Science.gov

Sample records for plant construction effects

  1. Effects of plant root on hydraulic performance of clogging process in subsurface flow constructed wetland

    NASA Astrophysics Data System (ADS)

    Hua, Guofen; Zhao, Zhongwei; Zeng, Yitao

    2013-04-01

    Subsurface flow constructed wetlands (SFCWs) have proven to be an efficient ecological technology for the treatment of various kinds of wastewaters. The clogging issue is the main operational problem, which limits its wide application. Clogging is a complicated process with physical (such as physical filtration), biogeochemical and plant-related processes. It was generally stated that suspended solids accumulation and biofilm play dominant roles response for clogging. However, the role of plants in SFCWs clogging remains unclear and debatable. In this paper, the performance of plants in the whole clogging process was addressed based on the lab-experiments between planted and unplanted system by measuring effective porosity, coefficient of permeability of the substrate within different operation periods. Furthermore, flow pattern and transport properties of the clogging process in the planted and unplanted wetland systems were evaluated by hydraulic performance (e.g. mean residence time, short-circuiting, volumetric efficiency, number of continuously stirred tank reactors, hydraulic efficiency factor, etc.) with salt tracer experiments. Plants played different roles in different clogging stage. In the earlier clogging stage, there were no obvious different effects on clogging process between planted and unplanted system. The effective porosity and coefficient of permeability slightly decreased within the planted system, which indicated that plant root restricted the flow of water when the pore spaces were lager. In the middle and later clogging stage, especially, in the later stage, the effective porosity and the coefficient of permeability increased considerably in the plant root zone. Furthermore, the longer retention times and higher hydraulic efficiency factors were gained in the planted system compared to that of unplanted, which implied that growing roots might open the new pore spaces in the substrate. The results are expected to be useful in the design of

  2. Nitrogen and COD Removal from Septic Tank Wastewater in Subsurface Flow Constructed Wetlands: Plants Effects.

    PubMed

    Collison, R S; Grismer, M E

    2015-11-01

    We evaluated subsurface flow (SSF) constructed wetland treatment performance with respect to organics (COD) and nitrogen (ammonium and nitrate) removal from domestic (septic tank) wastewater as affected by the presence of plants, substrate "rock" cation exchange capacity (CEC), laboratory versus field conditions and use of synthetic as compared to actual domestic wastewater. This article considers the effects of plants on constructed wetland treatment in the field. Each constructed wetland system was comprised of two beds (2.6 m long by 0.28 m wide and deep filled with ~18 mm crushed lava rock) separated by an aeration tank connected in series. The lava rock had a porosity of ~47% and a CEC of 4 meq/100 gm. One pair of constructed wetland systems was planted with cattails in May 2008, while an adjacent pair of systems remained un-planted. Collected septic tank or synthesized wastewater was allowed to gravity feed each constructed wetland system and effluent samples were regularly collected and tested for COD and nitrogen species during four time periods spanning November 2008 through June 2009. These effluent concentrations were tested for statistical differences at the 95% level for individual time periods as well as the overall 6-month period. Organics removal from domestic wastewater was 78.8% and 76.1% in the planted and un-planted constructed wetland systems, respectively, while ammonium removal was 94.5% and 90.2%, respectively. Similarly, organics removal from the synthetic wastewater of equivalent strength was 88.8% and 90.1% for planted and un-planted constructed wetland systems, respectively, while ammonium removal was 96.9% and 97.3%, respectively.

  3. [Construction of a landscaping-type wetland system for wastewater treatment construction of a landscaping-type wetland system for wastewater treatment and analysis of plant denitrifying effect].

    PubMed

    Chen, Ming-li; Wu, Xiao-fu; Chen, Yong-hua; Jiang, Li-juan; Ji, Zhi-hui; Ma, Qun

    2010-03-01

    A pilot landscaping-type wetland system for wastewater treatment was constructed by introduction of 15 selected ornamental plant species (including 4 terrestrial plant species). The pilot system consists of 2 sequenced treatment units and 12 sub-units, i.e., a primary treatment unit with 4 parallel cells and a secondary treatment unit with 8 subsurface flow cells. Designed experiments were conducted in the established system to investigate the characteristics of nitrogen accumulation in different plants and the contribution of plant nitrogen uptake to total nitrogen removal of the constructed wetland system. The result shows that the direct contribution by plant uptake to the total nitrogen removal is low, ca. 1%-3% within the nitrogen concentration range 37.5-55.6 mg/L in the influent. Plant uptake does not fully reflect the important role of the plant species in the constructed wetland system for wastewater treatment as the function of the plant should include further its interaction with microorganisms and wetland fillers by enhancing microbial activities and filler adsorption capacities. The plant denitrifying effect, defined as the difference in nitrogen removal rates between units with and without plants, has been used to represent the contribution in nitrogen removal due to presence of plant in the system. The plant denitrifying effect thus includes both the plant nitrogen uptake and the interaction effect of plant with microorganisms and wetland fillers, the later being found to account for more than 80% of the total nitrogen removal in the established treatment system.

  4. Effects of single and multiple applications of glyphosate or aminopyralid on simple constructed plant communities.

    PubMed

    Pfleeger, Thomas; Blakeley-Smith, Matthew; Lee, E Henry; King, George; Plocher, Milton; Olszyk, David

    2014-10-01

    To determine effects of multiple applications of herbicides on small constructed plant communities, Prunella vulgaris L.var. lanceolata Fern, Festuca roemeri (Pavlick) Alexeev, Clarkia amoena (Lehm.) Nels., and Cynosurus echinatus L. were grown together in small field plots. Plants were treated with glyphosate at target concentrations of 0 × , 0.01 × , 0.1 × , and 0.2× a field application rate (FAR) of 1122 g ha(-1) active ingredient (a.i.) for 3 yr in 1 location, and for 2 yr in a second location. Plants also were treated with aminopyralid at 0 × , 0.037 × , 0.136 × , and 0.5× FAR of 123 g ha(-1) a.i. for 2 yr in 2 locations. Plants received 1, 2, or 3 applications of each herbicide each year. Species and community responses depended on herbicide concentration and number of applications. With glyphosate, plant volume (modified formula for a cone) tended to decrease for all species (especially C. echinatus), and the decreases generally became larger with more applications. Plant communities exposed to the 2 greatest concentrations initially differed from controls but then appeared to recover. With aminopyralid, C. amoena was essentially eliminated from the communities, especially at the 2 greatest FARs, whereas the other 3 species tended to have significant increases in volume, especially at the 2 smallest FARs. With aminopyralid, increasing numbers of applications produced variable results, and the plant community volume never tended to recover.

  5. Effect of season, substrate composition, and plant growth on landfill leachate treatment in a constructed wetland

    SciTech Connect

    Surface, J.M. ); Peverly, J.H. . Dept. of Soil, Crops, and Atmospheric Sciences); Steenhuis, T.S. . Dept. of Agricultural and Biological Engineering); Sanford, W.E. )

    1991-01-01

    In 1989 the US, Geological Survey (USGS), in cooperation with Tompkins County, New York Departments of Planning and Solid Waste, began a 3-year study at a municipal solid-waste landfill near Ithaca, N.Y., to test the efficiency of leachate treatment by constructed wetlands and to examine the associated treatment processes. Specific objectives of the study were to examine: (1) Treatment efficiency as function of substrate composition and grain size, degree of plant growth, and seasonal changes in evapotranspiration rates and microbial activity; (2) effects of leachate and plant growth on the hydraulic characteristics of the substrate; and (3) chemical, biological, and physical processes by which nutrients, metals, and organic compounds are removed from leachate as it flows through the substrate. This report addresses the first two of these objectives and briefly discusses the third. It (1) describes the substrate plots, leachate-distribution system, sampling methods, and analytical procedures; and (2) presents results in terms of (a) percent removal rates of selected constituents between inflow- and outflow-sampling points, (b) seasonal effects on constituent-removal rates, and (c) effect of substrate composition on constituent removal and plant growth.

  6. Effect of season, substrate composition, and plant growth on landfill leachate treatment in a constructed wetland

    SciTech Connect

    Surface, J.M.; Peverly, J.H.; Steenhuis, T.S.; Sanford, W.E.

    1991-12-31

    In 1989 the US, Geological Survey (USGS), in cooperation with Tompkins County, New York Departments of Planning and Solid Waste, began a 3-year study at a municipal solid-waste landfill near Ithaca, N.Y., to test the efficiency of leachate treatment by constructed wetlands and to examine the associated treatment processes. Specific objectives of the study were to examine: (1) Treatment efficiency as function of substrate composition and grain size, degree of plant growth, and seasonal changes in evapotranspiration rates and microbial activity; (2) effects of leachate and plant growth on the hydraulic characteristics of the substrate; and (3) chemical, biological, and physical processes by which nutrients, metals, and organic compounds are removed from leachate as it flows through the substrate. This report addresses the first two of these objectives and briefly discusses the third. It (1) describes the substrate plots, leachate-distribution system, sampling methods, and analytical procedures; and (2) presents results in terms of (a) percent removal rates of selected constituents between inflow- and outflow-sampling points, (b) seasonal effects on constituent-removal rates, and (c) effect of substrate composition on constituent removal and plant growth.

  7. Effects of acidification on metal accumulation by aquatic plants and invertebrates. 1. Constructed wetlands

    SciTech Connect

    Albers, P.H.; Camardese, M.B. . Patuxent Wildlife Research Center)

    1993-06-01

    Compared were concentrations of Al,Cd,Ca,Cu,Fe,Hg,Pb,Mg,Mn,Ni,P, and Zn in water, plants and aquatic insects of three acidified (pH [approximately] 5.0) and three nonacidified (pH [approximately] 6.5) constructed wetlands. Concentrations of Zn in water and bur-reed (Sparganium americanum) were higher in acidified wetlands than in nonacidified wetlands. Floating nonrooted plants contained mean concentrations of Fe, Mg, and Mn that were higher than recommended maximum levels for poultry feed. The mean concentrations of all metals in insects were below recommended maximum levels for poultry feed and below levels that cause toxic effects in wild birds. Smaller than expected increases of metal concentrations in the water of acidified wetlands were probably due to limited mobilization of metals from the sediments and insignificant changes in sedimentation of aqueous metals. Calcium was lower in acidified than in nonacidified wetland water, but the Ca content of insects and bur-reed was not lower. Low concentrations of Ca in aquatic insects from both groups of wetlands indicated that calcium-rich crustaceans and mollusks are probably important to female waterfowl and their young during the spring, when invertebrates make up the majority of the diet. Although toxic effects from metal ingestion seem to be unlikely consequences of wetland acidification, the adverse effect of low pH on the occurrence of crustaceans and mollusks could threatened egg production and development of young.

  8. Effects and Effectiveness of Two RNAi Constructs for Resistance to Pepper golden mosaic virus in Nicotiana benthamiana Plants

    PubMed Central

    Medina-Hernández, Diana; Rivera-Bustamante, Rafael Francisco; Tenllado, Francisco; Holguín-Peña, Ramón Jaime

    2013-01-01

    ToChLPV and PepGMV are Begomoviruses that have adapted to a wide host range and are able to cause major diseases in agronomic crops. We analyzed the efficacy of induced resistance to PepGMV in Nicotiana benthamiana plants with two constructs: one construct with homologous sequences derived from PepGMV, and the other construct with heterologous sequences derived from ToChLPV. Plants protected with the heterologous construct showed an efficacy to decrease the severity of symptoms of 45%, while plants protected with the homologous construct showed an efficacy of 80%. Plants protected with the heterologous construct showed a reduction of incidence of 42.86%, while the reduction of incidence in plants protected with the homologous construct was 57.15%. The efficacy to decrease viral load was 95.6% in plants protected with the heterologous construct, and 99.56% in plants protected with the homologous construct. We found, in both constructs, up-regulated key components of the RNAi pathway. This demonstrates that the efficacy of the constructs was due to the activation of the gene silencing mechanism, and is reflected in the decrease of viral genome copies, as well as in recovery phenotype. We present evidence that both constructs are functional and can efficiently induce transient resistance against PepGMV infections. This observation guarantees a further exploration as a strategy to control complex Begomovirus diseases in the field. PMID:24287597

  9. EFFECTIVE REMOVAL OF TCE IN A LABORATORY MODEL OF A PRB CONSTRUCTED WITH PLANT MULCH

    EPA Science Inventory

    Ground water contaminated with TCE is commonly treated with a permeable reactive barrier (PRB) constructed with zero-valence iron. The cost of iron as the reactive matrix has driven a search for less costly alternatives, and composted plant mulch has been used as an alternative ...

  10. Effects of acidification on metal accumulation by aquatic plants and invertebrates. 1. Constructed wetlands

    USGS Publications Warehouse

    Albers, P.H.; Camardese, M.B.

    1993-01-01

    The pH of lake water is often inversely correlated with concentrations of trace metals in the water column. Concentrations of Al, Cd, Ca, Cu, Fe, Hg, Pb, Mg, Mn, Ni, P, and Zn were compared in water, plants, and aquatic insects from three acidified (pH 5.0) and three nonacidified (pH 6.5) constructed wetlands. Concentrations of Zn in water and bur-reed (Sparganium americanum) were higher in acidified wetlands than in nonacidified wetlands. Floating nonrooted plants contained mean concentrations of Fe, Mg, and Mn that were higher than recommended maximum levels for poultry feed. The mean concentrations of all metals in insects were below recommended maximum levels for poultry feed and below levels that cause toxic effects in wild birds. Smaller than expected increases of metal concentrations in the water of acidified wetlands were probably due to limited mobilization of metals from the sediments and insignificant changes in sedimentation of aqueous metals. Calcium was lower in acidified than in nonacidified wetland water, but the Ca content of insects and bur-reed was not lower. Low concentrations of Ca in aquatic insects from both groups of wetlands indicate that calcium-rich crustaceans and mollusks are probably important to female waterfowl and their young during the spring, when invertebrates make up the majority of the diet. Although toxic effects from metal ingestion seem to be unlikely consequences of wetland acidification, the adverse effect of low pH on the occurrence of crustaceans and mollusks could threaten egg production and development of young.

  11. Development of a constructed Willamette Valley plant community to determine non-target effects of herbicide drift on native plants

    EPA Science Inventory

    As part of its regulation of pesticides, the US Environmental Protection must consider potential environmental effects, including impacts to nontarget plants. Normally the risk assessment to determine these impacts requires simple, individual species, greenhouse, dose-response e...

  12. Power Plant Construction

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Stone & Webster Engineering Corporation utilized TAP-A, a COSMIC program originally developed as part of a NASA investigation into the potential of nuclear power for space launch vehicles. It is useful in nuclear power plant design to qualify safety-related equipment at the temperatures it would experience should an accident occur. The program is easy to use, produces accurate results, and is inexpensive to run.

  13. Effects of plant species on soil microbial processes and CH4 emission from constructed wetlands.

    PubMed

    Wang, Yanhua; Yang, Hao; Ye, Chun; Chen, Xia; Xie, Biao; Huang, Changchun; Zhang, Jixiang; Xu, Meina

    2013-03-01

    Methane (CH(4)) emission from constructed wetland has raised environmental concern. This study evaluated the influence of mono and polyculture constructed wetland and seasonal variation on CH(4) fluxes. Methane emission data showed large temporal variation ranging from 0 to 249.29 mg CH(4) m(-2) h(-1). Results indicated that the highest CH(4) flux was obtained in the polyculture system, planted with Phragmites australis, Zizania latifolia and Typha latifolia, reflecting polyculture system could stimulate CH(4) emission. FISH analysis showed the higher amount of methanotrophs in the profile of Z. latifolia in both mono and polyculture systems. The highest methanogens amount and relatively lower methanotrophs amount in the profile of polyculture system were obtained. The results support the characteristics of CH(4) fluxes. The polyculture constructed wetland has the higher potential of global warming. PMID:23291006

  14. Effect of plant harvesting on the performance of constructed wetlands during winter: radial oxygen loss and microbial characteristics.

    PubMed

    Wang, Qian; Xie, Huijun; Zhang, Jian; Liang, Shuang; Ngo, Huu Hao; Guo, Wenshan; Liu, Chen; Zhao, Congcong; Li, Hao

    2015-05-01

    The aboveground tissue of plants is important for providing roots with constant photosynthetic resources. However, the aboveground biomass is usually harvested before winter to maintain the permanent removal of nutrients. In this work, the effects of harvest on plants' involvement in oxygen input as well as in microbial abundance and activity were investigated in detail. Three series of constructed wetlands with integrated plants ("unharvested"), harvested plants ("harvested"), and fully cleared plants ("cleared") were set up. Better performance was found in the unharvested units, with the radial oxygen loss (ROL) rates ranging from 0.05 to 0.59 μmol O₂/h/plant, followed by the harvested units that had relatively lower ROL rates (0.01 to 0.52 μmol O₂/h/plant). The cleared units had the lowest removal efficiency, which had no rhizome resources from the plants. The microbial population and activity were highest in the unharvested units, followed by the harvested and cleared units. Results showed that bacterial abundances and enhanced microbial activity were ten times higher on root surfaces compared with sands. These results indicate that late autumn harvesting of the aboveground biomass exhibited negative effects on plant ROL as well as on the microbial population and activity during the following winter.

  15. Preliminary analysis of projected construction employment effects of building the defense waste processing facility at the Savannah River Plant

    SciTech Connect

    Garey, R.B.; Blair, L.M.; Craig, R.L.; Stevenson, W.

    1981-09-01

    This study estimates the probable effects of constructing the DWPF on the surrounding labor markets. Analyses are based on data from the local and regional labor markets, information from experts on local construction activities, information on the labor requirements of the Vogtle Power Plant (two nuclear reactors) being built by Georgia Power Company in Burke County, Georgia, and an econometric model of the construction labor market, based on several surveys of workers building three Tennessee Valley Authority nuclear power plants. The results of this study are reported in three parts. In Part I, completed in May 1980, we describe the 1979 (base year) employment levels within the local and regional labor markets surrounding SRP, from which most DWPF construction workers are likely to be drawn. In Part II, completed in June 1980, we define the four local sources of construction employment that will compete for craftsmen when DWPF is built. Also in Part II, most of the projected impacts of the DWPF reference immobilization alternative (one of several alternatives that may be chosen) are reported. Several construction schedules and labor demand scenarios for the reference alternative are considered. In Part III, completed in January 1981, most of the estimated impacts of the DWPF alternative referred to as the staged process alternative are reported. Several construction schedules and labor demand scenarios for this alternative are considered.

  16. Effects of plant roots on the hydraulic performance during the clogging process in mesocosm vertical flow constructed wetlands.

    PubMed

    Hua, G F; Zhao, Z W; Kong, J; Guo, R; Zeng, Y T; Zhao, L F; Zhu, Q D

    2014-11-01

    The aim of this study was to evaluate the effects of plant roots (Typha angustifolia roots) on the hydraulic performance during the clogging process from the perspective of time and space distributions in mesocosm vertical flow-constructed wetlands with coarse sand matrix. For this purpose, a pair of lab-scale experiments was conducted to compare planted and unplanted systems by measuring the effective porosity and hydraulic conductivity of the substrate within different operation periods. Furthermore, the flow pattern of the clogging process in the planted and unplanted wetland systems were evaluated by their hydraulic performance (e.g., mean residence time, short circuiting, volumetric efficiency, number of continuously stirred tank reactors, and hydraulic efficiency factor) in salt tracer experiments. The results showed that the flow conditions would change in different clogging stages, which indicated that plants played different roles related to time and space. In the early clogging stages, plant roots restricted the flow of water, while in the middle and later clogging stages, especially the later stage, growing roots opened new pore spaces in the substrate. The roots played an important role in affecting the hydraulic performance in the upper layer (0-30 cm) where the sand matrix had a larger root volume fraction. Finally, the causes of the controversy over plant roots' effects on clogging were discussed. The results helped further understand the effects of plant roots on hydraulic performance during the clogging process.

  17. Nitrous oxide emission from polyculture constructed wetlands: effect of plant species.

    PubMed

    Wang, Yanhua; Inamori, Ryuhei; Kong, Hainan; Xu, Kaiqin; Inamori, Yuhei; Kondo, Takashi; Zhang, Jixiang

    2008-03-01

    Loss of nitrogen from the soil-plant system has raised environmental concern. This study assessed the fluxes of nitrous oxide (N2O) in the subsurface flow constructed wetlands (CWs). To better understand the mechanism of N2O emission, spatial distribution of ammonia-oxidizing bacteria (AOB) in four kinds of wetlands soil were compared. N2O emission data showed large temporal and spatial variation ranging from -5.5 to 32.7 mg N2O m(-2) d(-1). The highest N2O emission occurred in the cell planted with Phragmites australis and Zizania latifolia. Whereas, the lower emission rate were obtained in the cell planted with P. australis and Typha latifolia. These revealed that Z. latifolia stimulated the N2O emission. Transportation of more organic matter and oxygen for AOB growth may be the reason. The study of AOB also supported this result, indicating that the root structure of Z. latifolia was favored by AOB for N2O formation.

  18. Nitrous oxide emission from polyculture constructed wetlands: effect of plant species.

    PubMed

    Wang, Yanhua; Inamori, Ryuhei; Kong, Hainan; Xu, Kaiqin; Inamori, Yuhei; Kondo, Takashi; Zhang, Jixiang

    2008-03-01

    Loss of nitrogen from the soil-plant system has raised environmental concern. This study assessed the fluxes of nitrous oxide (N2O) in the subsurface flow constructed wetlands (CWs). To better understand the mechanism of N2O emission, spatial distribution of ammonia-oxidizing bacteria (AOB) in four kinds of wetlands soil were compared. N2O emission data showed large temporal and spatial variation ranging from -5.5 to 32.7 mg N2O m(-2) d(-1). The highest N2O emission occurred in the cell planted with Phragmites australis and Zizania latifolia. Whereas, the lower emission rate were obtained in the cell planted with P. australis and Typha latifolia. These revealed that Z. latifolia stimulated the N2O emission. Transportation of more organic matter and oxygen for AOB growth may be the reason. The study of AOB also supported this result, indicating that the root structure of Z. latifolia was favored by AOB for N2O formation. PMID:17655987

  19. Effect of photosynthetically elevated pH on performance of surface flow-constructed wetland planted with Phragmites australis.

    PubMed

    Yin, Xiaole; Zhang, Jian; Hu, Zhen; Xie, Huijun; Guo, Wenshan; Wang, Qingsong; Ngo, Huu Hao; Liang, Shuang; Lu, Shaoyong; Wu, Weizhong

    2016-08-01

    Combination of emergent and submerged plants has been proved to be able to enhance pollutant removal efficiency of surface flow-constructed wetland (SFCW) during winter. However, intensive photosynthesis of submerged plants during summer would cause pH increase, which may have adverse effects on emergent plants. In this study, nitrogen transformation of lab-scale SFCW under pH gradient of 7.5, 8.5, 9.5 and 10.5 was systematically investigated. The results showed that total nitrogen (TN) removal efficiency decreased from 76.3 ± 0.04 to 51.8 ± 0.04 % when pH increased from 7.5 to 10.5, which was mainly attributed to plant assimilation decay and inhibition of microbe activities (i.e., nitrite-oxidizing bacteria and denitrifiers). Besides, the highest sediment adsorption in SFCW was observed at pH of 8.5. In general, the combination of submerged and emergent plants is feasible for most of the year, but precaution should be taken to mitigate the negative effect of high alkaline conditions when pH rises to above 8.5 in midsummer.

  20. Effect of different plant species on nutrient removal and rhizospheric microorganisms distribution in horizontal-flow constructed wetlands.

    PubMed

    Meng, Panpan; Hu, Wenrong; Pei, Haiyan; Hou, Qingjie; Ji, Yan

    2014-01-01

    Three macrophyte species, Phragmites australis, Arundo donax L., and Typha latifolia L. have been separately grown in a horizontal-flow (HF) constructed wetland (CW) fed with domestic wastewater to investigate effects of plant species on nutrient removal and rhizospheric microorganisms. All the three mesocosms have been in operation for eight months under the loading rates of 1.14 g Nm(-2) d(-1) and 0.014gP m(-2) d(-1). Appropriately 34-43% phosphorus (P) was removed in HF CWs, and no distinct difference was found among the plants. In the growing season, A. donax L. removed 31.19 gm(-2) of nitrogen (N), followed by P. australis (29.96 g m(-2)), both of which were significantly higher than T. latifolia L. (7.21 g m(-2). Depending on the species, plants absorbed 1.73-7.15% of the overall N, and 0.06-0.56% of the P input. At least 10 common dominant microorganisms were found in the rhizosphere of all the three plants, and 6 of the 10 kinds of bacteria had close relationship with denitrifying bacteria, implying that denitrifiers were dominant microorganism distributed in rhizosphere of wetland plants.

  1. Effects of single and multiple applications of glyphosate and aminopyralid on simple constructed plant communities

    EPA Science Inventory

    Plant tests required for the registration of pesticides are generally performed under controlled laboratory/greenhouse conditions using single exposures, and the results may or may not be relevant to protecting plant communities or ecosystems. We report results from a field test ...

  2. Effects of plant biomass on nitrogen transformation in subsurface-batch constructed wetlands: a stable isotope and mass balance assessment.

    PubMed

    Chen, Yi; Wen, Yue; Zhou, Qi; Vymazal, Jan

    2014-10-15

    Nitrate is commonly found in the influent of subsurface-batch constructed wetlands (SSB CWs) used for tertiary wastewater treatments. To understand the effects of plants and the litter on nitrate removal, as well as on nitrogen transformation in SSB CWs, six laboratory-scale SSB CW microcosms were set up in duplicate and were operated as batch systems with hydraulic residence time (HRT) of 5d. The presence of Typha latifolia enhanced nitrate removal in SSB CWs, and the N removed by plant uptake was mainly stored in aboveground biomass. Typha litter addition greatly improved nitrate removal in SSB CWs through continuous input of labile organic carbon, and calculated enrichment factors (ε) were between -12.1‰--13.9‰ from the nitrogen stable isotope analysis, suggesting that denitrification plays a dominant role in the N removal. Most significantly, simultaneous sulfur-based autotrophic and heterotrophic denitrification was observed in CWs. Finally, mass balance showed that denitrification, sedimentation burial and plant uptake respectively contributed 54%-94%, 1%-46% and 7.5%-14.3% to the N removal in CWs.

  3. Effects of plant biomass on nitrate removal and transformation of carbon sources in subsurface-flow constructed wetlands.

    PubMed

    Wen, Yue; Chen, Yi; Zheng, Nan; Yang, Dianhai; Zhou, Qi

    2010-10-01

    Denitrification is strongly dependent on carbon quantity and quality in most constructed wetlands (CWs). In this study, four batch CWs were designed, and were fed with nitrate-dominated water to investigate nitrate removal affected by plant and external cattail litter with or without alkali pretreatment. The results showed that the unit with plant and alkali-pretreated litter was more efficient in the initial stage whereas unit with plant and unpretreated litter was superior to other units in the middle and terminal stages. Plant accounted for less than 37% of the nitrate removal in biomass-up added CWs. The different nitrate removal rates were found to be greatly affected by the composition of the plant biomass as well as the quantity and quality of the available organic matters. It was also observed that plant biomass degradation over the period of this study resulted in various N species and concentrations in effluent.

  4. Construction of mismatched inverted repeat (IR) silencing vectors for maximizing IR stability and effective gene silencing in plants.

    PubMed

    Rey, M E Chrissie; Harmse, Johan; Taylor, Sarah H; Arbuthnot, Patrick; Weinberg, Marc S

    2015-01-01

    Inverted repeat (IR) RNA silencing vectors containing homologous fragments of target endogenous plant genes, or pathogen genes, are the most widely used vectors to either study the function of genes involved in biotic stress or silence pathogens to induce plant resistance, respectively. RNA silencing has been exploited to produce transgenic plants with resistance to viral pathogens via posttranscriptional gene silencing (PTGS). In some cases, this technology is difficult to apply due to the instability of IR constructs during cloning and plant transformation. We have therefore developed a robust method for the production of long IR vector constructs by introducing base pair mismatches in the form of cytosine to thymine mutations on the sense arm by exposure to sodium bisulfite prior to assembly of the IR. PMID:25740374

  5. Removal of antibiotics and antibiotic resistance genes from domestic sewage by constructed wetlands: Effect of flow configuration and plant species.

    PubMed

    Chen, Jun; Ying, Guang-Guo; Wei, Xiao-Dong; Liu, You-Sheng; Liu, Shuang-Shuang; Hu, Li-Xin; He, Liang-Ying; Chen, Zhi-Feng; Chen, Fan-Rong; Yang, Yong-Qiang

    2016-11-15

    This study aims to investigate the removal of antibiotics and antibiotic resistance genes (ARGs) in raw domestic wastewater by various mesocosm-scale constructed wetlands (CWs) with different flow configurations or plant species including the constructed wetland with or without plant. Six mesocosm-scale CWs with three flow types (surface flow, horizontal subsurface flow and vertical subsurface flow) and two plant species (Thaliadealbata Fraser and Iris tectorum Maxim) were set up in the outdoor. 8 antibiotics including erythromycin-H2O (ETM-H2O), monensin (MON), clarithromycin (CTM), leucomycin (LCM), sulfamethoxazole (SMX), trimethoprim (TMP), sulfamethazine (SMZ) and sulfapyridine (SPD) and 12 genes including three sulfonamide resistance genes (sul1, sul2 and sul3), four tetracycline resistance genes (tetG, tetM, tetO and tetX), two macrolide resistance genes (ermB and ermC), two chloramphenicol resistance genes (cmlA and floR) and 16S rRNA (bacteria) were determined in different matrices (water, particle, substrate and plant phases) from the mesocosm-scale systems. The aqueous removal efficiencies of total antibiotics ranged from 75.8 to 98.6%, while those of total ARGs varied between 63.9 and 84.0% by the mesocosm-scale CWs. The presence of plants was beneficial to the removal of pollutants, and the subsurface flow CWs had higher pollutant removal than the surface flow CWs, especially for antibiotics. According to the mass balance analysis, the masses of all detected antibiotics during the operation period were 247,000, 4920-10,600, 0.05-0.41 and 3500-60,000μg in influent, substrate, plant and effluent of the mesocosm-scale CWs. In the CWs, biodegradation, substrate adsorption and plant uptake all played certain roles in reducing the loadings of nutrients, antibiotics and ARGs, but biodegradation was the most important process in the removal of these pollutants. PMID:27443461

  6. Removal of antibiotics and antibiotic resistance genes from domestic sewage by constructed wetlands: Effect of flow configuration and plant species.

    PubMed

    Chen, Jun; Ying, Guang-Guo; Wei, Xiao-Dong; Liu, You-Sheng; Liu, Shuang-Shuang; Hu, Li-Xin; He, Liang-Ying; Chen, Zhi-Feng; Chen, Fan-Rong; Yang, Yong-Qiang

    2016-11-15

    This study aims to investigate the removal of antibiotics and antibiotic resistance genes (ARGs) in raw domestic wastewater by various mesocosm-scale constructed wetlands (CWs) with different flow configurations or plant species including the constructed wetland with or without plant. Six mesocosm-scale CWs with three flow types (surface flow, horizontal subsurface flow and vertical subsurface flow) and two plant species (Thaliadealbata Fraser and Iris tectorum Maxim) were set up in the outdoor. 8 antibiotics including erythromycin-H2O (ETM-H2O), monensin (MON), clarithromycin (CTM), leucomycin (LCM), sulfamethoxazole (SMX), trimethoprim (TMP), sulfamethazine (SMZ) and sulfapyridine (SPD) and 12 genes including three sulfonamide resistance genes (sul1, sul2 and sul3), four tetracycline resistance genes (tetG, tetM, tetO and tetX), two macrolide resistance genes (ermB and ermC), two chloramphenicol resistance genes (cmlA and floR) and 16S rRNA (bacteria) were determined in different matrices (water, particle, substrate and plant phases) from the mesocosm-scale systems. The aqueous removal efficiencies of total antibiotics ranged from 75.8 to 98.6%, while those of total ARGs varied between 63.9 and 84.0% by the mesocosm-scale CWs. The presence of plants was beneficial to the removal of pollutants, and the subsurface flow CWs had higher pollutant removal than the surface flow CWs, especially for antibiotics. According to the mass balance analysis, the masses of all detected antibiotics during the operation period were 247,000, 4920-10,600, 0.05-0.41 and 3500-60,000μg in influent, substrate, plant and effluent of the mesocosm-scale CWs. In the CWs, biodegradation, substrate adsorption and plant uptake all played certain roles in reducing the loadings of nutrients, antibiotics and ARGs, but biodegradation was the most important process in the removal of these pollutants.

  7. Effects of design flow and treatment level on construction and operation costs of municipal wastewater treatment plants and their implications on policy making.

    PubMed

    Friedler, Eran; Pisanty, Ehud

    2006-12-01

    Construction costs of 55 municipal wastewater treatment plants in Israel (secondary, advanced secondary, and advanced treatment) were analysed in order to derive cost functions expressing the effects of design flow and treatment level on construction costs. Three equations were derived (statistically significant, p<0.01), one for each treatment level. These indicate that economy of scale may become weaker as treatment level rises. Analysis of the distribution of construction costs revealed negative correlation (p<0.05) between the proportional cost of civil engineering and design flow, positive correlation (p<0.05) between the proportional cost of elecromechanical equipment and design flow, and no correlation between the proportional cost of electricity and control and design flow. Operation costs were found to be 20-70% more sensitive than construction costs to treatment level. The share of operation costs as part of the total annual costs was found to increase both with design flow and treatment level, whereas the share of construction costs concurrently decreased. The implication of the findings on policy, and consequently on treatment plants performance is discussed in the last part of the paper.

  8. Analysis of nuclear power plant construction costs

    SciTech Connect

    Not Available

    1986-01-01

    The objective of this report is to present the results of a statistical analysis of nuclear power plant construction costs and lead-times (where lead-time is defined as the duration of the construction period), using a sample of units that entered construction during the 1966-1977 period. For more than a decade, analysts have been attempting to understand the reasons for the divergence between predicted and actual construction costs and lead-times. More importantly, it is rapidly being recognized that the future of the nuclear power industry rests precariously on an improvement in the cost and lead-time situation. Thus, it is important to study the historical information on completed plants, not only to understand what has occurred to also to improve the ability to evaluate the economics of future plants. This requires an examination of the factors that have affected both the realized costs and lead-times and the expectations about these factors that have been formed during the construction process. 5 figs., 22 tabs.

  9. Modularization Technology in Power Plant Construction

    SciTech Connect

    Kenji Akagi; Kouichi Murayama; Miki Yoshida; Junichi Kawahata

    2002-07-01

    Since the early 1980's, Hitachi has been developing and applying modularization technology to domestic nuclear power plant construction, and has achieved great rationalization. Modularization is one of the plant construction techniques which enables us to reduce site labor by pre-assembling components like equipment, pipes, valves and platforms in congested areas and installing them using large capacity cranes for cost reduction, better quality, safety improvement and shortening of construction time. In this paper, Hitachi's modularization technologies are described especially from with respect to their sophisticated design capabilities. The application of 3D-CAD at the detailed layout design stage, concurrent design environment achieved by the computer network, module design quantity control and the management system are described. (authors)

  10. [Methods for construction of transgenic plant expression vector: a review].

    PubMed

    Zhang, Yangpu; Yang, Shushen

    2015-03-01

    Construction of recombinant plasmid vector for gene expression is a key step in making transgenic plants and important to study gene function and plant genetic engineering. A right choice of gene construction method can be cost-effective and achieve more diverse recombinant plasmids. In addition to the traditional methods in construction of plant gene expression vectors, such as Gateway technology, three DNA method and one step cloning, a few novel methods have been developed in recent years. These methods include oligonucleotide synthesis-based construction of small fragment gene expression vectors via competitive connection; construction of small RNA expression vector using pre-microRNA; recombination-fusion PCR method which inserts DNA fragments of multiple restriction sites into the target vector; and insertion of a DNA fragment into any region of a linear vector via In-Fusion Kit. Construction of complex vectors with many fragments uses sequence and ligation-independent cloning method, Gibson isothermal assembly or Golden Gate assembly. This paper summarizes our working experience in the area of recombinant vector construction and reports from others with an intention to disseminate ideas about currently widely used DNA recombination methods for plant transformation.

