Sample records for earthworm avoidance test

  1. THE POTENTIAL OF AN EARTHWORM AVOIDANCE TEST FOR EVALUATION OF HAZARDOUS WASTE SITES

    EPA Science Inventory

    An earthworm avoidance test has potential advantages for use in evaluation of hazardous wastes sites. Because organisms often exhibit behavioral responses at lower levels of stress than those that acute toxicity tests are able to detect, avoidance tests could provide increased se...

  2. The potential of an earthworm avoidance test for evaluation of hazardous waste sites

    SciTech Connect

    Yeardley, R.B. Jr.; Gast, L.C. [DynCorp, Cincinnati, OH (United States); Lazorchak, J.M. [Environmental Protection Agency, Cincinnati, OH (United States)

    1996-09-01

    An earthworm avoidance test has potential advantages for use in evaluation of hazardous wastes sites. Because organisms often exhibit behavioral responses at lower levels of stress than those that acute toxicity tests are able to detect, avoidance tests could provide increased sensitivity to hazardous chemicals. Avoidance is an ecologically relevant endpoint that neither acute nor sublethal tests measure. Avoidance can potentially indicate sublethal stress in a short period of time, testing is easily done in a soil matrix, and an avoidance test has the potential for specialized applications for soil testing. Dual-control test data established that, in absence of a toxicant, worms did not congregate, but instead distributed themselves fairly randomly with respect to the two sides of the test chambers, that is, they did not display behavior that might be mistaken for avoidance. In tests with artificial soil spiked with reference toxicants and hazardous site soils, worms avoided soils containing various toxic chemicals. Avoidance behavior proved in most cases be a more sensitive indicator of chemical contamination than acute tests. Determination of avoidance was possible in 1 to 2 d, much less than the current duration of acute and sublethal earthworm tests.

  3. Earthworm avoidance of biochar can be mitigated by wetting , William C. Hockaday b

    E-print Network

    Alvarez, Pedro J.

    Earthworm avoidance of biochar can be mitigated by wetting Dong Li a , William C. Hockaday b Keywords: Eisenia foetida Avoidance test Biochar Desiccation MDA SOD PAH a b s t r a c t Biochar has and mitigate any unintended consequences associated with soil biochar amendment. We conducted soil avoidance

  4. Use of Avoidance Tests for Investigating Potential of the Earthworm Eisenia fetida to Improve Composting of Grass Clippings

    Microsoft Academic Search

    P. Illmer; M. Liebensteiner

    2011-01-01

    The earthworm Eisenia fetida is the most commonly used worm for worm-supported composting of organic residues. Within the present study, the potential of E. fetida for decomposing grass clippings, an organic waste which usually causes anoxic conditions and thus insufficient degradation in the course of common composting, was investigated. To enable a thorough investigation, the substrate-related requirements of E. fetida

  5. Escape and avoidance learning in the earthworm Eisenia hortensis.

    PubMed

    Wilson, W Jeffrey; Ferrara, Nicole C; Blaker, Amanda L; Giddings, Charisa E

    2014-01-01

    Interest in instrumental learning in earthworms dates back to 1912 when Yerkes concluded that they can learn a spatial discrimination in a T-maze. Rosenkoetter and Boice determined in the 1970s that the "learning" that Yerkes observed was probably chemotaxis and not learning at all. We examined a different form of instrumental learning: the ability to learn both to escape and to avoid an aversive stimulus. Freely moving "master" worms could turn off an aversive white light by increasing their movement; the behavior of yoked controls had no effect on the light. We demonstrate that in as few as 12 trials the behavior of the master worms comes under the control of this contingency. PMID:24498578

  6. Escape and avoidance learning in the earthworm Eisenia hortensis

    PubMed Central

    Ferrara, Nicole C.; Blaker, Amanda L.; Giddings, Charisa E.

    2014-01-01

    Interest in instrumental learning in earthworms dates back to 1912 when Yerkes concluded that they can learn a spatial discrimination in a T-maze. Rosenkoetter and Boice determined in the 1970s that the “learning” that Yerkes observed was probably chemotaxis and not learning at all. We examined a different form of instrumental learning: the ability to learn both to escape and to avoid an aversive stimulus. Freely moving “master” worms could turn off an aversive white light by increasing their movement; the behavior of yoked controls had no effect on the light. We demonstrate that in as few as 12 trials the behavior of the master worms comes under the control of this contingency. PMID:24498578

  7. Earthworm

    NSDL National Science Digital Library

    N/A N/A (None; )

    2004-07-06

    Earthworms like to live underground in the moist soil. Two reasons why they are considered to be annelids are because they have a segmented body and they lack true legs. They have soft bodies and as a result don't have any "armor" to protect them. Earthworms can dry up and die after being out of the soil too long or they can easily be eaten by insects, as in the picture.

  8. Relating results from earthworm toxicity tests to agricultural soil

    USGS Publications Warehouse

    Beyer, W.N.

    1992-01-01

    The artificial soil tests of the European Economic Community and of the Organization for Economic Cooperation produce data relating earthworm mortality to pesticide concentrations in soil under laboratory conditions. To apply these results to agricultural soils it is necessary to relate these concentrations to amounts of pesticide applied per area. This paper reviews the relevant published literature and suggests a simple relation for regulatory use. Hazards to earthworms from pesticides are suggested to be greatest soon after application, when the pesticides may be concentrated in a soil layer a few millimeters thick. For estimating exposure of earthworms, however, a thicker soil layer should be considered, to account for their movement through soil. During favorable weather conditions, earthworms belonging to species appropriate to the artificial soil test have been reported to confine their activity to a layer about 5 cm. If a 5-cm layer is accepted as relevant for regulatory purposes, then an application of 1 kg/ha would be equivalent to 1-67 ppm (dry) in the artificial soil test.

  9. Boric acid as alternative reference substance for earthworm field tests

    Microsoft Academic Search

    Petra Stegger; Klaus Peter Ebke; Jörg Römbke

    2011-01-01

    Purpose  Boric acid was applied in an earthworm field test according to ISO 11268-3 as a possible alternative for the currently used\\u000a reference substances that may no longer be available in the near future.\\u000a \\u000a \\u000a \\u000a \\u000a Material and methods  The test site was a pasture with a silt- and clay-dominated soil, a pH of 5.7 and an organic content of 2.8%. In addition\\u000a to

  10. Terrestrial avoidance behaviour tests as screening tool to assess soil contamination

    Microsoft Academic Search

    Susana Loureiro; Amadeu M. V. M. Soares; António J. A. Nogueira

    2005-01-01

    To assess soil quality and risk assessment, bioassays can be useful tools to gauge the potential toxicity of contaminants focusing on their bioavailable fraction. A rapid and sublethal avoidance behaviour test was used as a screening tool with the earthworm Eisenia andrei and the isopod Porcellionides pruinosus, where organisms were exposed during 48h to several chemicals (lindane, dimethoate and copper

  11. Effects of field metal-contaminated soils submitted to phytostabilisation and fly ash-aided phytostabilisation on the avoidance behaviour of the earthworm Eisenia fetida.

    PubMed

    Demuynck, Sylvain; Succiu, Iuliana Rosalia; Grumiaux, Fabien; Douay, Francis; Leprętre, Alain

    2014-09-01

    The earthworm Eisenia fetida avoidance behaviour test was used to assess the quality recovery of metal-contaminated soils from lands submitted for 10 years to remediation. Soils were from plots located in the surroundings of a former lead smelter plant of Northern France. Metal concentrations in the soils ranged from 93 to 1231, 56 to 1424, 0.3 to 20 and 15 to 45.5mg metal/kg dry soil for Pb, Zn, Cd and Cu, respectively. Several former agricultural plots were treated either by a single phytostabilisation process involving the plantation of a tree mix or by fly ash aided-phytostabilisation. Silico-aluminous or sulfo-calcic ashes used were ploughed up to a 25- to 30-cm soil depth at a rate of 23.3kg/m(2) (i.e., 6 percent W/W). E. fetida was shown to avoid significantly the 10 years ash-treated soils whose habitat function has to be considered as limited. This avoidance would relate to a change of the texture of soils induced by the addition of ashes and consisting in an increased level of fine silts together with a decreased level of clays. By contrast, afforested metal-contaminated soils appeared for E. fetida as more attractive than unplanted ones. Regarding the influence of the metal contamination of the soils on E. fetida, none of the soils tested even the highest contaminated one was significantly avoided by worms. This lack of reaction would result from the low bioavailability of the metals in the soils tested. At the lights of our results and those previously published on both these ashes and these ash-treated soils, the usefulness of these soil treatments is discussed. PMID:24949898

  12. Linking litter calcium, earthworms and soil properties: a common garden test with 14 tree

    E-print Network

    Chorover, Jon

    LETTER Linking litter calcium, earthworms and soil properties: a common garden test with 14 tree, and assessed the role of litter chemistry vis-a`-vis such variation. Differences in litter calcium within and among tree groups. Tree species rich in calcium were associated with increased native

  13. EVALUATION OF ALTERNATIVE REFERENCE TOXICANTS FOR USE IN THE EARTHWORM TOXICITY TEST

    EPA Science Inventory

    The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However,the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants...

  14. Earthworm Information

    NSDL National Science Digital Library

    This University of California Sustainable Agriculture Research and Education Program provides several links to articles on earthworms. These describe the earthworm's importance to ecosystems and agriculture.

  15. Acute and chronic toxicity testing of TPH-contaminated soils with the earthworm, Eisenia foetida

    SciTech Connect

    Stewart, A.J.; Wicker, L.F.; Nazerias, M.S. [Oak Ridge National Lab., TN (United States)

    1995-12-31

    Responses of Eisenia foetida to petroleum-contaminated soils are being assessed using a 21-day test described previously. The authors prepared dilutions of two soils, referred to as A and B, using their reference-soil counterparts, collected from near the contaminated sites. The total petroleum hydrocarbon (TPH) content of each soil was measured by latroscan before the dilutions were prepared. References for the A and B soils contained 167 and 1,869 ppm of TPH, respectively. Thus, neither reference soil was pristine. Dilutions of the A soil tested with E. foetida contained from 179 to 305 ppm TPH; dilutions of the B soil contained from 1,875 to 1,950 ppm TPH. E foetida survival was 100% in both dilution series. Mean growth of Eisenia in dilutions of the A soil ranged from 48 to 74 mg dry-weight growth per pair of worms; these values were lower than those in any dilution of the B soil series. Lipid levels of worms in higher concentrations of the A and B soils were similar to one another and to published values, suggesting little inhibition of feeding in either dilution series. Earthworm reproduction was zero in the A series, but moderately high in the B series. Thus, the A soil apparently contained materials other than TPH that inhibited earthworm growth and reproduction. This study shows that (1) TPH at concentrations as high as 1,800 ppm may not always be inhibitor to earthworm growth or reproduction and (2) that earthworm survival, as a test endpoint, is much less sensitive than either growth or reproduction.

  16. Recycled water sources influence the bioavailability of copper to earthworms.

    PubMed

    Kunhikrishnan, Anitha; Bolan, Nanthi S; Naidu, Ravi; Kim, Won-Il

    2013-10-15

    Re-use of wastewaters can overcome shortfalls in irrigation demand and mitigate environmental pollution. However, in an untreated or partially treated state, these water sources can introduce inorganic contaminants, including heavy metals, to soils that are irrigated. In this study, earthworms (Eisenia fetida) have been used to determine copper (Cu) bioavailability in two contrasting soils irrigated with farm dairy, piggery and winery effluents. Soils spiked with varying levels of Cu (0-1,000 mg/kg) were subsequently irrigated with recycled waters and Milli-Q (MQ) water and Cu bioavailability to earthworms determined by mortality and avoidance tests. Earthworms clearly avoided high Cu soils and the effect was more pronounced in the absence than presence of recycled water irrigation. At the highest Cu concentration (1,000 mg/kg), worm mortality was 100% when irrigated with MQ-water; however, when irrigated with recycled waters, mortality decreased by 30%. Accumulation of Cu in earthworms was significantly less in the presence of recycled water and was dependent on CaCl2-extractable free Cu(2+) concentration in the soil. Here, it is evident that organic carbon in recycled waters was effective in decreasing the toxic effects of Cu on earthworms, indicating that the metal-organic complexes decreased Cu bioavailability to earthworms. PMID:23122192

  17. Earthworms as Bioindicators of Soil Quality

    Microsoft Academic Search

    Heinz-Christian Fründ; Ulfert Graefe; Sabine Tischer

    \\u000a Earthworms can indicate soil quality by (1) the abundance and species composition of the earthworm fauna at a particular site,\\u000a (2) the behavior of individual earthworms in contact with a soil substrate (preference\\/avoidance\\/activity), (3) the accumulation\\u000a of chemicals from the soil into the body, and (4) the biochemical\\/cytological stress-biomarkers in the earthworm. Earthworms\\u000a are assessed in several long-term soil monitoring

  18. Evaluation of alternative reference toxicants for use in the earthworm toxicity test

    SciTech Connect

    Yeardley, R.B. Jr. [DynCorp-TAI, Cincinnati, OH (United States); Lazorchak, J.M. [Environmental Protection Agency, Cincinnati, OH (United States); Pence, M.A. [Technology Applications, Inc., Cincinnati, OH (United States)

    1995-07-01

    The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However, the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants was evaluated. Reference toxicants were rated in relation to the following criteria: (a) reproducibility, (b) low human health hazard, (c) feasibility of measurement, and (d) chemical stability. Potassium chloride (KCl) and ammonium chloride (NH{sub 4}Cl) were evaluated as possible alternatives to the one currently in common use, 2-chloroacetamide. Potassium chloride rated the best for the combination of the four criteria, followed by NH{sub 4}Cl and 2-chloroacetamide. Coefficients of variation (C.V.s) from control charts of six definitive tests were use to measure reproducibility. The best reproducibility (lowest C.V.) was shown by KCl, followed by NH{sub 4}Cl and 2-chloroacetamide. Toxicants ranked KCl < NH{sub 4}Cl {much_lt} 2-chloroacetamide in terms of health hazard; and KCl = NH{sub 4}Cl > 2-chloroacetamide in terms of measurement feasibility. Both 2-chloroacetamide and NH{sub 4}Cl changed in concentration during testing. Evidence is also presented that 2-chloroacetamide degrades rapidly during testing, and that, as dead worms decay, ammonification may be adding another toxicant, ammonia, to tests.

  19. Longitudinal in vivo MR imaging of live earthworms.

    PubMed

    Budán, Ferenc; Kovács, Noémi; Engelmann, Péter; Horváth, Ildikó; Veres, Dániel S; Németh, Péter; Szigeti, Krisztián; Máthé, Domokos

    2014-11-01

    Earthworm (Oligochaeta, Lumbricidae) species are used widely in eco-toxicological tests especially with contaminated soils. These long-term tests are reliable, but a high sample size is needed. Magnetic resonance imaging (MRI) can produce fast, robust, sensitive, and longitudinal morphological results using a small sample size. Performing longitudinal in vivo examinations of earthworms using MRI requires the need for anesthetics to completely avoid earthworm's moving. Our goal was to develop a simple and non-invasive method to anesthetize earthworms for in vivo longitudinal imaging studies. We investigated a number of different anesthesia methods and found that propan-2-ol and its vapor was optimal. We used a commercial sequential nanoScan® PET/MRI system (Mediso Ltd, Hungary, Budapest) to explore feasibility of MR imaging in immobilized earthworms. It was possible to visualize via micro MRI the brain, gastrointestinal tract, seminal vesicles, calciferous gland (Morren gland), and main blood vessels of the circulatory system. Our findings show the possibilities to examine changes in morphology using MRI of certain organs using a reversible, long-term immobilization method. PMID:25059556

  20. Comparison of sublethal and lethal criteria for nine different chemicals in standardized toxicity tests using the earthworm Eisenia andrei

    SciTech Connect

    Van Gestel, C.A.; Dirven-Van Breemen, E.M.; Baerselman, R.; Emans, H.J.; Janssen, J.A.; Postuma, R.; Van Vliet, P.J. (National Institute of Public Health and Environmental Protection, Bilthoven, (Netherlands))

    1992-04-01

    In this study, the effects of nine different chemicals on the survival, growth, and reproduction of the earthworm species Eisenia andrei were determined using a recently developed method. Earthworms were exposed for 3 weeks to the test chemicals in an artificial soil substrate. Additional data on the acute toxicity of these chemicals were derived from the literature. For some chemicals, cocoon production was the most sensitive parameter (cadmium, chromium, paraquat, fentin, benomyl, phenmedipham), while for others cocoon hatchability was most sensitive (pentachlorophenol, parathion, carbendazim). In the case of parathion, growth of the worms seemed to be even more sensitive than reproduction. As an overall parameter for the effect on earthworm reproduction, the total number of juveniles produced per worm appeared to be a useful parameter. Differences between (acute) LC50 values and the lowest NOEC value for effects on growth and reproduction were different for each chemical. Difference was greatest for cadmium (a factor of greater than 100) and smallest for fentin, benomyl, and pentachlorophenol (a factor of 5-6).

  1. Herbivory of an invasive slug is affected by earthworms and the composition of plant communities

    PubMed Central

    2013-01-01

    Background Biodiversity loss and species invasions are among the most important human-induced global changes. Moreover, these two processes are interlinked as ecosystem invasibility is considered to increase with decreasing biodiversity. In temperate grasslands, earthworms serve as important ecosystem engineers making up the majority of soil faunal biomass. Herbivore behaviour has been shown to be affected by earthworms, however it is unclear whether these effects differ with the composition of plant communities. To test this we conducted a mesocosm experiment where we added earthworms (Annelida: Lumbricidae) to planted grassland communities with different plant species composition (3 vs. 12 plant spp.). Plant communities had equal plant densities and ratios of the functional groups grasses, non-leguminous forbs and legumes. Later, Arion vulgaris slugs (formerly known as A. lusitanicus; Gastropoda: Arionidae) were added and allowed to freely choose among the available plant species. This slug species is listed among the 100 worst alien species in Europe. We hypothesized that (i) the food choice of slugs would be altered by earthworms’ specific effects on the growth and nutrient content of plant species, (ii) slug herbivory will be less affected by earthworms in plant communities containing more plant species than in those with fewer plant species because of a more readily utilization of plant resources making the impacts of earthworms less pronounced. Results Slug herbivory was significantly affected by both earthworms and plant species composition. Slugs damaged 60% less leaves when earthworms were present, regardless of the species composition of the plant communities. Percent leaf area consumed by slugs was 40% lower in communities containing 12 plant species; in communities containing only three species earthworms increased slug leaf area consumption. Grasses were generally avoided by slugs. Leaf length and number of tillers was increased in mesocosms containing more plant species but little influenced by earthworms. Overall shoot biomass was decreased, root biomass increased in plant communities with more plant species. Earthworms decreased total shoot biomass in mesocosms with more plant species but did not affect biomass production of individual functional groups. Plant nitrogen concentrations across three focus species were 18% higher when earthworms were present; composition of plant communities did not affect plant quality. Conclusions Given the important role that both herbivores and earthworms play in structuring plant communities the implications of belowground-aboveground linkages should more broadly be considered when investigating global change effects on ecosystems. PMID:23668239

  2. Legacy of earthworms' engineering effects enlarges the actual effects of earthworms on plants

    NASA Astrophysics Data System (ADS)

    Mudrák, Obd?ej; Frouz, Jan

    2015-04-01

    Earthworms were recognized as key factor responsible for changes from early to late successional plant communities. They incorporate organic matter into the soil and creates there persistent structures, which improves conditions for plant growth. Earthworm activity might be therefore expected to be more important in early stages of the succession, when earthworm colonization of previously earthworm free soil starts, than in the late stages of the succession, where the soil was previously modified by earthworms. However, earthworms affect plants also via other effects such as increase of nutrient availability. The relative importance of soil structure modification and other earthworm effects on plants is poorly known, despite it is important for both theoretical and applied ecology. To test the effect of earthworms (Lumbricus rubellus and Aporrectodea caliginosa) on plants we performed microcosm laboratory experiment, where earthworms were affecting early successional (Poa compressa, Medicago lupulina, and Daucus carota) and late successional (Arrhenatherum elatius, Lotus corniculatus, and Plantago laceolata) plat species in soil previously unaffected by earthworms and in soil with previous long term effect of earthworms. These soils were taken from the early and late successional monitoring sites of the Sokolov coal mining district with known history. Earthworms increased plant biomass proportionally more in late successional soil. It was mainly because they increased availability of nutrients (nitrate and potassium) and plants get higher advantage out of this in late successional soil. Earthworms increased plant biomass of both early and late successional species, but late successional species suppressed early successional species in competition. This suppression was more intensive in presence of earthworms and in late successional soil. We therefore found multiplicative effect between earthworm soil engineering activity and their other effects, which might be responsible for changes in plant communities during the succession.

  3. Teacher's Guide for Earthworms.

    ERIC Educational Resources Information Center

    Bruno, Merle S.; And Others

    This teacher's guide on earthworms includes four major sections: (1) introduction, (2) caring for earthworms in the classroom, (3) classroom activities, and (4) the appendix. The introduction includes information concerning grade level, scheduling, materials, obtaining earthworms, field study, classroom clean-up, and records. Caring for earthworms

  4. Unexpected earthworm effects on forest understory plants

    PubMed Central

    2013-01-01

    Background Introduced earthworms are widespread in forests of North America creating significant negative impacts on forest understory communities. However, much of the reported evidence for negative earthworm effects comes from field investigations either comparing invaded and non-invaded forests or across invasion fronts. While important, such work is rarely able to capture the true effect of earthworms on individual plant species because most forests in North America simultaneously face multiple stressors which may confound earthworm impacts. We used a mesocosm experiment to isolate effects of the anecic introduced earthworm, Lumbricus terrestris L. on seedlings of 14 native plant species representing different life form groups (perennial herb, graminoid, and tree). Results Earthworm presence did not affect survival, fertility or biomass of any of the seedling plant species tested over a 17-week period. However, L. terrestris presence significantly decreased growth of two sedges (Carex retroflexa Muhl. ex Willd. and Carex radiata (Wahlenb.) Small) by decreasing the number of culms. Conclusions Our mesocosm results with seedlings contrast with field reports indicating extensive and significant negative effects of introduced earthworms on many mature native forbs, and positive effects on sedges. We suggest that earthworm impacts are context- and age-specific and that generalizations about their impacts are potentially misleading without considering and manipulating other associated factors. PMID:24314263

  5. Earthworm in the 21st century

    NASA Astrophysics Data System (ADS)

    Friberg, Paul; Lisowski, Stefan; Dricker, Ilya; Hellman, Sidney

    2010-05-01

    Earthworm (Johnson et al., 1995) is a fully open-source earthquake data acquisition and processing package that is in widespread use through out the world. Earthworm includes basic seismic data acquistion for the majority of the dataloggers currently available and provides network transport mechanisms and common formats as output for data transferral. In addition, it comes with network seismology tools to compute network detections, perform automated arrival picking, and automated hypocentral and magnitude estimations. More importantly it is an open and free framework in the C-programming language that can be used to create new modules that process waveform and earthquake data in near real time. The number of Earthworm installations is growing annually as are the number of contributions to the system. Furthermore its growth into other areas of waveform data acquistion (namely Geomagnetic observatories and Infrasound arrays) show its adaptability to other waveform technologies and processing strategies. In this presentation we discuss the coming challenges to growing Earthworm and new developments in its use; namely the open source add-ons that have become interfaces to Earthworm's core. These add-ons include GlowWorm, MagWorm, Hydra, SWARM, Winston, EarlyBird, Iworm, and most importantly, AQMS (formerly known as CHEETAH). The AQMS, ANSS Quake Monitoring System, is the Earthworm system created in California which has now been installed in the majority of Regional Seismic Networks (RSNs) in the United States. AQMS allows additional real-time and post-processing of Earthworm generated data to be stored and manipulated in a database using numerous database oriented tools. The use of a relational database for persistence provides users with the ability to implement configuration control and research capabilities not available in earlier Earthworm add-ons. By centralizing on AQMS, the RSNs will be able to leverage new developments by easily sharing Earthworm and AQMS modules and avoid the duplication and one-off/custom developments of the past.

  6. COMPARATIVE TOXICITY OF CHEMICALS TO EARTHWORMS

    EPA Science Inventory

    The concentration-response (mortality) relationships of four species of earthworms, Eisentia fetida, Allolobophora tuberculata, Eudrilus eugeniae, and Perionyx excavatus are summarized for 62 chemicals and two test protocols. eibull function is used to summarize these data for ea...

  7. Accumulation of chlorinated benzenes in earthworms

    USGS Publications Warehouse

    Beyer, W.N.

    1996-01-01

    Chlorinated benzenes are widespread in the environment. Hexachlorobenzene, pentachlorobenzene and all isomers of dichlorobenzenes, trichlorobenzenes, and tetrachlorobenzenes, have been detected in fish, water, and sediments from the Great Lakes. This paper describes a long-term (26 week) experiment relating the concentrations of chlorinated benzenes in earthworms to 1) the length of exposure, and it describes three 8-week experiments relating concentrations of chlorinated benzenes in earthworms to 2) their concentration in soil 3) the soil organic matter content and, 4) the degree of chlorination. In the 26-week experiment, the concentration of 1,2,4 - trichlorobenzene in earthworms fluctuated only slightly about a mean of 0.63 ppm (Fig. 1). Although a statistically significant decrease can be demonstrated over the test (Pearson correlation coefficient, r = -0.62 p < 0.05), the decrease was minor. Hexachlorobenzene in earthworms showed a cyclical trend that coincided with replacement of the media, and a slight but statistically significant tendency to increase from about 2 to 3 ppm over the 26 weeks (r = 0.55, p < 0.05). Concentrations of both trichlorobenzene and hexachlorobenzene in earthworms increased as the concentrations in the soil increased (Fig. 2), but leveled off at the highest soil concentrations. The most surprising result of this study was the relatively low concentrations in earthworms compared to those in soils. The average concentration of each of the six isomers of trichlorobenzene and tetrachlorobenzene in earthworms was only about 1 ppm (Table 2); the isomeric structure did not affect accumulation. The concentration of organic matter in soil had a prominent effect on hexachlorobenzene concentrations in earthworms (Fig. 3). Hexachlorobenzene concentrations decreased steadily from 9.3 ppm in earthworms kept in soil without any peat moss added to about 1 ppm in soil containing 16 or 32% organic matter.

  8. Off to the (Earthworm) Races: A Quick and Flexible Lab Experiment for Introductory Zoology Courses.

    ERIC Educational Resources Information Center

    Switzer, Paul V.; Fritz, Ann H.

    2001-01-01

    Presents a hands-on, investigative lab activity for use in an introductory zoology course. Tests the behavioral hypothesis that substrate texture affects earthworm locomotor ability. Provides background information on earthworm locomotion followed by details of the lab exercise. (NB)

  9. Gut wall bacteria of earthworms: a natural selection process

    Microsoft Academic Search

    Dwipendra Thakuria; Olaf Schmidt; Dillon Finan; Damian Egan; Fiona M Doohan

    2010-01-01

    Earthworms and microorganisms are interdependent and their interactions regulate the biogeochemistry of terrestrial soils. Investigating earthworm–microorganism interactions, we tested the hypothesis that differences in burrowing and feeding habits of anecic and endogeic earthworms are reflected by the existence of ecological group-specific gut wall bacterial communities. Bacterial community was detected using automated ribosomal intergenic spacer analysis of 16S and 23S genes

  10. Sequential Probability Ratio Test for Collision Avoidance Maneuver Decisions

    NASA Technical Reports Server (NTRS)

    Carpenter, J. Russell; Markley, F. Landis

    2010-01-01

    When facing a conjunction between space objects, decision makers must chose whether to maneuver for collision avoidance or not. We apply a well-known decision procedure, the sequential probability ratio test, to this problem. We propose two approaches to the problem solution, one based on a frequentist method, and the other on a Bayesian method. The frequentist method does not require any prior knowledge concerning the conjunction, while the Bayesian method assumes knowledge of prior probability densities. Our results show that both methods achieve desired missed detection rates, but the frequentist method's false alarm performance is inferior to the Bayesian method's

  11. Enchytraeus albidus (Enchytraeidae): A test organism in a standardised avoidance test? Effects of different chemical substances

    Microsoft Academic Search

    Mónica J. B. Amorim; Sara Novais; Jörg Römbke; Amadeu M. V. M. Soares

    2008-01-01

    Enchytraeids (Enchytraeus albidus) directly improve the pore structure of the soil and are indirectly involved in regulating the degradation of organic matter. Due to their behavior they are able to avoid unfavorable environmental conditions. Avoidance tests allow a first assessment of toxicity of a contaminated or spiked soil within 48 h, by using the reaction of the enchytraeids as measurement endpoint.

  12. Implementation and testing of a real-time 3-component phase picking program for Earthworm using the CECM algorithm

    NASA Astrophysics Data System (ADS)

    Baker, B. I.; Friberg, P. A.

    2014-12-01

    Modern seismic networks typically deploy three component (3C) sensors, but still fail to utilize all of the information available in the seismograms when performing automated phase picking for real-time event location. In most cases a variation on a short term over long term average threshold detector is used for picking and then an association program is used to assign phase types to the picks. However, the 3C waveforms from an earthquake contain an abundance of information related to the P and S phases in both their polarization and energy partitioning. An approach that has been overlooked and has demonstrated encouraging results is the Component Energy Comparison Method (CECM) by Nagano et al. as published in Geophysics 1989. CECM is well suited to being used in real-time because the calculation is not computationally intensive. Furthermore, the CECM method has fewer tuning variables (3) than traditional pickers in Earthworm such as the Rex Allen algorithm (N=18) or even the Anthony Lomax Filter Picker module (N=5). In addition to computing the CECM detector we study the detector sensitivity by rotating the signal into principle components as well as estimating the P phase onset from a curvature function describing the CECM as opposed to the CECM itself. We present our results implementing this algorithm in a real-time module for Earthworm and show the improved phase picks as compared to the traditional single component pickers using Earthworm.

  13. The influence of time on lead toxicity and bioaccumulation determined by the OECD earthworm toxicity test.

    PubMed

    Davies, Nicola A; Hodson, Mark E; Black, Stuart

    2003-01-01

    Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to investigate these assumptions. The first experiment was a standard toxicity test where lead nitrate was added to a soil in solution to give a range of concentrations. The mortality of the worms and the concentration of lead in the survivors were determined. The LC50s for 14 and 28 days were 5311 and 5395 microgPb g(-1)soil respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 microgPb g(-1)soil. The concentration of lead in the worms was determined at various sampling times. Uptake at both concentrations was linear with time. Worms in the 5000 microg g(-1) soil accumulated lead at a faster rate (3.16 microg Pb g(-1)tissue day(-1)) than those in the 3000 microg g(-1) soil (2.21 microg Pb g(-1)tissue day(-1)). The third experiment was a timed experiment with worms cultivated in soil containing 7000 microgPb g(-1)soil. Soil and lead nitrate solution were mixed and stored at 20 degrees C. Worms were added at various times over a 35-day period. The time to death increased from 23 h, when worms were added directly after the lead was added to the soil, to 67 h when worms were added after the soil had equilibrated with the lead for 35 days. In artificially Pb-amended soils the worms accumulate Pb over the duration of their exposure to the Pb. Thus time limited toxicity tests may be terminated before worm body load has reached a toxic level. This could result in under-estimates of the toxicity of Pb to worms. As the equilibration time of artificially amended Pb-bearing soils increases the bioavailability of Pb decreases. Thus addition of worms shortly after addition of Pb to soils may result in the over-estimate of Pb toxicity to worms. The current OECD acute worm toxicity test fails to take these two phenomena into account thereby reducing the environmental relevance of the contaminant toxicities it is used to calculate. PMID:12475061

  14. ACAT Ground Collision Avoidance Flight Tests Over - Duration: 2 minutes, 41 seconds.

    NASA Video Gallery

    NASA's Dryden Flight Research Center has concluded flight tests of an Automatic Ground Collision Avoidance System (Auto GCAS) under the joint U.S. Air Force/NASA F-16D Automatic Collision Avoidance...

  15. Portable conduction velocity experiments using earthworms for the college and high school neuroscience teaching laboratory

    PubMed Central

    Shannon, Kyle M.; Gage, Gregory J.; Jankovic, Aleksandra; Wilson, W. Jeffrey

    2014-01-01

    The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction velocities that can be easily measured by manipulating electrode placement and the tactile stimulus. Here, we present a portable and robust experimental setup that allows students to perform conduction velocity measurements within a 30-min to 1-h laboratory session. Our improvement over this well-known preparation is the combination of behaviorally relevant tactile stimuli (avoiding electrical stimulation) with the invention of minimal, low-cost, and portable equipment. We tested these experiments during workshops in both a high school and college classroom environment and found positive learning outcomes when we compared pre- and posttests taken by the students. PMID:24585472

  16. Nutrition Studies with Earthworms.

    ERIC Educational Resources Information Center

    Tobaga, Leandro

    1980-01-01

    Describes experiments which demonstrate how different diets affect the growth rate of earthworms. Procedures for feeding baby worms are outlined, the analysis of results are discussed, and various modifications of the exercise are provided. (CS)

  17. Earthworms, as ecosystem engineers, influence multiple aspects of a salamander's ecology.

    PubMed

    Ransom, Tami S

    2011-03-01

    Ecosystem engineers create habitat that can be used by other species in multiple ways, such as refugees from predators, places to breed, or areas with increased prey resources. I conducted a series of enclosure experiments to: (1) determine if salamanders use earthworm burrows, and (2) examine the potential influence of earthworm burrow use and indirect effects on salamander intra- and interspecific competition, predator avoidance, and seasonal performance. I found that one species of woodland salamander, Plethodon cinereus, used earthworm burrows 50% of the time when burrows were present. Neither adults nor juveniles of the congeneric P. glutinosus used earthworm burrows. Intraspecific, but not interspecific, competition by P. cinereus affected salamander behavior when earthworms were absent, with P. cinereus found under cover objects >70% of the time when alone or with a P. glutinosus, but only 40% of the time when with another P. cinereus. When earthworms were present, the behavior of P. cinereus was similar across salamander treatments. Earthworms decreased the amount of leaf litter and microinvertebrates, although this did not affect salamander mass. In subsequent experiments using only P. cinereus, the refuge provided by earthworm burrows increased the survival of P. cinereus over the winter and allowed P. cinereus to avoid being consumed by the common garter snake (Thamnophis sirtalis). Because earthworm burrows provide a refuge for P. cinereus during intraspecific encounters, in the presence of a predator and over the winter, they may serve as an important belowground-aboveground linkage in eastern forests where salamanders are common. PMID:20848134

  18. Effect of earthworms on the biochemical characterization of biofilms in vermifiltration treatment of excess sludge.

    PubMed

    Yang, Jian; Liu, Jing; Xing, Meiyan; Lu, Zhibo; Yan, Qiong

    2013-09-01

    In this study, the biofilms formed in a vermifilter (VF) with earthworms and a conventional biofilter (BF) without earthworms were compared to investigate the effects of earthworms on the characteristics of biofilms during an excess sludge treatment period of 4months. Typical macrographs and micrographs of the biofilms showed that the feeding and casting actions of earthworms remarkably modified the VF morphology. Elemental analysis and fluorescence spectra indicated that earthworms enhanced the stabilization of organic matter by accelerating the mineralization and humification of organic materials during vermiconversion. In addition, bacterial communities inhabiting the VF biofilm showed that earthworms increased both bacterial diversity and metabolic activities in the film, as revealed by automatic testing bacteriology (ATB) expression and sequencing data. These results demonstrate that earthworms influence the structure and biochemical characteristics of biofilms and enhance their bacterial diversity and functions for improved sludge stabilization. PMID:23774291

  19. Native and exotic earthworms affect orchid seed loss

    PubMed Central

    McCormick, Melissa K.; Parker, Kenneth L.; Szlavecz, Katalin; Whigham, Dennis F.

    2013-01-01

    Non-native earthworms have invaded ecosystems around the world but have recently received increased attention as they invaded previously earthworm-free habitats in northern North America. Earthworms can affect plants by ingesting seeds and burying them in the soil. These effects can be negative or positive but are expected to become increasingly negative with decreasing seed size. Orchids have some of the smallest seeds of any plants, so we hypothesized that earthworm consumption of seeds would decrease seed viability and lead to burial of ingested seeds. We used a combination of mesocosms and field measurements to determine whether native and non-native earthworms would affect Goodyera pubescens seed germination by decreasing seed viability through digestion or burial. To determine soil depths at which seed burial would decrease chances of germination, we used field measurements of the abundance of mycorrhizal fungi needed for G. pubescens germination at different soil depths. We found that the combined effects of earthworm ingestion and burial would be expected to result in a loss of 49 % of orchid seeds in mature forests and 68 % of those in successional forests over an average year. Differences in seed ingestion and burial among soils from mature and successional forests were probably driven by differences in their ability to support earthworm biomass and not by differences in earthworm behaviour as a function of soil type. The combined effects of earthworm ingestion and burial have the potential to result in substantial loss of orchid seeds, particularly in successional forests. This effect may slow the ability of orchids to recolonize forests as they proceed through succession. Determining whether this strong effect of earthworms on G. pubescens viability and germination also applies to other orchid species awaits further testing.

  20. Accident Avoidance Skill Training and Performance Testing. Final Report.

    ERIC Educational Resources Information Center

    Hatterick, G. Richard; Barthurst, James R.

    A two-phased study was conducted to determine the feasibility of training drivers to acquire skills needed to avoid critical conflict motor vehicle accidents, and to develop the procedures and materials necessary for such training. Basic data were derived from indepth accident investigations and task analyses of driver behavior. Principal…

  1. DRILLING FLUID CHEMICALS AND EARTHWORM TOXICITY

    Microsoft Academic Search

    Karen McCosh; Jonathan Getliff

    Earthworms can be used to assess toxicity in terrestrial systems and the survival rate of the worms, or changes in other parameters such as biomass, can be used to calculate an LC50 value (lethal concentration to 50% of the population) for test chemicals spiked into soil. This type of information can be useful in predicting the likely toxicological effect of

  2. Computerized Manufacturing Cell An Earthworm and a Leech robot

    E-print Network

    Major, Arkady

    Computerized Manufacturing Cell An Earthworm and a Leech robot Flexible Robot Gripper Professor S modeled after observing the motion of an earthwork and a leech. #12;Aerodynamic testing of a wind turbine

  3. Earthworm immune responses.

    PubMed

    Jarosz, J; Gli?ski, Z

    1997-01-01

    The knowledge of the immunity in annelids started with the use of earthworms as biomarkers indicating changes caused by environmental pollution. Defence strategies effectively protect earthworms against bacterial infections and parasitic invasion. A natural immunity formed by anatomical and chemical protective barriers prevents damage of the underlying tissues, body fluid losses, and microbial infections of the body cavity. The internal defence mechanisms of annelids involve phagocytosis, nodule formation and encapsulation, blood coagulation and wound repair, and antibacterial immune proteins. The antibacterial activity of coelomic fluid associated with lysozyme-like substances and inducible humoral molecules support haemocytic reactions in the annelid defence system. PMID:9557138

  4. Young Men's Aggressive Tactics to Avoid Condom Use: A Test of a Theoretical Model

    ERIC Educational Resources Information Center

    Davis, Kelly Cue; Logan-Greene, Patricia

    2012-01-01

    Although research has demonstrated that men's aggression against women and inconsistent condom use are related phenomena, little is known about what factors increase risk for aggression to avoid condom use. The present article tests a theory-based model of condom avoidance through use of sexual aggression. Adult male participants (N = 289) were…

  5. Measuring and Improving Latency to Avoid Test Suite Wear Out Shin Yoo & Mark Harman

    E-print Network

    Singer, Jeremy

    Measuring and Improving Latency to Avoid Test Suite Wear Out Shin Yoo & Mark Harman King's College London Centre for Research on Evolution, Search & Testing (CREST) London, UK {shin.yoo, mark introduces the concept of test suite latency. The more latent a test suite, the more it is possible

  6. Interaction of plant and earthworm during primary succession in heaps after coal

    NASA Astrophysics Data System (ADS)

    Roubí?ková, Alena; Frouz, Jan

    2015-04-01

    These results of field manipulation experiment show that earthworms can remarkably influence vegetation succession on spoil heaps, namely promoting grasses and late succession species. This is in agreement with concurrent appearance of earthworms and some plant species typical for late-succession communities of meadows and forests aren't purely coincidental. On the other hand, facilitation of soil conditions by plant communities during succession is an important factor in earthworm distribution on the spoil heaps; earthworms showed a low survival on sites with sparse vegetation cover and thin litter layer, which means that their occurrence in certain stages of succession isn't determined only by migration abilities or passive dispersal. More field experiments are needed to test if earthworms could be used in directed succession management practices to speed up the natural rate of succession. Preliminary results from an experiment with introduction earthworms to a 20- year old, earthworm-free site indicate that colonization of this site from a single deposition of about 100 specimen of epigeic and 100 endogeic earthworms is slow and not very efficient. Results show that interaction between earthworm and vegetation are important in ecosystem development in post mining sites.

  7. Toxicological responses of the earthworm Eisenia fetida to 18-crown-6 under laboratory conditions.

    PubMed

    Du, Yongtao; Rao, Pinhua; Li, Yinsheng; Qiu, Jiangping; Qiu, Weiguo; Tang, Hao; Potter, Murray A

    2014-10-01

    The earthworm Eisenia fetida was exposed to artificial soil supplemented with 18-crown-6 (1,4,7,10,13,16-hexaoxacyclooctadecane) to investigate its effects on earthworm mortality, growth, avoidance, burrowing behavior and respiration. The results revealed that 18-crown-6 had the potential to negatively affect the behavior of earthworms. The 7-d LC50 was 585 mg kg(-1) soil. Avoidance behavior was the most sensitive endpoint, with a 48-h EC50 of 120 mg kg(-1) soil. Growth, burrow length and respiration showed general decreases with increasing 18-crown-6 concentrations. Behavioral endpoints and respiration may be regarded as sensitive parameters in evaluating the toxicity of this chemical to earthworms. PMID:25100182

  8. Prey choice by carabid beetles feeding on an earthworm community analysed using species- and lineage-specific PCR primers.

    PubMed

    King, R Andrew; Vaughan, Ian P; Bell, James R; Bohan, David A; Symondson, William O C

    2010-04-01

    The carabid beetle Pterostichus melanarius is a major natural enemy of pests, such as aphids and slugs in agricultural systems. Earthworms are a dominant non-pest component of the diet of P. melanarius which help sustain the beetles during periods when the pest population is low or absent. In this study we wanted to test whether this predator exercises prey choice among different earthworm species or ecological groups. High levels of genetic diversity within morphological species of earthworm necessitated the development of primers that were specific not just to species but lineages and sub-lineages within species as well. Gut samples from beetles were analysed using multiplex-PCR and fluorescent-labelled primers. Calibratory feeding trials were undertaken to calculate median detection times for prey DNA following ingestion. Extensive testing demonstrated that the primers were species-specific, that detection periods were negatively related to amplicon size and that meal size had a highly significant effect on detection periods. Monte Carlo simulations showed that, in general, worms were being predated in proportion to their densities in the field with little evidence of prey choice, other than probable avoidance of the larger, deep-living species. There was no evidence that epigeic species were being taken preferentially in comparison with endogeic species. There was also no evidence that defensive secretions by Allolobophora chlorotica reduced predation pressure on this species by P. melanarius. We concluded that any management system that increases earthworm densities generally, regardless of component species, is likely to be optimal for increasing numbers of this beneficial beetle predator. PMID:20345680

  9. Non-native earthworms promote plant invasion by ingesting seeds and modifying soil properties

    NASA Astrophysics Data System (ADS)

    Clause, Julia; Forey, Estelle; Lortie, Christopher J.; Lambert, Adam M.; Barot, Sébastien

    2015-04-01

    Earthworms can have strong direct effects on plant communities through consumption and digestion of seeds, however it is unclear how earthworms may influence the relative abundance and composition of plant communities invaded by non-native species. In this study, earthworms, seed banks, and the standing vegetation were sampled in a grassland of central California. Our objectives were i) to examine whether the abundances of non-native, invasive earthworm species and non-native grassland plant species are correlated, and ii) to test whether seed ingestion by these worms alters the soil seed bank by evaluating the composition of seeds in casts relative to uningested soil. Sampling locations were selected based on historical land-use practices, including presence or absence of tilling, and revegetation by seed using Phalaris aquatica. Only non-native earthworm species were found, dominated by the invasive European species Aporrectodea trapezoides. Earthworm abundance was significantly higher in the grassland blocks dominated by non-native plant species, and these sites had higher carbon and moisture contents. Earthworm abundance was also positively related to increased emergence of non-native seedlings, but had no effect on that of native seedlings. Plant species richness and total seedling emergence were higher in casts than in uningested soils. This study suggests that there is a potential effect of non-native earthworms in promoting non-native and likely invasive plant species within grasslands, due to seed-plant-earthworm interactions via soil modification or to seed ingestion by earthworms and subsequent cast effects on grassland dynamics. This study supports a growing body of literature for earthworms as ecosystem engineers but highlights the relative importance of considering non-native-native interactions with the associated plant community.

  10. Cooperative Collision Avoidance Step 1 - Technology Demonstration Flight Test Report. Revision 1

    NASA Technical Reports Server (NTRS)

    Trongale, Nicholas A.

    2006-01-01

    The National Aeronautics and Space Administration (NASA) Access 5 Project Office sponsored a cooperative collision avoidance flight demonstration program for unmanned aircraft systems (UAS). This flight test was accomplished between September 21st and September 27th 2005 from the Mojave Airport, Mojave, California. The objective of these flights was to collect data for the Access 5 Cooperative Collision Avoidance (CCA) Work Package simulation effort, i.e., to gather data under select conditions to allow validation of the CCA simulation. Subsequent simulation to be verified were: Demonstrate the ability to detect cooperative traffic and provide situational awareness to the ROA pilot; Demonstrate the ability to track the detected cooperative traffic and provide position information to the ROA pilot; Demonstrate the ability to determine collision potential with detected cooperative traffic and provide notification to the ROA pilot; Demonstrate that the CCA subsystem provides information in sufficient time for the ROA pilot to initiate an evasive maneuver to avoid collision; Demonstrate an evasive maneuver that avoids collision with the threat aircraft; and lastly, Demonstrate the ability to assess the adequacy of the maneuver and determine that the collision potential has been avoided. The Scaled Composites, LLC Proteus Optionally Piloted Vehicle (OPV) was chosen as the test platform. Proteus was manned by two on-board pilots but was also capable of being controlled from an Air Vehicle Control Station (AVCS) located on the ground. For this demonstration, Proteus was equipped with cooperative collision sensors and the required hardware and software to place the data on the downlink. Prior to the flight phase, a detailed set of flight test scenarios were developed to address the flight test objectives. Two cooperative collision avoidance sensors were utilized for detecting aircraft in the evaluation: Traffic Alert and Collision Avoidance System-II (TCAS-II) and Automatic Dependent Surveillance Broadcast (ADS-B). A single intruder aircraft was used during all the flight testing, a NASA Gulfstream III (G-III). During the course of the testing, six geometrically different near-collision scenarios were evaluated. These six scenarios were each tested using various combinations of sensors and collision avoidance software. Of the 54 planned test points 49 were accomplished successfully. Proteus flew a total of 21.5 hours during the testing and the G-III flew 19.8 hours. The testing fully achieved all flight test objectives. The Flight IPT performed an analysis to determine the accuracy of the simulation model used to predict the location of the host aircraft downstream during an avoidance maneuver. The data collected by this flight program was delivered to the Access 5 Cooperative Collision Avoidance (CCA) Work Package Team who was responsible for reporting on their analysis of this flight data.

  11. Simulation and Flight Test Capability for Testing Prototype Sense and Avoid System Elements

    NASA Technical Reports Server (NTRS)

    Howell, Charles T.; Stock, Todd M.; Verstynen, Harry A.; Wehner, Paul J.

    2012-01-01

    NASA Langley Research Center (LaRC) and The MITRE Corporation (MITRE) have developed, and successfully demonstrated, an integrated simulation-to-flight capability for evaluating sense and avoid (SAA) system elements. This integrated capability consists of a MITRE developed fast-time computer simulation for evaluating SAA algorithms, and a NASA LaRC surrogate unmanned aircraft system (UAS) equipped to support hardware and software in-the-loop evaluation of SAA system elements (e.g., algorithms, sensors, architecture, communications, autonomous systems), concepts, and procedures. The fast-time computer simulation subjects algorithms to simulated flight encounters/ conditions and generates a fitness report that records strengths, weaknesses, and overall performance. Reviewed algorithms (and their fitness report) are then transferred to NASA LaRC where additional (joint) airworthiness evaluations are performed on the candidate SAA system-element configurations, concepts, and/or procedures of interest; software and hardware components are integrated into the Surrogate UAS research systems; and flight safety and mission planning activities are completed. Onboard the Surrogate UAS, candidate SAA system element configurations, concepts, and/or procedures are subjected to flight evaluations and in-flight performance is monitored. The Surrogate UAS, which can be controlled remotely via generic Ground Station uplink or automatically via onboard systems, operates with a NASA Safety Pilot/Pilot in Command onboard to permit safe operations in mixed airspace with manned aircraft. An end-to-end demonstration of a typical application of the capability was performed in non-exclusionary airspace in October 2011; additional research, development, flight testing, and evaluation efforts using this integrated capability are planned throughout fiscal year 2012 and 2013.

  12. Optimizing Earthworm Sampling in Ecosystems

    Microsoft Academic Search

    Jan Valckx; Gerard Govers; Martin Hermy; Bart Muys

    \\u000a To quantify the role of earthworms in ecosystems, a precise and accurate estimation of their diversity, abundance and biomass\\u000a is needed. In this chapter, we contribute to the optimization of earthworm sampling in terms of (1) how to sample, (2) where\\u000a to sample and (3) how many samples to take. First, we assess optimal concentrations of chemical expellants (allyl isothiocyanate

  13. Earthworm invasion into previously earthworm-free temperate and boreal forests

    Microsoft Academic Search

    Lee E. Frelich; Cindy M. Hale; Stefan Scheu; Andrew R. Holdsworth; Liam Heneghan; Patrick J. Bohlen; Peter B. Reich

    2006-01-01

    Earthworms are keystone detritivores that can influence primary producers by changing seedbed conditions, soil characteristics, flow of water, nutrients and carbon, and plant–herbivore interactions. The invasion of European earthworms into previously earthworm-free temperate and boreal forests of North America dominated by Acer, Quercus, Betula, Pinus and Populus has provided ample opportunity to observe how earthworms engineer ecosystems. Impacts vary with

  14. Use of plant and earthworm bioassays to evaluate remediation of soil from a site contaminated with polychlorinated biphenyls

    Microsoft Academic Search

    John R. Meier; Lina W. Chang; M. C. Meckes; M. K. Smith; S. Jacobs; J. Torsella

    1997-01-01

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The earthworm toxicity bioassays were the 14-d survival test and 21-d reproduction test, using Lumbricus terrestris and Eisenia fetida andrei.

  15. Small UAV Automatic Ground Collision Avoidance System Design Considerations and Flight Test Results

    NASA Technical Reports Server (NTRS)

    Sorokowski, Paul; Skoog, Mark; Burrows, Scott; Thomas, SaraKatie

    2015-01-01

    The National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center Small Unmanned Aerial Vehicle (SUAV) Automatic Ground Collision Avoidance System (Auto GCAS) project demonstrated several important collision avoidance technologies. First, the SUAV Auto GCAS design included capabilities to take advantage of terrain avoidance maneuvers flying turns to either side as well as straight over terrain. Second, the design also included innovative digital elevation model (DEM) scanning methods. The combination of multi-trajectory options and new scanning methods demonstrated the ability to reduce the nuisance potential of the SUAV while maintaining robust terrain avoidance. Third, the Auto GCAS algorithms were hosted on the processor inside a smartphone, providing a lightweight hardware configuration for use in either the ground control station or on board the test aircraft. Finally, compression of DEM data for the entire Earth and successful hosting of that data on the smartphone was demonstrated. The SUAV Auto GCAS project demonstrated that together these methods and technologies have the potential to dramatically reduce the number of controlled flight into terrain mishaps across a wide range of aviation platforms with similar capabilities including UAVs, general aviation aircraft, helicopters, and model aircraft.

  16. Earthworms Use Odor Cues to Locate and Feed on Microorganisms in Soil

    PubMed Central

    Zirbes, Lara; Mescher, Mark; Vrancken, Véronique; Wathelet, Jean-Paul; Verheggen, François J.; Thonart, Philippe; Haubruge, Eric

    2011-01-01

    Earthworms are key components of temperate soil ecosystems but key aspects of their ecology remain unexamined. Here we elucidate the role of olfactory cues in earthworm attraction to food sources and document specific chemical cues that attract Eisenia fetida to the soil fungi Geotrichum candidum. Fungi and other microorganisms are major sources of volatile emissions in soil ecosystems as well as primary food sources for earthworms, suggesting the likelihood that earthworms might profitably use olfactory cues to guide foraging behavior. Moreover, previous studies have documented earthworm movement toward microbial food sources. But, the specific olfactory cues responsible for earthworm attraction have not previously been identified. Using olfactometer assays combined with chemical analyses (GC-MS), we documented the attraction of E. fetida individuals to filtrate derived from G. candidum colonies and to two individual compounds tested in isolation: ethyl pentanoate and ethyl hexanoate. Attraction at a distance was observed when barriers prevented the worms from reaching the target stimuli, confirming the role of volatile cues. These findings enhance our understanding of the mechanisms underlying key trophic interactions in soil ecosystems and have potential implications for the extraction and collection of earthworms in vermiculture and other applied activities. PMID:21799756

  17. Earthworms drive succession of both plant and Collembola communities in post-mining sites

    NASA Astrophysics Data System (ADS)

    Mudrák, Obd?ej; Frouz, Jan

    2015-04-01

    Previous field observations indicated that earthworms promote late-successional plant species and reduce collembolan numbers at post-mining sites in the Sokolov coal mining district (Czech Republic). Here, we established a laboratory pot experiment to test the effect of earthworms (Aporrectodea caliginosa Savigny and Lumbricus rubellus Hoffm.) and litter of low, medium, and high quality (the grass Calamagrostis epigejos, the willow Salix caprea, and the alder Alnus glutinosa, respectively) on late successional plants (grasses Arrhenatherum elatius and Agrostis capillaris, legumes Lotus corniculatus and Trifolium medium, and non-leguminous dicots Centaurea jacea and Plantago lanceolata) in spoil substrate originating from Sokolov post-mining sites and naturally inhabited by abundant numbers of Collembola. The earthworms increased plant biomass, especially that of the large-seeded A. elatius, but reduced the number of plant individuals, mainly that of the small-seeded A. capillaris and both legumes. Litter quality affected plant biomass, which was highest with S. caprea litter, but did not change the number of plant individuals. Litter quality did not modify the effect of earthworms on plants; the effect of litter quality and earthworms was only additive. Species composition of Collembola community was altered by litter quality, but earthworms reduced the number of individuals, increased the number of species, and increased species evenness consistently across the litter qualities. Because the results of this experiment were consistent with the field observations, we conclude that earthworms help drive succession of both plant and Collembola communities on post-mining sites.

  18. Warming shifts `worming': effects of experimental warming on invasive earthworms in northern North America

    NASA Astrophysics Data System (ADS)

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.

    2014-11-01

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.

  19. Automated Analysis of Two-Dimensional Positions and Body Lengths of Earthworms (Oligochaeta); MimizuTrack

    PubMed Central

    Yonemura, Seiichiro; Kaneda, Satoshi; Ohashi, Mizue; Ikeno, Hidetoshi

    2014-01-01

    Earthworms are important soil macrofauna inhabiting almost all ecosystems. Their biomass is large and their burrowing and ingestion of soils alters soil physicochemical properties. Because of their large biomass, earthworms are regarded as an indicator of “soil heath”. However, primarily because the difficulties in quantifying their behavior, the extent of their impact on soil material flow dynamics and soil health is poorly understood. Image data, with the aid of image processing tools, are a powerful tool in quantifying the movements of objects. Image data sets are often very large and time-consuming to analyze, especially when continuously recorded and manually processed. We aimed to develop a system to quantify earthworm movement from video recordings. Our newly developed program successfully tracked the two-dimensional positions of three separate parts of the earthworm and simultaneously output the change in its body length. From the output data, we calculated the velocity of the earthworm's movement. Our program processed the image data three times faster than the manual tracking system. To date, there are no existing systems to quantify earthworm activity from continuously recorded image data. The system developed in this study will reduce input time by a factor of three compared with manual data entry and will reduce errors involved in quantifying large data sets. Furthermore, it will provide more reliable measured values, although the program is still a prototype that needs further testing and improvement. Combined with other techniques, such as measuring metabolic gas emissions from earthworm bodies, this program could provide continuous observations of earthworm behavior in response to environmental variables under laboratory conditions. In the future, this standardized method will be applied to other animals, and the quantified earthworm movement will be incorporated into models of soil material flow dynamics or behavior in response to chemical substances present in the soil. PMID:24886977

  20. Flight test of a low-altitude helicopter guidance system with obstacle avoidance capability

    NASA Technical Reports Server (NTRS)

    Zelenka, Richard E.; Clark, Raymond F.; Branigan, Robert G.

    1995-01-01

    Military aircraft regularly conduct missions that include low-atltitude, near-terrain flight in order to increase covertness and payload effectiveness. Civilian applications include airborne fire fighting, police surveillance, search and rescue, and helicopter emergency medical service. Several fixed-wing aircraft now employ terrain elevation maps and forward-pointed radars to achieve automated terrain following or terrain avoidance flight. Similar systems specialized to helicopters and their flight regime have not received as much attention. A helicopter guidance system relying on digitized terrain elevation maps has been developed that employs airborne navigation, mission requirements, aircraft performance limits, and radar altimeter returns to generate a valley-seeking, low-altitude trajectory between waypoints. The guidance trajectory is symbolically presented to the pilot on a helmet mounted display. This system has been flight tested to 150 ft (45.7 m) above ground level altitude at 80 kts, and is primarily limited by the ability of the pilot to perform manual detection and avoidance of unmapped hazards. In this study, a wide field of view laser radar sensor has been incorporated into this guidance system to assist the pilot in obstacle detection and avoidance, while expanding the system's operational flight envelope. The results from early flight tests of this system are presented. Low-altitude missions to 100 ft (30.5 m) altitude at 80n kts in the presence of unmapped natural and man-made obstacles were demonstrated while the pilot maintained situational awareness and tracking of the guidance trajectory. Further reductions in altitude are expected with continued flight testing.

  1. Earthworm invasion into previously earthworm-free temperate and boreal forests

    Microsoft Academic Search

    Lee E. Frelich; Cindy M. Hale; Peter B. Reich; Andrew R. Holdsworth; Stefan Scheu; Liam Heneghan; Patrick J. Bohlen

    Earthworms are keystone detritivores that can influence primary producers by changing seedbed conditions, soil characteristics,\\u000a flow of water, nutrients and carbon, and plant-herbivore interactions. The invasion of European earthworms into previously\\u000a earthworm-free temperate and boreal forests of North America dominated by Acer, Quercus, Betula, Pinus and Populus has provided ample opportunity to observe how earthworms engineer ecosystems. Impacts vary with

  2. Protein Hydrolysates Are Avoided by Herbivores but Not by Omnivores in Two-Choice Preference Tests

    PubMed Central

    Field, Kristin L.; Bachmanov, Alexander A.; Mennella, Julie A.; Beauchamp, Gary K.; Kimball, Bruce A.

    2009-01-01

    Background The negative sensory properties of casein hydrolysates (HC) often limit their usage in products intended for human consumption, despite HC being nutritious and having many functional benefits. Recent, but taxonomically limited, evidence suggests that other animals also avoid consuming HC when alternatives exist. Methodology/Principal Findings We evaluated ingestive responses of five herbivorous species (guinea pig, mountain beaver, gopher, vole, and rabbit) and five omnivorous species (rat, coyote, house mouse, white-footed mouse, and deer mouse; N?=?16–18/species) using solid foods containing 20% HC in a series of two-choice preference tests that used a non-protein, cellulose-based alternative. Individuals were also tested with collagen hydrolysate (gelatin; GE) to determine whether it would induce similar ingestive responses to those induced by HC. Despite HC and GE having very different nutritional and sensory qualities, both hydrolysates produced similar preference score patterns. We found that the herbivores generally avoided the hydrolysates while the omnivores consumed them at similar levels to the cellulose diet or, more rarely, preferred them (HC by the white-footed mouse; GE by the rat). Follow-up preference tests pairing HC and the nutritionally equivalent intact casein (C) were performed on the three mouse species and the guinea pigs. For the mice, mean HC preference scores were lower in the HC v C compared to the HC v Cel tests, indicating that HC's sensory qualities negatively affected its consumption. However, responses were species-specific. For the guinea pigs, repeated exposure to HC or C (4.7-h sessions; N?=?10) were found to increase subsequent HC preference scores in an HC v C preference test, which was interpreted in the light of conservative foraging strategies thought to typify herbivores. Conclusions/Significance This is the first empirical study of dietary niche-related taxonomic differences in ingestive responses to protein hydrolysates using multiple species under comparable conditions. Our results provide a basis for future work in sensory, physiological, and behavioral mechanisms of hydrolysate avoidance and on the potential use of hydrolysates for pest management. PMID:19122811

  3. Earthworm invasions of ecosystems devoid of earthworms: effects on soil microbes

    Microsoft Academic Search

    M. A. McLean; S. Migge-Kleian; D. Parkinson

    2006-01-01

    Recent studies document North American earthworm invasions and their profound effects on the structure of the soil profile, which is the habitat for soil microorganisms (mainly fungi and bacteria). Dramatic alterations made to these layers during earthworm invasion significantly change microbial community structure and therefore microbial activities such as C transformations. Understanding the impacts of earthworm invasion on the microbes

  4. Earthworm in the 21st century

    Microsoft Academic Search

    Paul Friberg; Stefan Lisowski; Ilya Dricker; Sidney Hellman

    2010-01-01

    Earthworm (Johnson et al., 1995) is a fully open-source earthquake data acquisition and processing package that is in widespread use through out the world. Earthworm includes basic seismic data acquistion for the majority of the dataloggers currently available and provides network transport mechanisms and common formats as output for data transferral. In addition, it comes with network seismology tools to

  5. Development and Testing of a Vehicle Collision Avoidance System Based on GPS and Wireless Networks for Open-Pit Mines

    Microsoft Academic Search

    ANTONIO NIETO; KADRI DAGDELEN

    A vehicle proximity warning - collision avoidance system is being developed using GPS and wireless local area networks to improve safety of off-highway trucks in open pit mines. After two an a half years of research, software development, and laboratory testing, field tests were carried out at operating limestone quarries and open pit mining operations to evaluate GPS accuracy and

  6. Avoidant romantic attachment and female orgasm: testing an emotion-regulation hypothesis

    Microsoft Academic Search

    Danielle L. Cohen; Jay Belsky

    2008-01-01

    Recent research indicating that roughly a third of the variation in female orgasmic frequency is heritable leaves a substantial amount of non-heritable variation to be explained. Given that emotion regulation is central to attachment theory and that attachment insecurity in infancy and avoidance in adulthood are not heritable, it was predicted that (higher levels of) avoidance would predict (lower levels

  7. COMPARISON OF THREE EARTHWORM BIOASSAY PROCEDURES FOR THE ASSESSMENT OF ENVIRONMENTAL SAMPLES CONTAINING HAZARDOUS WASTES

    EPA Science Inventory

    Three different laboratory earthworm protocols for assessing the potential toxicity of environmental samples were evaluated using Eisenia fetida. The 48-h Contact Test (CT) is a short test and may indicate the presence of water-soluble chemicals. The 14-day Soil Test (ST) is best...

