustainable building practices grows, interest in recovering gypsum waste from construction and demolition debris is increasing, but there is a lack of standardized tests to evaluate the technical and environmental viability of this solid waste recycling process. By recycling gypsum waste, natural deposits of gypsum might be conserved and high amounts of the waste by-product could be reused in the civil construction industry. In this context, this paper investigates a physical property (i.e., resistance to axial compression), the chemical composition and the ecotoxicological potential of ceramic blocks constructed with different proportions of clay, cement and gypsum waste, and assesses the feasibility of using a minimal battery of tests to evaluate the viability of this recycling process. Consideration of the results for the resistance to axial compression tests together with production costs revealed that the best formulation was 35% of plastic clay, 35% of non-plastic clay, 10% of Portland cement and 20% of gypsum waste, which showed a mean resistance of 4.64MPa. Energy dispersive X-ray spectrometry showed calcium and sulfur to be the main elements, while quartz, gypsum, ettringite and nacrite were the main crystalline compounds found in this formulation. Ecotoxicity tests showed that leachate from this formulation is weakly toxic toward daphnids and bacteria (EC(20%)=69.0 and 75.0, respectively), while for algae and fish the leachate samples were not toxic at the EC(50%) level. Overall, these results show that the addition of 20% of gypsum waste to the ceramic blocks could provide a viable substitute for clay in the ceramics industry and the tests applied in this study proved to be a useful tool

  17. Efficiency of removing nitrogen and phosphorous and effects on extracellular enzyme activity in water body by five hydrophytes%5种水生植物的脱氮除磷效果及其对水体胞外酶活的影响

    Institute of Scientific and Technical Information of China (English)

    汪文强; 王子芳; 高明

    2016-01-01

    To investigate the role of hydrophytes in the purification of eutrophic water bodies,Trapa quadrispinosa Roxb.,Eichhornia crassipes,Hydrocharis dubia (Bl.) Backer,Ipomoea aquatica Forsk,and Lemna minor L.were planted in treated water to compare their effects on purification and their influence on extracellular enzyme activity.The results showed that all hydrophytes performed well during the purification process.For total nitrogen (TN),the order of removal efficiency was Eichhornia crassipes (81.6%) > Ipomoea aquatica Forsk (72.2%) > Hydrocharis dubia (Bl.) Backer (68.4%) > Trapa quadrispinosa Roxb.(65.8%) > Lemna minor L.(60.2%),and for total phosphorous (TP) removal,the order was Eichhornia crassipes (95.0%) > Ipomoea aquatica Forsk (89.7%) > Hydrocharis dubia (Bl.) Backer (78.4%) > Trapa quadrispinosa Roxb.(77.3%) > Lemna minor L.(70.5%).All five hydrophytes could enhance the activity of extracellular enzymes,and the treatment involving E.crassipes showed the maximum range and peak urease activity (UA) and alkaline phosphatase activity (APA).The range and peak UA were 19.70 μg · mL-1 and 10.33 μg · mL-1,respectively,and for APA,they were 8.12 μg · mL-1 and 5.95 μg · mL-1.The range and peak UA and APA for Ipomoea aquatica Forsk were the next highest.UA and APA were significantly negatively correlated with the concentrations of both NH4-N and dissolved active phosphorus (SRP),and the correlations were between-0.853 and-0.992 and -0.813 and-0.994,respectively.Eichhornia crassipes and Ipomoea aquatica Forsk may work better than Trapa quadrispinosa Roxb,Hydrocharis dubia (Bl.) Backer and Lemna minor L.,and have potential for application in the purification of eutrophic water bodies.%利用静态小区实验研究了菱角(Trapa quadrispinosa Roxb.)、凤眼莲(Eichhornia crassipes.)、水鳖(Hydrocharis dubia (Bl.) Backer)、空心菜(Ipomoea aquatica Forsk)和青萍(Lemna minor L.)5种不同植物对富营养水体的净

  18. Isolated thoracic (D5 intramedullary epidermoid cyst without spinal dysraphism: A rare case report

    Directory of Open Access Journals (Sweden)

    Sudhansu Sekhar Mishra

    2015-01-01

    Full Text Available Spinal epidermoid cyst, congenital or acquired, is mainly congenital associated with spinal dysraphism, rarely in isolation. Intramedullary epidermoid cysts (IECs are rare with less than 60 cases reported so far; isolated variety (i.e., without spinal dysraphism is still rarer. Complete microsurgical excision is the dictum of surgical treatment. A 14-year-old boy presented with 4-month history of upper backache accompanied with progressive descending paresthesia with paraparesis with early bladder and bowel involvement. His condition deteriorated rapidly making him bedridden. Neurological examination revealed upper thoracic myeloradiculopathy probably of neoplastic origin with sensory localization to D5 spinal level. Digital X-ray revealed no feature suggestive of spinal dysraphism. Contrast magnetic resonance imaging (MRI characteristics clinched the presumptive diagnosis. Near-total microsurgical excision was done leaving behind a small part of the calcified capsule densely adhered to cord. Histopathological features were confirmative of an epidermoid cyst. Postoperatively, he improved significantly with a gain of motor power sufficient to walk without support within a span of 6 months. Spinal IECs, without any specific clinical presentation, are often diagnosed based upon intraoperative and histopathological findings, however early diagnosis is possible on complete MRI valuation. Complete microsurgical excision, resulting in cessation of clinical progression and remission of symptoms, has to be limited to sub-total or near-total excision if cyst is adherent to cord or its confines.

  19. Ant Foraging Behavior for Job Shop Problem

    Directory of Open Access Journals (Sweden)

    Mahad Diyana Abdul

    2016-01-01

    Full Text Available Ant Colony Optimization (ACO is a new algorithm approach, inspired by the foraging behavior of real ants. It has frequently been applied to many optimization problems and one such problem is in solving the job shop problem (JSP. The JSP is a finite set of jobs processed on a finite set of machine where once a job initiates processing on a given machine, it must complete processing and uninterrupted. In solving the Job Shop Scheduling problem, the process is measure by the amount of time required in completing a job known as a makespan and minimizing the makespan is the main objective of this study. In this paper, we developed an ACO algorithm to minimize the makespan. A real set of problems from a metal company in Johor bahru, producing 20 parts with jobs involving the process of clinching, tapping and power press respectively. The result from this study shows that the proposed ACO heuristics managed to produce a god result in a short time.

  20. Report of the Attorney General to the Safe Growth Cabinet Council

    Energy Technology Data Exchange (ETDEWEB)

    Cody, W.J.

    1985-09-23

    On January 7, 1983, President Reagan signed into law the Nuclear Waste Policy Act (NWPA), 42 U.S.C. {section} 10101 et seq. As part of the Act, the Congress of the United States authorized construction of a permanent deep geologic repository in an effort to solve the nation`s problem with disposal of spent nuclear fuel and high-level radioactive waste. Congress also directed the Department of Energy (DOE) to study the need for and feasibility of constructing a monitored retrievable storage (MRS) facility. Also in late April of 1985, the State of Tennessee was informed that three potential sites for the MRS had been selected in Tennessee. The locations included the site of the abandoned Clinch River Breeder Reactor Project, a site on DOE`s Oak Ridge Reservation, and the site of the abandoned Hartsville nuclear power plant. This report covers the legal aspects of the potential project completed during the period September 1, 1985--November 30, 1985.