  11. Construction poses highest power plant fire threat

    SciTech Connect

    Not Available

    1980-03-01

    Power plants are more vulnerable to fire during the construction period than at any other time. Data gathered from fires at plant construction sites show that 65% result from cutting and welding activities and that the Control of combustible materials and work processes is the key factor. Contractors need to cooperate on cleanup and to upgrade the quality of temporary buildings on the site. Among the steps which could reduce fire risks are the early installation of water for fire hydrants and automatic sprinklers, testing of tarpaulins for flame retardency, the use of metal or fire retardant scaffolding and forms, approved temporary heating equipment, flushing turbine oil systems before startup, and the use of non-flammable water pipe tubing. Seven safety rules are outlined for welding and cutting procedures. (DCK)

  12. 38. Photocopy of photograph. STEEL PLANT, BOILERS UNDER CONSTRUCTION IN ...

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

    38. Photocopy of photograph. STEEL PLANT, BOILERS UNDER CONSTRUCTION IN BOILER PLANT LOCATED EAST OF MAIN STEEL PLANT, 1909. (From the Bethlehem Steel Corporation collection, Seattle, WA) - Irondale Iron & Steel Plant, Port Townsend, Jefferson County, WA

  13. 47 CFR 32.2003 - Telecommunications plant under construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Telecommunications plant under construction. 32... Accounts § 32.2003 Telecommunications plant under construction. (a) This account shall include the original... appropriate plant accounts the cost of any construction project which is estimated to be completed and...

  14. 47 CFR 32.2003 - Telecommunications plant under construction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Telecommunications plant under construction. 32... Accounts § 32.2003 Telecommunications plant under construction. (a) This account shall include the original... appropriate plant accounts the cost of any construction project which is estimated to be completed and...

  15. 47 CFR 32.2003 - Telecommunications plant under construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Telecommunications plant under construction. 32... Accounts § 32.2003 Telecommunications plant under construction. (a) This account shall include the original... appropriate plant accounts the cost of any construction project which is estimated to be completed and...

  16. 47 CFR 32.2003 - Telecommunications plant under construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Telecommunications plant under construction. 32... Accounts § 32.2003 Telecommunications plant under construction. (a) This account shall include the original... appropriate plant accounts the cost of any construction project which is estimated to be completed and...

  17. Effectiveness of Rice Agricultural Waste, Microbes and Wetland Plants in the Removal of Reactive Black-5 Azo Dye in Microcosm Constructed Wetlands.

    PubMed

    Saba, Beenish; Jabeen, Madeeha; Khalid, Azeem; Aziz, Irfan; Christy, Ann D

    2015-01-01

    Azo dyes are commonly generated as effluent pollutants by dye using industries, causing contamination of surface and ground water. Various strategies are employed to treat such wastewater; however, a multi-faceted treatment strategy could be more effective for complete removal of azo dyes from industrial effluent than any single treatment. In the present study, rice husk material was used as a substratum in two constructed wetlands (CWs) and augmented with microorganisms in the presence of wetland plants to effectively treat dye-polluted water. To evaluate the efficiency of each process the study was divided into three levels, i.e., adsorption of dye onto the substratum, phytoremediation within the CW and then bioremediation along with the previous two processes in the augmented CW. The adsorption process was helpful in removing 50% dye in presence of rice husk while 80% in presence of rice husk biocahr. Augmentation of microorganisms in CW systems has improved dye removal efficiency to 90%. Similarly presence of microorganisms enhanced removal of total nitrogen (68% 0 and Total phosphorus (75%). A significant improvement in plant growth was also observed by measuring plant height, number of leaves and leave area. These findings suggest the use of agricultural waste as part of a CW substratum can provide enhanced removal of textile dyes.

  18. Structures and construction of nuclear power plants on lunar surface

    NASA Astrophysics Data System (ADS)

    Shimizu, Katsunori; Kobatake, Masuhiko; Ogawa, Sachio; Kanamori, Hiroshi; Okada, Yasuhiko; Mano, Hideyuki; Takagi, Kenji

    1991-07-01

    The best structure and construction techniques of nuclear power plants in the severe environments on the lunar surface are studied. Facility construction types (functional conditions such as stable structure, shield thickness, maintainability, safety distances, and service life), construction conditions (such as construction methods, construction equipment, number of personnel, time required for construction, external power supply, and required transportation) and construction feasibility (construction method, reactor transportation between the moon and the earth, ground excavation for installation, loading and unloading, transportation, and installation, filling up the ground, electric power supply of plant S (300 kW class) and plant L (3000 kW class)) are outlined. Items to pay attention to in construction are (1) automation and robotization of construction; (2) cost reduction by multi functional robots; and (3) methods of supplying power to robots. A precast concrete block manufacturing plant is also outlined.

  19. 5. Photocopy of Historic Construction Photograph. PUMPING PLANT AND STILLING ...

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

    5. Photocopy of Historic Construction Photograph. PUMPING PLANT AND STILLING POND. (Original print, U. S. Bureau of Reclamation, Yakima, WA., ca. 1915) - Outlook Irrigation District, Pumping Plant & Woodstave Pipe, Hudson Road & Snipes Lateral Road vicinity, Outlook, Yakima County, WA

  20. 4. Photocopy of Historic Construction Photograph. PUMPING PLANT (Original print, ...

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

    4. Photocopy of Historic Construction Photograph. PUMPING PLANT (Original print, U.S. Bureau of Reclamation, Yakima, WA., ca. 1915) - Outlook Irrigation District, Pumping Plant & Woodstave Pipe, Hudson Road & Snipes Lateral Road vicinity, Outlook, Yakima County, WA

  1. 33. CONSTRUCTION OF FOUNDATION FOR ORIGINAL CROSSCUT DIESEL PLANT BUILDING, ...

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

    33. CONSTRUCTION OF FOUNDATION FOR ORIGINAL CROSSCUT DIESEL PLANT BUILDING, LATER ENLARGED TO HOUSE STEAM GENERATING EQUIPMENT. November 23, 1937 - Crosscut Steam Plant, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  2. 47 CFR 32.2003 - Telecommunications plant under construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Telecommunications plant under construction. 32.2003 Section 32.2003 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER... Accounts § 32.2003 Telecommunications plant under construction. (a) This account shall include the...

  3. 9. VIEW OF NEW PUMP PLANT CONSTRUCTION WORK, SHOWING PIPELINE ...

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

    9. VIEW OF NEW PUMP PLANT CONSTRUCTION WORK, SHOWING PIPELINE FORMS, April 24, 1952 - Highline Canal & Pumping Station, South side of Salt River between Tempe, Phoenix & Mesa, Tempe, Maricopa County, AZ

  4. 8. VIEW OF NEW PUMP PLANT CONSTRUCTION WORK, SHOWING STEEL ...

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

    8. VIEW OF NEW PUMP PLANT CONSTRUCTION WORK, SHOWING STEEL MANIFOLD RUNNING BELOW GRADE, April 24, 1952 - Highline Canal & Pumping Station, South side of Salt River between Tempe, Phoenix & Mesa, Tempe, Maricopa County, AZ

  5. Belowground advantages in construction cost facilitate a cryptic plant invasion.

    PubMed

    Caplan, Joshua S; Wheaton, Christine N; Mozdzer, Thomas J

    2014-04-30

    The energetic cost of plant organ construction is a functional trait that is useful for understanding carbon investment during growth (e.g. the resource acquisition vs. tissue longevity tradeoff), as well as in response to global change factors like elevated CO2 and N. Despite the enormous importance of roots and rhizomes in acquiring soil resources and responding to global change, construction costs have been studied almost exclusively in leaves. We sought to determine how construction costs of aboveground and belowground organs differed between native and introduced lineages of a geographically widely dispersed wetland plant species (Phragmites australis) under varying levels of CO2 and N. We grew plants under ambient and elevated atmospheric CO2, as well as under two levels of soil nitrogen. We determined construction costs for leaves, stems, rhizomes and roots, as well as for whole plants. Across all treatment conditions, the introduced lineage of Phragmites had a 4.3 % lower mean rhizome construction cost than the native. Whole-plant construction costs were also smaller for the introduced lineage, with the largest difference in sample means (3.3 %) occurring under ambient conditions. In having lower rhizome and plant-scale construction costs, the introduced lineage can recoup its investment in tissue construction more quickly, enabling it to generate additional biomass with the same energetic investment. Our results suggest that introduced Phragmites has had an advantageous tissue investment strategy under historic CO2 and N levels, which has facilitated key rhizome processes, such as clonal spread. We recommend that construction costs for multiple organ types be included in future studies of plant carbon economy, especially those investigating global change.

  6. 13. WEST SIDE OF CROSSCUT DIESEL PLANT UNDER CONSTRUCTION FOR ...

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

    13. WEST SIDE OF CROSSCUT DIESEL PLANT UNDER CONSTRUCTION FOR EXPANSION TO HOUSE STEAM UNITS, SHOWING STRUCTURAL STEEL AND STEAM BOILERS NOS. 1, 2, AND 3 BEING INSTALLED. March 15, 1941 - Crosscut Steam Plant, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  7. 11. VIEW FROM SOUTH OF CROSSCUT DIESEL PLANT UNDER CONSTRUCTION ...

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

    11. VIEW FROM SOUTH OF CROSSCUT DIESEL PLANT UNDER CONSTRUCTION FOR EXPANSION TO HOUSE STEAM UNITS, SHOWING ORIGINAL FUEL TANK (FAR LEFT) AND DIESEL COOLING TOWER (CENTER). March 15, 1941 - Crosscut Steam Plant, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  8. ITER Construction--Plant System Integration

    SciTech Connect

    Tada, E.; Matsuda, S.

    2009-02-19

    This brief paper introduces how the ITER will be built in the international collaboration. The ITER Organization plays a central role in constructing ITER and leading it into operation. Since most of the ITER components are to be provided in-kind from the member countries, integral project management should be scoped in advance of real work. Those include design, procurement, system assembly, testing, licensing and commissioning of ITER.

  9. The effectiveness of power-generating complexes constructed on the basis of nuclear power plants combined with additional sources of energy determined taking risk factors into account

    NASA Astrophysics Data System (ADS)

    Aminov, R. Z.; Khrustalev, V. A.; Portyankin, A. V.

    2015-02-01

    The effectiveness of combining nuclear power plants equipped with water-cooled water-moderated power-generating reactors (VVER) with other sources of energy within unified power-generating complexes is analyzed. The use of such power-generating complexes makes it possible to achieve the necessary load pickup capability and flexibility in performing the mandatory selective primary and emergency control of load, as well as participation in passing the night minimums of electric load curves while retaining high values of the capacity utilization factor of the entire power-generating complex at higher levels of the steam-turbine part efficiency. Versions involving combined use of nuclear power plants with hydrogen toppings and gas turbine units for generating electricity are considered. In view of the fact that hydrogen is an unsafe energy carrier, the use of which introduces additional elements of risk, a procedure for evaluating these risks under different conditions of implementing the fuel-and-hydrogen cycle at nuclear power plants is proposed. Risk accounting technique with the use of statistical data is considered, including the characteristics of hydrogen and gas pipelines, and the process pipelines equipment tightness loss occurrence rate. The expected intensities of fires and explosions at nuclear power plants fitted with hydrogen toppings and gas turbine units are calculated. In estimating the damage inflicted by events (fires and explosions) occurred in nuclear power plant turbine buildings, the US statistical data were used. Conservative scenarios of fires and explosions of hydrogen-air mixtures in nuclear power plant turbine buildings are presented. Results from calculations of the introduced annual risk to the attained net annual profit ratio in commensurable versions are given. This ratio can be used in selecting projects characterized by the most technically attainable and socially acceptable safety.

  10. 17. Mormon Flat power plant under construction. Notice location of ...

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

    17. Mormon Flat power plant under construction. Notice location of spillway gates. Needle valves at lower left are for bypass. Photographer unknown, March 1926. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

  11. Analysis of conservative tracer measurement results using the Frechet distribution at planted horizontal subsurface flow constructed wetlands filled with coarse gravel and showing the effect of clogging processes.

    PubMed

    Dittrich, Ernő; Klincsik, Mihály

    2015-11-01

    A mathematical process, developed in Maple environment, has been successful in decreasing the error of measurement results and in the precise calculation of the moments of corrected tracer functions. It was proved that with this process, the measured tracer results of horizontal subsurface flow constructed wetlands filled with coarse gravel (HSFCW-C) can be fitted more accurately than with the conventionally used distribution functions (Gaussian, Lognormal, Fick (Inverse Gaussian) and Gamma). This statement is true only for the planted HSFCW-Cs. The analysis of unplanted HSFCW-Cs needs more research. The result of the analysis shows that the conventional solutions (completely stirred series tank reactor (CSTR) model and convection-dispersion transport (CDT) model) cannot describe these types of transport processes with sufficient accuracy. These outcomes can help in developing better process descriptions of very difficult transport processes in HSFCW-Cs. Furthermore, a new mathematical process can be developed for the calculation of real hydraulic residence time (HRT) and dispersion coefficient values. The presented method can be generalized to other kinds of hydraulic environments.

  12. [Risk communication in construction of new nuclear power plant].

    PubMed

    He, Gui-Zhen; Lü, Yong-Long

    2013-03-01

    Accompanied by construction of new nuclear power plants in the coming decades in China, risk management has become increasingly politicized and contentious. Nuclear risk communication is a critical component in helping individuals prepare for, respond to, and recover from nuclear power emergencies. It was discussed that awareness of trust and public attitudes are important determinants in nuclear power risk communication and management. However, there is limited knowledge about how to best communicate with at-risk populations around nuclear power plant in China. To bridge this gap, this study presented the attitudinal data from a field survey in under-building Haiyang nuclear power plant, Shandong Province to measure public support for and opposition to the local construction of nuclear power plant. The paper discussed the structure of the communication process from a descriptive point of view, recognizing the importance of trust and understanding the information openness. The results showed that decision-making on nuclear power was dominated by a closed "iron nuclear triangle" of national governmental agencies, state-owned nuclear enterprises and scientific experts. Public participation and public access to information on nuclear constructions and assessments have been marginal and media was a key information source. As information on nuclear power and related risks is very restricted in China, Chinese citizens (51%) tend to choose the government as the most trustworthy source. More respondents took the negative attitudes toward nuclear power plant construction around home. It drew on studies about risk communication to develop some guidelines for successful risk communication. The conclusions have vast implications for how we approach risk management in the future. The findings should be of interest to state and local emergency managers, community-based organizations, public health researchers, and policy makers.

  13. Construction of Simulation Model for OTEC Plant Using Uehara Cycle

    NASA Astrophysics Data System (ADS)

    Goto, Satoru; Motoshima, Yoshiki; Sugi, Takenao; Yasunaga, Takeshi; Ikegami, Yasuyuki; Nakamura, Masatoshi

    Ocean Thermal Energy Conversion (OTEC) converts heat energy into electricity using 20-27[°C] temperature difference between warm seawater at surface and cold seawater in depth. In this paper, a simulation model for an OTEC plant, which uses the Uehara cycle with an ammonia-water mixture as working fluid, is constructed based on the mass balance and the heat balance. Moreover, a method of the initial value determination for numerical simulation is developed. Accuracy of the simulation model was evaluated by comparing with the experimental results of a pilot OTEC plant.

  14. The effect of public or private structures in wastewater treatment on the conditions for the design, construction and operation of wastewater treatment plants.

    PubMed

    Grünebaum, T; Bode, H

    2004-01-01

    Organised in public or private structures, wastewater services have to cope with different framework conditions as regards planning, construction, financing and operation. This leads quite often to different modes of management. In recent years there has been a push for privatisation on the water sector in general, the reasons for which are manifold, ranging from access to external know-how and capital to synergistic effects through integration of wastewater treatment into other tasks of similar or equal nature. Discussed are various models of public/private partnership (PPP) in wastewater treatment, encompassing for example the delegation of partial tasks or even the proportional or entire transfer of ownership of treatment facilities to private third parties. Decisive for high performance and efficiency is not the legal or organisational form, but rather the clear and unmistakable definition of tasks which are to be assigned to the different parties, customers and all other partners involved, as well as of clear-cut interfaces. On account of the (of course legitimate) profit-oriented perspective of the private sector, some decision-making processes in relation to project implementation (design and construction) and to operational aspects will differ from those typically found on the public sector. This does apply to decisions on investments, financing and on technical solutions too. On the other hand, core competencies in wastewater treatment should not be outsourced, but remain the public bodies' responsibility, even with 'far-reaching' privatisation models. Such core competencies are all efforts geared to sustainable wastewater treatment as life-supporting provision for the future or as contribution to the protection of health and the environment and to the development of infrastructure. Major areas of wastewater treatment and other related tasks are reviewed. The paper concludes with a list of questions on the issue of outsourcing.

  15. Construction of Industrial Electron Beam Plant for Wastewater Treatment

    SciTech Connect

    Han, B.; Kim, J.; Kim, Y.; Kim, S.; Lee, M.; Choi, J.; Ahn, S.; Makarov, I.E.; Ponomarev, A.V.

    2004-10-06

    A pilot plant for treating 1,000 m3/day of dyeing wastewater with e-beam has been constructed and operated since 1998 in Daegu, Korea together with the biological treatment facility. The wastewater from various stages of the existing purification process has been treated with electron beam in this plant, and it gave rise to elaborate the optimal technology of the electron beam treatment of wastewater with increased reliability at instant changes in the composition of wastewater. Installation of the e-beam pilot plant resulted in decolorizing and destructive oxidation of organic impurities in wastewater, appreciable to reduction of chemical reagent consumption, in reduction of the treatment time, and in increase in flow rate limit of existing facilities by 30-40%. Industrial plant for treating 10,000 m3/day, based upon the pilot experimental result, is under construction and will be finished by 2005. This project is supported by the International Atomic Energy Agency (IAEA) and Korean Government.

  16. Steroid plant hormones: effects outside plant kingdom.

    PubMed

    Zhabinskii, Vladimir N; Khripach, Natalia B; Khripach, Vladimir A

    2015-05-01

    Brassinosteroids (BS) are the first group of steroid-hormonal compounds isolated from and acting in plants. Among numerous physiological effects of BS growth stimulation and adaptogenic activities are especially remarkable. In this review, we provide evidence that BS possess similar types of activity also beyond plant kingdom at concentrations comparable with those for plants. This finding allows looking at steroids from a new point of view: how common are the mechanisms of steroid bioregulation in different types of organisms from protozoa to higher animals.

  17. 48. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING N.E. AT ...

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

    48. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING N.E. AT THE AMMONIUM NITRATE BUILDING UNDER CONSTRUCTION, AUGUST 24, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  18. 46. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING N.E. AT ...

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

    46. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING N.E. AT THE LIME-NITROGEN MILL ROOM UNDER CONSTRUCTION, APRIL 23, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  19. 44. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING S.E. AT ...

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

    44. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING S.E. AT THE LIME-NITROGEN OVEN ROOM UNDER CONSTRUCTION, APRIL 23, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  20. 45. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING N.E. AT ...

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

    45. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING N.E. AT THE LIME-NITROGEN OVEN ROOM UNDER CONSTRUCTION, APRIL 23, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  1. 47. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING NORTH AT ...

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

    47. U.S. NITRATE PLANT UNDER CONSTRUCTION, VIEW LOOKING NORTH AT THE AUTOCLAVE BUILDING UNDER CONSTRUCTION, APRIL 23, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  2. [Water treatment efficiency of constructed wetland plant-bed/ditch systems].

    PubMed

    Wang, Zhong-Qiong; Zhang, Rong-Bin; Chen, Qing-Hua; Wei, Hong-Bin; Wang, Wei-Dong

    2012-11-01

    Shijiuyang constructed wetland (SJY-CW) in Jiaxing City adopted plant-bed/ditch systems originated from the natural landscape as its major functioning unit. The constructed root channel technology (CRCT) is the core technique applied within the plant-bed/ditch systems. Monitoring results demonstrated that the wetland had the capability of improving water quality indexes by one rank grade according to the national environmental quality standards for surface water (GB 3838-2002). In order to optimize the water quality improvement function of plant-bed/ditch systems and CRCT, a pilot project in SJY-CW was constructed from May to October, 2010. The project contained 16 independent experimental cells. Orthogonal test design was applied to probe into the effects of constructed root channel layers, plant species combination, and reinforced physical substrates on promoting the water quality amelioration efficiency of the plant-bed/ditch systems. Comprehensively considering water treatment effects, construction difficulty, and construction and maintenance cost, the recommended optimal ways are as follows. Plant straws were preferably paved under subsurface zones by two layers with a gap of 20-30 cm. The preferable plant combination was reed (Phragmites australis) plus wild rice (Zizania caduciflora). Calcite might be applied as alternative reinforced media in some suitable sites of plant-bed/ditch systems. Water treatment effects were compared between pilot project and the whole wetland area of SJY-CW. The results showed that the reinforced pilot project exhibited higher treatment efficiency for nutrients than SJY-CW itself. The removal rates of total nitrogen, total phosphorus, and ammonia nitrogen were increased by about 20% - 40% in the pilot project. This suggested that SJY-CW could release its vast water treatment potential by means of increasing water flux through the subsurface root channel zones of plant beds. Therefore, some adjustment and control measures could be

  3. Temperature, plants, and oxygen: how does season affect constructed wetland performance?

    PubMed

    Stein, Otto R; Hook, Paul B

    2005-01-01

    The influence of temperature and plant-mediated oxygen transfer continues to draw attention from researchers, practitioners and regulators interested in the use of constructed wetlands for wastewater treatment. Because the vast majority of research on constructed wetland performance has been conducted during periods of active plant growth, the true influence of temperature, season, and plant species selection on constructed wetlands performance has not yet been evaluated adequately. In this article, we briefly summarize changes in the understanding of these influences on wetland performance, and suggest that effects of temperature and oxygen transfer are not readily separable because both factors respond to seasonal cycles and because effects of one can offset the other. We further speculate that the net effect of seasonal variation in these factors is such that plant-mediated oxygen transfer affects water treatment most in winter. Results of controlled-environment experiments conducted at Montana State University support these perspectives. Different plant species' capacities to oxidize the root zone responded differently to seasonal cycles of growth and dormancy, and species' effects on wastewater treatment were most pronounced in winter.

  4. Temperature, plants, and oxygen: how does season affect constructed wetland performance?

    PubMed

    Stein, Otto R; Hook, Paul B

    2005-01-01

    The influence of temperature and plant-mediated oxygen transfer continues to draw attention from researchers, practitioners and regulators interested in the use of constructed wetlands for wastewater treatment. Because the vast majority of research on constructed wetland performance has been conducted during periods of active plant growth, the true influence of temperature, season, and plant species selection on constructed wetlands performance has not yet been evaluated adequately. In this article, we briefly summarize changes in the understanding of these influences on wetland performance, and suggest that effects of temperature and oxygen transfer are not readily separable because both factors respond to seasonal cycles and because effects of one can offset the other. We further speculate that the net effect of seasonal variation in these factors is such that plant-mediated oxygen transfer affects water treatment most in winter. Results of controlled-environment experiments conducted at Montana State University support these perspectives. Different plant species' capacities to oxidize the root zone responded differently to seasonal cycles of growth and dormancy, and species' effects on wastewater treatment were most pronounced in winter. PMID:15921285

  5. Relationships between Spatial Metrics and Plant Diversity in Constructed Freshwater Wetlands.

    PubMed

    Brandt, Erika C; Petersen, John E; Grossman, Jake J; Allen, George A; Benzing, David H

    2015-01-01

    The diversity of plant species and their distribution in space are both thought to have important effects on the function of wetland ecosystems. However, knowledge of the relationships between plant species and spatial diversity remains incomplete. In this study, we investigated relationships between spatial pattern and plant species diversity over a five year period following the initial restoration of experimental wetland ecosystems. In 2003, six identical and hydrologically-isolated 0.18 ha wetland "cells" were constructed in former farmland in northeast Ohio. The systems were subjected to planting treatments that resulted in different levels of vascular plant species diversity among cells. Plant species diversity was assessed through annual inventories. Plant spatial pattern was assessed by digitizing low-altitude aerial photographs taken at the same time as the inventories. Diversity metrics derived from the inventories were significantly related to certain spatial metrics derived from the photographs, including cover type diversity and contagion. We found that wetlands with high cover type diversity harbor higher plant species diversity than wetlands with fewer types of patches. We also found significant relationships between plant species diversity and spatial patterning of patch types, but the direction of the effect differed depending on the diversity metric used. Links between diversity and spatial pattern observed in this study suggest that high-resolution aerial imagery may provide wetland scientists with a useful tool for assessing plant diversity. PMID:26296205

  6. Relationships between Spatial Metrics and Plant Diversity in Constructed Freshwater Wetlands

    PubMed Central

    Grossman, Jake J.; Allen, George A.; Benzing, David H.

    2015-01-01

    The diversity of plant species and their distribution in space are both thought to have important effects on the function of wetland ecosystems. However, knowledge of the relationships between plant species and spatial diversity remains incomplete. In this study, we investigated relationships between spatial pattern and plant species diversity over a five year period following the initial restoration of experimental wetland ecosystems. In 2003, six identical and hydrologically-isolated 0.18 ha wetland “cells” were constructed in former farmland in northeast Ohio. The systems were subjected to planting treatments that resulted in different levels of vascular plant species diversity among cells. Plant species diversity was assessed through annual inventories. Plant spatial pattern was assessed by digitizing low-altitude aerial photographs taken at the same time as the inventories. Diversity metrics derived from the inventories were significantly related to certain spatial metrics derived from the photographs, including cover type diversity and contagion. We found that wetlands with high cover type diversity harbor higher plant species diversity than wetlands with fewer types of patches. We also found significant relationships between plant species diversity and spatial patterning of patch types, but the direction of the effect differed depending on the diversity metric used. Links between diversity and spatial pattern observed in this study suggest that high-resolution aerial imagery may provide wetland scientists with a useful tool for assessing plant diversity. PMID:26296205

  7. Application of RFID to High-Reliability Nuclear Power Plant Construction

    SciTech Connect

    Kenji Akagi; Masayuki Ishiwata; Kenji Araki; Jun-ichi Kawahata

    2006-07-01

    In nuclear power plant construction, countless variety of parts, products, and jigs more than one million are treated under construction. Furthermore, strict traceability to the history of material, manufacturing, and installation is required for all products from the start to finish of the construction, which enforce much workforce and many costs at every project. In an addition, the operational efficiency improvement is absolutely essential for the effective construction to reduce the initial investment for construction. As one solution, RFID (Radio Frequent Identification) application technology, one of the fundamental technologies to realize a ubiquitous society, currently expands its functionality and general versatility at an accelerating pace in mass-production industry. Hitachi believes RFID technology can be useful of one of the key solutions for the issues in non-mass production industry as well. Under this situation, Hitachi initiated the development of next generation plant concept (ubiquitous plant construction technology) which utilizes information and RFID technologies. In this paper, our application plans of RFID technology to nuclear power is described. (authors)

  8. Effects of Plant Closing on Employee Attitudes: The Case of the GE Plant in Columbia, Tennessee.

    ERIC Educational Resources Information Center

    Tang, Thomas Li-Ping; Crofford, Amy Beth

    A study examined the effects of plant closing on hourly production employees' attitudes and behavior intentions at a General Electric (GE) plant in Columbia, Tennessee. A survey was constructed and used to collect data from 5 percent of the 400 hourly employees in November 1993, shortly after the announcement of the plant closing. The survey…

  9. Examination of oxygen release from plants in constructed wetlands in different stages of wetland plant life cycle.

    PubMed

    Zhang, Jian; Wu, Haiming; Hu, Zhen; Liang, Shuang; Fan, Jinlin

    2014-01-01

    The quantification of oxygen release by plants in different stages of wetland plant life cycle was made in this study. Results obtained from 1 year measurement in subsurface wetland microcosms demonstrated that oxygen release from Phragmites australis varied from 108.89 to 404.44 mg O₂/m(2)/d during the different periods from budding to dormancy. Plant species, substrate types, and culture solutions had a significant effect on the capacity of oxygen release of wetland plants. Oxygen supply by wetland plants was estimated to potentially support a removal of 300.37 mg COD/m(2)/d or 55.87 mg NH₄-N/m(2)/d. According to oxygen balance analysis, oxygen release by plants could provide 0.43-1.12% of biochemical oxygen demand in typical subsurface-flow constructed wetlands (CWs). This demonstrates that oxygen release of plants may be a potential source for pollutants removal especially in low-loaded CWs. The results make it possible to quantify the role of plants in wastewater purification.

  10. Design and construction of an inexpensive homemade plant growth chamber.

    PubMed

    Katagiri, Fumiaki; Canelon-Suarez, Dario; Griffin, Kelsey; Petersen, John; Meyer, Rachel K; Siegle, Megan; Mase, Keisuke

    2015-01-01

    Plant growth chambers produce controlled environments, which are crucial in making reproducible observations in experimental plant biology research. Commercial plant growth chambers can provide precise controls of environmental parameters, such as temperature, humidity, and light cycle, and the capability via complex programming to regulate these environmental parameters. But they are expensive. The high cost of maintaining a controlled growth environment is often a limiting factor when determining experiment size and feasibility. To overcome the limitation of commercial growth chambers, we designed and constructed an inexpensive plant growth chamber with consumer products for a material cost of $2,300. For a comparable growth space, a commercial plant growth chamber could cost $40,000 or more. Our plant growth chamber had outside dimensions of 1.5 m (W) x 1.8 m (D) x 2 m (H), providing a total growth area of 4.5 m2 with 40-cm high clearance. The dimensions of the growth area and height can be flexibly changed. Fluorescent lights with large reflectors provided a relatively spatially uniform photosynthetically active radiation intensity of 140-250 μmoles/m2/sec. A portable air conditioner provided an ample cooling capacity, and a cooling water mister acted as a powerful humidifier. Temperature, relative humidity, and light cycle inside the chamber were controlled via a z-wave home automation system, which allowed the environmental parameters to be monitored and programmed through the internet. In our setting, the temperature was tightly controlled: 22.2°C±0.8°C. The one-hour average relative humidity was maintained at 75%±7% with short spikes up to ±15%. Using the interaction between Arabidopsis and one of its bacterial pathogens as a test experimental system, we demonstrate that experimental results produced in our chamber were highly comparable to those obtained in a commercial growth chamber. In summary, our design of an inexpensive plant growth chamber

  11. Design and Construction of an Inexpensive Homemade Plant Growth Chamber

    PubMed Central

    Katagiri, Fumiaki; Canelon-Suarez, Dario; Griffin, Kelsey; Petersen, John; Meyer, Rachel K.; Siegle, Megan; Mase, Keisuke

    2015-01-01

    Plant growth chambers produce controlled environments, which are crucial in making reproducible observations in experimental plant biology research. Commercial plant growth chambers can provide precise controls of environmental parameters, such as temperature, humidity, and light cycle, and the capability via complex programming to regulate these environmental parameters. But they are expensive. The high cost of maintaining a controlled growth environment is often a limiting factor when determining experiment size and feasibility. To overcome the limitation of commercial growth chambers, we designed and constructed an inexpensive plant growth chamber with consumer products for a material cost of $2,300. For a comparable growth space, a commercial plant growth chamber could cost $40,000 or more. Our plant growth chamber had outside dimensions of 1.5 m (W) x 1.8 m (D) x 2 m (H), providing a total growth area of 4.5 m2 with 40-cm high clearance. The dimensions of the growth area and height can be flexibly changed. Fluorescent lights with large reflectors provided a relatively spatially uniform photosynthetically active radiation intensity of 140–250 μmoles/m2/sec. A portable air conditioner provided an ample cooling capacity, and a cooling water mister acted as a powerful humidifier. Temperature, relative humidity, and light cycle inside the chamber were controlled via a z-wave home automation system, which allowed the environmental parameters to be monitored and programmed through the internet. In our setting, the temperature was tightly controlled: 22.2°C±0.8°C. The one-hour average relative humidity was maintained at 75%±7% with short spikes up to ±15%. Using the interaction between Arabidopsis and one of its bacterial pathogens as a test experimental system, we demonstrate that experimental results produced in our chamber were highly comparable to those obtained in a commercial growth chamber. In summary, our design of an inexpensive plant growth chamber

  12. Design and construction of an inexpensive homemade plant growth chamber.

    PubMed

    Katagiri, Fumiaki; Canelon-Suarez, Dario; Griffin, Kelsey; Petersen, John; Meyer, Rachel K; Siegle, Megan; Mase, Keisuke

    2015-01-01

    Plant growth chambers produce controlled environments, which are crucial in making reproducible observations in experimental plant biology research. Commercial plant growth chambers can provide precise controls of environmental parameters, such as temperature, humidity, and light cycle, and the capability via complex programming to regulate these environmental parameters. But they are expensive. The high cost of maintaining a controlled growth environment is often a limiting factor when determining experiment size and feasibility. To overcome the limitation of commercial growth chambers, we designed and constructed an inexpensive plant growth chamber with consumer products for a material cost of $2,300. For a comparable growth space, a commercial plant growth chamber could cost $40,000 or more. Our plant growth chamber had outside dimensions of 1.5 m (W) x 1.8 m (D) x 2 m (H), providing a total growth area of 4.5 m2 with 40-cm high clearance. The dimensions of the growth area and height can be flexibly changed. Fluorescent lights with large reflectors provided a relatively spatially uniform photosynthetically active radiation intensity of 140-250 μmoles/m2/sec. A portable air conditioner provided an ample cooling capacity, and a cooling water mister acted as a powerful humidifier. Temperature, relative humidity, and light cycle inside the chamber were controlled via a z-wave home automation system, which allowed the environmental parameters to be monitored and programmed through the internet. In our setting, the temperature was tightly controlled: 22.2°C±0.8°C. The one-hour average relative humidity was maintained at 75%±7% with short spikes up to ±15%. Using the interaction between Arabidopsis and one of its bacterial pathogens as a test experimental system, we demonstrate that experimental results produced in our chamber were highly comparable to those obtained in a commercial growth chamber. In summary, our design of an inexpensive plant growth chamber

  13. The analysis of cracks in high-pressure piping and their effects on strength and lifetime of construction components at the Ignalina nuclear plant

    SciTech Connect

    Aleev, A.; Petkevicius, K.; Senkus, V.

    1997-04-01

    A number of cracks and damages of other sorts have been identified in the high-pressure parts at the Ignalina Nuclear Plant. They are caused by inadequate production- and repair technologies, as well as by thermal, chemical and mechanical processes of their performance. Several techniques are available as predictions of cracks and other defects of pressurized vessels. The choice of an experimental technique should be based on the level of its agreement with the actual processes.

  14. Audit of construction of protective force training facilities at the Pantex Plant

    SciTech Connect

    1995-05-05

    A goal of the Department of Energy project management system is to ensure that projects are necessary to fulfill mission needs and are cost effective. This requires that the Department justify each project and explore competitive alternatives. The objective of this audit was to assess the need to construct protective force training facilities at the Department`s Pantex Plant. Our audit disclosed that (1) construction of a physical training facility was not necessary to fulfill mission needs, and (2) the Department did not consider all viable alternatives to constructing a weapons tactics and training facility. These conditions occurred, in part, because a Justification for New Start was never prepared and approved for the Security Enhancements Major System Acquisition, which included these two projects. We recommended that the Manager, Albuquerque Operations Office, cancel construction of the physical training facility, make needed repairs and upgrades to the existing facilities, and reduce the cost of the Security Enhancements Major System Acquisition accordingly. Implementation of this recommendation will save about $1.7 million. We also recommended that the Manager direct Mason & Hanger to perform economic analyses of all viable alternatives to constructing a weapons tactics and training facility before proceeding with construction. Such analyses could lead to cancellation or rescoping of the proposed facility and result in savings to the Department. Albuquerque management did not agree to cancel construction of the physical training facility, but did agree to perform economic analyses of all viable alternatives to the proposed weapons tactics and training facility before proceeding with construction.