  8. Testing the role of reward and punishment sensitivity in avoidance behavior: a computational modeling approach.

    PubMed

    Sheynin, Jony; Moustafa, Ahmed A; Beck, Kevin D; Servatius, Richard J; Myers, Catherine E

    2015-04-15

    Exaggerated avoidance behavior is a predominant symptom in all anxiety disorders and its degree often parallels the development and persistence of these conditions. Both human and non-human animal studies suggest that individual differences as well as various contextual cues may impact avoidance behavior. Specifically, we have recently shown that female sex and inhibited temperament, two anxiety vulnerability factors, are associated with greater duration and rate of the avoidance behavior, as demonstrated on a computer-based task closely related to common rodent avoidance paradigms. We have also demonstrated that avoidance is attenuated by the administration of explicit visual signals during "non-threat" periods (i.e., safety signals). Here, we use a reinforcement-learning network model to investigate the underlying mechanisms of these empirical findings, with a special focus on distinct reward and punishment sensitivities. Model simulations suggest that sex and inhibited temperament are associated with specific aspects of these sensitivities. Specifically, differences in relative sensitivity to reward and punishment might underlie the longer avoidance duration demonstrated by females, whereas higher sensitivity to punishment might underlie the higher avoidance rate demonstrated by inhibited individuals. Simulations also suggest that safety signals attenuate avoidance behavior by strengthening the competing approach response. Lastly, several predictions generated by the model suggest that extinction-based cognitive-behavioral therapies might benefit from the use of safety signals, especially if given to individuals with high reward sensitivity and during longer safe periods. Overall, this study is the first to suggest cognitive mechanisms underlying the greater avoidance behavior observed in healthy individuals with different anxiety vulnerabilities. PMID:25639540

  9. Earthworm invasions of ecosystems devoid of earthworms: effects on soil microbes

    Microsoft Academic Search

    M. A. McLean; S. Migge-Kleian; D. Parkinson

    Recent studies document North American earthworm invasions and their profound effects on the structure of the soil profile,\\u000a which is the habitat for soil microorganisms (mainly fungi and bacteria). Dramatic alterations made to these layers during\\u000a earthworm invasion significantly change microbial community structure and therefore microbial activities such as C transformations.\\u000a Understanding the impacts of earthworm invasion on the microbes

  10. Biotic interactions modify the transfer of cesium-137 in a soil-earthworm-plant-snail food web.

    PubMed

    Fritsch, Clémentine; Scheifler, Renaud; Beaugelin-Seiller, Karine; Hubert, Philippe; Coeurdassier, Michaël; de Vaufleury, Annette; Badot, Pierre-Marie

    2008-08-01

    The present study investigated the possible influence of the earthworm Aporrectodea tuberculata on the transfer of cesium-137 ((137)Cs) from a contaminated (130 Bq/kg) deciduous forest soil to the lettuce Lactuca sativa and to the snail Cantareus aspersus (formerly Helix aspersa) in two laboratory experiments. In the first experiment, the International Organization for Standardization 15952 test was used to expose snails for five weeks to contaminated soil with or without earthworms. In these conditions, the presence of earthworms caused a two- to threefold increase in (137)Cs concentrations in snails. Transfer was low in earthworms as well as in snails, with transfer factors (TFs) lower than 3.7 x 10(-2). Activity concentrations were higher in earthworms (2.8- 4.8 Bq/kg dry mass) than in snails (<1.5 Bq/kg). In the second experiment, microcosms were used to determine the contribution of soil and lettuce in the accumulation of (137)Cs in snails. Results suggest that the contribution of lettuce and soil is 80 and 20%, respectively. Microcosms also were used to study the influence of earthworms on (137)Cs accumulation in snail tissues in the most ecologically relevant treatment (soil-earthworm-plant-snail food web). In this case, soil-to-plant transfer was high, with a TF of 0.8, and was not significantly modified by earthworms. Conversely, soil-to-snail transfer was lower (TF, approximately 0.1) but was significantly increased in presence of earthworms. Dose rates were determined in the microcosm study with the EDEN (elementary dose evaluation for natural environment) model. Dose rates were lower than 5.5 x 10(-4) mGy/d, far from values considered to have effects on terrestrial organisms (1 mGy/d). PMID:18266477

  11. CHANGES IN HARDWOOD FOREST UNDERSTORY PLANT COMMUNITIES IN RESPONSE TO EUROPEAN EARTHWORM INVASIONS

    Microsoft Academic Search

    Cindy M. Hale; Lee E. Frelich; Peter B. Reich

    2006-01-01

    European earthworms are colonizing earthworm-free northern hardwood forests across North America. Leading edges of earthworm invasion provide an opportunity to investigate the response of understory plant communities to earthworm invasion and whether the species composition of the earthworm community influences that response. Four sugar maple-dominated forest sites with active earthworm invasions were identified in the Chippewa National Forest in north

  12. Partial order techniques for vehicle collision avoidance: application to an autonomous roundabout test-bed

    E-print Network

    Desaraju, Vishnu Rajeswar

    In this paper, we employ partial order techniques to develop linear complexity algorithms for guaranteed collision avoidance between vehicles at highway and roundabout mergings. These techniques can be employed by virtue ...

  13. Plant genetic variation mediates an indirect ecological effect between belowground earthworms and aboveground aphids

    PubMed Central

    2014-01-01

    Background Interactions between aboveground and belowground terrestrial communities are often mediated by plants, with soil organisms interacting via the roots and aboveground organisms via the shoots and leaves. Many studies now show that plant genetics can drive changes in the structure of both above and belowground communities; however, the role of plant genetic variation in mediating aboveground-belowground interactions is still unclear. We used an earthworm-plant-aphid model system with two aphid species (Aphis fabae and Acyrthosiphon pisum) to test the effect of host-plant (Vicia faba) genetic variation on the indirect interaction between the belowground earthworms (Eisenia veneta) on the aboveground aphid populations. Results Our data shows that host-plant variety mediated an indirect ecological effect of earthworms on generalist black bean aphids (A. fabae), with earthworms increasing aphid growth rate in three plant varieties but decreasing it in another variety. We found no effect of earthworms on the second aphid species, the pea aphid (A. pisum), and no effect of competition between the aphid species. Plant biomass was increased when earthworms were present, and decreased when A. pisum was feeding on the plant (mediated by plant variety). Although A. fabae aphids were influenced by the plants and worms, they did not, in turn, alter plant biomass. Conclusions Previous work has shown inconsistent effects of earthworms on aphids, but we suggest these differences could be explained by plant genetic variation and variation among aphid species. This study demonstrates that the outcome of belowground-aboveground interactions can be mediated by genetic variation in the host-plant, but depends on the identity of the species involved. PMID:25331082

  14. 1 H NMR and GC\\/MS metabolomics of earthworm responses to sub-lethal DDT and endosulfan exposure

    Microsoft Academic Search

    Jennifer R. McKelvie; Jimmy Yuk; Yunping Xu; Andre J. Simpson; Myrna J. Simpson

    2009-01-01

    The metabolic response of the earthworm Eisenia fetida to two pesticides, dichlorodiphenyltrichloroethane (DDT) and endosulfan, was characterized in contact tests using proton\\u000a nuclear magnetic resonance (1H NMR) and principal component analysis (PCA). PCA loading plots suggested that maltose, leucine and alanine were important\\u000a metabolites contributing to the differences in dosed and control earthworms for both compounds at doses of 0.5,

  15. Effect of earthworm on growth of late succession plant species in postmining sites under laboratory and field conditions

    Microsoft Academic Search

    Alena Roubí?ková; Ond?ej Mudrák; Jan Frouz

    2009-01-01

    Earlier studies of postmining heaps near Sokolov, Czech Republic (0–46 years old) showed that massive changes in plant community\\u000a composition occur around 23 year of succession when the heaps are colonized by the earthworms Lumbricus rubellus (Hoffm.) and Aporrectodea caliginosa (Savigny). The aim of the current study was to test the hypothesis that the introduction of earthworms into a postmining\\u000a soil enhances

  16. Pyrosequencing of prey DNA in reptile faeces: analysis of earthworm consumption by slow worms.

    PubMed

    Brown, David S; Jarman, Simon N; Symondson, William O C

    2012-03-01

    Little quantitative ecological information exists on the diets of most invertebrate feeding reptiles, particularly nocturnal or elusive species that are difficult to observe. In the UK and elsewhere, reptiles are legally required to be relocated before land development can proceed, but without knowledge of their dietary requirements, the suitability of receptor sites cannot be known. Here, we tested the ability of non-invasive DNA-based molecular diagnostics (454 pyrosequencing) to analyse reptile diets, with the specific aims of determining which earthworm species are exploited by slow worms (the legless lizard Anguis fragilis) and whether they feed on the deeper-living earthworm species that only come to the surface at night. Slow worm faecal samples from four different habitats were analysed using earthworm-specific PCR primers. We found that 86% of slow worms (N=80) had eaten earthworms. In lowland heath and marshy/acid grassland, Lumbricus rubellus, a surface-dwelling epigeic species, dominated slow worm diet. In two other habitats, riverside pasture and calciferous coarse grassland, diet was dominated by deeper-living anecic and endogeic species. We conclude that all species of earthworm are exploited by these reptiles and lack of specialization allows slow worms to thrive in a wide variety of habitats. Pyrosequencing of prey DNA in faeces showed promise as a practical, rapid and relatively inexpensive means of obtaining detailed and valuable ecological information on the diets of reptiles. PMID:22176947

  17. Biochemical diversity of betaines in earthworms

    SciTech Connect

    Liebeke, Manuel [Department of Surgery and Cancer, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom)] [Department of Surgery and Cancer, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom); Bundy, Jacob G., E-mail: j.bundy@imperial.ac.uk [Department of Surgery and Cancer, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom)

    2013-01-25

    Highlights: ? We develop a method for rapid untargetted analysis of betaines. ? We profile betaines in a comparative study of ten earthworm species. ? Earthworms contain a surprisingly high number of different betaine metabolites. ? Earthworms contain betaines normally seen only in plants or marine animals. -- Abstract: The ability to accumulate osmoprotectant compounds, such as betaines, is an important evolutionary feature in many organisms. This is particularly the case for organisms that live in variable environments, which may have fluctuations in moisture and salinity levels. There is, surprisingly, very little known about betaines in soil invertebrates in general, and there is almost no information about earthworms – a group that are important ‘ecosystem engineers’ and key indicators of soil health. Here, we describe a fast and reliable {sup 1}H–{sup 13}C heteronuclear single quantum coherence (HSQC) 2D NMR approach for the metabolic profiling of a series of betaines and related metabolites in tissue extracts, and list {sup 1}H and {sup 13}C chemical shifts for the trimethylammonium signal for 23 such compounds. The analysis of ten different species from three different families (Lumbricidae, Megascolecidae and Glossoscolecidae) showed an unexpected diversity of betaines present in earthworms. In total ten betaines were identified, including hydroxyproline-betaine, proline-betaine, taurine-betaine, GABA-betaine and histidine-betaine, and a further eleven as-yet unassigned putative betaine metabolites detected. The findings clearly indicate a hitherto-unappreciated important role for betaine metabolism in earthworms.

  18. Improving ecological risk assessment in the Mediterranean area: selection of reference soils and evaluating the influence of soil properties on avoidance and reproduction of two oligochaete species.

    PubMed

    Chelinho, Sónia; Domene, Xavier; Campana, Paolo; Natal-da-Luz, Tiago; Scheffczyk, Adam; Römbke, Jörg; Andrés, Pilar; Sousa, José Paulo

    2011-05-01

    A current challenge in soil ecotoxicology is the use of natural soils as test substrates to increase ecological relevance of data. Despite the existence of six natural reference soils (the Euro-soils), some parallel projects showed that these soils do not accurately represent the diversity of European soils. Particularly, Mediterranean soils are not properly represented. To fill this gap, 12 natural soils from the Mediterranean regions of Alentejo, Portugal; Cataluńa, Spain; and Liguria, Italy, were selected and used in reproduction and avoidance tests to evaluate the soil habitat function for earthworms (Eisenia andrei) and enchytraeids (Enchytraeus crypticus). Predictive models on the influence of soil properties on the responses of these organisms were developed using generalized linear models. Results indicate that the selected soils can impact reproduction and avoidance behavior of both Oligochaete species. Reproduction of enchytraeids was affected by different soil properties, but the test validity criteria were fulfilled. The avoidance response of enchytraeids was highly variable, but significant effects of texture and pH were found. Earthworms were more sensitive to soil properties. They did not reproduce successfully in three of the 10 soils, and a positive influence of moisture, fine sand, pH, and organic matter and a negative influence of clay were found. Moreover, they strongly avoided soils with extreme textures. Despite these limitations, most of the selected soils are suitable substrates for ecotoxicological evaluations. PMID:21305581

  19. Acephaline gregarine parasites (Monocystis sp.) are not transmitted sexually among their lumbricid earthworm hosts.

    PubMed

    Field, Stuart G; Michiels, Nico K

    2006-04-01

    The precise transmission mode(s) of acephaline gregarines in their earthworm hosts has long been questioned, yet a rigorous experimental evaluation of sexual transmission is currently lacking. That Monocystis sp., a common gregarine parasite of the earthworm Lumbricus terrestris, infects the sexual organs of its host is suggestive of sexual transmission. Considering the divergent evolutionary consequences of various modes of transmission, excluding or proving sexual transmission in this host-parasite system is critical to fully understanding it. We cultured uninfected earthworms from cocoons and subsequently mated them to either an infected or uninfected partner (from the wild). We then compared these individuals with an orally infected group, which were infected using a newly developed gavage (oral injection) method. Our data have unambiguously established that (1) horizontal sexual transmission does not play a significant role in the transmission of Monocystis sp., and (2) oral transmission through the soil is likely the principal mode of transmission between earthworms. This finding is important to models of mate-choice because infection avoidance does not appear to drive mating decisions. Finally, we further report a successful and relatively simple method to obtain infection-free individuals, which can subsequently be infected via oral gavage and used in empirical studies. PMID:16729685

  20. The second wave of earthworm invasion: soil organic matter dynamics from the stable isotope perspective

    NASA Astrophysics Data System (ADS)

    Chang, C.; Szlavecz, K. A.; Bernard, M.; Pitz, S.

    2013-12-01

    Through transformation of plant litter into soil organic matter (SOM) and translocation of ingested organic material among different soil depths, soil organisms, especially earthworms, are one of the major factors affecting SOM dynamics. In North America temperate soil, historical human activity has lead to invasion of European earthworms into habitats that were previously earthworm-free or inhabited only by native species. By consuming leaf litter and SOM, burrowing, and casting, invasive earthworms have been known for reducing the understory vegetation and leaf litter layer while increasing the thickness of organic soil, causing changes in the soil habitat and the distribution of SOM. Recently, another group of invasive earthworm, namely Amynthas from Asia, has been reported invading habitats already dominated by European species, causing a 'second wave of invasion' where the soil ecosystem, already modified by European species, is going through another transition. The mechanisms through which these functionally (ecologically) different species affect C and N transformation could be better understood by tracing the carbon and nitrogen derived from 13C- and 15N-labeled leaf litter into earthworm tissues and SOM. The objective of this study is to understand how earthworm species that differ ecologically, including the Asian Amynthas, interact with each other and how these interactions affect SOM dynamics. We hypothesized that 1) species feeding on different food resources will have different isotopic signature and their tissue 13C and 15N values will change due to facilitation or interspecific competition on food resources, and 2) the short-term fate of litter-derived carbon differs depending on the presence or absence of different earthworm species. These hypotheses were tested by field sampling and lab mesocosm experiments using 13C and 15N double-enriched Tulip Poplar leaf litter (mean 13C = 124‰, mean 15N = 1667‰) produced from tree saplings growing in an airtight chamber. Stable isotope mass balance calculation is used to estimate the recovery of litter-derived carbon from three pools (earthworm tissue, SOM, remaining litter), the loss of litter-derived carbon through soil respiration, and the contribution of different carbon sources to soil CO2 efflux in different earthworm treatments. Our results show that earthworm species recognized as 'soil feeders' have 13C and 15N values that are 1.2‰ and 3.8‰ higher than those of 'litter feeders', and 15N also differ significantly amount different soil feeders, suggesting different food resource usage even within the same functional group. There are strong species effects on both leaf litter disappearance rate and CO2 efflux rate, both being high when Amynthas earthworms are present. Our results suggest that changing earthworm species composition leads to changing resource use, which alters the fate of organic carbon in the forest floor and soil and could potentially affect long-term SOM dynamics in temperate forests.

  1. Node-avoiding Levy flight - A numerical test of the epsilon expansion. [random walk

    NASA Technical Reports Server (NTRS)

    Halley, J. W.; Nakanishi, H.

    1985-01-01

    A study is conducted of an extension of Levy flight to include self-repulsion in the path of the walk. The extension is called node-avoiding Levy flight and its equivalence to the n approaches 0 limit of a statistical mechanical model for a magnetic system with long-range interactions between the spins is shown. By use of this equivalence it is possible to make a detailed comparison beween the results of the epsilon expansion for the magnetic model, a Monte Carlo simulation of the Levy flight model, and the results of a Flory-type argument. This is the first comparison of the epsilon expansion for epsilon much less than 1 with a numerical simulation for any model. Some speculations are made on applications of the model of node-avoiding Levy flight.

  2. Testing the disgust conditioning theory of food-avoidance in adolescents with recent onset anorexia nervosa.

    PubMed

    Hildebrandt, Tom; Grotzinger, Andrew; Reddan, Marianne; Greif, Rebecca; Levy, Ifat; Goodman, Wayne; Schiller, Daniela

    2015-08-01

    Anorexia nervosa is characterized by chronic food avoidance that is resistant to change. Disgust conditioning offers one potential unexplored mechanism for explaining this behavioral disturbance because of its specific role in facilitating food avoidance in adaptive situations. A food based reversal learning paradigm was used to study response flexibility in 14 adolescent females with restricting subtype anorexia nervosa (AN-R) and 15 healthy control (HC) participants. Expectancy ratings were coded as a behavioral measure of flexibility and electromyography recordings from the levator labii (disgust), zygomaticus major (pleasure), and corrugator (general negative affect) provided psychophysiological measures of emotion. Response inflexibility was higher for participants with AN-R, as evidenced by lower extinction and updated expectancy ratings during reversal. EMG responses to food stimuli were predictive of both extinction and new learning. Among AN-R patients, disgust specific responses to food were associated with impaired extinction, as were elevated pleasure responses to the cued absence of food. Disgust conditioning appears to influence food learning in acutely ill patients with AN-R and may be maintained by counter-regulatory acquisition of a pleasure response to food avoidance and an aversive response to food presence. Developing strategies to target disgust may improve existing interventions for patients with AN. PMID:26131915

  3. Earthworm-vegetation-soil relationships in the Romanian Carpathians

    Microsoft Academic Search

    Victor V. Pop

    1997-01-01

    The structure of six earthworm community patterns, labelled by the name of the characteristic species, is presented. In forest ecosystems the earthworm communities are characteristic for classes of vegetation (coniferous, beech, beech-hornbeam and oak-hornbeam), while in grasslands they correspond to alliances related by their trophicity (eu-, mezobasic, oligobasic). A table shows the earthworm-vegetation-soil relationships.

  4. Earthworms helping economy, improving ecology and protecting health

    Microsoft Academic Search

    Kangmin Li; Peizhen Li; Hongtao Li

    2010-01-01

    Earthworms can treat organic garbage, livestock manure and poultry droppings and turn them into premium organic fertilisers, because humus only exists in earthworm feces and castings, compared with other fertilisers. Earthworms can also supply quality animal protein as feed, and offer the best raw materials for the biochemical and pharmaceutical industries. Vermiculture should be put into a whole circular economy

  5. Earthworms, Dirt, and Rotten Leaves: An Exploration in Ecology.

    ERIC Educational Resources Information Center

    McLaughlin, Molly

    1994-01-01

    This article provides a model for inviting children to "an exploration in ecology" by observing earthworms. It gives reasons to explore earthworms and guides the investigator through a detailed examination of the worms to answer 21 observation questions. Explores the ways in which earthworms interact with their environment. (LZ)

  6. Effects of heavy metals on earthworms along contamination gradients in organic rich soils

    Microsoft Academic Search

    Tuomas Lukkari; Mirka Taavitsainen; Ari Väisänen; Jari Haimi

    2004-01-01

    Earthworm communities and metal (bio)availability to earthworms along contamination gradients was studied in order to support chemical analyses in risk assessment of metal contaminated soils. Earthworms were sampled in three metal contaminated areas with different habitat and soil properties in Finland. Earthworm and soil samples were collected at three distances (1, 2, and 4km) from the emission sources. Earthworms were

  7. A test of a disease-avoidance model of animal phobias.

    PubMed

    Matchett, G; Davey, G C

    1991-01-01

    This study examined the relationship between disgust/contamination sensitivity and fear of animals. The results suggested that sensitivity to disgust and contamination was directly related to scores on the animal phobia and fear of illness and death sub-scales of the Fear Survey Schedule (FSS). Further analysis suggested that disgust/contamination sensitivity was related only to fear of certain groups of animals: namely those animals that are not considered to attack and harm human beings but are considered fear-evoking (e.g. rat, spider, cockroach), and those animals that are normally considered to evoke revulsion (e.g. maggot, snail, slug). Disgust/contamination sensitivity was not related to fear of animals that are considered highly likely to attack and harm human beings (e.g. tiger, lion, shark). These results are discussed as support for a disease-avoidance model of common animal fears. PMID:2012593

  8. Helicopter Field Testing of NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) System fully Integrated with the Morpheus Vertical Test Bed Avionics

    NASA Technical Reports Server (NTRS)

    Epp, Chirold D.; Robertson, Edward A.; Ruthishauser, David K.

    2013-01-01

    The Autonomous Landing and Hazard Avoidance Technology (ALHAT) Project was chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with real-time terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. The ALHAT System must be capable of identifying and avoiding surface hazards to enable a safe and accurate landing to within tens of meters of designated and certified landing sites anywhere on a planetary surface under any lighting conditions. This is accomplished with the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN). The NASA plan for the ALHAT technology is to perform the TRL6 closed loop demonstration on the Morpheus Vertical Test Bed (VTB). The first Morpheus vehicle was lost in August of 2012 during free-flight testing at Kennedy Space Center (KSC), so the decision was made to perform a helicopter test of the integrated ALHAT System with the Morpheus avionics over the ALHAT planetary hazard field at KSC. The KSC helicopter tests included flight profiles approximating planetary approaches, with the entire ALHAT system interfaced with all appropriate Morpheus subsystems and operated in real-time. During these helicopter flights, the ALHAT system imaged the simulated lunar terrain constructed in FY2012 to support ALHAT/Morpheus testing at KSC. To the best of our knowledge, this represents the highest fidelity testing of a system of this kind to date. During this helicopter testing, two new Morpheus landers were under construction at the Johnson Space Center to support the objective of an integrated ALHAT/Morpheus free-flight demonstration. This paper provides an overview of this helicopter flight test activity, including results and lessons learned, and also provides an overview of recent integrated testing of ALHAT on the second Morpheus vehicle.

  9. tivity of each subject was assessed in 2 approach-avoidance conflict tests by pairing food

    E-print Network

    Paris-Sud XI, Université de

    with a stressful stimulus (ie the novelty of the environment in the 1st test, a surprise effect in the 2nd test that a high degree of stress in conspecifics alters this social buffering effect by increasing levels- provement due to SC overseeding. The effects of outdoor wintering on the variations in weight and body

  10. Approach-Avoidance Motivational Profiles in Early Adolescents to the PACER Fitness Test

    ERIC Educational Resources Information Center

    Garn, Alex; Sun, Haichun

    2009-01-01

    The use of fitness testing is a practical means for measuring components of health-related fitness, but there is currently substantial debate over the motivating effects of these tests. Therefore, the purpose of this study was to examine the cross-fertilization of achievement and friendship goal profiles for early adolescents involved in the…

  11. Avoiding the {open_quotes}definition{close_quotes} pitfall to a comprehensive test ban

    SciTech Connect

    Bunn, G.; Timerbaev, R.

    1993-05-01

    Recently approved US legislation and a new US administration have brought an end to 12 years of American opposition to a comprehensive test ban (CTB). Signed by President Bush on October 2, 1992, the new law imposes a moratorium on US nuclear tests until July and possibly longer, permits up to 15 nuclear tests to improve the safety and reliability of nuclear weapons from the end of this moratorium until October 1996, and prohibits US tests after that unless another country tests. It also calls on the president to submit a plan for resumption of negotiations to end testing. President Bill Clinton, in his February 12, 1993 letter to Senate Majority Leader George Mitchell (D-ME) supporting this legislation, said his administration was now reviewing questions {open_quotes}of forum and modalities for negotiating a CTB...{close_quotes} Moreover, Presidents Clinton and Boris Yeltsin, at their April summit in Vancouver, {open_quotes}agreed that negotiations on a multilateral nuclear test ban should commence at an early date.{close_quotes}

  12. POPULATION DYNAMICS OF AMBIENT AND ALTERED EARTHWORM COMMUNITIES IN ROW-CROP AGROECOSYSTEMS IN OHIO, USA

    EPA Science Inventory

    Although earthworms are known to influence agroecosystem processes, there are relatively few long-term studies addressing population dynamics under cropping systems in which earthworm populations were intentionally altered. We assessed earthworm communities from fall 1994 to spr...

  13. Avoiding Split Attention in Computer-Based Testing: Is Neglecting Additional Information Facilitative?

    ERIC Educational Resources Information Center

    Jarodzka, Halszka; Janssen, Noortje; Kirschner, Paul A.; Erkens, Gijsbert

    2015-01-01

    This study investigated whether design guidelines for computer-based learning can be applied to computer-based testing (CBT). Twenty-two students completed a CBT exam with half of the questions presented in a split-screen format that was analogous to the original paper-and-pencil version and half in an integrated format. Results show that students…

  14. Anisopary in compost earthworm reproductive strategies (Oligochaeta)

    Microsoft Academic Search

    W. J. Meyer; H. Bouwman

    1997-01-01

    Individual differences in the number of hatchlings and cocoons produced by Eisenia fetida have been recorded. We propose to call this phenomenon anisopary — unequal reproduction (an — not, iso — the same, parere — to produce). The reproduction of individual partners from pairs of E. fetida were studied. The earthworms were mated for 72 h and then separated. In

  15. Easy Extraction of Roundworms from Earthworm Hosts.

    ERIC Educational Resources Information Center

    Eyster, Linda S.; Fried, Bernard

    2000-01-01

    Describes the inexpensive and safe method of using roundworms in the classroom or laboratories. Because parasitic infections are so common, students should learn about worms. Provides statistics on just how many people have a worm infection in the world. Explains how to study living nematodes, and obtain and use earthworms. (Contains 13…

  16. Visualization of enzyme activities inside earthworm pores

    NASA Astrophysics Data System (ADS)

    Hoang, Duyen; Razavi, Bahar S.

    2015-04-01

    In extremely dynamic microhabitats as bio-pores made by earthworm, the in situ enzyme activities are assumed as a footprint of complex biotic interactions. Our study focused on the effect of earthworm on the enzyme activities inside bio-pores and visualizing the differences between bio-pores and earthworm-free soil by zymography technique (Spohn and Kuzyakov, 2013). For the first time, we aimed at quantitative imaging of enzyme activities in bio-pores. Lumbricus terrestris L. was placed into transparent box (15×20×15cm). After two weeks when bio-pore systems were formed by earthworms, we visualized in situ enzyme activities of five hydrolytic enzymes (?-glucosidase, cellobiohydrolase, chitinase, xylanase, leucine-aminopeptidase, and phosphatase. Zymography showed higher activity of ?-glucosidase, chitinase, xylanase and phosphatase in biopores comparing to bulk soil. However, the differences in activity of cellobiohydrolase and leucine aminopeptidase between bio-pore and bulk soil were less pronounced. This demonstrated an applicability of zymography approach to monitor and to distinguish the in situ activity of hydrolytic enzymes in soil biopores.

  17. Earthworm symbiont Verminephrobacter eiseniae mediates natural transformation within host egg capsules using type IV pili.

    PubMed

    Davidson, Seana K; Dulla, Glenn F; Go, Ruth A; Stahl, David A; Pinel, Nicolás

    2014-01-01

    The dense microbial communities commonly associated with plants and animals should offer many opportunities for horizontal gene transfer through described mechanisms of DNA exchange including natural transformation (NT). However, studies of the significance of NT have focused primarily on pathogens. The study presented here demonstrates highly efficient DNA exchange by NT in a common symbiont of earthworms. The obligate bacterial symbiont Verminephrobacter eiseniae is a member of a microbial consortium of the earthworm Eisenia fetida that is transmitted into the egg capsules to colonize the embryonic worms. In the study presented here, by testing for transformants under different conditions in culture, we demonstrate that V. eiseniae can incorporate free DNA from the environment, that competency is regulated by environmental factors, and that it is sequence specific. Mutations in the type IV pili of V. eiseniae resulted in loss of DNA uptake, implicating the type IV pilus (TFP) apparatus in DNA uptake. Furthermore, injection of DNA carrying antibiotic-resistance genes into egg capsules resulted in transformants within the capsule, demonstrating the relevance of DNA uptake within the earthworm system. The ability to take up species-specific DNA from the environment may explain the maintenance of the relatively large, intact genome of this long-associated obligate symbiont, and provides a mechanism for acquisition of foreign genes within the earthworm system. PMID:25400622

  18. A field test for host fruit odour discrimination and avoidance behaviour for Rhagoletis pomonella flies in the western United States.

    PubMed

    Sim, S B; Mattsson, M; Feder, Jasmine L; Cha, D H; Yee, W L; Goughnour, R B; Linn, C E; Feder, Jeffrey L

    2012-05-01

    Prezygotic isolation due to habitat choice is important to many models of speciation-with-gene-flow. Habitat choice is usually thought to occur through positive preferences of organisms for particular environments. However, avoidance of non-natal environments may also play a role in choice and have repercussions for post-zygotic isolation that preference does not. The recent host shift of Rhagoletis pomonella (Diptera: Tephritidae) from downy hawthorn, Crataegus mollis, to introduced apple, Malus domestica, in the eastern United States is a model for speciation-with-gene-flow. However, the fly is also present in the western United States where it was likely introduced via infested apples ? 60 years ago. R. pomonella now attacks two additional hawthorns in the west, the native C. douglasii (black hawthorn) and the introduced C. monogyna (English ornamental hawthorn). Flight tunnel tests have shown that western apple-, C. douglasii- and C. monogyna-origin flies all positively orient to fruit volatile blends of their respective natal hosts in flight tunnel assays. Here, we show that these laboratory differences translate to nature through field-trapping studies of flies in the state of Washington. Moreover, western R. pomonella display both positive orientation to their respective natal fruit volatiles and avoidance behaviour (negative orientation) to non-natal volatiles. Our results are consistent with the existence of behaviourally differentiated host races of R. pomonella in the west. In addition, the rapid evolution of avoidance behaviour appears to be a general phenomenon for R. pomonella during host shifts, as the eastern apple and downy hawthorn host races also are antagonized by non-natal fruit volatiles. PMID:22435643

  19. Copper avoidance and mortality of juvenile brown trout (Salmo trutta) in tests with copper-sulfate-treated water from West Branch Reservoir, Putnam County, New York

    USGS Publications Warehouse

    Baldigo, B.P.; Baudanza, T.P.

    2001-01-01

    Copper-avoidance tests and acute-toxicity (mortality) tests on hatchery-reared, young-of- the-year brown trout (salmo trutta) were conducted with water from West Branch Reservoir to assess the avoidance response to copper sulfate treatment, which is used occasionally by New York City Department of Environmental Protection to decrease phytoplankton populations in the reservoir. Avoidance-test results indicate that juvenile brown trout tend to avoid dissolved copper concentrations greater than about 55 ?g/L (micrograms per liter), which is the approximate avoidance-response threshold. The mean net avoidance response of brown trout to dissolved copper concentrations of 70 and 100 ?g/L, and possibly 80 ?g/L, was significantly different (at a = 0.1) from the mean net avoidance response of fish to control (untreated) water and to treated water at most other tested concentrations. Mortality-test results indicate that the 96-hr median lethal concentration (LC50) of dissolved copper was 61.5 ?g/L. All (100 percent) of the brown trout died at a dissolved copper concentration of 85 ?g/L, many died at concentrations of 62 ?g/L and 70 ?g/L, and none died in the control waters (7 ?g/L) or at concentrations of 10, 20, or 45 ?g/L. The estimated concentration of dissolved copper that caused fish mortality (threshold) was 53.5 ?g/L, virtually equivalent to the avoidance-response threshold. Additional factors that could affect the copper-avoidance and mortality response of individual brown trout and their populations in West Branch Reservoir include seasonal variations in certain water-quality parameters, copper-treatment regimes, natural fish distributions during treatment, and increased tolerance due to acclimation. These warrant additional study before the findings from this study can be used to predict the effects that copper sulfate treatments have on resident fish populations in New York City reservoirs.

  20. Avoiding Snakebites

    MedlinePLUS

    ... Snakebites Avoiding Snakebites How can I avoid snakebites? Snakes are most active in the spring, early summer ... warm and outdoor activities are popular. Although most snakes are not poisonous, there are several kinds of ...

  1. Activity of earthworm in Latosol under simulated acid rain stress.

    PubMed

    Zhang, Jia-En; Yu, Jiayu; Ouyang, Ying

    2015-01-01

    Acid rain is still an issue of environmental concerns. This study investigated the impacts of simulated acid rain (SAR) upon earthworm activity from the Latosol (acidic red soil). Laboratory experiment was performed by leaching the soil columns grown with earthworms (Eisenia fetida) at the SAR pH levels ranged from 2.0 to 6.5 over a 34-day period. Results showed that earthworms tended to escape from the soil and eventually died for the SAR at pH = 2.0 as a result of acid toxicity. The catalase activity in the earthworms decreased with the SAR pH levels, whereas the superoxide dismutases activity in the earthworms showed a fluctuate pattern: decreasing from pH 6.5 to 5.0 and increasing from pH 5.0 to 4.0. Results implied that the growth of earthworms was retarded at the SAR pH ? 3.0. PMID:25351717

  2. Effect of earthworms (Eisenia fetida) on the fractionation and bioavailability of rare earth elements in nine Chinese soils.

    PubMed

    Wen, Bei; Liu, Ying; Hu, Xiao-yu; Shan, Xiao-quan

    2006-05-01

    The effect of earthworm (Eisenia fetida) activity on soil pH, dissolved organic carbon (DOC), fraction distribution pattern and bioavailability of rare earth elements (REEs) Y, La, Ce, Pr and Nd in nine Chinese soils were investigated using pot experiments. A three-step extraction procedure recommended by the European Community (Standards, Measurements and Testing Programme) was used to fractionate REEs in soils into water soluble, exchangeable and carbonate bound (B1), Fe- and Mn-oxides bound (B2) and organic matter and sulfide bound (B3). Inoculated with earthworms, the soil pH, DOC and water-soluble rare earth elements fraction increased. A significant correlation was obtained between the increased DOC and the increased water-soluble REEs. REEs in fraction B1 increased after earthworm inoculation, while those in fraction B3 decreased. No significant differences were observed for REEs in fraction B2. The biomass and the concentrations of REEs in wheat shoots and roots increased after the treatment with earthworms. The results demonstrated that earthworm activity increased the mobility and bioavailability of REEs in soils. PMID:16289225

  3. Interaction of citrate-coated silver nanoparticles with earthworm coelomic fluid and related cytotoxicity in Eisenia andrei.

    PubMed

    Kwak, Jin Il; Lee, Woo-Mi; Kim, Shin Woong; An, Youn-Joo

    2014-11-01

    Understanding the interaction of nanoparticles with biological fluid is important for predicting the behavior and toxicity of nanoparticles in living systems. The earthworm Eisenia andrei was exposed to citrate-coated silver nanoparticles (cAgNPs), and the interaction of cAgNPs with earthworm coelomic fluid (ECF), the cytotoxicity of cAgNPs in earthworm coelomocytes was assessed. The neutral red retention assay showed a reduction in lysosomal stability after exposure. The toxicity of silver ions dissolved from cAgNPs in the soil medium was not significant. The aggregation and dissolution of cAgNPs increased in ECF, which contains various electrolytes that alter the properties of nanoparticles, and their subsequent toxicity. Microscopic and dissolution studies demonstrated that the aggregation of cAgNPs rapidly increased, and readily dissolved in ECF. The bioavailability of cAgNPs to earthworms induced lysosomal cytotoxicity. This is the first report to test the interaction and lysosomal cytotoxicity of nanoparticles in earthworm biofluids. PMID:24532537

  4. Root Foraging Influences Plant Growth Responses to Earthworm Foraging

    PubMed Central

    Cameron, Erin K.; Cahill, James F.; Bayne, Erin M.

    2014-01-01

    Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L.) impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants. PMID:25268503

  5. Root foraging influences plant growth responses to earthworm foraging.

    PubMed

    Cameron, Erin K; Cahill, James F; Bayne, Erin M

    2014-01-01

    Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L.) impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants. PMID:25268503

  6. Checklist of earthworms (Oligochaeta: Lumbricidae) from Germany.

    PubMed

    Lehmitz, Ricarda; Römbke, Jörg; Jänsch, Stephan; Krück, Stefanie; Beylich, Anneke; Graefe, Ulfert

    2014-01-01

    A checklist of the German earthworm fauna (Oligochaeta: Lumbricidae) is presented, including published data, data from reports, diploma- and PhD- theses as well as unpublished data from museum collections, research institutions and private persons. Overall, 16,000 datasets were analyzed to produce the first German checklist of Lumbricidae. The checklist comprises 46 earthworm species from 15 genera and provides ecological information, zoogeographical distribution type and information on the species distribution in Germany. Only one species, Lumbricus badensis Michaelsen, 1907, is endemic to Germany, whereas 41% are peregrine. As there are 14 species occurring exclusively in the southern or eastern part of Germany, the species numbers in German regions increase from north to south. PMID:25283656

  7. Removal of mercury from soil with earthworms

    SciTech Connect

    Dorfman, D. [Monmouth Coll., West Long Branch, NJ (United States)

    1994-12-31

    Earthworms can live in soils containing high quantities of mercury, lead, and zinc. The worms (Lumbricus terrestris) concentrate these heavy metals in their tissues. The use of these worms to reduce the quantities of mercury and other heavy metals in soils may be practical. In July, 1993, a preliminary study was made using earthworms and soils with differing amounts of mercury, The quantities were 0.0 grams, 0.5 grams, and 1.0 grams of mercury as mercuric chloride. Earthworms were placed into these soils for two or more weeks, then harvested. The worms were rinsed with deionized water, then dissolved in nitric acid. Each sample was prepared for analysis with the addition of HNO{sub 3}, H{sub 2}SO{sub 4}, potassium permanganate, and hydrozylamine hydrochloride. A Jerome Instrument gold foil analyzer was used to determine levels of mercury after volatilizing the sample with stannous chloride. Worms exposed to contaminated soils remove 50 to 1,400 times as much mercury as do worms in control soils. In a hypothetical case, a site contaminated with one pound of mercury, 1,000 to 45,000 worms would be required to reduce mercury levels to background levels in the soil (about 250 ppb). After harvesting worms in contaminated soil they could be dried (90% of their weight is water), and the mercury regained by chemical processes. Soil conducive to earthworm survival is required. This includes a well aerated loamy soil, proper pH (7.0), and periodic watering and feeding. There are several methods of harvesting worms, including flooding and electricity. Large numbers of worms can be obtained from commercial growers.

  8. Determination of arsenic compounds in earthworms

    SciTech Connect

    Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W. [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry] [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry; Francesconi, K. [Odense Univ. (Denmark). Inst. of Biology] [Odense Univ. (Denmark). Inst. of Biology

    1998-08-01

    Earthworms and soil collected from six sites in Styria, Austria, were investigated for total arsenic concentrations by ICP-MS and for arsenic compounds by HPLC-ICP-MS. Total arsenic concentrations ranged from 3.2 to 17.9 mg/kg dry weight in the worms and from 5.0 to 79.7 mg/kg dry weight in the soil samples. There was no strict correlation between the total arsenic concentrations in the worms and soil. Arsenic compounds were extracted from soil and a freeze-dried earthworm sample with a methanol/water mixture (9:1, v/v). The extracts were evaporated to dryness, redissolved in water, and chromatographed on an anion- and a cation-exchange column. Arsenic compounds were identified by comparison of the retention times with known standards. Only traces of arsenic acid could be extracted from the soil with the methanol/water (9:1, v/v) mixture. The major arsenic compounds detected in the extracts of the earthworms were arsenous acid and arsenic acid. Arsenobetaine was present as a minor constituent, and traces of dimethylarsinic acid were also detected. Two dimethylarsinoyltribosides were also identified in the extracts by co-chromatography with standard compounds. This is the first report of the presence of dimethylarsinoylribosides in a terrestrial organism. Two other minor arsenic species were present in the extract, but their retention times did not match with the retention times of the available standards.

  9. Exotic earthworms of great lakes forests: A search for indicator plant species in maple forests

    Microsoft Academic Search

    Kathryn Corio; Amy Wolf; Michael Draney; Gary Fewless

    2009-01-01

    The invasion of exotic earthworms in previously earthworm-free northern deciduous forests has been linked to the disappearance of forest floor litter, declines in plant species richness, and the development of monotypic stands of Carex pensylvanica. However, the impact of exotic earthworms on the regeneration of trees and understory plants is largely unknown. We examined the relationships between earthworm density, plant

  10. The effects of tree plantation rotation on earthworm abundance and biomass in Hawaii

    Microsoft Academic Search

    Yiqing Li; Amy Shimabukuro-Madden; Bruce W. Mathews

    2010-01-01

    Earthworms play a large part in soil functioning but the effects and implications of earthworm invasions are not well known in comparison with above-ground invasive species. Few studies have examined land-use change and tree plantation rotation effects on earthworm invasions. Using replicated reciprocal experimentation, this study examined the effects of tree plantation rotation on earthworm abundance, biomass, and community structure

  11. The effect of tributyltin-oxide on earthworms, springtails, and plants in artificial and natural soils.

    PubMed

    Römbke, J; Jänsch, S; Junker, T; Pohl, B; Scheffczyk, A; Schallnass, H-J

    2007-05-01

    Chemical bioavailability in Organisation for Economic Co-operation and Development (OECD) artificial soil can contrast with bioavailability in natural soils and produce ecotoxicologic benchmarks that are not representative of species' exposure conditions in the field. Initially, reproduction and growth of earthworm and Collembolan species, and early seedling growth of a dicotyledonous plant species, in nine natural soils (with a wide range of physicochemical properties) and in OECD soil were evaluated. Soils that supported reproduction and growth of the test species were then used to investigate the toxicity of tributyltin-oxide (TBT-O). Natural soils caused greater toxicity of TBT-O to earthworms (EC(50) values varied from 0.5 to 4.7 mg/kg soil dry weight [dw]) compared with toxicity in OECD soil (EC(50) = 13.4 mg/kg dw). Collembolans were less sensitive to TBT-O than earthworms in natural soils, with EC(50) values ranging from 23.4 to 177.8 mg/kg dw. In contrast, the toxicity of TBT-O to collembolans in OECD soil (EC(50) = 104.0 mg/kg dw) was within the range of EC(50) values in natural soils. Phytotoxicity tests revealed even greater difference between the effects in natural soils (EC(50) values ranged from 10.7 to 189.2 mg/kg dw) and in OECD soil (EC(50) = 535.5 mg/kg dw) compared with results of the earthworm tests. Studies also showed that EC(50) values were a more robust end point compared with EC(10) values based on comparisons of coefficients of variation. These results show that toxicity testing should include studies with natural soils in addition to OECD soil to better reflect exposure conditions in the field. PMID:17380235

  12. BIOTIC INTERACTIONS MODIFY THE TRANSFER OF CESIUM137 IN A SOIL–EARTHWORM–PLANT–SNAIL FOOD WEB

    Microsoft Academic Search

    Clémentine Fritsch; Renaud Scheifler; Karine Beaugelin-Seiller; Philippe Hubert; Michaël Cśurdassier; Annette de Vaufleury; Pierre-Marie Badot

    2008-01-01

    137 Cs) from a contaminated (130 Bq\\/kg) deciduous forest soil to the lettuce Lactuca sativa and to the snail Cantareus aspersus (formerly Helix aspersa) in two laboratory experiments. In the first experiment, the International Organization for Stan- dardization 15952 test was used to expose snails for five weeks to contaminated soil with or without earthworms. In these conditions, the presence

  13. Cadmium, nickel, lead, and zinc in earthworms from roadside soil

    Microsoft Academic Search

    Charles D. Gish; Robert E. Christensen

    1973-01-01

    Cd, Ni, Pb, and Zn in soils and earthworms along two Maryland highways decreased with increasing distance (10, 20, 40, 80, and 160 ft) from the roadway. Metals were quantified by atomic absorption spectrophotometry. Metal residues were higher at the location along each highway where traffic volume was greater. Correlations between residues in earthworms and soil decreased with decreasing atomic

  14. Earthworm communities under an agricultural intensification gradient in Colombia

    Microsoft Academic Search

    T. Decaëns; J. J. Jiménez

    2002-01-01

    This study was carried out in the Eastern Plains of Colombia and assessed the impact of agricultural intensification on the structure of earthworm communities. Earthworms were hand-sorted in a variety of agroecosystems of increasing intensity, from natural savanna to pastures and annual crops. An agricultural intensification index was used to rank systems along an intensification gradient, i.e. from native savanna

  15. Association of Earthworm-Denitrifier Interactions with Increased Emission of Nitrous Oxide from Soil Mesocosms Amended with Crop Residue? †

    PubMed Central

    Nebert, Lucas D.; Bloem, Jaap; Lubbers, Ingrid M.; van Groenigen, Jan Willem

    2011-01-01

    Earthworm activity is known to increase emissions of nitrous oxide (N2O) from arable soils. Earthworm gut, casts, and burrows have exhibited higher denitrification activities than the bulk soil, implicating priming of denitrifying organisms as a possible mechanism for this effect. Furthermore, the earthworm feeding strategy may drive N2O emissions, as it determines access to fresh organic matter for denitrification. Here, we determined whether interactions between earthworm feeding strategy and the soil denitrifier community can predict N2O emissions from the soil. We set up a 90-day mesocosm experiment in which 15N-labeled maize (Zea mays L.) was either mixed in or applied on top of the soil in the presence or absence of the epigeic earthworm Lumbricus rubellus and/or the endogeic earthworm Aporrectodea caliginosa. We measured N2O fluxes and tested the bulk soil for denitrification enzyme activity and the abundance of 16S rRNA and denitrifier genes nirS and nosZ through real-time quantitative PCR. Compared to the control, L. rubellus increased denitrification enzyme activity and N2O emissions on days 21 and 90 (day 21, P = 0.034 and P = 0.002, respectively; day 90, P = 0.001 and P = 0.007, respectively), as well as cumulative N2O emissions (76%; P = 0.014). A. caliginosa activity led to a transient increase of N2O emissions on days 8 to 18 of the experiment. Abundance of nosZ was significantly increased (100%) on day 90 in the treatment mixture containing L. rubellus alone. We conclude that L. rubellus increased cumulative N2O emissions by affecting denitrifier community activity via incorporation of fresh residue into the soil and supplying a steady, labile carbon source. PMID:21515716

  16. Trade-offs between nitrous oxide emission and C-sequestration in the soil: the role of earthworms

    NASA Astrophysics Data System (ADS)

    van Groenigen, J.; Lubbers, I. M.; Giannopoulos, G.

    2008-12-01

    The rapidly rising concentrations of the greenhouse gas carbon dioxide (CO2) in the atmosphere has spurred the interest in soils as a potential carbon (C) sink. However, there are many reports indicating that C- sequestration is often negated by elevated emissions of the potent greenhouse gas nitrous oxide (N2O). It is not yet clear what the driving factors behind this trade-off are, nor how it can be avoided. We suggest that earthworm activity may be partly responsible for the trade-off. Earthworm activity is increasingly recognized as being beneficial to C-sequestration through stabilization of SOM. We report experimental results suggesting that they can also lead to strongly elevated N2O-emissions. In a first experiment, dried grass residue (Lolium perenne) was applied at the top of a loamy soil or mixed through the soil, and N2O-emission was followed for three months. Treatments included presence of the epigeic earthworm Lumbricus rubellus and the anecic earthworm Aporrectodea longa. Cumulative N2O-emissions increased significantly for both species. The strongest effect was measured for L. rubellus, where N2O-emissions significantly increased from 55.7 to 789.1 micro g N2O-N kg- 1 soil. This effect was only observed when residue was applied on top of the soil. In a second experiment we determined the effect of epigeic (L. rubellus) and endogeic (Aporrectodea caliginosa) earthworms on N2O-emissions for two different soil types (loam and sand) in the presence of 15N-labeled radish residue (Raphanus sativus subsp. oleiferus). Both species showed significant increases in N2O-emissions, which differed with residue application method and soil type. N2O- emissions were generally larger in loamy soils and the strongest effect was measured for A. caliginosa when residue was mixed into the soil, increasing emissions from 1350.1 to 2223.2 micro g N2O-N kg- 1 soil. L. rubellus only resulted in elevated N2O-emissions when residue was applied on top. These studies make it clear that elevated N2O-emissions due to earthworm activity is a widespread phenomenon, and that the nature of earthworm-induced effect is largely controlled by its feeding habit and interactions with other species. Our results contribute to understanding the important but intricate relations between (functional) biodiversity and the soil greenhouse gas balance.

  17. Testing the nutritional-limitation, predator-avoidance, and storm-avoidance hypotheses for restricted sea otter habitat use in the Aleutian Islands, Alaska

    USGS Publications Warehouse

    Stewart, Nathan L.; Konar, Brenda; Tinker, M. Tim

    2015-01-01

    Sea otters (Enhydra lutris) inhabiting the Aleutian Islands have stabilized at low abundance levels following a decline and currently exhibit restricted habitat-utilization patterns. Possible explanations for restricted habitat use by sea otters can be classified into two fundamentally different processes, bottom-up and top-down forcing. Bottom-up hypotheses argue that changes in the availability or nutritional quality of prey resources have led to the selective use of habitats that support the highest quality prey. In contrast, top-down hypotheses argue that increases in predation pressure from killer whales have led to the selective use of habitats that provide the most effective refuge from killer whale predation. A third hypothesis suggests that current restricted habitat use is based on a need for protection from storms. We tested all three hypotheses for restricted habitat use by comparing currently used and historically used sea otter foraging locations for: (1) prey availability and quality, (2) structural habitat complexity, and (3) exposure to prevailing storms. Our findings suggest that current use is based on physical habitat complexity and not on prey availability, prey quality, or protection from storms, providing further evidence for killer whale predation as a cause for restricted sea otter habitat use in the Aleutian Islands.

  18. Avoiding Absurdity

    Microsoft Academic Search

    Glen Staszewski

    2006-01-01

    American courts have always interpreted statutes contrary to their plain meaning to avoid absurd results. John Manning, a prominent new textualist scholar, has recently challenged the legitimacy of the \\

  19. Toxic effects of PCDD/Fs mixtures on Eisenia andrei earthworms.

    PubMed

    Belmeskine, Hayet; Haddad, Sami; Vandelac, Louise; Sauvé, Sébastien; Fournier, Michel

    2012-06-01

    The earthworms Eisenia andrei were used to study the toxicity of PCDD/Fs mixtures to earthworms during 28 day of exposure. The experiments were performed on artificial soils contaminated with dioxins at levels of C1 (0.1 ng 2, 3, 7, 8-TCDD/g soil), C2 (1 ng 2, 3, 7, 8-TCDD/g soil) and C3 (1.5 ng 2, 3, 7, 8-TCDD/g soil). Effects of PCDD/Fs on survival, growth rate and immune responses; phagocytosis and NK-like cell activity, were determined. No mortality was observed at the lowest concentration (C1), while mortalities of 10 and 100% were noted at the highest concentrations tested C2 and C3, respectively. A significant reduction in growth rate was obtained at C2 and no effects at C1. Additionally, an inhibition of phagocytic activity and efficiency was observed at higher concentrations. In contrast, an enhancement of NK-like cell activity was shown at lower concentrations. Based on our results, we hypothesize that the PCDD/Fs mixtures tested at levels equal or higher to C2 (1 ng 2378-TCDD/g soil), lead to adverse effects on biotic potential and immune functions in E. andrei earthworms. PMID:22401954

  20. The effect of anthropogenic arsenic contamination on the earthworm microbiome.

    PubMed

    Pass, Daniel Antony; Morgan, Andrew John; Read, Daniel S; Field, Dawn; Weightman, Andrew J; Kille, Peter

    2015-06-01

    Earthworms are globally distributed and perform essential roles for soil health and microbial structure. We have investigated the effect of an anthropogenic contamination gradient on the bacterial community of the keystone ecological species Lumbricus rubellus through utilizing 16S rRNA pyrosequencing for the first time to establish the microbiome of the host and surrounding soil. The earthworm-associated microbiome differs from the surrounding environment which appears to be a result of both filtering and stimulation likely linked to the altered environment associated with the gut micro-habitat (neutral pH, anoxia and increased carbon substrates). We identified a core earthworm community comprising Proteobacteria (?50%) and Actinobacteria (?30%), with lower abundances of Bacteroidetes (?6%) and Acidobacteria (?3%). In addition to the known earthworm symbiont (Verminephrobacter sp.), we identified a potential host-associated Gammaproteobacteria species (Serratia sp.) that was absent from soil yet observed in most earthworms. Although a distinct bacterial community defines these earthworms, clear family- and species-level modification were observed along an arsenic and iron contamination gradient. Several taxa observed in uncontaminated control microbiomes are suppressed by metal/metalloid field exposure, including eradication of the hereto ubiquitously associated Verminephrobacter symbiont, which raises implications to its functional role in the earthworm microbiome. PMID:25404571

  1. Vermistabilization of textile mill sludge spiked with poultry droppings by an epigeic earthworm Eisenia foetida.

    PubMed

    Garg, V K; Kaushik, Priya

    2005-06-01

    Investigations were made to explore the potential of an epigeic earthworm Eisenia foetida to transform textile mill sludge spiked with poultry droppings in to value added product, i.e., vermicompost. The growth and reproduction of E. foetida was monitored in a range of different feed mixtures for 77 days in the laboratory under controlled experimental conditions. The maximum growth was recorded in 100% cow dung (CD). Replacement of poultry droppings by cow dung in feed mixtures and vice versa had little or no effect on worm growth rate and reproduction potential. Worms grew and reproduced favourably in 70% poultry droppings (PD)+30% solid textile mill sludge (STMS) and 60% PD+40% STMS feed mixtures. Greater percentage of STMS in the feed mixture significantly affected the biomass gain and cocoon production. Net weight gain by earthworms in 100% CD was 2.9-18.2 fold higher than different STMS containing feed mixtures. The mean number of cocoon production was between 23.4+/-4.65 (in 100% CD) and 3.6+/-1.04 (in 50% PD+50% STMS) cocoons earthworm(-1) for different feed mixtures tested. Vermicomposting resulted in significant reduction in C:N ratio and increase in nitrogen and phosphorus contents. Total potassium, total calcium and heavy metals (Fe, Zn, Pb and Cd) contents were lower in the final product than initial feed mixtures. Our trials demonstrated vermicomposting as an alternate technology for the recycling and environmentally safe disposal/management of textile mill sludge using an epigeic earthworm E. foetida if mixed with poultry droppings. PMID:15668203

  2. A filter circuit board for the Earthworm Seismic Data Acquisition System

    USGS Publications Warehouse

    Jensen, Edward Gray

    2000-01-01

    The Earthworm system is a seismic network data acquisition and processing system used by the Northern California Seismic Network as well as many other seismic networks. The input to the system is comprised of many realtime electronic waveforms fed to a multi-channel digitizer on a PC platform. The digitizer consists of one or more National Instruments Corp. AMUX–64T multiplexer boards attached to an A/D converter board located in the computer. Originally, passive filters were installed on the multiplexers to eliminate electronic noise picked up in cabling. It was later discovered that a small amount of crosstalk occurred between successive channels in the digitizing sequence. Though small, this crosstalk will cause what appear to be small earthquake arrivals at the wrong time on some channels. This can result in erroneous calculation of earthquake arrival times, particularly by automated algorithms. To deal with this problem, an Earthworm filter board was developed to provide the needed filtering while eliminating crosstalk. This report describes the tests performed to find a suitable solution, and the design of the circuit board. Also included are all the details needed to build and install this board in an Earthworm system or any other system using the AMUX–64T board. Available below is the report in PDF format as well as an archive file containing the circuit board manufacturing information.

  3. Application of microcosmic system for assessment of insecticide effects on biomarker responses in ecologically different earthworm species.

    PubMed

    Velki, Mirna; Hackenberger, Branimir K; Lon?ari?, Zeljka; Hackenberger, Davorka K

    2014-06-01

    Earthworms from different ecological categories--epigeic Eisenia andrei and Lumbricus rubellus, endogeic Octolasion lacteum and anecic Lumbricus terrestris--were exposed in a microcosmic system to three commonly used insecticides. The effects of the insecticides were evaluated by measuring the following molecular biomarkers-the activities of AChE, CES, CAT, GST and the concentration of GSH. The results showed that environmentally relevant doses of organophosphates dimethoate and pirimiphos-methyl significantly affected the measured biomarkers, whereas pyrethroid deltamethrin did not affect the earthworms at the recommended agricultural dose. Considering the ecological category of earthworms, the results were inhomogeneous and species-specific differences in the biomarker responses were recorded. Since the biomarker responses of the investigated earthworm species were different after exposure to organophosphates in a microcosm compared to the exposure via standardized toxicity tests, two types of species sensitivity should be distinguished-physiological and environmental sensitivity. In addition, the hormetic effect of organophosphates on AChE and CES activities was recorded. The detection of hormesis in a microcosm is of great importance for future environmental research and soil biomonitoring, since in a realistic environment pollutants usually occur at low concentrations that could cause a hormetic effect. The results demonstrate the importance of the application of microcosmic systems in the assessment of the effects of environmental pollutants and the necessity of taking into account the possible differences between physiological and environmental species sensitivity. PMID:24650551

  4. Earthworms Produce phytochelatins in Response to Arsenic

    PubMed Central

    Lawlor, Alan J.; Bennett, Mark H.; Morris, Ceri A.; Kille, Peter; Svendsen, Claus; Spurgeon, David J.; Bundy, Jacob G.

    2013-01-01

    Phytochelatins are small cysteine-rich non-ribosomal peptides that chelate soft metal and metalloid ions, such as cadmium and arsenic. They are widely produced by plants and microbes; phytochelatin synthase genes are also present in animal species from several different phyla, but there is still little known about whether these genes are functional in animals, and if so, whether they are metal-responsive. We analysed phytochelatin production by direct chemical analysis in Lumbricus rubellus earthworms exposed to arsenic for a 28 day period, and found that arsenic clearly induced phytochelatin production in a dose-dependent manner. It was necessary to measure the phytochelatin metabolite concentrations directly, as there was no upregulation of phytochelatin synthase gene expression after 28 days: phytochelatin synthesis appears not to be transcriptionally regulated in animals. A further untargetted metabolomic analysis also found changes in metabolites associated with the transsulfuration pathway, which channels sulfur flux from methionine for phytochelatin synthesis. There was no evidence of biological transformation of arsenic (e.g. into methylated species) as a result of laboratory arsenic exposure. Finally, we compared wild populations of earthworms sampled from the field, and found that both arsenic-contaminated and cadmium-contaminated mine site worms had elevated phytochelatin concentrations. PMID:24278409

  5. Metals and terrestrial earthworms (Annelida: Oligochaeta)

    USGS Publications Warehouse

    Beyer, W.N.

    1981-01-01

    The toxicity of metals to earthworms and the residues of metals found in earthworms are reviewed. Meta 1 concentrations are rarely high enough to be toxic to worms, but copper may reduce populations in orchards heavily treated with fungicides and in soil contaminated with pig wastes. The metals in some industrial sewage sludges may interfere with using sludge in vermiculture. Storage ratios (the concentration of a metal in worms divided by the concentration in soil) tend to be highest in infertile soil and lowest in media rich in organic matter, such as sewage sludge. Cadmium, gold, and selenium are highly concentrated by worms. Lead concentrations in worms may be very high, but are generally lower than concentrations in soil. Body burdens of both copper and zinc seem to be regulated by worms. Because worms are part of the food webs of many wildlife species, and also because they are potentially valuable feed supplements for domestic animals, the possible toxic effects of cadmium and other metals should be studied. Worms can make metals more available to food webs and can redistribute them in soil.

  6. Analysis of Eisenia fetida earthworm responses to sub-lethal C60 nanoparticle exposure using (1)H-NMR based metabolomics.

    PubMed

    Lankadurai, Brian P; Nagato, Edward G; Simpson, André J; Simpson, Myrna J

    2015-10-01

    The enhanced production and environmental release of Buckminsterfullerene (C60) nanoparticles will likely increase the exposure and risk to soil dwelling organisms. We used (1)H NMR-based metabolomics to investigate the response of Eisenia fetida earthworms to sub-lethal C60 nanoparticle exposure in both contact and soil tests. Principal component analysis of (1)H NMR data showed clear separation between controls and exposed earthworms after just 2 days of exposure, however as exposure time increased the separation decreased in soil but increased in contact tests suggesting potential adaptation during soil exposure. The amino acids leucine, valine, isoleucine and phenylalanine, the nucleoside inosine, and the sugars glucose and maltose emerged as potential bioindicators of exposure to C60 nanoparticles. The significant responses observed in earthworms using NMR-based metabolomics after exposure to very low concentrations of C60 nanoparticles suggests the need for further investigations to better understand and predict their sub-lethal toxicity. PMID:26024814

  7. EPR detection of hydroxyl radical generation and oxidative perturbations in lead-exposed earthworms (Eisenia fetida) in the presence of decabromodiphenyl ether.

    PubMed

    Liu, Kou; Chen, Lin; Zhang, Wei; Lin, Kuangfei; Zhao, Li

    2015-03-01

    Lead (Pb) and decabromodiphenyl ether (BDE209) are the main contaminants at e-waste recycling sites, and their potential toxicological effects on terrestrial organisms have received extensive attention. However, the impacts on the oxidative perturbations and hydroxyl radical (·OH) generation in earthworms of exposure to the two chemicals remain almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the effects of Pb in earthworms Eisenia fetida in the presence of BDE209 through the use of several biomarkers in microcosms. The results have demonstrated that the addition of BDE209 (1 or 10 mg kg(-1)) decreased the enzymatic activities [superoxide dismutase, catalase (CAT), peroxidase] and total antioxidant capacity (T-AOC) compared with exposure to BDE209 alone (50, 250 or 500 mg kg(-1)). Electron paramagnetic resonance spectra indicated that ·OH radicals in earthworms were significantly induced by Pb in the presence of BDE209. The changing pattern of malondialdehyde (MDA) contents was accordant with that of ·OH intensity suggested that reactive oxygen species might lead to cellular lipid peroxidation. Furthermore, CAT exhibited more sensitive response to single Pb exposure than the other biomarkers, while T-AOC, ·OH and MDA might be three most sensitive biomarkers in earthworms after simultaneous exposure to Pb and BDE209. The results of these observations suggested that oxidative stress appeared in E. fetida, and it may play an important role in inducing the Pb and BDE209 toxicity to earthworms. PMID:25373545

  8. 1H NMR Metabolomics: A New Molecular Level Tool for Assessment of Organic Contaminant Bioavailability to Earthworms in Soil

    NASA Astrophysics Data System (ADS)

    McKelvie, J. R.; Wolfe, D. M.; Celejewski, M. A.; Simpson, A. J.; Simpson, M. J.

    2009-05-01

    At contaminated field sites, the complete removal of polycyclic aromatic hydrocarbons (PAHs) is rarely achieved since a portion of these compounds remain tightly bound to the soil matrix. The concentration of PAHs in soil typically decreases until a plateau is reached, at which point the remaining contaminant is considered non- bioavailable. Numerous soil extraction techniques, including cyclodextrin extraction, have been developed to estimate contaminant bioavailability. However, these are indirect methods that do not directly measure the response of organisms to chemical exposure in soil. Earthworm metabolomics offers a promising new way to directly evaluate the bioavailability and toxicity of contaminants in soil. Metabolomics involves the measurement of changes in small-molecule metabolites, including sugars and amino acids, in living organisms due to an external stress, such as contaminant exposure. The objective of this study was to compare cyclodextrin extraction of soil (a bioavailability proxy) and 1H NMR metabolomic analysis of aqueous earthworm tissue extracts as indicators of contaminant bioavailability. A 30 day laboratory experiment was conducted using phenanthrene-spiked sphagnum peat soil and the OECD recommended earthworm species for toxicity testing, Eisenia fetida. The initial phenanthrene concentration in the soil was 320 mg/kg. Rapid biodegradation of phenanthrene occurred and concentrations decreased to 16 mg/kg within 15 days. After 15 days, phenanthrene biodegradation slowed and cyclodextrin extraction of the soil suggested that phenanthrene was no longer bioavailable. Multivariate statistical analysis of the 1H NMR spectra for E. fetida tissue extracts indicated that the metabolic profile of phenanthrene exposed earthworms differed from control earthworms throughout the 30 day experiment. This suggests that the residual phenanthrene remaining in the soil after 15 days continued to elicit a metabolic response, even though it was not extractable using cyclodextrin. Hence, while cyclodextrin extraction may serve as a good proxy for microbial bioavailability, our results suggest that it may not serve as a good proxy for earthworm bioavailability. 1H NMR metabolomics therefore offers considerable promise as a novel, molecular-level method to directly monitor earthworm bioavailability of potentially toxic and persistent compounds in the environment.

  9. Shade Avoidance

    PubMed Central

    Casal, Jorge J.

    2012-01-01

    The presence of neighboring vegetation modifies the light environment experienced by plants, generating signals that are perceived by phytochromes and cryptochromes. These signals cause large changes in plant body form and function, including enhanced growth of the hypocotyl and petioles, a more erect position of the leaves and early flowering in Arabidopsis thaliana. Collectively, these so-called shade-avoidance responses tend to reduce the degree of current or future shade by neighbors. Shade light signals increase the abundance of PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and PIF5 proteins, promote the synthesis and redirection of auxin, favor the degradation of DELLA proteins and increase the expression of auxin, gibberellins and brassinosteroid-promoted genes, among other events downstream the photoreceptors. Selectively disrupting these events by genetic or pharmacological approaches affects shade-avoidance responses with an intensity that depends on the developmental context and the environment. Shade-avoidance responses provide a model to investigate the signaling networks used by plants to take advantage of the cues provided by the environment to adjust to the challenges imposed by the environment itself. PMID:22582029

  10. Toxicity and bioaccumulation of ethofumesate enantiomers in earthworm Eisenia fetida.

    PubMed

    Xu, Peng; Wang, Yinghuan; Zhang, Yanfeng; Li, Jianzhong; Wang, Huili

    2014-10-01

    Earthworms represent an important food source for many vertebrates and as a result, predators may encounter toxic effects via the food chain from consumption of contaminated worms. Therefore, including an assessment of xenobiotic to worms in risk assessment procedures is advisable. Here we studied the acute toxicity, bioaccumulation and elimination of ethofumesate enantiomers in earthworm, Eisenia fetida, in a soil. A slight difference in toxicity to earthworm between two enantiomers was found, and the calculated LC50 values for (+)-, rac- and (-)-ethofumesate were 4.51, 5.93 and 7.98 ?g/cm(2), respectively, indicating that the acute toxicity of ethofumesate enantiomers was enantioselective. Earthworm can uptake ethofumesate but the bioaccumulation curve did not reach the steady state. In the elimination experiment, the concentrations of ethofumesate in earthworm declined following a first-order decay model with a short half life of 1.8d. The bioaccumulation and elimination of ethofumesate in earthworm were both nonenantioselective. In combination with other studies, a linear relationship between Log BSAFs and Log Kow was observed, and the Log BSAFs increased with increasing Log Kow. But the elimination rate did not show any correlation with the Kow value. PMID:25048902

  11. Toxicity and bioaccumulation of bromadiolone to earthworm Eisenia fetida.

    PubMed

    Liu, Jing; Xiong, Kang; Ye, Xiaoqing; Zhang, Jianyun; Yang, Ye; Ji, Li

    2015-09-01

    Bromadiolone, a potent second-generation anticoagulant rodenticide, has been extensively used worldwide for the field control of rodents. Invertebrates may be at risk from primary poisoning as a result of bromadiolone bait applications. However, there are few data regarding the toxicity and bioaccumulation of bromadiolone to earthworms. In this study, we reported that bromadiolone was toxic to earthworms at 1mg/kg soil, which is a likely concentration in the field following application of bromadiolone baits. Exposure to bromadiolone resulted in a significant inhibition of earthworm growth. The antioxidant activities of superoxide dismutase and catalase were slightly increased in earthworms, while malondialdehyde content (as a molecular marker indicative of the damage to lipid peroxidation) was dominantly elevated over the duration of exposure. Bromadiolone in soil is bioaccumulative to earthworms. The biota to soil accumulation factors (BSAFs) of bromadiolone were concentration dependent and BSAFs decreased as the level of bromadiolone in soil increased. These results suggest earthworms are not only the potential subject to primary poisoning but also the source of secondary exposure for insectivores and scavengers following application of bromadiolone. PMID:25965004

  12. Gene Expression Analysis of CL-20-induced Reversible Neurotoxicity Reveals GABAA Receptors as Potential Target in the Earthworm Eisenia fetida

    PubMed Central

    Gong, Ping; Guan, Xin; Pirooznia, Mehdi; Liang, Chun; Perkins, Edward J.

    2012-01-01

    The earthworm Eisenia fetida is one of the most used species in standardized soil ecotoxicity tests. Endpoints such as survival, growth and reproduction are eco-toxicologically relevant but provide little mechanistic insight into toxicity pathways, especially at the molecular level. Here we applied a toxicogenomic approach to investigate the mode of action underlying the reversible neurotoxicity of hexanitrohexaazaisowurtzitane (CL-20), a cyclic nitroamine explosives compound. We developed an E. fetida-specific shotgun microarray targeting 15119 unique E. fetida transcripts. Using this array we profiled gene expression in E. fetida in response to exposure to CL-20. Eighteen earthworms were exposed for 6 days to 0.2 ?g/cm2 of CL-20 on filter paper, half of which were allowed to recover in a clean environment for 7 days. Nine vehicle control earthworms were sacrificed at day 6 and 13, separately. Electrophysiological measurements indicated that the conduction velocity of earthworm medial giant nerve fiber decreased significantly after 6-day exposure to CL-20, but was restored after 7 days of recovery. Total RNA was isolated from the four treatment groups including 6-day control, 6-day exposed, 13-day control and 13-day exposed (i.e. 6-day exposure followed by 7-day recovery), and was hybridized to the 15K shot-gun oligo array. Statistical and bioinformatic analyses suggest that CL-20 initiated neurotoxicity by non-competitively blocking the ligand-gated GABAA receptor ion channel, leading to altered expression of genes involved in GABAergic, cholinergic, and Agrin-MuSK pathways. In the recovery phase, expression of affected genes returned to normality, possibly as a result of autophagy and CL-20 dissociation/metabolism. This study provides significant insights into potential mechanisms of CL-20-induced neurotoxicity and the recovery of earthworms from transient neurotoxicity stress. PMID:22191394

  13. Test anxiety and performance-avoidance goals explain gender differences in SAT-V, SAT-M, and overall SAT scores

    PubMed Central

    Hannon, Brenda

    2013-01-01

    This study uses analysis of co-variance in order to determine which cognitive/learning (working memory, knowledge integration, epistemic belief of learning) or social/personality factors (test anxiety, performance-avoidance goals) might account for gender differences in SAT-V, SAT-M, and overall SAT scores. The results revealed that none of the cognitive/learning factors accounted for gender differences in SAT performance. However, the social/personality factors of test anxiety and performance-avoidance goals each separately accounted for all of the significant gender differences in SAT-V, SAT-M, and overall SAT performance. Furthermore, when the influences of both of these factors were statistically removed simultaneously, all non-significant gender differences reduced further to become trivial by Cohen's (1988) standards. Taken as a whole, these results suggest that gender differences in SAT-V, SAT-M, and overall SAT performance are a consequence of social/learning factors. PMID:23997382

  14. Construction of an electrical device for sampling earthworm populations in the field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Well-known methods for estimating earthworm population densities range from laborious handsorting through chemical applications to electrical extraction. Of these methods, only the electrical extraction allows for sampling of earthworms without detrimental soil disturbance or contamination. However,...

  15. Acute toxicity of multi-walled carbon nanotubes, sodium pentachlorophenate, and their complex on earthworm Eisenia fetida.

    PubMed

    Zhang, Liujun; Hu, Changwei; Wang, Weili; Ji, Funian; Cui, Yibin; Li, Mei

    2014-05-01

    Laboratory experiments were undertaken to relate biomarker responses to the toxicities of multi-walled carbon nanotubes (MWCNTs) and sodium pentachlorophenate (PCP-Na), both individually and combined. The acute toxicities of MWCNTs and PCP-Na on earthworm Eisenia fetida were studied through different exposure methods (filter paper contact test, immersion contact test, and artificial soil contact test). Enzyme activity and malondialdehyde (MDA) content in the earthworm E. fetida exposed to MWCNTs and PCP-Na in filter paper contact test, both individually and under combined exposure, were determined. After exposure, PCP-Na induced observable acute toxicity while the MWCNTs induced slight toxicity. Interestingly the earthworms exposed to the mixture of MWCNTs and PCP-Na demonstrated different expression of enzymatic biomarkers from those exposed to MWCNTs or PCP-Na alone. Our results indicated that the toxicity of PCP-Na on E. fetida may be alleviated by the appearance of MWCNTs for all exposure methods except for immersion contact test. PMID:24562180

  16. Influence of temperature on the toxicity of zinc to the earthworm Eisenia fetida

    SciTech Connect

    Spurgeon, D.J.; Tomlin, M.A.; Hopkin, S.P. [Univ. of Reading (United Kingdom)] [Univ. of Reading (United Kingdom)

    1997-02-01

    A range of toxicity tests have been proposed to assess the potential hazards of pollutants to earthworms. Of these, the two acute toxicity tests using Eisenia fetida recommended by the OECD and EEC have become routinely used in the risk assessment and regulation of new and existing chemicals. In addition to the acute tests, procedures have also been proposed for measuring the sub-lethal effects of chemicals on parameter such as reproduction and weight change. In both the lethal and sub-lethal toxicity tests developed with worms, attempts have been made to standardise test conditions to allow results from different laboratories to be directly compared. However, variability in exposure conditions and responses are fundamental to determine the effects of pollutants under natural conditions. In the field, conditions such as light, moisture availability, pH, temperature and humidity all fluctuate over time. Such variations affect both the sensitivity and exposure of individuals to toxic chemicals. Hence when evaluating the potential effects of pollutants, it may be important to known how changes in test conditions influence toxicity. This study assessed the effects of different temperatures on the lethal and sub-lethal toxicity of zinc for the earthworm Eisenia fetida. 23 refs., 1 fig., 1 tab.

  17. Associations between soil texture, soil water characteristics and earthworm populations in grassland

    Microsoft Academic Search

    Martin Holmstrup; Mathieu Lamandé; Sřren B. Torp; Mogens H. Greve; Rodrigo Labouriau; Goswin Heckrath

    2011-01-01

    The aim of the present study was to investigate the relationships between soil physical characteristics and earthworms in a regional-scale field study in Denmark. The earthworm populations along within-field gradients in soil texture were quantified at five field sites, representing dominant soil types of Denmark. Eleven earthworm species were found, but populations were mainly dominated by Aporrectodea tuberculata and A.

  18. Earthworm Ecology in the Northern Part of Iran: With an Emphasis on Compost Worm Eisenia fetida

    Microsoft Academic Search

    G. A. Omrani; M. Zamanzadeh; A. Maleki; Y. Ashori

    2005-01-01

    In the present study, Northern part of Iran was chosen as study area. Four hundred samples of earthworms were collected by three methods (hand-sorting, chemical and heat extraction) of which 352 and 20 were mature and immature earthworms, respectively from different parts of the area. Following the method introduced by Graff the earthworms were placed in formaldehyde (5 and 10%)

  19. Earthworm and belowground competition effects on plant productivity in a plant diversity gradient

    Microsoft Academic Search

    Nico Eisenhauer; Alexandru Milcu; Norma Nitschke; Alexander C. W. Sabais; Christoph Scherber; Stefan Scheu

    2009-01-01

    Diversity is one major factor driving plant productivity in temperate grasslands. Although decomposers like earthworms are known to affect plant productivity, interacting effects of plant diversity and earthworms on plant productivity have been neglected in field studies. We investigated in the field the effects of earthworms on plant productivity, their interaction with plant species and functional group richness, and their

  20. EARTHWORMS AND COLLEMBOLA RELATIONSHIPS: EFFECTS2 OF PREDATORY CENTIPEDES AND HUMUS FORMS3

    E-print Network

    Boyer, Edmond

    1 EARTHWORMS AND COLLEMBOLA RELATIONSHIPS: EFFECTS2 OF PREDATORY CENTIPEDES AND HUMUS FORMS3 4 macroporosity, improve the escape routes for18 Collembola and thus evade predators. In moder humus earthworms (1) the positive effect of earthworms in moder was observed only on larger24 Collembola (> 1 mm), (2

  1. INVASION NOTE The wave towards a new steady state: effects of earthworm

    E-print Network

    Minnesota, University of

    INVASION NOTE The wave towards a new steady state: effects of earthworm invasion on soil microbial. However, the consequences of earthworm invasion for soil microbial functions are poorly understood. Here previously. Soil microbial biomass, respiration and metabolic quotient were measured. Earthworms had marked

  2. Toxicity of mixtures of ?-cyhalothrin, imidacloprid and cadmium on the earthworm Eisenia fetida by combination index (CI)-isobologram method.

    PubMed

    Wang, Yanhua; Chen, Chen; Qian, Yongzhong; Zhao, Xueping; Wang, Qiang; Kong, Xiangzhen

    2015-01-01

    Contaminants in the environment do not appear singly and usually occur as mixtures. We applied the combination index (CI)-isobologram method which allows computerized quantitation of synergism, additive effect and antagonism to determine the nature of toxicological interactions of two pesticides ?-cyhalothrin, imidacloprid, and heavy metal cadmium towards earthworm Eisenia fetida. In an artificial soil test, ?-cyhalothrin and Cd combination was slightly synergistic at low effect levels which turned into a slight antagonism above f(a) values of 0.6, while the binary mixtures containing imidacloprid exhibited antagonism. The presence of imidacloprid in the ternary mixture also resulted in an antagonistic effect to the earthworms. This behavior became more antagonistic in the ternary mixture in filter paper tests. PMID:25450940

  3. Conditioned suppression/avoidance as a procedure for testing hearing in birds: the domestic pigeon (Columba livia).

    PubMed

    Heffner, Henry E; Koay, Gimseong; Hill, Evan M; Heffner, Rickye S

    2013-06-01

    Although the domestic pigeon is commonly used in learning experiments, it is a notoriously difficult subject in auditory psychophysical experiments, even those in which it need only respond when it detects a sound. This is because pigeons tend to respond in the absence of sound-that is, they have a high false-positive rate-which makes it difficult to determine a pigeon's audiogram. However, false positives are easily controlled in the method of conditioned suppression/avoidance, in which a pigeon is trained to peck a key to obtain food and to stop pecking whenever it detects a sound that signals impending electric shock. Here, we describe how to determine psychophysical thresholds in pigeons using a method of conditioned suppression in which avoidable shock is delivered through a bead chain wrapped around the base of a pigeon's wings. The resulting audiogram spans the range from 2 to 8000 Hz; it falls approximately in the middle of the distribution of previous pigeon audiograms and supports the finding of Kreithen and Quine (Journal of Comparative Physiology 129:1-4, 1979) that pigeons hear infrasound. PMID:23055174

  4. A new and sensitive method for measuring in vivo and in vitro cytotoxicity in earthworm coelomocytes by flow cytometry.

    PubMed

    Kwak, Jin Il; Kim, Shin Woong; An, Youn-Joo

    2014-10-01

    This study describes a new and sensitive method for measuring the in vivo and in vitro cytotoxicity of 2 earthworm species, Eisenia andrei and Perionyx excavatus, exposed to copper. Specifically, we measured the number of coelomocyte cells that were affected by copper following in vivo and in vitro exposure by flow cytometry, after calcein acetoxymethyl ester (calcein-AM) staining. We found that the coelomocyte viability of both earthworm species was noticeably reduced in the in vivo cytotoxicity test at concentrations of 100mg/kg copper in dry soil. However, pathological symptoms, such as mucous secretion and bleeding, swelling, thinning, and fragmentation, and burrowing symptoms were not evident following exposure to copper levels of <400mg/kg dry soil. In conclusion, the present study demonstrates that calcein-AM is a more sensitive test of earthworm coelomocyte cytotoxicity compared to the traditional individual level toxicity test. Therefore, this test could be used to detect low levels of metal contamination in soils. PMID:25127522

  5. Comparative toxicity of pentachlorophenol to three earthworm species in artificial soil

    SciTech Connect

    Fitzgerald, D.; Lanno, R.P.; Farwell, A.; Dixon, D.G. [Univ. of Waterloo, Ontario (Canada). Dept. of Biology

    1994-12-31

    Although methods for standardized toxicity tests with earthworms exist, many of the test parameters and conditions have not been validated in actual tests and with different species of worms. This study evaluated the toxicity of pentachlorophenol (PCP) to three species of earthworms, Lumbricus terrestris, Eisenia fetida, and Eudrilus eugeniae using various methods of data analysis and body residues. Tests were conducted in artificial soil for a period of 28 days or until an Acute Lethality Threshold (ALT) was reached. An intensive temporal sampling regime was applied to generate sufficient data for the accurate estimation of ALTs using both LC50/time and time-to-death/soil concentration methods of data analysis. L. terrestris was tested at 15 C, E. eugeniae at 24 C, and E. fetida at both temperatures. Total body residues of PCP were measured by GC following cryogenic separation of the lipid fraction of the worm. ALTs were significantly different between E. fetida and the two larger species of worms. No effect of temperature on the ALT for E. fetida was observed, although the time taken to reach the ALT increased at the lower temperature. The relationship of PCP residues at mortality will be discussed in terms of the effects of species, body size and temperature. Limitations of the artificial soil based upon growth curves of worms will also be examined.

  6. Toxicity of sodium tungstate to earthworm, oat, radish, and lettuce.

    PubMed

    Bamford, Josie E; Butler, Alicia D; Heim, Katherine E; Pittinger, Charles A; Lemus, Ranulfo; Staveley, Jane P; Lee, K Brian; Venezia, Carmen; Pardus, Michael J

    2011-10-01

    Due to unknown effects of the potential exposure of the terrestrial environment to tungsten substances, a series of toxicity studies of sodium tungstate (Na(2) WO(4) ) was conducted. The effect on earthworm (Eisenia fetida) survival and reproduction was examined using Organisation for Economic Co-operation and Development (OECD) Guideline 222. No effect on either endpoint was seen at the highest concentration tested, resulting in a 56-d no-observed-effect concentration (NOEC) of ?586 mg tungsten/kg dry soil (nominal concentrations). The effect of sodium tungstate on emergence and growth of plant species was examined according to OECD Guideline 208: oat (Avena sativa), radish (Raphanus sativus), and lettuce (Lactuca sativa). No effects on emergence, shoot height, and dry shoot weight were observed in oats exposed to the highest concentration, resulting in a 21-d NOEC of ?586 mg tungsten/kg dry soil. The NOECs for radish and lettuce were 65 and 21.7 mg tungsten/kg dry soil (nominal concentrations), respectively. Respective 21-d median effective concentration values (EC50) for radish and lettuce were >586 and 313 mg tungsten/kg dry soil (based on shoot height) (confidence level [CL] -8.5-615); EC25 values were 152 (CL 0-331) and 55 (CL 0-114) mg tungsten/kg dry soil. Results are consistent with the few other tungsten substance terrestrial toxicity studies in the literature. PMID:21805499

  7. Fate and Uptake of Pharmaceuticals in Soil–Earthworm Systems

    PubMed Central

    2014-01-01

    Pharmaceuticals present a potential threat to soil organisms, yet our understanding of their fate and uptake in soil systems is limited. This study therefore investigated the fate and uptake of 14C-labeled carbamazepine, diclofenac, fluoxetine, and orlistat in soil–earthworm systems. Sorption coefficients increased in the order of carbamazepine < diclofenac < fluoxetine < orlistat. Dissipation of 14C varied by compound, and for orlistat, there was evidence of formation of nonextractable residues. Uptake of 14C was seen for all compounds. Depuration studies showed complete elimination of 14C for carbamazepine and fluoxetine treatments and partial elimination for orlistat and diclofenac, with greater than 30% of the 14C remaining in the tissue at the end of the experiment. Pore-water-based bioconcentration factors (BCFs), based on uptake and elimination of 14C, increased in the order carbamazepine < diclofenac < fluoxetine and orlistat. Liquid chromatography–tandem mass spectrometry and liquid chromatography–Fourier transform mass spectrometry indicated that the observed uptake in the fluoxetine and carbamazepine treatments was due to the parent compounds but that diclofenac was degraded in the test system so uptake was due to unidentifiable transformation products. Comparison of our data with outputs of quantitative structure?activity relationships for estimating BCFs in worms showed that these models tend to overestimate pharmaceutical BCFs so new models are needed. PMID:24762061

  8. Ecotoxicity of silver nanoparticles on earthworm Eisenia fetida: responses of the antioxidant system, acid phosphatase and ATPase

    Microsoft Academic Search

    Changwei Hu; Mei Li; Weili Wang; Yibin Cui; Jun Chen; Liuyan Yang

    2012-01-01

    Ecotoxicity of nanoparticles has received growing attention in recent years. This study investigated the influence of silver nanoparticles (Ag-NP) on earthworm Eisenia fetida. The experiment was performed with five test groups: control (without Ag-NP), 10?nm Ag-NP groups (20, 100 or 500?mg?kg) and positive control (787?mg?kg AgNO3). After 14-day acute exposure, activities of various enzymes, including glutathione S-transferase (GST), glutathione reductase

  9. Existential Threat or Dissociative Response? Examining Defensive Avoidance of Point-of-Care Testing Devices Through a Terror Management Theory Framework.

    PubMed

    Dunne, Simon; Gallagher, Pamela; Matthews, Anne

    2015-01-01

    Using a terror management theory framework, this study investigated if providing mortality reminders or self-esteem threats would lead participants to exhibit avoidant responses toward a point-of-care testing device for cardiovascular disease risk and if the nature of the device served to diminish the existential threat of cardiovascular disease. One hundred and twelve participants aged 40-55 years completed an experimental questionnaire. Findings indicated that participants were not existentially threatened by established terror management methodologies, potentially because of cross-cultural variability toward such methodologies. Highly positive appraisals of the device also suggest that similar technologies may beneficially affect the uptake of screening behaviors. PMID:24972015

  10. Methylation of mercury in earthworms and the effect of mercury on the associated bacterial communities.

    PubMed

    Rieder, Stephan Raphael; Brunner, Ivano; Daniel, Otto; Liu, Bian; Frey, Beat

    2013-01-01

    Methylmercury compounds are very toxic for most organisms. Here, we investigated the potential of earthworms to methylate inorganic-Hg. We hypothesized that the anaerobic and nutrient-rich conditions in the digestive tracts of earthworm's promote the methylation of Hg through the action of their gut bacteria. Earthworms were either grown in sterile soils treated with an inorganic (HgCl2) or organic (CH3HgCl) Hg source, or were left untreated. After 30 days of incubation, the total-Hg and methyl-Hg concentrations in the soils, earthworms, and their casts were analyzed. The impact of Hg on the bacterial community compositions in earthworms was also studied. Tissue concentrations of methyl-Hg in earthworms grown in soils treated with inorganic-Hg were about six times higher than in earthworms grown in soils without Hg. Concentrations of methyl-Hg in the soils and earthworm casts remained at significantly lower levels suggesting that Hg was mainly methylated in the earthworms. Bacterial communities in earthworms were mostly affected by methyl-Hg treatment. Terminal-restriction fragments (T-RFs) affiliated to Firmicutes were sensitive to inorganic and methyl-Hg, whereas T-RFs related to Betaproteobacteria were tolerant to the Hg treatments. Sulphate-reducing bacteria were detected in earthworms but not in soils. PMID:23577209

  11. Collision Avoidance System

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Ames Research Center teamed with the Federal Aviation Administration (FAA) to study human performance factors associated with the use of the Traffic Alert and Collision Avoidance system (TCAS II) in an operational environment. TCAS is designed to alert pilots of the presence of other aircraft in their vicinity, to identify and track those who could be a threat, and to recommend action to avoid a collision. Ames conducted three laboratory experiments. The first showed that pilots were able to use the TCAS II correctly in the allowable time. The second tested pilots' response to changes in the avoidance advisories, and the third examined pilots' reactions to alternative displays. After a 1989 congressional mandate, the FAA ruled that TCAS would be required on all passenger carrying aircraft (to be phased in completely by 1995).

  12. Interactions between the nematode parasite of pigs, Ascaris suum, and the earthworm Aporrectodea longa.

    PubMed

    Kraglund, H O; Grřnvold, J; Roepstorff, A; Rawat, H

    1998-01-01

    Pig faeces in which Ascaris suum eggs had been embryonating for 57 days were placed in buckets of soil containing either 30 or no earth-worms (Aporrectodea longa). When present, earthworms consumed the faeces and transported the eggs down into the soil, without inflicting any visible damage on the eggs. In later experiments 10 earthworms from the above experiment were fed to each of ten pigs, and another 40 earthworms were dissected. None of the 10 pigs became infected with A. suum through consumption of earthworms, and none of the dissected earthworms were found to contain A. suum larvae. This experiment indicates that A. longa did not act as a paratenic host for A. suum but shows that earthworms are very efficient in transporting A. suum eggs from faeces deposited on the soil surface into the soil. PMID:9926459

  13. Impact of Parthenium weeds on earthworms (Eudrilus eugeniae) during vermicomposting.

    PubMed

    Rajiv, P; Rajeshwari, Sivaraj; Rajendran, Venckatesh

    2014-11-01

    The aim of this work is to evaluate the effect of Parthenium-mediated compost on Eudrilus eugeniae during the process of vermicomposting. Nine different concentrations of Parthenium hysterophorus and cow dung mixtures were used to assess toxicity. The earthworms' growth, fecundity and antioxidant enzyme levels were analysed every 15 days. The antioxidant activities of enzymes [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)], considered as biomarkers, indicate the biochemical and oxidative stresses due to the toxin from Parthenium weeds. The earthworms' growth, biomass gain, cocoon production and antioxidant enzymes were in a low level in a high concentration of P. hysterophorus (without cow dung). The results clearly indicated that appropriate mixing of P. hysterophorus quantity is an essential factor for the survival of earthworms without causing any harm. PMID:24938809

  14. Recombinant Protein Production of Earthworm Lumbrokinase for Potential Antithrombotic Application

    PubMed Central

    Wang, Kevin Yueju; Wang, Nan; Liu, Dehu

    2013-01-01

    Earthworms have been used as a traditional medicine in China, Japan, and other Far East countries for thousands of years. Oral administration of dry earthworm powder is considered as a potent and effective supplement for supporting healthy blood circulation. Lumbrokinases are a group of enzymes that were isolated and purified from different species of earthworms. These enzymes are recognized as fibrinolytic agents that can be used to treat various conditions associated with thrombosis. Many lumbrokinase (LK) genes have been cloned and characterized. Advances in genetic technology have provided the ability to produce recombinant LK and have made it feasible to purify a single lumbrokinase enzyme for potential antithrombotic application. In this review, we focus on expression systems that can be used for lumbrokinase production. In particular, the advantages of using a transgenic plant system to produce edible lumbrokinase are described. PMID:24416067

  15. Bioavailability of nonextractable (bound) pesticide residues to earthworms.

    PubMed

    Gevao, B; Mordaunt, C; Semple, K T; Piearce, T G; Jones, K C

    2001-02-01

    There is an ongoing debate regarding whether nonextractable (bound) pesticide residues in soils are occluded or may remain bioavailable in the long term in the environment. This study investigated the release of 14C-labeled residues, which were previously nonextractable after exhaustive extraction with organic solvents in soils, and their uptake by earthworms (Aporrectodea longa). After a 100-day incubation of soils treated with 14C-labeled atrazine, isoproturon, and dicamba and exhaustive Soxhlet extractions with methanol and dichloromethane, nonextracted 14C-labeled residues remaining in the soils were 18, 70, and 67%, respectively. Adding clean soil in the ratio of 7:1 increased the volumes of these extracted soils. After earthworms had lived in these previously extracted soils for 28 days, 0.02-0.2% of previously bound 14C activity was absorbed into the earthworm tissue. Uptake by earthworms was found to be 2-10 times higher in soils containing freshly introduced 14C-labeled pesticides as compared to soils containing nonextractable 14C-labeled residues. The differential bioavailability observed between freshly introduced 14C-labeled pesticides and those previously nonextractable may be related to the ease of transfer of the 14C activity into the solution phase. By the end of the 28-day incubation period, 3, 23, and 24% of previously nonextractable 14C-labeled isoproturon, dicamba, and atrazine residues, respectively, were extracted by solvents or mineralized to 14CO2. The amounts of 14C activity released were not significantly different in the presence or in the absence of earthworms in soils containing previously nonextractable residues. However, the formation of bound residues was 2, 2, and 4 times lower for freshly introduced 14C-labeled isoproturon, dicamba, and atrazine, respectively, suggesting that the presence of earthworms retarded bound residue formation. PMID:11351720

  16. Accumulation of chlorinated benzenes in earthworms

    SciTech Connect

    Beyer, W.N. [Patuxent Wildlife Research Center, Laurel, MD (United States)] [Patuxent Wildlife Research Center, Laurel, MD (United States)

    1996-12-31

    Chlorinated benzenes are widespread in the environment. Hexachlorobenzene, pentachlorobenzene and all isomers of dichlorobenzenes, trichlorobenzenes, and tetrachlorobenzenes, have been detected in fish, water, and sediments from the Great Lakes. They probably entered the water as leachates from chemical waste dumps and as effluents from manufacturing. Hexachlorobenzene and pentachlorobenzene are commonly present in Herring gull (Larus argentatus) eggs from the Great Lakes, and some of the isomers of trichlorobenzene and tetrachlorobenzene are occasionally detected at low concentrations. Hexachlorobenzene, which was formerly used as a fungicide, has been the most thoroughly studied chlorinated benzene, and has been detected in many species. Its use as a fungicide in the United States was canceled in 1984. Since about 1975 hexachlorobenzene has been formed mainly in the production of chlorinated solvents. It is highly persistent in the environment and some species are poisoned by hexachlorobenzene at very low chronic dietary exposures. As little as 1 ppm in the diet of mink (Mustela vison) reduced the birth weights of young, and 5 ppm in the diet of Japanese quail (Coturnix coturnix japonica) caused slight liver damage. This paper describes a long-term (26 wk) experiment relating the concentrations of chlorinated benzenes in earthworms to length of exposure and three 8 wk experiments relating concentration to the concentration in soil the soil organic matter content, and the degree of chlorination. 20 refs., 3 figs., 1 tab.

  17. Indication of metal homeostasis disturbance in earthworm Eisenia fetida after exposure to semi-solid depot sludge.

    PubMed

    Babi?, Sanja; Dragun, Zrinka; Sauerborn Klobu?ar, Roberta; Ivankovi?, Dušica; Ba?i?, Niko; Fiket, Željka; Bariši?, Josip; Krasni?i, Nesrete; Strunjak-Perovi?, Ivan?ica; Topi? Popovi?, Natalija; ?ož-Rakovac, Rozelindra

    2015-09-01

    Treated sewage sludge is commonly used in agriculture as fertilizer. It is, therefore, necessary to determine possible detrimental influences of sludge application on soil contamination and accumulation of contaminants in tissues of terrestrial animals, which in the long run could also have undesirable effects on humans. With that aim, the study was performed using earthworm Eisenia fetida as test organism and semi-solid depot sludge from a wastewater treatment plant as exposure media. The concentrations of 26 metals/metalloids were determined in depot sludge, and their bioaccumulation was estimated in whole tissue of E. fetida, and for the first time in the soluble tissue fraction, which represents metal fraction available for metabolic requirements and toxic effects. Obtained results have revealed acceptable levels of several elements (Cd, Cr, Cu, Ni, Pb, Zn) in depot sludge, when compared to currently valid regulations, and only moderate accumulation of some elements (e.g. As, Ba, Cd, Co, Fe, Tl, V, and Zn) in earthworms, as a consequence of exposure to depot sludge. However, a concentration increase after exposure to depot sludge was observed in E. fetida for several elements (Cd, Mo, and Zn), which were present in lower concentrations in the exposure mixtures than in soil. Contrary, a concentration decrease was observed for Cs, Mn, and Rb, although they were present in higher concentrations in depot sludge than in soil. It was an indication of disturbance in metal homeostasis in earthworms, possibly caused by exposure to complex mixture of contaminants present in depot sludge. The cumulative effect of exposure to a number of various contaminants (inorganic, organic, microbiological and pharmaceutical), even if each of them was not present in very high concentrations, could have caused distress in earthworms exposed to depot sludge. PMID:25931022

  18. Aircraft wake turbulence avoidance

    NASA Technical Reports Server (NTRS)

    Mcgowan, W. A.

    1971-01-01

    Analytical studies and flight tests are used to describe the formation and severity of trailing vortices and the spatial extent of their influence. This information is then used to outline procedures for ready application by pilots, tower operators, and others concerned with the flow of traffic. The procedures provide the necessary appreciation of the physical attributes of trailing vortices, the potential hazards involved when encountering them, and how best to avoid the dangerous portions of the wake during flight operations.

  19. Soil Penetration by Earthworms and Plant Roots—Mechanical Energetics of Bioturbation of Compacted Soils

    PubMed Central

    2015-01-01

    We quantify mechanical processes common to soil penetration by earthworms and growing plant roots, including the energetic requirements for soil plastic displacement. The basic mechanical model considers cavity expansion into a plastic wet soil involving wedging by root tips or earthworms via cone-like penetration followed by cavity expansion due to pressurized earthworm hydroskeleton or root radial growth. The mechanical stresses and resulting soil strains determine the mechanical energy required for bioturbation under different soil hydro-mechanical conditions for a realistic range of root/earthworm geometries. Modeling results suggest that higher soil water content and reduced clay content reduce the strain energy required for soil penetration. The critical earthworm or root pressure increases with increased diameter of root or earthworm, however, results are insensitive to the cone apex (shape of the tip). The invested mechanical energy per unit length increase with increasing earthworm and plant root diameters, whereas mechanical energy per unit of displaced soil volume decreases with larger diameters. The study provides a quantitative framework for estimating energy requirements for soil penetration work done by earthworms and plant roots, and delineates intrinsic and external mechanical limits for bioturbation processes. Estimated energy requirements for earthworm biopore networks are linked to consumption of soil organic matter and suggest that earthworm populations are likely to consume a significant fraction of ecosystem net primary production to sustain their subterranean activities. PMID:26087130

  20. Heavy metal concentrations in earthworms from soil amended with sewage sludge

    USGS Publications Warehouse

    Beyer, W.N.; Chaney, R.L.; Mulhern, B.M.

    1982-01-01

    Metal concentrations in soil may be elevated considerably when metal-laden sewage sludge is spread on land. Metals in earthworms (Lumbricidae) from agricultural fields amended with sewage sludge and from experimental plots were examined to determine if earthworms are important in transferring metals in soil to wildlife. Earthworms from four sites amended with sludge contained significantly (P . < 0.05) more Cd (12 times), Cu (2.4 times), Zn (2.0 times), and Pb (1.2 times) than did earthworms from control sites, but the concentrations detected varied greatly and depended on the particular sludge application. Generally, Cd and Zn were concentrated by earthworms relative to soil, and Cu, Pb, and Ni were not concentrated. Concentrations of Cd, Zn, Cu, and Pb in earthworms were correlated (P < 0.05) with those in soil. The ratio of the concentration of metals in earthworms to the concentration of metals in soil tended to be lower in contaminated soil than in clean soil. Concentrations of Cd as high as 100 ppm (dry wt) were detected in earthworms from soil containing only 2 ppm Cd. These concentrations are considered hazardous to wildlife that eat worms. Liming soil decreased Cd concentrations in earthworms slightly (P < 0.05) but had no discernible effect on concentrations of the other metals studied. High Zn concentrations in soil substantially reduced Cd concentrations in earthworms.

  1. The earthworm Aporrectodea caliginosa stimulates abundance and activity of phenoxyalkanoic acid herbicide degraders

    PubMed Central

    Liu, Ya-Jun; Zaprasis, Adrienne; Liu, Shuang-Jiang; Drake, Harold L; Horn, Marcus A

    2011-01-01

    2-Methyl-4-chlorophenoxyacetic acid (MCPA) is a widely used phenoxyalkanoic acid (PAA) herbicide. Earthworms represent the dominant macrofauna and enhance microbial activities in many soils. Thus, the effect of the model earthworm Aporrectodea caliginosa (Oligochaeta, Lumbricidae) on microbial MCPA degradation was assessed in soil columns with agricultural soil. MCPA degradation was quicker in soil with earthworms than without earthworms. Quantitative PCR was inhibition-corrected per nucleic acid extract and indicated that copy numbers of tfdA-like and cadA genes (both encoding oxygenases initiating aerobic PAA degradation) in soil with earthworms were up to three and four times higher than without earthworms, respectively. tfdA-like and 16S rRNA gene transcript copy numbers in soil with earthworms were two and six times higher than without earthworms, respectively. Most probable numbers (MPNs) of MCPA degraders approximated 4 × 105?gdw?1 in soil before incubation and in soil treated without earthworms, whereas MPNs of earthworm-treated soils were approximately 150 × higher. The aerobic capacity of soil to degrade MCPA was higher in earthworm-treated soils than in earthworm-untreated soils. Burrow walls and 0–5?cm depth bulk soil displayed higher capacities to degrade MCPA than did soil from 5–10?cm depth bulk soil, expression of tfdA-like genes in burrow walls was five times higher than in bulk soil and MCPA degraders were abundant in burrow walls (MPNs of 5 × 107?gdw?1). The collective data indicate that earthworms stimulate abundance and activity of MCPA degraders endogenous to soil by their burrowing activities and might thus be advantageous for enhancing PAA degradation in soil. PMID:20740027

  2. Zaprinast and Rolipram Enhances Spatial and Emotional Memory in the Elevated Plus Maze and Passive Avoidance Tests and Diminishes Exploratory Activity in Naive Mice

    PubMed Central

    Akar, Furuzan; Mutlu, Oguz; Celikyurt, Ipek Komsuoglu; Ulak, Guner; Erden, Faruk; Bektas, Emine; Tanyeri, Pelin

    2014-01-01

    Background Phosphodiesterase (PDE) inhibitors in the central nervous system have been shown to stimulate neuronal functions and increase neurogenesis in Alzheimer disease (AD) patients. Material/Methods The aim of this study was to investigate the effects of zaprinast, a PDE5 inhibitor, and rolipram, a PDE4 inhibitor, on learning and memory in elevated plus maze (EPM) and passive avoidance (PA) tests in naive mice. Male Balb-c mice received short-term treatment with zaprinast (3 and 10 mg/kg) and rolipram (0.05 and 0.1 mg/kg) before the acquisition trial of the EPM and PA tests. The exploratory activity of the animals was also investigated in the Hughes box test. Results Both zaprinast (10 mg/kg) and rolipram (0.1 mg/kg) significantly decreased second-day latency compared to the control group in the EPM test, while only rolipram (0.1 mg/kg) significantly increased second-day latency in the PA test. Both zaprinast (10 mg/kg) and rolipram (0.1 mg/kg) significantly decreased the number of entries to new areas and time spent in new areas in the Hughes box test. Conclusions Our study revealed that both zaprinast and rolipram enhanced spatial memory in EPM, while rolipram seemed to have more emotional memory-enhancing effects in the PA test compared to zaprinast. Both zaprinast and rolipram diminished exploratory activity in the Hughes box test, which can be attributed to the drugs’ anxiogenic effects. PMID:25057848

  3. Fostering assumption-based stress-test thinking in managing groundwater systems: learning to avoid failures due to basic dynamics

    NASA Astrophysics Data System (ADS)

    Guillaume, Joseph H. A.; El Sawah, Sondoss

    2014-06-01

    Sustainable groundwater resource management can only be achieved if planning processes address the basic dynamics of the groundwater system. Conceptual and distributed groundwater models do not necessarily translate into an understanding of how a plan might operate in reality. Prompted by Australian experiences, `iterative closed-question modelling' has been used to develop a process of iterative dialogue about management options, objectives and knowledge. Simple hypothetical models of basic system dynamics that satisfy agreed assumptions are used to stress-test the ability of a proposed management plan to achieve desired future conditions. Participants learn from models in which a plan succeeds and fails, updating their assumptions, expectations or plan. Their new understanding is tested against further hypothetical models. The models act as intellectual devices that confront users with new scenarios to discuss. This theoretical approach is illustrated using simple one and two-cell groundwater models that convey basic notions of capture and spatial impacts of pumping. Simple extensions can address uncertain climate, managed-aquifer recharge and alternate water sources. Having learnt to address the dynamics captured by these models, participants may be better placed to address local conditions and develop more effective arrangements to achieve management outcomes.

  4. Abundance of earthworm species in Estonian arable soils

    Microsoft Academic Search

    Mari Ivask; Annely Kuu; Eduard Sizov

    2007-01-01

    Specific composition of earthworm community has indicative value for evaluating the impact of agricultural practice on soil. The occurrence of species only like Aporrectodea caliginosa, Aporrectodea rosea, Lumbricus rubellus tolerant to disturbance is the result of intensive tillage and agricultural practice or the influence of strong limiting ecological factor. A community including more sensitive species Lumbricus terrestris and Aporrectodea longa,

  5. Partitioning of habitable pore space in earthworm burrows

    PubMed Central

    Amador, Jose A.

    2010-01-01

    Earthworms affect macro-pore structure of soils. However, some studies suggest that earthworm burrow walls and casts themselves differ greatly in structure from surrounding soils, potentially creating habitat for microbivorours nematodes which accelerate the decomposition and C and N mineralization. In this study aggregates were sampled from the burrow walls of the anecic earthworm Lumbricus terrestris and bulk soil (not altered by earthworms) from mesocosm incubated in the lab for 0, 1, 3, 5 and 16 weeks. Pore volumes and pore sizes were measured in triplicate with Mercury Intrusion Porosimetry (MIP). This method is well suited to establish pore size structure in the context of habitat, because it measures the stepwise intrusion of mercury from the outside of the aggregate into ever smaller pores. The progress of mercury into the aggregate interior thus resembles potential paths of a nematode into accessible habitable pore spaces residing in an aggregate. Total specific pore volume, Vs, varied between 0.13 and 0.18 mL/g and increased from 3 to 16 weeks in both burrow and bulk soil. Differences between total Vs of bulk and burrow samples were not significant on any sampling date. However, differences were significant for pore size fractions at the scale of nematode body diameter. PMID:22736839

  6. EARTHWORMS OF THE WESTERN UNITED STATES. PART 1. LUMBRICIDAE

    EPA Science Inventory

    The earthworm fauna of the western United States is an amalgam of native and introduced elements. While the native species are mostly members of the family Megascolecidae, and closely related to those of Australia and Southeast Asia, the introduced species are, at least in the No...

  7. The influence of collembolans and earthworms on AM fungal mycelium

    Microsoft Academic Search

    Dagmar Gormsen; Pĺl Axel Olsson; Katarina Hedlund

    2004-01-01

    Arbuscular mycorrhizal (AM) mycelia are dependent on contact with plant roots for spore formation. In this study, earthworms and collembolans were regarded as potential dispersal vectors of AM fungal spores and hyphae, and we determined how they influenced the extension of AM fungi from host plant roots. Plantago lanceolata seedlings were grown in a mesh bag with an AM inoculum

  8. Impact of biochar on earthworm populations: A review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the overwhelming importance of earthworm activity in the soil system, there are a limited number of studies that have examined the impact resulting from biochar addition to soil. Biochar is part of the black carbon continuum of chemo-thermal converted biomass. This review summarizes existing...

  9. Assessing the ecotoxicological effects of long-term contaminated mine soils on plants and earthworms: relevance of soil (total and available) and body concentrations.

    PubMed

    García-Gómez, Concepción; Esteban, Elvira; Sánchez-Pardo, Beatriz; Fernández, María Dolores

    2014-09-01

    The interactions and relevance of the soil (total and available) concentrations, accumulation, and acute toxicity of several essential and non-essential trace elements were investigated to determine their importance in environmental soil assessment. Three plant species (T. aestivum, R. sativum, and V. sativa) and E. fetida were simultaneously exposed for 21 days to long-term contaminated soils collected from the surroundings of an abandoned pyrite mine. The soils presented different levels of As and metals, mainly Zn and Cu, and were tested at different soil concentrations [12.5, 25, 50, and 100% of contaminated soil/soil (w/w)] to increase the range of total and available soil concentrations necessary for the study. The total concentrations in the soils (of both As and metals) were better predictors of earthworm uptake than were the available concentrations. In plants, the accumulation of metals was related to the available concentrations of Zn and Cu, which could indicate that plants and earthworms accumulate elements from different pools of soil contaminants. Moreover, Zn and Cu, which are essential elements, showed controlled uptake at low concentrations. The external metal concentrations predicted earthworm mortality, whereas in plants, the effects on growth were correlated to the As and metal contents in the plants. In general, the bioaccumulation factors were lower at higher exposure levels, which implies the existence of auto-regulation in the uptake of both essential and non-essential elements by plants and earthworms. PMID:24875255

  10. Aqueous and lipid nuclear magnetic resonance metabolomic profiles of the earthworm Aporrectodea caliginosa show potential as an indicator species for environmental metabolomics.

    PubMed

    Brown, Jeffrey N; Samuelsson, Linda; Bernardi, Giuliana; Gooneratne, Ravi; Larsson, D G Joakim

    2014-10-01

    The common pasture earthworm Aporrectodea caliginosa has often been neglected in environmental metabolomics in favor of species easily bred in the laboratory. The present study assigns aqueous metabolites in A. caliginosa using high-resolution 1- and 2-dimensional nuclear magnetic resonance (NMR) spectroscopy. In total, 51 aqueous metabolites were identified, including typical amino acids (alanine, leucine, asparagine, phenylalanine), sugars (maltose, glucose), the dominant earthworm-specific 2-hexyl-5-ethyl-furansulfonate, and several previously unreported metabolites (oxoglutarate, putrescine). Examining the lesser-known earthworm lipid metabolome showed various lipid fatty acyl chains, cholesterol, and phosphatidylcholine. To briefly test if the NMR metabolomic techniques could differentiate A. caliginosa from different sites, earthworms were collected from 2 adjacent farms. Orthogonal partial least squares discriminant analysis detected metabolomic differences, suggesting the worms from the 2 sites differed in their energy metabolism, as indicated by altered levels of alanine, glutamine, glutamate, malate, fumarate, and lipids. Evidence of greater utilization of lipid energy reserves and onset of protein catabolism was also present. While the precise cause of the metabolomic differences could not be determined, the results show the potential of this species for further environmental metabolomic studies. PMID:24995628

  11. Ternary toxicological interactions of insecticides, herbicides, and a heavy metal on the earthworm Eisenia fetida.

    PubMed

    Wang, Yanhua; Chen, Chen; Qian, Yongzhong; Zhao, Xueping; Wang, Qiang

    2015-03-01

    The combined toxicities of five insecticides (chlorpyrifos, avermectin, imidacloprid, ?-cyhalothrin, and phoxim), two herbicides (atrazine and butachlor), and a heavy metal (cadmium) have been examined using the acute toxicity test on the earthworm. With a concentration of 2.75 mg/kg being lethal for 50% of the organisms, imidacloprid exhibited the highest acute toxicity toward the earthworm Eisenia fetida. Toxicological interactions of these chemicals in ternary mixtures were studied using the combination-index (CI) equation method. Twenty-one ternary mixtures exhibited various interactive effects, in which 11 combinations showed synergistic effects, four led to dual synergistic/additive behaviors, one exhibited an additive effect, and five showed increasing antagonism within the entire range of effects. The CI method was compared with the classical models of concentration addition and independent action, and it was found that the CI method could accurately predict combined toxicity of the chemicals studied. The predicted synergism in the majority of the mixtures, especially at low-effect levels, might have implications in the real terrestrial environment. PMID:25463238

  12. Earthworm populations and species distributions under no-till and conventional tillage in Indiana and Illinois

    Microsoft Academic Search

    Eileen J. Kladivko; Neela M. Akhouri; Glenn Weesies

    1997-01-01

    Earthworms often play an important role in maintaining or improving soil physical conditions, and earthworm populations often increase under reduced tillage systems. The objective of our study was to determine earthworm populations and species distributions under long-term no-till vs conventional tillage on a variety of soil types in the states of Indiana and Illinois, U.S.A. Fourteen paired sites were located

  13. Growth and fecundity of earthworms: Perionyx excavatus and Perionyx sansibaricus in cattle waste solids

    Microsoft Academic Search

    Surindra Suthar

    2009-01-01

    Epigeic earthworms (Oligochaeta) have been appeared as key organisms to convert organic waste resources into value-added products,\\u000a i.e., vermicompost and worm biomass. The assessment of reproduction potential of composting earthworm may be beneficial for\\u000a large-scale earthworm production. Although, the waste minimizing potential of Perionyx excavatus and Perionyx sansibaricus is well proved, but little information is available about their fecundity rate.

  14. Earthworm and belowground competition effects on plant productivity in a plant diversity gradient.

    PubMed

    Eisenhauer, Nico; Milcu, Alexandru; Nitschke, Norma; Sabais, Alexander C W; Scherber, Christoph; Scheu, Stefan

    2009-08-01

    Diversity is one major factor driving plant productivity in temperate grasslands. Although decomposers like earthworms are known to affect plant productivity, interacting effects of plant diversity and earthworms on plant productivity have been neglected in field studies. We investigated in the field the effects of earthworms on plant productivity, their interaction with plant species and functional group richness, and their effects on belowground plant competition. In the framework of the Jena Experiment we determined plant community productivity (in 2004 and 2007) and performance of two phytometer plant species [Centaurea jacea (herb) and Lolium perenne (grass); in 2007 and 2008] in a plant species (from one to 16) and functional group richness gradient (from one to four). We sampled earthworm subplots and subplots with decreased earthworm density and reduced aboveground competition of phytometer plants by removing the shoot biomass of the resident plant community. Earthworms increased total plant community productivity (+11%), legume shoot biomass (+35%) and shoot biomass of the phytometer C. jacea (+21%). Further, phytometer performance decreased, i.e. belowground competition increased, with increasing plant species and functional group richness. Although single plant functional groups benefited from higher earthworm numbers, the effects did not vary with plant species and functional group richness. The present study indicates that earthworms indeed affect the productivity of semi-natural grasslands irrespective of the diversity of the plant community. Belowground competition increased with increasing plant species diversity. However, belowground competition was modified by earthworms as reflected by increased productivity of the phytometer C. jacea. Moreover, particularly legumes benefited from earthworm presence. Considering also previous studies, we suggest that earthworms and legumes form a loose mutualistic relationship affecting essential ecosystem functions in temperate grasslands, in particular decomposition and plant productivity. Further, earthworms likely alter competitive interactions among plants and the structure of plant communities by beneficially affecting certain plant functional groups. PMID:19526252

  15. Gene expression analysis of CL-20-induced reversible neurotoxicity reveals GABA(A) receptors as potential targets in the earthworm Eisenia fetida.

    PubMed

    Gong, Ping; Guan, Xin; Pirooznia, Mehdi; Liang, Chun; Perkins, Edward J

    2012-01-17

    The earthworm Eisenia fetida is one of the most used species in standardized soil ecotoxicity tests. End points such as survival, growth, and reproduction are eco-toxicologically relevant but provide little mechanistic insight into toxicity pathways, especially at the molecular level. Here we apply a toxicogenomic approach to investigate the mode of action underlying the reversible neurotoxicity of hexanitrohexaazaisowurtzitane (CL-20), a cyclic nitroamine explosives compound. We developed an E. fetida-specific shotgun microarray targeting 15119 unique E. fetida transcripts. Using this array we profiled gene expression in E. fetida in response to exposure to CL-20. Eighteen earthworms were exposed for 6 days to 0.2 ?g/cm(2) of CL-20 on filter paper, half of which were allowed to recover in a clean environment for 7 days. Nine vehicle control earthworms were sacrificed at days 6 and 13, separately. Electrophysiological measurements indicated that the conduction velocity of earthworm medial giant nerve fiber decreased significantly after 6-day exposure to CL-20, but was restored after 7 days of recovery. Total RNA was isolated from the four treatment groups including 6-day control, 6-day exposed, 13-day control, and 13-day exposed (i.e., 6-day exposure followed by 7-day recovery), and was hybridized to the 15K shotgun oligo array. Statistical and bioinformatic analyses suggest that CL-20 initiated neurotoxicity by noncompetitively blocking the ligand-gated GABA(A) receptor ion channel, leading to altered expression of genes involved in GABAergic, cholinergic, and Agrin-MuSK pathways. In the recovery phase, expression of affected genes returned to normality, possibly as a result of autophagy and CL-20 dissociation/metabolism. This study provides significant insights into potential mechanisms of CL-20-induced neurotoxicity and the recovery of earthworms from transient neurotoxicity stress. PMID:22191394

  16. Localization and characterization of sulfated glycosaminoglycans in the body of the earthworm Eisenia andrei (Oligochaeta, Annelida).

    PubMed

    Amaral, Hanna B F; Mateus, Samuel H; Ferreira, Laina C; Ribeiro, Cristiane C; Palumbo-Junior, Antonio; Domingos, Maria-Aparecida O; Cinelli, Leonardo P; Costa-Filho, Adilson; Nasciutti, Luiz E; Silva, Luiz-Claudio F

    2011-07-01

    The aim of this study was to characterize the compartmental distribution of sulfated glycosaminoglycans (S-GAGs) in adults and their occurrence during the development of the earthworm Eisenia andrei. S-GAGs were extracted from the body of earthworms to identify their composition and the time of their appearance and disappearance in embryonic, newborn, juvenile, and adult earthworms. S-GAGs were also analyzed in earthworm tissue using histochemical metachromatic staining. Purified S-GAGs obtained from the whole body of adult earthworms were composed of chondroitin sulfate (CS) and heparan sulfate (HS). In addition, an unknown, highly sulfated polysaccharide (HSP) was detected. In order to characterize specifically the S-GAG composition in the integument, earthworms were dissected and as much as possible of their viscera was removed. HS and CS were the predominant sulfated polysaccharides in the dissected integument, whereas in viscera, CS, HS and the HSP were found in proportions similar to those identified in the body. The qualitative S-GAG composition in juveniles was similar to that obtained from adult earthworms. CS was the predominant S-GAG in newborn earthworms, accompanied by lesser amounts of HS and by tiny amounts of the HSP. This study provides a detailed descriptive account of the pattern of S-GAG synthesis during development, and also the characterization of the tissue distribution of these compounds in the body of earthworms. PMID:20546857

  17. Received 28 Apr 2013 | Accepted 9 Sep 2013 | Published 15 Oct 2013 Earthworms facilitate carbon sequestration through

    E-print Network

    Neher, Deborah A.

    carbon sequestration through unequal amplification of carbon stabilization compared with mineralization carbon would entirely reflect the earthworms' contribution to net carbon sequestration. We show how two widespread earthworm invaders affect net carbon sequestration through impacts on the balance of carbon

  18. How to reduce false positive results when undertaking in vitro genotoxicity testing and thus avoid unnecessary follow-up animal tests: Report of an ECVAM Workshop

    Microsoft Academic Search

    David Kirkland; Stefan Pfuhler; David Tweats; Marilyn Aardema; Raffaella Corvi; Firouz Darroudi; Azeddine Elhajouji; Hansruedi Glatt; Paul Hastwell; Makoto Hayashi; Peter Kasper; Stephan Kirchner; Anthony Lynch; Daniel Marzin; Daniela Maurici; Jean-Roc Meunier; Lutz Müller; Gerhard Nohynek; James Parry; Elizabeth Parry; Veronique Thybaud; Ray Tice; Jan van Benthem; Philippe Vanparys; Paul White

    2007-01-01

    Workshop participants agreed that genotoxicity tests in mammalian cells in vitro produce a remarkably high and unacceptable occurrence of irrelevant positive results (e.g. when compared with rodent carcinogenicity). As reported in several recent reviews, the rate of irrelevant positives (i.e. low specificity) for some studies using in vitro methods (when compared to this “gold standard”) means that an increased number

  19. Earthworm-Mycorrhiza Interactions Can Affect the Diversity, Structure and Functioning of Establishing Model Grassland Communities

    PubMed Central

    Zaller, Johann G.; Heigl, Florian; Grabmaier, Andrea; Lichtenegger, Claudia; Piller, Katja; Allabashi, Roza; Frank, Thomas; Drapela, Thomas

    2011-01-01

    Both earthworms and arbuscular mycorrhizal fungi (AMF) are important ecosystem engineers co-occurring in temperate grasslands. However, their combined impacts during grassland establishment are poorly understood and have never been studied. We used large mesocosms to study the effects of different functional groups of earthworms (i.e., vertically burrowing anecics vs. horizontally burrowing endogeics) and a mix of four AMF taxa on the establishment, diversity and productivity of plant communities after a simulated seed rain of 18 grassland species comprising grasses, non-leguminous forbs and legumes. Moreover, effects of earthworms and/or AMF on water infiltration and leaching of ammonium, nitrate and phosphate were determined after a simulated extreme rainfall event (40 l m?2). AMF colonisation of all three plant functional groups was altered by earthworms. Seedling emergence and diversity was reduced by anecic earthworms, however only when AMF were present. Plant density was decreased in AMF-free mesocosms when both anecic and endogeic earthworms were active; with AMF also anecics reduced plant density. Plant shoot and root biomass was only affected by earthworms in AMF-free mesocosms: shoot biomass increased due to the activity of either anecics or endogeics; root biomass increased only when anecics were active. Water infiltration increased when earthworms were present in the mesocosms but remained unaffected by AMF. Ammonium leaching was increased only when anecics or a mixed earthworm community was active but was unaffected by AMF; nitrate and phosphate leaching was neither affected by earthworms nor AMF. Ammonium leaching decreased with increasing plant density, nitrate leaching decreased with increasing plant diversity and density. In order to understand the underlying processes of these interactions further investigations possibly under field conditions using more diverse belowground communities are required. Nevertheless, this study demonstrates that belowground-aboveground linkages involving earthworms and AMF are important mediators of the diversity, structure and functioning of plant communities. PMID:22216236

  20. Invasive and exotic earthworms: an unaccounted change to mercury cycling in northeastern US forest soils

    NASA Astrophysics Data System (ADS)

    Richardson, J. B.; Friedland, A. J.; Görres, J. H.; Renock, D. J.; Jackson, B. P.

    2014-12-01

    Invasive and exotic earthworms are now present in many forested areas of the northeastern US with currently unquantified consequences to abiotic and biotic Hg cycling. To quantify these effects, we measured Hg concentrations (mg kg-1) and amounts (?g m-2) in earthworms and soil horizons at 45 soil pits from 9 sites in northern New England. Seven earthworm species were observed in varying assemblages. Most earthworm species attained concentrations of Hg potentially hazardous to wildlife that may ingest them, with highest concentrations found in shallow-burrowing, litter-feeders. Specifically, Aporrectodea rosea and Amynthas agrestis had the greatest Hg concentrations (0.9 ± 0.1) and Hg amounts (8 ± 2) ?g m-2. Aporrectodea rosea and Amynthas agrestis were found to inhabit the forest floor and the top 5 cm of the mineral horizons in high abundance, potentially making it a readily accessible prey species. Bioaccumulation of Hg by invasive and exotic earthworms may be an important mechanism that transfers Hg to ground foraging predators, such as thrushes, red-backed salamanders and foxes, which is generally unaccounted for in terrestrial food chains. Earthworm Hg concentrations were poorly correlated with their respective soil Hg concentrations, suggesting a species dependence for Hg bioaccumulation rather than site effects. We observed that forest floor Hg concentrations and amounts were 23% and 57% lower, respectively, at soil pits with earthworms compared to those without. Moreover, Hg amounts in forest floor-feeding earthworms exceeded the remaining forest floor Hg pools. Mercury concentrations and pools in the mineral soil were 21% and 33% lower, respectively, for soil pits with earthworms compared to those without. We hypothesize that enhanced decomposition, horizon disturbance and bioaccumulation by earthworms has decreased Hg amounts in the forest floor and mineral soil. Our results suggest that earthworms are decreasing Hg storage in forest soils with potential hazardous impacts for predatory animals in northeastern US forests and other ecosystems.