  15. Criteria for determining alternative plants to improve the resource recovery efficiency in constructed wetlands.

    PubMed

    Chiarawatchai, N; Heers, M; Otterpohl, R

    2008-01-01

    The aim of this study is to find the macrophytes that possess high resource recovery efficiency in subsurface-flow constructed wetlands (SFCWs) while not pose any negative effects to the treatment performance. Five criteria were included in this analysis. The suitable alternative plants were proposed according to their availabilities in each climate zone. For their potentials as an energy sources, they are related to plants' productivity as well as growth rate. Concerning the utilization options, plants that possess high economical value and/or versatilities were encouraged. Among the options are handicrafts, fertilizers, animal feeds, construction materials, paper making, and pharmaceutical products. In term of nutrient uptakes, in most cases they were relatively minor comparing to other removal mechanisms in SFCWs. No significant differences in term of treatment efficiency could be found. The proposed species have to be able to tolerate the municipal wastewater. The cost differences of plant propagules between each species are marginal, hence they should not be considered as the main selection criteria. Based on an investigation of 45 species worldwide, the recommendation table is developed with 13 suitable species that fit all the criteria. It appears that there are more than one "most appropriate plant species" in each climatic region. To perform the selection, the operators should weight their preferences on each criteria and the availability of plants in the area.

  16. 21 CFR 111.20 - What design and construction requirements apply to your physical plant?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false What design and construction requirements apply to... § 111.20 What design and construction requirements apply to your physical plant? Any physical plant you... in size, construction, and design to facilitate maintenance, cleaning, and sanitizing operations;...

  17. 21 CFR 111.20 - What design and construction requirements apply to your physical plant?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false What design and construction requirements apply to... § 111.20 What design and construction requirements apply to your physical plant? Any physical plant you... in size, construction, and design to facilitate maintenance, cleaning, and sanitizing operations;...

  18. 75 FR 32313 - Specifications and Drawings for Construction Direct Buried Plant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ... Rural Utilities Service 7 CFR Part 1755 Specifications and Drawings for Construction Direct Buried Plant... Construction of Direct Buried Plant (Form 515a). The revised specification will include new construction units for Fiber-to-the-Home, remove redundant or outdated requirements, and simplify the...

  19. The use of fly ash the thermal power plants in the construction

    NASA Astrophysics Data System (ADS)

    Fediuk, R. S.; Yushin, A. M.

    2015-10-01

    The problems of ecological and radiation safety of the construction of man-made waste like fly ash thermal power plants were researched. The chemical composition of TPPs ashes of Primorsky Territory was studied, defined their specific effective activity of natural radionuclides. The most modern research methods were used - differential thermal analysis, thermogravimetry, X-ray analysis. It was revealed that the ash of the Primorskaya TPP and Partizanskaya TPP has exceed the permissible parameters of radioactivity, so not suitable for use in construction. Ashes of Vladivostok TPP-2 and Artem TPP of Primorsky Region on parameters radioactivity and chemical composition have suitable for use as a filler in the concrete.

  20. Electron beam treatment of textile dyeing wastewater: operation of pilot plant and industrial plant construction.

    PubMed

    Han, B; Kim, J; Kim, Y; Choi, J S; Makarov, I E; Ponomarev, A V

    2005-01-01

    A pilot plant for treating 1000 m3/day of dyeing wastewater with e-beam has been constructed and operated since 1998 in Daegu, Korea together with the biological treatment facility. The wastewater from various stages of the existing purification process has been treated with an electron beam in this plant, and it gave rise to elaborating the optimal technology of the electron beam treatment of wastewater with increased reliability for instant changes in the composition of wastewater. Installation of the e-beam pilot plant resulted in decolorizing and destructive oxidation of organic impurities in wastewater, appreciable reduction of chemical reagent consumption, in reduction of the treatment time, and in increase in the flow rate limit of existing facilities by 30-40%. Industrial plant for treating 10,000 m3/day each, based upon the pilot experimental result, is under construction and will be finished by 2005. This project is supported by the International Atomic Energy Agency (IAEA) and Korean Government.

  1. Plant and Invertebrate Community Changes Caused by Flood-Pulsing in a Constructed Riparian Wetland

    NASA Astrophysics Data System (ADS)

    Caiazza, M. K.; Nieset, J. E.; Romito, A.; de Szalay, F. A.

    2005-05-01

    In 2002, Kent State University constructed a research facility that includes ten independently flooded wetland basins (10 m X 20 m) along a second order creek. We tested the effects of flood-pulsing on the wetland biota by allowing 5 basins (flood-pulse wetlands) to fluctuate with creek water levels to simulate floodplain marshes, and maintaining 5 basins (static wetlands) at constant water levels. We sampled emergent plants and aquatic invertebrates in 2003 and 2004. Abiotic conditions were different between treatments. We collected 83 plant species, and flood pulsing had strong effects on plant communities. Mean species richness and plant cover were higher in static wetlands, and Sorensen's similarity indices between habitat types decreased over time. Plant biomass increased in all wetlands from 2003 to 2004, but mean biomass was not different between treatments. Many dominant plant species were affected by the flood pulsing treatment. Wetland invertebrate communities were diverse (47 taxa), but we detected few responses. Total abundance, species richness, and numbers of most dominant species were not different between treatments. These results indicate that flood-pulsing acted as a stressor on emergent plant communities, but did not strongly impact aquatic macroinvertebrates.

  2. Design and construction of multigenic constructs for plant biotechnology using the GoldenBraid cloning strategy.

    PubMed

    Sarrion-Perdigones, Alejandro; Palaci, Jorge; Granell, Antonio; Orzaez, Diego

    2014-01-01

    GoldenBraid (GB) is an iterative and standardized DNA assembling system specially designed for Multigene Engineering in Plant Synthetic Biology. GB is based on restriction-ligation reactions using type IIS restriction enzymes. GB comprises a collection of standard DNA pieces named "GB parts" and a set of destination plasmids (pDGBs) that incorporate the multipartite assembly of standardized DNA parts. GB reactions are extremely efficient: two transcriptional units (TUs) can be assembled from several basic GBparts in one T-DNA less than 24 h. Moreover, larger assemblies comprising 4-5 TUs are routinely built in less than 2 working weeks. Here we provide a detailed view of the GB methodology. As a practical example, a Bimolecular Fluorescence Complementation construct comprising four TUs in a 12 kb DNA fragment is presented. PMID:24395362

  3. 42. U.S. NITRATE PLANT UNDER CONSTRUCTION, STEEL BEING ERECTED FOR ...

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

    42. U.S. NITRATE PLANT UNDER CONSTRUCTION, STEEL BEING ERECTED FOR THE CARBIDE MILL ROOM, APRIL 23, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  4. 43. U.S. NITRATE PLANT UNDER CONSTRUCTION, STEEL BEING ERECTED FOR ...

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

    43. U.S. NITRATE PLANT UNDER CONSTRUCTION, STEEL BEING ERECTED FOR THE MACHINE SHOP, FEBRUARY 28, 1918. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  5. Biodiversity effects on plant stoichiometry.

    PubMed

    Abbas, Maike; Ebeling, Anne; Oelmann, Yvonne; Ptacnik, Robert; Roscher, Christiane; Weigelt, Alexandra; Weisser, Wolfgang W; Wilcke, Wolfgang; Hillebrand, Helmut

    2013-01-01

    In the course of the biodiversity-ecosystem functioning debate, the issue of multifunctionality of species communities has recently become a major focus. Elemental stoichiometry is related to a variety of processes reflecting multiple plant responses to the biotic and abiotic environment. It can thus be expected that the diversity of a plant assemblage alters community level plant tissue chemistry. We explored elemental stoichiometry in aboveground plant tissue (ratios of carbon, nitrogen, phosphorus, and potassium) and its relationship to plant diversity in a 5-year study in a large grassland biodiversity experiment (Jena Experiment). Species richness and functional group richness affected community stoichiometry, especially by increasing C:P and N:P ratios. The primacy of either species or functional group richness effects depended on the sequence of testing these terms, indicating that both aspects of richness were congruent and complementary to expected strong effects of legume presence and grass presence on plant chemical composition. Legumes and grasses had antagonistic effects on C:N (-27.7% in the presence of legumes, +32.7% in the presence of grasses). In addition to diversity effects on mean ratios, higher species richness consistently decreased the variance of chemical composition for all elemental ratios. The diversity effects on plant stoichiometry has several non-exclusive explanations: The reduction in variance can reflect a statistical averaging effect of species with different chemical composition or a optimization of nutrient uptake at high diversity, leading to converging ratios at high diversity. The shifts in mean ratios potentially reflect higher allocation to stem tissue as plants grew taller at higher richness. By showing a first link between plant diversity and stoichiometry in a multiyear experiment, our results indicate that losing plant species from grassland ecosystems will lead to less reliable chemical composition of forage for

  6. Nitrogen transformations and retention in planted and artificially aerated constructed wetlands.

    PubMed

    Maltais-Landry, Gabriel; Maranger, Roxane; Brisson, Jacques; Chazarenc, Florent

    2009-02-01

    Nitrogen (N) processing in constructed wetlands (CWs) is often variable, and the contribution to N loss and retention by various pathways (nitrification/denitrification, plant uptake and sediment storage) remains unclear. We studied the seasonal variation of the effects of artificial aeration and three different macrophyte species (Phragmites australis, Typha angustifolia and Phalaris arundinacea) on N processing (removal rates, transformations and export) using experimental CW mesocosms. Removal of total nitrogen (TN) was higher in summer and in planted and aerated units, with the highest mean removal in units planted with T. angustifolia. Export of ammonium (NH(4)(+)), a proxy for nitrification limitation, was higher in winter, and in unplanted and non-aerated units. Planted and aerated units had the highest export of oxidized nitrogen (NO(y)), a proxy for reduced denitrification. Redox potential, evapotranspiration (ETP) rates and hydraulic retention times (HRT) were all predictors of TN, NH(4)(+) and NO(y) export, and significantly affected by plants. Denitrification was the main N sink in most treatments accounting for 47-62% of TN removal, while sediment storage was dominant in unplanted non-aerated units and units planted with P. arundinacea. Plant uptake accounted for less than 20% of the removal. Uncertainties about the long-term fate of the N stored in sediments suggest that the fraction attributed to denitrification losses could be underestimated in this study.

  7. CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP640) OVERALL VIEW ...

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

    CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP-640) OVERALL VIEW LOOKING SOUTHEAST; CONSTRUCTION 34 PERCENT COMPLETE. INL PHOTO NUMBER NRTS-60-3034. Holmes, Photographer, 6/23/1960 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  8. CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP640) LOOKING NORTHEAST ...

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

    CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP-640) LOOKING NORTHEAST SHOWING OVERALL BLOCK EXTERIOR WALLS; CONSTRUCTION 65 PERCENT COMPLETE. INL PHOTO NUMBER NRTS-60-4976. Holmes, Photographer, 9/26/1960 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  9. CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP640) LOOKING EAST ...

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

    CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP-640) LOOKING EAST SHOWING EXCAVATION AND FORMING; CONSTRUCTION 6 PERCENT COMPLETE. INL PHOTO NUMBER NRTS-59-4935. J. Anderson, Photographer, 9/21/1959 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  10. CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP640) LOOKING NORTHEAST ...

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

    CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP-640) LOOKING NORTHEAST SHOWING DECK FORMING FOR SOUTH SECTION OF OPERATING CORRIDOR; CONSTRUCTION 44 PERCENT COMPLETE. INL PHOTO NUMBER NRTS-60-3624. Holmes, Photographer, 7/25/1960 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  11. CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP640) LOOKING NORTHWEST, ...

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

    CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CPP-640) LOOKING NORTHWEST, SHOWING FORMING FOR NORTH WALLS OF CELLS 1, 4 AND 5; CONSTRUCTION 21 PERCENT COMPLETE. INL PHOTO NUMBER NRTS-60-1874. Holmes, Photographer, 4/21/1960 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  12. 75 FR 59933 - Specifications and Drawings for Construction of Direct Buried Plant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-29

    ... Plant (Form 515a). The revised specifications will include new construction units for Fiber-to-the-Home... Service 7 CFR Part 1755 Specifications and Drawings for Construction of Direct Buried Plant AGENCY: Rural... titled ``Department Programs and Activities Excluded from Executive Order 12372'' (50 FR 47034),...

  13. New Construct Approaches for Efficient Gene Silencing in Plants

    PubMed Central

    Yan, Hua; Chretien, Robert; Ye, Jingsong; Rommens, Caius M.

    2006-01-01

    An important component of conventional sense, antisense, and double-strand RNA-based gene silencing constructs is the transcriptional terminator. Here, we show that this regulatory element becomes obsolete when gene fragments are positioned between two oppositely oriented and functionally active promoters. The resulting convergent transcription triggers gene silencing that is at least as effective as unidirectional promoter-to-terminator transcription. In addition to short, variably sized, and nonpolyadenylated RNAs, terminator-free cassette produced rare, longer transcripts that reach into the flanking promoter. These read-through products did not influence the efficacy and expression levels of the neighboring hygromycin phosphotransferase gene. Replacement of gene fragments by promoter-derived sequences further increased the extent of gene silencing. This finding indicates that genomic DNA may be a more efficient target for gene silencing than gene transcripts. PMID:16766670

  14. Projecting labor demand and worker immigration at nuclear power plant construction sites: an evaluation of methodology

    SciTech Connect

    Herzog, H.W. Jr; Schlottmann, A.M.; Schriver, W.R.

    1981-12-01

    The study evaluates methodology employed for the projection of labor demand at, and worker migration to, nuclear power plant construction sites. In addition, suggestions are offered as to how this projection methodology might be improved. The study focuses on projection methodologies which forecast either construction worker migration or labor requirements of alternative types of construction activity. Suggested methodological improvements relate both to institutional factors within the nuclear power plant construction industry, and to a better use of craft-specific data on construction worker demand/supply. In addition, the timeliness and availability of the regional occupational data required to support, or implement these suggestions are examined.

  15. Evapotranspiration from pilot-scale constructed wetlands planted with Phragmites australis in a Mediterranean environment.

    PubMed

    Milani, Mirco; Toscano, Attilio

    2013-01-01

    This article reports the results of evapotranspiration (ET) experiments carried out in Southern Italy (Sicily) in a pilot-scale constructed wetland (CW) made of a combination of vegetated (Phragmites australis) and unvegetated sub-surface flow beds. Domestic wastewater from a conventional wastewater treatment plant was used to fill the beds. Microclimate data was gathered from an automatic weather station close to the experimental plant. From June to November 2009 and from April to November 2010, ET values were measured as the amount of water needed to restore the initial volume in the beds after a certain period. Cumulative reference evapotranspiration (ET(0)) was similar to the cumulative ET measured in the beds without vegetation (ET(con)), while the Phragmites ET (ET (phr) ) was significantly higher underlining the effect of the vegetation. The plant coefficient of P. australis (K(p)) was very high (up to 8.5 in August 2009) compared to the typical K(c) for agricultural crops suggesting that the wetland environment was subjected to strong "clothesline" and "oasis" effects. According to the FAO 56 approach, K(p) shows different patterns and values in relation to growth stages correlating significantly to stem density, plant height and total leaves. The mean Water Use Efficiency (WUE) value of P. australis was quite low, about 2.27 g L(-1), probably due to the unlimited water availability and the lack of the plant's physiological adaptations to water conservation. The results provide useful and valid information for estimating ET rates in small-scale constructed wetlands since ET is a relevant issue in arid and semiarid regions. In these areas CW feasibility for wastewater treatment and reuse should also be carefully evaluated for macrophytes in relation to their WUE values.

  16. Feral biofuel crop effects in constructed wet prairie and oak savannah communities

    EPA Science Inventory

    We examined the potential effects of feral biofuel crop escapes on constructed plant communities growing in outdoor mesocosms. Mesocosms containing wet prairie or oak savannah communities were exposed to two temperature levels (ambient and elevated) and two moisture levels (cont...

  17. Yannawa wastewater treatment plant (Bangkok, Thailand): design, construction and operation.

    PubMed

    Kirkwood, S

    2004-01-01

    Yannawa Wastewater Treatment plant (Phase 1) serves a population equivalent of 500,000 and is located on a restricted site within the city of Bangkok, Thailand. Secondary treatment is based on the CASS sequencing batch reactor (SBR) process and the plant is one of the largest multi-storey SBRs in the world. The limitation of available site area, the ground conditions and the characteristics of the wastewater to be treated set a series of challenges for the designers, contractors and commissioning and operational staff. This paper briefly describes the collection system, the process selection and the treatment streams of the wastewater treatment plant. The SBR secondary treatment plant is described in more detail. The problems that arose during commissioning and operation and the solutions made possible by the use of an SBR type of process are discussed. Details of plant performance during performance testing and during the first three years of plant operation are provided.

  18. Fundamentals of Physical Plant Management, Planning, and Construction.

    ERIC Educational Resources Information Center

    Smith, J. McCree; And Others

    Principles for guiding the administrative officer in charge of developing a service organization on a campus and a brief description of main components of plant planning are given. The rationale and implementation in areas of personnel, finance, and facilities are discussed and recommendations for maintaining a physical plant planning office are…

  19. A simple Gateway-assisted construction system of TALEN genes for plant genome editing

    PubMed Central

    Kusano, Hiroaki; Onodera, Hitomi; Kihira, Miho; Aoki, Hiromi; Matsuzaki, Hikaru; Shimada, Hiroaki

    2016-01-01

    TALEN is an artificial nuclease being applied for sequence-specific genome editing. For the plant genome editing, a pair of TALEN genes is expressed in the cells, and a binary plasmid for Agrobacterium-mediated transformation should be assembled. We developed a novel procedure using the Gateway-assisted plasmids, named Emerald–Gateway TALEN system. We constructed entry vectors, pPlat plasmids, for construction of a desired TALEN gene using Platinum Gate TALEN kit. We also created destination plasmid, pDual35SGw1301, which allowed two TALEN genes to both DNA strands to recruit using Gateway technology. Resultant TALEN genes were evaluated by the single-strand annealing (SSA) assay in E. coli cells. By this assay, the TALENs recognized the corresponding targets in the divided luciferase gene, and induced a specific recombination to generate an active luciferase gene. Using the TALEN genes constructed, we created a transformant potato cells in which a site-specific mutation occurred at the target site of the GBSS gene. This suggested that our system worked effectively and was applicable as a convenient tool for the plant genome editing. PMID:27452606

  20. A simple Gateway-assisted construction system of TALEN genes for plant genome editing.

    PubMed

    Kusano, Hiroaki; Onodera, Hitomi; Kihira, Miho; Aoki, Hiromi; Matsuzaki, Hikaru; Shimada, Hiroaki

    2016-01-01

    TALEN is an artificial nuclease being applied for sequence-specific genome editing. For the plant genome editing, a pair of TALEN genes is expressed in the cells, and a binary plasmid for Agrobacterium-mediated transformation should be assembled. We developed a novel procedure using the Gateway-assisted plasmids, named Emerald-Gateway TALEN system. We constructed entry vectors, pPlat plasmids, for construction of a desired TALEN gene using Platinum Gate TALEN kit. We also created destination plasmid, pDual35SGw1301, which allowed two TALEN genes to both DNA strands to recruit using Gateway technology. Resultant TALEN genes were evaluated by the single-strand annealing (SSA) assay in E. coli cells. By this assay, the TALENs recognized the corresponding targets in the divided luciferase gene, and induced a specific recombination to generate an active luciferase gene. Using the TALEN genes constructed, we created a transformant potato cells in which a site-specific mutation occurred at the target site of the GBSS gene. This suggested that our system worked effectively and was applicable as a convenient tool for the plant genome editing. PMID:27452606

  1. A Hardy Plant Facilitates Nitrogen Removal via Microbial Communities in Subsurface Flow Constructed Wetlands in Winter.

    PubMed

    Wang, Penghe; Zhang, Hui; Zuo, Jie; Zhao, Dehua; Zou, Xiangxu; Zhu, Zhengjie; Jeelani, Nasreen; Leng, Xin; An, Shuqing

    2016-01-01

    The plants effect in subsurface flow constructed wetlands (SSF-CWs) is controversial, especially at low temperatures. Consequently, several SSF-CWs planted with Iris pseudacorus (CWI) or Typha orientalis Presl. (CWT) and several unplanted ones (CWC) were set up and fed with secondary effluent of sewage treatment plant during the winter in Eastern China. The 16S rDNA Illumina Miseq sequencing analysis indicated the positive effects of I. pseudacorus on the bacterial community richness and diversity in the substrate. Moreover, the community compositions of the bacteria involved with denitrification presented a significant difference in the three systems. Additionally, higher relative abundances of nitrifying bacteria (0.4140%, 0.2402% and 0.4318% for Nitrosomonas, Nitrosospira and Nitrospira, respectively) were recorded in CWI compared with CWT (0.2074%, 0.0648% and 0.0181%, respectively) and CWC (0.3013%, 0.1107% and 0.1185%, respectively). Meanwhile, the average removal rates of NH4(+)-N and TN in CWI showed a prominent advantage compared to CWC, but no distinct advantage was found in CWT. The hardy plant I. pseudacorus, which still had active root oxygen release in cold temperatures, positively affected the abundance of nitrifying bacteria in the substrate, and accordingly was supposed to contribute to a comparatively high nitrogen removal efficiency of the system during the winter. PMID:27646687

  2. A Hardy Plant Facilitates Nitrogen Removal via Microbial Communities in Subsurface Flow Constructed Wetlands in Winter

    PubMed Central

    Wang, Penghe; Zhang, Hui; Zuo, Jie; Zhao, Dehua; Zou, Xiangxu; Zhu, Zhengjie; Jeelani, Nasreen; Leng, Xin; An, Shuqing

    2016-01-01

    The plants effect in subsurface flow constructed wetlands (SSF-CWs) is controversial, especially at low temperatures. Consequently, several SSF-CWs planted with Iris pseudacorus (CWI) or Typha orientalis Presl. (CWT) and several unplanted ones (CWC) were set up and fed with secondary effluent of sewage treatment plant during the winter in Eastern China. The 16S rDNA Illumina Miseq sequencing analysis indicated the positive effects of I. pseudacorus on the bacterial community richness and diversity in the substrate. Moreover, the community compositions of the bacteria involved with denitrification presented a significant difference in the three systems. Additionally, higher relative abundances of nitrifying bacteria (0.4140%, 0.2402% and 0.4318% for Nitrosomonas, Nitrosospira and Nitrospira, respectively) were recorded in CWI compared with CWT (0.2074%, 0.0648% and 0.0181%, respectively) and CWC (0.3013%, 0.1107% and 0.1185%, respectively). Meanwhile, the average removal rates of NH4+-N and TN in CWI showed a prominent advantage compared to CWC, but no distinct advantage was found in CWT. The hardy plant I. pseudacorus, which still had active root oxygen release in cold temperatures, positively affected the abundance of nitrifying bacteria in the substrate, and accordingly was supposed to contribute to a comparatively high nitrogen removal efficiency of the system during the winter. PMID:27646687

  3. A Hardy Plant Facilitates Nitrogen Removal via Microbial Communities in Subsurface Flow Constructed Wetlands in Winter

    NASA Astrophysics Data System (ADS)

    Wang, Penghe; Zhang, Hui; Zuo, Jie; Zhao, Dehua; Zou, Xiangxu; Zhu, Zhengjie; Jeelani, Nasreen; Leng, Xin; An, Shuqing

    2016-09-01

    The plants effect in subsurface flow constructed wetlands (SSF-CWs) is controversial, especially at low temperatures. Consequently, several SSF-CWs planted with Iris pseudacorus (CWI) or Typha orientalis Presl. (CWT) and several unplanted ones (CWC) were set up and fed with secondary effluent of sewage treatment plant during the winter in Eastern China. The 16S rDNA Illumina Miseq sequencing analysis indicated the positive effects of I. pseudacorus on the bacterial community richness and diversity in the substrate. Moreover, the community compositions of the bacteria involved with denitrification presented a significant difference in the three systems. Additionally, higher relative abundances of nitrifying bacteria (0.4140%, 0.2402% and 0.4318% for Nitrosomonas, Nitrosospira and Nitrospira, respectively) were recorded in CWI compared with CWT (0.2074%, 0.0648% and 0.0181%, respectively) and CWC (0.3013%, 0.1107% and 0.1185%, respectively). Meanwhile, the average removal rates of NH4+-N and TN in CWI showed a prominent advantage compared to CWC, but no distinct advantage was found in CWT. The hardy plant I. pseudacorus, which still had active root oxygen release in cold temperatures, positively affected the abundance of nitrifying bacteria in the substrate, and accordingly was supposed to contribute to a comparatively high nitrogen removal efficiency of the system during the winter.

  4. A Hardy Plant Facilitates Nitrogen Removal via Microbial Communities in Subsurface Flow Constructed Wetlands in Winter.

    PubMed

    Wang, Penghe; Zhang, Hui; Zuo, Jie; Zhao, Dehua; Zou, Xiangxu; Zhu, Zhengjie; Jeelani, Nasreen; Leng, Xin; An, Shuqing

    2016-09-20

    The plants effect in subsurface flow constructed wetlands (SSF-CWs) is controversial, especially at low temperatures. Consequently, several SSF-CWs planted with Iris pseudacorus (CWI) or Typha orientalis Presl. (CWT) and several unplanted ones (CWC) were set up and fed with secondary effluent of sewage treatment plant during the winter in Eastern China. The 16S rDNA Illumina Miseq sequencing analysis indicated the positive effects of I. pseudacorus on the bacterial community richness and diversity in the substrate. Moreover, the community compositions of the bacteria involved with denitrification presented a significant difference in the three systems. Additionally, higher relative abundances of nitrifying bacteria (0.4140%, 0.2402% and 0.4318% for Nitrosomonas, Nitrosospira and Nitrospira, respectively) were recorded in CWI compared with CWT (0.2074%, 0.0648% and 0.0181%, respectively) and CWC (0.3013%, 0.1107% and 0.1185%, respectively). Meanwhile, the average removal rates of NH4(+)-N and TN in CWI showed a prominent advantage compared to CWC, but no distinct advantage was found in CWT. The hardy plant I. pseudacorus, which still had active root oxygen release in cold temperatures, positively affected the abundance of nitrifying bacteria in the substrate, and accordingly was supposed to contribute to a comparatively high nitrogen removal efficiency of the system during the winter.

  5. Greenhouse gas production and efficiency of planted and artificially aerated constructed wetlands.

    PubMed

    Maltais-Landry, Gabriel; Maranger, Roxane; Brisson, Jacques; Chazarenc, Florent

    2009-03-01

    Greenhouse gas (GHG) emissions by constructed wetlands (CWs) could mitigate the environmental benefits of nutrient removal in these man-made ecosystems. We studied the effect of 3 different macrophyte species and artificial aeration on the rates of nitrous oxide (N(2)O), carbon dioxide (CO(2)) and methane (CH(4)) production in CW mesocosms over three seasons. CW emitted 2-10 times more GHG than natural wetlands. Overall, CH(4) was the most important GHG emitted in unplanted treatments. Oxygen availability through artificial aeration reduced CH(4) fluxes. Plant presence also decreased CH(4) fluxes but favoured CO(2) production. Nitrous oxide had a minor contribution to global warming potential (GWP<15%). The introduction of oxygen through artificial aeration combined with plant presence, particularly Typha angustifolia, had the overall best performance among the treatments tested in this study, including lowest GWP, greatest nutrient removal, and best hydraulic properties.

  6. Recurrent mistakes in power plant design, construction, and operation

    SciTech Connect

    Kautz, H.R.

    1995-12-31

    The mistakes made during planning and design (calculation), erection, and operation of power plants will be discussed in detail. The erection time, state of the regulatory guides and of the art are decisive for plant design. Errors with respect to materials selection, manufacturing, and welding are critical for the service life. Frequently, errors during examinations for maintenance purposes and for assessing the remaining life are due to mistakes at the beginning of the service life of a component. Last, but not least, plant cycle chemistry errors and operating errors will be discussed by examples.

  7. Antiartherosclerotic Effects of Plant Flavonoids

    PubMed Central

    Gunasekaran, Baskaran; Shukor, Mohd Yunus

    2014-01-01

    Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is generally associated with cardiovascular diseases such as strokes, heart attacks, and peripheral vascular diseases. Since the usage of the synthetic drug, statins, leads to various side effects, the plants flavonoids with antiartherosclerotic activity gained much attention and were proven to reduce the risk of atherosclerosis in vitro and in vivo based on different animal models. The flavonoids compounds also exhibit lipid lowering effects and anti-inflammatory and antiatherogenic properties. The future development of flavonoids-based drugs is believed to provide significant effects on atherosclerosis and its related diseases. This paper discusses the antiatherosclerotic effects of selected plant flavonoids such as quercetin, kaempferol, myricetin, rutin, naringenin, catechin, fisetin, and gossypetin. PMID:24971331

  8. The effect of gravity on plant germination.

    PubMed

    Takakura, T; Goto, E; Tanaka, M

    1996-01-01

    An axis clinostat was constructed to create micro and negative gravity also a rotated flat disk was constructed with different rotation rates to give increased gravity, by centrifugal force up to 48 g. Rice seeds were grown on agar in tubes at the constant air temperature of 20 degrees C under an average light condition of 110 micromol/m2/sec(PPF). Humidity was not controlled but was maintained above 90%. Since the tube containers were not large enough for long cultivation, shoot and root growth were observed every 12 hours until the sixth day from seeding. The lengths of shoots and roots for each individual plant were measured on the last day. The stem lengths were increased by microgravity but the root lengths were not. Under the negative gravity, negative orthogeotropism and under microgravity, diageotropism was observed. No significant effect of increased gravity was observed on shoot and root growth.

  9. The effect of gravity on plant germination.

    PubMed

    Takakura, T; Goto, E; Tanaka, M

    1996-01-01

    An axis clinostat was constructed to create micro and negative gravity also a rotated flat disk was constructed with different rotation rates to give increased gravity, by centrifugal force up to 48 g. Rice seeds were grown on agar in tubes at the constant air temperature of 20 degrees C under an average light condition of 110 micromol/m2/sec(PPF). Humidity was not controlled but was maintained above 90%. Since the tube containers were not large enough for long cultivation, shoot and root growth were observed every 12 hours until the sixth day from seeding. The lengths of shoots and roots for each individual plant were measured on the last day. The stem lengths were increased by microgravity but the root lengths were not. Under the negative gravity, negative orthogeotropism and under microgravity, diageotropism was observed. No significant effect of increased gravity was observed on shoot and root growth. PMID:11538807

  10. Plant response to utility right of way construction in the Mojave Desert

    NASA Astrophysics Data System (ADS)

    Lathrop, Earl W.; Archbold, Edwin F.

    1980-05-01

    Disturbance of flora from utility construction tends to generate new plant growth. This growth changes productivity, diversity, and stability. Although the enhancement of vegetation may balance out the biomass destroyed by the original disturbance, it often adversely affects the quality of the vegetation. Percentage composition of the dominant long-lived perennials combined with quantitative measures are used to assess longterm effects of utility corridor construction. Differential effects of enhancement of vegetation are found along road edges, enhancement under wires of powerlines, and over trenches dug for pipelines. Areas under powerline pylons seem to receive the greatest damage and also show the most variable recovery of vegetation. Significant recovery rates are noticeable where the time span between year of construction has allowed for considerable regrowth of the older corridor. Recovery rates depend on soil type, landform, and other physical features of the disturbed sites. Drastic disturbance in one area or transect site may impede vegetation recovery, whereas slight disturbance might enhance vegetation in another, tending to offset the effect of the drastic disturbance. Disturbed areas and control areas may appear to have similar vegetation covers, biomasses, and densities, but these similarities often vanish when one examines qualitative aspects, such as proportion of long-lived species and presence of characteristic dominants.

  11. Purification ability and carbon dioxide flux from surface flow constructed wetlands treating sewage treatment plant effluent.

    PubMed

    Wu, Haiming; Lin, Li; Zhang, Jian; Guo, Wenshan; Liang, Shuang; Liu, Hai

    2016-11-01

    In this study, a two-year experiment was carried out to investigate variation of carbon dioxide (CO2) flux from free water surface constructed wetlands (FWS CW) systems treating sewage treatment plant effluent, and treatment performance was also evaluated. The better 74.6-76.6% COD, 92.7-94.4% NH4(+)-N, 60.1-84.7% TN and 49.3-70.7% TP removal efficiencies were achieved in planted CW systems compared with unplanted systems. The planted CW was a net CO2 sink, while the unplanted CW was a net CO2 source in the entire study period. An obvious annual and seasonal variability of CO2 fluxes from different wetland systems was also presented with the average CO2 flux ranging from -592.83mgm(-2)h(-1) to 553.91mgm(-2)h(-1) during 2012-2013. In addition, the net exchange of CO2 between CW systems and the atmosphere was significantly affected by air temperature, and the presence of plants also had the significant effect on total CO2 emissions.

  12. Purification ability and carbon dioxide flux from surface flow constructed wetlands treating sewage treatment plant effluent.

    PubMed

    Wu, Haiming; Lin, Li; Zhang, Jian; Guo, Wenshan; Liang, Shuang; Liu, Hai

    2016-11-01

    In this study, a two-year experiment was carried out to investigate variation of carbon dioxide (CO2) flux from free water surface constructed wetlands (FWS CW) systems treating sewage treatment plant effluent, and treatment performance was also evaluated. The better 74.6-76.6% COD, 92.7-94.4% NH4(+)-N, 60.1-84.7% TN and 49.3-70.7% TP removal efficiencies were achieved in planted CW systems compared with unplanted systems. The planted CW was a net CO2 sink, while the unplanted CW was a net CO2 source in the entire study period. An obvious annual and seasonal variability of CO2 fluxes from different wetland systems was also presented with the average CO2 flux ranging from -592.83mgm(-2)h(-1) to 553.91mgm(-2)h(-1) during 2012-2013. In addition, the net exchange of CO2 between CW systems and the atmosphere was significantly affected by air temperature, and the presence of plants also had the significant effect on total CO2 emissions. PMID:27544264

  13. CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CP640) LOOKING NORTHWEST ...

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

    CONSTRUCTION PROGRESS PHOTO OF HOT PILOT PLANT (CP-640) LOOKING NORTHWEST SHOWING FORMING AND PLACEMENT OF REINFORCING STEEL FOR SOUTH WALLS OF CELLS 1, 3, 4 AND 5 AND WEST WALL FOR CELLS 1 AND 2; CONSTRUCTION 13 PERCENT COMPLETE. INL PHOTO NUMBER NRTS 59-6436. J. Anderson, Photographer, 12/18/1959 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  14. Comprehensive evaluation of cost effectiveness of solar electric power plants

    NASA Astrophysics Data System (ADS)

    Ibragimov, D. Y.; Filatov, A. I.

    1984-02-01

    The cost effectiveness of constructing a solar heating and electric power plant is evaluated on the basis of a compatibility analysis of its combination with a thermal electric power plant and a boiler-type heating plant, taking into account comprehensively economic factors as well as power requirements. Two variants of such a combination are considered and compared, assuming equal heating power and equal electric power respectively. Equations are set up for each variant covering fixed and variable costs of generating electric power and generating heat, as basis for comparing the two variants and optimizing them with respect to normalized annual total cost. Nomograms plotted for convenient numerical calculation of maximum economically worthwhile capital investment in a solar heating and electric power plant, depending on changes in various operating parameters, reveal that, as the time for constructing such a plant becomes longer, this maximum worthwhile investment in it increases for variant 1 and decreases for variant 2.

  15. Migration and Residential Location of Workers at Nuclear Power Plant Construction Sites Forecasting Methodology

    SciTech Connect

    Malhotra, S.; Manninen, D.

    1981-04-01

    The primary objective of this study was to improve the accuracy of socioeconomic impact assessments by providing an improved methodology for predicting the number of inmigrating workers and their residential location patterns at future nuclear power plant construction projects. Procedures for estimating several other variables which have important implications with respect to socioeconomic impact assessment (i.e., relocation of dependents, intention to remain in the area, type of housing selected, marital status, and average family size) were also developed. The analysis was based on worker survey data from 28 surveys which were conducted at 13 nuclear power plant construction sites. These survey data were examined to identify patterns of variation in variables of interest across sites as well as across various worker groups. In addition, considerable secondary data reflecting various regional and project characteristics were gathered for each site. These data were used to estimate the effects of factors underlying the observed variation in craft-specific migrant proportions and the residential location patterns of inmigrating workers across sites and surveys. The results of these analyses were then used as a basis for the specification of the forecasting procedures.