  1. Novel microsatellite loci for the compost earthworm Eisenia fetida: A genetic comparison of three North American vermiculture stocks

    Microsoft Academic Search

    Christopher M. Somers; Kara Neudorf; Kenneth L. Jones; Stacey L. Lance

    2011-01-01

    Earthworms are important components of soil ecosystems worldwide, and have been used extensively as indicator species in ecotoxicology studies. Our understanding of mating systems, population structure, and genetic diversity in earthworms is limited by the current lack of available genetic tools. To address this gap, we developed 16 novel microsatellite markers for the compost earthworm Eisenia fetida, one of the

  2. Activities of the digestive enzymes in the gut and in tissue culture of a tropical geophagous earthworm, Polypheretima elongata (Megascolecidae)

    Microsoft Academic Search

    C. Lattaud; B. G. Zhang; S. Locati; C. Rouland; P. Lavelle

    1997-01-01

    Endogeic geophagous earthworms from tropical areas seem to digest soil organic matter through a mutualist earthworm microflora-digestion system and the intestinal mucus produced by earthworms was supposed to play a central role in the process of digestion. A large range of glucosidic substrates characteristic of plant material was used to reveal the activities of digestive enzymes in the gut (wall

  3. Earthworms and the Degradation of Lactic Acid–Based Stereocopolymers

    Microsoft Academic Search

    N. Alauzet; H. Garreau; M. Bouché; M. Vert

    2002-01-01

    Two lactic acid–based stereocopolymers, namely 50\\/50 and 96\\/4 L\\/D poly(l-lactic-co-d-lactic acids) and corresponding oligomers, were allowed to age under different conditions in order to investigate their toxicity and that of some potential degradation by-products, namely lactic acid and sodium and calcium lactates, to earthworms. Degradation characteristics in various worm-free and worm-containing media were also investigated under various conditions including direct

  4. Feeding activity of the earthworm Eisenia andrei in artificial soil

    Microsoft Academic Search

    Tjalling Jager; Roel H. L. J. Fleuren; Willem Roelofs; Arthur C. de Groot

    2003-01-01

    Quantitative information on the feeding activity of earthworms is scarce but this information is valuable in many eco(toxico)logical studies. In this study, the feeding activity of the compost worm Eisenia andrei is examined in artificial soil (OECD medium), with and without a high-quality food source (cow manure), and at two temperatures (10 and 20°C). Methods are provided to estimate the

  5. Production of Feed Protein From Animal Waste by Earthworms

    Microsoft Academic Search

    C. A. Edwards

    1985-01-01

    The 84 Mt of cattle waste, 9 Mt of pig waste and 4-5 Mt of poultry waste produced annually in the U.K. create serious disposal problems. Research at Rothamsted since 1980 has shown that the earthworm Eisenia foetida and other species can break down these wastes rapidly under controlled conditions to provide valuable horticultural composts and high-grade protein suitable for

  6. Transmission of Nephridial Bacteria of the Earthworm Eisenia fetida

    PubMed Central

    Davidson, Seana K.; Stahl, David A.

    2006-01-01

    The lumbricid earthworms (annelid family Lumbricidae) harbor gram-negative bacteria in their excretory organs, the nephridia. Comparative 16S rRNA gene sequencing of bacteria associated with the nephridia of several earthworm species has shown that each species of worm harbors a distinct bacterial species and that the bacteria from different species form a monophyletic cluster within the genus Acidovorax, suggesting that there is a specific association resulting from radiation from a common bacterial ancestor. Previous microscopy and culture studies revealed the presence of bacteria within the egg capsules and on the surface of embryos but did not demonstrate that the bacteria within the egg capsule were the same bacteria that colonized the nephridia. We present evidence, based on curing experiments, in situ hybridizations with Acidovorax-specific probes, and 16S rRNA gene sequence analysis, that the egg capsules contain high numbers of the bacterial symbiont and that juveniles are colonized during development within the egg capsule. Studies exposing aposymbiotic hatchlings to colonized adults and their bedding material suggested that juvenile earthworms do not readily acquire bacteria from the soil after hatching but must be colonized during development by bacteria deposited in the egg capsule. Whether this is due to the developmental stage of the host or the physiological state of the symbiont remains to be investigated. PMID:16391117

  7. Transmission of nephridial bacteria of the earthworm Eisenia fetida.

    PubMed

    Davidson, Seana K; Stahl, David A

    2006-01-01

    The lumbricid earthworms (annelid family Lumbricidae) harbor gram-negative bacteria in their excretory organs, the nephridia. Comparative 16S rRNA gene sequencing of bacteria associated with the nephridia of several earthworm species has shown that each species of worm harbors a distinct bacterial species and that the bacteria from different species form a monophyletic cluster within the genus Acidovorax, suggesting that there is a specific association resulting from radiation from a common bacterial ancestor. Previous microscopy and culture studies revealed the presence of bacteria within the egg capsules and on the surface of embryos but did not demonstrate that the bacteria within the egg capsule were the same bacteria that colonized the nephridia. We present evidence, based on curing experiments, in situ hybridizations with Acidovorax-specific probes, and 16S rRNA gene sequence analysis, that the egg capsules contain high numbers of the bacterial symbiont and that juveniles are colonized during development within the egg capsule. Studies exposing aposymbiotic hatchlings to colonized adults and their bedding material suggested that juvenile earthworms do not readily acquire bacteria from the soil after hatching but must be colonized during development by bacteria deposited in the egg capsule. Whether this is due to the developmental stage of the host or the physiological state of the symbiont remains to be investigated. PMID:16391117

  8. Collision avoidance at sea

    Microsoft Academic Search

    Thomas L. Vincent

    The problem of collision avoidance between surface ships may be examined from the perspective of either macro or micro collision avoidance. In macro collision avoidance the pilot of a ship would try for maintaining a given mileage separation between his own ship and others. Micro collision avoidance would be concerned with manoeuvres between ships of less than a given separation

  9. Relative abundance and seasonal activity of earthworms (Lumbricidae and Megascolecidae) as determined by hand-sorting and formalin extraction in forest soils on the southern Appalachian Piedmont

    Microsoft Academic Search

    M. A. Callaham; P. F. Hendrix

    1997-01-01

    The relative efficiency of different sampling methods for earthworms may vary with site characteristics, season and earthworm species. We conducted a study in which earthworms were collected by hand-sorting and by formalin extraction in a successional, mixed hardwood-pine forest. The efficiency of each collecting technique was assessed in terms of seasonal trends, soil physical properties and species collected. Earthworm community

  10. An exploration of the relationship between adsorption and bioavailability of pesticides in soil to earthworm.

    PubMed

    Yu, Yun Long; Wu, Xiao Mao; Li, Shao Nan; Fang, Hua; Zhan, Hai Yan; Yu, Jing Quan

    2006-06-01

    A study was conducted to determine the adsorption/desorption of butachlor, myclobutanil and chlorpyrifos on five soils using a batch equilibration technique and to study the relationship between bioavailability to Allolobophora caliginosa and the adsorption/desorption of these three pesticides. The results showed that the adsorption/desorption processes of the tested compounds were mainly controlled by soil organic matter content (OM) and octanol/water-partitioning coefficient (K(ow)), and that the bioavailability of the pesticides was dependent on characteristics of pesticides, properties of soils, and uptake routes of earthworms. Bioconcentration of butachlor and myclobutanil was negatively correlated with Freundlich adsorption constant K(af) and K(df). However, only a slightly positive correlation between bioconcentration and K(af) and K(df) was observed for chlorpyrifos due to its high affinity onto soil. PMID:16274907

  11. Effect of the Heavy Metals Cu, Ni, Cd and Zn on the Growth and Reproduction of Epigeic Earthworms ( E. fetida ) during the Vermistabilization of Municipal Sewage Sludge

    Microsoft Academic Search

    Miguel A. Domínguez-Crespo; Z. Erika Sánchez-Hernández; Aidé M. Torres-Huerta; Ma. de la Luz X. Negrete-Rodríguez; Eloy Conde-Barajas; Abelardo Flores-Vela

    In order to enhance the removal of heavy metals such as Ni, Cu, Zn and Cd from wastewater, different cow dung\\/sewage sludge\\u000a ratios were tested to assess the effect of these metals on the adaptability of Eisenia fetida earthworms to the treatment process carried out in a typical plant located in Tamaulipas, Mexico. Two experimental water\\u000a treatment setups were proposed.

  12. The effects of the insecticide lambda-Cyhalothrin on the earthworm Eisenia fetida under experimental conditions of tropical and temperate regions

    Microsoft Academic Search

    Marcos Garcia; Adam Scheffczyk; Terezinha Garcia; Jörg Römbke

    2011-01-01

    Plant Protection Products can affect soil organisms and thus might have negative impacts on soil functions. Little research has been performed on their impact on tropical soils. Therefore, the effects of the insecticide lambda-Cyhalothrin on earthworms were evaluated in acute and chronic laboratory tests modified for tropical conditions, i.e. at selected temperatures (20 and 28°C) and with two strains (temperate

  13. Effect of earthworm casts on protein synthesis in radish ( Raphanus sativum ) and lettuce ( Lactuga sativa ) seedlings

    Microsoft Academic Search

    U. Tomati; E. Galli; A. Grappelli; G. Di Lena

    1990-01-01

    The protein-synthesizing capacity of 3-day-old seedlings of radish and lettuce grown in the presence of earthworm casts was investigated using L-14-C-leucine incorporation. The results showed that earthworm casts increased protein synthesis by 24% for lettuce and 32% for radish, althought no significant differences in protein content were evident.

  14. Modeling ingestion as an exposure route for organic chemicals in earthworms (Oligochaeta)

    Microsoft Academic Search

    T. Jager

    2004-01-01

    Earthworms take up chemicals from both soil pore water and food, but the quantitative contribution of each route is unclear. In this paper, a model is presented for the accumulation of organic chemicals in earthworms, including a compartment for the gut contents. A Monte Carlo screening method is used to calibrate the model simultaneously to four experimental data sets for

  15. Earthworms enhance soil health and may also assist in improving biological insect pest suppression in pecans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior research indicated that earthworms may serve as phoretic hosts to entomopathogenic nematodes. Therefore, we hypothesized that biocontrol efficacy of entomopathogenic nematodes could be enhanced in the presence of earthworms based on increased nematode dispersal through the soil. We also hypo...

  16. Toxicity of nickel to the earthworm and the applicability of the neutral red retention assay

    E-print Network

    Hopkin, Steve

    Toxicity of nickel to the earthworm and the applicability of the neutral red retention assay JANECK of nickel on survival, growth, and reproduction of Eisenia veneta were investigated following 4 weeks of exposure to a nickel-chloride spiked loamy sand soil. The ability of a simple earthworm biomarker

  17. Earthworms as phoretic hosts for Steinernema carpocapsae and Beauveria bassiana: Implications for enhanced biological control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior research indicated that earthworms may serve as phoretic hosts to entomopathogenic nematodes. Therefore, we hypothesized that biocontrol efficacy of nematodes could be enhanced in the presence of earthworms based on increased nematode dispersal through the soil. We also hypothesized that ear...

  18. The effect of earthworms and snails in a simple plant community

    Microsoft Academic Search

    Lindsey Thompson; Chris D. Thomas; Julie M. A. Radley; Sarah Williamson; John H. Lawton

    1993-01-01

    Snails and earthworms affected the dynamics of a simple, three-species plant community, in the Ecotron controlled environment facility. Earthworms enhanced the establishment, growth and cover of the legume Trifolium dubium, both via the soil and interactions with other plant species. Worms increased soil phosphates, increased root nodulation in T. dubium, and enabled T. dubium seedlings to establish in the presence

  19. Contrasted effect of biochar and earthworms on rice growth and resource allocation in different soils

    Microsoft Academic Search

    Diana Noguera; Marco Rondón; Kam-Rigne Laossi; Valerio Hoyos; Patrick Lavelle; Maria Helena Cruz de Carvalho; Sébastien Barot

    2010-01-01

    Adding biochar to soils and maintaining high earthworm biomasses are potential ways to increase the fertility of tropical soils and the sustainability of crop production in the spirit of agroecology and ecological engineering. However, a thorough functional assessment of biochar effect on plant growth and resource allocations is so far missing. Moreover, earthworms and biochar increase mineral nutrient availability through

  20. Portable Conduction Velocity Experiments Using Earthworms for the College and High School Neuroscience Teaching Laboratory

    ERIC Educational Resources Information Center

    Shannon, Kyle M.; Gage, Gregory J.; Jankovic, Aleksandra; Wilson, W. Jeffrey; Marzullo, Timothy C.

    2014-01-01

    The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction…

  1. Potential of two epigeic and two anecic earthworm species in vermicomposting of water hyacinth

    Microsoft Academic Search

    S Gajalakshmi; E. V Ramasamy; S. A Abbasi

    2001-01-01

    The potential of two epigeic species (Eudrilus eugeniae Kinberg, and Perionyx excavatus Perrier) and two anecic species (Lampito mauritii Kinberg and Drawida willsi Michaelson) of earthworms was assessed in terms of efficiency and sustainability of vermicomposting water hyacinth (Eichhornia crassipes, Mart. Solm.). In different vermireactors, each run in duplicate with one of the four species of earthworms, and 75 g

  2. [Polycyclic musks exposure affects gene expression of specific proteins in earthworm Eisenia fetida].

    PubMed

    Chen, Chun; Liu, Xiao-wei; Zheng, Shun-an; Zhou, Qi-xing; Li, Song

    2013-05-01

    To investigate the changes in gene expression of earthworm specific proteins following long-term exposure to low-dose polycyclic musks in soil, the mRNA expression levels of the four representative protein-coding genes (HSP70, CRT, cyPA, TCTP) were examined in earthworm Eisenia fetida exposed to polycyclic musks using real-time quantitative PCR (RT-qPCR). The purpose of this study was to investigate mRNA expression profiles of test protein genes in response to sublethal galaxolide (HHCB) and tonalide (AHTN) for 28 d exposure. The analysis results of both sequence alignment and melting curves of RT-qPCR reactions showed that the selected primers were appropriately qualified for quantitative mRNA analysis. mRNA expressions of HSP70 gene were not significantly changed in Eisenia fetida exposed to low concentrations of AHTN (less than 30 microg x g(-1)) and HHCB (less than 50 microg x g(-1)). But HSP70 gene expressions were significantly down-regulated at concentrations of AHTN or HHCB equal to or greater than 30 or 50 microg x g(-1). However, up-regulation of CRT gene expressions was induced in response to all test concentrations of AHTN and HHCB. Both cyPA and TCTP gene expressions were not varied compared to control groups after 28 days of exposure. Overall, the results indicated that HSP70 and CRT genes expression patterns might be potential early molecular biomarkers for predicting the harmful exposure level and ecotoxicological effects of polycyclic musks contaminated soil. PMID:23914539

  3. Earthworm responses to different reclamation processes in post opencast mining lands during succession.

    PubMed

    Hlava, Jakub; Hlavová, Anna; Hakl, Josef; Fér, Miroslav

    2015-01-01

    This study provides earthworm population data obtained from localities with a substantial anthropogenic impact spoils. The spoil heaps were reclaimed at the end of an opencast brown coal mining period. We studied spoils reclaimed by the two most commonly used reclamation processes: forestry and agricultural. The results show the significance of the locality age and the utilized reclamation process and treatment and their effect on earthworm communities. Our data indicate that apart from soil physical and chemical properties, the reclamation process itself may also induce viability and distribution of earthworm communities. Under standardized soil properties, the changes in earthworm populations during the succession were larger within the agricultural reclamation process as opposed to the forestry reclamation process for earthworm ecological groups and individual species. PMID:25380717

  4. Effect of steaming process on new formulation and physical properties of earthworm-based fish pellets for African catfish (Clarias gariepinus).

    PubMed

    Liam, Kulaab; Zakaria, Zarina; Gunny, Ahmad Anas Nagoor; Ishak, Mohd Azlan Mohd

    2014-09-01

    Fish feed has been recognized as one of main part/unit in aquaculture industry. However, current fish feed faces few challenges in terms of health aspects and cost issues. Alternatively, new nutritional and economical/low cost formulation of fish pellets was designed by combination of earthworm powder and other economical ingredients such as fishmeal, soybean waste, rice bran and tapioca flour. The formulation was calculated using Pearson's square and optimized by One-Factor-At-Time (OFAT) method. The effect of steaming processing on the water stability, soaking experiment, protein leaching test and breaking force of the earthworm-based fish pellets was investigated. Results indicate steam pellet at 80 degrees C for 40 min has higher water stability, less protein leaching and more durable than unsteam pellets. Introduction of this new formulation of fish meal is expected to provide essential nutrient, energy and improved the quality of pellets to fuel the growth of aquaculture industry. PMID:26031027

  5. Treatment Planning Constraints to Avoid Xerostomia in Head-and-Neck Radiotherapy: An Independent Test of QUANTEC Criteria Using a Prospectively Collected Dataset

    SciTech Connect

    Moiseenko, Vitali, E-mail: vmoiseenko@bccancer.bc.ca [Department of Medical Physics, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Wu, Jonn [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Hovan, Allan [Department of Oral Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Saleh, Ziad; Apte, Aditya; Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Harrow, Stephen [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Rabuka, Carman; Muggli, Adam [Department of Oral Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Thompson, Anna [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada)

    2012-03-01

    Purpose: The severe reduction of salivary function (xerostomia) is a common complication after radiation therapy for head-and-neck cancer. Consequently, guidelines to ensure adequate function based on parotid gland tolerance dose-volume parameters have been suggested by the QUANTEC group and by Ortholan et al. We perform a validation test of these guidelines against a prospectively collected dataset and compared with a previously published dataset. Methods and Materials: Whole-mouth stimulated salivary flow data from 66 head-and-neck cancer patients treated with radiotherapy at the British Columbia Cancer Agency (BCCA) were measured, and treatment planning data were abstracted. Flow measurements were collected from 50 patients at 3 months, and 60 patients at 12-month follow-up. Previously published data from a second institution, Washington University in St. Louis (WUSTL), were used for comparison. A logistic model was used to describe the incidence of Grade 4 xerostomia as a function of the mean dose of the spared parotid gland. The rate of correctly predicting the lack of xerostomia (negative predictive value [NPV]) was computed for both the QUANTEC constraints and Ortholan et al. recommendation to constrain the total volume of both glands receiving more than 40 Gy to less than 33%. Results: Both datasets showed a rate of xerostomia of less than 20% when the mean dose to the least-irradiated parotid gland is kept to less than 20 Gy. Logistic model parameters for the incidence of xerostomia at 12 months after therapy, based on the least-irradiated gland, were D{sub 50} = 32.4 Gy and and {gamma} = 0.97. NPVs for QUANTEC guideline were 94% (BCCA data), and 90% (WUSTL data). For Ortholan et al. guideline NPVs were 85% (BCCA) and 86% (WUSTL). Conclusion: These data confirm that the QUANTEC guideline effectively avoids xerostomia, and this is somewhat more effective than constraints on the volume receiving more than 40 Gy.

  6. Avoiding the Flu

    MedlinePLUS

    ... of this page please turn Javascript on. Feature: Flu Avoiding the Flu Past Issues / Fall 2009 Table of Contents Children ... help avoid getting and passing on the flu. Influenza (Seasonal) The flu is a contagious respiratory illness ...

  7. Selective recruitment of bacteria during embryogenesis of an earthworm.

    PubMed

    Davidson, Seana K; Stahl, David A

    2008-05-01

    Earthworms of the family Lumbricidae harbor specific and stable populations of Acidovorax-like bacteria within their excretory organs, the nephridia. The symbionts of Eisenia foetida are deposited into the egg capsules during mating and the nephridia of the juveniles are colonized before they hatch. The timing and mechanisms governing bacterial recruitment and colonization are unknown for the earthworm-Acidovorax association. This study examined the process of colonization of the symbiotic organ during development of the embryos within the egg capsules. Bacteria associated with the developing embryos were visualized using in situ hybridization to bacterial cells and laser scanning confocal microscopy. Bacterial cells were associated with earthworm embryos during the earliest stages of development-the ova through to hatching. Three-dimensional examination of stages of development revealed an embryonic duct that recruits the Acidovorax-like symbiont cells. As each segment matures, Acidovorax-like symbiotic bacteria are recruited into this duct, excluding most other bacterial types, and remain there for a period of days prior to migration into the nephridium. After colonization of the nephridial ampulla, the canal remains bacteria-free. In addition to the known Acidovorax-like bacteria, multiple types of bacteria interact with the embryos externally and internally during the full course of development, and ultimately fill the gut lumen near the end of development prior to hatching. Colonization of the correct tissues by specific bacteria during differentiation and maturation of the organs must involve selective host defenses and signaling between the two partners to prevent over growth of nascent tissues. PMID:18273064

  8. Automatic Collision Avoidance Technology (ACAT)

    NASA Technical Reports Server (NTRS)

    Swihart, Donald E.; Skoog, Mark A.

    2007-01-01

    This document represents two views of the Automatic Collision Avoidance Technology (ACAT). One viewgraph presentation reviews the development and system design of Automatic Collision Avoidance Technology (ACAT). Two types of ACAT exist: Automatic Ground Collision Avoidance (AGCAS) and Automatic Air Collision Avoidance (AACAS). The AGCAS Uses Digital Terrain Elevation Data (DTED) for mapping functions, and uses Navigation data to place aircraft on map. It then scans DTED in front of and around aircraft and uses future aircraft trajectory (5g) to provide automatic flyup maneuver when required. The AACAS uses data link to determine position and closing rate. It contains several canned maneuvers to avoid collision. Automatic maneuvers can occur at last instant and both aircraft maneuver when using data link. The system can use sensor in place of data link. The second viewgraph presentation reviews the development of a flight test and an evaluation of the test. A review of the operation and comparison of the AGCAS and a pilot's performance are given. The same review is given for the AACAS is given.

  9. The Impact of Invasive Earthworm Activity on Biopolymer Character of ýDecayed Litter ý

    NASA Astrophysics Data System (ADS)

    Filley, T.; Crow, S.; Johnston, C.; McCormick, M.; Szlavecz, K.

    2007-12-01

    Over the last 400-500 years invasive European earthworm populations have ýmoved steadily into North American forests either previously devoid of ýearthworms or that contained their own native populations. This has profound ýimpacts upon litter decay and soil organic matter dynamics. To determine the ýimpact of earthworm activity on the biopolymer and stable isotope chemistry of ýlitter residues and the nature of organic carbon moved to the soil profile we ýanalyzed tulip poplar leaves from a multi-year addition experiment in open ýsurface decay litter and litter bag decay experiments, as well as the associated ýsoils among forest plots that varied in non-native earthworm density and ýbiomass. The chemical alteration of biopolymers was tracked with FTIR ýspectroscopy, 13C-TMAH thermochemolysis, alkaline CuO extraction, and stable ýisotope mass spectrometry. Earthworm activity resulted in residues and soil ýparticulate organic matter depleted in cuticular aliphatic components and ýpolyphenols but highly enriched in ether-linked lignin with respect to initial litter ýmaterial. Decay in low earthworm abundance plots, as well as all experiments ýwith earthworm-excluding litter bags, resulted in enrichment in cutin aliphatics ýand only minor increases in ether linked lignin phenols which was also reflected ýin the soils below the amendments. Additionally, the stable carbon and nitrogen ýisotope composition of tulip poplar residues became isotopically distinct. The ýresults from litter bag decays were only reflective of the chemistry at sites with ývery low earthworm abundances. ý

  10. Concentration of cadmium in Coturnix quail fed earthworms

    SciTech Connect

    Stoewsand, G.S.; Bache, C.A.; Gutenmann, W.H.; Lisk, D.J.

    1986-01-01

    Earthworms (Lumbriscus terrestris), collected from soils in southern Ontario, Canada, that had no previous history of cadmium application, contained 3 ppm cadmium. They were fed to Coturnix quail as 60% dry weight of their diet for 63 d to examine the extent of deposition of native cadmium. Cadmium in kidney, liver, and excreta was greatly elevated above that of birds fed a control diet without worms. No increase in the level of cadmium in eggs was found. The factors affecting the association of cadmium in soils and worms and their assimilation and possible toxic effects in foraging birds are discussed.

  11. Polychlorinated biphenyls (PCBs) depress allogeneic natural cytotoxicity by earthworm coelomocytes

    SciTech Connect

    Suzuki, M.M.; Cooper, E.L. [Univ. of California, Los Angeles, CA (United States). Lab. of Comparative Immunology; Eyambe, G.S.; Goven, A.J.; Fitzpatrick, L.C. [Univ. of North Texas, Denton, TX (United States). Dept. of Biological Sciences; Venables, B.J. [Univ. of North Texas, Denton, TX (United States). Dept. of Biological Sciences]|[TRAC Labs., Denton, TX (United States)

    1995-10-01

    Coelomocytes of the earthworm Lumbricus terrestris caused significant spontaneous allogeneic cytotoxicity in a 24-h trypan blue assay, but not in an assay using lactate dehydrogenase (LDH) release. Allogeneic cytotoxicity assays using cells from worms exposed to polychlorinated biphenyls (PCBs) suggest that PCBs can suppress a natural killing (NK-like) reaction. The implications of this work are twofold: understanding the evolution of natural killing (NK-like) activity and providing preliminary information on how spontaneous killing, a component of cellular immunity, may be compromised by pollutants.

  12. Metallothionein gene expression differs in earthworm populations with different exposure history.

    PubMed

    Mustonen, M; Haimi, J; Väisänen, A; Knott, K E

    2014-11-01

    Metals are persistent pollutants in soils that can harm soil organisms and decrease species diversity. Animals can cope with metal contamination with the help of metallothioneins, small metal-binding proteins involved in homeostasis and detoxification of metals. We studied the expression of metallothionein with qPCR in a small, epigeic earthworm, Dendrobaena octaedra. We compared expression patterns and metal body content in earthworms collected from two sites with different metal contamination histories: Harjavalta, contaminated by a Cu-Ni smelter operational for over 50 years, and Jyväskylä, an uncontaminated site. Earthworms from both sites were also experimentally exposed to different concentrations of Cu (control, 50, 100 or 200 mg/kg) or Zn (control, 75, 150 or 300 mg/kg) for 7, 14 or 28 days to determine if there is a time related dose-response in gene expression. Population comparison showed that metallothionein expression was higher in earthworms from the contaminated site. In the exposure experiment, exposure time affected expression, but only in the earthworms from the uncontaminated site, suggesting that there is a delay in the metallothionein response of earthworms in this population. In contrast, earthworms from the contaminated site showed higher and constant levels of metallothionein expression at all exposure concentrations and durations. The constant metallothionein expression in earthworms from the contaminated site suggests that inducibility of metallothionein response could be lost in earthworms with metal exposure history. Adaptation of D. octaedra to metal exposure could explain the differences between the populations and explain the persistence of this species in contaminated forest soils. PMID:25179588

  13. Geochemistry and Chemical Weathering in Soils along an Earthworm Invasion Gradient

    NASA Astrophysics Data System (ADS)

    Resner, K.; Yoo, K.; Aufdenkampe, A. K.; Hale, C.; Sebestyen, S. D.

    2010-12-01

    One of the central tenets in geomorphology is that a chemical denudation rate is limited by the total denudation rate, which controls how fast minerals are exposed to reactive environments of the earth’s surface. Though the mineral supply rate has been routinely tied to tectonic uplifts, in soil mantled landscapes, organisms such as earthworms may also significantly contribute to exposing minerals to varying geochemical environments and thus altering chemical denudation rates of the landscapes they inhabit through mineral translocation. In glaciated parts of North America, many forests evolved without native earthworms, since the last glacial retreat, until they were invaded by exotic earthworm species that arrived with agriculture, recreational fishing, and logging. Therefore, an earthworm invasion chronosequence in northern Minnesota--the focus of this ongoing study--provides an ideal natural laboratory to quantitatively study how burrowing organisms, by mixing soils, contribute to chemically denuding the landscapes. We are currently determining the inorganic chemistry of soils along a ~200 meter long transect that includes pre earthworm invasion soils as well as soils populated with several earthworm species with different burrowing habits. Additionally, six soils pits along the transect are densely installed with lysimeters, piezometers, and gas sampling tubes. The soils’ elemental chemistry profiles show that earthworms have significantly relocated minerals vertically, which is consistent with the 210Pb activity profiles determined with gamma spectroscopy. Major elements, depending on their solubility, biological demands, and susceptibility to be complexed with organic matter, respond to the enhanced mixing rates in different ways. To constrain the impacts of earthworm burrowing on chemical denudation, we are also measuring cations, anions, and alkalinity in the water samples collected with the lysimeters and piezometers. Ultimately, the soil and water chemistry and 210Pb activities, together with ongoing monitoring of earthworms’ species composition and population density, will allow us to understand how and to what degree the soil mixing organisms affect chemical denudation of landscapes, which is central to our efforts in finding the topographic signatures of life.

  14. Joint toxicity of chlorpyrifos, atrazine, and cadmium at lethal concentrations to the earthworm Eisenia fetida.

    PubMed

    Yang, Guiling; Chen, Chen; Wang, Yanhua; Cai, Leiming; Kong, Xiangzhen; Qian, Yongzhong; Wang, Qiang

    2015-06-01

    Contaminants in the environment often occur as complex mixtures, and their combined effect may exhibit toxicity to organisms. Risk assessments based on individual components tend to underestimate the effects associated with toxic action of mixtures. Toxicity studies on chemical mixtures are urgently required to assess their potential combined toxicities. The combination index (CI)-isobologram method was used to study chemical interactions to determine the nature of toxicological interactions of two pesticides chlorpyrifos and atrazine and a heavy metal cadmium toward earthworm Eisenia fetida by artificial soil and filter paper acute toxicity tests. The results showed that the binary mixture of chlorpyrifos and atrazine was antagonistic toward E. fetida at all f a levels in an artificial soil test. The combination of atrazine and Cd exhibited a slight degree of synergism throughout the exposure range, while chlorpyrifos plus Cd combination led to dual antagonistic/synergistic behavior. The nature of binary combinations in filter paper displayed opposite interaction to that in the artificial soil test, and the toxicity of ternary mixtures was not significantly synergistic than their binaries. The combination index (CI)-isobologram equation method could determine the interaction types for a series of effect levels of three chemicals in binary and ternary combinations in two types of acute earthworm tests. However, the nature of these interactions was not uniform along the f a level range in any of the two tests. Bioavailability, the nature of toxicological interaction, and the test organism need to be considered for understanding exposures and chemical measures. The synergistic effect for the particular binary combination suggests that a potential risk associated with the co-occurrence of these pollutants may still exist, which may have implications in risk assessment for the terrestrial environment. The combined effects between different contaminants might be influenced by the category of chemical, as well as the bioassay procedures. More studies of combined toxicities among these contaminants in the terrestrial environment should be conducted to identify the mixtures exhibiting synergistic pattern of interactions. PMID:25595933

  15. Testing the credibility, feasibility and acceptability of an optimised behavioural intervention (OBI) for avoidant chronic low back pain patients: protocol for a randomised feasibility study

    PubMed Central

    2013-01-01

    Background Chronic back pain continues to be a costly and prevalent condition. The latest NICE guidelines issued in 2009 state that for patients with persistent back pain (of between six weeks and twelve months duration), who are highly distressed and/or disabled and for whom exercise, manual therapy and acupuncture has not been beneficial, the evidence supports a combination of around 100 hours of combined physical and psychological treatment. This is costly, and may prove unacceptable to many patients. A key recommendation of these guidelines was for further randomised controlled trials (RCTs) of psychological treatment and to target treatment to specific sub-groups of patients. Recent trials that have included psychological interventions have shown only moderate improvement at best, and results are not maintained long term. There is therefore a need to test theoretically driven interventions that focus on specific high-risk sub-groups, in which the intervention is delivered at full integrity against a credible control. Methods/design A feasibility study of a pragmatic randomised controlled trial comparing psychologist-delivered Contextual Cognitive Behavioural Therapy (CCBT) against Treatment As Usual (TAU) physiotherapy delivered by physiotherapists for the treatment of chronic lower back pain in ‘avoidant’ patients. Ninety-two patients referred for physiotherapy will be recruited and randomised on a 1:1 basis to receive CCBT or TAU. Treatment groups will be balanced by centre and pain interference score. Primary outcomes include assessing the credibility and acceptability of the intervention, and to demonstrate proof of principle through a greater change in pain acceptance in the CCBT arm, measured by the Acceptance and Action –II and the Chronic Pain Acceptance questionnaires. In addition, the feasibility of carrying out a full trial will be explored with reference to recruitment and follow-up rates including the assessment of the burden of outcome measure completion. Secondary patient outcomes include disability, pain, fear of movement, mood, quality of life, and global recovery. Outcomes are measured at three and six months post-randomisation. Discussion This paper details the rationale, design, therapist training system and recruitment methods to be used in a feasibility study which will inform the design and efficient implementation of a future definitive RCT. Trial registration ISRCTN43733490 PMID:23764140

  16. Profiles of organochlorine pesticides in earthworms from urban leisure areas of Beijing, China.

    PubMed

    Li, Xing-Hong; Wang, Xi-Zhi; Wang, Wei; Jiang, Xiang-Ning; Xu, Xiao-Bai

    2010-04-01

    In this study, organochlorine pesticides (HCHs and DDTs) in earthworm and soil contacted closely with it were determined for the purpose of the risk assessment of chemicals in the urban leisure environment. The level of total hexachlorocyclohexanes and (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in earthworms was 0.6500-44.78 ng g(-1) and 18.97-1.112 x 104 ng g(-1), respectively. Absolutely high levels of DDT and its metabolites in earthworm and correlative soils samples, and the bioaccumulation factor (BAF) of DDTs probably presents certain risk to the higher trophic organisms through its food chain, especially birds. PMID:20238098

  17. Municipal solid waste management through vermicomposting employing exotic and local species of earthworms.

    PubMed

    Kaviraj; Sharma, Satyawati

    2003-11-01

    A comparative study was conducted between exotic and local (epigeic--Eisenia fetida and anaecic--Lempito mauritii, respectively) species of earthworms for the evaluation of their efficacy in vermicomposting of municipal solid waste (MSW). Vermicomposting of MSW for 42 days resulted in significant difference between the two species in their performance measured as loss in total organic carbon, carbon-nitrogen ratio (C:N) and increase in total Kjeldahl nitrogen, electrical conductivity and total potassium and weight loss of MSW. The change in pH and increase in number of earthworms and cocoons and weight of earthworms were non-significant. PMID:12895560

  18. Foraging bats avoid noise.

    PubMed

    Schaub, Andrea; Ostwald, Joachim; Siemers, Björn M

    2008-10-01

    Ambient noise influences the availability and use of acoustic information in animals in many ways. While much research has focused on the effects of noise on acoustic communication, here, we present the first study concerned with anthropogenic noise and foraging behaviour. We chose the greater mouse-eared bat (Myotis myotis) as a model species because it represents the especially vulnerable group of gleaning bats that rely on listening for prey rustling sounds to find food (i.e. 'passive listening'). In a choice experiment with two foraging compartments, we investigated the influence of background noise on foraging effort and foraging success. We tested the hypotheses that: (1) bats will avoid foraging areas with particularly loud background noise; and (2) the frequency-time structure of the noise will determine, in part, the degree to which it deters bats. We found a clear effect of the type of noise on the allocation of foraging effort to the compartments and on the distribution of prey capture events. When playing back silence, the bats made equal use of and were equally successful in both compartments. In the other three treatments (where a non-silent sound was played back), the bats avoided the playback compartment. The degree to which the background noise deterred bats from the compartment increased from traffic noise to vegetation movement noise to broadband computer-generated noise. Vegetation noise, set 12 dB below the traffic noise amplitude, had a larger repellent effect; presumably because of its acoustic similarity with prey sounds. Our experimental data suggest that foraging areas very close to highways and presumably also to other sources of intense, broadband noise are degraded in their suitability as foraging areas for such 'passive listening' bats. PMID:18805817

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

    PubMed

    Chiochetta, Claudete G; Radetski, Marilice R; Corręa, 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. PMID:23114837

  20. Generalization of socially transmitted and instructed avoidance

    PubMed Central

    Cameron, Gemma; Schlund, Michael W.; Dymond, Simon

    2015-01-01

    Excessive avoidance behavior, in which an instrumental action prevents an upcoming aversive event, is a defining feature of anxiety disorders. Left unchecked, both fear and avoidance of potentially threatening stimuli may generalize to perceptually related stimuli and situations. The behavioral consequences of generalization mean that aversive learning experiences with specific threats may lead to the inference that classes of related stimuli are threatening, potentially dangerous, and need to be avoided, despite differences in physical form. Little is known however about avoidance generalization in humans and the learning pathways by which it may be transmitted. In the present study, we compared two pathways to avoidance—instructions and social observation—on subsequent generalization of avoidance behavior, fear expectancy and physiological arousal. Participants first learned that one cue was a danger cue (conditioned stimulus, CS+) and another was a safety cue (CS?). Groups were then either instructed that a simple avoidance response in the presence of the CS+ cancelled upcoming shock (instructed-learning group) or observed a short movie showing a demonstrator performing the avoidance response to prevent shock (observational-learning group). During generalization testing, danger and safety cues were presented along with generalization stimuli that parametrically varied in perceptual similarity to the CS+. Reinstatement of fear and avoidance was also tested. Findings demonstrate, for the first time, generalization of socially transmitted and instructed avoidance: both groups showed comparable generalization gradients in fear expectancy, avoidance behavior and arousal. Return of fear was evident, suggesting that generalized avoidance remains persistent following extinction testing. The utility of the present paradigm for research on avoidance generalization is discussed.

  1. The binding interactions of imidacloprid with earthworm fibrinolytic enzyme

    NASA Astrophysics Data System (ADS)

    Wang, Yan-Qing; Zhang, Hong-Mei; Chen, Tao

    2014-08-01

    In this paper, several studies were conducted to elucidate the binding mechanism of earthworm fibrinolytic enzyme (EFE) with imidocloprid (IMI) by using theoretical calculation, fluorescence, UV-vis, circular dichroism spectroscopy and an enzymatic inhibition assay. The spectral data showed that the binding interactions existed between IMI and EFE. The binding constants, binding site, thermodynamic parameters and binding forces were analyzed in detail. The results indicate a single class of binding sites for IMI in EFE and that this binding interaction is a spontaneous process with the estimated enthalpy and entropy changes being 2.195 kJ mol-1 and 94.480 J mol-1 K-1, respectively. A single class of binding site existed for IMI in EFE. The tertiary or secondary structure of EFE was partly destroyed by IMI. The visualized binding details were also exhibited by the theoretical calculation and the results indicated that the interaction between IMI and Phe (Tyr, or Trp) or EFE occurred. Combining the experimental data with the theoretical calculation data, we showed that the binding forces between IMI and EFE were mainly hydrophobic force accompanied by hydrogen binding, and ?-? stacking. In addition, IMI did not obviously influence the activity of EFE. In a word, the above analysis offered insights into the binding mechanism of IMI with EFE and could provide some important information for the molecular toxicity of IMI for earthworms.

  2. Harm Avoidance and Cerebral Infarction

    PubMed Central

    Wilson, Robert S.; Boyle, Patricia A.; Levine, Steven R.; Yu, Lei; Hoganson, George M.; Buchman, Aron S.; Schneider, Julie A.; Bennett, David A.

    2014-01-01

    Objective Harm avoidance, a trait indicative of behavioral inhibition, is associated with disability and dementia in old age, but the basis of these associations is uncertain. We test the hypothesis that higher level of harm avoidance is associated with increased likelihood of cerebral infarction. Methods Older persons without dementia completed a standard measure of harm avoidance. During a mean of 3.5 years of follow-up, 257 (of 1,082) individuals died of whom 206 (80%) underwent brain autopsy. Number of chronic cerebral infarcts (microscopic plus gross; expressed as 0,1, or >1) was assessed on neuropathologic examination, completed in 192 individuals at the time of analyses. Results On postmortem examination, chronic cerebral infarcts were found in 89 (42 with 1, 47 with >1). Higher harm avoidance was associated with higher likelihood of infarcts (odds ratio = 1.083, 95% confidence interval 1.040–1.128). A moderately high level of the trait (score=17, 75th percentile) was associated with a 2.4-fold increase in the likelihood of infarction compared to a moderately low level of the trait (score = 6, 25th percentile). These associations persisted in models that controlled for other cardiovascular risk factors. Conclusion Higher level of the harm avoidance trait may be a risk factor for cerebral infarction. PMID:24364391

  3. Cadmium effect on the structure of supra- and subpharyngeal ganglia and the neurosecretory processes in earthworm Dendrobaena veneta (Rosa).

    PubMed

    Siekierska, Ewa

    2003-01-01

    Cadmium effects on the supra- and subpharyngeal ganglia, neurosecretion and RNA content in the neurosecretory cells were tested in earthworms Dendrobaena veneta exposed to 10 and 50 mg Cd kg(-1) in soil after 20 days of the experiment. Accumulation of cadmium in the ganglia of nervous system was also measured using AAS method. Cadmium was accumulated in the nervous system. The accumulated amount was proportional to Cd soil concentration and the exposure time. A considerable fall in neurosecretion and RNA content in the neurosecretory cells and neurosecretion in the neuropile (the axons) of both tested ganglia was induced by 50 mg Cd kg(-1). It seemed that neurosecretion synthesis and its axonal transport could be suppressed. Cadmium caused degenerative changes as vacuolization of the neurosecretory cells and neuropile in both tested ganglia. PMID:12860099

  4. FUNCTIONAL CONNECTIONS ARE ESTABLISHED BETWEEN GIANT NERVE FIBERS IN GRAFTED EARTHWORMS

    EPA Science Inventory

    Giant fiber interconnections were examined in successful grafts between two posterior portions of earthworms (Eisenia foetida). Electrophysiological and histological results indicated that cell-specific interanimal connections were formed between the medial giant fibers (MGF) in ...

  5. Verminephrobacter eiseniae type IV pili and flagella are required to colonize earthworm nephridia

    PubMed Central

    Dulla, Glenn F J; Go, Ruth A; Stahl, David A; Davidson, Seana K

    2012-01-01

    The bacterial symbiont Verminephrobacter eiseniae colonizes nephridia, the excretory organs, of the lumbricid earthworm Eisenia fetida. E. fetida transfers V. eisenia into the egg capsule albumin during capsule formation and V. eiseniae cells migrate into the earthworm nephridia during embryogenesis, where they bind and persist. In order to characterize the mechanistic basis of selective tissue colonization, methods for site-directed mutagenesis and colonization competence were developed and used to evaluate the consequences of individual gene disruptions. Using these newly developed tools, two distinct modes of bacterial motility were shown to be required for V. eiseniae colonization of nascent earthworm nephridia. Flagella and type IV pili mutants lacked motility in culture and were not able to colonize embryonic earthworms, indicating that both twitching and flagellar motility are required for entrance into the nephridia. PMID:22170422

  6. Verminephrobacter eiseniae type IV pili and flagella are required to colonize earthworm nephridia.

    PubMed

    Dulla, Glenn F J; Go, Ruth A; Stahl, David A; Davidson, Seana K

    2012-06-01

    The bacterial symbiont Verminephrobacter eiseniae colonizes nephridia, the excretory organs, of the lumbricid earthworm Eisenia fetida. E. fetida transfers V. eisenia into the egg capsule albumin during capsule formation and V. eiseniae cells migrate into the earthworm nephridia during embryogenesis, where they bind and persist. In order to characterize the mechanistic basis of selective tissue colonization, methods for site-directed mutagenesis and colonization competence were developed and used to evaluate the consequences of individual gene disruptions. Using these newly developed tools, two distinct modes of bacterial motility were shown to be required for V. eiseniae colonization of nascent earthworm nephridia. Flagella and type IV pili mutants lacked motility in culture and were not able to colonize embryonic earthworms, indicating that both twitching and flagellar motility are required for entrance into the nephridia. PMID:22170422

  7. Taxonomic composition and physiological and biochemical properties of bacteria in the digestive tracts of earthworms

    NASA Astrophysics Data System (ADS)

    Byzov, B. A.; Tikhonov, V. V.; Nechitailo, T. Yu.; Demin, V. V.; Zvyagintsev, D. G.

    2015-03-01

    Several hundred bacterial strains belonging to different taxa were isolated and identified from the digestive tracts of soil and compost earthworms. Some physiological and biochemical properties of the bacteria were characterized. The majority of intestinal bacteria in the earthworms were found to be facultative anaerobes. The intestinal isolates as compared to the soil ones had elevated activity of proteases and dehydrogenases. In addition, bacteria associated with earthworms' intestines are capable of growth on humic acids as a sole carbon source. Humic acid stimulated the growth of the intestinal bacteria to a greater extent than those of the soil ones. In the digestive tracts, polyphenol oxidase activity was found. Along with the data on the taxonomic separation of the intestinal bacteria, the features described testified to the presence of a group of bacteria in the earthworms intestines that is functionally characteristic and is different from the soil bacteria.

  8. Effects of earthworms on physicochemical properties and microbial profiles during vermicomposting of fresh fruit and vegetable wastes.

    PubMed

    Huang, Kui; Li, Fusheng; Wei, Yongfen; Fu, Xiaoyong; Chen, Xuemin

    2014-10-01

    This study aimed to investigate the effect of earthworms on physicochemical and microbial properties during vermicomposting of fresh fruit and vegetable wastes (FVW) by contrasting two decomposing systems of FVW with and without earthworms for 5weeks. Compared to control treatment (without earthworms), vermicomposting treatment resulted in a rapid decrease of electrical conductivity and losses of total carbon and nitrogen from the 2nd week. Quantitative PCR displayed that earthworms markedly enhanced bacterial and fungal densities, showing the higher values than control, during the whole decomposition process. In addition, denaturing gradient gel electrophoresis combined with sequencing analysis revealed that earthworms pronouncedly modified bacterial and fungal community structures, through broadening the community diversities of Actinobacteria, Bacteroidetes, Proteobacteria, and Ascomycotina. These results suggest that the presence of earthworms promoted the activity and population of bacteria and fungi, and modified their communities, thus altering the decomposition pathway of fresh FVW. PMID:25118152

  9. Emission of Methane by Eudrilus eugeniae and Other Earthworms from Brazil

    PubMed Central

    Depkat-Jakob, Peter S.; Hunger, Sindy; Schulz, Kristin; Brown, George G.; Tsai, Siu M.

    2012-01-01

    Earthworms emit denitrification-derived nitrous oxide and fermentation-derived molecular hydrogen. The present study demonstrated that the earthworm Eudrilus eugeniae, obtained in Brazil, emitted methane. Other worms displayed a lesser or no capacity to emit methane. Gene and transcript analyses of mcrA (encoding the alpha subunit of methyl-CoM reductase) in gut contents of E. eugeniae suggested that Methanosarcinaceae, Methanobacteriaceae, and Methanomicrobiaceae might be associated with this emission. PMID:22344639

  10. Effects of earthworms on soil enzyme activity in an organic residue amended rice–wheat rotation agro-ecosystem

    Microsoft Academic Search

    Jun Tao; Bryan Griffiths; Shujie Zhang; Xiaoyun Chen; Manqiang Liu; Feng Hu; Huixin Li

    2009-01-01

    The effect of earthworms on soil hydrolases (protease, urease, invertase, and alkaline phosphatase) and dehydrogenase activities was investigated in maize residue amended rice–wheat rotation agro-ecosystem. Experimental plots in the rotation had five treatments, i.e. incorporation or mulching of maize residues with or without added earthworms and an untreated control. The application of maize residues to soil without earthworms significantly enhanced

  11. Avoiding Statistical Mistakes

    ERIC Educational Resources Information Center

    Strasser, Nora

    2007-01-01

    Avoiding statistical mistakes is important for educators at all levels. Basic concepts will help you to avoid making mistakes using statistics and to look at data with a critical eye. Statistical data is used at educational institutions for many purposes. It can be used to support budget requests, changes in educational philosophy, changes to…

  12. [Effects of inoculating earthworm on the seed yield and its oil content of winter oilseed rape].

    PubMed

    Zhang, Shu-Jie; Zhang, Chun-Lei

    2011-06-01

    A field experiment was conducted to study the effects of inoculating earthworm (Metaphire guillelmi) on the yield components, seed yield, and seed oil content of winter oilseed rape (Brassica napus L. cv. Zhongshuang 9). Inoculating earthworm increased the primary branch numbers per plant, main raceme pod numbers per plant, seed numbers per pod, and 1000-seeds weight, but the effect was not significant. However, comparing with the control, inoculating earthworm increased the pod number per plant, seed yield per plant, and seed yield of whole plot significantly, with the increment being 36.7%, 46.5%, and 29.7%, respectively, which could be related to the promotion effect of earthworm on the plant growth and its nitrogen uptake at vegetative growth stage. After the inoculation with earthworm, the seed oil content somewhat decreased, but, owing to the significant increase of seed yield under the effect of earthworm, both the oil production per plant and the oil production of whole plot increased significantly by 37.4% and 21.0%, respectively, compared with the control. PMID:21941751

  13. Invasive earthworms interact with abiotic conditions to influence the invasion of common buckthorn (Rhamnus cathartica).

    PubMed

    Roth, Alexander M; Whitfeld, Timothy J S; Lodge, Alexandra G; Eisenhauer, Nico; Frelich, Lee E; Reich, Peter B

    2015-05-01

    Common buckthorn (Rhamnus cathartica L.) is one of the most abundant and ecologically harmful non-native plants in forests of the Upper Midwest United States. At the same time, European earthworms are invading previously glaciated areas in this region, with largely anecdotal evidence suggesting they compound the negative effects of buckthorn and influence the invasibility of these forests. Germination and seedling establishment are important control points for colonization by any species, and manipulation of the conditions influencing these life history stages may provide insight into why invasive species are successful in some environments and not others. Using a greenhouse microcosm experiment, we examined the effects of important biotic and abiotic factors on the germination and seedling establishment of common buckthorn. We manipulated light levels, leaf litter depth and earthworm presence to investigate the independent and interactive effects of these treatments on buckthorn establishment. We found that light and leaf litter depth were significant predictors of buckthorn germination but that the presence of earthworms was the most important factor; earthworms interacted with light and leaf litter to increase the number and biomass of buckthorn across all treatments. Path analysis suggested both direct and moisture-mediated indirect mechanisms controlled these processes. The results suggest that the action of earthworms may provide a pathway through which buckthorn invades forests of the Upper Midwest United States. Hence, researchers and managers should consider co-invasion of plants and earthworms when investigating invasibility and creating preemptive or post-invasion management plans. PMID:25481818

  14. Earthworms Dilong: Ancient, Inexpensive, Noncontroversial Models May Help Clarify Approaches to Integrated Medicine Emphasizing Neuroimmune Systems

    PubMed Central

    Cooper, Edwin L.; Balamurugan, Mariappan; Huang, Chih-Yang; Tsao, Clara R.; Heredia, Jesus; Tommaseo-Ponzetta, Mila; Paoletti, Maurizio G.

    2012-01-01

    Earthworms have provided ancient cultures with food and sources of medicinal cures. Ayurveda, traditional Chinese medicine (TCM), and practices in Japan, Vietnam, and Korea have focused first on earthworms as sources of food. Gradually fostering an approach to potential beneficial healing properties, there are renewed efforts through bioprospecting and evidence-based research to understand by means of rigorous investigations the mechanisms of action whether earthworms are used as food and/or as sources of potential medicinal products. Focusing on earthworms grew by serendipity from an extensive analysis of the earthworm's innate immune system. Their immune systems are replete with leukocytes and humoral products that exert credible health benefits. Their emerging functions with respect to evolution of innate immunity have long been superseded by their well-known ecological role in soil conservation. Earthworms as inexpensive, noncontroversial animal models (without ethical concerns) are not vectors of disease do not harbor parasites that threaten humans nor are they annoying pests. By recognizing their numerous ecological, environmental, and biomedical roles, substantiated by inexpensive and more comprehensive investigations, we will become more aware of their undiscovered beneficial properties. PMID:22888362

  15. Soil bioturbation by earthworms and plant roots- mechanical and energetic considerations

    NASA Astrophysics Data System (ADS)

    Ruiz, S.; Or, D.; Schymanski, S. J.

    2014-12-01

    Soil structure is a key factor shaping hydrological and ecological functions including water storage, deep recharge and plant growth. Compaction adversely impacts soil ecosystem services over extended periods (years to decades) until structure and functionality are restored. An important class of soil structural restoration processes are related to biomechanical activity associated with borrowing of earthworms and root proliferation in impacted soils. This study employs a new biomechanical model to estimate stresses required for earthworm and plant root bioturbation under different conditions and the mechanical energy required. We consider steady state plastic cavity expansion to determine burrowing pressures of earthworms and plant roots as linked with models for cone penetration required for initial burrowing into soil volumes. We use earthworm physical and ecological parameters (e.g., population density, burrowing rate, and burrowing behavior) to convert mechanical deformation to estimation of energy and soil organic carbon (energy source for earthworms). Results illustrate a reduction in strain energy with increasing water content and trade-offs between pressure and energy investment for various root and earthworm geometries and soil hydration. The study provides a quantitative framework for estimating energy costs of bioturbation in terms of soil organic carbon or plant assimilates and delineates mechanical and hydration conditions that promote or constrain such activities.

  16. Further records of non-cryptic New Zealand earthworms

    PubMed Central

    Blakemore, Robert

    2011-01-01

    Abstract Current descriptions add natives Aporodrilus aotea sp. n., Aporodrilus ponga sp. n. and Notoscolex repanga sp. n., plus new exotic records to the numbers of megadrile earthworms known from New Zealand, which are now raised from 193 to 222 species in five families, viz: Acanthodrilidae, Octochaetidae and Megascolecidae, plus Lumbricidae and Glossoscolecidae for exotics. Overlooked spermathecal diverticula have been located for Notoscolex equestris Benham, 1942 and for Megascolex animae Lee, 1959 and non-tubular prostrates were misconstrued as tubular in Megascolides tasmani Lee, 1959. Of these latter three species, a lectotype is designated for Notoscolex equestris and holotypes of the other two are briefly redescribed. Whereas Megascolides tasmani now belongs in Notoscolex Fletcher, 1887 and Megascolides animae belongs in Anisochaeta Beddard, 1890, further lack of dorsal pores in Notoscolex equestris as with Notoscolex esculentus (Benham, 1904) and Notoscolex mortenseni (Michaelsen, 1924) newly qualifies all three as additional combs. novae in primarily Tasmanian genus Aporodrilus Blakemore, 2000. PMID:22303118

  17. 870 VOLUME 24 NUMBER 8 AUGUST 2006 NATURE BIOTECHNOLOGY Another strategy is to avoid placing all your eggs in the testing labora-

    E-print Network

    Cai, Long

    of the sales are for routine standard-of-care cholesterol tests,urine analysis, blood work with traditional your eggs in the testing labora- tories'baskets.For example,Cepheid (Sunnyvale,CA,USA) first moved there is a premium on a rapid response. Encouraging adoption of a test is only part of the battle, however. The other

  18. Avoiding Computer Viruses.

    ERIC Educational Resources Information Center

    Rowe, Joyce; And Others

    1989-01-01

    The threat of computer sabotage is a real concern to business teachers and others responsible for academic computer facilities. Teachers can minimize the possibility. Eight suggestions for avoiding computer viruses are given. (JOW)

  19. Operational Collision Avoidance

    NASA Technical Reports Server (NTRS)

    Guit, Bill

    2015-01-01

    This presentation will describe the early days of the EOS Aqua and Aura operational collision avoidance process. It will highlight EOS debris avoidance maneuvers, EOS high interest event statistic and A-Train systematic conjunctions and conclude with future challenges. This is related to earlier e-DAA (tracking number 21692) that an abstract was submitted to a different conference. Eric Moyer, ESMO Deputy Project Manager has reviewed and approved this presentation on May 6, 2015

  20. Evolution of the tripartite symbiosis between earthworms, Verminephrobacter and Flexibacter-like bacteria

    PubMed Central

    Mřller, Peter; Lund, Marie B.; Schramm, Andreas

    2015-01-01

    Nephridial (excretory organ) symbionts are widespread in lumbricid earthworms and the complexity of the nephridial symbiont communities varies greatly between earthworm species. The two most common symbionts are the well-described Verminephrobacter and less well-known Flexibacter-like bacteria. Verminephrobacter are present in almost all lumbricid earthworms, they are species-specific, vertically transmitted, and have presumably been associated with their hosts since the origin of lumbricids. Flexibacter-like symbionts have been reported from about half the investigated earthworms; they are also vertically transmitted. To investigate the evolution of this tri-partite symbiosis, phylogenies for 18 lumbricid earthworm species were constructed based on two mitochondrial genes, NADH dehydrogenase subunit 2 (ND2) and cytochrome c oxidase subunit I (COI), and compared to their symbiont phylogenies based on RNA polymerase subunit B (rpoB) and 16S rRNA genes. The two nephridial symbionts showed markedly different evolutionary histories with their hosts. For Verminephrobacter, clear signs of long-term host-symbiont co-evolution with rare host switching events confirmed its ancient association with lumbricid earthworms, likely dating back to their last common ancestor about 100 million years (MY) ago. In contrast, phylogenies for the Flexibacter-like symbionts suggested an ability to switch to new hosts, to which they adapted and subsequently became species-specific. Putative co-speciation events were only observed with closely related host species; on that basis, this secondary symbiosis was estimated to be minimum 45 MY old. Based on the monophyletic clustering of the Flexibacter-like symbionts, the low 16S rRNA gene sequence similarity to the nearest described species (<92%) and environmental sequences (<94.2%), and the specific habitat in the earthworm nephridia, we propose a new candidate genus for this group, Candidatus Nephrothrix. PMID:26074907

  1. Integration of Weather Avoidance and Traffic Separation

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria C.; Chamberlain, James P.; Wilson, Sara R.

    2011-01-01

    This paper describes a dynamic convective weather avoidance concept that compensates for weather motion uncertainties; the integration of this weather avoidance concept into a prototype 4-D trajectory-based Airborne Separation Assurance System (ASAS) application; and test results from a batch (non-piloted) simulation of the integrated application with high traffic densities and a dynamic convective weather model. The weather model can simulate a number of pseudo-random hazardous weather patterns, such as slow- or fast-moving cells and opening or closing weather gaps, and also allows for modeling of onboard weather radar limitations in range and azimuth. The weather avoidance concept employs nested "core" and "avoid" polygons around convective weather cells, and the simulations assess the effectiveness of various avoid polygon sizes in the presence of different weather patterns, using traffic scenarios representing approximately two times the current traffic density in en-route airspace. Results from the simulation experiment show that the weather avoidance concept is effective over a wide range of weather patterns and cell speeds. Avoid polygons that are only 2-3 miles larger than their core polygons are sufficient to account for weather uncertainties in almost all cases, and traffic separation performance does not appear to degrade with the addition of weather polygon avoidance. Additional "lessons learned" from the batch simulation study are discussed in the paper, along with insights for improving the weather avoidance concept. Introduction

  2. Cadmium effect on the ovarian structure in earthworm Dendrobaena veneta (Rosa).

    PubMed

    Siekierska, Ewa; Urba?ska-Jasik, Danuta

    2002-01-01

    Cadmium effects on the ovary structure and oocytes were tested in earthworms Dendrobaena veneta exposed to 10 and 50 mg Cd kg(-1) in soil after 10 and 20 days of the experiment. In both experimental doses cadmium caused damage to the structure of the ovary but the effects were different in each group. At 10 mg Cd kg(-1) concentration in soil, young stages of oocytes and trophocytes were most sensitive to cadmium deleterious effects whereas somatic cells in the ovarian stroma were only slightly affected. Cadmium. at a concentration of 50 mg Cd kg(-1) in soil caused most damage in the somatic cells leading to the occurrence of unnaturally swollen elements and desmosomes destruction. At both experimental concentrations cadmium induced degenerative changes in cell nuclei and an increase in number of cell organelles (RER and Golgi complex elements) in the cytoplasm of oocytes and trophocytes. These also proved to be more active. No ultrastructural changes were manifested in oogonia. In both experimental groups degenerative changes occurred as early as after 10 days of Cd exposure. PMID:12395841

  3. Changes in chemistry and aggregation of a california forest soil worked by the earthworm Argilophilus papillifer eisen (megascolecidae)

    Microsoft Academic Search

    John G. McColl

    1998-01-01

    Little is known about the functional significance of earthworms in California forest ecosystems. A microcosm study of Argilophilus papillifer Eisen (Megascolecidae), a species indigenous to California, was conducted to ascertain its influence on chemical and physical properties of a California forest soil. Earthworms were incubated for 6 months in microcosms consisting of A-horizon soil and a surface layer of one

  4. A survey of Pb, Cu, Zn, Cd, Cr, As, and Se in earthworms and soil from diverse sites

    USGS Publications Warehouse

    Beyer, W.N.; Cromartie, E.J.

    1987-01-01

    Earthworms and soils were collected from 20 diverse sites in Maryland, Pennsylvania, and Virginia, and were analyzed for Pb, Cu, Zn, Cd, Cr, As, and Se. Correlation coefficients relating Iconcentrations of the elements in earthworms to concentrations in soil were low (-0.20earthworms. The maximum concentrations of Pb (2100 ppm), Zn (1600 ppm), Cd (23 ppm) and Se (7.6 ppm) detected in earthworms were in the range reported to be toxic to animals fed diets containing these elements; however, even in the absence of any environmental contamination, some species of earthworms may contain high concentrations of Pb, Zn, and Se. Earthworms of the genus Eisenoides, for example, were exceptional in their ability to concentrate Pb. When earthworms are used as indicators of environmental contamination, it is important to identify the species, to report the soil characteristics, and to collect similar earthworms from very similar but uncontaminated soil.

  5. Role of earthworms in nitrogen cycling during the cropping phase of shifting agriculture (Jhum) in north-east India

    Microsoft Academic Search

    Tunira Bhadauria; P. S. Ramakrishnan

    1996-01-01

    We investigated the role of earthworms in the N cycle in a shifting agriculture system under a 5- and a 15-year Jhum system fallow period intervening between two croppings on the same site. Earthworms participated in the N cycle through worm cast egestion, mucus production, and dead tissue decomposition. Soil N was initially depleted by volatilization during slash and burn

  6. Effect of industrial wastes of the oil palm on growth and reproduction phases of earthworm, Eisenia Andre

    Microsoft Academic Search

    J. A. Hernández; C. Contreras; R. Palma; A. Faria; S. Pietrosemoli

    Eleven mixtures of oil palms industrial wastes were prepared: peels (C) and fiber (F), with cattle manure (EB) in proportions of 0, 20, 40, 60, 80 and 100%. 100% EB was used as a control. The aim of the research was to evaluate the effect of these substrates on the growth and the reproduction of the earthworm. Ten earthworms were

  7. Potential of earthworms, ants, millipedes, and termites for dissemination of vesicular-arbuscular mycorrhizal fungi in soil

    Microsoft Academic Search

    K. M. Harinikumar; D. J. Bagyaraj

    1994-01-01

    We studied the effects of earthworms, termites, ants, and millipedes on the dissemination of vesciulararbuscular mycorrhizal (VAM) propagules. Earthworm (Lumbricus terrestris L.) casts collected from the garden were air-dried, stored, and examined for the presence of VAM fungi by inoculating the cast material onto onion plants grown in sterilized soil. VAM propagules survived for a period of 12 months. The

  8. The influence of the earthworm Lampito mauritii (Kinberg) on the activity of selected soil enzymes in cadmium-amended soil.

    PubMed

    Sivakumar, S; Prabha, D; Barathi, S; Nityanandi, D; Subbhuraam, C V; Lakshmipriya, T; Kamala-Kannan, Seralathan; Jang, S H; Yi, P I

    2015-03-01

    The effects of cadmium (CdCl2·7H2O) on cellulase, urease, amylase, invertase and phosphatase were assessed for a period of 45 days in the presence and absence of earthworms [Lampito mauritii (Kinberg)] in alfisol soil. The activities of all enzymes significantly increased with longer incubation times (45 days) under laboratory conditions in both control and Cd-amended soils (both with and without earthworm incubation). However, the activities of all enzymes decreased with increasing Cd concentrations under laboratory conditions, both in the presence and absence of earthworms. In the presence of earthworms, cellulase, urease, invertase and amylase activities increased. However, phosphatase activity was lower in most of the Cd-amended soils in the presence of earthworms compared to its activity levels in soils lacking earthworms. These results show that earthworms modulated the stress imposed by Cd by providing suitable substrates, which in turn acted as stimulants for extracellular enzyme secretion by microbes, and by removing Cd through its accumulation in the tissues of the earthworms. PMID:25647789

  9. Different behavioral patterns of the earthworms Octolasion tyrtaeum and Diplocardia spp. in tallgrass prairie soils: potential influences on plant growth

    Microsoft Academic Search

    Mac A. Callaham Jr; John M. Blair; Paul F. Hendrix

    2001-01-01

    This study addressed differences between Diplocardia spp. (a native North American earthworm) and Octolasion tyrtaeum (an introduced European species), with respect to behavior, influence on soil microbial biomass, and plant uptake of N in tallgrass prairie soils. We manipulated earthworms in PVC-encased soil cores (20 cm diameter) over a 45-day period under field conditions. Treatments included: (1) control with no

  10. The influence of earthworms (Lumbricidae) on the nitrogen dynamics in the soil litter system of a deciduous forest

    Microsoft Academic Search

    S. Scheu

    1987-01-01

    The influence of earthworms (Aporrectodea caliginosa (Savigny) and Lumbricus castaneus (Savigny)) on the rate of nitrogen net mineralization of the soil was studied in the laboratory and in the field. The additional mineralization of nitrogen cause by the burrowing activity of the substrat feeding earthworm A. caliginosa (NL)was directly correlated to the biomass of the lumbricids independently of their number.

  11. [Acute toxicological effects of excessive Cu and Zn-containing in pig manure on earthworm].

    PubMed

    Jia, Xiuying; Luo, Ancheng; Li, Ximei

    2005-08-01

    Cu and Zn are popularly used as additives in animal feed in China, which could result in their excessive accumulation in manure to a toxic level, and thus, possibly threaten the environment when the manure is applied to farmland. In this paper, the acute and sub-acute lethal effects of pig manure with excessive Cu and Zn on earthworm were studied, and the results indicated that the concentration of Cu and Zn in pig manure had a significantly positive correlation with the mortality of earthworm, while a significantly negative correlation with earthworm growth rate. The individuals of earthworm had different tolerance to excessive Cu and Zn, with the threshold values causing death being 250 mg x kg(-1) and 400 mg x kg(-1) for Cu and Zn, respectively. The LD50 was 646.68 mg x kg(-1) for Cu, and 947.38 mg x kg(-1) for Zn. A strong synergistic effect was observed under the combined pollution of 250 mg x kg(-1) for Cu and 500 mg x kg(-1) for Zn, whereas antagonistic effect happened when 750 mg x kg(-1) for Cu was supplied, suggesting that the joint toxic effects of Cu and Zn on earthworm were closely correlated to their concentrations in pig manure. PMID:16262072

  12. A dataset comprising four micro-computed tomography scans of freshly fixed and museum earthworm specimens

    PubMed Central

    2014-01-01

    Background Although molecular tools are increasingly employed to decipher invertebrate systematics, earthworm (Annelida: Clitellata: ‘Oligochaeta’) taxonomy is still largely based on conventional dissection, resulting in data that are mostly unsuitable for dissemination through online databases. In order to evaluate if micro-computed tomography (?CT) in combination with soft tissue staining techniques could be used to expand the existing set of tools available for studying internal and external structures of earthworms, ?CT scans of freshly fixed and museum specimens were gathered. Findings Scout images revealed full penetration of tissues by the staining agent. The attained isotropic voxel resolutions permit identification of internal and external structures conventionally used in earthworm taxonomy. The ?CT projection and reconstruction images have been deposited in the online data repository GigaDB and are publicly available for download. Conclusions The dataset presented here shows that earthworms constitute suitable candidates for ?CT scanning in combination with soft tissue staining. Not only are the data comparable to results derived from traditional dissection techniques, but due to their digital nature the data also permit computer-based interactive exploration of earthworm morphology and anatomy. The approach pursued here can be applied to freshly fixed as well as museum specimens, which is of particular importance when considering the use of rare or valuable material. Finally, a number of aspects related to the deposition of digital morphological data are briefly discussed. PMID:24839546

  13. Biomarker responses in earthworms (Eisenia fetida) to soils contaminated with di-n-butyl phthalates.

    PubMed

    Du, Li; Li, Guangde; Liu, Mingming; Li, Yanqiang; Yin, Suzhen; Zhao, Jie

    2015-03-01

    Di-n-butyl phthalates (DBP) are recognized as ubiquitous contaminants in soil and adversely impact the health of organisms. Changes in the activity of antioxidant enzymes and levels of glutathione-S-transferase (GST), glutathione (GSH), and malondialdehyde (MDA) were used as biomarkers to evaluate the impact of DBP on earthworms (Eisenia fetida) after exposure to DBP for 28 days. DBP was added to artificial soil in the amounts of 0, 5, 10, 50, and 100 mg kg(-1) of soil. Earthworm tissues exposed to each treatment were collected on the 7th, 14th, 21st, and 28th day of the treatment. We found that superoxide dismutase (SOD) and catalase (CAT) levels were significantly inhibited in the 100 mg kg(-1) treatment group on day 28. After 21 days of treatment, GST activity in 10-50 mg kg(-1) treatment groups was markedly stimulated compared to the control group. MDA content in treatment groups was higher than in the control group throughout the exposure time, suggesting that DBP may lead to lipid peroxidation (LPO) in cells. GSH content increased in the treatment group that received 50 mg kg(-1) DBP from 7 days of exposure to 28 days. These results suggest that DBP induces serious oxidative damage on earthworms and induce the formation of reactive oxygen species (ROS) in earthworms. However, DBP concentration in current agricultural soil in China will not constitute any threat to the earthworm or other animals in the soil. PMID:25328097

  14. Earthworm genomes, genes and proteins: the (re)discovery of Darwin's worms

    PubMed Central

    Stürzenbaum, S.R.; Andre, J.; Kille, P.; Morgan, A.J.

    2008-01-01

    Small incremental biological change, winnowed by natural selection over geological time scales to produce large consequences, was Darwin's singular insight that revolutionized the life sciences. His publications after 1859, including the ‘earthworm book’, were all written to amplify and support the evolutionary theory presented in the Origin. Darwin was unable to provide a physical basis for the inheritance of favoured traits because of the absence of genetic knowledge that much later led to the ‘modern synthesis’. Mistaken though he was in advocating systemic ‘gemmules’ as agents of inheritance, Darwin was perceptive in seeking to underpin his core vision with concrete factors that both determine the nature of a trait in one generation and convey it to subsequent generations. This brief review evaluates the molecular genetic literature on earthworms published during the last decade, and casts light on the specific aspects of earthworm evolutionary biology that more or less engaged Darwin: (i) biogeography, (ii) species diversity, (iii) local adaptations and (iv) sensitivity. We predict that the current understanding will deepen with the announcement of a draft earthworm genome in Darwin's bicentenary year, 2009. Subsequently, the earthworm may be elevated from the status of a soil sentinel to that elusive entity, an ecologically relevant genetic model organism. PMID:19129111

  15. Edaphic factors affecting the toxicity and accumulation of arsenate in the earthworm Lumbricus terrestris

    SciTech Connect

    Meharg, A.A.; Shore, R.F.; Broadgate, K. [Inst. of Terrestrial Ecology, Huntingdon (United Kingdom)

    1998-06-01

    The toxicity and accumulation of arsenate was determined in the earthworm Lumbricus terrestris in soil from different layers of a forest profile. Toxicity increased fourfold between 2 and 10 d. Edaphic factors (pH, soil organic matter, and depth in soil profile) also affected toxicity with a three fold decrease in the concentration that causes 50% mortality with increasing depth in soil. In a 4-d exposure study, there was no evidence of arsenic bioconcentration in earthworm tissue, although bioaccumulation was occurring. There was a considerable difference in tissue residues between living and dead earthworms, with dead worms having higher concentrations. This difference was dependent on both soil arsenate concentration and on soil type. Over a wide range of soil arsenate concentrations, earthworm arsenic residues are homeostatically maintained in living worms, but this homeostasis breaks down during death. Alternatively, equilibration with soil residues may occur via accumulation after death. In long-term accumulation studies in soils dosed with a sublethal arsenate concentration, bioconcentration of arsenate did not occur until day 12, after which earthworm concentrations rose steadily above the soil concentration, with residues in worms three fold higher than soil concentrations by the termination of the study. This bioconcentration only occurred in depurated worms over the time period of the study. Initially, depurated worms had lower arsenic concentrations than undepurated until tissue concentrations were equivalent to the soil concentration. Once tissue concentration was greater than soil concentration, depurated worms had higher arsenic residues than undepurated.

  16. The Mechanics and Energetics of Soil Bioturbation by Plant Roots and Earthworms - Plastic Deformation Considerations

    NASA Astrophysics Data System (ADS)

    Ruiz, Siul; Or, Dani; Schymanski, Stanislaus

    2014-05-01

    Soil structure plays a critical factor in the agricultural, hydrological and ecological functions of soils. These services are adversely impacted by soil compaction, a damage that could last for many years until functional structure is restored. An important class of soil structural restoration processes are related to biomechanical activity associated with burrowing of earthworms and root proliferation in impacted soil volumes. We study details of the mechanical processes and energetics associated with quantifying the rates and mechanical energy required for soil structural restoration. We first consider plastic cavity expansion to describe earthworm and plant root radial expansion under various conditions. We then use cone penetration models as analogues to wedging induced by root tip growth and worm locomotion. The associated mechanical stresses and strains determine the mechanical energy associated with bioturbation for different hydration conditions and root/earthworm geometries. Results illustrate a reduction in strain energy with increasing water content and trade-offs between pressure and energy investment for various root and earthworm geometries. The study provides the basic building blocks for estimating rates of soil structural alteration, the associated energetic requirements (soil carbon, plant assimilates) needed to sustain structure regeneration by earthworms and roots, and highlights potential mechanical cut-offs for such activities.

  17. Derived Avoidance Learning: Transformation of Avoidance Response Functions in Accordance with Same and Opposite Relational Frames

    ERIC Educational Resources Information Center

    Dymond, Simon; Roche, Bryan; Forsyth, John P.; Whelan, Robert; Rhoden, Julia

    2008-01-01

    Two experiments were designed to replicate and extend previous findings on the transformation of avoidance response functions in accordance with the relational frames of Same and Opposite. Participants were first exposed to non-arbitrary and arbitrary relational training and testing. Next, during avoidance conditioning, one stimulus from the…

  18. Signal Molecules Mediate the Impact of the Earthworm Aporrectodea caliginosa on Growth, Development and Defence of the Plant Arabidopsis thaliana

    PubMed Central

    Puga-Freitas, Ruben; Barot, Sébastien; Taconnat, Ludivine; Renou, Jean-Pierre; Blouin, Manuel

    2012-01-01

    Earthworms have generally a positive impact on plant growth, which is often attributed to a trophic mechanism: namely, earthworms increase the release of mineral nutrients from soil litter and organic matter. An alternative hypothesis has been proposed since the discovery of a signal molecule (Indole Acetic Acid) in earthworm faeces. In this study, we used methodologies developed in plant science to gain information on ecological mechanisms involved in plant-earthworm interaction, by looking at plant response to earthworm presence at a molecular level. First, we looked at plant overall response to earthworm faeces in an in vitro device where only signal molecules could have an effect on plant growth; we observed that earthworms were inducing positive or negative effects on different plant species. Then, using an Arabidopsis thaliana mutant with an impaired auxin transport, we demonstrated the potential of earthworms to stimulate root growth and to revert the dwarf mutant phenotype. Finally, we performed a comparative transcriptomic analysis of Arabidopsis thaliana in the presence and absence of earthworms; we found that genes modulated in the presence of earthworms are known to respond to biotic and abiotic stresses, or to the application of exogenous hormones. A comparison of our results with other studies found in databases revealed strong analogies with systemic resistance, induced by signal molecules emitted by Plant Growth Promoting Rhizobacteria and/or elicitors emitted by non-virulent pathogens. Signal molecules such as auxin and ethylene, which are considered as major in plant-microorganisms interactions, can also be of prior importance to explain plant-macroinvertebrates interactions. This could imply revisiting ecological theories which generally stress on the role of trophic relationships. PMID:23226498

  19. Human Hippocampus Arbitrates Approach-Avoidance Conflict

    PubMed Central

    Bach, Dominik R.; Guitart-Masip, Marc; Packard, Pau A.; Miró, Júlia; Falip, Mercč; Fuentemilla, Lluís; Dolan, Raymond J.

    2014-01-01

    Summary Animal models of human anxiety often invoke a conflict between approach and avoidance [1, 2]. In these, a key behavioral assay comprises passive avoidance of potential threat and inhibition, both thought to be controlled by ventral hippocampus [2–6]. Efforts to translate these approaches to clinical contexts [7, 8] are hampered by the fact that it is not known whether humans manifest analogous approach-avoidance dispositions and, if so, whether they share a homologous neurobiological substrate [9]. Here, we developed a paradigm to investigate the role of human hippocampus in arbitrating an approach-avoidance conflict under varying levels of potential threat. Across four experiments, subjects showed analogous behavior by adapting both passive avoidance behavior and behavioral inhibition to threat level. Using functional magnetic resonance imaging (fMRI), we observe that threat level engages the anterior hippocampus, the human homolog of rodent ventral hippocampus [10]. Testing patients with selective hippocampal lesions, we demonstrate a causal role for the hippocampus with patients showing reduced passive avoidance behavior and inhibition across all threat levels. Our data provide the first human assay for approach-avoidance conflict akin to that of animal anxiety models. The findings bridge rodent and human research on passive avoidance and behavioral inhibition and furnish a framework for addressing the neuronal underpinnings of human anxiety disorders, where our data indicate a major role for the hippocampus. PMID:24560572

  20. Simple biotoxicity tests for evaluation of carbonaceous soil additives: establishment and reproducibility of four test procedures.

    PubMed

    Busch, Daniela; Kammann, Claudia; Grünhage, Ludger; Müller, Christoph

    2012-01-01

    Biochar derived from pyrolysis has received much attention recently as a soil additive to sequester carbon and increase soil fertility. Hydrochar, a brown, coal-like substance produced via hydrothermal carbonization, has also been suggested as a beneficial soil additive. However, before soil application, both types of char need to be tested for potential toxic effects. The aim of this study was to develop simple, inexpensive, and easy-to-apply test procedures to identify negative effects of chars but not to provide false-negative results. The following tests, based partly on ISO norm biotoxicity test procedures, were chosen: (i) cress germination test for gaseous phytotoxic emissions; (ii) barley germination and growth test; (iii) salad germination test; and (iv) earthworm avoidance test for toxic substances. Test reproducibility was ensured by carrying out each test procedure three times with the same biochar. Several modifications were necessary to adapt the tests for biochars/hydrochars. The tested biochar did not induce negative effects in any of the tests. In contrast, the beet-root chip hydrochar showed negative effects in all tests. In an extension to the regular procedure, a regrowth of the harvested barley shoots without further nutrient additions yielded positive results for the hydrochar, which initially had negative effects. This implies that the harmful substance(s) must have been degraded or they were water soluble and leached. Tests with a biochar and hydrochar showed that the proposed modified quick-check test procedures provide a fast assessment of risks and effects of char application to soils within a short period of time (<2 wk). PMID:22751044

  1. Avoiding medical emergencies.

    PubMed

    Omar, Y

    2013-03-01

    Medical emergencies can occur at any time in any location. This article and associated presentation at the forthcoming British Dental Conference Exhibition provide key advice on avoiding medical emergencies in dental practice; including advice on risk assessing all patients, understanding the importance of a checklist, and using a National Early Warning Score (NEWS). PMID:23470404

  2. Avoiding the "M" Word.

    ERIC Educational Resources Information Center

    Klinger, Donna

    2001-01-01

    Provides an overview of roundtable discussions by top business officers about how higher education can capitalize on strategic alliances. Describes how, by working with one another and with corporate partners, colleges and universities can avoid closing their doors or merging with stronger institutions. (EV)

  3. Psychological Treatments to Avoid

    ERIC Educational Resources Information Center

    Thomason, Timothy C.

    2010-01-01

    Certain psychological treatments should be avoided, and a list of such treatments would provide valuable guidance for counselors, as well as potential clients. It is well established that some therapies are potentially dangerous, and some fringe therapies are highly unlikely to help clients beyond a placebo effect. This article provides an…

  4. Immune system participates in brain regeneration and restoration of reproduction in the earthworm Dendrobaena veneta.

    PubMed

    Molnar, Laszlo; Pollak, Edit; Skopek, Zuzanna; Gutt, Ewa; Kruk, Jerzy; Morgan, A John; Plytycz, Barbara

    2015-10-01

    Earthworm decerebration causes temporary inhibition of reproduction which is mediated by certain brain-derived neurohormones; thus, cocoon production is an apposite supravital marker of neurosecretory center functional recovery during brain regeneration. The core aim of the present study was to investigate aspects of the interactions of nervous and immune systems during brain regeneration in adult Dendrobaena veneta (Annelida; Oligochaeta). Surgical brain extirpation was combined, either with (i) maintenance of immune-competent coelomic cells (coelomocytes) achieved by surgery on prilocaine-anesthetized worms or (ii) prior extrusion of fluid-suspended coelomocytes by electrostimulation. Both brain renewal and cocoon output recovery were significantly faster in earthworms with relatively undisturbed coelomocyte counts compared with individuals where coelomocyte counts had been experimentally depleted. These observations provide empirical evidence that coelomocytes and/or coelomocyte-derived factors (e.g. riboflavin) participate in brain regeneration and, by implication, that there is close functional synergy between earthworm neural and immune systems. PMID:25863277

  5. Modelling the accumulation of hydrophobic organic chemicals in earthworms : Application of the equilibrium partitioning theory.

    PubMed

    Belfroid, A C; Scinen, W; van Gestel, K C; Hermens, J L; van Leeuwen, K J

    1995-07-01

    In this paper a method is developed which can be used to estimate the body burden of organic hydrophobic chemicals in earthworms. In contrast to the equilibrium partitioning theory, two routes of uptake are incorporated: uptake from interstitial water and dietary uptake. Although many uncertainties still remain, calculations show that for earthworms steady state body burdens are mainly determined by uptake from interstitial water. Under most circumstances, the contribution of dietary uptake is small, except for hydrophobic chemicals (log Kow > 5) in soils with a high organic matter (OM) content of ? 20 %. Under those conditions, estimates of the steady state body burden calculated with the equilibrium partitioning model, in which only uptake from interstitial water is taken into account, might result in a small underestimation of the real body burden of chemicals in earthworms. PMID:24234464

  6. Experiential Avoidance and Post-Traumatic Stress Disorder

    Microsoft Academic Search

    Laura E. Boeschen; Mary P. Koss; Aurelio Jose Figueredo; James A. Coan

    2001-01-01

    Does experiential avoidance predict PTSD severity among rape survivors? We tested a hypothesized model where causal attributions, cognitive schemas, and memory characteristics mediated the relationship between experiential avoidance and PTSD. Experiential avoidance was measured as a cognitive coping strategy; women scoring high on this measure did not try to integrate or make meaning of their rape experiences, but rather attempted

  7. Purification and characterization of a novel earthworm DNase.

    PubMed

    Zhu, Zhiqiang; Yang, Qi; Yu, Baofeng; Xie, Qiu; Wang, Jianhua; Wang, Xiuwei; Guan, Zhen; Li, Guannan; Han, Xu; Niu, Bo

    2015-01-01

    A new deoxyribonuclease (DNase), referred to as EWDNase, was isolated from earthworm tissues. The purification protocol included acetone precipitation, chromatography on CM-Sepharose, and gel electrophoresis. The overall purification was 73-fold with a recovery rate of 2.3% and a final specific activity of 2039 U/mg. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis suggested a molecular mass of 30 kD for EWDNase, with an isoelectric point of approximately 7.0. Maximum activity was detected at a pH of 5.6 and a temperature of 40°C. Addition of Mg(2+) and Ca(2+) ions promoted enzyme activity strongly, while Zn(2+) and ethylenediamine tetraacetic acid (EDTA) acted as inhibitors. Liquid chromatography-tandem mass spectroscopy (LC-MS/MS) analysis indicated that there was no known matching sequence. The properties of EWDNase were sufficiently different from previously reported enzymes to suggest that it is a new enzyme requiring further confirmation and characterization. PMID:24841139

  8. Metallothionein gene activation in the earthworm (Lumbricus rubellus).

    PubMed

    Höckner, M; Dallinger, R; Stürzenbaum, S R

    2015-05-01

    In order to cope with changing environmental conditions, organisms require highly responsive stress mechanisms. Heavy metal stress is handled by metallothioneins (MTs), the regulation of which is evolutionary conserved in insects and vertebrates and involves the binding of metal transcription factor 1 (MTF-1) to metal responsive elements (MREs) positioned in the promoter of MT genes. However, in most invertebrate phyla, the transcriptional activation of MTs is different and the exact mechanism is still unknown. Interestingly, although MREs are typically present also in invertebrate MT gene promoters, MTF-1 is notably absent. Here we use Lumbricus rubellus, the red earthworm, to study the elusive mechanism of wMT-2 activation in control and Cd-exposed conditions. EMSA and DNase I footprinting approaches were used to pinpoint functional binding sites within the wMT-2 promoter region, which revealed that the cAMP responsive element (CRE) is a promising candidate which may act as a transcriptional activator of invertebrate MTs. PMID:25797623

  9. Neurotropic and neuroprotective activities of the earthworm peptide Lumbricusin.

    PubMed

    Kim, Dae Hong; Lee, Ik Hwan; Nam, Seung Taek; Hong, Ji; Zhang, Peng; Hwang, Jae Sam; Seok, Heon; Choi, Hyemin; Lee, Dong Gun; Kim, Jae Il; Kim, Ho

    2014-06-01

    We recently isolated a polypeptide from the earthworm Lumbricus terrestris that is structurally similar to defensin, a well-known antibacterial peptide. An 11-mer antibacterial peptide (NH2-RNRRWCIDQQA), designated Lumbricusin, was synthesized based on the amino acid sequence of the isolated polypeptide. Since we previously reported that CopA3, a dung beetle peptide, enhanced neuronal cell proliferation, we here examined whether Lumbricusin exerted neurotropic and/or neuroprotective effects. Lumbricusin treatment induced a time-dependent increase (?51%) in the proliferation of human neuroblastoma SH-SY5Y cells. Lumbricusin also significantly inhibited the apoptosis and decreased viability induced by treatment with 6-hydroxy dopamine, a Parkinson's disease-mimicking agent. Immunoblot analyses revealed that Lumbricusin treatment increased ubiquitination of p27(Kip1) protein, a negative regulator of cell-cycle progression, in SH-SY5Y cells, and markedly promoted its degradation. Notably, adenoviral-mediated over-expression of p27(Kip1) significantly blocked the antiapoptotic effect of Lumbricusin in 6-hydroxy dopamine-treated SH-SY5Y cells. These results suggest that promotion of p27(Kip1) degradation may be the main mechanism underlying the neuroprotective and neurotropic effects of Lumbricusin. PMID:24796676

  10. Complete mitochondrial genome of an Amynthas earthworm, Amynthas aspergillus (Oligochaeta: Megascolecidae).

    PubMed

    Zhang, Liangliang; Jiang, Jibao; Dong, Yan; Qiu, Jiangping

    2014-10-20

    Abstract We have determined the mitochondrial genome of the first Amynthas earthworm, Amynthas aspergillus (Perrier, 1872), which is a natural medical resource in Chinese traditional medicine. Its mitogenome is 15,115?bp in length containing 37 genes with the same contents and order as other sequenced earthworms. All genes are encoded by the same strand, all 13 PCGs use ATG as start codon. The content of A + T is 63.04% for A. aspergillus (33.41% A, 29.63% T, 14.56% G and 22.41% C). The complete mitochondrial genomes of A. aspergillus would be useful for the reconstruction of Oligochaeta polygenetic relationships. PMID:25329289

  11. Gene expression of TLR homologues identified by genome-wide screening of the earthworm Dendrobaena veneta.

    PubMed

    Fjřsne, Trine F; Stenseth, Else-Berit; Myromslien, Frřydis; Rudi, Knut

    2015-02-01

    TLRs represent one of the most important components of innate immunity. Currently, these receptors have been extensively studied in vertebrates and insects, but our knowledge for annelids is very limited. Therefore, the aim of our study was to identify earthworm TLR homologs by genome-wide screening, and to determine the expression of candidate genes as a response to Gram-positive and Gram-negative bacteria. Using a combination of deep pyrosequencing and quantitative PCR we found six candidate genes, for which all were expressed in Dentrobaena veneta. Two of the candidates showed significant response to bacterial exposure. In conclusion, TLRs seem to have a role in earthworm immunology. PMID:24574024

  12. Visualization of enzyme activities inside earthworm biopores by in situ soil zymography

    NASA Astrophysics Data System (ADS)

    Thu Duyen Hoang, Thi; Razavi, Bahar. S.; Blagodatskaya, Evgenia; Kuzyakov, Yakov

    2015-04-01

    Earthworms can strongly activate microorganisms, increase microbial and enzyme activities and consequently the turnover of native soil organic matter. In extremely dynamic microhabitats and hotspots as biopores made by earthworms, the in situ enzyme activities are a footprint of complex biotic interactions. The effect of earthworms on the alteration of enzyme activities inside biopores and the difference between bio-pores and earthworm-free soil was visualized by in situ soil zymography (Spohn and Kuzyakov, 2014). For the first time, we prepared quantitative imaging of enzyme activities in biopores. Furthermore, we developed the zymography technique by direct application of a substrate saturated membrane to the soil to obtain better spatial resolution. Lumbricus terrestris L. was placed into transparent box (15×20×15cm). Simultaneously, maize seed was sown in the soil. Control soil box with maize and without earthworm was prepared in the same way. After two weeks when bio-pore systems were formed by earthworm, we visualized in situ enzyme activities of five hydrolytic enzymes (?-glucosidase, cellobiohydrolase, chitinase, xylanase, leucine aminopeptidase) and phosphatase. Followed by non-destructive zymography, biopore samples and control soil were destructively collected to assay enzyme kinetics by fluorogenically labeled substrates method. Zymography showed higher activity of ?-glucosidase, chitinase, xylanase and phosphatase in biopores comparing to bulk soil. These differences were further confirmed by fluorimetric microplate enzyme assay detected significant difference of Vmax in four above mentioned enzymes. Vmax of ?-glucosidase, chitinase, xylanase and phosphatase in biopores is 68%, 108%, 50% and 49% higher than that of control soil. However, no difference in cellobiohydrolase and leucine aminopeptidase kinetics between biopores and control soil were detected. This indicated little effect of earthworms on protein and cellulose transformation in soil. In conclusion, earthworms contribute to the decomposition of carbohydrates through promoting enzyme activities involved in the C-cycle except for leucine aminopeptidase and cellobiohydrolase. References Spohn M, Kuzyakov Y. (2014) Spatial and temporal dynamics of hotspots of enzyme activity in soil as affected by living and dead roots - a soil zymography analysis, Plant Soil 379: 67-77

  13. Involvement of the cholinergic system of CA1 on harmane-induced amnesia in the step-down passive avoidance test.

    PubMed

    Nasehi, Mohammad; Sharifi, Shahrbano; Zarrindast, Mohammad Reza

    2012-08-01

    ?-carboline alkaloids such as harmane (HA) are naturally present in the human food chain. They are derived from the plant Peganum harmala and have many cognitive effects. In the present study, effects of the nicotinic system of the dorsal hippocampus (CA1) on HA-induced amnesia and exploratory behaviors were examined. One-trial step-down and hole-board paradigms were used to assess memory retention and exploratory behaviors in adult male mice. Pre-training (15?mg/kg) but not pre-testing intraperitoneal (i.p.) administration of HA decreased memory formation but did not alter exploratory behaviors. Moreover, pre-testing administration of nicotine (0.5?µg/mouse, intra-CA1) decreased memory retrieval, but induced anxiogenic-like behaviors. On the other hand, pre-test intra-CA1 injection of ineffective doses of nicotine (0.1 and 0.25?µg/mouse) fully reversed HA-induced impairment of memory after pre-training injection of HA (15?mg/kg, i.p.) which did not alter exploratory behaviors. Furthermore, pre-testing administration of mecamylamine (0.5, 1 and 2?µg/mouse, intra-CA1) did not alter memory retrieval but fully reversed HA-induced impairment of memory after pre-training injection of HA (15?mg/kg, i.p.) which had no effect on exploratory behaviors. In conclusion, the present findings suggest the involvement of the nicotinic cholinergic system in the HA-induced impairment of memory formation. PMID:21965190

  14. Avoidance Learning TIAGO V. MAIA

    E-print Network

    in avoidance learning have been shown to generalize across species, and theories of avoidance learning for avoidance learning was based on Pavlov's stimulus-substitution theory. In Pavlov's experiments, a neutralAvoidance Learning TIAGO V. MAIA Department of Psychiatry, Columbia University and New York State

  15. Ruminative coping as avoidance

    Microsoft Academic Search

    Margaret Stroebe; Paul A. Boelen; Marcel van den Hout; Wolfgang Stroebe; Elske Salemink; Jan van den Bout

    2007-01-01

    The paper argues for a reconceptualization of ruminative coping with the death of a loved one as an avoidant rather than a\\u000a confrontational strategy. Ruminative coping has been characterized within the bereavement field as persistent, repetitive\\u000a and passive focus on negative emotions and symptoms. It has been theoretically described and empirically shown to be a maladaptive\\u000a process, being conceptually related

  16. Toxicity assessment of 45 pesticides to the epigeic earthworm Eisenia fetida.

    PubMed

    Wang, Yanhua; Wu, Shenggan; Chen, Liping; Wu, Changxing; Yu, Ruixian; Wang, Qiang; Zhao, Xueping

    2012-07-01

    This study was conducted to investigate comparative toxicity of 45 pesticides, including insecticides, acaricides, fungicides, and herbicides, toward the epigeic earthworm Eisenia fetida. Results from a 48-h filter paper contact test indicated that clothianidin, fenpyroximate, and pyridaben were supertoxic to E. fetida with LC(50) values ranging from 0.28 (0.24-0.35) to 0.72 (0.60-0.94) ?g cm(-2), followed by carbaryl, pyridaphenthion, azoxystrobin, cyproconazole, and picoxystrobin with LC(50) values ranging from 2.72 (2.22-0.3.19) to 8.48 (7.38-10.21) ?g cm(-2), while the other pesticides ranged from being relatively nontoxic to very toxic to the worms. When tested in artificial soil for 14 d, clothianidin and picoxystrobin showed the highest intrinsic toxicity against E. fetida, and their LC(50) values were 6.06 (5.60-6.77) and 7.22 (5.29-8.68) mg kg(-1), respectively, followed by fenpyroximate with an LC(50) of 75.52 (68.21-86.57) mgkg(-1). However, the herbicides fluoroglycofen, paraquat, and pyraflufen-ethyl exhibited the lowest toxicities with LC(50) values>1000 mg kg(-1). In contrast, the other pesticides exhibited relatively low toxicities with LC(50) values ranging from 133.5 (124.5-150.5) to 895.2 (754.2-1198.0) mg kg(-1). The data presented in this paper provided useful information for evaluating the potential risk of these chemicals to soil invertebrates. PMID:22459421

  17. Passive samplers provide a better prediction of PAH bioaccumulation in earthworms and plant roots than exhaustive, mild solvent, and cyclodextrin extractions.

    PubMed

    Gomez-Eyles, Jose L; Jonker, Michiel T O; Hodson, Mark E; Collins, Chris D

    2012-01-17

    A number of extraction methods have been developed to assess polycyclic aromatic hydrocarbon (PAH) bioavailability in soils. As these methods are rarely tested in a comparative manner, against different test organisms, and using field-contaminated soils, it is unclear which method gives the most accurate measure of the actual soil ecosystem exposure. In this study, PAH bioavailability was assessed in ten field-contaminated soils by using exhaustive acetone/hexane extractions, mild solvent (butanol) extractions, cyclodextrin extractions, and two passive sampling methods; solid phase micro extraction (SPME) and polyoxymethylene solid phase extraction (POM-SPE). Results were compared to actual PAH bioaccumulation in earthworms (Eisenia fetida) and rye grass (Lolium multiflorum) roots. Exhaustive, mild solvent and cyclodextrin extractions consistently overpredicted biotic concentrations by a factor of 10-10?000 and therefore seem inappropriate for predicting PAH bioaccumulation in field contaminated soils. In contrast, passive samplers generally predicted PAH concentrations in earthworms within a factor of 10, although correlations between predicted and measured concentrations were considerably scattered. The same applied to the plant data, where passive samplers also tended to underpredict root concentrations. These results indicate the potential of passive samplers to predict PAH bioaccumulation, yet call for comparative studies between passive samplers and further research on plant bioavailability. PMID:22191550

  18. Rapid bioassessment methods for assessing the toxicity of terrestrial waste sites at the Savannah River Site using the earthworm, Eisenia foetida

    SciTech Connect

    Specht, W.L. [Westinghouse Savannah River Co., Aiken, SC (United States). Savannah River Technology Center; Sydow, S.N. [Clemson Univ., SC (United States)

    1995-08-01

    Studies were conducted to assess the feasibility of using the earthworm, Eisenia foetida, to evaluate the toxicity of contaminated soils at the Savannah River Site. Survival was assessed in several uncontaminated soils, including sandy loams and clayey loams, as well as in soils contaminated with coal fines, ash, diesel fuel, and heavy metals. In addition, behavior responses, changes in biomass, and bioaccumulation of heavy metals were assessed as sublethal indicators of toxicity. The results indicate excellent survival of Eisenia foetida in uncontaminated sandy and clayey soils. No amendment of these uncontaminated soils or addition of food was necessary to sustain the worms for the 14-day test period. In contaminated soils, no significant mortality was observed, except in soils which have very low pH (< 3). However, sublethal responses were observed in earthworms exposed to several of the contaminated soils. These responses included worms clumping on the surface of the soil, worms clumping between the sides of the test container and the soil, increased burrowing times, reductions in biomass, and elevated concentrations of heavy metals in worm tissue.

  19. Comparison of the chemical alteration trajectory of Liriodendron tulipifera L. leaf litter among forests with different earthworm abundance

    NASA Astrophysics Data System (ADS)

    Filley, Timothy R.; McCormick, Melissa K.; Crow, Susan E.; Szlavecz, Katalin; Whigham, Dennis F.; Johnston, Cliff T.; van den Heuvel, Ronald N.

    2008-03-01

    To investigate the control of earthworm populations on leaf litter biopolymer decay dynamics, we analyzed the residues of Liriodendron tulipifera L. (tulip poplar) leaves after six months of decay, comparing open surface litter and litter bag experiments among forests with different native and invasive earthworm abundances. Six plots were established in successional tulip poplar forests where sites varied in earthworm density and biomass, roughly 4-10 fold, of nonnative lumbricid species. Analysis of residues by diffuse reflectance Fourier transform infrared spectroscopy and alkaline CuO extraction indicated that open decay in sites with abundant earthworms resulted in residues depleted in cuticular aliphatic and polysaccharide components and enriched in ether-linked lignin relative to open decay in low earthworm abundance plots. Decay within earthworm-excluding litter bags resulted in an increase in aliphatic components relative to initial amendment and similar chemical trajectory to low earthworm open decay experiments. All litter exhibited a decline in cinnamyl-based lignin and an increase in nitrogen content. The influence of earthworm density on the chemical trajectory of litter decay was primarily a manifestation of the physical separation and concentration of lignin-rich and cutin-poor petioles with additional changes promoted by either microorganisms and/or mesofauna resulting in nitrogen addition and polysaccharide loss. These results illustrate how projected increases in invasive earthworm activity in northern North American forests could alter the chemical composition of organic matter in litter residues and potentially organic matter reaching the soil which may result in shifts in the aromatic and aliphatic composition of soils in different systems.

  20. Avoidance of hydrolyzed casein by mice

    PubMed Central

    Field, Kristin L.; Kimball, Bruce A.; Mennella, Julie A.; Beauchamp, Gary K.; Bachmanov, Alexander A.

    2008-01-01

    When casein, a milk protein, is hydrolyzed, it renders human foods that contain it (e.g., hypoallergenic infant formula, cheeses) distasteful to many people. This rejection of hydrolyzed casein (HC)-containing foods has recently been found to also occur in a non-human species (deer, Odocoileus spp.). Identifying other animals that avoid HC would facilitate understanding how and why HC-containing food is often rejected. This study determined whether HC-containing food is avoided by Mus musculus and whether consumption patterns were sensitive to testing conditions, specifically food form (powder, pellet or dough) and food access (ad libitum or 1.5 h/day following 6 h of food deprivation). Diets were offered in two-choice tests that paired an HC-containing food with an intact casein-containing alternative at seven protein concentrations (0%–50% w/w). Five experimental groups were tested under different combinations of food form and food access. Three groups (ad lib/powder, ad lib/pellet, and 1.5 h/pellet) avoided the HC diet starting at the 30% protein level. At the 40% and 50% protein levels, all groups showed strong avoidance of HC. Although testing conditions influenced total caloric intake and body weight gain, avoidance of HC at the highest concentrations was robust to the manipulations in experimental conditions. Our study suggests that mice may be a useful model for understanding the mechanisms of HC rejection. PMID:17900635

  1. Involvement of dopamine D1/D2 receptors on harmane-induced amnesia in the step-down passive avoidance test.

    PubMed

    Nasehi, Mohammad; Piri, Morteza; Nouri, Maryam; Farzin, Davood; Nayer-Nouri, Touraj; Zarrindast, Mohammad Reza

    2010-05-25

    Ingestion of harmane and other alkaloids derived from plant Peganum harmala has been shown to elicit profound behavioural and toxic effects in humans, including hallucinations, excitation, feelings of elation, and euphoria. These alkaloids in the high doses can cause a toxic syndrome characterized by tremors and convulsions. Harmane has also been shown to act on a variety of receptor systems in the mammalian brain, including those for serotonin, dopamine and benzodiazepines. In animals, it has been reported to affect short and long term memory. In the present study, effects of dopamine D1 and D2 receptor antagonists on the harmane (HA)-induced amnesia and exploratory behaviors were examined in mice. One-trial step-down and hole-board paradigms were used for the assessment of memory retention and exploratory behaviors in adult male NMRI mice respectively. Intraperitoneal (i.p.) administration of HA (5 and 10 mg/kg) immediately after training decreased memory consolidation, while had no effect on anxiety-like behavior. Memory retrieval was not altered by 15- or 30 min pre-testing administration of the D1 (SCH23390, 0.025, 0.05 and 0.1 mg/kg) or D2 (sulpiride 12.5, 25 and 50 mg/kg) receptor antagonists, respectively. In contrast, SCH23390 (0.05 and 0.1 mg/kg) or sulpiride (25 and 50 mg/kg) pre-test administration fully reversed HA-induced impairment of memory consolidation. Finally, neither D1 nor D2 receptor blockade affected exploratory behaviors in the hole-board paradigm. Altogether, these findings strongly suggest an involvement of D1 and D2 receptors modulation in the HA-induced impairment of memory consolidation. PMID:20188725

  2. Analysis of chemicals from earthworms and fish that elicit prey attack by ingestively naive garter snakes (Thamnophis).

    PubMed

    Schell, F M; Burghardt, G M; Johnston, A; Coholich, C

    1990-01-01

    Materials previously shown to elicit increased tongue-flicking and prey attack in garter snakes (Thamnophis sirtalis) were isolated from both earthworms (Lumbricus terrestris) and fish (Pimephales promelas). Both high- and low-molecular-weight components from earthworms and fish stimulated attacks and increased tongue-flicking in previously unfed neonate garter snakes relative to distilled water controls. Earthworm collagen was also effective, but even concentrated fractions were less effective than raw extract. Conflicting reports on the effectiveness of collagen suggest that the salient chemical(s) is a smaller molecule tightly bound to collagen and resisting standard purification methods. PMID:24264896

  3. Effect of earthworm loads on organic matter and nutrient removal efficiencies in synthetic domestic wastewater, and on bacterial community structure and diversity in vermifiltration.

    PubMed

    Wang, L M; Luo, X Z; Zhang, Y M; Lian, J J; Gao, Y X; Zheng, Z

    2013-01-01

    In this paper, we studied the effect of earthworm loads on the removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total nitrogen, and total phosphorus from synthetic domestic sewage and on the bacterial community structure and diversity of substrates in earthworm packing beds. The different vermifiltrations (VFs), including the control, are successful in removing both organic matter (OM) and nutrients. The removal rate of NH3-N at 12.5 g of earthworm/L of soil VF is higher compared with that at 0 and 4.5 earthworm load VFs. The highest Shannon index, in the earthworm packing bed, occurred at 16.5 earthworm load VF. Furthermore, the COD removal rate is significantly correlated with the Shannon index, which reveals that OM removal for synthetic domestic sewage treatment at VF might be more dependent on bacterial diversity at the earthworm packing bed. The band distributions and diversities of the bacterial community for samples from different earthworm loads in VFs suggest that the bacterial community structure was only affected within the earthworm packing bed when the earthworm load reached a certain level. The present study adds to the current understanding of OM and nutrient degradation processes in VF domestic wastewater treatment. PMID:23823538

  4. Avoiding Death by Vacuum

    E-print Network

    A. Barroso; P. M. Ferreira; I. Ivanov; R. Santos; Joao P. Silva

    2013-05-08

    The two-Higgs doublet model (2HDM) can have two electroweak breaking, CP-conserving, minima. The possibility arises that the minimum which corresponds to the known elementary particle spectrum is metastable, a possibility we call the "panic vacuum". We present analytical bounds on the parameters of the softly broken Peccei-Quinn 2HDM which are necessary and sufficient conditions to avoid this possibility. We also show that, for this particular model, the current LHC data already tell us that we are necessarily in the global minimum of the theory, regardless of any cosmological considerations about the lifetime of the false vacua.

  5. Vermiremediation of dyeing sludge from textile mill with the help of exotic earthworm Eisenia fetida Savigny.

    PubMed

    Bhat, Sartaj Ahmad; Singh, Jaswinder; Vig, Adarsh Pal

    2013-09-01

    The aim of present study was for the vermiremediation of dyeing sludge from textile mill into nutrient-rich vermicompost using earthworm Eisenia fetida. The dyeing sludge was mixed with cattle dung in different ratios, i.e., 0:100 (D0), 25:75 (D25), 50:50 (D50), 75:25 (D75), and 100:0 (D100) with earthworms, and 0:100 (S0), 25:75 (S25), 50:50 (S50), 75:25 (S75), and 100:0 (S100) without earthworms. Minimum mortality and maximum population build-up were observed in a 25:75 mixture. Nitrogen, phosphorus, sodium, and pH increased from the initial to the final products with earthworms, while electrical conductivity, C/N ratio, organic carbon, and potassium declined in all the feed mixtures. Vermicomposting with E. fetida was better for composting to change this sludge into nutrient-rich manure. PMID:23508537

  6. APPLICATION OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF A LEAD-CONTAMINATED SOIL

    EPA Science Inventory

    Earthworm acute toxicity, plant seed germination/root elongation (SG/RE) and plant genotoxicity bioassays were employed to evaluate the remediation of a lead-contaminated soil. The remediation involved removal of heavy metals by a soil washing/soil leaching treatment process. A p...

  7. Invasion of a deciduous forest by earthworms: Changes in soil chemistry, microflora, microarthropods and vegetation

    Microsoft Academic Search

    Nico Eisenhauer; Stephan Partsch; Dennis Parkinson; Stefan Scheu

    2007-01-01

    Ecosystems of northern North America existed without earthworm fauna until European settlers arrived and introduced European species. The current extent of invasion by some of these species, Lumbricus terrestris L., Octolasion tyrtaeum Savigny and Dendrobaena octaedra Savigny, into an aspen forest in the Canadian Rocky Mountains and the effects of the invasion on soil chemistry, microflora, soil microarthropods and vegetation

  8. Peat amendment and production of different crop plants affect earthworm populations in field soil

    Microsoft Academic Search

    Sanna Kukkonen; Ansa Palojärvi; Mauri Räkköläinen; Mauritz Vestberg

    2004-01-01

    A field experiment was conducted to study the effects of peat amendment and crop production system on earthworms. The experiment was established on a field previously cultivated with oats and with silt as the main soil type. Perennial crops strawberry, timothy and caraway, and annual crops rye, turnip rape, buckwheat, onion and fiddleneck were cultivated with conventional methods. All the

  9. Earthworms facilitate carbon sequestration through unequal amplification of carbon stabilization compared with mineralization

    EPA Science Inventory

    A recent review concluded that earthworm presence increases CO2 emissions by 33% but does not affect soil organic carbon stocks. However, the findings are controversial and raise new questions. Here we hypothesize that neither an increase in CO2 emission nor in stabilized carbon...

  10. Toxicological effects of multi-walled carbon nanotubes adsorbed with nonylphenol on earthworm Eisenia fetida.

    PubMed

    Hu, Changwei; Cai, Yun; Wang, Weili; Cui, Yibin; Li, Mei

    2013-10-01

    The high surface area of multi-walled carbon nanotubes (MWCNTs) tends to adsorb a large variety of toxic chemicals, which may enhance the toxicity of both MWCNTs and chemicals to organisms. In order to evaluate the combined toxicity of nonylphenol (NP) and MWCNTs to the earthworm Eisenia fetida in soil, artificial soil systems containing distilled water, 0.1 g kg(-1) MWCNTs, 1 g kg(-1) MWCNTs, 1 g kg(-1) MWCNTs absorbed 5 mg kg(-1) NP, and 10 mg kg(-1) NP alone were prepared and exposed to earthworms for 7 days. Antioxidative responses, and activities of cellulase, Na(+), K(+)-ATPase and acetylcholinesterase (TChE) as well as DNA damage were chosen as toxicological endpoints. The results showed that 1 g kg(-1) MWCNTs adsorbed 5 mg kg(-1) NP from the soil which caused much more adverse effects on the earthworms than each chemical alone, evident from the responses of cellulase, Na(+), K(+)-ATPase and comet assay. This study indicated that MWCNTs facilitated the bioavailability of NP to the earthworm and increased the harmful effects of NP. PMID:24104387

  11. Bioconversion of filter mud using vermicomposting employing two exotic and one local earthworm species

    Microsoft Academic Search

    Meena Khwairakpam; Renu Bhargava

    2009-01-01

    Three different earthworm species Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus in individual (Monocultures) and combinations (Polycultures) were utilized to compare the suitability of worm species for vermicomposting of filter mud as well as the quality of the end product. The filter mud blended with saw dust can be directly converted into good quality fertilizer (vermicompost). Eight different reactors including

  12. Enhanced Microbial Removal of Pyrene in Soils in the Presence of Earthworms

    Microsoft Academic Search

    Hongwen Sun; Jieming Li; Cuiping Wang; Lei Wang; Yingying Wang

    2011-01-01

    Microbial degradation of pyrene was studied in soils in the presence and absence of earthworms (Eisenia foetida) to demonstrate an integrated innovative strategy for bioremediation of sites lightly polluted by polycyclic aromatic hydrocarbons. Desorption of pyrene and soil microbial respiration were measured to elucidate the mechanism of enhanced microbial degradation. The results showed that both soil properties and contact time

  13. Effects of earthworm casts and compost on soil microbial activity and plant nutrient availability

    Microsoft Academic Search

    Hala I Chaoui; Larry M Zibilske; Tsutomu Ohno

    2003-01-01

    Vermicomposting differs from conventional composting because the organic material is processed by the digestive systems of worms. The egested casts can be used to improve the fertility and physical characteristics of soil and potting media. In this study, the effects of earthworm casts (EW), conventional compost (CP) and NPK inorganic fertilizer (FT) amendments on N mineralization rates, microbial respiration, and

  14. Glycogen-lead relationship in the earthworm Dendrobaena rubida from a heavy metal site

    Microsoft Academic Search

    K. Sylvia Richards; M. P. Ireland

    1978-01-01

    Control individuals contained no lead in the chloragocytes but high a-glycogen rosette reserves. Starvation of contaminated earthworms for 4d caused a lead loss and the chloragocytes possessed fewer debris vesicles than those of unstarved worms, suggesting that the debris vesicles may be the route for at least some of the lead loss. No glycogen deposits were observed in the chloragocytes

  15. The cytotoxic and genotoxic effects of metalaxy-M on earthworms (Eisenia fetida).

    PubMed

    Liu, Tong; Zhu, Lusheng; Han, Yingnan; Wang, Jinhua; Wang, Jun; Zhao, Yan

    2014-10-01

    As the main optical isomer of metalaxyl, metalaxyl-M has been widely used worldwide in recent years because of its notable effect on the prevention and control of crop diseases. Together with the toxicity and degradation of metalaxyl-M, the chemical has attracted the attention of researchers. The present study examined the toxic effects of metalaxyl-M on earthworms at 0?mg?kg(-1) , 0.1?mg?kg(-1) , 1?mg?kg(-1) , and 3?mg?kg(-1) on days 7, 14, 21 and 28 after exposure. The results showed that metalaxyl-M could cause an obvious increase in the production of reactive oxygen species (ROS) when the concentration was higher than 0.1?mg?kg(-1) , which led to lipid peroxidation in earthworms. Metalaxyl-M can induce DNA damage in earthworms, and the level of DNA damage markedly increased with increasing the concentration of metalaxyl-M. Metalaxyl-M also has a serious influence on the activities of antioxidant enzymes, which results in irreversible oxidative damage in cells. The changes of these indicators all indicated that metalaxyl-M may cause cytotoxic and genotoxic effects on earthworms. PMID:25043480

  16. Integrated assessment of oxidative stress and DNA damage in earthworms (Eisenia fetida) exposed to azoxystrobin.

    PubMed

    Han, Yingnan; Zhu, Lusheng; Wang, Jinhua; Wang, Jun; Xie, Hui; Zhang, Shumin

    2014-09-01

    Azoxystrobin has been widely used in recent years. The present study investigated the oxidative stress and DNA damage effects of azoxystrobin on earthworms (Eisenia fetida). Earthworms were exposed to different azoxystrobin concentrations in an artificial soil (0, 0.1, 1, and 10mg/kg) and sampled on days 7, 14, 21, and 28. Superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (POD), glutathione-S-transferase (GST), reactive oxygen species (ROS), and malondialdehyde (MDA) content were measured by an ultraviolet spectrophotometer to determine the antioxidant responses and lipid peroxidation. Single cell gel electrophoresis (SCGE) was used to detect DNA damage in the coelomocytes. Compared with these in the controls, earthworms exposed to azoxystrobin had excess ROS accumulation and greater SOD, POD, and GST activity while the opposite trend occurred for CAT activity. MDA content increased after 14-day exposure, and DNA damage was enhanced with an increase in the concentration of azoxystrobin. In conclusion, azoxystrobin caused oxidative stress leading to lipid peroxidation and DNA damage in earthworms. PMID:25011117

  17. Toxicity of zinc oxide nanoparticles in the earthworm, Eisenia fetida and subcellular fractionation of Zn

    Microsoft Academic Search

    Lian-Zhen Li; Dong-Mei Zhou; Willie J. G. M. Peijnenburg; Cornelis A. M. van Gestel; Sheng-Yang Jin; Yu-Jun Wang; Peng Wang

    2011-01-01

    The extensive use of nanoparticles (NPs) in a variety of applications has raised great concerns about their environmental fate and biological effects. This study examined the impact of dissolved organic matter (DOM) and salts on ZnO NP dispersion\\/solubility and toxicity to the earthworm Eisenia fetida. To be able to better evaluate the toxicity of NPs, exposure in agar and on

  18. Earthworms as useful bioindicators of agroecosystem sustainability in orchards and vineyards with different inputs

    Microsoft Academic Search

    M. G Paoletti; D Sommaggio; M. R Favretto; G Petruzzelli; B Pezzarossa; M Barbafieri

    1998-01-01

    Earthworm communities were studied in 72 different agroecosystems including vineyards and three types of orchards: apple, peach and kiwi. Orchards had different agricultural inputs, in particular copper (namely, copper sulphate applied as fungicide), and soil cultivation. Heavy metals were analyzed together with other soil parameters (nutrients, bacteria and fungi). No differences were detected regarding microorganisms in orchards subjected to different

  19. Earthworm excreta attract soil springtails: laboratory experiments on Heteromurus Nitidus (Collembola: Entomobryidae)

    E-print Network

    Paris-Sud XI, Université de

    (Collembola: Entomobryidae) Sandrine Salmon , Jean-François Ponge Museum National d'Histoire Naturelle casts. The same experiment involving direct contact with mucus and methyl blue showed that Collembola sucked on mucus/urine, indicating that the interaction of Collembola and earthworms was at least partly

  20. The impact of organophosphate pesticides in orchards on earthworms in the Western Cape, South Africa.

    PubMed

    Reinecke, S A; Reinecke, A J

    2007-02-01

    Earthworm population density was measured in and adjacent to an orchard in an agricultural area in the Western Cape, South Africa. Worm densities were very low in orchards (22/m(2)) compared to adjacent uncultivated fields (152/m(2)) at a distance from the orchards. The possible effect of organophosphate pesticides on the earthworms was investigated. Background soil concentrations of chlorpyrifos prior to the start of the spraying season were low (0.2-2.7 microg/kg) but persistent for up to 6 months after the last spraying event, and the pesticide was, as a result of rainfall, transported to nontarget areas by runoff. Background concentrations of azinphos methyl were higher than those of chlorpyrifos (1.6-9.8 microg/kg) but not detectable 2 weeks after a spraying event. Azinphos methyl was mostly transported by wind (spray drift) to adjacent areas. A microcosm study indicated effects of chlorpyrifos on earthworms as determined by measuring biomass change and Cholinesterase inhibition. It is concluded that earthworms were affected detrimentally by the pesticides due to chronic (chlorpyrifos) and intermittent (azinphos methyl) exposure. PMID:16318873

  1. Charles Darwin, earthworms and the natural sciences: various lessons from past to future

    Microsoft Academic Search

    Christian Feller; George G Brown; Eric Blanchart; Pierre Deleporte; Sergey S Chernyanskii

    2003-01-01

    In 1881, Darwin (1809–1882) published his last scientific book entitled “The formation of vegetable mould through the action of worms with observations on their habits”, the result of several decades of detailed observations and measurements on earthworms and the natural sciences. The work was considered a “best-seller” at the time, with 3500 copies sold immediately and 8500 in less than

  2. TERATOGENIC EFFECTS OF THE FUNGICIDE BENOMYL ON POSTERIOR SEGMENTAL REGENERATION IN THE EARTHWORM, 'EISENIA FETIDA'

    EPA Science Inventory

    Earthworms, Eisenia fetida, were treated by surface exposure to the fungicide benomyl at various stages of posterior segmental regeneration. Teratogenic effects of benomyl were observed when worms were treated 7-11 days after amputation (i.e. during the normal period of segmental...

  3. Impact of roots, mycorrhizas and earthworms on soil physical properties as assessed by shrinkage analysis

    Microsoft Academic Search

    R. Milleret; R.-C. Le Bayon; F. Lamy; J.-M. Gobat; P. Boivin

    2009-01-01

    sum mar y Soil biota such as earthworms, arbuscular mycorrhizal fungi (AMF) and plant roots are known to play a major role in engineering the belowground part of the terrestrial ecosystems, thus strongly influencing the water budget and quality on earth. However, the effect of soil organisms and their interactions on the numerous soil physical properties to be considered are

  4. Detrimental Influence of Invasive Earthworms on North American Cold-Temperate Forest Soils

    ERIC Educational Resources Information Center

    Enerson, Isabel

    2012-01-01

    The topic of invasive earthworms is a timely concern that goes against many preconceived notions regarding the positive benefits of all worms. In the cold-temperate forests of North America invasive worms are threatening forest ecosystems, due to the changes they create in the soil, including decreases in C:N ratios and leaf litter, disruption of…

  5. Soil Biology & Biochemistry 38 (2006) 16081614 Endogeic earthworms differentially influence bacterial communities

    E-print Network

    Rilli, Matthias C.

    2006-01-01

    C. Rilliga , Johan Sixb a Division of Biological Sciences, Microbial Ecology Program, The University-facilitated aggregate formation, how and where within the soil matrix earthworm-facilitated influences on soil microbial, the extent to which microbial communities associated with different soil microhabitats are affected is

  6. Population dynamics of the earthworm Aporrectodea trapezoides (Annelida: Lumbricidae) in a Western Australian pasture soil

    Microsoft Academic Search

    T. A. McCredie; C. A. Parker; I. Abbott

    1992-01-01

    The changes in size and age-composition of an earthworm population were studied in a Western Australian pasture developed since 1912. The population size in the surface 10 cm was estimated by handsorting during the cool wet season (19 weeks from May to September). Two species, both exotic, were found, Aporrectodea tranpezoides (Lumbricidae) and Microscolex dubius (Acanthodrilidae). Of the 615 individual

  7. Comparative Assessment of the Aerobic and Anaerobic Microfloras of Earthworm Guts and Forest Soils

    PubMed Central

    Karsten, G. R.; Drake, H. L.

    1995-01-01

    Aerobic and anaerobic microbial potentials of guts from earthworms (Lumbricus rubellus Hoffmeister and Octolasium lacteum (Oerl.)) collected from a beech forest were evaluated. On the basis of enumeration studies, microbes capable of growth under both aerobic and anaerobic conditions were more numerous in the earthworm intestine than in the beech forest soil from which the worms were obtained. The intestine of worms displayed nearly equivalent aerobic and anaerobic microbial growth potentials; in comparison, soils displayed greater aerobic than anaerobic microbial growth potentials. Hence, the ratio of microbes capable of growth under obligately anaerobic conditions to those capable of growth under aerobic conditions was higher with the worm intestine than with the soil. Process level studies corroborated these population differentials: (i) under anaerobic conditions, worm gut homogenates consumed glucose, cellobiose, or ferulate more readily than did soil homogenates; and (ii) under aerobic conditions, worm gut homogenates consumed cellobiose or oxygen more readily than did soil homogenates. Collectively, these results reinforce the general concept that the earthworm gut is not microbiologically equivalent to soil and also suggest that the earthworm gut might constitute a microhabitat enriched in microbes capable of anaerobic growth and activity. PMID:16534954

  8. Earthworm populations in septic system filter fields and potential effects on wastewater renovation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wastewater renovation in septic-system filter fields can be affected by preferential flow through soil macropores. Earthworm burrows may contribute to this concern by penetrating the infiltrative surface of soil-treatment trenches. Additionally, the moist, nutrient-rich environment surrounding tre...

  9. Influence of Citric Acid Amendments on the Availability of Weathered PCBs to Plant and Earthworm Species

    Microsoft Academic Search

    Jason C. White; Zakia D. Parrish; Mehmet Isleyen; Martin P. N. Gent; William Iannucci-Berger; Brian D. Eitzer; Jason W. Kelsey; Maryjane Incorvia Mattina

    2006-01-01

    A series of small and large pot trials were conducted to assess the phytoextraction potential of several plant species for weathered polychlorinated biphenyls (PCBs) in soil (105 ? g\\/g Arochlor 1268). In addition, the effect of citric acid on PCB bioavailability to both plants and earthworms was assessed. Under small pot conditions (one plant, 400 g soil), three cucurbits (Cucurbita

  10. Soil surface macrofaunal communities associated with earthworm casts in grasslands of the Eastern Plains of Colombia

    Microsoft Academic Search

    Thibaud Decaëns; Lucero Mariani; Patrick Lavelle

    1999-01-01

    Earthworms are known to modify life conditions for other soil organisms through their drilospheric activities. The effects of a large anecic species, Martiodrilus carimaguensis Jiménez and Moreno, on soil macrofaunal communities were investigated in a natural and a man-made grassland of the Eastern Plains of Colombia. Invertebrates were sampled by a standard hand sorting method at different spatial scales: (i)

  11. Inferred threat and safety: symbolic generalization of human avoidance learning.

    PubMed

    Dymond, Simon; Schlund, Michael W; Roche, Bryan; Whelan, Robert; Richards, Jennifer; Davies, Cara

    2011-10-01

    Symbolic generalization of avoidance may underlie the aetiology and maintenance of anxiety disorders. The aim of the present study was to demonstrate inferred threat-avoidance and safety (non-avoidance) behaviours that occur in the presence of stimuli indirectly related to learned threat and safety cues. A laboratory experiment was conducted involving two symbolic stimulus equivalence relations consisting of three physically dissimilar stimuli (avoidance cues: AV1-AV2-AV3 and neutral cues: N1-N2-N3). During avoidance learning involving aversive images and sounds, a key-press avoidance response was trained for one member of one of the relations (AV2) and non-avoidance for another (N2). Inferred threat and safety behaviour and ratings of the likelihood of aversive events were tested with presentations of all remaining stimuli. Findings showed a significantly high percentage of avoidance to both the learned and inferred threat cues and less avoidance to both the learned and inferred safety cues. Ratings in the absence of avoidance were high during training and testing to threat cues and low to safety cues and were generally lower in the presence of avoidance. Implications for associative and behavioural accounts of avoidance, and modern therapies for anxiety disorders are discussed. PMID:21767825

  12. Role of Native and Exotic Earthworms in Plant Biopolymer Dynamics in Forest Soil

    NASA Astrophysics Data System (ADS)

    Filley, Timothy

    2010-05-01

    Many forests within northern North America are experiencing the introduction of earthworms for the first time, presumably since before the last major glaciation. Forest dynamics are undergoing substantial changes because of the activity of the mainly European lumbricid species. Documented losses in litter layers, expansion of A-horizons, loss of the organic horizon, changes in fine root density, and shifts in microbial populations have all been documented in invaded zones. Two free air CO2 enrichment (FACE) forest experiments (aspen FACE at Rhinelander, Wisconsin and sweet gum FACE at Oak Ridge National Lab, Tennessee) lie within the zones of invasion and exhibit differences in amounts of exotic and native species as well as endogeic (predominantly mineral soil dwelling) and epigeic (litter and organic matter horizon dwelling) types. Considerations of carbon accrual dynamics and relative input of above vs. below ground plant input in these young successional systems do not consider the potential impact of these ecosystem engineers. We investigated the impact of earthworm activity by tracking the relative abundance and stable carbon isotope compositions of lignin and substituted fatty acids extracted from isolated earthworms and their fecal pellets and from host soils. Indications of root vs leaf input to earthworm casts and fecal matter were derived from differences in the chemical composition of cutin, suberin, and lignin. The isotopically depleted CO2 used in FACE and the resulting isotopically depleted plant organic matter afford an excellent opportunity to assess biopolymer-specific turnover dynamics. We find that endogeic species are proportionately more responsible for fine root cycling while some epigeic species are responsible for microaggregation of foliar cutin. CSIA of fecal pellet lignin and SFA indicates how these biopolymer pools can be derived from variable sources, roots, background soil, foliar tissue within one earthworm. Additionally, CSIA indicates the distinct roles that different earthworm types have in "aging" surface soil biopolymer pools through encapsulation and upward transport of deeper soil carbon, and "freshening" deeper soil biopolymer pools through downward transport of surface carbon to deeper layers,. As earthworm species abundance and activity are not is steady state in many forests, the role of these important invertebrates should be more considered when assessing the changing soil state.

  13. Measuring Experiential Avoidance in Adults: The Avoidance and Fusion Questionnaire

    ERIC Educational Resources Information Center

    Schmalz, Jonathan E.; Murrell, Amy R.

    2010-01-01

    To date, general levels of experiential avoidance are primarily measured by the Acceptance and Action Questionnaire-II (AAQ-II), but it includes items of questionable comprehensibility. The Avoidance and Fusion Questionnaire for Youth (AFQ-Y), previously validated as a measure of experiential avoidance with children and adolescents, was…

  14. Avoidable waste management costs

    SciTech Connect

    Hsu, K.; Burns, M.; Priebe, S.; Robinson, P.