  16. Effects of plants and plant products on the testis

    PubMed Central

    D'Cruz, Shereen Cynthia; Vaithinathan, Selvaraju; Jubendradass, Rajamanickam; Mathur, Premendu Prakash

    2010-01-01

    For centuries, plants and plant-based products have been used as a valuable and safe natural source of medicines for treating various ailments. The therapeutic potential of most of these plants could be ascribed to their anticancer, antidiabetic, hepatoprotective, cardioprotective, antispasmodic, analgesic and various other pharmacological properties. However, several commonly used plants have been reported to adversely affect male reproductive functions in wildlife and humans. The effects observed with most of the plant and plant-based products have been attributed to the antispermatogenic and/or antisteroidogenic properties of one or more active ingredients. This review discusses the detrimental effects of some of the commonly used plants on various target cells in the testis. A deeper insight into the molecular mechanisms of action of these natural compounds could pave the way for developing therapeutic strategies against their toxicity. PMID:20562897

  17. Anabolic effect of plant brassinosteroid

    PubMed Central

    Esposito, Debora; Komarnytsky, Slavko; Shapses, Sue; Raskin, Ilya

    2011-01-01

    Brassinosteroids are plant-derived polyhydroxylated derivatives of 5a-cholestane, structurally similar to cholesterol-derived animal steroid hormones and insect ecdysteroids, with no known function in mammals. 28-Homobrassinolide (HB), a steroidal lactone with potent plant growth-promoting property, stimulated protein synthesis and inhibited protein degradation in L6 rat skeletal muscle cells (EC50 4 μM) mediated in part by PI3K/Akt signaling pathway. Oral administration of HB (20 or 60 mg/kg/d for 24 d) to healthy rats fed normal diet (protein content 23.9%) increased food intake, body weight gain, lean body mass, and gastrocnemius muscle mass as compared with vehicle-treated controls. The effect of HB administration increased slightly in animals fed a high-protein diet (protein content 39.4%). Both oral (up to 60 mg/kg) and subcutaneous (up to 4 mg/kg) administration of HB showed low androgenic activity when tested in the Hershberger assay. Moreover, HB showed no direct binding to the androgen receptor in vitro. HB treatment was also associated with an improved physical fitness of untrained healthy rats, as evident from a 6.7% increase in lower extremity strength, measured by grip test. In the gastrocnemius muscle of castrated animals, HB treatment significantly increased the number of type IIa and IIb fibers and the cross-sectional area of type I and type IIa fibers. These findings suggest that oral application of HB triggers selective anabolic response with minimal or no androgenic side-effects and begin to elucidate the putative cellular targets for plant brassinosteroids in mammals.—Esposito, D., Komarnytsky, S., Shapses, S., Raskin, I. Anabolic effect of plant brassinosteroid. PMID:21746867

  18. The new Kaiserstuhl coking plant: The heating system -- Design, construction and initial operating experience

    SciTech Connect

    Strunk, J.

    1996-12-31

    At the end of 1992 the new coke plant Kaiserstuhl in Dortmund/Germany with presently the largest coke ovens world-wide started its production operation in close linkage to the Krupp-Hoesch Metallurgical Works after about 35 months construction time. This plant incorporating comprehensive equipment geared to improve environmental protection is also considered as the most modern coke plant of the world. The heating-system and first results of operation will be presented.

  19. Opportunities to expedite the construction of new coal-based power plants

    SciTech Connect

    Thomas G. Kraemer; Georgia Nelson; Robert Card; E. Linn Draper, Jr.; Michael J. Mudd

    2004-07-01

    US Secretary of Energy Spencer Abraham requested that the National Coal Council prepare a study identifying 'which opportunities could expedite the construction of new coal-fired electricity generation.' He also requested that the Council 'examine opportunities and incentives for additional emissions reduction including evaluating and replacing the oldest portion of our coal-fired power plant fleet with more efficient and lower emitting coal-fired plants.' A study group of experts who conducted the work can be found in Appendix D. The National Coal Council found the following: Coal is the fuel of choice now, and will remain so into the future; Natural gas has been the dominant fuel for new power plants in the last decade; Coal provides a pathway for greater energy independence; There is renewed interest in using coal to fuel new power plants; Generators are expected to remain credit worthy; Permitting delays have been an impediment to building new coal plants; Environmental regulatory approaches have been an impediment to building new coal plants; Uncertainty about CO{sub 2} emission reductions has been an impediment to the construction of new coalbased power plants; Incentives are still needed to facilitate the construction of advanced coal-based power plants; Lack of a regional planning approach has been an impediment to the construction of new coal-based power plants; and Infrastructure hurdles are impediments to the construction of new coal-based power plants. The Council's recommendations include: Streamline the permitting process; Recognize the strategic importance of integrated gasification combined cycle (IGCC) technology; Recognize the importance of other coal-based technologies; Encourage regional planning; Continue with meaningful R&D and with technology demonstration; Provide meaningful incentives for the commercialization and deployment of new advanced coal-based technologies. 7 apps.

  20. Technical WOrk Plan for: Construction Effects Monitoring

    SciTech Connect

    S. Goodin

    2006-09-14

    This document is the technical work plan (TWP) for performing the Construction Effects Monitoring (CEM) activity, which is one of 20 testing and monitoring activities included in Performance Confirmation Plan (BSC 2004 [DIRS 172452]). Collectively, the 20 activities make up the Performance Confirmation Program described in the plan. Each of the other 19 activities will have a separate TWP. This plan, though titled Construction Effects Monitoring, in accordance with the Performance Confirmation Plan, also includes testing that may be performed in addition to monitoring, if required. Performance confirmation is required by regulation 10 CFR Part 63 [DIRS 173273], and was started during site characterization (consistent with the regulation) and will continue until permanent closure of the repository (10 CFR 63.13 1 (b) [DIRS 173273]). This CEM activity has two primary goals: (1) to collect, analyze, and report on repository rock properties data for the purpose of confirming geotechnical and design parameters used in repository design, and (2) to provide information intended to confirm that the ability to retrieve waste from the repository has been preserved. It will be necessary for information from this CEM activity to be evaluated in combination with that obtained from other Performance Confirmation Program activities to achieve these goals. These relationships with other Performance Confirmation Program activities (e.g., drift inspection, subsurface mapping, and seismicity monitoring) will be discussed in later sections of this TWP.

  1. Construction costs, payback times, and the leaf economics of carnivorous plants.

    PubMed

    Karagatzides, Jim D; Ellison, Aaron M

    2009-09-01

    Understanding how different plant species and functional types "invest" carbon and nutrients is a major goal of plant ecologists. Two measures of such investments are "construction costs" (carbon needed to produce each gram of tissue) and associated "payback times" for photosynthesis to recover construction costs. These measurements integrate among traits used to assess leaf-trait scaling relationships. Carnivorous plants are model systems for examining mechanisms of leaf-trait coordination, but no studies have measured simultaneously construction costs of carnivorous traps and their photosynthetic rates to determine payback times of traps. We measured mass-based construction costs (CC(mass)) and photosynthesis (A(mass)) for traps, leaves, roots, and rhizomes of 15 carnivorous plant species grown under greenhouse conditions. There were highly significant differences among species in CC(mass) for each structure. Mean CC(mass) of carnivorous traps (1.14 ± 0.24 g glucose/g dry mass) was significantly lower than CC(mass) of leaves of 267 noncarnivorous plant species (1.47 ± 0.17), but all carnivorous plants examined had very low A(mass) and thus, long payback times (495-1551 h). Our results provide the first clear estimates of the marginal benefits of botanical carnivory and place carnivorous plants at the "slow and tough" end of the universal spectrum of leaf traits.

  2. Native plants for effective coastal wetland restoration

    USGS Publications Warehouse

    Howard, Rebecca J.

    2003-01-01

    Plant communities, along with soils and appropriate water regimes, are essential components of healthy wetland systems. In Louisiana, the loss of wetland habitat continues to be an issue of major concern. Wetland loss is caused by several interacting factors, both natural and human-induced (e.g., erosion and saltwater intrusion from the construction of canals and levees). Recent estimates of annual coastal land loss rates of about 62 km2 (24 mi2 ) over the past decade emphasize the magnitude of this problem. In an attempt to slow the rate of loss and perhaps halt the overall trend, resource managers in Louisiana apply various techniques to restore damaged or degraded habitats to functioning wetland systems.Researchers at the U.S. Geological Survey’s National Wetlands Research Center (NWRC) have cooperated with the Louisiana Department of Natural Resources in studies that address effective restoration strategies for coastal wetlands. The studies have identified differences in growth that naturally exist in native Louisiana wetland plant species and genetic varieties (i.e., clones) within species. Clones of a species have a distinctive genetic identity, and some clones may also have distinctive growth responses under various environmental conditions (i.e., preferences). Indeed, large areas of coastal marsh are typically populated by several clones of a plant species, each growing in a microenvironment suited to its preferences.These studies will provide information that will assist resource managers in selecting plant species and clones of species with known growth characteristics that can be matched to environmental conditions at potential restoration sites. Before the studies began, a collection of several clones from four plant species native to coastal Louisiana was established. The species collected included saltgrass (Distichlis spicata), common reed (Phragmites australis), giant bulrush (Schoenoplectus californicus), and saltmarsh bulrush (Schoenoplectus

  3. Chitosan Effects on Plant Systems.

    PubMed

    Malerba, Massimo; Cerana, Raffaella

    2016-06-23

    Chitosan (CHT) is a natural, safe, and cheap product of chitin deacetylation, widely used by several industries because of its interesting features. The availability of industrial quantities of CHT in the late 1980s enabled it to be tested in agriculture. CHT has been proven to stimulate plant growth, to protect the safety of edible products, and to induce abiotic and biotic stress tolerance in various horticultural commodities. The stimulating effect of different enzyme activities to detoxify reactive oxygen species suggests the involvement of hydrogen peroxide and nitric oxide in CHT signaling. CHT could also interact with chromatin and directly affect gene expression. Recent innovative uses of CHT include synthesis of CHT nanoparticles as a valuable delivery system for fertilizers, herbicides, pesticides, and micronutrients for crop growth promotion by a balanced and sustained nutrition. In addition, CHT nanoparticles can safely deliver genetic material for plant transformation. This review presents an overview on the status of the use of CHT in plant systems. Attention was given to the research that suggested the use of CHT for sustainable crop productivity.

  4. Chitosan Effects on Plant Systems

    PubMed Central

    Malerba, Massimo; Cerana, Raffaella

    2016-01-01

    Chitosan (CHT) is a natural, safe, and cheap product of chitin deacetylation, widely used by several industries because of its interesting features. The availability of industrial quantities of CHT in the late 1980s enabled it to be tested in agriculture. CHT has been proven to stimulate plant growth, to protect the safety of edible products, and to induce abiotic and biotic stress tolerance in various horticultural commodities. The stimulating effect of different enzyme activities to detoxify reactive oxygen species suggests the involvement of hydrogen peroxide and nitric oxide in CHT signaling. CHT could also interact with chromatin and directly affect gene expression. Recent innovative uses of CHT include synthesis of CHT nanoparticles as a valuable delivery system for fertilizers, herbicides, pesticides, and micronutrients for crop growth promotion by a balanced and sustained nutrition. In addition, CHT nanoparticles can safely deliver genetic material for plant transformation. This review presents an overview on the status of the use of CHT in plant systems. Attention was given to the research that suggested the use of CHT for sustainable crop productivity. PMID:27347928

  5. Chitosan Effects on Plant Systems.

    PubMed

    Malerba, Massimo; Cerana, Raffaella

    2016-01-01

    Chitosan (CHT) is a natural, safe, and cheap product of chitin deacetylation, widely used by several industries because of its interesting features. The availability of industrial quantities of CHT in the late 1980s enabled it to be tested in agriculture. CHT has been proven to stimulate plant growth, to protect the safety of edible products, and to induce abiotic and biotic stress tolerance in various horticultural commodities. The stimulating effect of different enzyme activities to detoxify reactive oxygen species suggests the involvement of hydrogen peroxide and nitric oxide in CHT signaling. CHT could also interact with chromatin and directly affect gene expression. Recent innovative uses of CHT include synthesis of CHT nanoparticles as a valuable delivery system for fertilizers, herbicides, pesticides, and micronutrients for crop growth promotion by a balanced and sustained nutrition. In addition, CHT nanoparticles can safely deliver genetic material for plant transformation. This review presents an overview on the status of the use of CHT in plant systems. Attention was given to the research that suggested the use of CHT for sustainable crop productivity. PMID:27347928

  6. Accumulation of Cd, Pb and Zn by 19 wetland plant species in constructed wetland.

    PubMed

    Liu, Jianguo; Dong, Yuan; Xu, Hai; Wang, Deke; Xu, Jiakuan

    2007-08-25

    Uptake and distribution of Cd, Pb and Zn by 19 wetland plant species were investigated with experiments in small-scale plot constructed wetlands, into which artificial wastewater dosed with Cd, Pb and Zn at concentrations of 0.5, 2.0 and 5.0mgl(-1) was irrigated. The results showed that the removal efficiency of Cd, Pb and Zn from the wastewater were more than 90%. Generally, there were tens differences among the 19 plant species in the concentrations and quantity accumulations of the heavy metals in aboveground part, underground part and whole plants. The distribution ratios into aboveground parts for the metals absorbed by plants varied also largely from about 30% to about 90%. All the plants accumulated, in one harvest, 19.85% of Cd, 22.55% of Pb and 23.75% of Zn that were added into the wastewater. Four plant species, e.g. Alternanthera philoxeroides, Zizania latifolia, Echinochloa crus-galli and Polygonum hydropiper, accumulated high amounts of Cd, Pb and Zn. Monochoria vaginalis was capable for accumulating Cd and Pb, Isachne globosa for Cd and Zn, and Digitaria sanguinalis and Fimbristylis miliacea for Zn. The results indicated that the plants, in constructed wetland for the treatment of wastewater polluted by heavy metals, can play important roles for removal of heavy metals through phytoextraction. Selection of plant species for use in constructed wetland will influence considerably removal efficiency and the function duration of the wetland. PMID:17353090

  7. Accumulation of Cd, Pb and Zn by 19 wetland plant species in constructed wetland.

    PubMed

    Liu, Jianguo; Dong, Yuan; Xu, Hai; Wang, Deke; Xu, Jiakuan

    2007-08-25

    Uptake and distribution of Cd, Pb and Zn by 19 wetland plant species were investigated with experiments in small-scale plot constructed wetlands, into which artificial wastewater dosed with Cd, Pb and Zn at concentrations of 0.5, 2.0 and 5.0mgl(-1) was irrigated. The results showed that the removal efficiency of Cd, Pb and Zn from the wastewater were more than 90%. Generally, there were tens differences among the 19 plant species in the concentrations and quantity accumulations of the heavy metals in aboveground part, underground part and whole plants. The distribution ratios into aboveground parts for the metals absorbed by plants varied also largely from about 30% to about 90%. All the plants accumulated, in one harvest, 19.85% of Cd, 22.55% of Pb and 23.75% of Zn that were added into the wastewater. Four plant species, e.g. Alternanthera philoxeroides, Zizania latifolia, Echinochloa crus-galli and Polygonum hydropiper, accumulated high amounts of Cd, Pb and Zn. Monochoria vaginalis was capable for accumulating Cd and Pb, Isachne globosa for Cd and Zn, and Digitaria sanguinalis and Fimbristylis miliacea for Zn. The results indicated that the plants, in constructed wetland for the treatment of wastewater polluted by heavy metals, can play important roles for removal of heavy metals through phytoextraction. Selection of plant species for use in constructed wetland will influence considerably removal efficiency and the function duration of the wetland.

  8. Removal mechanisms and plant species selection by bioaccumulative factors in surface flow constructed wetlands (CWs): In the case of triclosan.

    PubMed

    Zhao, Congcong; Xie, HuiJun; Xu, Jingtao; Zhang, Jian; Liang, Shuang; Hao, Jingcheng; Ngo, Huu Hao; Guo, Wenshan; Xu, Xiaoli; Wang, Qian; Wang, Jingmin

    2016-03-15

    Plants can bioaccumulate triclosan and bond with microbes and sediments in constructed wetlands (CWs) as well. However, little is known regarding the species-specific removal mechanism of CWs components and the selection of suitable wetland plant species for triclosan disposal. In this work, the use of bioaccumulation factors (BAFs) and biota to sediment accumulation factors (BSAFs) for choosing the best triclosan removal plant species was studied in laboratory-scale CWs. By the end of the experiment, over 80% of triclosan was removed and a specie-effect distribution was revealed in CWs with emergent, submerged and floating plants. By mass balance calculation, negative correlation between triclosan concentration in plants and degradation process was observed. The significant correlations between Log BSAFs values and triclosan concentration in plants or degradation contribution made it possible and reasonable in wetland plants selection. Introductions on plant species were provided considering the target removal process or regulation method. This work provided new information on plant species selection in CWs for triclosan removal or its emergency remediation by using bioaccumulative factors.

  9. Decreases in ammonia volatilization in response to greater plant diversity in microcosms of constructed wetlands

    NASA Astrophysics Data System (ADS)

    Luo, Bin; Ge, Ying; Han, Wenjuan; Fan, Xing; Ren, Yuan; Du, Yuanyuan; Shi, Mengmeng; Chang, Jie

    2016-10-01

    Ammonia volatilization from wastewaters with a high concentration of ammonium is a serious environmental and health problem. Constructed wetlands (CWs) are widely used for treating wastewater, and plant diversity clearly improves some functions of ecosystem such as nitrogen removal. However, whether plant diversity can affect ammonia volatilization from wastewater is still unknown. In this study, we conducted a microcosm experiment with different plant diversity treatments using four plant species. Results showed that, (1) ammonia volatilization decreased with increasing plant species richness; (2) ammonia volatilization from systems containing Rumex japonicus was lower than other systems; and (3) ammonia volatilization was affected more by species composition than species richness. This paper is the first to report that ammonia volatilization is reduced by plant diversity, and that some plant species combinations are important to reduce ammonia volatilization from CWs when treating wastewater.

  10. Assessment of modular construction for safety-related structures at advanced nuclear power plants

    SciTech Connect

    Braverman, J.; Morante, R.; Hofmayer, C.

    1997-03-01

    Modular construction techniques have been successfully used in a number of industries, both domestically and internationally. Recently, the use of structural modules has been proposed for advanced nuclear power plants. The objective in utilizing modular construction is to reduce the construction schedule, reduce construction costs, and improve the quality of construction. This report documents the results of a program which evaluated the proposed use of modular construction for safety-related structures in advanced nuclear power plant designs. The program included review of current modular construction technology, development of licensing review criteria for modular construction, and initial validation of currently available analytical techniques applied to concrete-filled steel structural modules. The program was conducted in three phases. The objective of the first phase was to identify the technical issues and the need for further study in order to support NRC licensing review activities. The two key findings were the need for supplementary review criteria to augment the Standard Review Plan and the need for verified design/analysis methodology for unique types of modules, such as the concrete-filled steel module. In the second phase of this program, Modular Construction Review Criteria were developed to provide guidance for licensing reviews. In the third phase, an analysis effort was conducted to determine if currently available finite element analysis techniques can be used to predict the response of concrete-filled steel modules.

  11. Microstructure of Concrete with Aggregates from Construction and Demolition Waste Recycling Plants.

    PubMed

    Bravo, Miguel; Santos Silva, António; de Brito, Jorge; Evangelista, Luís

    2016-02-01

    This paper intends to analyze the microstructure of concrete with recycled aggregates (RA) from construction and demolition waste from various Portuguese recycling plants. To that effect, several scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses were performed. Various concrete mixes were evaluated in order to analyze the influence of the RA's collection point and consequently of their composition on the mixes' characteristics. Afterward all the mixes were subjected to the capillary water absorption test in order to quantitatively evaluate their porosity. Results from the SEM/EDS analysis were compared with those from capillary water absorption test. The SEM/EDS analysis showed that the bond capacity of aggregates to the new cement paste is greatly influenced by the RA's nature. On the other hand, there was an increase in porosity with the incorporation of RA. PMID:26700727

  12. Microstructure of Concrete with Aggregates from Construction and Demolition Waste Recycling Plants.

    PubMed

    Bravo, Miguel; Santos Silva, António; de Brito, Jorge; Evangelista, Luís

    2016-02-01

    This paper intends to analyze the microstructure of concrete with recycled aggregates (RA) from construction and demolition waste from various Portuguese recycling plants. To that effect, several scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses were performed. Various concrete mixes were evaluated in order to analyze the influence of the RA's collection point and consequently of their composition on the mixes' characteristics. Afterward all the mixes were subjected to the capillary water absorption test in order to quantitatively evaluate their porosity. Results from the SEM/EDS analysis were compared with those from capillary water absorption test. The SEM/EDS analysis showed that the bond capacity of aggregates to the new cement paste is greatly influenced by the RA's nature. On the other hand, there was an increase in porosity with the incorporation of RA.

  13. Studies on the Effects of Gaseous Ions on Plant Growth

    PubMed Central

    Krueger, Albert P.; Beckett, J. C.; Andriese, Paul C.; Kotaka, Sadao

    1962-01-01

    Air pollutants seriously interfere with the maintenance of unipolar ionized atmospheres required in experimenting with the biological effects of gaseous ions. The construction and operation of an air purification unit designed to reduce air pollution to tolerable levels are described; it has functioned satisfactorily in conducting experiments with plants and animals. PMID:14459882

  14. Pathways regulating the removal of nitrogen in planted and unplanted subsurface flow constructed wetlands.

    PubMed

    Paranychianakis, Nikolaos V; Tsiknia, Myrto; Kalogerakis, Nicolas

    2016-10-01

    Single-stage constructed wetlands (CWs) are characterized by a low potential for N removal. Understanding the pathways regulating N cycling as well as their dependence on environmental variables might improve the potential of CWs for N removal and results in more accurate simulation tools. In this study we employed qPCR targeting marker functional genes (amoA, nirK, nirS, clade I and II nosZ) or microorganisms (anammox) regulating key pathways of N cycling to unravel their relative importance. Furthermore, the influence of plant species on treatment performance was studied. Our findings indicated nitrification-denitrification as the principal route of N removal in CWs, while anammox did not have a strong contribution. Evidence was also arisen that ammonia oxidizing archaea (AOA) contributed on NH3 oxidation. Overall, plant species had a weak effect on the abundance of N functional genes (amoA of AOA), but it strongly affected the performance of CWs in terms of N removal in the following order: unplanted < Phragmites communis < Typha latifolia. These findings suggest that plant species stimulate N removal by upregulating the rates that the responsible biochemical pathways operate, probably by increasing O2 supply. In addition, our study revealed differences in indicators linked to N2O emissions. The abundance of clade II nosZ genes remained low across the season scaling down a strong contribution in the reduction of the emitted N2O. The increasing ratios of nosZ/Σnir and nirS/nirK with the progress of season indicate a shift in the composition of denitrifiers towards strains with a lower genetic potential for N2O release. Similar trends were observed among the treatments but the mechanisms differed. The planted treatments stimulated an increase in the ΣnosZ/Σnir ratio, while the unplanted an increase in the nirS/nirK ratio. PMID:27379728

  15. Pathways regulating the removal of nitrogen in planted and unplanted subsurface flow constructed wetlands.

    PubMed

    Paranychianakis, Nikolaos V; Tsiknia, Myrto; Kalogerakis, Nicolas

    2016-10-01

    Single-stage constructed wetlands (CWs) are characterized by a low potential for N removal. Understanding the pathways regulating N cycling as well as their dependence on environmental variables might improve the potential of CWs for N removal and results in more accurate simulation tools. In this study we employed qPCR targeting marker functional genes (amoA, nirK, nirS, clade I and II nosZ) or microorganisms (anammox) regulating key pathways of N cycling to unravel their relative importance. Furthermore, the influence of plant species on treatment performance was studied. Our findings indicated nitrification-denitrification as the principal route of N removal in CWs, while anammox did not have a strong contribution. Evidence was also arisen that ammonia oxidizing archaea (AOA) contributed on NH3 oxidation. Overall, plant species had a weak effect on the abundance of N functional genes (amoA of AOA), but it strongly affected the performance of CWs in terms of N removal in the following order: unplanted < Phragmites communis < Typha latifolia. These findings suggest that plant species stimulate N removal by upregulating the rates that the responsible biochemical pathways operate, probably by increasing O2 supply. In addition, our study revealed differences in indicators linked to N2O emissions. The abundance of clade II nosZ genes remained low across the season scaling down a strong contribution in the reduction of the emitted N2O. The increasing ratios of nosZ/Σnir and nirS/nirK with the progress of season indicate a shift in the composition of denitrifiers towards strains with a lower genetic potential for N2O release. Similar trends were observed among the treatments but the mechanisms differed. The planted treatments stimulated an increase in the ΣnosZ/Σnir ratio, while the unplanted an increase in the nirS/nirK ratio.

  16. A Systems Engineering Framework for Design, Construction and Operation of the Next Generation Nuclear Plant

    SciTech Connect

    Edward J. Gorski; Charles V. Park; Finis H. Southworth

    2004-06-01

    Not since the International Space Station has a project of such wide participation been proposed for the United States. Ten countries, the European Union, universities, Department of Energy (DOE) laboratories, and industry will participate in the research and development, design, construction and/or operation of the fourth generation of nuclear power plants with a demonstration reactor to be built at a DOE site and operational by the middle of the next decade. This reactor will be like no other. The Next Generation Nuclear Plant (NGNP) will be passively safe, economical, highly efficient, modular, proliferation resistant, and sustainable. In addition to electrical generation, the NGNP will demonstrate efficient and cost effective generation of hydrogen to support the President’s Hydrogen Initiative. To effectively manage this multi-organizational and technologically complex project, systems engineering techniques and processes will be used extensively to ensure delivery of the final product. The technological and organizational challenges are complex. Research and development activities are required, material standards require development, hydrogen production, storage and infrastructure requirements are not well developed, and the Nuclear Regulatory Commission may further define risk-informed/performance-based approach to licensing. Detailed design and development will be challenged by the vast cultural and institutional differences across the participants. Systems engineering processes must bring the technological and organizational complexity together to ensure successful product delivery. This paper will define the framework for application of systems engineering to this $1.5B - $1.9B project.

  17. Potential effects of large linear pipeline construction on soil and vegetation in ecologically fragile regions.

    PubMed

    Xiao, Jun; Wang, Ya-Feng; Shi, Peng; Yang, Lei; Chen, Li-Ding

    2014-11-01

    Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant

  18. Potential effects of large linear pipeline construction on soil and vegetation in ecologically fragile regions.

    PubMed

    Xiao, Jun; Wang, Ya-Feng; Shi, Peng; Yang, Lei; Chen, Li-Ding

    2014-11-01

    Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant

  19. Seasonal nutrient uptake of plant biomass in a constructed wetland treating piggery wastewater effluent.

    PubMed

    Lee, S Y; Maniquiz, M C; Choi, J Y; Jeong, S M; Kim, L H

    2013-01-01

    The surface-flow constructed wetland (CW) located in Nonsan City, South Korea, and constructed as the final stage of a piggery wastewater treatment plant that aims to treat high nutrient content effluent during dry days and stormwater runoff during wet days was monitored from October 2008 to November 2011. This research investigated the seasonal nutrient uptake of plant biomass in the CW and nutrient concentration changes in each treatment region under monsoon and temperate climate conditions. Results showed that the mean total nitrogen removal during summer (June to August) was higher by 13% than in spring (March to May), while total phosphorus removal was higher by 22% in fall (September to November) than in winter (December to February). All plants in the CW reached their maximum biomass coverage and weight in summer and minimum growth in winter. The highest N and P content in plants occurred in September with 583.2 g/m(2) and August with 62.0 g/m(2), respectively. Based on the results, it is recommended that the harvesting of plants should be conducted during the time of the peak nutrient uptake and before the plants release the nutrient content back to the CW. The dependence of nutrient removal efficiency on plants is not so significant. In order to increase the nutrient removal rate by plant uptake, it is suggested that the treatment regions in the CW be covered by plants.

  20. Constructing wetlands: measuring and modeling feedbacks of oxidation processes between plants and clay-rich material

    NASA Astrophysics Data System (ADS)

    Saaltink, Rémon; Dekker, Stefan C.; Griffioen, Jasper; Wassen, Martin J.

    2016-04-01

    Interest is growing in using soft sediment as a building material in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here the option of dredging some of the clay-rich lake-bed sediment and using it to construct 10.000 ha of wetland will soon go under construction. Natural processes will be utilized during and after construction to accelerate ecosystem development. Knowing that plants can eco-engineer their environment via positive or negative biogeochemical plant-soil feedbacks, we conducted a six-month greenhouse experiment to identify the key biogeochemical processes in the mud when Phragmites australis is used as an eco-engineering species. We applied inverse biogeochemical modeling to link observed changes in pore water composition to biogeochemical processes. Two months after transplantation we observed reduced plant growth and shriveling as well as yellowing of foliage. The N:P ratios of plant tissue were low and were affected not by hampered uptake of N but by enhanced uptake of P. Plant analyses revealed high Fe concentrations in the leaves and roots. Sulfate concentrations rose drastically in our experiment due to pyrite oxidation; as reduction of sulfate will decouple Fe-P in reducing conditions, we argue that plant-induced iron toxicity hampered plant growth, forming a negative feedback loop, while simultaneously there was a positive feedback loop, as iron toxicity promotes P mobilization as a result of reduced conditions through root death, thereby stimulating plant growth and regeneration. Given these two feedback mechanisms, we propose that when building wetlands from these mud deposits Fe-tolerant species are used rather than species that thrive in N-limited conditions. The results presented in this study demonstrate the importance of studying the biogeochemical properties of the building material and the feedback mechanisms between plant and soil prior to finalizing the design of the eco-engineering project.

  1. Simple hand-held devices for the efficient infection of plants with viral-encoding constructs by particle bombardment.

    PubMed

    Gal-On, A; Meiri, E; Elman, C; Gray, D J; Gaba, V

    1997-02-01

    An efficient method for infection of plants with a cloned potyvirus by particle bombardment has been described (Gal-On et al., 1995). A simplified method is described now whereby a vaccuum chamber and helium propulsive gas are not required to achieve a high efficiency of infection. The new device-the 'HandGun'--is hand-held, and easily constructed from readily available materials. With this technique it is possible to bombard soft plants and seedings that do not survive particle bombardment by other devices. bombardment of C. pepo plants with a full length clone of zucchini yellow mosaic potyvirus results in approximately 100% infection at 100 pg cDNA per plant using air or helium to propel the microprojectiles. The HandGun is 10(5)-fold more efficient than mechanical inoculation. Tungsten and gold were found to be the most efficient materials tested for use as microprojectiles. Crude extracts of plasmids from E. coli were found to be effective, as well as column-purified cDNA. A functional, simple version of the HandGun--'the Blowpipe'--was also constructed, which does not require an electrically controlled valve. Plants can be inoculated with plant viruses from sap with the HandGun. PMID:9029535

  2. 32 CFR 644.486 - Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... constructed under emergency plant facilities (EPF) or similar contracts. 644.486 Section 644.486 National... Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or similar contracts. Procedure for the disposal of property constructed under a facilities contract on lands...

  3. Curvilinear effects of invasive plants on plant diversity: plant community invaded by Sphagneticola trilobata.

    PubMed

    Qi, Shan-Shan; Dai, Zhi-Cong; Zhai, De-Li; Chen, Si-Chong; Si, Chun-Can; Huang, Ping; Wang, Rui-Ping; Zhong, Qiong-Xin; Du, Dao-Lin

    2014-01-01

    The effects of invasive plants on the species diversity of plant communities are controversial, showing either a positive or negative linear relationship. Based on community data collected from forty 5 m×5 m plots invaded by Sphagneticola trilobata in eight cities across Hainan Island, China, we found S. trilobata decreased plant community diversity once its cover was beyond 10%. We demonstrated that the effects of invasive/native plants on the plant diversity of communities invaded by S. trilobata were curvilinear. These effects, which showed peaks under different degrees of vegetation cover, appeared not only for S. trilobata and all invasive plants, but also for all native plants. Invasive plants primarily had negative effects on plant diversity when they became abundant at a much lower cover level (less than 35%), compared with the native plants (over 60%). Thus, it is necessary to distinguish a range for assessing the effects of plants, especially invasive plants. Our results also confirmed that the invasion intensity of invasive alien plants increased with the intensity of local economic development. We highlight and further discuss the critical importance of curvilinear effects of biological invasion to provide ideas regarding the conservation of local biodiversity and the management of invasive plants.

  4. Curvilinear Effects of Invasive Plants on Plant Diversity: Plant Community Invaded by Sphagneticola trilobata

    PubMed Central

    Zhai, De-Li; Chen, Si-Chong; Si, Chun-Can; Huang, Ping; Wang, Rui-Ping; Zhong, Qiong-Xin; Du, Dao-Lin

    2014-01-01

    The effects of invasive plants on the species diversity of plant communities are controversial, showing either a positive or negative linear relationship. Based on community data collected from forty 5 m×5 m plots invaded by Sphagneticola trilobata in eight cities across Hainan Island, China, we found S. trilobata decreased plant community diversity once its cover was beyond 10%. We demonstrated that the effects of invasive/native plants on the plant diversity of communities invaded by S. trilobata were curvilinear. These effects, which showed peaks under different degrees of vegetation cover, appeared not only for S. trilobata and all invasive plants, but also for all native plants. Invasive plants primarily had negative effects on plant diversity when they became abundant at a much lower cover level (less than 35%), compared with the native plants (over 60%). Thus, it is necessary to distinguish a range for assessing the effects of plants, especially invasive plants. Our results also confirmed that the invasion intensity of invasive alien plants increased with the intensity of local economic development. We highlight and further discuss the critical importance of curvilinear effects of biological invasion to provide ideas regarding the conservation of local biodiversity and the management of invasive plants. PMID:25426856

  5. Curvilinear effects of invasive plants on plant diversity: plant community invaded by Sphagneticola trilobata.

    PubMed

    Qi, Shan-Shan; Dai, Zhi-Cong; Zhai, De-Li; Chen, Si-Chong; Si, Chun-Can; Huang, Ping; Wang, Rui-Ping; Zhong, Qiong-Xin; Du, Dao-Lin

    2014-01-01

    The effects of invasive plants on the species diversity of plant communities are controversial, showing either a positive or negative linear relationship. Based on community data collected from forty 5 m×5 m plots invaded by Sphagneticola trilobata in eight cities across Hainan Island, China, we found S. trilobata decreased plant community diversity once its cover was beyond 10%. We demonstrated that the effects of invasive/native plants on the plant diversity of communities invaded by S. trilobata were curvilinear. These effects, which showed peaks under different degrees of vegetation cover, appeared not only for S. trilobata and all invasive plants, but also for all native plants. Invasive plants primarily had negative effects on plant diversity when they became abundant at a much lower cover level (less than 35%), compared with the native plants (over 60%). Thus, it is necessary to distinguish a range for assessing the effects of plants, especially invasive plants. Our results also confirmed that the invasion intensity of invasive alien plants increased with the intensity of local economic development. We highlight and further discuss the critical importance of curvilinear effects of biological invasion to provide ideas regarding the conservation of local biodiversity and the management of invasive plants. PMID:25426856

  6. 32 CFR 644.486 - Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... constructed under emergency plant facilities (EPF) or similar contracts. 644.486 Section 644.486 National... Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or similar... defined to mean plant equipment which: (1) Is held under a facilities contract of the Department; (2)...

  7. Using game technologies to improve the safety of construction plant operations.

    PubMed

    Guo, Hongling; Li, Heng; Chan, Greg; Skitmore, Martin

    2012-09-01

    Many accidents occur world-wide in the use of construction plant and equipment, and safety training is considered by many to be one of the best approaches to their prevention. However, current safety training methods/tools are unable to provide trainees with the hands-on practice needed. Game technology-based safety training platforms have the potential to overcome this problem in a virtual environment. One such platform is described in this paper - its characteristics are analysed and its possible contribution to safety training identified. This is developed and tested by means of a case study involving three major pieces of construction plant, which successfully demonstrates that the platform can improve the process and performance of the safety training involved in their operation. This research not only presents a new and useful solution to the safety training of construction operations, but illustrates the potential use of advanced technologies in solving construction industry problems in general.

  8. Satellite observations of recent power plant construction in Inner Mongolia, China - article no. L15809

    SciTech Connect

    Zhang, Q.; Streets, D.G.; He, K.B.

    2009-08-15

    About 50% of the increase in China's NOx emissions since 2000 can be attributed to the construction of new power plants. We show that the newly added NOx emissions from new power plants in Inner Mongolia, China, were detected by the Ozone Monitoring Instrument (OMI) aboard NASA's Aura satellite. Increase rates of NO{sub 2} columns from OMI and NOx emissions from inventories are even in quantitative agreement in cases where new facilities are added to already-developed regions. This study confirms that the OMI products are quite capable of identifying the construction of large new emitting facilities through detection of their NOx emissions.

  9. Cholesterol-lowering effect of plant sterols.

    PubMed

    AbuMweis, Suhad S; Jones, Peter J H

    2008-12-01

    Plant sterols are plant components that have a chemical structure similar to cholesterol except for the addition of an extra methyl or ethyl group; however, plant sterol absorption in humans is considerably less than that of cholesterol. In fact, plant sterols reduce cholesterol absorption and thus reduce circulating levels of cholesterol. Earlier studies that have tested the efficacy of plant sterols as cholesterol-lowering agents incorporated plant sterols into fat spreads. Later on, plant sterols were added to other food matrices, including juices, nonfat beverages, milk and yogurt, cheese, meat, croissants and muffins, and cereal and chocolate bars. The beneficial physiologic effects of plant sterols could be further enhanced by combining them with other beneficial substances, such as olive and fish oils, fibers, and soy proteins, or with exercise. The addition of plant sterols to the diet is suggested by health experts as a safe and effective way to reduce the risk of coronary heart disease. PMID:18937893

  10. Phytoremediation of explosives contaminated ground waters by plant enzyme systems in constructed wetlands

    SciTech Connect

    Jackson, R.P. Jr.

    1995-12-31

    A plant enzyme system has successfully degraded the explosives TNT, RDX, and HMX to environmentally acceptable products during laboratory studies. The process has been further studied in the field in batch systems. The field results have been consistent with the laboratory findings. An artificial wetlands will be constructed to remediate explosives contaminated ground water at an Army ammunition plant. An overview of the phytoremediation program will be presented.

  11. Design and construction of an in-plant activation cassette for transgene expression and recombinant protein production in plants.

    PubMed

    Dugdale, Benjamin; Mortimer, Cara L; Kato, Maiko; James, Tess A; Harding, Robert M; Dale, James L

    2014-05-01

    Virus-based transgene expression systems have become particularly valuable for recombinant protein production in plants. The dual-module in-plant activation (INPACT) expression platform consists of a uniquely designed split-gene cassette incorporating the cis replication elements of Tobacco yellow dwarf geminivirus (TYDV) and an ethanol-inducible activation cassette encoding the TYDV Rep and RepA replication-associated proteins. The INPACT system is essentially tailored for recombinant protein production in stably transformed plants and provides both inducible and high-level transient transgene expression with the potential to be adapted to diverse crop species. The construction of a novel split-gene cassette, the inducible nature of the system and the ability to amplify transgene expression via rolling-circle replication differentiates this system from other DNA- and RNA-based virus vector systems used for stable or transient recombinant protein production in plants. Here we provide a detailed protocol describing the design and construction of a split-gene INPACT cassette, and we highlight factors that may influence optimal activation and amplification of gene expression in transgenic plants. By using Nicotiana tabacum, the protocol takes 6-9 months to complete, and recombinant proteins expressed using INPACT can accumulate to up to 10% of the leaf total soluble protein.

  12. Sulfate removal and sulfur transformation in constructed wetlands: The roles of filling material and plant biomass.

    PubMed

    Chen, Yi; Wen, Yue; Zhou, Qi; Huang, Jingang; Vymazal, Jan; Kuschk, Peter

    2016-10-01

    Sulfate in effluent is a challenging issue for wastewater reuse around the world. In this study, sulfur (S) removal and transformation in five batch constructed wetlands (CWs) treating secondary effluent were investigated. The results showed that the presence of the plant cattail (Typha latifolia) had little effect on sulfate removal, while the carbon-rich litter it generated greatly improved sulfate removal, but with limited sulfide accumulation in the pore-water. After sulfate removal, most of the S was deposited with the valence states S (-II) and S (0) on the iron-rich gravel surface, and acid volatile sulfide was the main S sink in the litter-added CWs. High-throughput pyrosequencing revealed that sulfate-reducing bacteria (i.e. Desulfobacter) and sulfide-oxidizing bacteria (i.e. Thiobacillus) were dominant in the litter-added CWs, which led to a sustainable S cycle between sulfate and sulfide. Overall, this study suggests that recycling plant litter and iron-rich filling material in CWs gives an opportunity to utilize the S in the wastewater as both an electron acceptor for sulfate reduction and as an electron donor for nitrate reduction coupled with sulfide oxidation. This leads to the simultaneous removal of sulfate, nitrate, and organics without discharging toxic sulfide into the receiving water body. PMID:27423407

  13. Sulfate removal and sulfur transformation in constructed wetlands: The roles of filling material and plant biomass.

    PubMed

    Chen, Yi; Wen, Yue; Zhou, Qi; Huang, Jingang; Vymazal, Jan; Kuschk, Peter

    2016-10-01

    Sulfate in effluent is a challenging issue for wastewater reuse around the world. In this study, sulfur (S) removal and transformation in five batch constructed wetlands (CWs) treating secondary effluent were investigated. The results showed that the presence of the plant cattail (Typha latifolia) had little effect on sulfate removal, while the carbon-rich litter it generated greatly improved sulfate removal, but with limited sulfide accumulation in the pore-water. After sulfate removal, most of the S was deposited with the valence states S (-II) and S (0) on the iron-rich gravel surface, and acid volatile sulfide was the main S sink in the litter-added CWs. High-throughput pyrosequencing revealed that sulfate-reducing bacteria (i.e. Desulfobacter) and sulfide-oxidizing bacteria (i.e. Thiobacillus) were dominant in the litter-added CWs, which led to a sustainable S cycle between sulfate and sulfide. Overall, this study suggests that recycling plant litter and iron-rich filling material in CWs gives an opportunity to utilize the S in the wastewater as both an electron acceptor for sulfate reduction and as an electron donor for nitrate reduction coupled with sulfide oxidation. This leads to the simultaneous removal of sulfate, nitrate, and organics without discharging toxic sulfide into the receiving water body.

  14. Design and construction of coke battery 1A at Radlin coke plant, Poland

    SciTech Connect

    A.M. Kravchenko; D.P. Yarmoshik; V.B. Kamenyuka; G.E. Kos'kova; N.I. Shkol'naya; V.V. Derevich; A.S. Grankin

    2009-07-15

    In the design and construction of coke battery 1A at Radlin coke plant (Poland), coking of rammed coke with a stationary system was employed for the first time. The coke batteries are grouped in blocks. Safety railings are provided on the coke and machine sides of the maintenance areas.

  15. 75 FR 38042 - Specifications and Drawings for Construction of Direct Buried Plant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ..., at 75 FR 32313 regarding the request for comments on revising RUS Bulletin 1753F-150, Specifications... document FR Doc. 2010-12830 beginning on page 32313 in the issue of June 8, 2010, make the following... Construction of Direct Buried Plant AGENCY: Rural Utilities Service, USDA. ACTION: Proposed Rule;...

  16. Mixed Waste Management Facility (MWMF) closure, Savannah River Plant: Clay cap test section construction report

    SciTech Connect

    Not Available

    1988-02-26

    This report contains appendices 3 through 6 for the Clay Cap Test Section Construction Report for the Mixed Waste Management Facility (MWMF) closure at the Savannah River Plant. The Clay Cap Test Program was conducted to evaluate the source, lab. permeability, in-situ permeability, and compaction characteristics, representative of kaolin clays from the Aiken, South Carolina vicinity. (KJD)

  17. H-coal pilot plant. Phase II. Construction. Phase III. Operation. Annual report No. 3

    SciTech Connect

    Not Available

    1981-02-04

    At the request of DOE Oak Ridge, ASFI agreed to assume responsibility for completion of Plant construction in December, 1979, at which time Badger Plants' on-site work was ended. This construction effort consisted of electric heat tracing and insulation of piping and instrumentation. At the close of the reporting period the work was completed, or was projected to be completed, within the ASFI budgeted amounts and by dates that will not impact Plant operations. Engineering design solutions were completed for problems encountered with such equipment as the High Pressure Letdown Valves; Slurry Block Valves; Slurry Pumps; the Bowl Mill System; the Dowtherm System; and the Ebullating Pump. A Corrosion Monitoring Program was established. With the exception of Area 500, the Antisolvent Deashing Unit, all operating units were commissioned and operated during the reporting period. Coal was first introduced into the Plant on May 29, 1980, with coal operations continuing periodically through September 30, 1980. The longest continuous coal run was 119 hours. A total of 677 tons of Kentucky No. 11 Coal were processed during the reporting period. The problems encountered were mechanical, not process, in nature. Various Environmental and Health programs were implemented to assure worker safety and protection and to obtain data from Plant operations for scientific analysis. These comprehensive programs will contribute greatly in determining the acceptability of long term H-Coal Plant operations.

  18. The Comparative Effect of Individually-Constructed vs. Collaboratively-Constructed Computer-Based Concept Maps

    ERIC Educational Resources Information Center

    Kwon, So Young; Cifuentes, Lauren

    2009-01-01

    The researchers investigated the comparative effects of individually-constructed and collaboratively-constructed computer-based concept mapping on middle school science concept learning. One hundred and sixty one students completed the entire study. Using prior science performance scores to assure equivalence of student achievement across groups,…

  19. Influences of plant type on bacterial and archaeal communities in constructed wetland treating polluted river water.

    PubMed

    Long, Yan; Yi, Hao; Chen, Sili; Zhang, Zhengke; Cui, Kai; Bing, Yongxin; Zhuo, Qiongfang; Li, Bingxin; Xie, Shuguang; Guo, Qingwei

    2016-10-01

    Both bacteria and archaeal communities can play important roles in biogeochemical processes in constructed wetland (CW) system. However, the influence of plant type on microbial community in surface water CW remains unclear. The present study investigated bacterial and archaeal communities in five surface water CW systems with different plant species. The abundance, richness, and diversity of both bacterial and archaeal communities considerably differed in these five CW systems. Compared with the other three CW systems, the CW systems planted with Vetiveria zizanioides or Juncus effusus L. showed much higher bacterial abundance but lower archaeal abundance. Bacteria outnumbered archaea in each CW system. Moreover, the CW systems planted with V. zizanioides or J. effusus L. had relatively lower archaeal but higher bacterial richness and diversity. In each CW system, bacterial community displayed much higher richness and diversity than archaeal community. In addition, a remarkable difference of both bacterial and archaeal community structures was observed in the five studied CW systems. Proteobacteria was the most abundant bacterial group (accounting for 33-60 %). Thaumarchaeota organisms (57 %) predominated in archaeal communities in CW systems planted with V. zizanioides or J. effusus L., while Woesearchaeota (23 or 24 %) and Euryarchaeota (23 or 15 %) were the major archaeal groups in CW systems planted with Cyperus papyrus or Canna indica L. Archaeal community in CW planted with Typha orientalis Presl was mainly composed of unclassified archaea. Therefore, plant type exerted a considerable influence on microbial community in surface water CW system. PMID:27392623

  20. Innovative reuse of concrete slurry waste from ready-mixed concrete plants in construction products.

    PubMed

    Xuan, Dongxing; Zhan, Baojian; Poon, Chi Sun; Zheng, Wei

    2016-07-15

    Concrete slurry waste (CSW) is generated from ready-mixed concrete plants during concrete production and is classified as a corrosive hazardous material. If it is disposed of at landfills, it would cause detrimental effects for our surrounding environment and ecosystems due to its high pH value as well as heavy metal contamination and accumulation. A new method in this study has been introduced to effectively reuse CSW in new construction products. In this method, the calcium-silicate rich CSW in the fresh state was considered as a cementitious paste as well as a CO2 capture medium. The experimental results showed that the pH values of the collected CSWs stored for 28 days ranged from 12.5 to 13.0 and a drastic decrease of pH value was detected after accelerated mineral carbonation. The theoretically calculated CO2 sequestration extent of CSWs was from 27.05% to 31.23%. The practical water to solid ratio in the fresh CSW varied from 0.76 to 1.12, which had a significant impact on the compressive strength of the mixture with CSWs. After subjecting to accelerated mineral carbonation, rapid initial strength development and lower drying shrinkage for the prepared concrete mixture were achieved. PMID:27016667

  1. Innovative reuse of concrete slurry waste from ready-mixed concrete plants in construction products.

    PubMed

    Xuan, Dongxing; Zhan, Baojian; Poon, Chi Sun; Zheng, Wei

    2016-07-15

    Concrete slurry waste (CSW) is generated from ready-mixed concrete plants during concrete production and is classified as a corrosive hazardous material. If it is disposed of at landfills, it would cause detrimental effects for our surrounding environment and ecosystems due to its high pH value as well as heavy metal contamination and accumulation. A new method in this study has been introduced to effectively reuse CSW in new construction products. In this method, the calcium-silicate rich CSW in the fresh state was considered as a cementitious paste as well as a CO2 capture medium. The experimental results showed that the pH values of the collected CSWs stored for 28 days ranged from 12.5 to 13.0 and a drastic decrease of pH value was detected after accelerated mineral carbonation. The theoretically calculated CO2 sequestration extent of CSWs was from 27.05% to 31.23%. The practical water to solid ratio in the fresh CSW varied from 0.76 to 1.12, which had a significant impact on the compressive strength of the mixture with CSWs. After subjecting to accelerated mineral carbonation, rapid initial strength development and lower drying shrinkage for the prepared concrete mixture were achieved.

  2. Temperature Profile Measurements in a Newly Constructed 30-Stage 5 cm Centrifugal Contactor pilot Plant

    SciTech Connect

    Troy G. Garn; Dave H. Meikrantz; Mitchell R. Greenhalgh; Jack D. Law

    2008-09-01

    An annular centrifugal contactor pilot plant incorporating 30 stages of commercial 5 cm CINC V-02 units has been built and operated at INL during the past year. The pilot plant includes an automated process control and data acquisitioning system. The primary purpose of the pilot plant is to evaluate the performance of a large number of inter-connected centrifugal contactors and obtain temperature profile measurements within a 30-stage cascade. Additional solvent extraction flowsheet testing using stable surrogates is also being considered. Preliminary hydraulic testing was conducted with all 30 contactors interconnected for continuous counter-current flow. Hydraulic performance and system operational tests were conducted successfully but with higher single-stage rotor speeds found necessary to maintain steady interstage flow at flowrates of 1 L/min and higher. Initial temperature profile measurements were also completed in this configuration studying the performance during single aqueous and two-phase counter-current flow at ambient and elevated inlet solution temperatures. Temperature profile testing of two discreet sections of the cascade required additional feed and discharge connections. Lamp oil, a commercially available alkane mixture of C14 to C18 chains, and tap water adjusted to pH 2 were the solution feeds for all the testing described in this report. Numerous temperature profiles were completed using a newly constructed 30-stage centrifugal contactor pilot plant. The automated process control and data acquisition system worked very well throughout testing. Temperature data profiles for an array of total flowrates (FT) and contactor rpm values for both single-phase and two-phase systems have been collected with selected profiles and comparisons reported. Total flowrates (FT) ranged from 0.5-1.4 L/min with rotor speeds from 3500-4000 rpm. Solution inlet temperatures ranging from ambient up to 50° C were tested. Ambient temperature testing shows that a

  3. Construction of plants resistant to TYLCV by using artificial zinc-finger proteins.

    PubMed

    Koshino-Kimura, Yoshihiro; Takenaka, Kosuke; Domoto, Fumiya; Ohashi, Masayoshi; Miyazaki, Toshihide; Aoyama, Yasuhiro; Sera, Takashi

    2009-01-01

    Previously, we have demonstrated that plant DNA virus replication could be inhibited in Arabidopsis thaliana by using an artificial zinc-finger protein (AZP) and created AZP-based transgenic A. thaliana resistant to DNA virus infection. Here we apply the AZP technology to tomato yellow leaf curl virus (TYLCV) causing serious damage to an important agricultural crop, tomato. An AZP was designed to block binding of the TYLCV replication protein (Rep) to the replication origin. The designed AZP had much higher affinities towards the replication origin than did the Rep, and efficiently blocked Rep binding in vitro. The AZP gene was then introduced into a plant genome with the help of Agrobacterium tumefaciens to generate the transgenic plants. The current status of the construction of the AZP-expressing transgenic plants will be reported.

  4. Notice of Construction for the Magnesium Hydroxide Precipitation Process at the Plutonium Finishing Plant (PFP)

    SciTech Connect

    JANSKY, M.T.

    1999-12-01

    The following description and any attachments and references are provided to the Washington State Department of Health (WDOH), Division of Radiation Protection, Air Emissions & Defense Waste (WAC) 246-247, Radiation Protection-Air Emissions. The WAC 246-247-060, ''Applications, registration, and licensing'', states ''This section describes the information requirements for approval to construct, modify, and operate an emission unit. Any NOC requires the submittal of information listed in Appendix A.'' Appendix A (WAC 246-247-1 10) lists the requirements that must be addressed. Additionally, the following description, attachments and references are provided to the US Environmental Protection Agency (EPA) as an NOC, in accordance with Title 40, Code of Federal Regulations (CFR), Part 61, ''National Emission Standards for Hazardous Air Pollutants.'' The information required for submittal to the EPA is specified in 40 CFR 61.07. The potential emissions from this activity are estimated to provide greater than 0.1 millirem per year total effective dose equivalent (TEDE) to the hypothetical offsite maximally exposed individual (MEI), and commencement is needed within a short time. Therefore, this application also is intended to provide notification of the anticipated date of initial startup in accordance with the requirement listed in 40 CFR 61.09(a)(1), and it is requested that approval of this application also will constitute EPA acceptance of this initial startup notification. Written notification of the actual date of initial startup, in accordance with the requirement listed in 40 CFR 61.09(a)(2) will be provided at a later date. This NOC covers the activities associated with the Construction and operation activities involving the magnesium hydroxide precipitation process of plutonium solutions within the Plutonium Finishing Plant (PFP).

  5. Secondary effects of glyphosate on plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glyphosate is a unique herbicide with interesting secondary effects. Unfortunately, some have assumed that the secondary effects that occur in glyphosate-susceptible plants treated with glyphosate, such as altered mineral nutrition, reduced phenolic compound production and pathogen resistance, also ...

  6. Construction and operation of an industrial solid waste landfill at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    SciTech Connect

    1995-10-01

    The US Department of Energy (DOE), Office of Waste Management, proposes to construct and operate a solid waste landfill within the boundary of the Portsmouth Gaseous Diffusion Plant (PORTS), Piketon, Ohio. The purpose of the proposed action is to provide PORTS with additional landfill capacity for non-hazardous and asbestos wastes. The proposed action is needed to support continued operation of PORTS, which generates non-hazardous wastes on a daily basis and asbestos wastes intermittently. Three alternatives are evaluated in this environmental assessment (EA): the proposed action (construction and operation of the X-737 landfill), no-action, and offsite shipment of industrial solid wastes for disposal.

  7. Treatment of domestic wastewater by vertical flow constructed wetland planted with umbrella sedge and Vetiver grass.

    PubMed

    Kantawanichkul, Suwasa; Sattayapanich, Somsiri; van Dien, Frank

    2013-01-01

    The aim of this study was to investigate the efficiency of wastewater treatment by vertical flow constructed wetland systems under different hydraulic loading rates (HLR). The comparison of two types of plants, Cyperus alternifolius (Umbrella sedge) and Vetiveria zizanioides (Vetiver grass), was also conducted. In this study, six circular concrete tanks (diameter 0.8 m) were filled with fine sand and gravel to the depth of 1.23 m. Three tanks were planted with Umbrella sedge and the other three tanks were planted with Vetiver grass. Settled domestic wastewater from Chiang Mai University (chemical oxygen demand (COD), NH4(+)-N and suspended solids (SS) of 127.1, 27.4 and 29.5 mg/L on average, respectively) was intermittently applied for 45 min and rested for 3 h 15 min. The HLR of each tank was controlled at 20, 29 and 40 cm/d. It was found that the removal efficiency of the Umbrella sedge systems was higher than the Vetiver grass systems for every parameter, and the lowest HLR provided the maximum treatment efficiency. The removal efficiency of COD and nitrogen in terms of total Kjeldahl nitrogen (TKN) was 76 and 65% at 20 cm/d HLR for Umbrella sedge compared to only 67 and 56% for Vetiver grass. Nitrogen accumulation in plant biomass was also higher in Umbrella sedge than in Vetiver grass in every HLR. Umbrella sedge was thus proved to be a suitable constructed wetland plant in tropical climates.

  8. Treatment of domestic wastewater by vertical flow constructed wetland planted with umbrella sedge and Vetiver grass.

    PubMed

    Kantawanichkul, Suwasa; Sattayapanich, Somsiri; van Dien, Frank

    2013-01-01

    The aim of this study was to investigate the efficiency of wastewater treatment by vertical flow constructed wetland systems under different hydraulic loading rates (HLR). The comparison of two types of plants, Cyperus alternifolius (Umbrella sedge) and Vetiveria zizanioides (Vetiver grass), was also conducted. In this study, six circular concrete tanks (diameter 0.8 m) were filled with fine sand and gravel to the depth of 1.23 m. Three tanks were planted with Umbrella sedge and the other three tanks were planted with Vetiver grass. Settled domestic wastewater from Chiang Mai University (chemical oxygen demand (COD), NH4(+)-N and suspended solids (SS) of 127.1, 27.4 and 29.5 mg/L on average, respectively) was intermittently applied for 45 min and rested for 3 h 15 min. The HLR of each tank was controlled at 20, 29 and 40 cm/d. It was found that the removal efficiency of the Umbrella sedge systems was higher than the Vetiver grass systems for every parameter, and the lowest HLR provided the maximum treatment efficiency. The removal efficiency of COD and nitrogen in terms of total Kjeldahl nitrogen (TKN) was 76 and 65% at 20 cm/d HLR for Umbrella sedge compared to only 67 and 56% for Vetiver grass. Nitrogen accumulation in plant biomass was also higher in Umbrella sedge than in Vetiver grass in every HLR. Umbrella sedge was thus proved to be a suitable constructed wetland plant in tropical climates. PMID:24056433

  9. Effects of herbivores on grassland plant diversity.

    PubMed

    Olff, H; Ritchie, M E

    1998-07-01

    The role of herbivores in controlling plant species richness is a critical issue in the conservation and management of grassland biodiversity. Numerous field experiments in grassland plant communities show that herbivores often, but not always, increase plant diversity. Recent work suggests that the mechanisms of these effects involve alteration of local colonization of species from regional species pools or local extinction of species, and recent syntheses and models suggest that herbivore effects on plant diversity should vary across environmental gradients of soil fertility and precipitation.

  10. Effects of perchlorate on growth of four wetland plants and its accumulation in plant tissues.

    PubMed

    He, Hongzhi; Gao, Haishuo; Chen, Guikui; Li, Huashou; Lin, Hai; Shu, Zhenzhen

    2013-10-01

    Perchlorate contamination in water is of concern because of uncertainties about toxicity and health effects, impact on ecosystems, and possible indirect exposure pathways to humans. Therefore, it is very important to investigate the ecotoxicology of perchlorate and to screen plant species for phytoremediation. Effects of perchlorate (20, 200, and 500 mg/L) on the growth of four wetland plants (Eichhornia crassipes, Acorus calamus L., Thalia dealbata, and Canna indica) as well as its accumulation in different plant tissues were investigated through water culture experiments. Twenty milligrams per liter of perchlorate had no significant effects on height, root length, aboveground part weight, root weight, and oxidizing power of roots of four plants, except A. calamus, and increasing concentrations of perchlorate showed that out of the four wetland plants, only A. calamus had a significant (p<0.05) dose-dependent decrease in these parameters. When treated with 500 mg/L perchlorate, these parameters and chlorophyll content in the leaf of plants showed significant decline contrasted to control groups, except the root length of E. crassipes and C. indica. The order of inhibition rates of perchlorate on root length, aboveground part weight and root weight, and oxidizing power of roots was: A. calamus > C. indica > T. dealbata > E. crassipes and on chlorophyll content in the leaf it was: A. calamus > T. dealbata > C. indica > E. crassipes. The higher the concentration of perchlorate used, the higher the amount of perchlorate accumulation in plants. Perchlorate accumulation in aboveground tissues was much higher than that in underground tissues and leaf was the main tissue for perchlorate accumulation. The order of perchlorate accumulation content and the bioconcentration factor in leaf of four plants was: E. crassipes > C. indica > T. dealbata > A. calamus. Therefore, E. crassipes might be an ideal plant with high tolerance ability and accumulation ability for constructing

  11. Effects of perchlorate on growth of four wetland plants and its accumulation in plant tissues.

    PubMed

    He, Hongzhi; Gao, Haishuo; Chen, Guikui; Li, Huashou; Lin, Hai; Shu, Zhenzhen

    2013-10-01

    Perchlorate contamination in water is of concern because of uncertainties about toxicity and health effects, impact on ecosystems, and possible indirect exposure pathways to humans. Therefore, it is very important to investigate the ecotoxicology of perchlorate and to screen plant species for phytoremediation. Effects of perchlorate (20, 200, and 500 mg/L) on the growth of four wetland plants (Eichhornia crassipes, Acorus calamus L., Thalia dealbata, and Canna indica) as well as its accumulation in different plant tissues were investigated through water culture experiments. Twenty milligrams per liter of perchlorate had no significant effects on height, root length, aboveground part weight, root weight, and oxidizing power of roots of four plants, except A. calamus, and increasing concentrations of perchlorate showed that out of the four wetland plants, only A. calamus had a significant (p<0.05) dose-dependent decrease in these parameters. When treated with 500 mg/L perchlorate, these parameters and chlorophyll content in the leaf of plants showed significant decline contrasted to control groups, except the root length of E. crassipes and C. indica. The order of inhibition rates of perchlorate on root length, aboveground part weight and root weight, and oxidizing power of roots was: A. calamus > C. indica > T. dealbata > E. crassipes and on chlorophyll content in the leaf it was: A. calamus > T. dealbata > C. indica > E. crassipes. The higher the concentration of perchlorate used, the higher the amount of perchlorate accumulation in plants. Perchlorate accumulation in aboveground tissues was much higher than that in underground tissues and leaf was the main tissue for perchlorate accumulation. The order of perchlorate accumulation content and the bioconcentration factor in leaf of four plants was: E. crassipes > C. indica > T. dealbata > A. calamus. Therefore, E. crassipes might be an ideal plant with high tolerance ability and accumulation ability for constructing

  12. 49 CFR 240.5 - Preemptive effect and construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Preemptive effect and construction. 240.5 Section 240.5 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 240.5 Preemptive effect and construction. (a) Under 49 U.S.C. 20106, issuance of the regulations...

  13. Effect of microgravity on plant growth

    NASA Technical Reports Server (NTRS)

    Lewis, Norman G.

    1994-01-01

    The overall goal of this research is to determine the effect of microgravity proper on plant growth (metabolism and cell wall formation). In addressing this goal, the work conducted during this grant period was divided into three components: analyses of various plant tissues previously grown in space aboard MIR Space Station; analyses of wheat tissues grown on Shuttle flight STS-51; and Phenylpropanoid metabolism and plant cell wall synthesis (earth-based investigations).

  14. Design solutions for water treatment plants constructed on the basis of membrane technologies

    NASA Astrophysics Data System (ADS)

    Panteleev, A. A.; Ryabchikov, B. E.; Zhadan, A. V.; Khoruzhii, O. V.

    2012-07-01

    Two process circuits for demineralizing makeup water for power units at thermal power stations are considered. One of them is constructed on the basis of a combined plant comprising reverse-osmosis and ion-exchange apparatuses and the other comprises reverse-osmosis and electric deionization apparatuses. The considered circuits are analyzed by way of comparing them with the traditional chemical water demineralization system. Advantages and drawbacks of the new technologies for treating natural water are pointed out.

  15. Mixed Waste Management Facility (MWMF) closure, Savannah River Plant: Clay cap test section construction report

    SciTech Connect

    Not Available

    1988-02-26

    This report contains appendix 2 for the Clay Cap Test Section Construction Report for the Mixed Waste Management Facility (MWMF) closure at the Savannah River Plant. The Clay Cap Test Program was conducted to evaluate the source, Laboratory permeability, and compaction characteristics representative of Kaolin clays from the aiken, South Carolina vicinity. Included in this report are daily field reports Nos. 1 to 54. (KJD)

  16. Novel solar tower structure to lower plant cost and construction risk

    NASA Astrophysics Data System (ADS)

    Peterseim, J. H.; White, S.; Hellwig, U.

    2016-05-01

    In recent times the interest in solar tower power plants is increasing with various plants being built in the last years and currently under construction, e.g. Ivanpah and Crescent Dunes in the US and Khi Solar One in South Africa. The higher cycle efficiency leads to lower levelised cost of electricity. However, further cost reductions are required and this paper compares a novel and patented solar tower structure with a conventional concrete tower. The novel solar tower design is cable-stayed which has the benefit that the cables absorb a large part of the wind and buckling loads. A tower that has to cope with fewer wind and buckling forces can have a significantly smaller diameter than a concrete tower, which enables workshop manufacture, sea and road transport, and rapid on-site installation. The case study provided in this paper finds that the tower area affected by wind can be reduced by up to 45%, installation time shortened by up to 66%, and tower cost by 20-40%. The novel design allows the construction and transport of the solar tower in few large modules, which are pre-manufactured including piping, cables, platform, ladders etc. The few modules can be assembled and installed rapidly not only lowering plant cost and construction time but also project risk.

  17. Effects of salinity on treatment of municipal wastewater by constructed mangrove wetland microcosms.

    PubMed

    Wu, Yan; Tam, N F Y; Wong, M H

    2008-01-01

    The effects of salinity on the removal of dissolved organic carbon and nutrients from municipal wastewater by constructed mangrove microcosms planted with Aegiceras corniculatum were investigated. During the four-month wastewater treatment, the treatment efficiency was reduced by high salinity, and the removal percentages of dissolved organic carbon, ammonia-N and inorganic N dropped from 91% to 71%, from 98% to 83% and from 78% to 56%, respectively, with salinity increasing from 0 to 30 parts per thousands (ppt). In spite of such inhibition at high salinity, 100% of the effluents discharge from the constructed mangrove microcosms still complied with the discharge standards set by the Hong Kong Government for Coastal Water Control Zones. These results suggested that constructed mangrove wetland treatment systems were promising to effectively treat municipal wastewater, even those with high salinity. In addition, the denitrification potential in soil was found to be retarded by the high salinity while mangrove plants grew best at 15 ppt salinity condition.

  18. [Construction of a vector conferring herbicide and pest resistance in tobacco plant].

    PubMed

    Xie, Long-Xu; Xu, Pei-Lin; Nie, Yan-Fang; Tian, Ying-Chuan

    2003-09-01

    A binary plant expression vector, pCM12-slm, carrying the aroAM12 mutant gene encoding bacterial 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) and the Bts1m recombinant gene consisting of 331 N-terminal amino acids of CryIAc and 284 C-terminal amino acids of CryIAb has been constructed. The truncated Bts1 gene was fused with the PR1b signal peptide sequence and expressed in tobacco plants under the control of 2E-CaMV35S promoter and the omega (omega) translation enhancer sequence from tobacco mosaic virus. The mutant aroAM12 was fused with the transit sequence of tobacco EPSPS and expressed in tobacco plants under the control of the CaMV35S promoter. Tobacco leaves were transformed with Agrobacterium tumefaciens LBA4404 harboring the pCM12-slm plasmid, and the transgenic plants were selected directly on medium containing the herbicide. Forty glyphosate resistant plants were regenerated, with a transformation frequency of 27%. Transgenic plants were initially assessed for glyphosate resistance by placing leaf discs on shoot induction media containing the herbicide. Rooted plantlets, propagated from selected transgenic tobacco, were transferred to soil in a greenhouse and tested for glyphosate resistance by spraying them with Roundup at a commercial recommended dose. The glyphosate resistance assay indicated that all the transgenic plants showed highly resistant to the herbicide. The PCR assay showed that the aroAM12 gene was present in all of the 40 T0 transfer plants, and Bts1m genes present in 28 of 40 of the transgenic plants. Southern blot analysis further confirmed that the copy number of the transgenes varied from one to three copies in different transgenic plants. Northern blot and immunodot blot showed that the aroAM12 and Bts1m genes were expressed at the transcription and translation levels. Transgenic plants containing both the aroA M12 and Bts1m genes were further assessed for insect resistance. Tobacco leaves of T0 transgenic plants were infested

  19. Geopolymerisation of silt generated from construction and demolition waste washing plants.

    PubMed

    Lampris, C; Lupo, R; Cheeseman, C R

    2009-01-01

    Recycling plants that size, sort and wash construction and demolition waste can produce high quality aggregate. However, they also produce up to 80ton per hour of filter cake waste containing fine (<63mum) silt particles that is classified as inert waste and normally landfilled. This research investigated the potential to form geopolymers containing silt, which would allow this problematic waste to be beneficially reused as aggregate. This would significantly improve the economic viability of recycling plants that wash wastes. Silt filter cakes have been collected from a number of aggregate washing plants operating in the UK. These were found to contain similar aluminosilicate crystalline phases. Geopolymer samples were produced using silt and silt mixed with either metakaolin or pulverised fuel ash (PFA). Silt geopolymers cured at room temperature had average 7-day compressive strengths of 18.7MPa, while partial substitution of silt by metakaolin or PFA increased average compressive strengths to 30.5 and 21.9MPa, respectively. Curing specimens for 24h at 105 degrees C resulted in a compressive strength of 39.7MPa and microstructural analysis confirmed the formation of dense materials. These strengths are in excess of those required for materials to be used as aggregate, particularly in unbound applications. The implications of this research for the management of waste silt at construction and demolition waste washing plants are discussed.