    1995-01-01

    This report describes the activity based costing method used to acquire variable (volume dependent or avoidable) waste management cost data for routine operations at Department of Energy (DOE) facilities. Waste volumes from environmental restoration, facility stabilization activities, and legacy waste were specifically excluded from this effort. A core team consisting of Idaho National Engineering Laboratory, Los Alamos National Laboratory, Rocky Flats Environmental Technology Site, and Oak Ridge Reservation developed and piloted the methodology, which can be used to determine avoidable waste management costs. The method developed to gather information was based on activity based costing, which is a common industrial engineering technique. Sites submitted separate flow diagrams that showed the progression of work from activity to activity for each waste type or treatability group. Each activity on a flow diagram was described in a narrative, which detailed the scope of the activity. Labor and material costs based on a unit quantity of waste being processed were then summed to generate a total cost for that flow diagram. Cross-complex values were calculated by determining a weighted average for each waste type or treatability group based on the volume generated. This study will provide DOE and contractors with a better understanding of waste management processes and their associated costs. Other potential benefits include providing cost data for sites to perform consistent cost/benefit analysis of waste minimization and pollution prevention (WMIN/PP) options identified during pollution prevention opportunity assessments and providing a means for prioritizing and allocating limited resources for WMIN/PP.

  15. Combined toxicity of butachlor, atrazine and ?-cyhalothrin on the earthworm Eisenia fetida by combination index (CI)-isobologram method.

    PubMed

    Chen, Chen; Wang, Yanhua; Zhao, Xueping; Qian, Yongzhong; Wang, Qiang

    2014-10-01

    Pesticides in the environment do not appear singly and usually occur as complex mixtures and their combined effect may exhibit toxicity to organisms. The individual and combined toxicities of two herbicides, atrazine and butachlor and an insecticide ?-cyhalothrin have been examined to the earthworm Eisenia fetida, as a non-target terrestrial organism, in artificial soil and filter paper tests. The order of toxicity for the individual pesticides was ranked as atrazine>?-cyhalothrin>butachlor in both tests. We applied the combination index (CI)-isobologram method which is widely used to study chemical interactions to determine the nature of toxicological interactions of the pesticides and it allows computerized quantitation of synergism, additive effect and antagonism. For most cases in artificial soil test, synergism was observed in majority of the mixtures except for the combination of butachlor plus ?-cyhalothrin. This particular combination displayed opposite interaction in filter paper test. The CI method was compared with the classical models of Concentration Addition (CA) and Independent Action (IA) and we found that CI method could accurately predict the combined toxicity and can serve as a useful tool in ecotoxicological risk assessment. PMID:25048932

  16. Combined toxicities of methyl tert-butyl ether and its metabolite tert-butyl alcohol on earthworms via different exposure routes.

    PubMed

    Lee, Woo-Mi; Yoon, Youngdae; An, Youn-Joo

    2015-06-01

    Methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) are among the major soil contaminants that threaten the health of soil ecosystems. Many MTBE-contaminated sites accumulate TBA, because TBA is the intermediate of MTBE biodegradation. To access the risk of MTBE and TBA in soil, we investigated the combined toxicities of MTBE and TBA using two earthworm species, Perionyx excavatus and Eisenia andrei, as well as the toxic effects via different exposure routes. The combined toxicity showed weak antagonistic effects (LC50mix values were slightly greater than 1.0), and sensitivity toward same pollutants differed in the two earthworm species. Moreover, the toxicity of MTBE and TBA was also affected by the exposure route; both filter paper and artificial soil tests showed that dermal-only exposure to MTBE had an even greater toxic effect than combined dermal and oral exposure. Thus, we suggest that diverse environmental factors including organic materials, the physicochemical properties of the contact media, and the exposure routes of the organism, should be taken into consideration when assessing the effects of pollutants on organisms in diverse environmental systems. PMID:25706436

  17. Effect of volatile hydrocarbon fractions on mobility and earthworm uptake of polycyclic aromatic hydrocarbons from soils and soil/lampblack mixtures.

    PubMed

    Bogan, Bill W; Beardsley, Kate E; Sullivan, Wendy R; Hayes, Thomas D; Soni, Bhupendra K

    2005-01-01

    Studies were conducted to examine the mobility and bioavailability to earthworms (Eisenia fetida) of priority pollutant polycyclic aromatic hydrocarbons (PAH) in a suite of 11 soils and soil/lampblack mixtures obtained from former manufactured-gas plant sites. Contaminant mobility was assessed using XAD4 resins encapsulated in dialysis tubing, which were exposed to slurried soils for 15 d. These experiments showed that mobility of PAH in the different soils strongly correlated to the levels of volatile hydrocarbons (namely, gasoline- and diesel-range organics [GRO and DRO]) that existed in the soils as co-contaminants. Actual PAH bioavailability (as measured by earthworm PAH concentrations) also appeared to depend on GRO + DRO levels, although this was most evident at high levels of these contaminants. These findings are discussed in view of the effects of dieselrange organics on oil viscosity, assuming that the hydrocarbon contaminants in these soils exist in the form of distinct adsorbed oil phases. This study, therefore, extends correlations between carrier-oil viscosity and dissolved solute bioavailability, previously observed in a number of other in vitro and whole-organism tests (and in bacterial mutagenicity studies in soil), to multicellular organisms inhabiting contaminated-soil systems. PMID:15683182

  18. Acceleration of cellulose and organic matter decomposition as a result of earthworms effect on soil microbial community

    NASA Astrophysics Data System (ADS)

    Blagodatskaya, Evgenia; Khomyakov, Nikita; Blagodatsky, Sergey; Myachina, Olga; Byzov, Boris; Kuzyakov, Yakov

    2010-05-01

    The biotic activity of earthworms alters soil carbon turnover 1) indirectly by the disturbance of soil structure which increases the availability of organic matter; or 2) directly changing the structure of soil microbial community which is mainly in the dormant state in undisturbed soil. The activation of soil microorganisms by earthworms can strongly change the turnover of native soil organic matter (SOM), i.e. cause priming effects (PE). The effects of earthworms on mineralization of SOM and plant residues during PE induced by the input of available organic substances remains unclear. Our study aimed to evaluate how the microbial community modified by earthworms alters the decomposition of SOM and 14C-cellulose added to soil. Two-factorial experiment to assess the interactive effect of 1) earthworms Aporrectodea caliginosa and of 2) 14C-uniformly labeled cellulose on soil organic matter mineralization was carried out during 30 days incubation. The following variables were determined: 1) dynamics of CO2 evolution; 2) 14CO2 originated from the added cellulose; 3) microbial biomass C and 14C by fumigation-extraction; 4) specific growth rates of microorganisms by the kinetics of substrate induced respiration and 5) activities of extracellular enzymes (?-glucosidase, chitinase, cellobiogidrolase and xylanase) with fluorogenically labeled substrates. The experimental design allowed us to distinguish the contribution of different microbial communities to priming-effects, i.e. soil microbial community activated by cellulose; earthworms and their own microbial community; soil microbial community changed by earthworms. Maximal intensity of CO2 and 14CO2 efflux as well as of enzyme activities was observed between 5th and 15th days after cellulose application. Contribution of earthworms to total soil respiration (calculated as difference between CO2 efflux from soil with and without earthworms) amounted up to 60%. Earthworms accelerated SOM decomposition for 50% while cellulose mineralization was accelerated by A. caliginosa for 15.8 % as compared to soil without earthworms. Increased activity of enzymes which release monomer units from polymeric chains (?-glucosidase for 32 % and chitinase for 19 %) was observed in the presence of earthworms in soil. However, strong decrease in activity of cellulolytic enzymes: xylanase (for 25 %) and especially of cellobiogidrolase ( for 87 %) was caused by A. caliginosa in 15 days after cellulose addition. The maximal specific growth rates of soil microorganisms were 20 - 30 % lower in soil with application of earthworms as compared with worms-free soil. No significant effect of earthworms on total microbial biomass C was observed. However, the changes in microbial growth kinetics as well as in enzyme activities prove the shift in microbial community structure to domination of slow growing K-strategists caused by earthworms. We conclude that earthworms strongly affect soil microbial populations resulting in accelerated decomposition of both SOM and plant residues.

  19. Bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure

    USGS Publications Warehouse

    Kinney, C.A.; Furlong, E.T.; Kolpin, D.W.; Burkhardt, M.R.; Zaugg, S.D.; Werner, S.L.; Bossio, J.P.; Benotti, M.J.

    2008-01-01

    Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied biosolids and livestock manure to earthworms. The sites consisted of a soybean field with no amendments of human or livestock waste (Site 1), a soybean field amended with biosolids from a municipal wastewater treatment plant (Site 2), and a cornfield amended with swine manure (Site 3). The biosolid applied to Site 2 contained a diverse composition of 28 AWIs, reflecting the presence of human-use compounds. The swine manure contained 12 AWIs, and was dominated by biogenic sterols. Soil and earthworm samples were collected in the spring (about 30 days after soil amendment) and fall (140-155 days after soil amendment) at all field sites. Soils from Site 1 contained 21 AWIs and soil from Sites 2 and 3 contained 19 AWIs. The AWI profiles at Sites 2 and 3 generally reflected the relative composition of AWIs present in waste material applied. There were 20 AWIs detected in earthworms from Site 1 (three compounds exceeding concentrations of 1000 ??g/kg), 25 AWIs in earthworms from Site 2 (seven compounds exceeding concentrations of 1000 ??g/kg), and 21 AWIs in earthworms from Site 3 (five compounds exceeding concentrations of 1000 ??g/kg). A number of compounds thatwere present in the earthworm tissue were at concentrations less than reporting levels in the corresponding soil samples. The AWIs detected in earthworm tissue from the three field sites included pharmaceuticals, synthetic fragrances, detergent metabolites, polycyclic aromatic hydrocarbons (PAHs), biogenic sterols, disinfectants, and pesticides, reflecting a wide range of physicochemical properties. For those contaminants detected in earthworm tissue and soil, bioaccumulation factors (BAF) ranged from 0.05 (galaxolide) to 27 (triclosan). This study documents that when AWIs are present in source materials that are land applied, such as biosolids and swine manure, AWIs can be transferred to earthworms. ?? 2008 American Chemical Society.

  20. Avoiding dangerous climate change

    SciTech Connect

    Hans Joachim Schellnhuber; Wolfgang Cramer; Nebojsa Nakicenovic; Tom Wigley; Gary Yohe (eds.)

    2006-02-15

    In 2005 the UK Government hosted the Avoiding Dangerous Climate Change conference to take an in-depth look at the scientific issues associated with climate change. This volume presents the most recent findings from the leading international scientists that attended the conference. The topics addressed include critical thresholds and key vulnerabilities of the climate system, impacts on human and natural systems, socioeconomic costs and benefits of emissions pathways, and technological options for meeting different stabilisation levels of greenhouse gases in the atmosphere. Contents are: Foreword from Prime Minister Tony Blair; Introduction from Rajendra Pachauri, Chairman of the IPCC; followed by 41 papers arranged in seven sections entitled: Key Vulnerabilities of the Climate System and Critical Thresholds; General Perspectives on Dangerous Impacts; Key Vulnerabilities for Ecosystems and Biodiversity; Socio-Economic Effects; Regional Perspectives; Emission Pathways; and Technological Options. Four papers have been abstracted separately for the Coal Abstracts database.

  1. Carbon and nitrogen stable isotope ratios in body tissue and mucus of feeding and fasting earthworms ( Lumbricus festivus )

    Microsoft Academic Search

    Olaf Schmidt; Charles M. Scrimgeour; James P. Curry

    1999-01-01

    We used natural abundance stable isotope techniques to estimate carbon and nitrogen turnover rates in body tissue and mucus\\u000a of earthworms. Isotope ratios of carbon (?13C) and nitrogen (?15N) were monitored simultaneously in body tissue and mucus for up to 101?days in feeding or fasting Lumbricus festivus kept in an artificial substrate. When the diet of the earthworms was switched

  2. Multielement determination in earthworms with instrumental neutron activation analysis and inductively coupled plasma mass spectrometry: A comparison

    Microsoft Academic Search

    Jian Zheng; W. Goessler; A. Geiszinger; W. Kosmus; Baolin Chert; Guisun Zhuang; Kai Xu; Guoping Sui

    1997-01-01

    Earthworms were collected from agricultural fields in Admont, Graz, Piber and Gumpenstein, Austria. Six earthworm samples were investigated with INAA and with ICP-MS in parallel for the element concentrations of As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Pb, Rb, Sb, Se and Zn. With both techniques 14 elements were analysed in a wide concentration range (ng\\/g to mg\\/g) GF-AAS

  3. Sampling of resident earthworms using mustard expellant to evaluate ecological risk at a mixed hazardous and radioactive waste site

    SciTech Connect

    Stair, D.M. Jr.; Keller, L.J. [Bechtel Environmental Inc., Oak Ridge, TN (United States). Oak Ridge Remediation Center; Hensel, T.W. [OGDEN Environmental and Energy Services, Inc., Oak Ridge, TN (United States)

    1994-12-31

    As residents of contaminated soils and as prey for many species of wildlife, earthworms can serve as integrative biomonitors of soil contamination, which is biologically available to the terrestrial food chain. The assessment of contaminants within earthworm tissue provides a more realistic measurement of the potential biological hazards and ecological risks than physical and chemical measurements of soil. A unique sampling procedure using a mixture of ground mustard powder and water was implemented for cost-effectively collecting earthworms without digging; the procedure minimized occupational exposure to soil contaminants and reduced the quantity of investigation-derived wastes. The study site is located at a closed burial ground for low-level radioactive waste and transuranic waste that lies within the Valley and Ridge Physiographic Province of East Tennessee. Earthworms were maintained in the laboratory for four days to allow passage of the contents of the digestive tract. Earthworm body burdens, castings, and soil were analyzed for gamma-emitting radioisotopes (potassium 40, cobalt 60, cesium 137), strontium 90, trace metals (arsenic, cadmium, chromium, mercury, lead, and selenium), and polychlorinated biphenyls (PCBs). Ecological effects of soil contamination on the earthworms were also assessed through analysis of weight, abundance, and reproductive success.

  4. AVOIDANCE BEHAVIOR OF MALLARDS AND NORTHERN BOBWHITE EXPOSED TO CARBOFURAN-CONTAMINATED FOOD AND WATER

    EPA Science Inventory

    Food avoidance experiments could contribute to assessments of animals' behavioral responses to environmental toxicants. ood avoidance tests with mallards (Anas platyrhynchos L.) and northern bobwhite (Colinus virginianus L.) as the test species were patterned after avian 5-d diet...

  5. The Earthworm Gut: an Ideal Habitat for Ingested N2O-Producing Microorganisms

    PubMed Central

    Horn, Marcus A.; Schramm, Andreas; Drake, Harold L.

    2003-01-01

    The in vivo production of nitrous oxide (N2O) by earthworms is due to their gut microbiota, and it is hypothesized that the microenvironment of the gut activates ingested N2O-producing soil bacteria. In situ measurement of N2O and O2 with microsensors demonstrated that the earthworm gut is anoxic and the site of N2O production. The gut had a pH of 6.9 and an average water content of approximately 50%. The water content within the gut decreased from the anterior end to the posterior end. In contrast, the concentration of N2O increased from the anterior end to the mid-gut region and then decreased along the posterior part of the gut. Compared to the soil in which worms lived and fed, the gut of the earthworm was highly enriched in total carbon, organic carbon, and total nitrogen and had a C/N ratio of 7 (compared to a C/N ratio of 12 in soil). The aqueous phase of gut contents contained up to 80 mM glucose and numerous compounds that were indicative of anaerobic metabolism, including up to 9 mM formate, 8 mM acetate, 3 mM lactate, and 2 mM succinate. Compared to the soil contents, nitrite and ammonium were enriched in the gut up to 10- and 100-fold, respectively. The production of N2O by soil was induced when the gut environment was simulated in anoxic microcosms for 24 h (the approximate time for passage of soil through the earthworm). Anoxia, high osmolarity, nitrite, and nitrate were the dominant factors that stimulated the production of N2O. Supplemental organic carbon had a very minimal stimulatory effect on the production of N2O, and addition of buffer or ammonium had essentially no effect on the initial N2O production rates. However, a combination of supplements yielded rates greater than that obtained mathematically for single supplements, suggesting that the maximum rates observed were due to synergistic effects of supplements. Collectively, these results indicate that the special microenvironment of the earthworm gut is ideally suited for N2O-producing bacteria and support the hypothesis that the in situ conditions of the earthworm gut activate ingested N2O-producing soil bacteria during gut passage. PMID:12620857

  6. Affordable MMW aircraft collision avoidance system

    NASA Astrophysics Data System (ADS)

    Almsted, Larry D.; Becker, Robert C.; Zelenka, Richard E.

    1997-06-01

    Collision avoidance is of concern to all aircraft, requiring the detection and identification of hazardous terrain or obstacles in sufficient time for clearance maneuvers. The collision avoidance requirement is even more demanding for helicopters, as their unique capabilities result in extensive operations at low-altitude, near to terrain and other hazardous obstacles. TO augment the pilot's visual collision avoidance abilities, some aircraft are equipped with 'enhanced-vision' systems or terrain collision warning systems. Enhanced-vision systems are typically very large and costly systems that are not very covert and are also difficult to install in a helicopter. The display is typically raw images from infrared or radar sensors, and can require a high degree of pilot interpretation and attention. Terrain collision warning system that rely on stored terrain maps are often of low resolution and accuracy and do not represent hazards to the aircraft placed after map sampling. Such hazards could include aircraft parked on runway, man- made towers or buildings and hills. In this paper, a low cost dual-function scanning pencil-beam, millimeter-wave radar forward sensor is used to determine whether an aircraft's flight path is clear of obstructions. Due to the limited space and weight budget in helicopters, the system is a dual function system that is substituted in place of the existing radar altimeter. The system combines a 35 GHz forward looking obstacle avoidance radar and a 4.3 GHz radar altimeter. The forward looking 35 GHz 3D radar's returns are used to construct a terrain and obstruction database surrounding an aircraft, which is presented to the pilot as a synthetic perspective display. The 35 GHz forward looking radar and the associated display was evaluated in a joint NASA Honeywell flight test program in 1996. The tests were conducted on a NASA/Army test helicopter. The test program clearly demonstrated the systems potential usefulness for collision avoidance.

  7. Collision avoidance sensor skin

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The objective was to totally eliminate the possibility of a robot (or any mechanism for that matter) inducing a collision in space operations. We were particularly concerned that human beings were safe under all circumstances. This was apparently accomplished, and it is shown that GSFC has a system that is ready for space qualification and flight. However, it soon became apparent that much more could be accomplished with this technology. Payloads could be made invulnerable to collision avoidance and the blind spots behind them eliminated. This could be accomplished by a simple, non-imaging set of 'Capaciflector' sensors on each payload. It also is evident that this system could be used to align and dock the system with a wide margin of safety. Throughout, lighting problems could be ignored, and unexpected events and modeling errors taken in stride. At the same time, computational requirements would be reduced. This can be done in a simple, rugged, reliable manner that will not disturb the form factor of space systems. It will be practical for space applications. The lab experiments indicate we are well on the way to accomplishing this. Still, the research trail goes deeper. It now appears that the sensors can be extended to end effectors to provide precontact information and make robot docking (or any docking connection) very smooth, with minimal loads impacted back into the mating structures. This type of ability would be a major step forward in basic control techniques in space. There are, however, baseline and restructuring issues to be tackled. The payloads must get power and signals to them from the robot or from the astronaut servicing tool. This requires a standard electromechanical interface. Any of several could be used. The GSFC prototype shown in this presentation is a good one. Sensors with their attendant electronics must be added to the payloads, end effectors, and robot arms and integrated into the system.

  8. Behavioural inbreeding avoidance in wild African elephants.

    PubMed

    Archie, Elizabeth A; Hollister-Smith, Julie A; Poole, Joyce H; Lee, Phyllis C; Moss, Cynthia J; Maldonado, Jésus E; Fleischer, Robert C; Alberts, Susan C

    2007-10-01

    The costs of inbreeding depression, as well as the opportunity costs of inbreeding avoidance, determine whether and which mechanisms of inbreeding avoidance evolve. In African elephants, sex-biased dispersal does not lead to the complete separation of male and female relatives, and so individuals may experience selection to recognize kin and avoid inbreeding. However, because estrous females are rare and male-male competition for mates is intense, the opportunity costs of inbreeding avoidance may be high, particularly for males. Here we combine 28 years of behavioural and demographic data on wild elephants with genotypes from 545 adult females, adult males, and calves in Amboseli National Park, Kenya, to test the hypothesis that elephants engage in sexual behaviour and reproduction with relatives less often than expected by chance. We found support for this hypothesis: males engaged in proportionally fewer sexual behaviours and sired proportionally fewer offspring with females that were natal family members or close genetic relatives (both maternal and paternal) than they did with nonkin. We discuss the relevance of these results for understanding the evolution of inbreeding avoidance and for elephant conservation. PMID:17784925

  9. Avoidance of Phycomyces in a controlled environment.

    PubMed Central

    Meyer, P W; Matus, I J; Berg, H C

    1987-01-01

    The sporangiophore of the fungus Phycomyces bends away from nearby objects without ever touching them. It has been thought that these objects act as aerodynamic obstacles that damp random winds, thereby generating asymmetric distributions of a growth-promoting gas emitted by the growth zone. In the interest of testing this hypothesis, we studied avoidance in an environmental chamber in which convection was suppressed by a shallow thermal gradient. We also controlled pressure, temperature, and relative humidity of the air, electrostatic charge, and ambient light. A protocol was established that yielded avoidance rates constant from sporangiophore to sporangiophore to within +/- 10%. We found that avoidance occurred at normal rates in the complete absence of random winds. The rates were smaller at 100% than at lower values of relative humidity, but not by much. Remarkably, at a distance as great as 0.5 mm, avoidance from a 30-micron diam glass fiber (aligned parallel to the sporangiophore) was about the same as that from a planar glass sheet. However, the rate for the fiber fell more rapidly with distance. The rate for the sheet remained nearly constant out to approximately 4 mm. We conclude that avoidance depends either on adsorption by the barrier of a growth-inhibiting substance or emission by the barrier of a growth-promoting substance; it cannot occur by passive reflection. Models that can explain these effects are analyzed in the Appendix. PMID:3567313

  10. A comparison of multiple esterases as biomarkers of organophosphate exposure and effect in two earthworm species.

    PubMed

    Henson-Ramsey, Heather; Schneider, Ashley; Stoskopf, Michael K

    2011-04-01

    Two different earthworm species, Eisenia fetida and Lumbricus terrestris, were exposed to 5 ?g/cm(2) of malathion to evaluate their usefulness as sentinels of organophosphate exposure and to assess three different esterases, as biomarkers of malathion exposure and effect. Tissue xenobiotic burdens and esterase activity were determined for each species and each esterase in order to assess variability. E. fetida exhibited 4-fold less variability in tissue burdens than did L. terrestris and had less variable basal esterase activities. An attempt was made to correlate malathion and malaoxon tissue burdens with esterase activity post-exposure. There was no malaoxon present in the earthworm tissues. No significant correlations were determined by comparing acetylcholinesterase, butyrylcholinesterase, nor carboxylesterase activities with malathion burdens. PMID:21404045

  11. Parasitism and growth in the earthworm Lumbricus terrestris: fitness costs of the gregarine parasite Monocystis sp.

    PubMed

    Field, S G; Michiels, N K

    2005-04-01

    Parasites inflict fitness costs on their hosts, but often the exact reduction in fitness is not well understood. We investigated the influence of infection by the gregarine genus Monocystis sp. on growth and female investment (cocoon production) of its earthworm host, Lumbricus terrestris. Earthworms (n = 81) were observed in a laboratory setting for 8 months, after which parasite load was determined. The results revealed a significant negative relationship between parasite load and growth, yet no association to cocoon production was found. Although the exact nature, strength, and evolutionary consequence of reduced growth are still unclear, the results are the first indication for a clear, albeit weak effect of Monocystis on host fitness. PMID:15830813

  12. Uptake, bioavailability and elimination of hydrophobic compounds in earthworms (Eisenia andrei) in field-contaminated soil

    SciTech Connect

    Belfroid, A.; Berg, M. van den; Seinen, W.; Hermens, J. [Univ. of Utrecht (Netherlands). Research Inst. of Toxicology; Gestel, K. van [Vrije Univ., Amsterdam (Netherlands). Dept. of Ecology and Ecotoxicology

    1995-04-01

    Uptake, accumulation, and elimination of hydrophobic organic chemicals in earthworms (Eisenia andrei) exposed to field-contaminated Volgermeerpolder soil was studied. Earthworms were able to take up chlorobenzenes and polychlorobiphenyls (PCBs), but body burdens did not exceed concentrations measured in the soil. For the chlorobenzenes, steady-state concentrations in the worms and biota-to-soil accumulation factor (BSAF) values were much smaller than expected based on earlier experiments, suggesting a decreased bioavailability in the Volgermeerpolder soil. Comparison of the PCB accumulation pattern in worms to the pattern in soil showed that biotransformation of the studied PCBs is of minor importance in this species. Elimination of all chemicals studied was monophasic, with the exception of hexachlorobenzene, which showed a biphasic elimination. The elimination half-life for the initial fast phase of this compound is comparable to the elimination measured in previous studies. Elimination rate constants decreased with increasing log K{sub ow}.

  13. Soil Bioremediation: Combination of Earthworms and Compost for the Ecological Remediation of a Hydrocarbon Polluted Soil

    Microsoft Academic Search

    Brunello Ceccanti; Grazia Masciandaro; Carlos Garcia; Cristina Macci; Serena Doni

    2006-01-01

    The present investigation, carried out in laboratory microcosms, regards the effects of some bioremediation treatments of a polluted soil and the use of specific parameters to study the evolution of biochemical processes which take place in the soil decontamination.The bioremediation treatments were the following: 1) a mixture of microorganisms-enzymes-nutrients (MEN); 2); compost alone (C); 3) compost with earthworms (Eisenia fetida)

  14. A novel antimicrobial peptide from skin secretions of the earthworm, Pheretima guillelmi (Michaelsen)

    Microsoft Academic Search

    Wenliang Li; Sisi Li; Jian Zhong; Zhu Zhu; Jingze Liu; Wenhong Wang

    2011-01-01

    A novel lumbricin-like antimicrobial peptide named lumbricin-PG was isolated from skin secretions of the earthworm, Pheretima guillelmi (Michaelsen), using a procedure of one step Sephadex G-50 gel filtration and one step C8 reverse-phase high-performance liquid chromatography (RP-HPLC). Its amino acid sequence was determined as FSRYARMRDSRPWSDRKNNYSGPQFTYPPEKAPPEKLIKWNN EGSPIFEMPAEGGHIEP by Edman degradation combined with cDNA cloning and mass spectrometry analysis. The cDNA encoding

  15. Production of vermifertilizer from guar gum industrial wastes by using composting earthworm Perionyx sansibaricus (Perrier)

    Microsoft Academic Search

    Surendra Suthar

    2007-01-01

    Efforts have been made to convert the guar gum industrial waste into a value-added product, by employing a new earthworm species\\u000a for vermicomposting e.g. Perionyx sansibaricus (Perrier) (Megascolecidae), under laboratory conditions. Industrial lignocellulosic waste was amended with other organic\\u000a supplements (saw dust and cow dung); and three types of vermibeds were prepared: guar gum industrial waste + cow dung + saw\\u000a dust in 40:

  16. Earthworm effects on N dynamics and soil respiration in microcosms receiving organic and inorganic nutrients

    Microsoft Academic Search

    Patrick J. Bohlen; Clive A. Edwards

    1995-01-01

    We designed a microcosm experiment to investigate the effects of earthworms on N cycling processes and microbial activity, in soil receiving organic or inorganic nutrient amendments. Cylindrical microcosms contained 16l. of field-collected soil that received 1 of 3 nutrient amendments, added to the upper 5 cm of soil at a rate of 150 kg N ha?1; (1) granular NH4NO3 fertilizer;

  17. Development of a Dynamic Pharmacokinetic Model to Estimate Bioconcentration of Xenobiotics in Earthworms

    Microsoft Academic Search

    Heather Henson-Ramsey; Jay Levine; Suzanne Kennedy-Stoskopf; Sharon K. Taylor; Damian Shea; Michael K. Stoskopf

    2009-01-01

    A simple and dynamic pharmacokinetic model was developed to predict bioconcentration of organic contaminants in earthworms.\\u000a The model was parameterized experimentally by placing Lumbricus terrestris in soil contaminated with 200 µg\\/cm2 of malathion. The toxicokinetics of malathion uptake, depuration, and degradation in soil is measured. After parameterization,\\u000a the model was able to accurately predict the bioconcentration factor of malathion at steady

  18. Effect of malathion on the male reproductive organs of earthworms, Eisenia foetida

    Microsoft Academic Search

    Omar Espinoza-Navarro; Eduardo Bustos-Obregón

    2005-01-01

    Aim:To observe the cytotoxic effect of the organophosphate insecticide malathion in the reproductive tissues of the earthworms, Eisenia foetida.Methods:Worms were nourished in soil treated with malathion at single sub-lethal doses of 0, 80, 150, 300 and 600 mg·kg?1 soil. (LD50= 880 mg·kg?1 soil) and evaluated on days 1, 5, 15 and 30 after exposure. The body weights were recorded and

  19. A Comparison of Multiple Esterases as Biomarkers of Organophosphate Exposure and Effect in Two Earthworm Species

    Microsoft Academic Search

    Heather Henson-Ramsey; Ashley Schneider; Michael K. Stoskopf

    2011-01-01

    Two different earthworm species, Eisenia fetida and Lumbricus terrestris, were exposed to 5 ?g\\/cm2 of malathion to evaluate their usefulness as sentinels of organophosphate exposure and to assess three different esterases,\\u000a as biomarkers of malathion exposure and effect. Tissue xenobiotic burdens and esterase activity were determined for each species\\u000a and each esterase in order to assess variability. E. fetida exhibited 4-fold

  20. The effect of earthworms on the physiological state of the microbial community at vermicomposting

    Microsoft Academic Search

    A. V. Yakushev; S. A. Blagodatsky; B. A. Byzov

    2009-01-01

    The effect of earthworms on the microbial community of composts and vermicomposts was assayed by the following parameters:\\u000a mineralization activity, the levels of physiologically active and growing microbial biomass, the requirement for growth factors,\\u000a and the spectrum of assimilation of organic substrates by the microbial community. The substrate affinities of microbial enzyme\\u000a systems in vermicompost were found to be lower

  1. Lead bioaccumulation in earthworms, Lumbricus terrestris, from exposure to lead compounds of differing solubility

    Microsoft Academic Search

    Colin T. R. Darling; Vernon G. Thomas

    2005-01-01

    This study examined the relative effects of soluble and less soluble Pb compounds on Pb accumulation by Lumbricus terrestris. The earthworms were exposed to composted cattle manure contaminated with a range of concentrations of either soluble lead acetate trihydrate (PbAc) (14.5, 72.2, 137, 257, and 603 ?g\\/g) or less soluble lead carbonate (Pb(CO3)2) (5.09, 171, 575, and 710 ?g\\/g). Relative

  2. Recycling of spent mushroom compost using earthworms Eisenia foetida and Eisenia andrei

    Microsoft Academic Search

    J. Tajbakhsh; M. A. Abdoli; E. Mohammadi Goltapeh; I. Alahdadi; M. J. Malakouti

    2008-01-01

    A 90-day study conducted to explore the potential of epigeic earthworms Eisenia foetida and Eisenia andrei to transform the different types of agricultural wastes and spent mushroom compost into value-added product, i.e., vermicompost.\\u000a Vermicomposting resulted in significant reduction in C:N ratio, pH, electrical conductivity, total organic carbon, TK; and\\u000a increase in total Kajeldahl nitrogen, TP, and various micro and macronutrients

  3. Effects of HMX-Lead Mixtures on Reproduction of the Earthworm Eisenia Andrei

    Microsoft Academic Search

    Kathleen Savard; Yann Berthelot; Aurelie Auroy; Philip A. Spear; Bertin Trottier; Pierre Yves Robidoux

    2007-01-01

    High metal (e.g., Pb) concentrations are typically found in explosive-contaminated soil, and their presence may increase, decrease, or not\\u000a influence toxicity predicted on the basis of one explosive alone (e.g., HMX). Nevertheless, few data are available in the scientific literature for this type of multiple exposure. Soil organisms,\\u000a such as earthworms, are one of the first receptors affected by the

  4. Relationships between spatial pattern of the endogeic earthworm Polypheretima elongata and soil heterogeneity

    Microsoft Academic Search

    Jean-Pierre Rossi; Patrick Lavelle; Alain Albrecht

    1997-01-01

    Spatial distribution of the endogeic earthworm Polypheretima elongata, soil texture, carbon and nitrogen contents were investigated in a 10-y-old pasture established on a vertisol, by measuring each variable at 57 points randomly located in a 25 × 60 m plot. Soil variables were measured at three depths: 0–10, 10–20 and 20–30 cm. Principal component analysis (PCA) of the data set

  5. Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables.

    PubMed

    Falco, L B; Sandler, R; Momo, F; Di Ciocco, C; Saravia, L; Coviella, C

    2015-01-01

    The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological soil variables that are associated to the observed differences. Three soil uses were evaluated: 1-Fifty year old naturalized grasslands, low use intensity; 2-Recent agricultural fields, intermediate use intensity, and 3-Fifty year old intensive agricultural fields, high use intensity. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in relative abundance by soil use. The results show that the earthworm community structure is linked to and modulated by soil properties. Both species abundance and diversity showed significant differences depending on soil use intensity. A principal component analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance systems. Microscolex dubius abundance was related to naturalized grasslands along with soil Ca, pH, mechanical resistance, and microbial respiration. Aporrectodea caliginosa abundance was related to high K levels, low enzymatic activity, slightly low pH, low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found in the recent agricultural system, were related to high soil moisture condition, low pH, low Ca and low enzymatic activity. These results show that earthworm assemblages can be good indicators of soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea, showed different temporal patterns and species associations, due to the changes in soil properties attributable to soil use intensity, defined as the amount and type of agricultural operations. PMID:26038733

  6. Neurochemical and electrophysiological diagnosis of reversible neurotoxicity in earthworms exposed to sublethal concentrations of CL20

    Microsoft Academic Search

    Ping Gong; Niladri Basu; Anton M. Scheuhammer; Edward J. Perkins

    2010-01-01

    Background, aim, and scope  Hexanitrohexaazaisowurtzitane (CL-20) is a relatively new energetic compound sharing some degree of structural similarity\\u000a with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), a known neurotoxic compound. Previously, we demonstrated using a noninvasive\\u000a electrophysiological technique that CL-20 was a more potent neurotoxicant than RDX to the earthworm Eisenia fetida. In the present study, we investigated the effect of CL-20 exposure and subsequent recovery

  7. Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables

    PubMed Central

    Sandler, R; Momo, F; Di Ciocco, C; Saravia, L; Coviella, C

    2015-01-01

    The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological soil variables that are associated to the observed differences. Three soil uses were evaluated: 1-Fifty year old naturalized grasslands, low use intensity; 2-Recent agricultural fields, intermediate use intensity, and 3-Fifty year old intensive agricultural fields, high use intensity. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in relative abundance by soil use. The results show that the earthworm community structure is linked to and modulated by soil properties. Both species abundance and diversity showed significant differences depending on soil use intensity. A principal component analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance systems. Microscolex dubius abundance was related to naturalized grasslands along with soil Ca, pH, mechanical resistance, and microbial respiration. Aporrectodea caliginosa abundance was related to high K levels, low enzymatic activity, slightly low pH, low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found in the recent agricultural system, were related to high soil moisture condition, low pH, low Ca and low enzymatic activity. These results show that earthworm assemblages can be good indicators of soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea, showed different temporal patterns and species associations, due to the changes in soil properties attributable to soil use intensity, defined as the amount and type of agricultural operations. PMID:26038733

  8. Assessment of the Genotoxicity of Endosulfan in Earthworm and White Clover Plants Using the Comet Assay

    Microsoft Academic Search

    Wei Liu; Lu-Sheng Zhu; Jun Wang; Jin-Hua Wang; Hui Xie; Yan Song

    2009-01-01

    Endosulfan, as one of the most widely used organochlorine pesticides in the world, has increased the public concern about\\u000a genotoxicity in soil ecosystems. The comet assay has been widely used in the fields of genetic toxicology and environmental\\u000a biomonitoring. In the present study we conducted comet assay of endosulfan in earthworm (Eisenia foetida) and white clover (Trifolium repens L.), which

  9. Earthworm communities in native savannas and man-made pastures of the Eastern Plains of Colombia

    Microsoft Academic Search

    J. J. Jiménez; A. G. Moreno; T. Decaëns; P. Lavelle; M. J. Fisher; R. J. Thomas

    1998-01-01

    The structure and seasonal changes of earthworm communities were evaluated in a natural savanna and in a improved grass-legume\\u000a pasture in a Colombian oxisol over a period of 18 months. One plot of 90×90 m was isolated in each of the systems and each\\u000a month five samples of 1 m2×0.5 m and ten of 20×20×20 cm were randomly selected from

  10. The Effect of Tributyltin-Oxide on Earthworms, Springtails, and Plants in Artificial and Natural Soils

    Microsoft Academic Search

    J. Römbke; S. Jänsch; T. Junker; B. Pohl; A. Scheffczyk; H.-J. Schallnaß

    2007-01-01

    Chemical bioavailability in Organisation for Economic Co-operation and Development (OECD) artificial soil can contrast with\\u000a bioavailability in natural soils and produce ecotoxicologic benchmarks that are not representative of species’ exposure conditions\\u000a in the field. Initially, reproduction and growth of earthworm and Collembolan species, and early seedling growth of a dicotyledonous\\u000a plant species, in nine natural soils (with a wide range

  11. Community-specific impacts of exotic earthworm invasions on soil carbon dynamics in a sandy temperate forest.

    PubMed

    Crumsey, Jasmine M; Le Moine, James M; Capowiez, Yvan; Goodsitt, Mitchell M; Larson, Sandra C; Kling, George W; Nadelhoffer, Knute J

    2013-12-01

    Exotic earthworm introductions can alter above- and belowground properties of temperate forests, but the net impacts on forest soil carbon (C) dynamics are poorly understood. We used a mesocosm experiment to examine the impacts of earthworm species belonging to three different ecological groups (Lumbricus terrestris [anecic], Aporrectodea trapezoides [endogeic], and Eisenia fetida [epigeic]) on C distributions and storage in reconstructed soil profiles from a sandy temperate forest soil by measuring CO2 and dissolved organic carbon (DOC) losses, litter C incorporation into soil, and soil C storage with monospecific and species combinations as treatments. Soil CO2 loss was 30% greater from the Endogeic x Epigeic treatment than from controls (no earthworms) over the first 45 days; CO2 losses from monospecific treatments did not differ from controls. DOC losses were three orders of magnitude lower than CO2 losses, and were similar across earthworm community treatments. Communities with the anecic species accelerated litter C mass loss by 31-39% with differential mass loss of litter types (Acer rubrum > Populus grandidentata > Fagus grandifolia > Quercus rubra > or = Pinus strobus) indicative of leaf litter preference. Burrow system volume, continuity, and size distribution differed across earthworm treatments but did not affect cumulative CO2 or DOC losses. However, burrow system structure controlled vertical C redistribution by mediating the contributions of leaf litter to A-horizon C and N pools, as indicated by strong correlations between (1) subsurface vertical burrows made by anecic species, and accelerated leaf litter mass losses (with the exception of P. strobus); and (2) dense burrow networks in the A-horizon and the C and N properties of these pools. Final soil C storage was slightly lower in earthworm treatments, indicating that increased leaf litter C inputs into soil were more than offset by losses as CO2 and DOC across earthworm community treatments. PMID:24597228

  12. Persistence and changes in bioavailability of dieldrin, DDE, and heptachlor epoxide in earthworms over 45 years.

    PubMed

    Beyer, W Nelson; Gale, Robert W

    2013-02-01

    The finding of dieldrin (88 ng/g), DDE (52 ng/g), and heptachlor epoxide (19 ng/g) in earthworms from experimental plots after a single moderate application (9 kg/ha) 45 years earlier attests to the remarkable persistence of these compounds in soil and their continued uptake by soil organisms. Half-lives (with 95 % confidence intervals) in earthworms, estimated from exponential decay equations, were as follows: dieldrin 4.9 (4.3-5.7) years, DDE 5.3 (4.7-6.1) years, and heptachlor epoxide 4.3 (3.8-4.9) years. These half-lives were not significantly different from those estimated after 20 years. Concentration factors (dry weight earthworm tissue/dry weight soil) were initially high and decreased mainly during the first 11 years after application. By the end of the study, average concentration factors were 1.5 (dieldrin), 4.0 (DDE), and 1.8 (heptachlor epoxide), respectively. PMID:23001942

  13. Effect of biochar amendment on the bioavailability of pesticide chlorantraniliprole in soil to earthworm.

    PubMed

    Wang, Ting-Ting; Cheng, Jie; Liu, Xian-Jin; Jiang, Wayne; Zhang, Chao-Lan; Yu, Xiang-Yang

    2012-09-01

    To evaluate the effect of biochar amendment on the bioavailability of chlorantraniliprole (CAP) in soils with different physico-chemical properties, the uptake of CAP from various soils by earthworms was studied. It was observed that the biochar amendment of the soils affected the sorption of CAP, but the magnitude of the sorption enhancement by biochar amendment among the soils was varied, presumably due to the attenuation of the sorptivity of the biochar when amended in the soil. The amendment with biochars leads to a decrease in the bioavailability of CAP in the soils to earthworms, and more prominent for biochar BC850 amendment. In the soil with a CAP concentration of 10 mg kg(-1), the residue of CAP in the earthworm tissues was found to be 9.65 mg kg(-1), in comparison with that the CAP residue was 4.05 mg kg(-1) in BC450 amended soil and 0.59 mg kg(-1) in BC850, respectively. The degree of bioavailability reduction by same level of biochar amendment was different among soils with different properties. The results demonstrate that the properties of soils are important to performance of biochar in soil. PMID:22776710

  14. The earthworm—Verminephrobacter symbiosis: an emerging experimental system to study extracellular symbiosis

    PubMed Central

    Lund, Marie B.; Kjeldsen, Kasper U.; Schramm, Andreas

    2014-01-01

    Almost all Lumbricid earthworms (Oligochaeta: Lumbricidae) harbor extracellular species-specific bacterial symbionts of the genus Verminephrobacter (Betaproteobacteria) in their nephridia. The symbionts have a beneficial effect on host reproduction and likely live on their host's waste products. They are vertically transmitted and presumably associated with earthworms already at the origin of Lumbricidae 62–136 million years ago. The Verminephrobacter genomes carry signs of bottleneck-induced genetic drift, such as accelerated evolutionary rates, low codon usage bias, and extensive genome shuffling, which are characteristic of vertically transmitted intracellular symbionts. However, the Verminephrobacter genomes lack AT bias, size reduction, and pseudogenization, which are also common genomic hallmarks of vertically transmitted, intracellular symbionts. We propose that the opportunity for genetic mixing during part of the host—symbiont life cycle is the key to evade drift-induced genome erosion. Furthermore, we suggest the earthworm-Verminephrobacter association as a new experimental system for investigating host-microbe interactions, and especially for understanding genome evolution of vertically transmitted symbionts in the presence of genetic mixing. PMID:24734029

  15. Flow cytometric quantification of proliferating coelomocytes non-invasively retrieved from the earthworm, Dendrobaena veneta.

    PubMed

    Homa, Joanna; Bzowska, Malgorzata; Klimek, Malgorzata; Plytycz, Barbara

    2008-01-01

    Earthworms irritated naturally (e.g. by predators) or experimentally extrude coelomocyte-containing coelomic fluid through the dorsal pores of the body wall. In the present study, the earthworms, Dendrobaena veneta, experimentally depleted of free-floating coelomocytes by multiple electric shocks (1 min, 4.5 V) remained fully vital and coelomocyte depletion was followed by the extensive cell replenishment, which was more efficient in the case of amoebocytes than autofluorescent eleocytes/chloragocytes, quantified by flow cytometry. Immunohistochemical procedure with antibodies against human Ki-67 proliferation antigens revealed proliferating cells on cytospin preparations of coelomocytes extruded by electric shock. Quantification of proliferating cells in the suspension of extruded coelomocytes was performed by flow cytometry on FL-2 profiles of propidium iodide-stained samples; riboflavin-derived autofluorescence of eleocytes/chloragocytes was lost during detergent treatment. As expected, the percentage of coelomocytes proliferating in coelomic fluid was increased during restoration of coelomocyte number after experimental depletion. The method described here may be very useful for investigations of antigen-driven proliferation of earthworm coelomocytes. PMID:17544121

  16. Inhibition and recovery of biomarkers of earthworm Eisenia fetida after exposure to thiacloprid.

    PubMed

    Feng, Lei; Zhang, Lan; Zhang, Yanning; Zhang, Pei; Jiang, Hongyun

    2015-06-01

    Thiacloprid, a neonicotinoid insecticide, has been used widely in agriculture worldwide. In recent years, the adverse effects of neonicotinoid insecticides on non-target organisms have attracted more and more attention. In the present study, effects of thiacloprid on molecular biomarkers (GST, CarE, CAT, SOD, POD, and DNA damage) of earthworm Eisenia fetida were investigated using the artificial OECD soil for the first time. Earthworms were exposed to thiacloprid (1 and 3 mg/kg) for 7, 14, and 28 days and then transferred to the clean OECD soil for 35, 42, and 56 days. Results showed that activities of GST, CarE, CAT, SOD, and POD are inhibited following the exposure to thiacloprid at one or more sample times and then increased during the recovery course compared with the control. Significant DNA damage to E. fetida was also observed by olive tail moments in comet assay. These results suggested that thiacloprid could have harmful effect on earthworms, and these studied biomarkers might be used in the assessment of the risk of thiacloprid to the soil ecosystem environment. PMID:25613803

  17. Oxidative and genotoxic effects of 900 MHz electromagnetic fields in the earthworm Eisenia fetida.

    PubMed

    Tkalec, Mirta; Stambuk, Anamaria; Srut, Maja; Malari?, Krešimir; Klobu?ar, Göran I V

    2013-04-01

    Accumulating evidence suggests that exposure to radiofrequency electromagnetic field (RF-EMF) can have various biological effects. In this study the oxidative and genotoxic effects were investigated in earthworms Eisenia fetida exposed in vivo to RF-EMF at the mobile phone frequency (900 MHz). Earthworms were exposed to the homogeneous RF-EMF at field levels of 10, 23, 41 and 120 V m(-1) for a period of 2h using a Gigahertz Transversal Electromagnetic (GTEM) cell. At the field level of 23 V m(-1) the effect of longer exposure (4h) and field modulation (80% AM 1 kHz sinusoidal) was investigated as well. All exposure treatments induced significant genotoxic effect in earthworms coelomocytes detected by the Comet assay, demonstrating DNA damaging capacity of 900 MHz electromagnetic radiation. Field modulation additionally increased the genotoxic effect. Moreover, our results indicated the induction of antioxidant stress response in terms of enhanced catalase and glutathione reductase activity as a result of the RF-EMF exposure, and demonstrated the generation of lipid and protein oxidative damage. Antioxidant responses and the potential of RF-EMF to induce damage to lipids, proteins and DNA differed depending on the field level applied, modulation of the field and duration of E. fetida exposure to 900 MHz electromagnetic radiation. Nature of detected DNA lesions and oxidative stress as the mechanism of action for the induction of DNA damage are discussed. PMID:23352129

  18. Effects of stimulation intensity on sociopathic avoidance learning

    Microsoft Academic Search

    Frank A. Chesno; Peter R. Kilmann

    1975-01-01

    On the basis of scores on standardized tests (e.g., the Taylor Manifest Anxiety Scale), 90 public offenders were selected to represent low, medium, and high levels of anxiety and low and high levels of sociopathy. Ss were exposed to an avoidance situation under either low, medium, or high levels of background auditory stimulation. The avoidance task allowed shock to be

  19. Reward dominance and passive avoidance learning in adolescent psychopaths

    Microsoft Academic Search

    Angela Scerbo; Adrian Raine; Mary O'Brien; Cheryl-Jean Chan; Cathy Rhee; Norine Smiley

    1990-01-01

    This study tests predictions that adolescent psychopaths are hyperresponsive to rewards (Quay, 1988) and deficient in passive avoidance learning (Newman & Kosson, 1986). Forty male adolescent juvenile offenders were divided into psychopaths and nonpsychopaths using cluster analysis. Subjects were administered a passive avoidance learning task which required learning when to respond to cards associated with either reward or punishment. Results

  20. Cigarette tax avoidance and evasion.

    PubMed

    Stehr, Mark

    2005-03-01

    Variation in state cigarette taxes provides incentives for tax avoidance through smuggling, legal border crossing to low tax jurisdictions, or Internet purchasing. When taxes rise, tax paid sales of cigarettes will decline both because consumption will decrease and because tax avoidance will increase. The key innovation of this paper is to compare cigarette sales data to cigarette consumption data from the Behavioral Risk Factor Surveillance System (BRFSS). I show that after subtracting percent changes in consumption, residual percent changes in sales are associated with state cigarette tax changes implying the existence of tax avoidance. I estimate that the tax avoidance response to tax changes is at least twice the consumption response and that tax avoidance accounted for up to 9.6% of sales between 1985 and 2001. Because of the increase in tax avoidance, tax paid sales data understate the level of smoking and overstate the drop in smoking. I also find that the level of legal border crossing was very low relative to other forms of tax avoidance. If states have strong preferences for smoking control, they must pair high cigarette taxes with effective policies to curb smuggling and other forms of tax avoidance or employ alternative policies such as counter-advertising and smoking restrictions. PMID:15721046

  1. Impact of crop management factors in conservation tillage farming on earthworm density, age structure and species abundance in south-eastern Australia

    Microsoft Academic Search

    P. M Mele; M. R Carter

    1999-01-01

    Cropping practices commonly used in conservation tillage can potentially impact on earthworm abundance and distribution. Management practices associated with conservation tillage farming for cereals such as stubble retention and management, greater utilization of herbicides, and soil acidity amelioration were assessed for their influence on earthworm density, age structure, and species abundance at a total of seven sites on Chromic Luvisols

  2. Reduced density and nest survival of ground-nesting songbirds relative to earthworm invasions in northern hardwood forests.

    PubMed

    Loss, Scott R; Blair, Robert B

    2011-10-01

    European earthworms (Lumbricus spp.) are spreading into previously earthworm-free forests in the United States and Canada and causing substantial changes, including homogenization of soil structure, removal of the litter layer, and reduction in arthropod abundance and species richness of understory plants. Whether these changes affect songbirds that nest and forage on the forest floor is unknown. In stands with and without earthworms in the Chequamegon-Nicolet National Forest, Wisconsin (U.S.A.), we surveyed for, monitored nests of, and measured attributes of habitat of Ovenbirds (Seiurus aurocapillus) and Hermit Thrushes (Catharus guttatus), both ground-dwelling songbirds, and we sampled earthworms at survey points and nests. Bird surveys indicated significantly lower densities of Ovenbirds and Hermit Thrushes in relation to Lumbricus invasions at survey point and stand extents (3.1 and 15-20 ha, respectively). Modeling of Ovenbird nest survival (i.e., the probability that nestlings successfully fledge) indicated that lower survival probabilities were associated with increased sedge cover and decreased litter depth, factors that are related to Lumbricus invasions, possibly due to reduced nest concealment or arthropod abundance. Our findings provide compelling evidence that earthworm invasions may be associated with local declines of forest songbird populations. PMID:21797927

  3. Avoiding versus seeking: the relationship of information seeking to avoidance, blunting, coping, dissonance, and related concepts*

    PubMed Central

    Case, Donald O.; Andrews, James E.; Johnson, J. David; Allard, Suzanne L.

    2005-01-01

    Question: How have theorists and empirical researchers treated the human tendency to avoid discomforting information? Data Sources: A historical review (1890–2004) of theory literature in communication and information studies, coupled with searches of recent studies on uptake of genetic testing and on coping strategies of cancer patients, was performed. Study Selection: The authors' review of the recent literature included searches of the MEDLINE, PsychInfo, and CINAHL databases between 1992 and summer of 2004 and selective, manual searches of earlier literature. Search strategies included the following subject headings and key words: MeSH headings: Genetic Screening/psychology, Decision Making, Neoplasms/diagnosis/genetics/psychology; CINAHL headings: Genetic Screening, Genetic Counseling, Anxiety, Decision Making, Decision Making/Patient; additional key words: avoidance, worry, monitoring, blunting, cancer. The “Related Articles” function in MEDLINE was used to perform additional “citation pearl” searching. Main Results: The assumption that individuals actively seek information underlies much of psychological theory and communication practice, as well as most models of the information-seeking process. However, much research has also noted that sometimes people avoid information, if paying attention to it will cause mental discomfort or dissonance. Cancer information in general and genetic screening for cancer in particular are discussed as examples to illustrate this pattern. Conclusion: That some patients avoid knowledge of imminent disease makes avoidance behavior an important area for social and psychological research, particularly with regard to genetic testing. PMID:16059425

  4. Avoided crossings in driven systems

    SciTech Connect

    Holder, Benjamin P.; Reichl, Linda E. [Center for Studies in Statistical Mechanics and Complex Systems, University of Texas at Austin, Austin, Texas 78712 (United States)

    2005-10-15

    We characterize the avoided crossings in a two-parameter, time-periodic system which has been the basis for a wide variety of experiments. By studying these avoided crossings in the near-integrable regime, we are able to determine scaling laws for the dependence of their characteristic features on the nonintegrability parameter. As an application of these results, the influence of avoided crossings on dynamical tunneling is described and applied to the recent realization of multiple-state tunneling in an experimental system.

  5. Vertical jumping and signaled avoidance

    PubMed Central

    Cándido, Antonio; Maldonado, Antonio; Vila, Jaime

    1988-01-01

    This paper reports an experiment intended to demonstrate that the vertical jumping response can be learned using a signaled-avoidance technique. A photoelectric cell system was used to record the response. Twenty female rats, divided equally into two groups, were exposed to intertrial intervals of either 15 or 40 s. Subjects had to achieve three successive criteria of acquisition: 3, 5, and 10 consecutive avoidance responses. Results showed that both groups learned the avoidance response, requiring increasingly larger numbers of trials as the acquisition criteria increased. No significant effect of intertrial interval was observed. PMID:16812559

  6. Perspectives in avoidance-preference bioassays

    SciTech Connect

    Steele, C.W. [Edinboro Univ., PA (United States). Dept. of Biology and Health Services; Taylor, D.H.; Strickler-Shaw, S. [Miami Univ., Oxford, OH (United States). Dept. of Zoology

    1996-12-31

    Although behavioral endpoints are used in hazard assessment, establishment of water quality criteria and assessment of a contaminant`s hazard to aquatic life rely primarily on standard acute and chronic toxicity tests. Sublethal effects of pollutants should, however, be of major concern because more organisms experience sublethal rather than acutely or chronically lethal exposures of contaminants. The avoidance-preference approach to behavioral bioassays is very useful in screening pollutants for which the mechanisms of perception or response are largely unknown. The underlying philosophy of these studies is that an animal which perceives a chemical can be attracted or repulsed by it. No response is frequently assumed to indicate lack of perception. All three responses have broad ecological implications. The authors discuss the conditions required for performing avoidance-preference bioassays, as well as their sensitivities, advantages, and limitations. In this regard, a comparative approach is used in examining the results of avoidance-preference bioassays with zebrafish in two different apparatuses. Finally, they compare the results of avoidance-preference studies with other measures of the behavioral toxicity of lead to tadpoles.

  7. TOXICITY OF SELECTED ORGANIC CHEMICALS TO THE EARTHWORM 'EISENIA FETIDA'

    EPA Science Inventory

    A number of methods recently have been developed to biologically evaluate the impact of man's activities on soil ecosystems. Two test methods, the 2-d contact test and the 14-d artificial soil test, were used to evaluate the impact of six major classes of organic chemicals on the...

  8. Remediation of PAH-contaminated soil by the combination of tall fescue, arbuscular mycorrhizal fungus and epigeic earthworms.

    PubMed

    Lu, Yan-Fei; Lu, Mang

    2015-03-21

    A 120-day experiment was performed to investigate the effect of a multi-component bioremediation system consisting of tall fescue (Festuca arundinacea), arbuscular mycorrhizal fungus (AMF) (Glomus caledoniun L.), and epigeic earthworms (Eisenia foetida) for cleaning up polycyclic aromatic hydrocarbons (PAHs)-contaminated soil. Inoculation with AMF and/or earthworms increased plant yield and PAH accumulation in plants. However, PAH uptake by tall fescue accounted for a negligible portion of soil PAH removal. Mycorrhizal tall fescue significantly enhanced PAH dissipation, PAH degrader density and polyphenol oxidase activity in soil. The highest PAH dissipation (93.4%) was observed in the combination treatment: i.e., AMF+earthworms+tall fescue, in which the soil PAH concentration decreased from an initial value of 620 to 41 mg kg(-1) in 120 days. This concentration is below the threshold level required for Chinese soil PAH quality (45 mg kg(-1) dry weight) for residential use. PMID:25534968

  9. Encouragement Exchange: Avoiding Therapist Burnout.

    ERIC Educational Resources Information Center

    Evans, Timothy D.; Villavisanis, Robert

    1997-01-01

    States that therapists need to take care of their own mental health in order to avoid burnout. Discusses the encouragement exchange, a group setting where therapists help each other deal with stress. Provides a case example. (MKA)

  10. Avoiding character collisions in games 

    E-print Network

    Calderon, Manuel

    1999-01-01

    This thesis addresses an important current problem in the game industry, the problem of moving multiple characters along predefined paths in a two-dimensional plane while avoiding collisions between them. It demonstrates and describes a method...

  11. Automatic Multiagent Aircraft Collision Avoidance 

    E-print Network

    Sayahi, Shayan

    2014-09-22

    aircraft at any point during the flight, which proves to be a challenging task. This research seeks to find an optimized cooperative collision avoidance strategy to resolve conflicts in the horizontal and vertical planes by proposing maneuvers that involve...

  12. Medications Older Adults Should Avoid

    MedlinePLUS

    Medications Older Adults Should Avoid Tools and Tips Printer-friendly PDF Click here to see our other tip sheets. Because older adults often experience chronic health conditions that require treatment ...

  13. AN AUTOMATED DEVICE (AGARS) FOR STUDYING AVOIDANCE OF POLLUTANT GRADIENTS BY AQUATIC ORGANISMS

    EPA Science Inventory

    Most apparatus designed to detect avoidance of pollutants by aquatic organisms require visual observations of test organisms in steep pollutant gradients. GAARS (Aquatic Gradient Avoidance Response System) was developed to eliminate these limitations. This system allows animals t...

  14. Responses of growth inhibition and antioxidant gene expression in earthworms (Eisenia fetida) exposed to tetrabromobisphenol A, hexabromocyclododecane and decabromodiphenyl ether.

    PubMed

    Shi, Ya-Juan; Xu, Xiang-Bo; Zheng, Xiao-Qi; Lu, Yong-Long

    2015-01-01

    Tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and decabromodiphenyl ether (BDE 209), suspected ubiquitous contaminants, account for the largest volume of brominated flame retardants (BFRs) since penta-BDE and octa-BDE have been phased out globally. In this paper, the growth inhibition and gene transcript levels of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT)) and the stress-response gene involved in the prevention of oxidative stress (Hsp70) of earthworms (Eisenia fetida) exposed to TBBPA, HBCD and BDE 209 were measured to identify the toxicity effects of selected BFRs on earthworms. The growth of earthworms treated by TBBPA at 200 and 400mg/kg dw were inhibited at rate of 13.7% and 22.0% respectively, while there was no significant growth inhibition by HBCD and BDE 209. A significant (P<0.01) up-regulation of SOD expression level was observed in earthworms exposed to TBBPA at 50mg/kg dw (1.77-fold) and to HBCD at 400mg/kg dw (2.06-fold). The transcript level of Hsp70 gene was significantly up-regulated (P<0.01) when earthworms exposed to TBBPA at concentration of 50-200mg/kg (2.16-2.19-fold) and HBCD at 400mg/kg (2.61-fold). No significant variation of CAT gene expression in all the BFRs treatments was observed, neither does all the target gene expression level exposed to BDE 209. Assessed by growth inhibition and the changes at mRNA levels of encoding genes in earthworms, TBBPA showed the greatest toxicity, followed by HBCD and BDE 209, consistent with trends in molecular properties. The results help to understand the molecular mechanism of antioxidant defense. PMID:26117064

  15. Bioaccumulation of polycyclic aromatic hydrocarbons by earthworms: Assessment of equilibrium partitioning theory in in situ studies and water experiments

    SciTech Connect

    Ma, W.; Kleunen, A. van; Immerzeel, J. [Inst. for Forestry and Nature Research, Wageningen (Netherlands). Dept. of Ecotoxicology; Maagd, P.G.J. de [Inst. for Inland Water Management and Waste Water Treatment, Lelystad (Netherlands). Dept. of Industrial Pollution Control

    1998-09-01

    The purpose of this study was to assess the suitability of applying equilibrium partitioning (EqP) theory to predict the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) by earthworms when these are exposed to contaminated soils in the field. Studies carried out in situ in various contaminated floodplain sites showed the presence of linear relationships with intercept zero between the lipid-normalized concentration of different PAHs in the earthworm, Lumbricus rubellus and the organic-matter-normalized concentration of the compounds in soil. The demonstration of such an isometric relationship is in agreement with the prediction of EqP theory that the biota-soil accumulation factor (BSAF) should be independent of the octanol/water partition coefficient, log K{sub ow}. The average BSAF of PAH compounds in the sampled 20-cm top layer of soil was 0.10. The present study also investigated the route of uptake of PAHs for earthworms in soil. The bioconcentration factor of low-molecular-weight PAHs, such as phenanthrene, fluoranthene, and pyrene, was derived from bioconcentration kinetic modeling of water-only experiments and found to be of the same order of magnitude as the bioaccumulation factor in the field when the latter was normalized to calculated concentrations in soil pore water. The results indicated that the exposure of earthworms to PAHs in soil is mediated through direct contact of the worms with the dissolved interstitial soil-water phase, further supporting the applicability of EqP theory to PAHs. The experimental data on the biotransformation of PAHs suggest that earthworms possess some capacity of metabolization, although this does not seem to be a major factor in the total elimination of these compounds. Even though the EqP approach was found to be applicable to low-molecular-weight PAHs with respect to the prediction of bioaccumulation by earthworms in the field, the results were less conclusive for high-molecular-weight compounds, such as benzo[a]pyrene.