  20. Frequency and quality of radiation monitoring of construction workers at two gaseous diffusion plants.

    PubMed

    Bingham, Eula; Ringen, Knut; Dement, John; Cameron, Wilfrid; McGowan, William; Welch, Laura; Quinn, Patricia

    2006-09-01

    Construction workers were and are considered temporary workers at many construction sites. Since World War II, large numbers of construction workers were employed at U.S. Department of Energy nuclear weapons sites for periods ranging from a few days to over 30 years. These workers performed tasks during new construction and maintenance, repair, renovation, and demolition of existing facilities. Such tasks may involve emergency situations, and may entail opportunities for significant radiation exposures. This paper provides data from interviews with more than 750 construction workers at two gaseous diffusion plants (GDPs) at Paducah, Kentucky, and Portsmouth, Ohio regarding radiation monitoring practices. The aim was to determine the extent to which workers believed they were monitored during tasks involving potential radiation exposures. The adequacy of monitoring practices is important for two reasons: (a) Protecting workers from exposures: Construction workers were employed by sub-contractors, and may frequently been excluded from safety and health programs provided to permanent employees; and (b) Supporting claims for compensation: The Energy Employees Occupational Illness Compensation Program Act (EEOICPA) requires dose reconstruction of radiation exposures for most workers who file a claim regarding cancer. The use of monitoring data for radiation to qualify a worker means that there should be valid and complete monitoring during the work time at the various nuclear plants or workers may be unfairly denied compensation. The worker interviews from Paducah and Portsmouth were considered especially useful because these sites were designated as Special Exposure Cohorts (SECs) and the workers did not have to have a dose reconstruction to qualify for compensation for most cancers. Therefore, their responses were less likely to be affected by compensation concerns. Interview questions included asking for information regarding whether monitoring was performed, how

  1. Nitrogen and phosphorus removal of locally adapted plant species used in constructed wetlands in China.

    PubMed

    Yu, Xia; König, Thomas; Qi, Zhang; Yongsheng, Gao

    2012-01-01

    This paper assesses the nitrogen and phosphorus removal efficiency of seven plant species (Schoenoplectus lacustris, Vetiveria zizanioides, Acorus calamus, Canna indica, Zizania latifolia, Phragmites communis, and Iris pseudacorus) commonly used in constructed wetland systems in southern China. The investigation considers two aspects that are relevant to determine nutrient removal efficiency: plants' biomass production and nutrient content in water effluent. Both assessments are correlated with each other. Three different hydraulic retention times with different nutrient loads have been applied in this ex-situ trial. The plants' biomass production correlates positively with the effluent's nutrient removal efficiency. Six out of seven species reviewed produce more biomass above ground than below ground (average: 67% of dried biomass in aerial part); only I. pseudacorus produces more biomass below ground. S. lacustris, V. zizanioides, I. pseudacorus, and C. indica have performed best in terms of nutrient removal efficiency (65.6-90.2% for nitrogen; 67.7-84.6% for phosphorus). PMID:22766855

  2. Immunity: plants as effective mediators.

    PubMed

    Sultan, M Tauseef; Butt, Masood Sadiq; Qayyum, Mir M Nasir; Suleria, Hafiz Ansar Rasul

    2014-01-01

    In the domain of nutrition, exploring the diet-health linkages is major area of research. The outcomes of such interventions led to widespread acceptance of functional and nutraceutical foods; however, augmenting immunity is a major concern of dietary regimens. Indeed, the immune system is incredible arrangement of specific organs and cells that enabled humans to carry out defense against undesired responses. Its proper functionality is essential to maintain the body homeostasis. Array of plants and their components hold immunomodulating properties. Their possible inclusion in diets could explore new therapeutic avenues to enhanced immunity against diseases. The review intended to highlight the importance of garlic (Allium sativum), green tea (Camellia sinensis), ginger (Zingiber officinale), purple coneflower (Echinacea), black cumin (Nigella sativa), licorice (Glycyrrhiza glabra), Astragalus and St. John's wort (Hypericum perforatum) as natural immune boosters. These plants are bestowed with functional ingredients that may provide protection against various menaces. Modes of their actions include boosting and functioning of immune system, activation and suppression of immune specialized cells, interfering in several pathways that eventually led to improvement in immune responses and defense system. In addition, some of these plants carry free radical scavenging and anti-inflammatory activities that are helpful against cancer insurgence. Nevertheless, interaction between drugs and herbs/botanicals should be well investigated before recommended for their safe use, and such information must be disseminated to the allied stakeholders.

  3. Performance evaluation of planted and unplanted subsurface-flow constructed wetlands for the post-treatment of UASB reactor effluents.

    PubMed

    Dornelas, Filipe Lima; Machado, Matheus Boechat; von Sperling, Marcos

    2009-01-01

    A system comprised by a UASB (Upflow Anaerobic Sludge Blanket) reactor followed by two horizontal subsurface-flow constructed wetlands in parallel was evaluated for the treatment of the wastewater generated in the city of Belo Horizonte, Brazil (50 inhabitants each unit). One unit was planted (Typha latifolia) and the other was unplanted. Influent and effluent samples were collected for a period of seven months. The systems were able to produce final effluents with low concentrations of organic matter and suspended solids, but showed not to be efficient in the removal of nutrients. Mean effluent concentrations for the planted and unplanted units were, respectively: BOD: 15 and 19 mg/L; COD: 42 and 64 mg/L; TSS: 3 and 5 mg/L; TN: 27 and 33 mg/L; N-NH(3): 25 and 29 mg/L; P Total: 1.2 and 1.5 mg/L. The planted wetland presented effluent concentrations and removal efficiencies significantly (Wilcoxon matched-pairs test, 5% significance level) better than the unplanted unit for most constituents. The study shows that horizontal subsurface-flow constructed wetlands can be effectively used as a post-treatment option for the effluent from UASB reactors.

  4. Changes in the bacterial community structure in two-stage constructed wetlands with different plants for industrial wastewater treatment.

    PubMed

    Calheiros, Cristina S C; Duque, Anouk F; Moura, Alexandra; Henriques, Isabel S; Correia, António; Rangel, António O S S; Castro, Paula M L

    2009-07-01

    This study focused on the diversity of bacterial communities from two series of two-stage constructed wetlands (CWs) treating tannery wastewater, under different hydraulic conditions. Series were separately planted with Typha latifolia and Phragmites australis in expanded clay aggregates and operated for 31 months. The effect of plant species, hydraulic loading and unit stage on bacterial communities was addressed through bacterial enumeration and denaturating gradient gel electrophoresis (DGGE). Diverse and distinct bacterial communities were found in each system unit, which was related in part to the type of plant and stage position (first or second unit in the series). Numerical analysis of DGGE profiles showed high diversity in each unit with an even distribution of species. No clear relation was established between the sample collection time, hydraulic loading applied and the bacterial diversity. Isolates retrieved from plant roots and substrates of CWs were affiliated with gamma-Proteobacteria, Firmicutes, alpha-Proteobacteria, Sphingobacteria, Actinobacteria and Bacteroidetes. Both series were effective in removing organic matter from the inlet wastewater, however, based on batch degradation experiments it seems that biodegradation was limited by the recalcitrant properties of the wastewater.

  5. The Effect of Structured Divergent Prompts on Knowledge Construction

    ERIC Educational Resources Information Center

    Howell, Ginger S.; Akpanudo, Usenime; Chen, Mengyi; Sutherlin, Autumn L.; James, Laura E.

    2014-01-01

    Discussion forums are a widely used activity in online courses. However, knowledge construction within online discussion rarely reaches higher levels. Therefore, it is important to understand which aspects of online discussion encourage learning and increase knowledge construction. This paper investigates the effect three Structured Divergent…

  6. Effects of invasive plants on arthropods.

    PubMed

    Litt, Andrea R; Cord, Erin E; Fulbright, Timothy E; Schuster, Greta L

    2014-12-01

    Non-native plants have invaded nearly all ecosystems and represent a major component of global ecological change. Plant invasions frequently change the composition and structure of vegetation communities, which can alter animal communities and ecosystem processes. We reviewed 87 articles published in the peer-reviewed literature to evaluate responses of arthropod communities and functional groups to non-native invasive plants. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Taxonomic richness decreased in 48% of studies and increased in 13%. Herbivorous arthropods decreased in response to plant invasions in 48% of studies and increased in 17%, likely due to direct effects of decreased plant diversity. Predaceous arthropods decreased in response to invasive plants in 44% of studies, which may reflect indirect effects due to reductions in prey. Twenty-two percent of studies documented increases in predators, which may reflect changes in vegetation structure that improved mobility, survival, or web-building for these species. Detritivores increased in 67% of studies, likely in response to increased litter and decaying vegetation; no studies documented decreased abundance in this functional group. Although many researchers have examined effects of plant invasions on arthropods, sizeable information gaps remain, specifically regarding how invasive plants influence habitat and dietary requirements. Beyond this, the ability to predict changes in arthropod populations and communities associated with plant invasions could be improved by adopting a more functional and mechanistic approach. Understanding responses of arthropods to invasive plants will critically inform conservation of virtually all biodiversity and ecological processes because so many organisms depend on arthropods as prey or for their functional roles, including pollination, seed dispersal, and decomposition. Given their short generation times and ability to respond rapidly to

  7. Effects of invasive plants on arthropods.

    PubMed

    Litt, Andrea R; Cord, Erin E; Fulbright, Timothy E; Schuster, Greta L

    2014-12-01

    Non-native plants have invaded nearly all ecosystems and represent a major component of global ecological change. Plant invasions frequently change the composition and structure of vegetation communities, which can alter animal communities and ecosystem processes. We reviewed 87 articles published in the peer-reviewed literature to evaluate responses of arthropod communities and functional groups to non-native invasive plants. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Taxonomic richness decreased in 48% of studies and increased in 13%. Herbivorous arthropods decreased in response to plant invasions in 48% of studies and increased in 17%, likely due to direct effects of decreased plant diversity. Predaceous arthropods decreased in response to invasive plants in 44% of studies, which may reflect indirect effects due to reductions in prey. Twenty-two percent of studies documented increases in predators, which may reflect changes in vegetation structure that improved mobility, survival, or web-building for these species. Detritivores increased in 67% of studies, likely in response to increased litter and decaying vegetation; no studies documented decreased abundance in this functional group. Although many researchers have examined effects of plant invasions on arthropods, sizeable information gaps remain, specifically regarding how invasive plants influence habitat and dietary requirements. Beyond this, the ability to predict changes in arthropod populations and communities associated with plant invasions could be improved by adopting a more functional and mechanistic approach. Understanding responses of arthropods to invasive plants will critically inform conservation of virtually all biodiversity and ecological processes because so many organisms depend on arthropods as prey or for their functional roles, including pollination, seed dispersal, and decomposition. Given their short generation times and ability to respond rapidly to

  8. Vegetation effects on anammox spatial distribution and nitrogen removal in constructed wetlands treated with domestic sewage.

    PubMed

    Wang, Ling; Li, Tian

    2014-01-01

    In this study, two horizontal subsurface-flow constructed wetlands (CWs) (planted and unplanted) were constructed and compared to investigate the effects of vegetation on nitrogen removal and anammox (anaerobic ammonium oxidation) spatial distribution and enrichment. Calamus (Acorus calamus L.), which has a large root system, was selected as the vegetation. Removal of total nitrogen from the planted wetland was much higher than that from the unplanted one. Radial oxygen loss from calamus provided the planted wetland with better oxygen restoration ability, benefitting ammonium removal in the CW, especially when anammox was inhibited under winter temperatures. Enrichment of anammox bacteria in planted wetlands was much greater than that in unplanted ones. The greatest enrichment of anammox bacteria occurred in the middle layer, which had a better anaerobic environment and moderate root system. The reduced rate of metabolism in plants during winter led to a sharp decrease in anammox bacteria copy numbers in the planted wetland. Under cold temperature, the degree of enrichment with anammox bacteria in the planted wetland was similar to or slightly superior to that in the unplanted wetland.

  9. Tomato transgenic plants expressing hairpin construct of a nematode protease gene conferred enhanced resistance to root-knot nematodes

    PubMed Central

    Dutta, Tushar K.; Papolu, Pradeep K.; Banakar, Prakash; Choudhary, Divya; Sirohi, Anil; Rao, Uma

    2015-01-01

    Root-knot nematodes (Meloidogyne incognita) cause substantial yield losses in vegetables worldwide, and are difficult to manage. Continuous withdrawal of environmentally-harmful nematicides from the global market warrants the need for novel nematode management strategies. Utility of host-delivered RNAi has been demonstrated in several plants (Arabidopsis, tobacco, and soybean) that exhibited resistance against root-knot and cyst nematodes. Herein, a M. incognita-specific protease gene, cathepsin L cysteine proteinase (Mi-cpl-1), was targeted to generate tomato transgenic lines to evaluate the genetically modified nematode resistance. In vitro knockdown of Mi-cpl-1 gene led to the reduced attraction and penetration of M. incognita in tomato, suggesting the involvement of Mi-cpl-1 in nematode parasitism. Transgenic expression of the RNAi construct of Mi-cpl-1 gene resulted in 60–80% reduction in infection and multiplication of M. incognita in tomato. Evidence for in vitro and in vivo silencing of Mi-cpl-1 was confirmed by expression analysis using quantitative PCR. Our study demonstrates that Mi-cpl-1 plays crucial role during plant-nematode interaction and plant-mediated downregulation of this gene elicits detrimental effect on M. incognita development, reinforcing the potential of RNAi technology for management of phytonematodes in crop plants. PMID:25883594

  10. Spatial effects favour the evolution of niche construction.

    PubMed

    Silver, Matt; Di Paolo, Ezequiel

    2006-12-01

    We present an individual-based, spatial implementation of an existing two-locus population genetic model of niche construction. Our analysis reveals that, across a broad range of conditions, niche-construction traits can drive themselves to fixation by simultaneously generating selection that favours 'recipient' trait alleles and linkage disequilibrium between niche-construction and recipient trait alleles. The effect of spatiality is key, since it is the local, resource-mediated interaction between recipient and niche-constructing loci which gives rise to gene linkage. Spatial clustering effects point to a possible mechanism by which an initially rare recipient trait whose selection depends on niche construction could establish in an otherwise hostile environment. The same mechanism could also lead to the spread of an established niche-constructing colony. Similar phenomena are observed in the spatial modelling of two species 'engineering webs'. Here, the activities of two niche-constructing species can combine to drive a particular recipient trait to fixation, or in certain circumstances, maintain the presence of polymorphisms through the preservation of otherwise deleterious alleles. This may have some relevance to ecosystem stability and the maintenance of genetic variation, where the frequencies of key resources are affected by the niche-constructing activities of more than one species. Our model suggests that the stability of multi-species webs in natural populations may increase as the complexity of species-environment interactions increases.

  11. A Post Licensing Study of Community Effects at Two Operating Nuclear Power Plants. Final Report.

    ERIC Educational Resources Information Center

    Purdy, Bruce J.; And Others

    In an effort to identify and assess the social, economic, and political effects of nuclear power plant construction and operation upon two host communities (Plymouth, Massachusetts and Waterford, Connecticut), a post-licensing review revealed that the primary impact of the nuclear power plants in both communities was an increase in the property…

  12. A Plutonium Finishing Plant Model for the Cercla Removal Action and Decommissioning Construction Final Report

    SciTech Connect

    Hopkins, A.

    2008-07-01

    The joint policy between the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE) for decommissioning buildings at DOE facilities documents an agreement between the agencies to perform decommissioning activities including demolition under the Comprehensive Environmental Response Compensation and Liability Act (CERCLA). The use of removal actions for decommissioning integrates EPA oversight authority, DOE lead agency responsibility, and state authority for decommissioning activities. Once removal actions have been performed under CERCLA, a construction completion report is required to document the completion of the required action. Additionally, a decommissioning report is required under DOE guidance. No direct guidance was found for documenting completion of decommissioning activities and preparing a final report that satisfies the CERCLA requirements and the DOE requirements for decommissioning. Additional guidance was needed for the documentation of construction completion under CERCLA for D and D projects undertaken under the joint policy that addresses the requirements of both agencies. A model for the construction completion report was developed to document construction completion for CERCLA D and D activities performed under the joint EPA/DOE policy at the Plutonium Finishing Plant (PFP). The model documentation report developed at PFP integrates the DOE requirements for establishing decommissioning end-points, documenting end-point completion and preparing a final decommissioning report with the CERCLA requirements to document completion of the action identified in the Action Memorandum (AM). The model includes the required information on health and safety, data management, cost and schedule and end-points completion. (authors)

  13. Purification of fuel and nitrate contaminated ground water using a free water surface constructed wetland plant

    SciTech Connect

    Machate, T.; Heuermann, E.; Schramm, K.W.; Kettrup, A.

    1999-10-01

    Contaminated ground water from a former coke plant site was purified in a free water surface (FWS) constructed wetland plant during a 3-mo short-term experiment. The pilot plant (total surface area 27 m{sup 2}) was filled with a 1 m thick lava-gravel substrate planted with cattail (Typha spp.) and bulrush (Scirpus lacustrls). Major contaminants were low to moderate concentrations of polycyclic aromatic hydrocarbons, BTEX, nitrate, and nitrite. The wetland was dosed at hydraulic loading rates of q{sub A} = 4.8 and 9.6 cm d{sup {minus}1} with a hydraulic residence time (HRT) of 13.7 and 6.8 d. The surface removal rates of PAH were between 98.8 and 1914 mg m{sup {minus}2} d{sup {minus}1}. Efficiency was always {gt}99%. Extraction of lava gravel showed that approx. 0.4% of the applied PAH were retained on the substratum. The ratio of {Sigma}2,3-ring PAH and {Sigma}4,5,6-ring PAH showed a shift from 1:0.11 in water to 1:2.5 in lava. The removal of BTEX was {gt}99%, but might be in part due to volatilization. The efficiency in the removal of nitrate was 91% and of nitrite was 97%. Purification performance was not influenced by hydraulic loading rates or after die-back of the macrophytes.

  14. Microbial abundance and community in subsurface flow constructed wetland microcosms: role of plant presence.

    PubMed

    Wang, Qian; Xie, Huijun; Ngo, Huu Hao; Guo, Wenshan; Zhang, Jian; Liu, Cui; Liang, Shuang; Hu, Zhen; Yang, Zhongchen; Zhao, Congcong

    2016-03-01

    In this research, the role of plants in improving microorganism growth conditions in subsurface flow constructed wetland (CW) microcosms was determined. In particular, microbial abundance and community were investigated during summer and winter in Phragmites australis-planted CW microcosms (PA) and unplanted CW microcosms (control, CT). Results revealed that the removal efficiencies of pollutants and microbial community structure varied in winter with variable microbial abundance. During summer, PA comprised more dominant phyla (e.g., Proteobacteria, Actinobacteria, and Bacteroidetes), whereas CT contained more Cyanobacteria and photosynthetic bacteria. During winter, the abundance of Proteobacteria was >40 % in PA but dramatically decreased in CT. Moreover, Cyanobacteria and photosynthetic bacterial dominance in CT decreased. In both seasons, bacteria were more abundant in root surfaces than in sand. Plant presence positively affected microbial abundance and community. The potential removal ability of CT, in which Cyanobacteria and photosynthetic bacteria were abundant during summer, was more significantly affected by temperature reduction than that of PA with plant presence. PMID:25772872

  15. Processes and Effects in the Construction of Social Reality: Construct Accessibility as an Explanatory Variable.

    ERIC Educational Resources Information Center

    Shrum, L. J.; O'Guinn, Thomas C.

    1993-01-01

    Finds support for the general notion of construct accessibility and its effect on judgments can help account for the influence of television viewing on social reality estimates. Shows that subjects who watch comparatively more television not only overestimate frequency or probability but also give faster responses to various types of cultivation…

  16. Construction of effective inverted repeat silencing constructs using sodium bisulfite treatment coupled with strand-specific PCR.

    PubMed

    Taylor, Sarah H; Harmse, Johan; Arbuthnot, Patrick; Van Den Berg, Fiona; Weinberg, Marco S; Rey, Marie E C

    2012-04-01

    RNA silencing has been exploited to produce transgenic plants with resistance to viral pathogens via posttranscriptional gene silencing (PTGS). In some cases, this technology is difficult to apply due to the instability of inverted repeat (IR) constructs during cloning and plant transformation. Although such constructs have been shown to be stabilized with introns and efficiently induce RNA silencing, we found that the Pdk intron did not stabilize South African cassava mosaic virus (SACMV) silencing constructs. Therefore, we developed a method for producing long SACMV IR constructs through bisulfite-induced base pair mismatches on the sense arm prior to IR assembly. Expression of SACMV BC1 mismatched IR constructs in the model test plant Nicotiana benthamiana resulted in a reduction in viral BC1 transcript levels, hence viral replication, upon SACMV infection. Mismatched SACMV AC1 IR constructs induced PTGS more efficiently in a N. benthamiana callus system than nonmismatched IR constructs. Our novel method for IR construct generation should be applicable to many sequences where the generation of these constructs has proven difficult in the past.

  17. Construction of effective inverted repeat silencing constructs using sodium bisulfite treatment coupled with strand-specific PCR.

    PubMed

    Taylor, Sarah H; Harmse, Johan; Arbuthnot, Patrick; Van Den Berg, Fiona; Weinberg, Marco S; Rey, Marie E C

    2012-04-01

    RNA silencing has been exploited to produce transgenic plants with resistance to viral pathogens via posttranscriptional gene silencing (PTGS). In some cases, this technology is difficult to apply due to the instability of inverted repeat (IR) constructs during cloning and plant transformation. Although such constructs have been shown to be stabilized with introns and efficiently induce RNA silencing, we found that the Pdk intron did not stabilize South African cassava mosaic virus (SACMV) silencing constructs. Therefore, we developed a method for producing long SACMV IR constructs through bisulfite-induced base pair mismatches on the sense arm prior to IR assembly. Expression of SACMV BC1 mismatched IR constructs in the model test plant Nicotiana benthamiana resulted in a reduction in viral BC1 transcript levels, hence viral replication, upon SACMV infection. Mismatched SACMV AC1 IR constructs induced PTGS more efficiently in a N. benthamiana callus system than nonmismatched IR constructs. Our novel method for IR construct generation should be applicable to many sequences where the generation of these constructs has proven difficult in the past. PMID:22482441

  18. Effects of static magnetic fields on plants.

    NASA Astrophysics Data System (ADS)

    Kuznetsov, O.

    In our recent experiment on STS-107 (MFA-Biotube) we took advantage of the magnetic heterogeneity of the gravity receptor cells of flax roots, namely stronger diamagnetism of starch-filled amyloplasts compared to cytoplasm (Δ ≊ < 0). High gradient magnetic fields (HGMF, grad(H2/2) up to 109-1010 Oe2/cm) of the experimental chambers (MFCs) repelled amyloplasts from the zones of stronger field thus providing a directional stimulus for plant gravisensing system in microgravity, and causing the roots to react. Such reaction was observed in the video downlink pictures. Unfortunately, the ``Columbia'' tragedy caused loss of the plant material and most of the images, thus preventing us from detailed studies of the results. Currently we are looking for a possibility to repeat this experiment. Therefore, it is very important to understand, what other effects (besides displacing amyloplasts) static magnetic fields with intensities 0 to 2.5104 Oe, and with the size of the area of non-uniformity 10-3 to 1 cm. These effects were estimated theoretically and tested experimentally. No statistically significant differences in growth rates or rates of gravicurvature were observed in experiments with Linum, Arabidopsis, Hordeum, Avena, Ceratodon and Chara between the plants grown in uniform magnetic fields of various intensities (102 to 2.5104 Oe) and those grown in the Earth's magnetic field. Microscopic studies also did not detect any structural differences between test and control plants. The magnitudes of possible effects of static magnetic fields on plant cells and organs (including effects on ion currents, magneto-hydrodynamic effects in moving cytoplasm, ponderomotive forces on other cellular structures, effects on some biochemical reactions and biomolecules) were estimated theoretically. The estimations have shown, that these effects are small compared to the thermodynamic noise and thus are insignificant. Both theoretical estimations and control experiments confirm, that

  19. Effective Stimuli for Constructing Reliable Neuron Models

    PubMed Central

    Druckmann, Shaul; Berger, Thomas K.; Schürmann, Felix; Hill, Sean; Markram, Henry; Segev, Idan

    2011-01-01

    The rich dynamical nature of neurons poses major conceptual and technical challenges for unraveling their nonlinear membrane properties. Traditionally, various current waveforms have been injected at the soma to probe neuron dynamics, but the rationale for selecting specific stimuli has never been rigorously justified. The present experimental and theoretical study proposes a novel framework, inspired by learning theory, for objectively selecting the stimuli that best unravel the neuron's dynamics. The efficacy of stimuli is assessed in terms of their ability to constrain the parameter space of biophysically detailed conductance-based models that faithfully replicate the neuron's dynamics as attested by their ability to generalize well to the neuron's response to novel experimental stimuli. We used this framework to evaluate a variety of stimuli in different types of cortical neurons, ages and animals. Despite their simplicity, a set of stimuli consisting of step and ramp current pulses outperforms synaptic-like noisy stimuli in revealing the dynamics of these neurons. The general framework that we propose paves a new way for defining, evaluating and standardizing effective electrical probing of neurons and will thus lay the foundation for a much deeper understanding of the electrical nature of these highly sophisticated and non-linear devices and of the neuronal networks that they compose. PMID:21876663

  20. Effect of feeding strategies on pharmaceutical removal by subsurface flow constructed wetlands.

    PubMed

    Zhang, Dong Qing; Gersberg, Richard M; Hua, Tao; Zhu, Junfei; Nguyen, Anh Tuan; Law, Wing-Keung; Ng, Wun Jern; Tan, Soon Keat

    2012-01-01

    This study presents findings on an assessment of the effect of continuous and batch feeding strategies on the removal of selected pharmaceuticals from synthetic wastewater. Six mesocosm-scale constructed wetlands, including three horizontal subsurface flow constructed wetlands and three sand filters, were set up at the campus of Nanyang Technological University, Singapore. The findings showed that ibuprofen and diclofenac removal in the wetlands was significantly ( < 0.05) enhanced in the batch versus continuous mode. In contrast, naproxen and carbamazepine showed no significant differences ( > 0.05) in elimination under either feeding strategy. Our results also clearly showed that the presence of plants exerts a stimulatory effect on pharmaceutical removal for ibuprofen, diclofenac, and naproxen in batch and continuous mode. Estimation of the quantitative role of this stimulatory effect on pharmaceutical elimination of batch operation as compared with the effect of the presence of the higher plant alone showed that batch operation may account for 40 to 87% of the contribution conferred by the aquatic plant. The findings of this study imply that where maximal removal of pharmaceutical compounds is desired, periodic draining and filling might be the preferred operational strategy for full-scale, subsurface flow constructed wetlands.

  1. H-Coal Pilot Plant Phase II construction, Catlettsburg, Kentucky. Final construction management report, December 1976-February 1980. [February, 1977 to approximately January, 1980

    SciTech Connect

    Not Available

    1983-03-01

    This report covers the H-Coal Pilot Plant facility located in Catlettsburg, Kentucky. The authorization for this project was under DOE contract No. DE-AC05-78ET11052, formally ET-78-C-01-3224. Badger Plants, Inc. carried out the construction management of this facility. The estimated total cost is $147,265,013. A brief process/technical description of the Pilot Plant covers subjects such as objectives, capacity, expected life, etc. A brief technical description of each processing unit, including its purpose in the overall operations of the plant is given. A general description of the organizational history of the project is given. Current overall organization and a description of the responsibilities of each participant are included. Badger Plant's organization at manager level is shown.

  2. Effect of cadmium on symbiotic soybean plants

    SciTech Connect

    Borges, A.C.; Wollum, A.G. II

    1981-04-01

    The potential for environmental contamination by cadmium (Cd) has increased significantly in recent years. Since Cd may be hazardous to living systems, a study was conducted to investigate: (1) the existence of Rhizobium japonicum strains tolerant to Cd, (2) the Cd effect on the symbiosis between host soybean plants (Glycine max (L.) Merr.) and R. japonicum strains with different Cd tolerances, and (3) interactions and distribution of Cd and other elements in the host when biomass is decreased by Cd. The existence of R. japonicum strains tolerant to Cd was assessed by comparing growth curves of 10 different strains growing in a basal medium with gluconate, yeast extract, L-arabinose, and Cd (0, 3.5, 7, 14, and 28 ..mu..g/ml). Strain 3Ilb110 (110) exhibited a tolerance to Cd after an initial lag in growth, while strain 3Ilb123 (123) was susceptible. Strains 110 and 123 were used to inoculate plants growing in nutrient solution with Perlite as a support medium to evaluate the plant-rhizobial interactions in the presence of 0, 2.2, 6.7, 10.1, and 20.2 ..mu..g Cd/ml, respectively. Plants were harvested and tops, roots, and nodules were analyzed 23 days after starting Cd application. Cadmium decreased dry matter production of tops, roots, and nodules. Plants inoculated with strain 123 accumulated significantly more dry matter in nodules than those with strain 110. However, in the presence of 0 and 2.2 ..mu..g Cd/ml, plants innoculated with strain 110 accumulated significantly more N than plants innoculated with strain 123. Nutrient imbalances were observed in the presence of Cd. It is suggested that the interactions of Cd with some nutrients may contribute to Cd toxicity in soybean plants. In this study the most pronounced Cd effect was on Fe and Mn nutrition, rather than Zn as had been previously reported.

  3. Constructing more informative plant-pollinator networks: visitation and pollen deposition networks in a heathland plant community.

    PubMed

    Ballantyne, G; Baldock, Katherine C R; Willmer, P G

    2015-09-01

    Interaction networks are widely used as tools to understand plant-pollinator communities, and to examine potential threats to plant diversity and food security if the ecosystem service provided by pollinating animals declines. However, most networks to date are based on recording visits to flowers, rather than recording clearly defined effective pollination events. Here we provide the first networks that explicitly incorporate measures of pollinator effectiveness (PE) from pollen deposition on stigmas per visit, and pollinator importance (PI) as the product of PE and visit frequency. These more informative networks, here produced for a low diversity heathland habitat, reveal that plant-pollinator interactions are more specialized than shown in most previous studies. At the studied site, the specialization index [Formula: see text] was lower for the visitation network than the PE network, which was in turn lower than [Formula: see text] for the PI network. Our study shows that collecting PE data is feasible for community-level studies in low diversity communities and that including information about PE can change the structure of interaction networks. This could have important consequences for our understanding of threats to pollination systems. PMID:26336181

  4. Bacterial community variation and microbial mechanism of triclosan (TCS) removal by constructed wetlands with different types of plants.

    PubMed

    Zhao, Congcong; Xie, HuiJun; Xu, Jingtao; Xu, Xiaoli; Zhang, Jian; Hu, Zhen; Liu, Cui; Liang, Shuang; Wang, Qian; Wang, Jingmin

    2015-02-01

    Triclosan (TCS) is a broad-spectrum synthetic antimicrobial agent that is toxic to microbes and other aquatic organisms. Constructed wetlands (CWs) are now popular in TCS removal. However, knowledge on the effects of TCS on the bacterial community and microbial removal mechanism in CWs is lacking. The effects of TCS (60 μg L(-1)) on bacterial communities in batch-loaded CWs with emergent (Typha angustifolia), submerged (Hydrilla verticillata), and floating plant (Salvinia natans) were analyzed by 454 pyrosequencing technology. After six periods of experiment, the TCS removal efficiencies were over 90% in CWs, and negative effects of TCS on bacterial community richness and diversity were observed. Moreover, plant species effect existed. Bacterial strains that contributed to TCS biodegradation in CWs were successfully identified. In TCS-treated T. angustifolia and H. verticillata CWs, beta-Proteobacteria increased by 16.63% and 18.20%, respectively. In TCS-treated S. natans CWs, delta- and gamma-Proteobacteria and Sphingobacteria increased by 9.36%, 19.49%, and 31.37%, respectively, and could relate to TCS biodegradation. TCS affected the development of certain bacteria, and eventually, the bacterial community structures in CWs. This research provided ecologically relevant information on bacterial community and microbial removal mechanism in CWs under TCS treatment.

  5. Deriving a Planting Medium from Solid Waste Compost and Construction, Demolition and Excavation Waste

    NASA Astrophysics Data System (ADS)

    Farajalla, Nadim; Assaf, Eleni; Bashour, Issam; Talhouk, Salma

    2014-05-01

    Lebanon's very high population density has been increasing since the end of the war in the early 1990s reaching 416.36 people per square kilometer. Furthermore, the influx of refugees from conflicts in the region has increased the resident population significantly. All these are exerting pressure on the country's natural resources, pushing the Lebanese to convert more forest and agricultural land into roads, buildings and houses. This has led to a building boom and rapid urbanization which in turn has created a demand for construction material - mainly rock, gravel, sand, etc. nearly all of which were locally acquired through quarrying to the tune of three million cubic meters annually. This boom has been followed by a war with Israel in 2006 which resulted in thousands of tonnes of debris. The increase in population has also led to an increase in solid waste generation with 1.57 million tonnes of solid waste generated in Lebanon per year. The combination of construction, demolition and excavation (CDE) waste along with the increase in solid waste generation has put a major stress on the country and on the management of its solid waste problem. Compounding this problem are the issues of quarries closure and rehabilitation and a decrease in forest and vegetative cover. The on-going research reported in this paper aims to provide an integrated solution to the stated problem by developing a "soil mix" derived from a mélange of the organic matter of the solid waste (compost), the CDE waste, and soil. In this mix, native and indicator plants are planted (in pots) from which the most productive mix will be selected for further testing at field level in later experiments. The plant species used are Matiolla, a native Lebanese plant and Zea mays, which is commonly known used as an indicator plant due to its sensitivity to environmental conditions. To ensure sustainability and environmental friendliness of the mix, its physical and chemical characteristics are monitored

  6. Microgravity Effects on Plant Growth and Lignification

    NASA Astrophysics Data System (ADS)

    Cowles, Joe R.; Lemay, Richard; Jahns, Gary

    1988-12-01

    Lignin is a major cellular component of higher plants. One function of lignin is to support vertical plant growth in a gravity environment. Various investigators working in the 1 g environment have concluded that lignification is influenced by gravity. An experiment was designed for flight on Spacelab II to determine the effect of microgravity on lignification in young plant seedlings. A secondary objective of the experiment was to examine the effect of microgravity on overall seedling growth. Mung bean and oat seeds germinated and the seedlings grew during the Spacelab II mission. Growth of flight mung bean and oat seedlings, however, was slower, and the seedlings exhibited stem and root orientation difficulties. Flight pine seedlings were similar in appearance and growth to 1 g controls. The rate of lignin formation in seedlings grown in space was significantly less in all three species in comparison to 1 g controls. The experiment provided direct evidence that lignification is slowed in a microgravity environment.

  7. Worldwide construction

    SciTech Connect

    Williamson, M.

    1994-10-17

    The paper lists major construction projects in worldwide processing and pipelining, showing capacities, contractors, estimated costs, and time of construction. The lists are divided into refineries, petrochemical plants, sulfur recovery units, gas processing plants, pipelines, and related fuel facilities. This last classification includes cogeneration plants, coal liquefaction and gasification plants, biomass power plants, geothermal power plants, integrated coal gasification combined-cycle power plants, and a coal briquetting plant.

  8. The greenhouse effect: Physiological changes in plants

    SciTech Connect

    Beard, R.; Harrison, M. )

    1990-05-01

    Elevated atmospheric carbon dioxide is timely topic of study for all biology students at all levels. The stimulatory effect of elevated atmospheric carbon dioxide (700 {mu}l/l) on plant growth, flower induction, protein production and the Calvin-Benson cycle can be easily demonstrated in seedlings in student laboratories. In our lab, the shoot growth of rapid cycling brassicas (Wisconsin fast plants) was measured under ambient and elevated CO{sub 2} conditions for three weeks. Plants grown under elevated CO{sub 2} conditions were significantly taller and showed earlier flower development. These plants also contained greater protein content per gram fresh weight. Crude leaf extracts was used as a source of pentose-5-isomerase which controls the conversion of ribose-5-phosphate to ribulose-5-phosphate in carbon fixation. The activity of this enzyme was measured spectrophotometrically and found to be somewhat greater in plants grown under the higher CO{sub 2} conditions. These physiological changes associated with elevated CO{sub 2} can be used as an introduction to the greenhouse effect as well as to study the regulation of carbon fixation.

  9. Improving low-temperature performance of surface flow constructed wetlands using Potamogeton crispus L. plant.

    PubMed

    Fan, Jinlin; Zhang, Jian; Ngo, Huu Hao; Guo, Wenshan; Yin, Xiaole

    2016-10-01

    In this study, enhanced organics and nitrogen removal efficiency in SFCWs by different submerged plants for polluted river water treatment under cold temperature was evaluated. High average removal efficiencies of COD (92.45%), NH4(+)-N (93.70%) and TN (55.62%) were achieved in experimental SFCWs with Potamogeton crispus compared with SFCWs with other plants. SFCWs with underground Phragmites australis root also presented better performance than the unplanted systems, indicating its positive role of contamination removal in winter. The results of this study indicated SFCWs with hardy submerged plant P. crispus could be a more effective and sustainable strategy for removing organics and nitrogen in shallow nutrient enriched river water ecosystems under cold climate. PMID:27381001

  10. Improving low-temperature performance of surface flow constructed wetlands using Potamogeton crispus L. plant.

    PubMed

    Fan, Jinlin; Zhang, Jian; Ngo, Huu Hao; Guo, Wenshan; Yin, Xiaole

    2016-10-01

    In this study, enhanced organics and nitrogen removal efficiency in SFCWs by different submerged plants for polluted river water treatment under cold temperature was evaluated. High average removal efficiencies of COD (92.45%), NH4(+)-N (93.70%) and TN (55.62%) were achieved in experimental SFCWs with Potamogeton crispus compared with SFCWs with other plants. SFCWs with underground Phragmites australis root also presented better performance than the unplanted systems, indicating its positive role of contamination removal in winter. The results of this study indicated SFCWs with hardy submerged plant P. crispus could be a more effective and sustainable strategy for removing organics and nitrogen in shallow nutrient enriched river water ecosystems under cold climate.

  11. [Development characteristics of aquatic plants in a constructed wetland for treating urban drinking water source at its initial operation stage].

    PubMed

    Zheng, Jun; Ma, Xin-Tang; Zhou, Lan; Zhou, Qing-Yuan; Wang, Zhong-Qiong; Wang, Wei-Dong; Yin, Cheng-Qing

    2011-08-01

    The development characteristics and improvement measures of aquatic plants were studied in Shijiuyang Constructed Wetland (SCW) at its initial operation stage. SCW was a large-scale wetland aiming to help relieve the source water pollution in Jiaxing City. A checklist of vascular plants in SCW was built, and species composition, life forms, biomass and association distributions were examined. Our objectives were to examine the diversity and community structure of aquatic plants in SCW at its initial operation stage, and to find out the possible hydrophyte improvement measures. The survey results showed that there were 49 vascular plant species belonging to 41 genera, 25 families in SCW, which greatly exceeded the artificially transplanted 13 species. The life forms of present aquatic plants in SCW were dominated by hygrophilous plants (20 species) and emerged plants (17 species), which accounted for 75.5% of the total number of aquatic plants. The aquatic plants transplanted artificially were dominated by emerged plants (accounted for 69.2%), while those naturally developed were predominated by hygrophilous plants (accounted for 47.2%). The horizontal distribution of aquatic plant community in SCW was mixed in the form of mosaics, which made up typical association complex. Except association Aeschynomene indica L., the dominant species of other associations were all those transplanted artificially. The naturally grown species scattered throughout the SCW and only occupied a small percentage. A marked difference was detected on the species and species richness of aquatic plants in different regions of SCW. Biomass of aquatic plant associations in SCW was 167.7 t. SCW has shown a trend of succession heading for quick increase of plant diversity at the primary operation stage. This trend provides a good material base for the future stable community of aquatic plants in SCW. According to the current status of aquatic plants, some suggestions were put forward on the

  12. Bioremediation of endosulfan in laboratory-scale constructed wetlands: effect of bioaugmentation and biostimulation.

    PubMed

    Zhao, Congcong; Xie, HuiJun; Mu, Yang; Xu, Xiaoli; Zhang, Jian; Liu, Cui; Liang, Shuang; Ngo, Huu Hao; Guo, Wenshan; Xu, Jingtao; Wang, Qian

    2014-11-01

    Bioremediation is widely used in organic pollutants disposal. However, very little has been known on its application in constructed wetlands contaminated with organochlorine pesticide, endosulfan in particular. To evaluate the effect of bioremediation on endosulfan removal and clarify the fate, bioaugmentation and biostimulation were studied in laboratory-scale vertical-flow constructed wetlands. After 20 days' experiment, endosulfan isomers removal efficiencies were increased to 89.24-97.62 % through bioremediation. In bacteria bioaugmentation (E-in) and sucrose biostimulation (E-C), peak concentrations of endosulfan in sediment were reduced by 31.02-76.77 %, and plant absorption were 347.45-576.65 μg kg(-1). By contrast, plant absorption in KH2PO4 biostimulation (E-P) was increased to 811.64 and 1,067.68 μg kg(-1). Degradation process was probably promoted in E-in and E-C, while plant absorption was enhanced in E-P. Consequently, E-in and E-C were effective for endosulfan removal in constructed wetlands, while adding KH2PO4 had potential to cause air pollution. Additionally, combined bioremediation was not recommended. PMID:24969425

  13. 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

  14. The Communicative Effectiveness Survey: Preliminary Evidence of Construct Validity

    ERIC Educational Resources Information Center

    Donovan, Neila J.; Kendall, Diane L.; Young, Mary Ellen; Rosenbek, John C.

    2008-01-01

    Purpose: To provide preliminary evidence of the construct validity of the Communicative Effectiveness Survey (CES) for individuals with dysarthria and idiopathic Parkinson's disease (PD). Method: In a prospective, quasi-experimental design, 25 participants each were assigned to 3 groups (N = 75): PD and dysarthria, non-PD and no dysarthria, and PD…

  15. The Effect of Gender on the Construction of Backward Inferences

    ERIC Educational Resources Information Center

    Cakir, Ozler

    2008-01-01

    The main objective in the present study is to examine the effect of gender on primary school students' construction of elaborative backward inferences during text processing. A total of 333 children, aged 10-11 years (n = 158 girls and 175 boys) participated in the study. Each participant completed a backward inference test. The results indicate…

  16. Effectiveness of Push and Pull Learning Strategies in Construction Management.

    ERIC Educational Resources Information Center

    Santos, Aguinaldo; Powell, James Alfred

    2001-01-01

    Study of a construction contractor modernizing production showed that creation of an effective learning mood was more likely in a supportive environment in which people explore their actions as they work ("pull learning"). However, an external change agent ("push learning") was useful in provoking the reflection that triggered workplace learning.…

  17. Semantics of the Transitive Construction: Prototype Effects and Developmental Comparisons

    ERIC Educational Resources Information Center

    Ibbotson, Paul; Theakston, Anna L.; Lieven, Elena V. M.; Tomasello, Michael

    2012-01-01

    This paper investigates whether an abstract linguistic construction shows the kind of prototype effects characteristic of non-linguistic categories, in both adults and young children. Adapting the prototype-plus-distortion methodology of Franks and Bransford (1971), we found that whereas adults were lured toward false-positive recognition of…

  18. Comparison of carbon balance in Mediterranean pilot constructed wetlands vegetated with different C4 plant species.

    PubMed

    Barbera, Antonio C; Borin, Maurizio; Cirelli, Giuseppe L; Toscano, Attilio; Maucieri, Carmelo

    2015-02-01

    This study investigates carbon dioxide (CO2) and methane (CH4) emissions and carbon (C) budgets in a horizontal subsurface flow pilot-plant constructed wetland (CW) with beds vegetated with Cyperus papyrus L., Chrysopogon zizanioides (L.) Roberty, and Mischantus × giganteus Greef et Deu in the Mediterranean basin (Sicily) during the 1st year of plant growing season. At the end of the vegetative season, M. giganteus showed the higher biomass accumulation (7.4 kg m(-2)) followed by C. zizanioides (5.3 kg m(-2)) and C. papyrus (1.8 kg m(-2)). Significantly higher emissions of CO2 were detected in the summer, while CH4 emissions were maximum during spring. Cumulative CO2 emissions by C. papyrus and C. zizanioides during the monitoring period showed similar trends with final values of about 775 and 1,074 g m(-2), respectively, whereas M. giganteus emitted 3,395 g m(-2). Cumulative CH4 bed emission showed different trends for the three C4 plant species in which total gas release during the study period was for C. papyrus 12.0 g m(-2) and ten times higher for M. giganteus, while C. zizanioides bed showed the greatest CH4 cumulative emission with 240.3 g m(-2). The wastewater organic carbon abatement determined different C flux in the atmosphere. Gas fluxes were influenced both by plant species and monitored months with an average C-emitted-to-C-removed ratio for C. zizanioides, C. papyrus, and M. giganteus of 0.3, 0.5, and 0.9, respectively. The growing season C balances were positive for all vegetated beds with the highest C sequestered in the bed with M. giganteus (4.26 kg m(-2)) followed by C. zizanioides (3.78 kg m(-2)) and C. papyrus (1.89 kg m(-2)). To our knowledge, this is the first paper that presents preliminary results on CO2 and CH4 emissions from CWs vegetated with C4 plant species in Mediterranean basin during vegetative growth. PMID:24743957

  19. An Endophyte Constructs Fungicide-Containing Extracellular Barriers for Its Host Plant.

    PubMed

    Soliman, Sameh S M; Greenwood, John S; Bombarely, Aureliano; Mueller, Lukas A; Tsao, Rong; Mosser, Dick D; Raizada, Manish N

    2015-10-01

    Surface cracks create sites for pathogen invasion. Yew trees (Taxus) hyperbranch from long-lived buds that lie underneath the bark [1], resulting in persistent bark cracking and deep air pockets, potentially allowing pathogens to enter the nutrient-rich vascular system (vertical phloem and inter-connected radial medullary rays [MR]). Yew is famous as the source of the anti-cancer diterpenoid drug Taxol. A mystery has been why both the tree and its resident non-pathogenic fungi (endophytes) synthesize Taxol, apparently redundantly [2-7]. These endophytes, as well as pure Taxol, suppress fungal pathogens including wood-decaying fungi (WDF) [8-11]. Here we show that a Taxol-producing fungal endophyte, Paraconiothyrium SSM001 [12], migrates to pathogen entry points including branch cracks. The fungus sequesters Taxol in intracellular hydrophobic bodies that are induced by WDF for release by exocytosis, after which the bodies can coalesce to form remarkable extracellular barriers, laced with the fungicide. We propose that microbial construction of fungicide-releasing hydrophobic barriers might be a novel plant defense mechanism. We further propose that the endophyte might be evolutionarily analogous to animal immune cells, in that it might expand plant immunity by acting as an autonomous, anti-pathogen sentinel that monitors the vascular system. PMID:26412131

  20. Winter study of power plant effects

    SciTech Connect

    Patrinos, A.A.N.

    1980-10-01

    As a part of DOE's Meteorological Effects of Thermal Energy Releases (METER) program a field study was undertaken at the Bowen Electric Generating Plant (Plant Bowen) in December 1979. The study was a joint endeavor of Battelle Pacific Northwest Laboratories (PNL), Pennsylvania State University (PSU), and Oak Ridge National Laboratory (ORNL) with the main objective of determining the effects of the plant's smokestack effluents on aerosol characteristics and precipitation chemistry. Other objectives included studies of cooling tower temperature and humidity (T/h) plumes and drift drop concentrations. Conducted over a period of three weeks, the study involved an instrumented aircraft, pilot balloons, a tethered balloon system, a dense network of wetfall chemistry collectors and numerous ground- and tower-based meteorological instruments. Rainfall samples collected during the precipitation event of December 13, 1979, revealed some evidence of plume washout. The tethered balloon flights rarely detected the faint presence of the T/h plumes while the airborne measurements program concentrated on the study of SO/sub 2/ to sulfate conversion. A series of plume observations confirmed the suitability of the plant's windset for plume direction determinations.

  1. Evaluation of two gene-silencing constructs for resistance to tomato yellow leaf curl viruses in Nicotiana benthamiana plants.

    PubMed

    Gharsallah Chouchane, S; Gorsane, F; Nakhla, M K; Salus, M; Martin, C T; Maxwell, D P; Marrakchi, M; Fakhfakh, H

    2008-01-01

    Infiltration of Agrobacterium tumefaciens into intact plant leaves of N. benthamiana was used to test the efficiency of two virus-based silencing constructs conferring resistance to the closely related begomoviruses. The constructs contained the most conserved sequences of the coat protein (CP) gene and replication-associated protein (Rep) gene of Tomato yellow leaf curl Sardinia virus (Sicily strain) (TYLCSV-[Sic]). Both constructs formed a hairpin structure that enhanced the post-transcriptional gene-silencing mechanism. When agro-infiltrated plants were challenged separately with infectious viruses TYLCSV-[Sic] and Tomato yellow leaf curl virus (TYLCV), the plants showed resistance to TYLCSV-[Sic], but not to the related TYLCV. PMID:18999888

  2. Pervasive and strong effects of plants on soil chemistry: a meta-analysis of individual plant 'Zinke' effects.

    PubMed

    Waring, Bonnie G; Álvarez-Cansino, Leonor; Barry, Kathryn E; Becklund, Kristen K; Dale, Sarah; Gei, Maria G; Keller, Adrienne B; Lopez, Omar R; Markesteijn, Lars; Mangan, Scott; Riggs, Charlotte E; Rodríguez-Ronderos, María Elizabeth; Segnitz, R Max; Schnitzer, Stefan A; Powers, Jennifer S

    2015-08-01

    Plant species leave a chemical signature in the soils below them, generating fine-scale spatial variation that drives ecological processes. Since the publication of a seminal paper on plant-mediated soil heterogeneity by Paul Zinke in 1962, a robust literature has developed examining effects of individual plants on their local environments (individual plant effects). Here, we synthesize this work using meta-analysis to show that plant effects are strong and pervasive across ecosystems on six continents. Overall, soil properties beneath individual plants differ from those of neighbours by an average of 41%. Although the magnitudes of individual plant effects exhibit weak relationships with climate and latitude, they are significantly stronger in deserts and tundra than forests, and weaker in intensively managed ecosystems. The ubiquitous effects of plant individuals and species on local soil properties imply that individual plant effects have a role in plant-soil feedbacks, linking individual plants with biogeochemical processes at the ecosystem scale.

  3. Ecological effects of pipeline construction through deciduous forested wetlands, Midland County, Michigan

    SciTech Connect

    Zellmer, S.D. ); Rastorfer, J.R. . Dept. of Biological Sciences ANL Van Dyke, G.D. . Dept. of Biology)

    1991-07-01

    Implementation of recent federal and state regulations promulgated to protect wetlands makes information on effects of gas pipeline rights-of-way (ROWs) in wetlands essential to the gas pipeline industry. This study is designed to record vegetational changes induced by the construction of a large-diameter gas pipeline through deciduous forested wetlands. Two second-growth forested wetland sites mapped as Lenawee soils, one mature and one subjected to recent selective logging, were selected in Midland County, Michigan. Changes in the adjacent forest and successional development on the ROW are being documented. Cover-class estimates are being made for understory and ROW plant species using 1 {times}1-m quadrats. Counts are also being made for all woody species with stems < 2 cm in diameter at breast height (dbh) in the same plots used for cover-class estimates. Individual stem diameters and species counts are being recorded for all woody understory and overstory plants with stems {ge}2 cm dbh in 10 {times} 10-m plots. Although analyses of the data have not been completed, preliminary analyses indicate that some destruction of vegetation at the ROW forest edge may have been avoidable during pipeline construction. Rapid regrowth of many native wetland plant species on the ROW occurred because remnants of native vegetation and soil-bearing propagules of existing species survived on the ROW after pipeline construction and seeding operations. 91 refs., 11 figs., 3 tabs.

  4. Security during the Construction of New Nuclear Power Plants: Technical Basis for Access Authorization and Fitness-For-Duty Requirements

    SciTech Connect

    Branch, Kristi M.; Baker, Kathryn A.

    2009-09-01

    A technical letter report to the NRC summarizing the findings of a benchmarking study, literature review, and workshop with experts on current industry standards and expert judgments about needs for security during the construction phase of critical infrastructure facilities in the post-September 11 U.S. context, with a special focus on the construction phase of nuclear power plants and personnel security measures.

  5. Temperature effects on wastewater nitrate removal in laboratory-scale constructed wetlands

    SciTech Connect

    Wood, S.L.; Wheeler, E.F.; Berghage, R.D.; Graves, R.E.

    1999-02-01

    Constructed wetlands may be used for removal of high nutrient loads in greenhouse wastewater prior to discharge into the environment. Temperature affects both the physical and biological activities in wetland systems. Since nitrification and denitrification are temperature-dependent processes, effluent nitrate concentrations will fluctuate due to changes in air and wetland temperature. In a cold climate, constructed wetlands can function in a temperature-controlled, greenhouse environment year-round. This work evaluates four temperature treatments on nitrate removal rates in five planted and five unplanted laboratory-scale wetlands. Wetlands were supplied with a nutrient solution similar to the fertigation runoff solution (100 PPM nitrate-N) used in greenhouse crop production. A first-order kinetic model was used to describe experimental nitrate depletion data and to predict nitrate removal rate constants (k) in the wetlands planted with Iris pseudocoras. The negligible removal in unplanted wetlands was thought to be due to lack of carbon source in the fertigation solution. Between 19 and 23 C is planted systems, k increased from 0.062 to 0.077 h{sup {minus}1}, appeared to peak around 30 C (k = 0.184 h{sup {minus}1}), but decreased at 38 C (k = 0.099h{sup {minus}1}). Based on the Arrhenius equation, k was a first-order exponential function of temperature between 18 and 30 C in planted systems. Quantification of temperature effects on planted and unplanted laboratory-scale constructed wetlands can be sued to enhance the design and management of wastewater treatment wetlands.

  6. Construction and analysis of a plant non-specific lipid transfer protein database (nsLTPDB)

    PubMed Central

    2012-01-01

    Background Plant non-specific lipid transfer proteins (nsLTPs) are small and basic proteins. Recently, nsLTPs have been reported involved in many physiological functions such as mediating phospholipid transfer, participating in plant defence activity against bacterial and fungal pathogens, and enhancing cell wall extension in tobacco. However, the lipid transfer mechanism of nsLTPs is still unclear, and comprehensive information of nsLTPs is difficult to obtain. Methods In this study, we identified 595 nsLTPs from 121 different species and constructed an nsLTPs database -- nsLTPDB -- which comprises the sequence information, structures, relevant literatures, and biological data of all plant nsLTPs http://nsltpdb.life.nthu.edu.tw/. Results Meanwhile, bioinformatics and statistics methods were implemented to develop a classification method for nsLTPs based on the patterns of the eight highly-conserved cysteine residues, and to suggest strict Prosite-styled patterns for Type I and Type II nsLTPs. The pattern of Type I is C X2 V X5-7 C [V, L, I] × Y [L, A, V] X8-13 CC × G X12 D × [Q, K, R] X2 CXC X16-21 P X2 C X13-15C, and that of Type II is C X4 L X2 C X9-11 P [S, T] X2 CC X5 Q X2-4 C[L, F]C X2 [A, L, I] × [D, N] P X10-12 [K, R] X4-5 C X3-4 P X0-2 C. Moreover, we referred the Prosite-styled patterns to the experimental mutagenesis data that previously established by our group, and found that the residues with higher conservation played an important role in the structural stability or lipid binding ability of nsLTPs. Conclusions Taken together, this research has suggested potential residues that might be essential to modulate the structural and functional properties of plant nsLTPs. Finally, we proposed some biologically important sites of the nsLTPs, which are described by using a new Prosite-styled pattern that we defined. PMID:22369214

  7. The effectiveness of hearing protection among construction workers.

    PubMed

    Neitzel, Richard; Seixas, Noah

    2005-04-01

    Effective hearing conservation programs in the construction industry are rare. Where programs are present, they often rely on workers' use of hearing protection devices (HPDs) rather than on exposure controls to reduce noise exposure levels. Dependence on HPDs for protection from high noise is problematic, as the protection provided by the HPD depends on both the HPD's attenuation level and the time the HPD is used. This article presents an analysis of data on noise exposure and hearing protection among construction workers drawn from several large datasets covering nine construction trades. A unique combination of 1-min dosimetry noise exposure levels and simultaneous self-reported use of HPDs was evaluated, as were occupational and nonoccupational HPD use data collected by questionnaire as part of a longitudinal study of noise exposure and hearing loss among apprentices. Direct measurements of HPD attenuation were also made on workers at their work site. The workers assessed in this study were found to use hearing protection less than one-quarter of the time that they were exposed above 85 dBA. Workers who reported always using HPDs in high noise on questionnaires were found to wear them only one-third of the time their exposures exceeded 85 dBA. Workers' self-reported use of HPDs during most noisy nonoccupational activities was also found to be low. Direct attenuation measurements found that workers were able to achieve more than 50% of the rated attenuation of their HPD on average, but that the variability in achieved attenuation was large. When the measured HPD attenuation levels and use time data were combined, the effective protection afforded by HPDs was less than 3 dB, a negligible amount given the high exposure levels associated with construction work. However, there was substantial variation in effective protection among the different trades assessed. These results demonstrate the need for better hearing conservation programs and expanded noise control

  8. Pervasive and strong effects of plants on soil chemistry: a meta-analysis of individual plant ‘Zinke’ effects

    PubMed Central

    Waring, Bonnie G.; Álvarez-Cansino, Leonor; Barry, Kathryn E.; Becklund, Kristen K.; Dale, Sarah; Gei, Maria G.; Keller, Adrienne B.; Lopez, Omar R.; Markesteijn, Lars; Mangan, Scott; Riggs, Charlotte E.; Rodríguez-Ronderos, María Elizabeth; Segnitz, R. Max; Schnitzer, Stefan A.; Powers, Jennifer S.

    2015-01-01

    Plant species leave a chemical signature in the soils below them, generating fine-scale spatial variation that drives ecological processes. Since the publication of a seminal paper on plant-mediated soil heterogeneity by Paul Zinke in 1962, a robust literature has developed examining effects of individual plants on their local environments (individual plant effects). Here, we synthesize this work using meta-analysis to show that plant effects are strong and pervasive across ecosystems on six continents. Overall, soil properties beneath individual plants differ from those of neighbours by an average of 41%. Although the magnitudes of individual plant effects exhibit weak relationships with climate and latitude, they are significantly stronger in deserts and tundra than forests, and weaker in intensively managed ecosystems. The ubiquitous effects of plant individuals and species on local soil properties imply that individual plant effects have a role in plant–soil feedbacks, linking individual plants with biogeochemical processes at the ecosystem scale. PMID:26224711

  9. New practical and theoretical approaches to the induction of morphogenesis from plant tumors in vitro using new types of plant growth regulators: towards constructive paradigms in agriculture and medicine.

    PubMed

    Lieber, Michael M

    2013-01-01

    Using classical or traditional plant growth regulators, calli or plant tumors have been produced in vitro and subsequently have been induced to produce buds and plantlets, a process referred to as regeneration. For many years, this has been a successful procedure for in vitro, plant propagation. However, for a number of plant species investigators could not induce calli in vitro to produce buds. Organogenesis was still recalcitrant for various plants in 1980. New types or nonconventional growth regulators, such as methylglyoxal and ascorbic acid, were then found to overcome recalcitrant organogenesis in vitro. Their successful or effective use gave support to a theory that stressful, non-uniform cohesive force-fields, electromagnetic in nature, occurring through the application of certain chemicals, are necessary for in vitro morphogenesis from plant neoplasm or callus. Morphogenesis is seen as an adaptive accommodation to the inner stresses from such non-uniform, cohesive forces. Diverse chemicals, not considered traditional plant growth regulators would, it has been conjectured, enable the generation of such cohesive forces, in non-uniform arrays, and it has been predicted that more chemicals of this type will be discovered. A new constructive approach to agriculture and medicine, using a new plant tissue-culture model, based on new theory, has also been predicted.

  10. Perceived heat stress and health effects on construction workers

    PubMed Central

    Dutta, Priya; Rajiva, Ajit; Andhare, Dileep; Azhar, Gulrez Shah; Tiwari, Abhiyant; Sheffield, Perry

    2015-01-01

    Introduction: Increasing heat waves-particularly in urban areas where construction is most prevalent, highlight a need for heat exposure assessment of construction workers. This study aims to characterize the effects of heat on construction workers from a site in Gandhinagar. Materials and Methods: This study involved a mixed methods approach consisting of a cross sectional survey with anthropometric measurements (n = 219) and four focus groups with construction workers, as well as environmental measurements of heat stress exposure at a construction site. Survey data was collected in two seasons i.e., summer and winter months, and heat illness and symptoms were compared between the two time periods. Thematic coding of focus group data was used to identify vulnerability factors and coping mechanisms of the workers. Heat stress, recorded using a wet bulb globe temperature monitor, was compared to international safety standards. Results: The survey findings suggest that heat-related symptoms increased in summer; 59% of all reports in summer were positive for symptoms (from Mild to Severe) as compared to 41% in winter. Focus groups revealed four dominant themes: (1) Non-occupational stressors compound work stressors; (2) workers were particularly attuned to the impact of heat on their health; (3) workers were aware of heat-related preventive measures; and (4) few resources were currently available to protect workers from heat stress. Working conditions often exceed international heat stress safety thresholds. Female workers and new employees might be at increased risk of illness or injury. Conclusion: This study suggests significant health impacts on construction workers from heat stress exposure in the workplace, showed that heat stress levels were higher than those prescribed by international standards and highlights the need for revision of work practices, increased protective measures, and possible development of indigenous work safety standards for heat exposure

  11. A global meta-analytic contrast of cushion-plant effects on plants and on arthropods.

    PubMed

    Liczner, Amanda R; Lortie, Christopher J

    2014-01-01

    Nurse plant facilitation is a commonly reported plant-plant interaction and is an important factor influencing community structure in stressful environments. Cushion plants are an example of alpine nurse plants that modify microclimatic conditions within their canopies to create favourable environments for other plants. In this meta-analysis, the facilitative effects of cushion plants was expanded from previous syntheses of the topic and the relative strength of facilitation for other plants and for arthropods were compared globally.The abundance, diversity, and species presence/absence effect size estimates were tested as plant responses to nurse plants and a composite measure was tested for arthropods. The strength of facilitation was on average three times greater for arthropods relative to all plant responses to cushions. Plant species presence, i.e., frequency of occurrence, was not enhanced by nurse-plants. Cushion plants nonetheless acted as nurse plants for both plants and arthropods in most alpine contexts globally, and although responses by other plant species currently dominate the facilitation literature, preliminary synthesis of the evidence suggests that the potential impacts of nurses may be even greater for other trophic levels.

  12. Construction of the thermal/structural interactions in situ tests at the Waste Isolation Pilot Plant (WIPP)

    SciTech Connect

    Munson, D.E.; Matalucci, R.V.; Hoag, D.L.; Blankenship D.A.

    1997-02-01

    The Department of Energy has constructed the Waste Isolation Pilot Plant (WIPP) to develop the technology for the disposal of radioactive waste from defense programs. Sandia National Laboratories has the responsibility for experimental activities at the WIPP and has emplaced several large-scale Thermal/Structural Interactions (TSI) in situ tests to validate techniques used to predict repository performance. The construction of the tests relied heavily on earlier excavations at the WIPP site to provide a basis for selecting excavation, surveying, and instrumentation methods, and achievable construction tolerances. The tests were constructed within close tolerances to provide consistent room dimensions and accurate placement of gages. This accuracy has contributed to the high quality of data generated which in turn has facilitated the comparison of test results to numerical predictions. The purpose of this report is to detail the construction activities of the TSI tests.

  13. A Systematic Review of Iran's Medicinal Plants With Anticancer Effects.

    PubMed

    Asadi-Samani, Majid; Kooti, Wesam; Aslani, Elahe; Shirzad, Hedayatollah

    2016-04-01

    Increase in cases of various cancers has encouraged the researchers to discover novel, more effective drugs from plant sources. This study is a review of medicinal plants in Iran with already investigated anticancer effects on various cell lines. Thirty-six medicinal plants alongside their products with anticancer effects as well as the most important plant compounds responsible for the plants' anticancer effect were introduced. Phenolic and alkaloid compounds were demonstrated to have anticancer effects on various cancers in most studies. The plants and their active compounds exerted anticancer effects by removing free radicals and antioxidant effects, cell cycle arrest, induction of apoptosis, and inhibition of angiogenesis. The investigated plants in Iran contain the compounds that are able to contribute effectively to fighting cancer cells. Therefore, the extract and active compounds of the medicinal plants introduced in this review article could open a way to conduct clinical trials on cancer and greatly help researchers and pharmacists develop new anticancer drugs.

  14. TRICHLOROETHYLENE REMOVAL FROM GROUNDWATER IN FLOW-THROUGH COLUMNS SIMULATING A PERMEABLE REACTIVE BARRIER CONSTRUCTED WITH PLANT MULCH

    EPA Science Inventory

    Ground water contaminated with TCE is commonly treated with a passive reactive barrier (PRB) constructed with zero-valence iron. The cost of iron as the reactive matrix has driven a search for less costly alternatives, and composted plant mulch has been used as an alternative re...

  15. Loss of Plant Biodiversity Over a Seven-Year Period in Two Constructed Wetlands in Central New York

    NASA Astrophysics Data System (ADS)

    Kearney, Miranda A.; Fickbohm, Scott; Zhu, Weixing

    2013-05-01

    Since wetland construction projects are becoming more commonplace, meaningful follow-up studies are needed to evaluate how these systems change over time. To that end, the objective of our study was to examine the temporal changes in plant community composition and water chemistry in two constructed wetlands. We investigated two wetland sites that were constructed in 2003 in northern Otsego County, NY, a county that is largely dominated by agriculture. Site 1 was previously an active cow pasture and site 2 was previously a wet meadow surrounded by agricultural fields. No active plant introduction was made during the construction; however, both sites were located in areas with many remnant wetlands and were connected to through-flowing streams. In 2004 (Year 1) and 2010 (Year 7), the plant community composition and nitrogen retention were assessed. We found that both sites experienced site-wide declines in plant species richness, including the loss of upland and facultative upland species and the unanticipated loss of facultative wetland and some obligate species. We propose that high water levels, which, at their maximum depth were >1.5 m deeper than in Year 1, maintained by landowners in the years after the initial survey, may have been responsible for the unexpected loss of wetland species. We also found that site 1 exhibited considerable nitrogen retention in both Year 1 and Year 7; however, N concentrations were low at site 2 in both years.

  16. Loss of plant biodiversity over a seven-year period in two constructed wetlands in Central New York.

    PubMed

    Kearney, Miranda A; Fickbohm, Scott; Zhu, Weixing

    2013-05-01

    Since wetland construction projects are becoming more commonplace, meaningful follow-up studies are needed to evaluate how these systems change over time. To that end, the objective of our study was to examine the temporal changes in plant community composition and water chemistry in two constructed wetlands. We investigated two wetland sites that were constructed in 2003 in northern Otsego County, NY, a county that is largely dominated by agriculture. Site 1 was previously an active cow pasture and site 2 was previously a wet meadow surrounded by agricultural fields. No active plant introduction was made during the construction; however, both sites were located in areas with many remnant wetlands and were connected to through-flowing streams. In 2004 (Year 1) and 2010 (Year 7), the plant community composition and nitrogen retention were assessed. We found that both sites experienced site-wide declines in plant species richness, including the loss of upland and facultative upland species and the unanticipated loss of facultative wetland and some obligate species. We propose that high water levels, which, at their maximum depth were >1.5 m deeper than in Year 1, maintained by landowners in the years after the initial survey, may have been responsible for the unexpected loss of wetland species. We also found that site 1 exhibited considerable nitrogen retention in both Year 1 and Year 7; however, N concentrations were low at site 2 in both years.

  17. [Construction effect of fertile cultivated layer in black soil].

    PubMed

    Han, Xiao-zeng; Zou, Wen-xiu; Wang, Feng-xian; Wang, Feng-ju

    2009-12-01

    The clayey farmland soil in black soil region of Northeast China, due to the existence of thicker plough pan created by unreasonable tillage, is a main limiting factor for local agricultural production. In this paper, a field experiment was conducted to study the construction effect of fertile cultivated layer on crop yield, soil physical properties, soil moisture content, and soil microbial number. After the construction of fertile cultivated layer, the soil had a thicker cultivated layer, and the crop yield was increased. Comparing with traditional tillage, applying straw and organic manure into 20-35 cm soil layer decreased soil bulk density by 9.88% and 6.20%, increased soil porosity by 9.58% and 6.02%, and enhanced soil saturated hydraulic conductivity by 167.99 and 73.78%, respectively, indicating that the construction of fertile cultivated layer could improve soil aeration and water permeability, and enhance the infiltration of rainfall. The soil moisture content and water use efficiency under the application of straw and organic manure into plough pan were higher than those under traditional tillage, and a positive correlation was observed between the moisture content in 0-35 cm soil layer and the emergence of maize seedlings. Due to the increased organic carbon source and aeration in the constructed fertile cultivated layer, soil microbial number was also increased.

  18. Plant inter-species effects on rhizosphere priming effect and nitrogen acquisition by plants

    NASA Astrophysics Data System (ADS)

    Sun, Yue; Xu, Xingliang; Yang, Baijie; Kuzyakov, Yakov

    2015-04-01

    Rhizosphere interactions play a central role linking roots-soil system and regulate various aspects of nutrient cycling. Rhizodeposition inputs are known to change soil organic matter (SOM) decomposition via rhizosphere priming effects (RPEs) through enhancing soil biological activity and altering microbial community structure. The magnitude of RPEs varies widely among plant-species and root biomass possibly due to different quality and quantity of rhizodeposits. However, it is virtually unknown whether the RPEs are influenced by plant inter-species interactions and how these processes affect N mineralization and available N for plants. Monocultures of maize (M) and soybean (S), and mixed cultures of maize/maize (MM), soybean/soybean (SS), maize/soybean (MS) were grown over a 45-day greenhouse experiment. We labeled them with plant litter that was enriched in13C and 15N. The 15N distributions in plants and microbial biomass were measured at 14, 35, and 45days after labeling. The RPEs were positive under all plants, ranging from 11.7% to 138.3% and gradually decreased with plant growth. The RPE in the SS was significantly higher than these in others treatments at 14 days, while at 45 days it was higher in the MS than these from their monocultures, suggesting that the RPE was enhanced by the inter-species effects of maize and soybean. The litter decomposition ratio and 15N recovery of plants and microorganism increased with the root growth across all plants. The 15N recovery of plants in the MS (14.2%) was higher than these in the MM (12.3%) and SS(9.7%) at 45 days. Similarly, the 15N recovery of microorganism in the corresponding treatments was 6.7%, 2.2%, and 6.8%, respectively. The MS showed higher soil organic N mineralization amount than that from all soybean and maize monocultures at 45 days. We conclude that plant inter-species interactions may have significant effect on rhizosphere priming and modify the plant N uptake from litter resource and SOM.

  19. TANK OPERATIONS CONTRACT CONSTRUCTION MANAGEMENT METHODOLOGY UTILIZING THE AGENCY METHOD OF CONSTRUCTION MANAGEMENT TO SAFELY AND EFFECTIVELY COMPLETE NUCLEAR CONSTRUCTION WORK

    SciTech Connect

    LESO KF; HAMILTON HM; FARNER M; HEATH T

    2010-01-14

    Washington River Protection Solutions, LLC (WRPS) has faced significant project management challenges in managing Davis-Bacon construction work that meets contractually required small business goals. The unique challenge is to provide contracting opportunities to multiple small business construction subcontractors while performing high hazard work in a safe and productive manner. Previous to the Washington River Protection Solutions, LLC contract, Construction work at the Hanford Tank Farms was contracted to large companies, while current Department of Energy (DOE) Contracts typically emphasize small business awards. As an integral part of Nuclear Project Management at Hanford Tank Farms, construction involves removal of old equipment and structures and installation of new infrastructure to support waste retrieval and waste feed delivery to the Waste Treatment Plant. Utilizing the optimum construction approach ensures that the contractors responsible for this work are successful in meeting safety, quality, cost and schedule objectives while working in a very hazardous environment. This paper describes the successful transition from a traditional project delivery method that utilized a large business general contractor and subcontractors to a new project construction management model that is more oriented to small businesses. Construction has selected the Agency Construction Management Method. This method was implemented in the first quarter of Fiscal Year (FY) 2009, where Construction Management is performed by substantially home office resources from the URS Northwest Office in Richland, Washington. The Agency Method has allowed WRPS to provide proven Construction Managers and Field Leads to mentor and direct small business contractors, thus providing expertise and assurance of a successful project. Construction execution contracts are subcontracted directly by WRPS to small or disadvantaged contractors that are mentored and supported by DRS personnel. Each small

  20. Coliform bacteria removal from sewage in constructed wetlands planted with Mentha aquatica.

    PubMed

    Avelar, Fabiana F; de Matos, Antonio T; de Matos, Mateus P; Borges, Alisson C

    2014-08-01

    The present study evaluated the performance of the species Mentha aquatica in constructed wetlands of horizontal subsurface flow (CW-HSSF) with regard to the removal of coliforms bacteria in an effluent from the primary treatment of sewage as well as to obtain adjustment parameters of the bacterial decay kinetic model along the length of the CW-HSSF. Therefore, four CW-HSSFs measuring 24.0 m x 1.0 m x 0.35 m were built and filled with number 0 gravel as the support medium to a height of 0.20m. Two of the CW-HSSFs were planted with the species M. aquatica, while the other two remained uncultivated. Cultivation of M. aquatica in CW-HSSF resulted in total coliforms (TC) and Escherichia coli (EC) removals from 0.9 to 1.3 log units greater than those obtained in the uncultivated experimental plots, for the hydraulic retention times (HRTs) of 4.5 and 6.0 days. For HRT ranged from 1.5 to 6.0 days, the highest removal efficiencies in counts of TC and EC were obtained when using longer HRT. The mathematical models evaluated showed good fit to average counts of TC and EC highlighting the modified first-order kinetic model with the inclusion of the power parameter in the HRT variable.