  16. Predator avoidance in extremophile fish.

    PubMed

    Bierbach, David; Schulte, Matthias; Herrmann, Nina; Zimmer, Claudia; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Riesch, Rüdiger; Plath, Martin

    2013-01-01

    Extreme habitats are often characterized by reduced predation pressures, thus representing refuges for the inhabiting species. The present study was designed to investigate predator avoidance of extremophile populations of Poecilia mexicana and P. sulphuraria that either live in hydrogen sulfide-rich (sulfidic) springs or cave habitats, both of which are known to have impoverished piscine predator regimes. Focal fishes that inhabited sulfidic springs showed slightly weaker avoidance reactions when presented with several naturally occurring predatory cichlids, but strongest differences to populations from non-sulfidic habitats were found in a decreased shoaling tendency with non-predatory swordtail (Xiphophorus hellerii) females. When comparing avoidance reactions between P. mexicana from a sulfidic cave (Cueva del Azufre) and the adjacent sulfidic surface creek (El Azufre), we found only slight differences in predator avoidance, but surface fish reacted much more strongly to the non-predatory cichlid Vieja bifasciata. Our third experiment was designed to disentangle learned from innate effects of predator recognition. We compared laboratory-reared (i.e., predator-naďve) and wild-caught (i.e., predator-experienced) individuals of P. mexicana from a non-sulfidic river and found no differences in their reaction towards the presented predators. Overall, our results indicate (1) that predator avoidance is still functional in extremophile Poecilia spp. and (2) that predator recognition and avoidance reactions have a strong genetic basis. PMID:25371337

  17. Predator Avoidance in Extremophile Fish

    PubMed Central

    Bierbach, David; Schulte, Matthias; Herrmann, Nina; Zimmer, Claudia; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Riesch, Rüdiger; Plath, Martin

    2013-01-01

    Extreme habitats are often characterized by reduced predation pressures, thus representing refuges for the inhabiting species. The present study was designed to investigate predator avoidance of extremophile populations of Poecilia mexicana and P. sulphuraria that either live in hydrogen sulfide-rich (sulfidic) springs or cave habitats, both of which are known to have impoverished piscine predator regimes. Focal fishes that inhabited sulfidic springs showed slightly weaker avoidance reactions when presented with several naturally occurring predatory cichlids, but strongest differences to populations from non-sulfidic habitats were found in a decreased shoaling tendency with non-predatory swordtail (Xiphophorus hellerii) females. When comparing avoidance reactions between P. mexicana from a sulfidic cave (Cueva del Azufre) and the adjacent sulfidic surface creek (El Azufre), we found only slight differences in predator avoidance, but surface fish reacted much more strongly to the non-predatory cichlid Vieja bifasciata. Our third experiment was designed to disentangle learned from innate effects of predator recognition. We compared laboratory-reared (i.e., predator-naďve) and wild-caught (i.e., predator-experienced) individuals of P. mexicana from a non-sulfidic river and found no differences in their reaction towards the presented predators. Overall, our results indicate (1) that predator avoidance is still functional in extremophile Poecilia spp. and (2) that predator recognition and avoidance reactions have a strong genetic basis. PMID:25371337

  18. A Standardized Soil Ecotoxicological Test Using Red Worms (Eisenia fetida).

    ERIC Educational Resources Information Center

    Paradise, Christopher J.

    2001-01-01

    Describes a simple, inexpensive test for soil contamination that can be used in a variety of courses to examine the effects of soil toxicity, to practice standardized laboratory procedures, to study experimental design and data analysis, or to investigate earthworm ecology. Presents background information along with details regarding equipment,…

  19. Multilevel ecotoxicity assessment of polycyclic musk in the earthworm Eisenia fetida using traditional and molecular endpoints.

    PubMed

    Chen, Chun; Xue, Shengguo; Zhou, Qixing; Xie, Xiujie

    2011-11-01

    The ecotoxicity assessment of galaxolide (HHCB) and tonalide (AHTN) was investigated in the earthworm Eisenia fetida using traditional and novel molecular endpoints. The median lethal concentration (LC(50)) for 7-day and 14-day exposures was 573.2 and 436.3 ?g g(-1) for AHTN, and 489.0 and 392.4 ?g g(-1) for HHCB, respectively. There was no observed significant effect on the growth rate of E. fetida after a 28-day exposure except that at the highest concentration (100 ?g g(-1)) of AHTN and HHCB, whereas a significant decrease of cocoon production was found in earthworms exposed to 50 and 100 ?g g(-1). To assess molecular-level effect, the expression of encoding antioxidant enzymes and stress protein genes were investigated upon sublethal exposures using the quantitative real time PCR assay. The expression level of SOD, CAT and calreticulin genes was up-regulated significantly, while the level of annetocin (ANN) and Hsp70 gene expression was down-regulated in E. fetida. Importantly, the level of ANN expression had a significant positive correlation with the reproduction rate of earthworms. Furthermore, the lowest observed effect concentration (LOECs) of ANN expression level was 3 ?g g(-1) for AHTN and 10 ?g g(-1) for HHCB, suggesting that ANN gene expression can serve as a more sensitive indicator of exposure to AHTN and HHCB than traditional endpoints such as cocoon production. The transcriptional responses of these genes may provide early warning molecular biomarkers for identifying contaminant exposure, and the data obtained from this study will contribute to better understand the toxicological effect of AHTN and HHCB. PMID:21789675

  20. The role of macrosymbiont genotypes and earthworms in the enrichment of soil with biological nitrogen

    NASA Astrophysics Data System (ADS)

    Nazaryuk, V. M.; Kalimullina, F. R.; Klenova, M. I.

    2010-06-01

    The specific features of the symbiotic apparatus and the accumulation of the plant biomass under the influence of different genotypes of peas ( Pisum sativum L.) on gray forest soils were studied in field conditions. With the alternation of legume and grass cultures, the genotypes of plants with supernodulation were found to affect the microbial nitrogen content in the soil to a greater extent than the concentration of ammonium and nitrate nitrogen. For the growing period, the N content in the microbial biomass increased, on the average, by 1.3 to 1.5 times. The consumption of nitrogen by the plants of the supernodular mutant K-301a was found to be 2.6 and 3.0 times greater than that by the pea plants of the Ramonskii-77 variety and of the K-562a line, respectively. During the after effect of the symbiotically bound air nitrogen, a significant uptake of this element was observed only by the oat plants grown after the K-56 2a. The nitrogen fixation by these plants was 1.3 times more active than that by the peas of the Ramonskii-77 variety. The importance of earthworms (Lumbricidae) and plant residues of different genotypes for the processes of mineralization of organic compounds and accumulation of ammonium, nitrate, and microbial nitrogen in the soils under optimal hydrothermal conditions was revealed. In the experiment, two maximums of the CO2 emission were recorded; they may be related to the periodic production of organic mass by the earthworms and the creation of favorable conditions for microbial activity by them. The accumulation of nitrate nitrogen (up to 150 mg/kg) in the soil was the greatest owing to the interaction between the earthworms and the residues of the supernodular K-301a mutant.

  1. Pilot-scale vermicomposting of pineapple wastes with earthworms native to Accra, Ghana.

    PubMed

    Mainoo, Nana O K; Barrington, Suzelle; Whalen, Joann K; Sampedro, Luis

    2009-12-01

    Pineapple wastes, an abundant organic waste in Accra, Ghana, were vermicomposted using native earthworms (Eudrilus eugeniae Kinberg) collected from the banks of streams and around bath houses of this city. Triplicate pilot-scale vermidigesters containing about 90 earthworms and three other control boxes with no earthworms were fed pineapple pulp or peels, and the loss of wet mass was monitored over 20 weeks. In a second experiment, a 1:1 mixture of pineapple peels and pulp (w/w) was fed to triplicate pilot-scale vermicomposters and control boxes during a 20 week period. One month after feeding ended, the vermicompost and composted (control) waste was air dried and analyzed. During the first experiment, the vermicomposted pineapple pulp and peels lost 99% and 87% of their wet mass, respectively, indicating the potential for vermicomposting. Fresh pineapple waste exhibited an initial pH of 4.4, but after 24 weeks, the vermicompost and compost had acquired a neutral to alkaline pH of 7.2-9.2. The vermicompost contained as much as 0.4% total N, 0.4% total P and 0.9% total K, and had a C:N ratio of 9-10. A reduction of 31-70% in the Escherichia coli plus Salmonella loads and 78-88% in the Aspergillus load was observed during vermicomposting. The rapid breakdown of pineapple wastes by E. eugeniae demonstrated the viability of vermicomposting as a simple and low cost technology recycling this waste into a soil amendment that could be used by the 2500 vegetable producers of Accra and its surrounding areas. PMID:19620003

  2. Seed dispersion by surface casting activities of earthworms in Colombian grasslands

    NASA Astrophysics Data System (ADS)

    Decaëns, Thibaud; Mariani, Lucero; Betancourt, Nixon; Jiménez, Juan José

    2003-09-01

    The effects of Martiodrilus sp. (Oligochaeta, Glossoscolecidae) on the soil seed banks was investigated in a Colombian savanna and two intensive pastures. Germination and washing-sieving methods were used to compare seed density, diversity, species composition and germination rates in earthworm casts and the surrounding soil. Although large amounts of seeds were present in casts (163.65, 156.84 and 60.36 seeds per 100 g of dry casts in the savanna, the old and young pastures, respectively), germination rates were 3-40 times lower than in the surrounding soil, likely due to degradation during the gut transit. The number of viable seeds present in casts was 0.40, 7.46 and 1.99 seeds per 100 g of dry casts in the savanna, the old and young pastures, respectively. Species composition of viable seeds was quite different in casts compared to soil, probably because of selective seed ingestion by earthworms. Viable seeds deposited in surface casts each year represented 0.65%, 16.17% and 8.24% of the total viable seed bank of the soil, in the savanna, the old and young pastures, respectively. In the savanna and the old pasture, species composition in casts was more similar to the vegetation than species composition in the soil was. This may indicate that ingested seeds that survive gut transit have a greater chance to germinate than those of the soil seed bank, providing vegetation cover is sufficiently opened to enable germination processes. Thus, casts may be considered as a regeneration niche for plant species, and earthworm activity a factor that enhances, in some cases, the expression of the soil seed bank in the standing vegetation.

  3. Identification and Optimization of Classifier Genes from Multi-Class Earthworm Microarray Dataset

    PubMed Central

    Li, Ying; Wang, Nan; Perkins, Edward J.; Zhang, Chaoyang; Gong, Ping

    2010-01-01

    Monitoring, assessment and prediction of environmental risks that chemicals pose demand rapid and accurate diagnostic assays. A variety of toxicological effects have been associated with explosive compounds TNT and RDX. One important goal of microarray experiments is to discover novel biomarkers for toxicity evaluation. We have developed an earthworm microarray containing 15,208 unique oligo probes and have used it to profile gene expression in 248 earthworms exposed to TNT, RDX or neither. We assembled a new machine learning pipeline consisting of several well-established feature filtering/selection and classification techniques to analyze the 248-array dataset in order to construct classifier models that can separate earthworm samples into three groups: control, TNT-treated, and RDX-treated. First, a total of 869 genes differentially expressed in response to TNT or RDX exposure were identified using a univariate statistical algorithm of class comparison. Then, decision tree-based algorithms were applied to select a subset of 354 classifier genes, which were ranked by their overall weight of significance. A multiclass support vector machine (MC-SVM) method and an unsupervised K-mean clustering method were applied to independently refine the classifier, producing a smaller subset of 39 and 30 classifier genes, separately, with 11 common genes being potential biomarkers. The combined 58 genes were considered the refined subset and used to build MC-SVM and clustering models with classification accuracy of 83.5% and 56.9%, respectively. This study demonstrates that the machine learning approach can be used to identify and optimize a small subset of classifier/biomarker genes from high dimensional datasets and generate classification models of acceptable precision for multiple classes. PMID:21060837

  4. Subcellular compartmentalization of lead in the earthworm, Eisenia fetida: Relationship to survival and reproduction.

    PubMed

    Jones, Robert P; Bednar, Anthony J; Inouye, Laura S

    2009-05-01

    Metals are detoxified and sequestered into subcellular compartments when accumulated by earthworms. Differential centrifugation was used to quantify subcellular Pb in three separate studies to measure 14-day acute toxicity (lethality), 28/56-day reproductive effects, and 90-day bioaccumulation in spiked-soil exposed earthworms, Eisenia fetida. Observed toxicity and total body Pb was consistent with published work of others. Pb showed concentration-dependent toxicity relationships (lethality and reproduction) for total and subcellular Pb. Toxic fraction and total Pb showed similar concentration-response patterns in the 14-day and 28/56-day studies and tended to increase towards a plateau at higher concentrations. Linear correlations of subcellular to total Pb was observed in all studies except the 90-day bioaccumulation study in which toxic fraction Pb appeared to approach a maximum over the period between Day 56 and Day 90. In a follow-on study using two different contaminated soil types, toxic fraction and total Pb concentrations as related to reproductive effects were consistent with data from our spiked soil studies, and this suggests it may be possible to use such values to "factor out" matrix-specific influences that otherwise skew toxicity values when expressed relative to soil concentrations. Our findings, however, suggest the subcellular fractionation approach may not offer advantages over total Pb determination in short-term exposure studies but may become important when longer exposure periods (greater than 90 days) are considered. In this respect, the technique we describe has the potential to provide valuable information for assessing and interpreting Pb toxicity as a function of earthworm body burden. PMID:19193437

  5. Toxic Effect of Cadmium Assay in Contaminated Soil Earthworm Cell Using Modified Sensor

    PubMed Central

    Kyung, Lee; Kim, Chae Hwa; Seo, Roma; Lee, Soo Youn; Kim, Lina; Chae, Su min; Choi, Sung Wook; Kim, Ji Yoon

    2015-01-01

    A voltammetric toxic metal of cadmium detection was studied using a fluorine doped graphite pencil electrode (FPE) in a seawater electrolyte. In this study, square wave (SW) stripping and chronoamerometry were used for determination of Cd(II) in seawater. Affordable pencils and an auxiliary electrode were used as reference. All experiments in this study could be performed at reasonable cost by using graphite pencil. The application was performed on the tissue of contaminated soil earthworm. The results show that the method can be applicable for vegetables and in vivo fluid or medicinal diagnosis.

  6. Toxic effects of benomyl on the ultrastructure during spermatogenesis of the earthworm Eisenia fetida.

    PubMed

    Sorour, J; Larink, O

    2001-11-01

    The present study has investigated the toxic effect of benomyl on the ultrastructure of the male reproductive system and spermatozoa of the earthworm Eiseniafetida in a laboratory experiment. Three different concentrations of benomyl (8.3, 56, 112 mg/kg dry soil) were applied for one week. These applications caused abnormalities in ultrastructure of the cytophore, the spermatogonia, spermatids, and spermatozoa. The alterations include uncomplete forms of acrosomes, nuclear distortion, and disruption of microtubules. These micromorphological changes should be included in a model for predicting environmental hazards. PMID:11915954

  7. Impact of roots, mycorrhizas and earthworms on soil physical properties as assessed by shrinkage analysis

    NASA Astrophysics Data System (ADS)

    Milleret, R.; Le Bayon, R.-C.; Lamy, F.; Gobat, J.-M.; Boivin, P.

    2009-07-01

    SummarySoil biota such as earthworms, arbuscular mycorrhizal fungi (AMF) and plant roots are known to play a major role in engineering the belowground part of the terrestrial ecosystems, thus strongly influencing the water budget and quality on earth. However, the effect of soil organisms and their interactions on the numerous soil physical properties to be considered are still poorly understood. Shrinkage analysis allows quantifying a large spectrum of soil properties in a single experiment, with small standard errors. The objectives of the present study were, therefore, to assess the ability of the method to quantify changes in soil properties as induced by single or combined effects of leek roots ( Allium porrum), AMF ( Glomus intraradices) and earthworms ( Allolobophora chlorotica). The study was performed on homogenised soil microcosms and the experiments lasted 35 weeks. The volume of the root network and the external fungal hyphae was measured at the end, and undisturbed soil cores were collected. Shrinkage analysis allowed calculating the changes in soil hydro-structural stability, soil plasma and structural pore volumes, soil bulk density and plant available water, and structural pore size distributions. Data analysis revealed different impacts of the experimented soil biota on the soil physical properties. At any water content, the presence of A. chlorotica resulted in a decrease of the specific bulk volume and the hydro-structural stability around 25%, and in a significant increase in the bulk soil density. These changes went with a decrease of the structural pore volumes at any pore size, a disappearing of the thinnest structural pores, a decrease in plant available water, and a hardening of the plasma. On the contrary, leek roots decreased the bulk soil density up to 1.23 g cm -3 despite an initial bulk density of 1.15 g cm -3. This increase in volume was accompanied with a enhanced hydro-structural stability, a larger structural pore volume at any pore size, smaller structural pore radii and an increase in plant available water. Interestingly, a synergistic effect of leek roots and AMF in the absence of the earthworms was highlighted, and this synergistic effect was not observed in presence of earthworms. The structural pore volume generated by root and AMF growth was several orders of magnitude larger than the volume of the organisms. Root exudates as well as other AMF secretion have served as carbon source for bacteria that in turn would enhance soil aggregation and porosity, thus supporting the idea of a self-organization of the soil-plant-microbe complex previously described.

  8. Avoided cost standard under PURPA

    SciTech Connect

    Cole, R.J.; Holmlund, I.; Smith, S.A.; Williams, T.A.

    1983-04-01

    The Public Utility Regulatory Policies Act (PURPA) (P.L. 95-617) was passed to encourage electricity conservation through a variety of regulatory and rate reforms. Information is provided on the controversy surrounding the avoided cost standard established under PURPA. Promulgated by the Federal Energy Regulatory Committee (FERC) in February 1980, the avoided cost standard sets a minimum rate for utilities purchasing power from a qualified facility (QF) at the utilities full avoided cost. Recent court cases have challenged this standard and FERC is currently appealing to the Supreme Court. The impact of these court cases may have little effect on the actual rates set by state Public Utility Commissions (PUCs), which can require rates higher than the minimums established by FERC, since many PUCs appear in favor of requiring full avoided costs. The arguments for and against requiring utilities to pay full avoided costs come down to balancing between incentives for QFs on the one hand and fairness to utilities and their non-QF customers on the other.

  9. 47 CFR 74.604 - Interference avoidance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Interference avoidance. 74.604 Section 74...Broadcast Auxiliary Stations § 74.604 Interference avoidance. (a) [Reserved] ...as may be necessary to avoid mutual interference, including consultation...

  10. 47 CFR 74.604 - Interference avoidance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Interference avoidance. 74.604 Section 74...Broadcast Auxiliary Stations § 74.604 Interference avoidance. (a) [Reserved] ...as may be necessary to avoid mutual interference, including consultation...

  11. 47 CFR 74.604 - Interference avoidance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Interference avoidance. 74.604 Section 74...Broadcast Auxiliary Stations § 74.604 Interference avoidance. (a) [Reserved] ...as may be necessary to avoid mutual interference, including consultation...

  12. 47 CFR 74.604 - Interference avoidance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Interference avoidance. 74.604 Section 74...Broadcast Auxiliary Stations § 74.604 Interference avoidance. (a) [Reserved] ...as may be necessary to avoid mutual interference, including consultation...

  13. 47 CFR 74.604 - Interference avoidance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Interference avoidance. 74.604 Section 74...Broadcast Auxiliary Stations § 74.604 Interference avoidance. (a) [Reserved] ...as may be necessary to avoid mutual interference, including consultation...

  14. Avoiding Lexical Ambiguities: Does Prior Experience Help? 

    E-print Network

    Burns, Rebecca

    2008-06-27

    This study examined whether speakers avoid lexical ambiguities in a communication task by avoiding ambiguous descriptions when two interpretations are plausible and, furthermore, whether this avoidance is increased after ...

  15. Traffic jam driving with NMV avoidance

    NASA Astrophysics Data System (ADS)

    Milanés, Vicente; Alonso, Luciano; Villagrá, Jorge; Godoy, Jorge; de Pedro, Teresa; Oria, Juan P.

    2012-08-01

    In recent years, the development of advanced driver assistance systems (ADAS) - mainly based on lidar and cameras - has considerably improved the safety of driving in urban environments. These systems provide warning signals for the driver in the case that any unexpected traffic circumstance is detected. The next step is to develop systems capable not only of warning the driver but also of taking over control of the car to avoid a potential collision. In the present communication, a system capable of autonomously avoiding collisions in traffic jam situations is presented. First, a perception system was developed for urban situations—in which not only vehicles have to be considered, but also pedestrians and other non-motor-vehicles (NMV). It comprises a differential global positioning system (DGPS) and wireless communication for vehicle detection, and an ultrasound sensor for NMV detection. Then, the vehicle's actuators - brake and throttle pedals - were modified to permit autonomous control. Finally, a fuzzy logic controller was implemented capable of analyzing the information provided by the perception system and of sending control commands to the vehicle's actuators so as to avoid accidents. The feasibility of the integrated system was tested by mounting it in a commercial vehicle, with the results being encouraging.

  16. Method for detecting and avoiding flight hazards

    NASA Astrophysics Data System (ADS)

    von Viebahn, Harro; Schiefele, Jens

    1997-06-01

    Today's aircraft equipment comprise several independent warning and hazard avoidance systems like GPWS, TCAS or weather radar. It is the pilot's task to monitor all these systems and take the appropriate action in case of an emerging hazardous situation. The developed method for detecting and avoiding flight hazards combines all potential external threats for an aircraft into a single system. It is based on an aircraft surrounding airspace model consisting of discrete volume elements. For each element of the volume the threat probability is derived or computed from sensor output, databases, or information provided via datalink. The position of the own aircraft is predicted by utilizing a probability distribution. This approach ensures that all potential positions of the aircraft within the near future are considered while weighting the most likely flight path. A conflict detection algorithm initiates an alarm in case the threat probability exceeds a threshold. An escape manoeuvre is generated taking into account all potential hazards in the vicinity, not only the one which caused the alarm. The pilot gets a visual information about the type, the locating, and severeness o the threat. The algorithm was implemented and tested in a flight simulator environment. The current version comprises traffic, terrain and obstacle hazards avoidance functions. Its general formulation allows an easy integration of e.g. weather information or airspace restrictions.

  17. Response of earthworm communities to soil disturbance: Fractal dimension of soil and species’ rank-abundance curves

    Microsoft Academic Search

    Andrés Duhour; Cristina Costa; Fernando Momo; Liliana Falco; Leonardo Malacalza

    2009-01-01

    Soil structure degradation and its relationship with soil fauna communities is a crucial issue in soil management. The aim of this work is to analyze soil fractal dimensions and the earthworm community structure along a perturbation gradient in a Typic Argiudoll soil with different combinations of annual crops and pastures. Samples were taken in four sites: a natural grassland (NAT)

  18. The Effect of Biochar and Its Interaction with the Earthworm Pontoscolex corethrurus on Soil Microbial Community Structure in Tropical Soils

    PubMed Central

    Paz-Ferreiro, Jorge; Liang, Chenfei; Fu, Shenglei; Mendez, Ana; Gasco, Gabriel

    2015-01-01

    Biochar effects on soil microbial abundance and community structure are keys for understanding the biogeochemical cycling of nutrients and organic matter turnover, but are poorly understood, in particular in tropical areas. We conducted a greenhouse experiment in which we added biochars produced from four different feedstocks [sewage sludge (B1), deinking sewage sludge (B2), Miscanthus (B3) and pine wood (B4)] at a rate of 3% (w/w) to two tropical soils (an Acrisol and a Ferralsol) planted with proso millet (Panicum milliaceum L.). The interactive effect of the addition of earthworms was also addressed. For this purpose we utilized soil samples from pots with or without the earthworm Pontoscolex corethrurus, which is a ubiquitous earthworm in tropical soils. Phospholipid fatty acid (PLFA) measurements showed that biochar type, soil type and the presence of earthworms significantly affected soil microbial community size and structure. In general, biochar addition affected fungal but not bacterial populations. Overall, biochars rich in ash (B1 and B2) resulted in a marked increase in the fungi to bacteria ratio, while this ratio was unaltered after addition of biochars with a high fixed carbon content (B3 and B4). Our study remarked the contrasting effect that both, biochar prepared from different materials and macrofauna, can have on soil microbial community. Such changes might end up with ecosystem-level effects. PMID:25898344

  19. Effects of Low Levels of Lead on Growth and Reproduction of the Asian Earthworm Perionyx excavatus (Oligochaeta)

    Microsoft Academic Search

    M. S. Maboeta; A. J. Reinecke; S. A. Reinecke

    1999-01-01

    The effects of sublethal concentrations of lead nitrate on growth and reproduction of the Asian composting earthworm species Perionyx excavatus was studied experimentally by exposing worms in an organic substrate to lead nitrate-contaminated food over a period of 76 days. The results revealed that growth was affected negatively by the presence of lead while maturation rate and cocoon production was

  20. Vermicomposting of coffee pulp using the earthworm Eisenia fetida : Effects on C and N contents and the availability of nutrients

    Microsoft Academic Search

    F. H. Orozco; J. Cegarra; L. M. Trujillo; A. Roig

    1996-01-01

    In Colombia, more than 1 million tons of coffee pulp are produced every year. Its transformation into compost by means of turned piles has led to a final product with poor physical and chemical characteristics and vermicomposting has been suggested as an alternative method of transforming these wastes into a useful organic fertilizer. The ability of the earthworm Eisenia fetida

  1. Tolerance to Zinc in Populations of the Earthworm Lumbricus rubellus from Uncontaminated and Metal-Contaminated Ecosystems

    E-print Network

    Hopkin, Steve

    Tolerance to Zinc in Populations of the Earthworm Lumbricus rubellus from Uncontaminated and Metal. Zinc tolerance in Lumbricus rubellus populations from two metal-polluted (smelter and mine) sites was studied by comparing the effects of zinc with responses in a reference site strain. For the study, adult

  2. Effect of triclosan on reproduction, DNA damage and heat shock protein gene expression of the earthworm Eisenia fetida.

    PubMed

    Lin, Dasong; Li, Ye; Zhou, Qixing; Xu, Yingming; Wang, Di

    2014-12-01

    Triclosan (TCS) is released into the terrestrial environment via the application of sewage sludge and reclaimed water to agricultural land. More attention has been paid to its effect on non-target soil organisms. In the present study, chronic toxic effects of TCS on earthworms at a wide range of concentrations were investigated. The reproduction, DNA damage, and expression levels of heat shock protein (Hsp70) gene of earthworms were studied as toxicity endpoints. The results showed that the reproduction of earthworms were significantly reduced (p < 0.05) after exposure to the concentrations ranges from 50 to 300 mg kg(-1), with a half-maximal effective concentration (EC50) of 142.11 mg kg(-1). DNA damage, detected by the comet assay, was observed and there was a clear significant (R(2) = 0.941) relationship between TCS concentrations and DNA damage, with the EC50 value of 8.85 mg kg(-1). The expression levels of Hsp70 gene of earthworms were found to be up-regulated under the experimental conditions. The expression level of hsp70 gene increased, up to about 2.28 folds that in the control at 50 mg kg(-1). The EC50 value based on the Hsp70 biomarker was 1.79 mg kg(-1). Thus, among the three toxicity endpoints, the Hsp70 gene was more sensitive to TCS in soil. PMID:25134678

  3. Genotoxic endpoints in the earthworms sub-lethal assay to evaluate natural soils contaminated by metals and radionuclides.

    PubMed

    Lourenço, Joana I; Pereira, Ruth O; Silva, Ana C; Morgado, José M; Carvalho, Fernando P; Oliveira, Joăo M; Malta, Margarida P; Paiva, Artur A; Mendo, Sónia A; Gonçalves, Fernando J

    2011-02-15

    Eisenia andrei was exposed, for 56 days, to a contaminated soil from an abandoned uranium mine and to the natural reference soil LUFA 2.2. The organisms were sampled after 0, 1, 2, 7, 14 and 56 days of exposure, to assess metals bioaccumulation, coelomocytes DNA integrity and cytotoxicity. Radionuclides bioaccumulation and growth were also determined at 0 h, 14 and 56 days of exposure. Results have shown the bioaccumulation of metals and radionuclides, as well as, growth reduction, DNA damages and cytotoxicity in earthworms exposed to contaminated soil. The usefulness of the comet assay and flow cytometry, to evaluate the toxicity of contaminants such as metals and radionuclides in earthworms are herein reported. We also demonstrated that DNA strand breakage and immune cells frequency are important endpoints to be employed in the earthworm reproduction assay, for the evaluation of soil geno and cytotoxicity, as part of the risk assessment of contaminated areas. This is the first study that integrates DNA damage and cytotoxicity evaluation, growth and bioaccumulation of metals and radionuclides in a sub lethal assay, for earthworms exposed to soil contaminated with metals and radionuclides. PMID:21146299

  4. Sublethal toxicity of the antiparasitic abamectin on earthworms and the application of neutral red retention time as a biomarker

    Microsoft Academic Search

    John Jensen; Xiaoping Diao; Janeck J. Scott-fordsmand

    2007-01-01

    The antiparasitic abamectin has been proven effective against both endo- and ectoparasites of farm animals and hence used widely in animal husbandry. It may enter the soil environment with the excreta of treated animals. Very little information is available with regard to the sub-lethal effects of abamectin on soil invertebrates, such as earthworms. The objective of this study was to

  5. Distribution of aged atrazine related 14C-residues in natural soil following incubation with the earthworm Apporectodea caliginosa

    NASA Astrophysics Data System (ADS)

    Andreou, Kostas; Semple, Kirk; Jones, Kevin

    2010-05-01

    The distribution and localisation of atrazine related 14C-residues into the different physical fractions of soil may reveal information on processes taking place in soil. Soils amended with 14C-atrazine, were aged for 22 years under environmental conditions in a lysimeter in Germany. The soil was sampled and subjected to physical and chemical fractionation before and after incubation for 7 days with the earthworm Apporectodea caliginosa. No significant change in the soil physical and chemical fractionation of the atrazine related 14C-residues and organic carbon was observed in this study due to the activity of the A. caliginosa. The smaller size soil fractions (Microaggregates and Colloids) were highly enriched with aged atrazine 14C-residues equivalents and organic carbon. Also the humic acid extracted using a simple alkaline extraction have were also enriched with aged atrazine 14C-residues equivalents. The low organic carbon content of the soil, the absence of relatively fresh organic matter and the long ageing time might explain the limited bioavailability of the atrazine related 14C-residues to the earthworm. This finding is of particular importance given that the soil used here was aged under natural environmental conditions compared to laboratory studies. Earthworms are important species in soil ecology and thus, the question of the bioavailability of aged pesticide residues to such organism is critical. The bioavalability of the atrazine 14C-residues equivalent was absent in the current study illustrating that those aged residues posed minimal risk to earthworms.

  6. The mechanics and energetics of soil bioturbation by earthworms and plant roots - Impacts on soil structure generation and maintenance

    NASA Astrophysics Data System (ADS)

    Or, Dani; Ruiz, Siul; Schymanski, Stanlislaus

    2015-04-01

    Soil structure is the delicate arrangement of solids and voids that facilitate numerous hydrological and ecological soil functions ranging from water infiltration and retention to gaseous exchange and mechanical anchoring of plant roots. Many anthropogenic activities affect soil structure, e.g. via tillage and compaction, and by promotion or suppression of biological activity and soil carbon pools. Soil biological activity is critical to the generation and maintenance of favorable soil structure, primarily through bioturbation by earthworms and root proliferation. The study aims to quantify the mechanisms, rates, and energetics associated with soil bioturbation, using a new biomechanical model to estimate stresses required to penetrate and expand a cylindrical cavity in a soil under different hydration and mechanical conditions. The stresses and soil displacement involved are placed in their ecological context (typical sizes, population densities, burrowing rates and behavior) enabling estimation of mechanical energy requirements and impacts on soil organic carbon pool (in the case of earthworms). We consider steady state plastic cavity expansion to determine burrowing pressures of earthworms and plant roots, akin to models of cone penetration representing initial burrowing into soil volumes. Results show that with increasing water content the strain energy decreases and suggest trade-offs between cavity expansion pressures and energy investment for different root and earthworm geometries and soil hydration. The study provides a quantitative framework for estimating energy costs of bioturbation in terms of soil organic carbon or the mechanical costs of soil exploration by plant roots as well as mechanical and hydration limits to such activities.

  7. A comparative study of synchronous treatment of sewage and sludge by two vermifiltrations using an epigeic earthworm Eisenia fetida.

    PubMed

    Xing, Meiyan; JianYang; Wang, Yayi; Liu, Jing; Yu, Fen

    2011-01-30

    Reduction and stabilization of sewage sludge during the clarification of municipal wastewater was synchronously shown to be improved significantly in a pilot-scale vermifiltration using an epigeic earthworm Eisenia fetida. The present study aimed to select a better filter media suited to vermifiltration performance by the comparisons of sludge yields, the characteristics of the by-products of vermifiltration-vermicast and the abrasions of earthworms between ceramsite and quartz sand. It was observed that the sludge yield of the CVB (Ceramsite Vermibed) ranged from 0.07 to 0.09 kg SS/kg COD(removed) at ambient temperature of 4-29 °C, representing 81% and 50% lower than that of the SVB (Quartz Sand Vermibed) and other reduction systems mentioned in this study. In addition, the sludge morphology variations described that the vermicast sludge from the CVB was more completely digested by earthworm than that of the SVB. The abrasions of the body wall of the earthworms in the CVB depicted less injured than that of in the SVB. So the ceramsite as filter media was better suited for the vermifiltration than the quartz sand. PMID:21041027

  8. Collision avoidance for general aviation

    Microsoft Academic Search

    Thomas Billingsley; Mykel Kochenderfer; James Chryssanthacopoulos

    2011-01-01

    • Approach based on Markov decision process used to optimize collision avoidance logic for GA • Compared current TCAS and Descend\\/Climb responsive coordination with GA optimized logic — Optimized logic safer than TCAS and D\\/C against non-GA and GA intruder aircraft — Performance against GA intruders also resulted in lower Pr(NMAC) • Probability of alert and reversal with optimized logic

  9. Collision Avoidance Betueen Mobile Robots

    Microsoft Academic Search

    M. Saito; T. Tsumura

    1989-01-01

    This paper presents a local approach to real-time collision avoidance between mobile robots based on velocity vector modification method. In the approach, a risk evaluation function of neighbouring two mobile robots is introduced to detect their potential collision and to lead the velocity modification method. Simulation results show the validity of this method. In this paper, a local approach to

  10. Visual navigation with obstacle avoidance

    Microsoft Academic Search

    Andrea Cherubini; Francois Chaumette

    2011-01-01

    We present and validate a framework for vi- sual navigation with obstacle avoidance. The approach was originally designed in (1), but major improvements and real outdoor experiments are added here. Visual navigation consists of following a path, represented as an ordered set of key images, that have been acquired in a preliminary teaching phase. While following such path, the robot

  11. Visual navigation with obstacle avoidance

    Microsoft Academic Search

    Andrea Cherubini; Francois Chaumette

    2011-01-01

    We present and validate a framework for visual navigation with obstacle avoidance. The approach was originally designed in [1], but major improvements and real outdoor experiments are added here. Visual navigation consists of following a path, represented as an ordered set of key images, that have been acquired in a preliminary teaching phase. While following such path, the robot is

  12. OBSTACLE AVOIDANCE IN LOCAL NAVIGATION

    Microsoft Academic Search

    Daniel Castro; Urbano Nunes; António Ruano

    2002-01-01

    A reactive navigation system for an autonomous non-holonomic mobile robot in dynamic environments is presented. A new object detection algorithm and a new reactive collision avoidance method are presented. The sensory perception is based in a laser range finder (LRF) system. Simulation results are presented to verify the effectiveness of the proposed local navigational system in unknown environments with multiple

  13. Avoiding unfavourable outcomes in liposuction

    PubMed Central

    Khanna, Atul; Filobbos, George

    2013-01-01

    The origin of liposuction can be traced to an adverse event by Dujarrier in 1921 when he used a uterine curette to remove fat from the knees of a ballerina ending in an amputation secondary to damage of the femoral artery. The history of liposuction since then has been one of avoiding complications and optimising outcome. After this adverse event, liposuction was abandoned until the 1960's when Schrudde revived the practice using small stab incisions and sharp curettage with the secondary suction to aspirate the freed tissue. This technique was associated with a high incidence of complications especially seroma and skin necrosis. Illouz then replaced the curette with a blunt cannula connected to vacuum pump thus avoiding the complications of a sharp curette. Despite the presence of various techniques for liposuction, suction assisted liposuction (SAL) is still the standard technique of liposuction. This article aims to discuss literature regarding the various aspects of liposuction (SAL) and to highlight the salient points in the literature and in the senior author's experience in order to avoid unfavourable outcomes in liposuction. A literature review on avoiding complication is in liposuction including some of the seminal papers on liposuction. Liposuction is generally a safe procedure with reproducible outcome. Just like any surgical procedure it should be treated with the utmost care. Illouz published 10 commandments for liposuction in 1989 and we review these commandments to demonstrate how liposuction has evolved. PMID:24501475

  14. Application of Synchrotron Methods to Assess the Uptake of Roadway-Derived Zn by Earthworms in an Urban Soil

    SciTech Connect

    Lev,S.; Landa, E.; Szlavecz, K.; Casey, R.; Snodgrass, J.

    2008-01-01

    The impact of human activities on biogeochemical cycles in terrestrial environments is nowhere more apparent than in urban landscapes. Trace metals, collected on roadways and transported by storm water, may contaminate soils and sediments associated with storm water management systems. These systems will accumulate metals and associated sediments may reach toxic levels for terrestrial and aquatic organisms using the retention basins as habitat. The fate and bioavailability of these metals once deposited is poorly understood. Here we present results from a dose-response experiment that examines the application of synchrotron X-ray fluorescence methods ({mu}-SXRF) to test the hypothesis that earthworms will bio-accumulate Zn in a roadway-dust contaminated soil system providing a potential pathway for roadway contaminants into the terrestrial food web, and that the storage and distribution of Zn will change with the level of exposure reflecting the micronutrient status of Zn. Lumbricus friendi was exposed to Zn-bearing roadway dust amended to a field soil at six target concentrations ranging from background levels (45 mg/kg Zn) to highly contaminated levels (460 mg/kg Zn) designed to replicate the observed concentration range in storm-water retention basin soils. After a 30 day exposure, Zn storage in the intestine is positively correlated with dose and there is a change in the pattern of Zn storage within the intestine. This relationship is only clear when {mu}-SXRF Zn map data is coupled with a traditional toxicological approach, and suggests that the gut concentration in L. friendi is a better indicator of Zn bioaccumulation and storage than the total body burden.

  15. Influence of invasive earthworm activity on carbon dynamics in soils from the Aspen Free Air CO2 Enrichment Experiment

    NASA Astrophysics Data System (ADS)

    Filley, T. R.; Top, S. M.; Hopkins, F. M.

    2010-12-01

    The influence of CO2-driven increase in net primary productivity on soil organic carbon accrual has received considerable emphasis in ecological literature with conclusions varying from positive, to neutral, to negative. What has been understudied is the coupled role of soil fauna, such as earthworms, in controlling the ultimate fate of new above and below ground plant carbon under elevated CO2. Such considerations are particularly relevant considering that in most northern North American forests earthworms are an exotic organism known to cause significant changes to forest floor chemistry and soil structure, possibly increasing nutrient loss from both soil and leaf litter and mixing litter and humus deep into the mineral soil. The impact of these exotic earthworms on overall soil carbon stabilization is largely unknown but likely a function of both species composition and edaphic soil properties. In this paper we present the initial results of a carbon isotope study (13C, 14C) conducted at the Aspen free air CO2 enrichment (FACE) site, Rhinelander, WI, USA to track allocation and redistribution within the soil of plant litter and root carbon (bulk and biopolymer). Along with litter and soil to 25 cm depth, earthworm populations were quantified, and their gut contents collected for isotopic and plant biopolymer chemistry analysis. Contributions of root vs. leaf input to soil and earthworm fecal matter were derived from differences in the chemical and isotope composition of alkaline CuO-derived lignin and substituted fatty acids (SFA) from cutin and suberin. Our investigation demonstrates the presence of invasive European earthworms, of both litter and surface soil dwelling (epigeic) and deep soil dwelling (endogeic) varieties, whose abundance increases under elevated CO2 conditions. Additionally, the different species show selective vertical movement of new and pre-FACE plant biopolymers indicating dynamics in root and leaf decomposition and burial (down to 30 cm) based upon exotic earthworm activity. The isotopic analysis also demonstrates that these invasive ecosystem engineers are bringing up “old” pre-FACE carbon to the surface, diluting the surface soil carbon isotope signature and potentially causing an apparent “slowing” of the rate of accumulation of FACE derived carbon. Our results highlight the complexity of determining soil C dynamics and the important role of invertebrate ecology in this process.

  16. Microbial diversity and digestive enzyme activities in the gut of earthworms found in sawmill industries in Abeokuta, Nigeria.

    PubMed

    Bamidele, Julius A; Idowu, Adewunmi B; Ademolu, Kehinde O; Atayese, Adijat O

    2014-09-01

    The growing demand for wood has resulted in large volumes of wood wastes that are daily released to the soil from the activities of sawmills in South-Western Nigeria. In an attempt to setup a bioremediation model for sawdust, this study therefore aimed at evaluating microbial diversity, and the level of digestive enzymes in the gut of earthworms (Eudrilus eugeniae, Libyodrilus violaceous and Hyperiodrilus africanus) of sawmill origin. Four major sawmills located in Abeokuta (7°9'12" N- 3°19'35" E), namely Lafenwa, Sapon, Isale-Ake and Kotopo sawmills were used for this study. The arboretum of the Federal University of Agriculture, Abeokuta was used as control. Gut microbial analysis was carried out using the pour-plate method while digestive enzyme activities in the earthworm guts were done by the spectrophotometric method. Higher microbial counts (28.5 ± 0.1 x 10(3)-97.0 ± 0.1 x 10(3) cfu for bacteria and 7.0 ± 0.1x 10(3)-96.0 ± 0.1 x 10(3) cfu for fungi) and microbial diversity were recorded in the gut of earthworms of the sawmill locations than those of the control site (17.5 ± 0.1 x10(3) cfu for bacteria and 4.5 ± 0.1 x 10(3) cfu for fungi). Streptococcus mutans and Proteus spp. were common in the gut of E. eugeniae, and L. violaceous from the study sawmills, while Streptococcus mutans were also identified in H. africanus, but absent in the gut of E. eugeniae from the control site. Cellulase (48.67 ± 0.02 mg/g) and lipase (1.81 ± 0.01 mg/g) activities were significantly higher (p < 0.05) in the gut of earthworms from the control site than those of the study sawmills. Furthermore, amylase (? and ?) activity was highest in the gut of earthworms from the sawmills. Variations observed in the gut microbial and digestive enzyme activities of earthworms from the study sawmills as compared to the control site suggests that earthworms, especially E. eugeniae, could be a better organism for use as bioremediator of wood wastes. PMID:25412548

  17. Easy method to examine single nerve fiber excitability and conduction parameters using intact nonanesthetized earthworms.

    PubMed

    Bähring, Robert; Bauer, Christiane K

    2014-09-01

    The generation and conduction of neuronal action potentials (APs) were the subjects of a cell physiology exercise for first-year medical students. In this activity, students demonstrated the all-or-none nature of AP generation, measured conduction velocity, and examined the dependence of the threshold stimulus amplitude on stimulus duration. For this purpose, they used the median giant nerve fiber (MGF) in the ventral nerve cord of the common earthworm (Lumbricus terrestris). Here, we introduce a specialized stimulation and recording chamber that the nonanesthetized earthworm enters completely unforced. The worm resides in a narrow round duct with silver electrodes on the bottom such that individual APs of the MGF can be elicited and recorded superficially. Our experimental setup combines several advantages: it allows noninvasive single fiber AP measurements taken from a nonanesthetized animal that is yet restrained. Students performed the experiments with a high success rate. According to the data acquired by the students, the mean conduction velocity of the MGF was 30.2 m/s. From the amplitude-duration relationship for threshold stimulation, rheobase and chronaxie were graphically determined by the students according to Lapicque's method. The mean rheobase was 1.01 V, and the mean chronaxie was 0.06 ms. The acquired data and analysis results are of high quality, as deduced from critical examination based on the law of Weiss. In addition, we provide video material, which was also used in the practical course. PMID:25179616

  18. Feasibility of utilization of horse dung spiked filter cake in vermicomposters using exotic earthworm Eisenia foetida.

    PubMed

    Sangwan, Pritam; Kaushik, C P; Garg, V K

    2008-05-01

    This contribution reports the potential of vermicomposting technology in the management of horse dung (HD) spiked sugar mill filter cake (SMFC) using an epigeic earthworm Eisenia foetida under laboratory conditions. A total of six vermicomposters filled with different ratios of HD and SMFC were maintained for this study. The growth and fecundity of E. foetida was monitored for 12 weeks. Maximum growth was recorded in 90% HD+10% SMFC feed mixture containing vermicomposter. Earthworms' biomass gain and reproduction was favorably up to 50% HD+50% SMFC feed composition. Maximum cocoons were also recorded in 90% HD+10% SMFC feed mixtures, however increasing proportions of SMFC in different vermicomposters affected the growth and fecundity of worms. A significant decrease in C:N ratio and increase in total kjeldahl nitrogen, total available phosphorus and calcium contents was recorded. The heavy metals content was higher in the vermicompost obtained in all the reactors than initial feed substrates. Based on investigations it is concluded that vermicomposting could be an alternative technology for the management of filter cake if it is mixed in 1:1 ratio with horse dung. PMID:17574845

  19. Diversity of Glycosyl Hydrolases from Cellulose-Depleting Communities Enriched from Casts of Two Earthworm Species? †

    PubMed Central

    Beloqui, Ana; Nechitaylo, Taras Y.; López-Cortés, Nieves; Ghazi, Azam; Guazzaroni, María-Eugenia; Polaina, Julio; Strittmatter, Axel W.; Reva, Oleg; Waliczek, Agnes; Yakimov, Michail M.; Golyshina, Olga V.; Ferrer, Manuel; Golyshin, Peter N.

    2010-01-01

    The guts and casts of earthworms contain microbial assemblages that process large amounts of organic polymeric substrates from plant litter and soil; however, the enzymatic potential of these microbial communities remains largely unexplored. In the present work, we retrieved carbohydrate-modifying enzymes through the activity screening of metagenomic fosmid libraries from cellulose-depleting microbial communities established with the fresh casts of two earthworm species, Aporrectodea caliginosa and Lumbricus terrestris, as inocula. Eight glycosyl hydrolases (GHs) from the A. caliginosa-derived community were multidomain endo-?-glucanases, ?-glucosidases, ?-cellobiohydrolases, ?-galactosidase, and ?-xylosidases of known GH families. In contrast, two GHs derived from the L. terrestris microbiome had no similarity to any known GHs and represented two novel families of ?-galactosidases/?-arabinopyranosidases. Members of these families were annotated in public databases as conserved hypothetical proteins, with one being structurally related to isomerases/dehydratases. This study provides insight into their biochemistry, domain structures, and active-site architecture. The two communities were similar in bacterial composition but significantly different with regard to their eukaryotic inhabitants. Further sequence analysis of fosmids and plasmids bearing the GH-encoding genes, along with oligonucleotide usage pattern analysis, suggested that those apparently originated from Gammaproteobacteria (pseudomonads and Cellvibrio-like organisms), Betaproteobacteria (Comamonadaceae), and Alphaproteobacteria (Rhizobiales). PMID:20622123

  20. Collision Avoidance for Airport Traffic Simulation Evaluation

    NASA Technical Reports Server (NTRS)

    Jones, Denise R.; Prinzel, Lawrence J., III; Shelton, Kevin J.; Bailey, Randall E.; Otero, Sharon D.; Barker, Glover D.

    2010-01-01

    A Collision Avoidance for Airport Traffic (CAAT) concept for the airport Terminal Maneuvering Area (TMA) was evaluated in a simulation study at the National Aeronautics and Space Administration (NASA) Langley Research Center. CAAT is being designed to enhance surface situation awareness and provide cockpit alerts of potential conflicts during runway, taxi, and low altitude air-to-air operations. The purpose of the study was to evaluate pilot reaction to conflict events in the TMA near the airport, different alert timings for various scenarios, alerting display concepts, and directive alerting concepts. This paper gives an overview of the conflict detection and resolution (CD&R) concept, simulation study, and test results

  1. Collision Avoidance for Airport Traffic Concept Evaluation

    NASA Technical Reports Server (NTRS)

    Jones, Denise R.; Prinzel, Lawrence J., III; Otero, Sharon D.; Barker, Glover D.

    2009-01-01

    An initial Collision Avoidance for Airport Traffic (CAAT) concept for the Terminal Maneuvering Area (TMA) was evaluated in a simulation study at the National Aeronautics and Space Administration (NASA) Langley Research Center. CAAT is being designed to enhance surface situation awareness and provide cockpit alerts of potential conflicts during runway, taxi, and low altitude air-to-air operations. The purpose of the study was to evaluate the initial concept for an aircraft-based method of conflict detection and resolution (CD&R) in the TMA focusing on conflict detection algorithms and alerting display concepts. This paper gives an overview of the CD&R concept, simulation study, and test results.

  2. Conditioned taste avoidance induced by lactose ingestion in adult rats.

    PubMed

    DiBattista, D

    1990-02-01

    Because adult rats have very low levels of the intestinal enzyme lactase, the ingestion of appreciable quantities of the disaccharide lactose may cause gastrointestinal distress. The present experiment was designed to demonstrate that adult rats will learn to avoid previously neutral stimuli which have been paired with lactose ingestion. Adult rats ingested both a novel solution [either tap water (WA) or 0.1% saccharin (SA)] and a novel food substance (49% powdered lab chow + 50% added disaccharide + 1% saccharin) during a single conditioning session. The added disaccharide was either sucrose (group SU-SA), lactose (groups HL-SA and HL-WA), or equal amounts of these two disaccharides (group LL-SA); a fifth group (LC-SA) consumed a sucrose-containing diet to which lithium chloride was added (5 mg per 1 g of diet). Separate feeding tests and drinking tests, carried out over several weeks, were used to assess the extent of conditioned taste avoidance. In the four feeding tests, rats were allowed to ingest powdered lab chow with added saccharin (but without added disaccharide), while in the four drinking tests, rats chose between tap water and a 0.1% saccharin solution. Group HL-SA demonstrated a substantial conditioned avoidance in both feeding and drinking tests, but group HL-WA showed avoidance only in feeding tests. Conditioned avoidance was weak in group LL-SA; the strongest avoidance was observed in lithium chloride-treated rats (group LC-SA). Results are related to previous research and to the hypothesis that a learned avoidance of milk may facilitate the weaning process in mammals. PMID:2333339

  3. Avoidance response of a terrestrial salamander ( Ambystoma macrodactylum ) to chemical alarm cues

    Microsoft Academic Search

    Douglas P. Chivers; Joseph M. Kiesecker; Michael T. Anderson; Erica L. Wildy; Andrew R. Blaustein

    1996-01-01

    Organisms from a wide variety of taxonomic groups possess chemical alarm cues that are important in mediating predator avoidance. However, little is known about the presence of such alarm cues in most amphibians, and in particular terrestrial salamanders. In this study we tested whether adult long-toed salamanders (Ambystoma macrodactylum) showed an avoidance response to stimuli from injured conspecifics. Avoidance of

  4. Ligand arsenic complexation and immunoperoxidase detection of metallothionein in the earthworm Lumbricus rubellus inhabiting arsenic-rich soil.

    PubMed

    Langdon, C J; Winters, C; Stürzenbaum, S R; Morgan, A J; Charnock, J M; Meharg, A A; Piearce, T G; Lee, P H; Semple, K T

    2005-04-01

    Although earthworms have been found to inhabit arsenic-rich soils in the U.K., the mode of arsenic detoxification is currently unknown. Biochemical analyses and subcellular localization studies have indicated that As3+-thiol complexes may be involved; however, it is not known whether arsenic is capable of inducing the expression of metallothionein (MT) in earthworms. The specific aims of this paper were (a) to detect and gain an atomic characterization of ligand complexing by X-ray absorption spectrometry (XAS), and (b) to employ a polyclonal antibody raised against an earthworm MT isoform (w-MT2) to detect and localize the metalloprotein by immunoperoxidase histochemistry in the tissues of earthworms sampled from arsenic-rich soil. Data suggested that the proportion of arsenate to sulfur-bound species varies within specific earthworm tissues. Although some arsenic appeared to be in the form of arsenobetaine, the arsenic within the chlorogogenous tissue was predominantly coordinated with S in the form of -SH groups. This suggests the presence of an As::MT complex. Indeed, MT was detectable with a distinctly localized tissue and cellular distribution. While MT was not detectable in the surface epithelium or in the body wall musculature, immunoperoxidase histochemistry identified the presence of MT in chloragocytes around blood vessels, within the typhlosolar fold, and in the peri-intestinal region. Focal immunostaining was also detectable in a cohort of cells in the intestinal wall. The results of this study support the hypothesis that arsenic induces MT expression and is sequestered by the metalloprotein in certain target cells and tissues. PMID:15871235

  5. Bioavailability and release of nonextractable (bound) residues of chiral cycloxaprid using geophagous earthworm Metaphire guillelmi in rice paddy soil.

    PubMed

    Liu, Xuanqi; Xu, Xiaoyong; Zhang, Hanxue; Li, Chao; Shao, Xusheng; Ye, Qingfu; Li, Zhong

    2015-09-01

    The widespread adoption of neonicotinoids has led to a move away from integrated pest management (IPM) and caused adverse effects on non-target invertebrate species. Due to their living in close contact with and consuming large amounts of soil, earthworms are a model organism used to study bioaccumulation. We investigated the bioaccumulation and release of bound, or non-extractable, residues (BRs) of (14)C labeled racemic cycloxaprid (CYC) and its individual enantiomers by the geophagous earthworm Metaphire guillelmi. In a previous work, the fraction of BRs of (14)C-CYC individual enantiomers reached up to 70-85% of the initially spiked radioactivity after 100d of treatment. The bulk volume of the soil was then diluted by a factor of 15 with fresh soil. Here we showed that after earthworms lived in the soil-bound residues for 28d, 11-25% of the previously bound radioactivity in soil was extractable by solvent, mineralized to CO2, and accumulated in earthworm tissues. While earthworms were exposed to (14)C-CYC a two-compartment accumulation model could explain the bio-accumulation as individual enantiomers. At the end of the experiment, the biota-sediment accumulation factors were between 0.59 and 0.82, which suggested CYC immobilization in the soil resulted in its bioavailability being reduced which enhanced its degradation. Additionally, the elimination of CYC individual enantiomers from M. guillelmi was fitted to an availability-adjusted decay model with a half-life of 9d. Stereoselective release or bioavailability between CYC enantiomers was not observed. These results provide the important data about the release of BRs of CYC and potential transfer in the food chain to support the long-term environmental risk assessment of neonicotinoids. PMID:25933294

  6. Avoiding Differences Spanning Trees in Grid Graphs

    E-print Network

    Zeilberger, Doron

    Avoiding Differences Spanning Trees in Grid Graphs The Firefighter Problem Automated Proof and Discovery #12;Avoiding Differences Spanning Trees in Grid Graphs The Firefighter Problem Automated Proof and Discovery #12;Avoiding Differences Spanning Trees in Grid Graphs The Firefighter Problem Outline 1 Avoiding

  7. Accumulation of hexahydro-1,3,5-trinitro-1,3,5-triazine by the earthworm Eisenia andrei in a sandy loam soil.

    PubMed

    Sarrazin, Manon; Dodard, Sabine G; Savard, Kathleen; Lachance, Bernard; Robidoux, Pierre Y; Kuperman, Roman G; Hawari, Jalal; Ampleman, Guy; Thiboutot, Sonia; Sunahara, Geoffrey I

    2009-10-01

    The heterocyclic polynitramine hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a highly energetic compound found as a soil contaminant at some defense installations. Although RDX is not lethal to soil invertebrates at concentrations up to 10,000 mg/kg, it decreases earthworm cocoon formation and juvenile production at environmentally relevant concentrations found at contaminated sites. Very little is known about the uptake of RDX in earthworms and the potential risks for food-chain transfer of RDX in the environment. Toxicokinetic studies were conducted to quantify the bioaccumulation factors (BAFs) using adult earthworms (Eisenia andrei) exposed for up to 14 d to sublethal concentrations of nonlabeled RDX or [14C]RDX in a Sassafras sandy loam soil. High-performance liquid chromatography of acetonitrile extracts of tissue and soil samples indicated that nonlabeled RDX can be accumulated by the earthworm in a concentration- and time-dependent manner. The BAF, expressed as the earthworm tissue to soil concentration ratio, decreased from 6.7 to 0.1 when the nominal soil RDX concentrations were increased from 1 to 10,000 mg/kg. Tissue concentrations were comparable in earthworms exposed to nonlabeled RDX or [14C]RDX. The RDX bioaccumulation also was estimated using the kinetically derived model (BAFK), based on the ratio of the uptake to elimination rate constants. The established BAFK of 3.6 for [14C]RDX uptake was consistent with the results for nonlabeled RDX. Radioactivity also was present in the tissue residues of [14C]RDX-exposed earthworms following acetonitrile extraction, suggesting the formation of nonextractable [14C]RDX metabolites associated with tissue macromolecules. These findings demonstrated a net accumulation of RDX in the earthworm and the potential for food-chain transfer of RDX to higher-trophic-level receptors. PMID:19432505

  8. Obstacle avoidance sonar for submarines

    Microsoft Academic Search

    Albert C. Dugas; Kenneth M. Webman

    2002-01-01

    The Advanced Mine Detection Sonar (AMDS) system was designed to operate in poor environments with high biological and\\/or shallow-water boundary conditions. It provides increased capability for active detection of volume, close-tethered, and bottom mines, as well as submarine and surface target active\\/passive detection for ASW and collision avoidance. It also provides bottom topography mapping capability for precise submarine navigation in

  9. Testing

    MedlinePLUS

    ... curesma.org > learn about sma > causes & diagnoses > testing Testing An SMA diagnosis must be confirmed through genetic ... and must be identified through further testing. Prenatal Testing Prenatal testing is used to determine if a ...

  10. ELF communications system ecological monitoring program: Soil arthropods and earthworms

    NASA Astrophysics Data System (ADS)

    Snider, Richard J.; Snider, Renate M.

    1995-04-01

    Based on analysis of years grouped by pre-ELF and operational periods, density fluctuations of arthropods (Collembola and mites) were, in some taxa, significantly different between sites; in others, differences between year groups were significant within either of the study sites. No consistent patterns were seen at the level of species or higher taxa. In some species, effects of the 1988 drought may have carried over into 1989, the first year of antenna operation. Surface-active Collembola, velvet mites and carabid beetles did not alter their activity patterns following antenna activation (e.g., species predominantly spring-active remained spring-active). Although analyses routinely yielded significant differences with respect to total numbers captured in Test and Control, numbers alone were found to be unreliable estimators for disturbance, because a variety of potentially important factors other than EM fields were present. Weekly changes in relative numbers captured, however, showed that increases and decreases in activity were synchronous in the study sites. Carabid beetle activity, which is highly seasonal and governed mainly by reproductive processes, was not affected by EM fields.

  11. Effects of the Fungicide Benomyl on Earthworms in Laboratory Tests Under Tropical and Temperate Conditions

    Microsoft Academic Search

    Jörg Römbke; Marcos V. Garcia; Adam Scheffczyk

    2007-01-01

    Soil organisms play a crucial role in the terrestrial ecosystem. Plant protection products (PPPs) are known to affect soil\\u000a organisms and might have negative impacts on soil functions influenced by these organisms. Little research has been performed\\u000a to date on the impact of PPPs on tropical soil ecosystems. Therefore, in this study it was investigated whether the effects\\u000a of the

  12. N2O-Producing Microorganisms in the Gut of the Earthworm Aporrectodea caliginosa Are Indicative of Ingested Soil Bacteria

    PubMed Central

    Ihssen, Julian; Horn, Marcus A.; Matthies, Carola; Gößner, Anita; Schramm, Andreas; Drake, Harold L.

    2003-01-01

    The main objectives of this study were (i) to determine if gut wall-associated microorganisms are responsible for the capacity of earthworms to emit nitrous oxide (N2O) and (ii) to characterize the N2O-producing bacteria of the earthworm gut. The production of N2O in the gut of garden soil earthworms (Aporrectodea caliginosa) was mostly associated with the gut contents rather than the gut wall. Under anoxic conditions, nitrite and N2O were transient products when supplemental nitrate was reduced to N2 by gut content homogenates. In contrast, nitrite and N2O were essentially not produced by nitrate-supplemented soil homogenates. The most probable numbers of fermentative anaerobes and microbes that used nitrate as a terminal electron acceptor were approximately 2 orders of magnitude higher in the earthworm gut than in the soil from which the earthworms originated. The fermentative anaerobes in the gut and soil displayed similar physiological functionalities. A total of 136 N2O-producing isolates that reduced either nitrate or nitrite were obtained from high serial dilutions of gut homogenates. Of the 25 representative N2O-producing isolates that were chosen for characterization, 22 isolates exhibited >99% 16S rRNA gene sequence similarity with their closest cultured relatives, which in most cases was a soil bacterium, most isolates were affiliated with the gamma subclass of the class Proteobacteria or with the gram-positive bacteria with low DNA G+C contents, and 5 isolates were denitrifiers and reduced nitrate to N2O or N2. The initial N2O production rates of denitrifiers were 1 to 2 orders of magnitude greater than those of the nondenitrifying isolates. However, most nondenitrifying nitrate dissimilators produced nitrite and might therefore indirectly stimulate the production of N2O via nitrite-utilizing denitrifiers in the gut. The results of this study suggest that most of the N2O emitted by earthworms is due to the activation of ingested denitrifiers and other nitrate-dissimilating bacteria in the gut lumen. PMID:12620856

  13. The structure of the ovary and oogenesis in the earthworm, Dendrobaena veneta (Annelida, Clitellata).

    PubMed

    Siekierska, E

    2003-08-01

    The structure of the ovary and the type of oogenesis were determined in the earthworm Dendrobaena veneta (Oligochaeta, Haplotaxida, Lumbricidae) with histological, electron-microscopic and immunocytochemical methods. In this species the ovary is of the alimentary, nutrimentary type because it contains oocytes and the nurse cells (trophocytes). The ovarian stroma is built by somatic cells, the processes of which are connected to each other via numerous desmosomes. The somatic cells and their processes envelop the germ cells tightly and play a supportive role. Oogonia, oocytes and trophocytes are arranged in distinct zones in the ovary. Trophocytes form chains of cells, which are interconnected by intercellular bridges. Numerous microtubules are located within the latter. The oocytes are distally arranged in the ovary. Vitellogenesis involves both auto- and heterosyntheses. The results obtained were compared with the reports on oogenesis in other representatives of Annelida. PMID:12921708

  14. Micro-PIXE studies of Cd distribution in the nephridia of the earthworm Eisenia fetida (Oligochaeta)

    NASA Astrophysics Data System (ADS)

    Prinsloo, M. W.; Reinecke, S. A.; Przybylowicz, W. J.; Mesjasz-Przybylowicz, J.; Reinecke, A. J.

    1999-10-01

    The distribution and accumulation of Cd in the nephridia of earthworms of the species Eisenia fetida (Oligochaeta) was studied using the NAC nuclear microprobe. Worms were exposed to CdSO 4 in a cattle manure substrate. Elemental maps were obtained using the true elemental imaging system (dynamic analysis). It was found that at a substrate concentration of 300 mg kg -1 CdSO 4, Cd did accumulate in the nephridia, showing clear patterns in its distribution within this organ. It accumulated to the greatest extent in the region between the nephridiopore and first loop, and the urinary vasiculus, reaching values of 890 ± 40 mg kg -1 and 570 ± 20 mg kg -1 in these regions, respectively. This is in contrast to the lower concentrations in the body wall (76 ± 15 mg kg -1) of the worm.

  15. Three new earthworm species of the genus Polypheretima Michaelsen, 1934 (Oligochaeta: Megascolecidae) from Vietnam.

    PubMed

    Nguyen, Tung T; Tran, Binh T T; Nguyen, Anh D

    2015-01-01

    The paper provides descriptions of three new species of the earthworm genus Polypheretima Michaelsen, 1934 from Dong Nai Province, South Vietnam. They are named Po. cattienensis sp. nov., Po. militium sp. nov., and Po. cordata sp. nov.. All three species are characterized by spermathecal pores in 5/6/7 and the absence of genital markings. Po. cattienensis sp. nov. is distinguished by paired spermathecal pores and seven spermathecae per porus. Po. militium sp. nov. is diagnosed by paired spermathecal pores and a variable number of spermathecae, 21-40 altogether, with 7-17 in 5/6 and 11-23 in 6/7. Po. cordata sp. nov. is recognized by one pair of spermathecal pores in 5/6 and two in 6/7, by only one spermatheca per porus, and by a heart-shaped spermathecal ampulla.  PMID:25661234

  16. Earthworm-Derived Pore-Forming Toxin Lysenin and Screening of Its Inhibitors

    PubMed Central

    Sukumwang, Neelanun; Umezawa, Kazuo

    2013-01-01

    Lysenin is a pore-forming toxin from the coelomic fluid of earthworm Eisenia foetida. This protein specifically binds to sphingomyelin and induces erythrocyte lysis. Lysenin consists of 297 amino acids with a molecular weight of 41 kDa. We screened for cellular signal transduction inhibitors of low molecular weight from microorganisms and plants. The purpose of the screening was to study the mechanism of diseases using the obtained inhibitors and to develop new chemotherapeutic agents acting in the new mechanism. Therefore, our aim was to screen for inhibitors of Lysenin-induced hemolysis from plant extracts and microbial culture filtrates. As a result, we isolated all-E-lutein from an extract of Dalbergia latifolia leaves. All-E-lutein is likely to inhibit the process of Lysenin-membrane binding and/or oligomer formation rather than pore formation. Additionally, we isolated tyrosylproline anhydride from the culture filtrate of Streptomyces as an inhibitor of Lysenin-induced hemolysis. PMID:23965430

  17. Monocystis apporectodae sp. nov. (Protozoa: Apicomplexa: Eugregarinida), from an Indian earthworm Apporectodea trapezoides Duges.

    PubMed

    Bandyopadhyay, Probir K; Mallik, Partha; Göçmen, Bayram; Mitra, Amlan Kumar

    2006-01-01

    A survey aimed at exploring the endoparasitic acephaline gregarine diversity in South-western Bengal, detected a new species of the genus Monocystis Stein, 1848, that resides in the seminal vesicles of the earthworm, Apporectodea trapezoides Duges collected in the district of Bankura from alluvial soil. Monocystis apporectodae sp. nov. is a ribbon-like organism with one or more prominent constric-tions especially in some mature forms and measures 178.0-224.0 (203.0+/-5.0) microm x 37.0-58.0 (46.0+/-1.5) microm. The extreme ends are pointed. Its gametocysts are ovoid and measure 108.0-118.0 microm (113.0+/-1.1) x 79.0-89.0 (83.0+/-1.1) microm. Oocysts are navicular in shape. The length of the oocysts ranges from 10.0-14.6 and the width, from 5.5-8.1 microm. PMID:17106856

  18. Transcriptional responses of earthworm (Eisenia fetida) exposed to naphthenic acids in soil.

    PubMed

    Wang, Jie; Cao, Xiaofeng; Sun, Jinhua; Chai, Liwei; Huang, Yi; Tang, Xiaoyan

    2015-09-01

    In this study, earthworms (Eisenia fetida) were exposed to commercial NAs contaminated soil, and changes in the levels of reactive oxygen species (ROS) and gene expressions of their defense system were monitored. The effects on the gene expression involved in reproduction and carcinogenesis were also evaluated. Significant increases in ROS levels was observed in NAs exposure groups, and the superoxide dismutase (SOD) and catalase (CAT) genes were both up-regulated at low and medium exposure doses, which implied NAs might exert toxicity by oxidative stress. The transcription of CRT and HSP70 coincided with oxidative stress, which implied both chaperones perform important functions in the protection against oxidative toxicity. The upregulation of TCTP gene indicated a potential adverse effect of NAs to terrestrial organisms through induction of carcinogenesis, and the downregulation of ANN gene indicated that NAs might potentially result in deleterious reproduction effects. PMID:25984985

  19. Potential utilization of bagasse as feed material for earthworm Eisenia fetida and production of vermicompost.

    PubMed

    Bhat, Sartaj Ahmad; Singh, Jaswinder; Vig, Adarsh Pal

    2015-01-01

    In the present work bagasse (B) i.e waste of the sugar industry, was fed to Eisenia fetida with cattle dung (CD) support as feed material at various ratios (waste: CD) of 0:100 (B0), 25:75 (B25), 50:50 (B50), 75:25 (B75) and 100:0 (B100) on dry weight basis. Co-composting with cattle dung helped to improve their acceptability for E. fetida and also improved physico-chemical characteristics. Best appropriate ratio for survival, maximum growth and population buildup of E. fetida was determined by observing population buildup, growth rate, biomass, mortality and cocoon formation. Minimum mortality and highest population size of worms was observed in 50:50 (B50) ratio. Increasing concentrations of wastes significantly affected the growth and reproduction of worms. Nutrients like nitrogen, phosphorus and sodium increased from pre-vermicompost to post-vermicompost, while organic carbon, and C:N ratio decreased in all the end products of post-vermicomposting. Heavy metals decreased significantly from initial except zinc, iron and manganese which increased significantly. Scanning electron microscopy (SEM) was used to recognize the changes in texture in the pre and post-vermicomposted samples. The post-vermicomposted ratios in the presence of earthworms validate more surface changes that prove to be good manure. The results observed from the present study indicated that the earthworm E. fetida was able to change bagasse waste into nutrient-rich manure and thus play a major role in industrial waste management. PMID:25625035

  20. Obstacle-avoiding navigation system

    DOEpatents

    Borenstein, Johann (Ann Arbor, MI); Koren, Yoram (Ann Arbor, MI); Levine, Simon P. (Ann Arbor, MI)

    1991-01-01

    A system for guiding an autonomous or semi-autonomous vehicle through a field of operation having obstacles thereon to be avoided employs a memory for containing data which defines an array of grid cells which correspond to respective subfields in the field of operation of the vehicle. Each grid cell in the memory contains a value which is indicative of the likelihood, or probability, that an obstacle is present in the respectively associated subfield. The values in the grid cells are incremented individually in response to each scan of the subfields, and precomputation and use of a look-up table avoids complex trigonometric functions. A further array of grid cells is fixed with respect to the vehicle form a conceptual active window which overlies the incremented grid cells. Thus, when the cells in the active window overly grid cell having values which are indicative of the presence of obstacles, the value therein is used as a multiplier of the precomputed vectorial values. The resulting plurality of vectorial values are summed vectorially in one embodiment of the invention to produce a virtual composite repulsive vector which is then summed vectorially with a target-directed vector for producing a resultant vector for guiding the vehicle. In an alternative embodiment, a plurality of vectors surrounding the vehicle are computed, each having a value corresponding to obstacle density. In such an embodiment, target location information is used to select between alternative directions of travel having low associated obstacle densities.

  1. Observation on Monocystis constricta n. sp. (Protozoa: Apicomplexa: Monocystidae) from an Indian earthworm, Eutyphoeus quaripapillatus Michelsen, 1907.

    PubMed

    Bandyopadhyay, Probir K; Mitra, Amlan Kumar; Göçmen, Bayram

    2009-01-01

    A biodiversity survey of aseptate gregarines in earthworm hosts in the Calcutta district of West Bengal State revealed the existence of a new species of aseptate gregarine under the genus Monocystis Stein, 1848. The monocystid gregarines obtained from the earthworm host, Eutyphoeus quaripapillatus Michelsen, 1907 have been identified as a new species. The mucron was indistinct. The gamonts are elongated, ovoid, have a hood like structure at the anterior end and measure 150.1-212.4 (188.1+/-2.1) micromx66.1-112.1 (72.3+/-1.1) microm. The gametocysts are ellipsoid and measure 92.3-136.3 microm (111.2+/-2.1)x78.3-114.4 microm (82.6+/-3.6) microm. Prominent syzygy was apparent. Oocysts are navicular, measuring 14.1-22.3 (18.1+/-3.2) micromx9.1-15.2 (11.9+/-1.1) microm. PMID:19851977

  2. The modification of avoidance learning pain behaviors

    Microsoft Academic Search

    Wilbert E. Fordyce; John L. Shelton; Diana E. Dundore

    1982-01-01

    This study demonstrates a procedural innovation designed to modify chronic pain behaviors which have been acquired through avoidance learning. Discussion focuses on avoidance learning as a seldom-investigated factor in the acquisition and maintenance of chronic pain behaviors.

  3. Avoiding Lexical Ambiguities: Does Prior Experience Help? 

    E-print Network

    Nierop, Katharine

    2008-06-27

    The present study examined whether speakers avoided the production of lexically ambiguous target labels in a referential communication task (e.g., avoiding the ambiguous bare homophone mouse when pictures of both a computer ...

  4. Planning under uncertainty for dynamic collision avoidance

    E-print Network

    Temizer, Selim, 1977-

    2011-01-01

    We approach dynamic collision avoidance problem from the perspective of designing collision avoidance systems for unmanned aerial vehicles. Before unmanned aircraft can fly safely in civil airspace, robust airborne collision ...

  5. Testing.

    ERIC Educational Resources Information Center

    Killoran, James, Ed.

    1984-01-01

    This journal issue addresses the issue of testing in the social studies classroom. The first article, "The Role of Testing" (Bragaw), focuses on the need for tests to reflect the objectives of the study completed. The varying functions of pop quizzes, weekly tests, and unit tests are explored. "Testing Thinking Processes" (Killoran, Zimmer, and…

  6. Bioremediation of aerobically treated distillery sludge mixed with cow dung by using an epigeic earthworm Eisenia fetida

    Microsoft Academic Search

    Surendra Suthar

    2008-01-01

    The potential of the epigeic earthworm Eisenia fetida to stabilize sludge?(generated from a distillation unit of the sugar industry) mixed with cow dung, in different proportions\\u000a i.e. 20% (T1), 40% (T2), 60% (T3) and 80% (T4) has been studied under laboratory conditions for 90 days. The?ready vermicompost was evaluated for its’ different physico-chemical\\u000a parameters using standard methods. At the end of

  7. The forms and bioavailability of phosphorus in integrated vertical flow constructed wetland with earthworms and different substrates.

    PubMed

    Xu, Defu; Wang, Lin; Li, Huili; Li, Yingxue; Howard, Alan; Guan, Yidong; Li, Jiuhai; Xu, Hui

    2015-09-01

    A sequential extraction method was utilized to analyze seven forms of P in an integrated vertical-flow constructed wetland (IVFCW) containing earthworms and different substrates. The aluminum-bound P (Al-P) content was found to be lower, and the occluded P (Oc-P) content was higher in the IVFCW. The addition of earthworms into the influent chamber of IVFCW increased the exchange P (Ex-P), iron-bound P (Fe-P), calcium bound P (Ca-P), Oc-P, detritus-bound (De-P) and organic P (Org-P) content in the influent chamber, and also enhanced P content uptake by wetland plants. A significantly positive correlation between P content of above-ground wetland plants and the Ex-P, Fe-P, Oc-P and Org-P content in the rhizosphere was found (P<0.05), which indicated that the Ex-P, Fe-P, Oc-P and Org-P could be bio-available P. The Ex-P, Fe-P, De-P, Oc-P and Ca-P content of the influent chamber was higher where the substrate contained a mixture of Qing sand and river sand rather than only river sand. Also the IVFCW with earthworms and both Qing sand and river sand had a higher removal efficiency of P, which was related to higher P content uptake by wetland plants and P retained in IVFCW. These findings suggest that addition of earthworms in IVFCW increases the bioavailable P content, resulting in enhanced P content uptake by wetland plants. PMID:26025066

  8. The effects of low lead levels on the growth and reproduction of the African earthworm Eudrilus eugeniae (Oligochaeta)

    Microsoft Academic Search

    M. S. Maboeta; A. J. Reinecke; S. A. Reinecke

    1999-01-01

    The effects of sublethal concentrations of lead nitrate on the growth and reproduction of the African composting earthworm\\u000a species, Eudrilus eugeniae, was studied by exposing worms in an organic substrate to lead-nitrate-contaminated food over a period of 76 days. The results\\u000a revealed that growth was initially affected negatively by the presence of lead, while the maturation rate and cocoon production

  9. Links between the detritivore and the herbivore system: effects of earthworms and Collembola on plant growth and aphid development

    Microsoft Academic Search

    Stefan Scheu; Anne Theenhaus; T. Hefin Jones

    1999-01-01

    Effects of Collembola (Heteromurus nitidus and Onychiurus scotarius) and earthworms (Aporrectodea caliginosa and Octolasion tyrtaeum) on the growth of two plant species from different functional groups (Poa annua and Trifolium repens), and on the development of aphids (Myzus persicae) were investigated in a laboratory experiment lasting 20?weeks. Using soil from a fallow site which had been set aside for\\u000a about

  10. Analysis of the Diversity of Substrate Utilisation of Soil Bacteria Exposed to Cd and Earthworm Activity Using Generalised Additive Models

    PubMed Central

    Muńiz, Selene; Lacarta, Juan; Pata, María P.; Jiménez, Juan José; Navarro, Enrique

    2014-01-01

    Biolog EcoPlates™ can be used to measure the carbon substrate utilisation patterns of microbial communities. This method results in a community-level physiological profile (CLPP), which yields a very large amount of data that may be difficult to interpret. In this work, we explore a combination of statistical techniques (particularly the use of generalised additive models [GAMs]) to improve the exploitation of CLPP data. The strength of GAMs lies in their ability to address highly non-linear relationships between the response and the set of explanatory variables. We studied the impact of earthworms (Aporrectodea caliginosa Savigny 1826) and cadmium (Cd) on the CLPP of soil bacteria. The results indicated that both Cd and earthworms modified the CLPP. GAMs were used to assess time-course changes in the diversity of substrate utilisation (DSU) using the Shannon-Wiener index. GAMs revealed significant differences for all treatments (compared to control -S-). The Cd exposed microbial community presented very high metabolic capacities on a few substrata, resulting in an initial acute decrease of DSU (i.e. intense utilization of a few carbon substrata). After 54 h, and over the next 43 h the increase of the DSU suggest that other taxa, less dominant, reached high numbers in the wells containing sources that are less suitable for the Cd-tolerant taxa. Earthworms were a much more determining factor in explaining time course changes in DSU than Cd. Accordingly, Ew and EwCd soils presented similar trends, regardless the presence of Cd. Moreover, both treatments presented similar number of bacteria and higher than Cd-treated soils. This experimental approach, based on the use of DSU and GAMs allowed for a global and statistically relevant interpretation of the changes in carbon source utilisation, highlighting the key role of earthworms on the protection of microbial communities against the Cd. PMID:24416339

  11. 'Systems toxicology' approach identifies coordinated metabolic responses to copper in a terrestrial non-model invertebrate, the earthworm Lumbricus rubellus

    Microsoft Academic Search

    Jacob G Bundy; Jasmin K Sidhu; Faisal Rana; David J Spurgeon; Claus Svendsen; Jodie F Wren; Stephen R Stürzenbaum; A John Morgan; Peter Kille

    2008-01-01

    BACKGROUND: New methods are needed for research into non-model organisms, to monitor the effects of toxic disruption at both the molecular and functional organism level. We exposed earthworms (Lumbricus rubellus Hoffmeister) to sub-lethal levels of copper (10–480 mg\\/kg soil) for 70 days as a real-world situation, and monitored both molecular (cDNA transcript microarrays and nuclear magnetic resonance-based metabolic profiling: metabolomics)

  12. Comparative proteomic analysis of differentially expressed proteins in the earthworm Eisenia fetida during Escherichia coli O157:H7 stress.

    PubMed

    Wang, Xing; Chang, Li; Sun, Zhenjun; Zhang, Yufeng

    2010-12-01

    Escherichia coli O157:H7 is an intestine-inhabiting bacterium associated with many severe disease outbreaks worldwide. It may enter the soil environment with the excreta of infected animals (e.g., horses, cattle, chickens) and humans. Earthworms can protect themselves against invading pathogens because of their efficient innate defense system. Identification of differential proteomic responses to E. coli O157:H7 may provide a better understanding of the survival mechanisms of the earthworm Eisenia fetida that lives in E. coli O157:H7-polluted environments. Whole earthworm extracts, collected at days 7, 14, 21, and 28 after E. coli O157:H7 stress, were analyzed by two-dimensional gel electrophoresis and quantitative image analysis. In total, 124 proteins demonstrated significant regulation at least at one time point, and 52 proteins were identified by matrix-assisted laser desorption/ionization-tandem time-of-flight mass spectrometry and database searching. Compared with control samples, 11 protein spots were up-regulated and 41 were down-regulated for at least one time point. The identified proteins, including heat shock protein 90, fibrinolytic protease 0, gelsolin-like protein, lombricine kinase, coelomic cytolytic factor-1, manganous superoxide dismutase, catalase, triosephosphate isomerase, extracellular globin-4, lysenin, intermediate filament protein, and glyceraldehyde-3-phosphate dehydrogenase, are involved in several processes, including transcription, translation, the tricarboxylic acid cycle, and the glucose metabolic process. Thus, our study provides a functional profile of the E. coli O157:H7-responsive proteins in earthworms. We suggest that the variable levels and trends in these spots on the gel may be useful as biomarker profiles to investigate E. coli O157:H7 contamination levels in soils. PMID:20863058

  13. Rapid isocratic HPLC quantification of metallothionein-like proteins as biomarkers for cadmium exposure in the earthworm Eisenia andrei

    Microsoft Academic Search

    Aristocle Ndayibagira; Geoffrey I. Sunahara; Pierre Yves Robidoux

    2007-01-01

    Metallothioneins (MTs) are regarded as sensitive biomarkers of cadmium (Cd) exposure in a number of organisms. An isocratic high-performance liquid chromatography (HPLC) method using the fluorophore ammonium-7-fluorobenz-2-oxa-1,3-diazole-4-sulfonate (SBD-F) and UV detection was developed for the quantification of MT-like proteins (MTLPs) in earthworm. This method was developed using a rabbit MT (MT-1) standard, and optimized concentrations of reagents including EDTA, SBD-F,

  14. Detection and avoidance of errors in computer software

    NASA Technical Reports Server (NTRS)

    Kinsler, Les

    1989-01-01

    The acceptance test errors of a computer software project to determine if the errors could be detected or avoided in earlier phases of development. GROAGSS (Gamma Ray Observatory Attitude Ground Support System) was selected as the software project to be examined. The development of the software followed the standard Flight Dynamics Software Development methods. GROAGSS was developed between August 1985 and April 1989. The project is approximately 250,000 lines of code of which approximately 43,000 lines are reused from previous projects. GROAGSS had a total of 1715 Change Report Forms (CRFs) submitted during the entire development and testing. These changes contained 936 errors. Of these 936 errors, 374 were found during the acceptance testing. These acceptance test errors were first categorized into methods of avoidance including: more clearly written requirements; detail review; code reading; structural unit testing; and functional system integration testing. The errors were later broken down in terms of effort to detect and correct, class of error, and probability that the prescribed detection method would be successful. These determinations were based on Software Engineering Laboratory (SEL) documents and interviews with the project programmers. A summary of the results of the categorizations is presented. The number of programming errors at the beginning of acceptance testing can be significantly reduced. The results of the existing development methodology are examined for ways of improvements. A basis is provided for the definition is a new development/testing paradigm. Monitoring of the new scheme will objectively determine its effectiveness on avoiding and detecting errors.

  15. Straightforward assay for quantification of social avoidance in Drosophila melanogaster.

    PubMed

    Fernandez, Robert W; Nurilov, Marat; Feliciano, Omar; McDonald, Ian S; Simon, Anne F

    2014-01-01

    Drosophila melanogaster is an emerging model to study different aspects of social interactions. For example, flies avoid areas previously occupied by stressed conspecifics due to an odorant released during stress known as the Drosophila stress odorant (dSO). Through the use of the T-maze apparatus, one can quantify the avoidance of the dSO by responder flies in a very affordable and robust assay. Conditions necessary to obtain a strong performance are presented here. A stressful experience is necessary for the flies to emit dSO, as well as enough emitter flies to cause a robust avoidance response to the presence of dSO. Genetic background, but not their group size, strongly altered the avoidance of the dSO by the responder flies. Canton-S and Elwood display a higher performance in avoiding the dSO than Oregon and Samarkand strains. This behavioral assay will allow identification of mechanisms underlying this social behavior, and the assessment of the influence of genes and environmental conditions on both emission and avoidance of the dSO. Such an assay can be included in batteries of simple diagnostic tests used to identify social deficiencies of mutants or environmental conditions of interest. PMID:25549275

  16. Using Next-Generation Sequencing to Analyse the Diet of a Highly Endangered Land Snail (Powelliphanta augusta) Feeding on Endemic Earthworms

    PubMed Central

    Boyer, Stéphane; Wratten, Stephen D.; Holyoake, Andrew; Abdelkrim, Jawad; Cruickshank, Robert H.

    2013-01-01

    Predation is often difficult to observe or quantify for species that are rare, very small, aquatic or nocturnal. The assessment of such species’ diet can be conducted using molecular methods that target prey DNA remaining in predators’ guts and faeces. These techniques do not require high taxonomic expertise, are applicable to soft-bodied prey and allow for identification at the species level. However, for generalist predators, the presence of mixed prey DNA in guts and faeces can be a major impediment as it requires development of specific primers for each potential prey species for standard (Sanger) sequencing. Therefore, next generation sequencing methods have recently been applied to such situations. In this study, we used 454-pyrosequencing to analyse the diet of Powelliphantaaugusta, a carnivorous landsnail endemic to New Zealand and critically endangered after most of its natural habitat has been lost to opencast mining. This species was suspected to feed mainly on earthworms. Although earthworm tissue was not detectable in snail faeces, earthworm DNA was still present in sufficient quantity to conduct molecular analyses. Based on faecal samples collected from 46 landsnails, our analysis provided a complete map of the earthworm-based diet of P. augusta. Predated species appear to be earthworms that live in the leaf litter or earthworms that come to the soil surface at night to feed on the leaf litter. This indicates that P. augusta may not be selective and probably predates any earthworm encountered in the leaf litter. These findings are crucial for selecting future translocation areas for this highly endangered species. The molecular diet analysis protocol used here is particularly appropriate to study the diet of generalist predators that feed on liquid or soft-bodied prey. Because it is non-harmful and non-disturbing for the studied animals, it is also applicable to any species of conservation interest. PMID:24086671

  17. Behavioural inbreeding avoidance in wild African elephants

    Microsoft Academic Search

    ELIZABETH A. ARCHIE; JULIE A. HOLLISTER-SMITH; JOYCE H. POOLE; PHYLLIS C. LEE; CYNTHIA J. MOSS; JÉSUS E. MALDONADO; ROBERT C. FLEISCHER; SUSAN C. ALBERTS

    2007-01-01

    The costs of inbreeding depression, as well as the opportunity costs of inbreeding avoidance, determine whether and which mechanisms of inbreeding avoidance evolve. In African ele- phants, sex-biased dispersal does not lead to the complete separation of male and female relatives, and so individuals may experience selection to recognize kin and avoid inbreed- ing. However, because estrous females are rare

  18. Real time obstacle avoidance for redundant robot

    Microsoft Academic Search

    Guoxiang Ping; Bing Wei; Xianglong Li; Xiang Luo

    2009-01-01

    Real-time obstacle avoidance for redundant robot is always of consequence in the field of robot research. According to the mechanism of the human arm movement in obstacle avoidance, an artificial safety zone around the obstacle in the operational space is defined. Based on the artificial safety zone, a unique technique of real-time collision avoidance for position controlled robot is proposed

  19. Tomographic patient registration and conformal avoidance tomotherapy

    Microsoft Academic Search

    Jennifer Stacy Aldridge

    1999-01-01

    Development of tomotherapy has led to the emergence of several processes, providing the basis for many unique investigative opportunities. These processes include setup verification, tomographic verification, megavoltage dose reconstruction, and conformal avoidance tomotherapy. Setup verification and conformal avoidance tomotherapy, in particular, are two closely intertwined matters. In order to avoid critical structures located within or adjacent to indistinct tumor regions,

  20. Growth Inhibition and Altered Gene Transcript Levels in Earthworms (Eisenia fetida) Exposed to 2,2',4,4'-Tetrabromodiphenyl Ether.

    PubMed

    Xu, Xiang-Bo; Shi, Ya-Juan; Lu, Yong-Long; Zheng, Xiao-Qi; Ritchie, R J

    2015-07-01

    The toxic effects of the ubiquitous pollutant 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) on the earthworm Eisenia fetida were assessed by determining growth-inhibition and gene transcript levels of superoxide dismutase (SOD), catalase (CAT), glutathione transferase (GST), and transcriptional changes of the stress-response gene (heat-shock protein 70 [Hsp70]). Somatic growth and growth-inhibition rates in all BDE-47-treated groups were significantly different from those of the controls. The SOD gene transcripts were upregulated at all exposure doses and reached the maximum at the concentration of 400 mg/kg dry weight (dw) (3.84-fold, P < 0.01), which protected earthworms from oxidative stresses. However, downregulation of CAT and Hsp70 was present in all exposure doses and reached to the minimum at concentrations of 400 mg/kg dw (0.07-fold, P < 0.01 and 0.06-fold, P < 0.01, respectively). Upregulation of GST gene transcript level presented significant changes at concentrations of 10 (2.69-fold, P < 0.05) and 100 mg/kg dw (2.55-fold, P < 0.05). SOD maintained a dynamic balance to upregulate SOD expression to eliminate superoxide radicals in all dosage treatments, but downregulation of CAT decreased the ability to eliminate hydrogen peroxide. These changes could result in biochemical and physiological disturbances in earthworms. PMID:25600924

  1. Avoiding complications in patellofemoral surgery.

    PubMed

    Harrison, Ryan K; Magnussen, Robert A; Flanigan, David C

    2013-06-01

    The diagnosis and treatment of patellofemoral disorders can challenge even the experienced orthopedic surgeon. Differential diagnosis is broad and multiple anatomic abnormalities must be taken into account in order to manage care. The majority of patients with patellofemoral disorders can be treated successfully nonoperatively. When nonoperative management fails, and in the carefully selected patient, a variety of surgical options exist based on the anatomic pathology involved, but each brings its own potential for complication. We discuss several of the surgical treatment options that are available to the orthopedic surgeon for the treatment of patellofemoral disorders, including lateral retinacular release, medial soft-tissue reconstructive procedures, and bony procedures (including trochleoplasty and tibial tubercle osteotomy. We describe potential complications of each procedure and what the orthopedic surgeon can do to avoid them. PMID:23649160

  2. Autonomous hazard detection and avoidance

    NASA Technical Reports Server (NTRS)

    Pien, Homer

    1992-01-01

    During GFY 91, Draper Laboratory was awarded a task by NASA-JSC under contract number NAS9-18426 to study and evaluate the potential for achieving safe autonomous landings on Mars using an on-board autonomous hazard detection and avoidance (AHDA) system. This report describes the results of that study. The AHDA task had four objectives: to demonstrate, via a closed-loop simulation, the ability to autonomously select safe landing sites and the ability to maneuver to the selected site; to identify key issues in the development of AHDA systems; to produce strawman designs for AHDA sensors and algorithms; and to perform initial trade studies leading to better understanding of the effect of sensor/terrain/viewing parameters on AHDA algorithm performance. This report summarizes the progress made during the first year, with primary emphasis on describing the tools developed for simulating a closed-loop AHDA landing. Some cursory performance evaluation results are also presented.

  3. Faecal avoidance and selective foraging: do wild mice have the luxury to avoid faeces?

    PubMed

    Walsh, Patrick T; McCreless, Erin; Pedersen, Amy B

    2013-09-01

    Host-parasite interactions are a key determinant of the population dynamics of wild animals, and behaviours that reduce parasite transmission and infection may be important for improving host fitness. While antiparasite behaviours have been demonstrated in laboratory animals and domesticated ungulates, whether these behaviours operate in the wild is poorly understood. Therefore, examining antiparasite behaviours in natural populations is crucial for understanding their ecological significance. In this study, we examined whether two wild rodents (white-footed mice, Peromyscus leucopus, and deer mice, Peromyscus maniculatus), selectively foraged away from conspecific faeces or avoided faeces altogether, and whether faecal gastrointestinal parasite status affected their behaviour. We also tested whether wild mice, when nesting, avoided using material that had previously been used by healthy or parasite-infected conspecifics. Our results, in contrast to laboratory mouse studies, suggest that wild mice do not demonstrate faecal avoidance, selective foraging or selective use of nesting material; they preferred being near faeces and did not differentiate between faeces from parasitized and uninfected conspecifics. Behavioural avoidance to reduce parasite infection may still represent an important strategy; however, mice in our study population appeared to favour the opportunity to feed and nest over the risks of coming into contact with faecal-transmitted parasites. Furthermore, the presence of conspecific faeces may actually provide a positive cue of a good foraging or nesting location. Ultimately, balancing the trade-off of performing antiparasite behaviours to reduce infection with missing an important feeding or nesting opportunity may be very different for animals in the wild facing complex and stochastic environments. PMID:24027342

  4. Time dependence of controls to avoid voltage collapse

    Microsoft Academic Search

    L. S. Vargas; C. A. Canizares

    2001-01-01

    Summary form only given, as follows. In this paper, the effect of time dependence of control actions used to avoid voltage collapse, such as reactive power compensation and load shedding, is studied. A thorough justification of the phenomena under study is first presented with the help of a simple test system. The time dependence of the control actions is then

  5. Time dependence of controls to avoid voltage collapse

    Microsoft Academic Search

    Luis S. Vargas; Claudio A. Cańizares

    2000-01-01

    In this paper, the effect of time dependence of control actions used to avoid voltage collapse, such as reactive power compensation and load shedding, is studied. A thorough justification of the phenomena under study is first presented with the help of a simple test system. The time dependence of the control actions is then studied in a real voltage collapse

  6. Avoidance response of a terrestrial salamander (Ambystoma macrodactylum) to chemical alarm cues.

    PubMed

    Chivers, D P; Kiesecker, J M; Anderson, M T; Wildy, E L; Blaustein, A R

    1996-09-01

    Organisms from a wide variety of taxonomic groups possess chemical alarm cues that are important in mediating predator avoidance. However, little is known about the presence of such alarm cues in most amphibians, and in particular terrestrial salamanders. In this study we tested whether adult long-toed salamanders (Ambystoma macrodactylum) showed an avoidance response to stimuli from injured conspecifics. Avoidance of stimuli from injured conspecifics could represent avoidance of a chemical alarm cue or, alternatively, avoidance of a territorial pheromone or conspecific predator odor. Consequently, we also tested whether salamanders avoided stimuli from noninjured conspecifics. Salamanders avoided stimuli from injured but not from noninjured conspecifics. Therefore, we concluded that the response to injured conspecifics represents avoidance of a chemical alarm cue and not avoidance of a territorial pheromone or predator cue. This is the first clear demonstration of chemical alarm signaling by a terrestrial amphibian and the first report of chemical alarm signaling in an ambystomatid salamander. By avoiding an area containing stimuli from injured conspecifics, long-toed salamanders may lower their risk of predation by avoiding areas where predators are foraging. PMID:24226482

  7. Avoidance of aluminum by rainbow trout

    SciTech Connect

    Exley, C.

    2000-04-01

    Aluminum is the principal toxicant in fish in acid waters. The ability to avoid Al, particularly at low concentrations, would confer a considerable ecological advantage, but previous research into avoidance of Al has produced mixed results. The author used a cylindrical perspex tank, 150 cm in length, to study avoidance of Al by rainbow trout fry. The fish avoided Al, and their response was dependent on pH. Avoidance that was demonstrated at pHs of 5.00, 5.50, 5.50, and 5.75 was abolished at a pH of 6.00. Fry avoided very low Al concentrations being sensitive to [Al] > 1.00 {micro}mol L{sup {minus}1} at a pH of 5.00. This unequivocal demonstration of avoidance by rainbow trout fry of Al may have important implications for the ecology of indigenous fish populations in surface waters impacted by acidic deposition.

  8. Bioturbation of three endogeic earthworms - A. caliginosa, A. chlorotica and A. icterica - depending on organic matter location

    NASA Astrophysics Data System (ADS)

    Le Couteulx, Alexis; Wolf, Cédric; Pérčs, Guénola; Hallaire, Vincent

    2015-04-01

    Earthworms alter soil structure through their bioturbation activity: the creation of burrow paths and the production of casts in their burrows or at soil surface. Thus, they may alter some soil functionnal properties (e.g. hydraulic conductivity) and ecosystem services. In cultivated fields, earthworms are a key structuring process and play a major role in the maintenance, the improvement and even the degradation of soil structure. However, bioturbation patterns of the different endogeic species are still not precisely known. This study aims at describing the burrowing and casting activity of three endogeic earthworm species with two different organic matter (OM) locations. Cylindrical microcosms (15 cm high) were set up with a silt-loam soil and 0.6 per cent of dry grass leaves was added at two locations: mixed with soil or dropped at its surface; three endogeic species were studied in monospecific microcosms: Allolobophora chlorotica, Allolobophora icterica and Aporrectodea caliginosa. Microcosms were kept for 60 days at 12°C. They were then stripped centimeter by centimeter and, on each layer the bioturbated area, number of bioturbated areas (= objects), blocking cast area (casts that prevent earthworms from passing), non-blocking cast area and the angles of burrow paths were assessed. In this study, the rate of non-blocking cast is stable whatever the species and the OM location. Regardless of the species, there are fewer objects but a greater percentage of blocking cast with mixed OM than with surface OM. Only A. chlorotica and A. caliginosa have a greater bioturbated area with mixed OM than with surface OM. With OM at soil surface: A. icterica has a higher bioturbated area and generates more objects than A. caliginosa, which has a higher bioturbated area and generates more objects than A. chlorotica. Interestingly, there are very few differences between the three species with mixed OM. The bioturbation activity of earthworms is also affected by depth: the bioturbation activity of A. chlorotica is mainly into the first three centimeters with mixed OM whereas it linearly decreases with surface OM. With both OM locations, the bioturbated area of A. icterica linearly increases with depth. To conclude, the acquired knowledges have been integrated in a model of soil structure simulation.

  9. Bioaccumulation of PCDD/Fs, PCBs and PBDEs by earthworms in field soils of an E-waste dismantling area in China.

    PubMed

    Shang, Hongtao; Wang, Pu; Wang, Thanh; Wang, Yawei; Zhang, Haidong; Fu, Jianjie; Ren, Daiwei; Chen, Weihai; Zhang, Qinghua; Jiang, Guibin

    2013-04-01

    A total of 60 paired samples of earthworm, corresponding soil and wormcast were collected to investigate the bioaccumulation tendency of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in earthworms from a typical E-waste dismantling area in east China. Significant correlations were observed for the total concentrations among different matrix types except for PCDD/Fs in soil and earthworm. The bioaccumulation tendency showed some differences among the contaminants. Calculated biota-soil accumulation factors (BSAFs) indicated that PCBs and PBDEs had higher bioaccumulation potential compared to PCDD/Fs, which was somewhat different from laboratory studies. The plot of mean BSAFs versus log Kow values for PCBs and PBDEs was well fitted by a second-order polynomial with the maximum BSAF at approximately log Kow of 6.5. While for PCDD/Fs, only a slightly decreasing trend was observed with increasing log Kow. Composition analysis indicated that tetra-, penta- and hexa-halogenated homologs had higher bioaccumulation levels, indicating that medium-halogenated congeners with log Kow around 6.5 are more easily accumulated by earthworms. Furthermore, the ratios of BDE-47/-99 and BDE-99/-100 showed some discrepancies with the technical products and other biotic species, suggesting different bioaccumulation potential of PBDEs in earthworm. PMID:23416248

  10. Is Avoiding an Aversive Outcome Rewarding? Neural Substrates of Avoidance Learning in the Human Brain

    Microsoft Academic Search

    Hackjin Kim; Shinsuke Shimojo; John P ODoherty

    2006-01-01

    Avoidance learning poses a challenge for reinforcement-based theories of instrumental conditioning, because once an aversive outcome is successfully avoided an individual may no longer experience extrinsic reinforcement for their behavior. One possible account for this is to propose that avoiding an aversive outcome is in itself a reward, and thus avoidance behavior is positively reinforced on each trial when the

  11. Bioaccumulation of Zn and Ag Nanoparticles in the Earthworms (Eisenia fetida)

    NASA Astrophysics Data System (ADS)

    Ha, Lee Seung; Sung-Dae, Kim; Yi, Yang Song; Byeong-Gweon, Lee

    2014-05-01

    Many studies are carried out to evaluate environmental effects of engineered nanoparticles (ENPs). Most of the previous studies primarily focused on the effects of nanoparticles into the aquatic environment and human. Model studies predict that ENPs released into environment would transferred primarily to the soil of the terrestrial environment. Despite this prediction, biogeochemical behavior of ENPs in soil environment as well as bioavailability of ENPs to soil-dwelling organisms such as earthworm, springtail, isopod and nematodes are poorly understood. The main goal of this study was to compare the bioaccumulation factor (BAFs) and subcellular partitioning of nanoparticles in the soil-dwelling earthworm (Eisenia fetida) from ENP (ZnO and Ag nanoparticles) or ionic metal (Zn2+, Ag+) contaminated soil. And the sequential extraction was also used to determine the mobility of metals in soil which could be used as to predict bioavailability and compare that with bioaccumulation factor. The radiotracer method was employed to trace the transfer of ENPs and ionic metal among different environmental media and animals. Radiolabeled 65ZnO, 110mAgNPs coated with PVP or citrate were synthesized in the laboratory and their chemical and biological behavior was compared to ionic 65Zn and 110mAg. The BAFs of Zn and Ag in the earthworms were determined after animals exposed to the contaminated soils. After the 7 days of elimination phase, subcellular partitioning of metals were also obtained. BAF for ZnO(0.06) was 31 times lower than that for Zn ion (1.86), suggesting that ZnO was less bioavailable than its ionic form from contaminated soil. On the other hands, BAFs for AgNPs coated with PVP (0.12) or with citrate (0.11) were comparable to those for Ag ion (0.17), indicating that Ag from contaminated soil was bioavailable in a similar rate regardless of chemical forms. The subcellular partitioning results showed that bioaccumulated Zn from Zn ion and ZnO contaminated soil were present mainly in HSP (heat-sensitive protein) while cellullar Ag from Ag ion and AgNPs (Ag/PVP, Ag/citrate) treatments were found mostly in cellular debris. No statistical difference in partitioning of metals among different subcelluar pools was found between the metal forms. Zn from ZnO contaminated solis was found largely in carbonate fraction (41%), while Zn from Zn ion treatment was found in Fe-Mn Oxide (29%). Association of Zn to mobile fractions (ZnO; 65%, Zn ion; 35%) suggest that Zn from ZnO contaminated soil would be more bioavailable than that from Zn ion treatment. However, the BAFs for Zn in the animals did not follow this prediction. Majority of Ag from AgNPs or Ag ion contaminated soil was bound mainly to biologically inert fractions mainly in organic matter, surphide fractions, and residual fractions. Consistent with these findings, the BAFs of Ag in the worms exposed to Ag contaminated soils were generally lower than those for Zn treatments.

  12. FVIII inhibitors: pathogenesis and avoidance

    PubMed Central

    2015-01-01

    The pathogenesis of inhibitory antibodies has been the focus of major scientific interest over the last decades, and several studies on underlying immune mechanisms and risk factors for formation of these antibodies have been performed with the aim of improving the ability to both predict and prevent their appearance. It seems clear that the decisive factors for the immune response to the deficient factor are multiple and involve components of both a constitutional and therapy-related nature. A scientific concern and obstacle for research in the area of hemophilia is the relatively small cohorts available for studies and the resulting risk of confounded and biased results. Careful interpretation of data is recommended to avoid treatment decisions based on a weak scientific platform. This review will summarize current concepts of the underlying immunological mechanisms and risk factors for development of inhibitory antibodies in patients with hemophilia A and discuss how these findings may be interpreted and influence our clinical management of patients. PMID:25712994

  13. FVIII inhibitors: pathogenesis and avoidance.

    PubMed

    Astermark, Jan

    2015-03-26

    The pathogenesis of inhibitory antibodies has been the focus of major scientific interest over the last decades, and several studies on underlying immune mechanisms and risk factors for formation of these antibodies have been performed with the aim of improving the ability to both predict and prevent their appearance. It seems clear that the decisive factors for the immune response to the deficient factor are multiple and involve components of both a constitutional and therapy-related nature. A scientific concern and obstacle for research in the area of hemophilia is the relatively small cohorts available for studies and the resulting risk of confounded and biased results. Careful interpretation of data is recommended to avoid treatment decisions based on a weak scientific platform. This review will summarize current concepts of the underlying immunological mechanisms and risk factors for development of inhibitory antibodies in patients with hemophilia A and discuss how these findings may be interpreted and influence our clinical management of patients. PMID:25712994

  14. Obstacle avoidance sonar for submarines

    NASA Astrophysics Data System (ADS)

    Dugas, Albert C.; Webman, Kenneth M.

    2002-05-01

    The Advanced Mine Detection Sonar (AMDS) system was designed to operate in poor environments with high biological and/or shallow-water boundary conditions. It provides increased capability for active detection of volume, close-tethered, and bottom mines, as well as submarine and surface target active/passive detection for ASW and collision avoidance. It also provides bottom topography mapping capability for precise submarine navigation in uncharted littoral waters. It accomplishes this by using advanced processing techniques with extremely narrow beamwidths. The receive array consists of 36 modules arranged in a 15-ft-diameter semicircle at the bottom of the submarine sonar dome to form a chin-mounted array. Each module consists of 40 piezoelectric rubber elements. The modules provide the necessary signal conditioning to the element data prior to signal transmission (uplink) through the hull. The elements are amplified, filtered, converted to digital signals by an A/D converter, and multiplexed prior to uplink to the inboard receiver. Each module also has a downlink over which it receives synchronization and mode/gain control. Uplink and downlink transmission is done using fiberoptic telemetry. AMDS was installed on the USS Asheville. The high-frequency chin array for Virginia class submarines is based on the Asheville design.

  15. Avoiding Loopholes with Hybrid Bell-Leggett-Garg Inequalities

    NASA Astrophysics Data System (ADS)

    Dressel, Justin; Korotkov, Alexander

    2014-03-01

    By combining the postulates of macrorealism with Bell-locality, we derive a qualitatively different hybrid inequality that avoids two loopholes that commonly appear in Leggett-Garg and Bell inequalities. First, locally-invasive measurements can be used, which avoids the ``clumsiness'' Leggett-Garg inequality loophole. Second, a single experimental ensemble with fixed analyzer settings is sampled, which avoids the ``disjoint sampling'' Bell inequality loophole. The derived hybrid inequality has the same form as the Clauser-Horne-Shimony-Holt Bell inequality; however, its quantum violation intriguingly requires weak measurements. A realistic explanation of an observed violation requires either the failure of Bell-locality, or a preparation-conspiracy of finely tuned and nonlocally-correlated noise. Modern superconducting and optical implementations of this test are considered.

  16. Avoiding loopholes with hybrid Bell-Leggett-Garg inequalities

    NASA Astrophysics Data System (ADS)

    Dressel, Justin; Korotkov, Alexander N.

    2014-01-01

    By combining the postulates of macrorealism with Bell locality, we derive a qualitatively different hybrid inequality that avoids two loopholes that commonly appear in Leggett-Garg and Bell inequalities. First, locally invasive measurements can be used, which avoids the "clumsiness" Leggett-Garg inequality loophole. Second, a single experimental ensemble with fixed analyzer settings is sampled, which avoids the "disjoint sampling" Bell inequality loophole. The derived hybrid inequality has the same form as the Clauser-Horne-Shimony-Holt Bell inequality; however, its quantum violation intriguingly requires weak measurements. A realistic explanation of an observed violation requires either the failure of Bell locality or a preparation conspiracy of finely tuned and nonlocally correlated noise. Modern superconducting and optical systems are poised to implement this test.

  17. Combining µXANES and µXRD mapping to analyse the heterogeneity in calcium carbonate granules excreted by the earthworm Lumbricus terrestris

    PubMed Central

    Brinza, Loredana; Schofield, Paul F.; Hodson, Mark E.; Weller, Sophie; Ignatyev, Konstantin; Geraki, Kalotina; Quinn, Paul D.; Mosselmans, J. Frederick W.

    2014-01-01

    The use of fluorescence full spectral micro-X-ray absorption near-edge structure (µXANES) mapping is becoming more widespread in the hard energy regime. This experimental method using the Ca K-edge combined with micro-X-ray diffraction (µXRD) mapping of the same sample has been enabled on beamline I18 at Diamond Light Source. This combined approach has been used to probe both long- and short-range order in calcium carbonate granules produced by the earthworm Lumbricus terrestris. In granules produced by earthworms cultured in a control artificial soil, calcite and vaterite are observed in the granules. However, granules produced by earthworms cultivated in the same artificial soil amended with 500?p.p.m. Mg also contain an aragonite. The two techniques, µXRD and µXANES, probe different sample volumes but there is good agreement in the phase maps produced. PMID:24365942

  18. The Role of Amygdala Nuclei in the Expression of Auditory Signaled Two-Way Active Avoidance in Rats

    ERIC Educational Resources Information Center

    Choi, June-Seek; Cain, Christopher K.; LeDoux, Joseph E.

    2010-01-01

    Using a two-way signaled active avoidance (2-AA) learning procedure, where rats were trained in a shuttle box to avoid a footshock signaled by an auditory stimulus, we tested the contributions of the lateral (LA), basal (B), and central (CE) nuclei of the amygdala to the expression of instrumental active avoidance conditioned responses (CRs).…

  19. Monocystis metaphirae sp. nov. (Protista: Apicomplexa: Monocystidae) from the earthworm Metaphire houlleti (Perrier).

    PubMed

    Bandyopadhyay, Probir K; Mallik, Partha; Göçmen, Bayram; Mitra, Amlan Kumar

    2006-01-01

    Biodiversity studies in search of endoparasitic acephaline gregarines revealed a new species of the genus Monocystis Stein, 1848 in the seminal vesicles of the earthworm Metaphire houlleti (Perrier) residing in alluvial soil of the district of North 24 Parganas. The new species is characterized by having bean-shaped gamonts measuring 94.0-151.0 (119.0+/-16.0) microm x 53.0-81.0(66.0+/-8.0) microm. The anterior end of the gamont is always wider than the posterior end. The mucron is always present at the wider end. The occurrence of syzygy (end to end, cauda-frontal) is a very rare feature which has been observed in the life cycle of the new species. The gametocyst is ovoid consisting of two unequal gamonts, measuring 85.0-102.0 microm (93.0+/-6.0). Oocysts are navicular in shape, measuring 6.5-11.0 (9.0+/-1.1) microm x 4.0-7.5 (5.5+/-1.9) microm. PMID:17106857

  20. Effects of pentachlorophenol on survival of earthworms (Lumbricus terrestris) and phagocytosis by their immunoactive coelomocytes

    SciTech Connect

    Giggleman, M.A.; Fitzpatrick, L.C.; Goven, A.J. [Univ. of North Texas, Denton, TX (United States); Venables, B.J. [TRAC Labs., Denton, TX (United States)

    1998-12-01

    Earthworms, Lumbricus terrestris, exposed for 96 h to filter paper saturated with five nominal concentrations of pentachlorophenol, exhibited a 50% lethal concentration (LC50) of 25.0 {micro}g PCP/cm{sup 2} and corresponding whole worm body burden-based 50% lethal dose (LD50) of 877.7 {micro}g PCP/g dry mass. Linear regression modeling showed that worms increased body concentrations (BC = {micro}g PCP/g dry tissue mass) with increasing exposure concentrations (EC) according to BC = 113.5 + 29.5EC. Phagocytosis of yeast cells by immunoactive coelomocytes was suppressed only at body concentrations (863.3 {micro}g PCP/g dry mass) that approximated the calculated LD50 and overlapped those demonstrating lethality, indicating a sharp transition between sublethal and lethal toxicity. An exposure concentration of 15 {micro}g PCP/cm{sup 2} produced significant suppression of phagocytosis of yeast cells by immunoactive coelomocytes. However, the average measured body burden from this group approximated the estimated LD50, indicating a sharp toxic response slope. Exposure to 10 {micro}g PCP/cm{sup 2} with a corresponding body concentration of 501.3 {micro}g PCP/g dry mass did not affect phagocytosis. The importance of body burden data is emphasized.

  1. Avoiding Adolescent Pregnancy: A Longitudinal Analysis of African American Youth

    PubMed Central

    Kogan, Steven M.; Cho, Junhan; Allen, Kimberly; Lei, Man-Kit; Beach, Steven R. H.; Gibbons, Frederick X.; Simons, Leslie G.; Simons, Ronald L.; Brody, Gene H.

    2013-01-01

    Purpose The timing and social context of pregnancy have significant implications for the well-being of African American young people. Rarely, however, do studies focus on identifying the developmental processes associated with young people’s avoidance of pregnancy until after adolescence. Methods We tested hypotheses regarding the factors associated with delayed fertility (no experience of a pregnancy by age 19) among a sample of 889 African American youth recruited at age 11 and assessed longitudinally through age 19. We hypothesized that, during preadolescence (age 11), health-promoting environmental processes would be linked to nurturant-responsive parenting, which in turn would be linked to youths’ conventional future orientations and risky sexual behavior in midadolescence (age 16) and to pregnancy experience by late adolescence (age 19). Hypotheses were tested with logistic structural equation modeling. Results Our conceptual model fit the data well. We identified a cascade process whereby protective environments were associated with nurturant-responsive parenting, which was associated with youths’ conventional future orientations; conventional future orientations were associated with avoidance of sexual risk behaviors at age 16 and avoidance of pregnancy by age 19. We identified an additional direct effect between nurturant-responsive parenting and avoidance of risky sexual behavior. Conclusions The results suggest processes that may be targeted to facilitate delayed fertility among African American youth. PMID:23583506

  2. Influence of copper fungicide residues on occurrence of earthworms in avocado orchard soils

    Microsoft Academic Search

    Lukas Van Zwieten; Josh Rust; Tim Kingston; Graham Merrington; Steven Morris

    2004-01-01

    The compost worm Eisenia fetida was used to demonstrate the avoidance by worms of Cu contaminated soil. Soils were collected from two avocado orchards in north eastern New South Wales, Australia. In avoidance trials, worms preferred non-contaminated control soils, sourced from adjacent to the orchard or an OECD control soil, when Cu residues in the orchard soils reached 4–34 mg

  3. Avoiding a maneuvering aircraft with TCAS. [Traffic Alert and Collison Avoidance System

    NASA Technical Reports Server (NTRS)

    Chappell, Sheryl L.

    1989-01-01

    The present investigation was carried out in NASA's Man-Vehicle Systems Research Facility B 727 simulator because of the need for veridical aircraft response. Pilot performance was measured in testing TCAS II after an avoidance maneuver has been initiated. A proposed change to the system will cause the TCAS II to issue a subsequent maneuver. This maneuver may be an increase in climb or descent rate from 1500 to 2500 ft/min, or a change from a climb to a descent or a descent to a climb. Three questions were addressed: (1) can the pilot detect the change in the maneuver advisory, (2) can the pilot respond promptly and accurately to the new advisory, and (3) can the maneuver be performed in the normal operating envelope of the aircraft. The reaction times found in the study suggest that pilots are able to respond within the two seconds targeted by the TCAS logic. The pilot performance data were used to modify the TCAS II logic to reflect actual pilot performance. This will result in a safe and appropriate maneuver selection in the rare instance when the conflicting aircraft maneuvers, and by doing so invalidates the initial maneuver issued by the collision avoidance system.

  4. Social anxiety and cognitive expectancy of aversive outcome in avoidance conditioning

    Microsoft Academic Search

    Verena Ly; Karin Roelofs

    2009-01-01

    Fear conditioning studies have shown that social anxiety is associated with enhanced expectancy of aversive outcome. However, the relation between cognitive expectancy and social anxiety has never been tested in avoidance conditioning paradigms. We compared 48 low (LSA) and high socially anxious individuals (HSA) on subjective expectancy of aversive outcome during an avoidance conditioning task. Displays of neutral faces were

  5. Avoidance of aposematic prey in European tits (Paridae): learned or innate?

    E-print Network

    Kratochvíl, Lukas

    Avoidance of aposematic prey in European tits (Paridae): learned or innate? Alice Exnerova´,a Pavel with rather few unrelated model species. We compared the origin of avoidance in European species of tits (Paridae). First, we tested whether wild-caught birds (blue tits, great tits, crested tits, coal tits

  6. Continuous place avoidance task reveals differences in spatial navigation in male and female rats

    Microsoft Academic Search

    José M Cimadevilla; André A Fenton; Jan Bures

    2000-01-01

    A new place navigation test was used to estimate the spatial orientation abilities of male and female rats. Animals had to avoid a room frame defined area on a rotating arena, entering of which was punished by mild footshock, i.e. rats had to avoid the same place in the room but different parts of the floor, which was rotated through

  7. Morphology and AFLP markers suggest three Hordeum chilense ecotypes that differ in avoidance to rust fungi

    Microsoft Academic Search

    M. Carlota Vaz Patto; Aernoudt Aardse; Jaap Buntjer; Diego Rubiales; A. Martin; Rients E. Niks

    2001-01-01

    In Hordeum chilense Roem. & Schult., a high variation in the level of avoidance to infection of barley leaf rust (Puccinia hordei Otth) occurs. Probably resulting from the properties of the stomata, the rust germ tube overgrows stomata, and the infection process fails in an early stage. In the present study we tested the hypothesis that the avoidance character occurs

  8. The Developmental Dynamics of Task-Avoidant Behavior and Math Performance in Kindergarten and Elementary School

    ERIC Educational Resources Information Center

    Hirvonen, Riikka; Tolvanen, Asko; Aunola, Kaisa; Nurmi, Jari-Erik

    2012-01-01

    Besides cognitive factors, children's learning at school may be influenced by more dynamic phenomena, such as motivation and achievement-related task-avoidant behavior. The present study examined the developmental dynamics of task-avoidant behavior and math performance from kindergarten to Grade 4. A total of 225 children were tested for their…

  9. Directional collision avoidance in ad hoc networks

    Microsoft Academic Search

    Yu Wang; Jose Joaquin Garcia-luna-aceves

    2004-01-01

    This paper analyzes the performance of directional collision avoidance schemes, in which antenna systems are used to direct the transmission and reception of control and data packets in channel access protocols based on four-way handshakes to try to avoid collisions. The first analytical model to consider directional reception and the possible difference in gain between omni-directional and directional transmissions is

  10. UAV based collision avoidance radar sensor

    Microsoft Academic Search

    Young K. Kwag; C. H. Chung

    2007-01-01

    In this paper, the critical requirement for obstacle awareness and avoidance is assessed with the compliance of the equivalent level of safety regulation, and then the collision avoidance radar sensor system is presented with the key design parameters for the requirement of the smart unmanned aerial vehicle in low-altitude flight. Based on the assessment of various sensors, small-sized radar sensor

  11. Dynamic collision avoidance and constraint violation compensation

    Microsoft Academic Search

    F. M. L. Amirouche; C. W. Tung

    1995-01-01

    This paper uses concepts in multibody dynamics, together with a collision detection algorithm to study the dynamics of collision avoidance. Obstacle avoidance of a mechanical system in motion is expressed in terms of distances, relative velocities and relative accelerations between potentially colliding bodies. The generalized control forces (constraint forces) used to adjust the system dynamics are based on an n-timestep

  12. Integration of Planning and Reactive Obstacle Avoidance

    E-print Network

    Minguez, Javier

    Integration of Planning and Reactive Obstacle Avoidance in Autonomous Sensor-Based Navigation-based navigation system to safely drive vehicles in realistic scenarios. Three modules with the following avoidance and modeling module. The advantage of this navigation system is to achieve a robust

  13. DYNAMIC TIME WINDOWS: CONGESTION CONTROL AND AVOIDANCE

    E-print Network

    Faber, Ted

    DYNAMIC TIME WINDOWS: CONGESTION CONTROL AND AVOIDANCE IN HIGH SPEED NETWORKS by THEODORE V. FABER, Dune, ch. 1 This thesis describes the Dynamic Time Windows congestion control and avoidance system. This system is designed to mitigate the effects of network congestion on today's networks and the networks

  14. Chronic Worry as Avoidance of Arousal

    Microsoft Academic Search

    Louis B. Laguna; Lindsay S. Ham; Debra A. Hope; Christopher Bell

    2004-01-01

    Previous research suggests that worry is primarily a verbal-linguistic activity that may serve as a method of cognitive avoidance of fearful imagery. The purpose of the present study was to examine cognitive avoidance in high worriers (N=22) and low worriers (N=24) using psychophysiological measures and a modified dichotic listening task. The task involved presenting neutral words into an unattending ear

  15. Avoiding memory leaks in POSIX thread programming

    E-print Network

    Avoiding memory leaks in POSIX thread programming Tips for detecting and avoiding POSIX thread memory leaks Skill Level: Introductory Wei Dong Xie (xieweid@cn.ibm.com) IBM Systems Director Product is forgetting to join joinable threads, which can create memory leaks and cause extra work. In this tips

  16. Obstacle Avoidance Method Study of Electric Wheelchair

    Microsoft Academic Search

    Tian Zhihong; Xu Wenhui; Liu Xiuhong

    2009-01-01

    Analyzing the characteristics of various sensors, a method of detecting obstacle and avoiding obstacle used in electric wheelchair is presented based on the requirement of electric wheelchair obstacle avoidance. Transmitting circuit which is composed by 555 timing chip and receiving circuit which is utilized by LM393 are designed for measuring ultrasonic distance. Receiving program with ADuC842 which makes use of

  17. Details Of Collision-Avoidance Study

    NASA Technical Reports Server (NTRS)

    Chappell, Sheryl L.; Billings, Charles E.; Olsen, M. Christine; Scott, Barry C.; Tuttell, Robert J.; Kozon, Thomas E.

    1990-01-01

    Report provides background information on and detailed description of study of pilots' use of traffic-alert and collision-avoidance system (TCAS II) in simulated flights. Described in article, "Evaluation of an Aircraft-Collision-Avoidance System" (ARC-12367). Plans, forms, training narratives, scripts, questionnaires, and other information compiled.

  18. Lead and stable lead isotope ratios in soil, earthworms, and bones of American woodcock (Scolopax minor) from eastern Canada.

    PubMed

    Scheuhammer, Anton M; Bond, Della E; Burgess, Neil M; Rodrigue, Jean

    2003-11-01

    A study to discriminate among different possible sources of elevated Pb exposure for American woodcock (Scolopax minor) in eastern Canada is described. Undamaged wing bones excised from young-of-the-year woodcock collected from several locations in southern Ontario, southern Quebec, New Brunswick, and Nova Scotia, Canada, along with soil and earthworm (Aporrectodea tuberculata and Lumbricus rubellus) samples from the same sites, were analyzed for total Pb, and stable Pb isotopes. Ignoring six soil samples with high (> 60 microg/g) Pb concentration from the vicinity of Montreal (QC, Canada), the mean soil-Pb concentration for all sites combined was 19 microg/g (dry wt; n = 64), with a mean 206Pb:207Pb ratio of 1.19, values typical for uncontaminated rural soils in eastern North America. In earthworms, Pb concentrations ranged from 2.4 to 865 (microg/g [dry wt], mean = 24 microg/g). Concentrations of Pb in worms and soils were positively correlated (r = 0.71; p < 0.01), and 206Pb:207Pb ratios for worms and soils were also positively correlated (r = 0.54; p < 0.05). However, most young-of-the-year woodcock with high bone-Pb accumulation (> 20 microg/g) had 206Pb:207Pb ratios substantially different from worms and soils sampled from the same areas, even though woodcock feed extensively on soil invertebrates, especially earthworms. The range of 206Pb:207Pb ratios in wing bones of woodcock with elevated Pb exposure was not consistent with exposure to environmental Pb from past gasoline combustion nor Precambrian mining wastes but was consistent with ingestion of spent Pb shotgun pellets. PMID:14587896

  19. Involvement of the Iron Regulatory Protein from Eisenia andrei Earthworms in the Regulation of Cellular Iron Homeostasis

    PubMed Central

    Procházková, Petra; Škanta, František; Roubalová, Radka; Šilerová, Marcela; Dvo?ák, Ji?í; Bilej, Martin

    2014-01-01

    Iron homeostasis in cells is regulated by iron regulatory proteins (IRPs) that exist in different organisms. IRPs are cytosolic proteins that bind to iron-responsive elements (IREs) of the 5?- or 3?-untranslated regions (UTR) of mRNAs that encode many proteins involved in iron metabolism. In this study, we have cloned and described a new regulatory protein belonging to the family of IRPs from the earthworm Eisenia andrei (EaIRP). The earthworm IRE site in 5?-UTR of ferritin mRNA most likely folds into a secondary structure that differs from the conventional IRE structures of ferritin due to the absence of a typically unpaired cytosine that participates in protein binding. Prepared recombinant EaIRP and proteins from mammalian liver extracts are able to bind both mammalian and Eisenia IRE structures of ferritin mRNA, although the affinity of the rEaIRP/Eisenia IRE structure is rather low. This result suggests the possible contribution of a conventional IRE structure. When IRP is supplemented with a Fe-S cluster, it can function as a cytosolic aconitase. Cellular cytosolic and mitochondrial fractions, as well as recombinant EaIRP, exhibit aconitase activity that can be abolished by the action of oxygen radicals. The highest expression of EaIRP was detected in parts of the digestive tract. We can assume that earthworms may possess an IRE/IRP regulatory network as a potential mechanism for maintaining cellular iron homeostasis, although the aconitase function of EaIRP is most likely more relevant. PMID:25279857

  20. Approach-avoidance activation without anterior asymmetry

    PubMed Central

    Uusberg, Andero; Uibo, Helen; Tiimus, Riti; Sarapuu, Helena; Kreegipuu, Kairi; Allik, Jüri

    2014-01-01

    Occasionally, the expected effects of approach-avoidance motivation on anterior EEG alpha asymmetry fail to emerge, particularly in studies using affective picture stimuli. These null findings have been explained by insufficient motivational intensity of, and/or overshadowing interindividual variability within the responses to emotional pictures. These explanations were systematically tested using data from 70 students watching 5 types of affective pictures ranging from very pleasant to unpleasant. The stimulus categories reliably modulated self-reports as well as the amplitude of late positive potential, an ERP component reflecting orienting toward motivationally significant stimuli. The stimuli did not, however, induce expected asymmetry effects either for the sample or individual participants. Even while systematic stimulus-dependent individual differences emerged in self-reports as well as LPP amplitudes, the asymmetry variability was dominated by stimulus-independent interindividual variability. Taken together with previous findings, these results suggest that under some circumstances anterior asymmetry may not be an inevitable consequence of core affect. Instead, state asymmetry shifts may be overpowered by stable trait asymmetry differences and/or stimulus-independent yet situation-dependent interindividual variability, possibly caused by processes such as emotion regulation or anxious apprehension. PMID:24653710