  1. PAHs in leachates from thermal power plant wastes and ash-based construction materials.

    PubMed

    Irha, Natalya; Reinik, Janek; Jefimova, Jekaterina; Koroljova, Arina; Raado, Lembi-Merike; Hain, Tiina; Uibu, Mai; Kuusik, Rein

    2015-08-01

    The focus of the current study is to characterise the leaching behaviour of polycyclic aromatic hydrocarbons (PAHs) from oil shale ashes (OSAs) of pulverised firing (PF) and circulating fluidised-bed (CFB) boilers from Estonian Thermal Power Plant (Estonia) as well as from mortars and concrete based on OSAs. The target substances were 16 PAHs from the EPA priority pollutant list. OSA samples and OSA-based mortars were tested for leaching, according to European standard EN 12457-2 (2002). European standard CEN/TC 15862(2012) for monolithic matter was used for OSA-based concrete. Water extracts were analysed by GC-MS for the concentration of PAHs. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene were detected. Still, the release of PAHs was below the threshold limit value for inert waste. The amount of the finest fraction (particle size <0.045 mm), the content of the Al-Si glass phase and the surface characteristics were the main factors, which could affect the accessibility of PAHs for leaching. The mobility of PAHs from OSA of CFB and PF boilers was 20.2 and 9.9%, respectively. Hardening of OSA-based materials did not lead to the immobilisation of soluble PAHs. Release of PAHs from the monolith samples did not exceed 0.5 μg/m(2). In terms of leaching of PAHs, OSA is safe to be used for construction purposes.

  2. Evaluation of the biotic potential of microorganisms and higher plants to enhance the quality of constructed wetlands. Final report

    SciTech Connect

    Mays, D.A.; Floyd, M.; Taylor, R.W.; Sistani, K.

    1998-09-30

    A project was carried out from October 1, 1991 through September 30, 1998 to evaluate the growth of several species of wetland plants in constructed cells using mine spoil as a growth medium, to evaluate microbial diversity and finally, to demonstrate the concept on an actual strip-mined site. In order to gain background information for evaluation of constructed wetlands, several wetlands on both undisturbed and strip-mined areas were evaluated to determine the physical and chemical characteristics of the substrates as well as the vegetation characteristics. The research phase of this projects consisted of 10 wetland cells each 7x16 m in size with the water depth varying from 0 to 40 cm. The substrates were allowed to stabilize over winter and each cell was planted in the spring of 1993 with 18 plants each of cattail, maidencance, soft stem bulrush and pickerel weed. All cells were thickly vegetated by the end of the first growing season.

  3. Secondary succession of arthropods and plants in the Arizona Sonoran Desert in response to transmission-line construction

    SciTech Connect

    Johnson, C.D.; Beley, J.R.; Ditsworth, T.M.; Butt, S.M.

    1983-03-01

    At a site about 16 km south of Black Canyon City, Arizona, density of arthropods on an undisturbed plot after an access road was built for powerline construction was much greater than on a disturbed plot. Mites, springtails, leafhoppers, scale insects, ants and thrips were significantly reduced on the disturbed area. Diversity increased on the disturbed plot after construction, but density decreased. A slight increase in similarity (H', Clambda) of the arthropod communities of the two plots appears to be related to the modest increase in cover on the disturbed area. Globe-mallow, goosefoot and a four-o'clock were pioneer species and occurred only on the disturbed area. There was a significant reduction in cover of all plant species on the disturbed plot after construction, but there was a steady increase of annual forbs at the end of the study. The results indicate that restoration of numbers of arthropods on the disturbed area is dependent on the total plant cover on the plot, apparently regardless of the composition of the plant species involved. It is obvious in this area that the plant communities will remain dissimilar, with the pioneering herbaceous plants on the disturbed plot dominating. Construction of a powerline apparently has had little impact on the structure of the arthropod community on the disturbed area, as proportions of three trophic categories of arthropods have not been radically altered. The results of this study, when compared to other studies in the Sonoran Desert and in desert grasslands disturbed by powerline construction, indicate that lengthy secondary succession does occur in the Sonoran Desert. Early arthropod invaders were found to be mainly herbivores, with few parasites or predators, and an equilibrium was eventually reached between colonizers and space requirements. 35 references, 3 figures, 3 tables

  4. Constructing equivalent effective chiral Lagrangians: A systematic approach

    SciTech Connect

    Kang, K. ); Pantziris, A. . Department of Physics Brooklyn College of the City University of New York, Brooklyn, New York . Center for Nuclear Theory)

    1991-01-01

    We demonstrate a systematic method of constructing physically equivalent effective chiral Lagrangians based on the symmetry properties of low-energy hadron physics. We start by building the most general Lagrangian describing pion-nucleon systems within the chiral SU(2){sub {ital L}}{times}SU(2){sub {ital R}} context. The symmetry is then enlarged to include additional Goldstone bosons such as the axion of the Peccei-Quinn symmetry. The vector and axial-vector mesons are introduced in the context of a gauge chiral model for completeness. We work out explicitly a specific example of the equivalence of effective Lagrangian models for the nucleon-nucleon-axion bremsstrahlung process.

  5. Effect of loading rate on performance of constructed wetlands treating an anaerobic supernatant.

    PubMed

    Chazarenc, F; Maltais-Landry, G; Troesch, S; Comeau, Y; Brisson, J

    2007-01-01

    The effect of organic loading, season and plant species on the treatment of fish farm effluent was tested using three-year old mesocosm wetland systems. During one year, nine 1 m2 mesocosms (horizontal subsurface flow), located in a controlled greenhouse environment, were fed with a reconstituted fish farm effluent containing a high fraction of soluble components (1,600 microS/cm and in mg/L: 230 +/- 80 COD, 179 +/- 60 sCOD, 100 +/- 40 TSS, 37 +/- 7 TKN, 14 +/- 2 TP). Combinations of three hydraulic loading rates (30, 60 and 90 L.m(-2) d(-1)) and two plant species (Phragmites australis, Typha angustifolia) and an unplanted control were tested for treatment performance and hydraulic behaviour. Loadings higher than 15 g COD m(-2) d(-1) resulted in a net decrease of hydraulic performances (generation of short circuiting) coupled with low TKN removal. Maximal TKN removal rates (summer: 1.2, winter: 0.6 g.m(-2) d(-1)) were reached in planted units. In all mesocosms, phosphorus was removed during summer (maximal removal rate: 0.3 g TP m(-2) d(-1)) and was released in winter (release rate = approximately half of summer removal rate). This study confirmed that constructed wetlands are susceptible to clogging when treating anaerobic storage tank supernatant rich in highly biodegradable compounds. Contributions of plants to hydraulic efficiency were mainly observed in summer, associated with high evapotranspiration rates. Both plant species gave a similar removal efficiency for all pollutants.

  6. Seasonal effect on N2O formation in nitrification in constructed wetlands.

    PubMed

    Inamori, Ryuhei; Wang, Yanhua; Yamamoto, Tomoko; Zhang, Jixiang; Kong, Hainan; Xu, Kaiqin; Inamori, Yuhei

    2008-10-01

    Constructed wetlands are considered to be important sources of nitrous oxide (N(2)O). In order to investigate the contribution of nitrification in N(2)O formation, some environmental factors, plant species and ammonia-oxidizing bacteria (AOB) in active layers have been compared. Vegetation cells indicated remarkable effect of seasons and different plant species on N(2)O emission and AOB amount. Nitrous oxide data showed large temporal and spatial fluctuations ranging 0-52.8 mg N(2)O m(-2)d(-1). Higher AOB amount and N(2)O flux rate were observed in the Zizania latifolia cell, reflecting high potential of global warming. Roles of plants as ecosystem engineers are summarized with rhizosphere oxygen release and organic matter transportation to affect nitrogen transformation. The Phragmites australis cell contributed to keeping high T-N removal performance and lower N(2)O emission. The distribution of AOB also supported this result. Statistical analysis showed several environmental parameters affecting the strength of observed greenhouse gases emission, such as water temperature, water level, TOC, plant species and plant cover. PMID:18782640

  7. Nitrogen transformation in horizontal subsurface flow constructed wetlands II: Effect of biofilm

    NASA Astrophysics Data System (ADS)

    Bigambo, T.; Mayo, A. W.

    In this paper the significance of the biofilm biomass present in horizontal subsurface flow constructed wetland in removal of nitrogen was demonstrated. The model was developed and optimised using data obtained in a horizontal subsurface flow constructed wetland planted with Phragmites mauritianus and filled with 6-25 mm diameter gravel pack. The effects of biofilm biomass activities were studied by removing the effects of plant and gravel bed biofilm in an already calibrated model and re-run the same. Research results indicate that total nitrogen removal was largely influenced by growth of biofilm on plants than on aggregates. When plant biofilm and suspended biomasses were considered total nitrogen removal of 38.1% was observed compared with 25.1% when aggregate-biofilm and suspended biomasses were considered because plants have more surface areas, which are active sites for the effective biofilm activities than aggregates. However, in a natural wetland where the soil grain size is smaller, the effect of biofilm on plants may be smaller than biofilm on soil particles. There was no significant difference in organic-nitrogen effluent concentrations when biofilm biomass was considered or rejected. The averages in organic-nitrogen effluent concentrations were 0.39, 0.41 and 0.53 gN/m 2 for suspended alone, aggregate-biofilm and suspended; and suspended and plant-biofilm, respectively. This indicates that the removal of organic-nitrogen in wastewater is not significantly influenced by biofilm activities. Sedimentation and mineralization processes are the major factors influencing the concentration of organic-nitrogen in the effluent. On the other hand, biofilm activities had significant influence on ammonia-nitrogen and nitrate-nitrogen transformation. The developed model output indicates that the effluent ammonia concentration was 2 gN/m 2, but in absence of biofilm the effluent ammonia concentration increases to 3.5 gN/m 2. Statistical analysis indicates that the

  8. Effect of free fall on higher plants.

    NASA Technical Reports Server (NTRS)

    Gordon, S. A.

    1973-01-01

    The influence of exposure to the free-fall state on the orientation, morphogenesis, physiology, and radiation response of higher plants is briefly summarized. It is proposed that the duration of the space-flight experiments has been to brief to permit meaningful effects of free fall on general biochemistry, growth, and development to appear. However, two types of significant effect did occur. The first is on differential growth - i.e., tropism and epinasty - resulting from the absence of a normal geostimulus. For these phenomena it is suggested that ground-based experiments with the clinostat would suffice to mimic the effect of the free-fall state. The second is an apparent interaction between the radiation response and some flight condition, yielding an enhanced microspore abortion, a disturbed spindle function, and a stunting of stamen hairs. It is suggested that this apparent interaction may be derived from a shift in the rhythm of the cell cycle, induced by the free fall.

  9. Effects of plants containing secondary compounds and plant oils on rumen fermentation and ecology.

    PubMed

    Wanapat, Metha; Kongmun, Pongthon; Poungchompu, Onanong; Cherdthong, Anusorn; Khejornsart, Pichad; Pilajun, Ruangyote; Kaenpakdee, Sujittra

    2012-03-01

    A number of experiments have been conducted to investigate effects of tropical plants containing condensed tannins and/or saponins present in tropical plants and some plant oils on rumen fermentation and ecology in ruminants. Based on both in vitro and in vivo trials, the results revealed important effects on rumen microorganisms and fermentation including methane production. Incorporation and/or supplementation of these plants containing secondary metabolites have potential for improving rumen ecology and subsequently productivity in ruminants.

  10. Effect of N:P ratio of influent on biomass, nutrient allocation, and recovery of Typha latifolia and Canna 'Bengal Tiger' in a laboratory-scale constructed wetland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Constructed wetlands (CWs) are an effective low-technology approach for treating agricultural, industrial, and municipal wastewater. Recovery of phosphorous by constructed wetland plants may be affected by wastewater nitrogen to phosphorous (N:P) ratios. Varying N:P ratios were supplied to Canna '...

  11. Phenotypic plasticity of plant response to herbivore eggs: effects on resistance to caterpillars and plant development.

    PubMed

    Pashalidou, Foteini G; Lucas-Barbosa, Dani; van Loon, Joop J A; Dicke, Marcel; Fatouros, Nina E

    2013-03-01

    Herbivory induces direct resistance responses in plants that negatively affect subsequently colonizing herbivores. Moreover, eggs of herbivorous insects can also activate plant resistance, which in some cases prevents hatching larvae from feeding. Until now, plant-mediated effects of eggs on subsequent herbivory, and the specificity of such responses, have remained poorly understood. We studied the specificity and effects of plant resistance induced by herbivore egg deposition against lepidopteran larvae of species with different dietary breadths, feeding on a wild annual plant, the crucifer Brassica nigra. We examined whether this plant-mediated response affects the growth of caterpillars of a specialist (Pieris brassicae) that feeds on B. nigra leaves and flowers, and a generalist (Mamestra brassicae) that rarely attacks this wild crucifer. We measured growth rates of neonate larvae to the end of their second instar after the larvae had hatched on plants exposed to eggs vs. plants without eggs, under laboratory and semi-field conditions. Moreover, we studied the effects of egg deposition by the two herbivore species on plant height and flowering rate before and after larval hatching. Larvae of both herbivore species that developed on plants previously infested with eggs of the specialist butterfly P. brassicae gained less mass compared with larvae that developed on egg-free plants. Plants exposed to butterfly eggs showed accelerated plant growth and flowering compared to egg-free plants. Egg deposition by the generalist moth M. brassicae, in contrast, had no effect on subsequent performance by either herbivore species, or on plant development. Our results demonstrate that B. nigra plants respond differently to eggs of two herbivore species in terms of plant development and induced resistance to caterpillar attack. For this annual crucifer, the retardation of caterpillar growth in response to deposition of eggs by P. brassicae in combination with enhanced growth

  12. Phenotypic plasticity of plant response to herbivore eggs: effects on resistance to caterpillars and plant development.

    PubMed

    Pashalidou, Foteini G; Lucas-Barbosa, Dani; van Loon, Joop J A; Dicke, Marcel; Fatouros, Nina E

    2013-03-01

    Herbivory induces direct resistance responses in plants that negatively affect subsequently colonizing herbivores. Moreover, eggs of herbivorous insects can also activate plant resistance, which in some cases prevents hatching larvae from feeding. Until now, plant-mediated effects of eggs on subsequent herbivory, and the specificity of such responses, have remained poorly understood. We studied the specificity and effects of plant resistance induced by herbivore egg deposition against lepidopteran larvae of species with different dietary breadths, feeding on a wild annual plant, the crucifer Brassica nigra. We examined whether this plant-mediated response affects the growth of caterpillars of a specialist (Pieris brassicae) that feeds on B. nigra leaves and flowers, and a generalist (Mamestra brassicae) that rarely attacks this wild crucifer. We measured growth rates of neonate larvae to the end of their second instar after the larvae had hatched on plants exposed to eggs vs. plants without eggs, under laboratory and semi-field conditions. Moreover, we studied the effects of egg deposition by the two herbivore species on plant height and flowering rate before and after larval hatching. Larvae of both herbivore species that developed on plants previously infested with eggs of the specialist butterfly P. brassicae gained less mass compared with larvae that developed on egg-free plants. Plants exposed to butterfly eggs showed accelerated plant growth and flowering compared to egg-free plants. Egg deposition by the generalist moth M. brassicae, in contrast, had no effect on subsequent performance by either herbivore species, or on plant development. Our results demonstrate that B. nigra plants respond differently to eggs of two herbivore species in terms of plant development and induced resistance to caterpillar attack. For this annual crucifer, the retardation of caterpillar growth in response to deposition of eggs by P. brassicae in combination with enhanced growth

  13. Rainfall effects on rare annual plants

    USGS Publications Warehouse

    Levine, J.M.; McEachern, A.K.; Cowan, C.

    2008-01-01

    1. Variation in climate is predicted to increase over much of the planet this century. Forecasting species persistence with climate change thus requires understanding of how populations respond to climate variability, and the mechanisms underlying this response. Variable rainfall is well known to drive fluctuations in annual plant populations, yet the degree to which population response is driven by between-year variation in germination cueing, water limitation or competitive suppression is poorly understood. 2. We used demographic monitoring and population models to examine how three seed banking, rare annual plants of the California Channel Islands respond to natural variation in precipitation and their competitive environments. Island plants are particularly threatened by climate change because their current ranges are unlikely to overlap regions that are climatically favourable in the future. 3. Species showed 9 to 100-fold between-year variation in plant density over the 5-12 years of censusing, including a severe drought and a wet El Nin??o year. During the drought, population sizes were low for all species. However, even in non-drought years, population sizes and per capita growth rates showed considerable temporal variation, variation that was uncorrelated with total rainfall. These population fluctuations were instead correlated with the temperature after the first major storm event of the season, a germination cue for annual plants. 4. Temporal variation in the density of the focal species was uncorrelated with the total vegetative cover in the surrounding community, suggesting that variation in competitive environments does not strongly determine population fluctuations. At the same time, the uncorrelated responses of the focal species and their competitors to environmental variation may favour persistence via the storage effect. 5. Population growth rate analyses suggested differential endangerment of the focal annuals. Elasticity analyses and life

  14. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  15. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  16. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  17. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  18. 10 CFR 50.65 - Requirements for monitoring the effectiveness of maintenance at nuclear power plants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... maintenance at nuclear power plants. 50.65 Section 50.65 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Construction Permits § 50.65 Requirements for monitoring the effectiveness of maintenance at nuclear power..., including normal shutdown operations. (a)(1) Each holder of an operating license for a nuclear power...

  19. Effect of medicinal plants on wound healing.

    PubMed

    Budovsky, Arie; Yarmolinsky, Ludmila; Ben-Shabat, Shimon

    2015-01-01

    In the United States alone, chronic wounds affect 6.5 million patients. It is expected that the number of chronic wounds will increase worldwide due to the increase in age-related conditions and pathologies such as diabetes, obesity, and cardiovascular diseases. An estimated excess of US$25 billion is spent annually on treatment of chronic wounds, and the burden is rapidly growing due to increasing healthcare costs, an aging population, and a sharp rise in the incidence of diabetes and obesity worldwide. While current therapeutic agents have generally inadequate efficacy and number of serious adverse effects, the medicinal plants have been used in medicine since ancient times and are well known for their abilities to promote wound healing and prevent infection without grave side effects. Thus, herbal therapy may be an alternative strategy for treatment of wounds. The purpose of this review is to provide the verified data on the medicinal plants of the world flora with wound healing activity including the biologically active substances belonging to these herbal preparations and describe in detail the various cellular and molecular mechanisms of their actions.

  20. Effect of medicinal plants on wound healing.

    PubMed

    Budovsky, Arie; Yarmolinsky, Ludmila; Ben-Shabat, Shimon

    2015-01-01

    In the United States alone, chronic wounds affect 6.5 million patients. It is expected that the number of chronic wounds will increase worldwide due to the increase in age-related conditions and pathologies such as diabetes, obesity, and cardiovascular diseases. An estimated excess of US$25 billion is spent annually on treatment of chronic wounds, and the burden is rapidly growing due to increasing healthcare costs, an aging population, and a sharp rise in the incidence of diabetes and obesity worldwide. While current therapeutic agents have generally inadequate efficacy and number of serious adverse effects, the medicinal plants have been used in medicine since ancient times and are well known for their abilities to promote wound healing and prevent infection without grave side effects. Thus, herbal therapy may be an alternative strategy for treatment of wounds. The purpose of this review is to provide the verified data on the medicinal plants of the world flora with wound healing activity including the biologically active substances belonging to these herbal preparations and describe in detail the various cellular and molecular mechanisms of their actions. PMID:25703533

  1. Microgravity Effects on Plant Boundary Layers

    NASA Technical Reports Server (NTRS)

    Stutte, Gary; Monje, Oscar

    2005-01-01

    The goal of these series of experiment was to determine the effects of microgravity conditions on the developmental boundary layers in roots and leaves and to determine the effects of air flow on boundary layer development. It is hypothesized that microgravity induces larger boundary layers around plant organs because of the absence of buoyancy-driven convection. These larger boundary layers may affect normal metabolic function because they may reduce the fluxes of heat and metabolically active gases (e.g., oxygen, water vapor, and carbon dioxide. These experiments are to test whether there is a change in boundary layer associated with microgravity, quantify the change if it exists, and determine influence of air velocity on boundary layer thickness under different gravity conditions.

  2. The effect of heavy metals on nitrogen and oxygen demand removal in constructed wetlands.

    PubMed

    Lim, P E; Tay, M G; Mak, K Y; Mohamed, N

    2003-01-01

    The objective of this study is to investigate the respective effects of Zn, Pb and Cd as well as the combined effect of Zn, Pb, Cd and Cu on the removal of nitrogen and oxygen demand in constructed wetlands. Four laboratory-scale gravel-filled subsurface-flow constructed wetland units planted with cattails (Typha latifolia) were operated outdoors and fed with primary-treated domestic wastewater at a constant flow rate of 25 ml/min. After 6 months, three of the wetland units were fed with the same type of wastewater spiked with Zn(II), Pb(II) and Cd(II), respectively, at 20, 5 and 1 mg/l for a further 9 months. The remaining unit was fed with the same type of wastewater spiked with a combination of Zn(II), Pb(II), Cd(II) and Cu(II) at concentrations of 10, 2.5, 0.5 and 5 mg/l, respectively, over the same period. The chemical oxygen demand (COD) and ammoniacal nitrogen (AN) concentrations were monitored at the inlet, outlet and three additional locations along the length of the wetland units to assess the performance of the wetland units at various metal loadings. At the end of the study, all cattail plants were harvested for the determination of total Kjeldahl nitrogen and metal concentrations. The results showed that the COD removal efficiency was practically independent of increasing metal loading or a combination of metal loadings during the duration of the study. In contrast, the AN removal efficiency deteriorated progressively with increasing metal loading. The relative effect of the heavy metals was found to increase in the order: Zneffect of metals was not observed. The metals seem to exhibit some inhibitory effect on nitrogen uptake by cattail plants as indicated by lower nitrogen uptake rates in comparison to rates recorded in wetland systems treating domestic wastewater only.

  3. A potent effect of observational learning on chimpanzee tool construction

    PubMed Central

    Price, Elizabeth E.; Lambeth, Susan P.; Schapiro, Steve J.; Whiten, Andrew

    2009-01-01

    Although tool use occurs in diverse species, its complexity may mark an important distinction between humans and other animals. Chimpanzee tool use has many similarities to that seen in humans, yet evidence of the cumulatively complex and constructive technologies common in human populations remains absent in free-ranging chimpanzees. Here we provide the first evidence that chimpanzees have a latent capacity to socially learn to construct a composite tool. Fifty chimpanzees were assigned to one of five demonstration conditions that varied in the amount and type of information available in video footage of a conspecific. Chimpanzees exposed to complete footage of a chimpanzee combining the two components to retrieve a reward learned to combine the tools significantly more than those exposed to more restricted information. In a follow-up test, chimpanzees that constructed tools after watching the complete demonstration tended to do so even when the reward was within reach of the unmodified components, whereas those that spontaneously solved the task (without seeing the modification process) combined only when necessary. Social learning, therefore, had a powerful effect in instilling a marked persistence in the use of a complex technique at the cost of efficiency, inhibiting insightful tool use. PMID:19570785

  4. Discussion about the effect of digital plants library on the plants landscape restoration in Yuanmingyuan

    NASA Astrophysics Data System (ADS)

    Bing, L.; Guxin, S.; Gongli, L.

    2015-08-01

    Chinese classical garden emphasizes not only the construction of building, mountains and rivers, spring and stone landscape but also the selection and configuration mode of the plant species. Yuanmingyuan, a classical work of Chinese garden art, is of both the magnificence of northern royal garden and the delicacy of southern private garden. The plants landscape in Yuanmingyuan also has its own unique style. But it is regretful that after several disasters, it nearly disappears just as other building clusters. The Re- Yuanmingyuan group re-presents the plants landscape of Yuanmingyuan through investigation, restoration and three-dimensional space generation, and makes proposal about the concept of digital plants library for the first time with the expectation to provide basic support for the digital restoration of cultural heritage by establishing the plants library. The paper also introduces the process of digital plants library system construction as well as the significance of the library construction for the landscape restoration in Yuanmingyuan and even the northern royal garden.

  5. Cross-age effects on forensic face construction

    PubMed Central

    Fodarella, Cristina; Brown, Charity; Lewis, Amy; Frowd, Charlie D.

    2015-01-01

    The own-age bias (OAB) refers to recognition memory being more accurate for people of our own age than other age groups (e.g., Wright and Stroud, 2002). This paper investigated whether the OAB effect is present during construction of human faces (also known as facial composites, often for forensic/police use). In doing so, it adds to our understanding of factors influencing both facial memory across the life span as well as performance of facial composites. Participant-witnesses were grouped into younger (19–35 years) and older (51–80 years) adults, and constructed a single composite from memory of an own- or cross-age target face using the feature-based composite system PRO-fit. They also completed the shortened version of the glasgow face matching test (GFMT; Burton et al., 2010). A separate group of participants who were familiar with the relevant identities attempted to name the resulting composites. Correct naming of the composites revealed the presence of an OAB for older adults, who constructed more-identifiable composites of own-age than cross-age faces. For younger adults, age of target face did not influence correct naming and their composites were named at the same level as those constructed by older adults for younger targets. Also, there was no reliable correlation between face perception ability and composite quality. Overall, correct naming was fairly good across the experiment, and indicated benefit for older witnesses for older targets. Results are discussed in terms of contemporary theories of OAB, and implications of the work for forensic practice. PMID:26347697

  6. Accumulation of Metals and Boron in Phragmites australis Planted in Constructed Wetlands Polishing Real Electroplating Wastewater.

    PubMed

    Sochacki, Adam; Guy, Bernard; Faure, Olivier; Surmacz-Górska, Joanna

    2015-01-01

    The concentration of metals (Al, Cu, Fe, Mn, Ni, Zn) and B were determined in the above- and belowground biomass of Phragmites australis collected from the microcosm constructed wetland system used for the polishing of real electroplating wastewater. Translocation factor and bioconcentration factor were determined. Pearson correlation test was used to determine correlation between metal concentration in substrate and above- and belowground parts of Phragmites australis. The obtained results suggested that Phragmites australis did not play a major role as an accumulator of metals. It was observed also that the substrate could have exerted an effect on the translocation of Ni, Cu, Zn and Mn. The analysed concentrations of metals and B in biomass were in the range or even below the concentrations reported in the literature with the exception of Ni. The aboveground biomass was found suitable as a composting input in terms of metals concentrations.

  7. Belowground biodiversity effects of plant symbionts support aboveground productivity.

    PubMed

    Wagg, Cameron; Jansa, Jan; Schmid, Bernhard; van der Heijden, Marcel G A

    2011-10-01

    Soil microbes play key roles in ecosystems, yet the impact of their diversity on plant communities is still poorly understood. Here we demonstrate that the diversity of belowground plant-associated soil fungi promotes plant productivity and plant coexistence. Using additive partitioning of biodiversity effects developed in plant biodiversity studies, we demonstrate that this positive relationship can be driven by complementarity effects among soil fungi in one soil type and by a selection effect resulting from the fungal species that stimulated plant productivity the most in another soil type. Selection and complementarity effects among fungal species contributed to improving plant productivity up to 82% and 85%, respectively, above the average of the respective fungal species monocultures depending on the soil in which they were grown. These results also indicate that belowground diversity may act as insurance for maintaining plant productivity under differing environmental conditions.

  8. Demonstrating the Effects of Light Quality on Plant Growth.

    ERIC Educational Resources Information Center

    Whitesell, J. H.; Garcia, Maria

    1977-01-01

    Describes a lab demonstration that illustrates the effect of different colors or wavelengths of visible light on plant growth and development. This demonstration is appropriate for use in college biology, botany, or plant physiology courses. (HM)

  9. Nitrogen removal performance in planted and unplanted horizontal subsurface flow constructed wetlands treating different influent COD/N ratios.

    PubMed

    Wang, Wei; Ding, Yi; Ullman, Jeffrey L; Ambrose, Richard F; Wang, Yuhui; Song, Xinshan; Zhao, Zhimiao

    2016-05-01

    Microcosm horizontal subsurface flow constructed wetlands (HSSFCWs) were used to examine the impacts of vegetation on nitrogen dynamics treating different influent COD/N ratios (1:1, 4:1, and 8:1). An increase in the COD/N ratio led to increased reductions in NO3 and total inorganic nitrogen (TIN) in planted and unplanted wetlands, but diminished removal of NH4. The HSSFCW planted with Canna indica L. exhibited a significant reduction in NH4 compared to the unplanted system, particularly in the active root zone where NH4 removal performance increased by up to 26 % at the COD/N ratio of 8:1. There was no significant difference in NO3 removal between the planted and unplanted wetlands. TIN removal efficiency in the planted wetland increased with COD/N ratios, which was likely influenced by plant uptake. NH4 reductions were greater in planted wetland at the 20- and 40-cm depths while NO3 reductions were uniformly greater with depth in all cases, but no statistical difference was impacted by depth on TIN removal. These findings show that planting a HSSFCW can provide some benefit in reducing nitrogen loads in effluents, but only when a sufficient carbon source is present.

  10. Plant and root endophyte assembly history: interactive effects on native and exotic plants.

    PubMed

    Sikes, Benjamin A; Hawkes, Christine V; Fukami, Tadashi

    2016-02-01

    Differences in the arrival timing of plants and soil biota may result in different plant communities through priority effects, potentially affecting the success of native vs. exotic plants, but experimental evidence is largely lacking. We conducted a greenhouse experiment to investigate whether the assembly history of plants and fungal root endophytes could interact to influence plant emergence and biomass. We introduced a grass species and eight fungal species from one of three land-use types (undisturbed, disturbed, or pasture sites in a Florida scrubland) in factorial combinations. We then introduced all plants and fungi from the other land-use types 2 weeks later. Plant emergence was monitored for 6 months, and final plant biomass and fungal species composition assessed. The emergence and growth of the exotic Melinis repens and the native Schizacharyium niveum were affected negatively when introduced early with their "home" fungi, but early introduction of a different plant species or fungi from a different site type eliminated these negative effects, providing evidence for interactive priority effects. Interactive effects of plant and fungal arrival history may be an overlooked determinant of plant community structure and may provide an effective management tool to inhibit biological invasion and aid ecosystem restoration. PMID:27145622

  11. Plant and root endophyte assembly history: interactive effects on native and exotic plants.

    PubMed

    Sikes, Benjamin A; Hawkes, Christine V; Fukami, Tadashi

    2016-02-01

    Differences in the arrival timing of plants and soil biota may result in different plant communities through priority effects, potentially affecting the success of native vs. exotic plants, but experimental evidence is largely lacking. We conducted a greenhouse experiment to investigate whether the assembly history of plants and fungal root endophytes could interact to influence plant emergence and biomass. We introduced a grass species and eight fungal species from one of three land-use types (undisturbed, disturbed, or pasture sites in a Florida scrubland) in factorial combinations. We then introduced all plants and fungi from the other land-use types 2 weeks later. Plant emergence was monitored for 6 months, and final plant biomass and fungal species composition assessed. The emergence and growth of the exotic Melinis repens and the native Schizacharyium niveum were affected negatively when introduced early with their "home" fungi, but early introduction of a different plant species or fungi from a different site type eliminated these negative effects, providing evidence for interactive priority effects. Interactive effects of plant and fungal arrival history may be an overlooked determinant of plant community structure and may provide an effective management tool to inhibit biological invasion and aid ecosystem restoration.

  12. Vaccine antigen production in transgenic plants: strategies, gene constructs and perspectives.

    PubMed

    Sala, Francesco; Manuela Rigano, M; Barbante, Alessandra; Basso, Barbara; Walmsley, Amanda M; Castiglione, Stefano

    2003-01-30

    Stable integration of a gene into the plant nuclear or chloroplast genome can transform higher plants (e.g. tobacco, potato, tomato, banana) into bioreactors for the production of subunit vaccines for oral or parental administration. This can also be achieved by using recombinant plant viruses as transient expression vectors in infected plants. The use of plant-derived vaccines may overcome some of the major problems encountered with traditional vaccination against infectious diseases, autoimmune diseases and tumours. They also offer a convenient tool against the threat of bio-terrorism. State of the art, experimental strategies, safety and perspectives are discussed in this article.

  13. Balance of plant for SOFC experiences with the planning, engineering, construction and testing of a 10 kW planar SOFC pilot plant

    SciTech Connect

    Klov, K.; Sundal, P.; Monsen, T.; Vik, A.

    1996-12-31

    The Statoil Solide Oxide Fuel Cell Research Program was started in January 1991. Some results from this Program were presented to the 1994 Fuel Cell Seminar in San Diego. The final technical milestone for the program was to design, engineer, construct and test a 10 kW pilot plant. From the very beginning, the importance of coordination and integration in the development of components, subsystems and systems, combined with basic research on cell and stack performance, were established as the guidelines for the program. In this way the progress towards the final goal was not a matter of making the best individual cell, the best stack or a superior balance of plant, but to build an efficient, reliable and operative pilot plant system, and thus make a further step towards a verification of commercial SOFC system technology.

  14. Semantics of the transitive construction: prototype effects and developmental comparisons.

    PubMed

    Ibbotson, Paul; Theakston, Anna L; Lieven, Elena V M; Tomasello, Michael

    2012-01-01

    This paper investigates whether an abstract linguistic construction shows the kind of prototype effects characteristic of non-linguistic categories, in both adults and young children. Adapting the prototype-plus-distortion methodology of Franks and Bransford (1971), we found that whereas adults were lured toward false-positive recognition of sentences with prototypical transitive semantics, young children showed no such effect. We examined two main implications of the results. First, it adds a novel data point to a growing body of research in cognitive linguistics and construction grammar that shows abstract linguistic categories can behave in similar ways to non-linguistic categories, for example, by showing graded membership of a category. Thus, the findings lend psychological validity to the existing cross-linguistic evidence for prototypical transitive semantics. Second, we discuss a possible explanation for the fact that prototypical sentences were processed differently in adults and children, namely, that children's transitive semantic network is not as interconnected or cognitively coherent as adults'.

  15. Analysis of chemical reaction kinetics of depredating organic pollutants from secondary effluent of wastewater treatment plant in constructed wetlands.

    PubMed

    Wang, Hao; Jiang, Dengling; Yang, Yong; Cao, Guoping

    2013-01-01

    Four subsurface constructed wetlands were built to treat the secondary effluent of a wastewater treatment plant in Tangshan, China. The chemical pollutant indexes of chemical oxygen demand (COD) were analyzed to evaluate the removal efficiency of organic pollutants from the secondary effluent of the wastewater treatment plant. In all cases, the subsurface constructed wetlands were efficient in treating organic pollutants. Under the same hydraulic loading condition, the horizontal flow wetlands exhibited better efficiency of COD removal than vertical flow wetlands: the removal rates in horizontal flow wetlands could be maintained at 68.4 ± 2.42% to 92.2 ± 1.61%, compared with 63.8 ± 1.19% to 85.0 ± 1.25% in the vertical flow wetlands. Meanwhile, the chemical reaction kinetics of organic pollutants was analyzed, and the results showed that the degradation courses of the four subsurface wetlands all corresponded with the first order reaction kinetics to a large extent.

  16. Effects of open water on the performance of a constructed wetland for nonpoint source pollution control.

    PubMed

    Kim, H C; Yoon, C G; Son, Y K; Rhee, H P; Lee, S B

    2010-01-01

    The seasonal performance of four differently configured constructed wetland systems was compared for the treatment efficiency of nonpoint source pollution. Dead plants in the constructed wetlands increased the nitrogen removal rate during winter by providing organic carbon, which is essential for the denitrification process. However, when the wetlands released phosphorus from the dead plants, the removal rate of phosphorus decreased. After seven growing seasons, plant coverage was nearly 100%, and the dissolved oxygen (DO) concentration was lowered to 1.3-5.4 mg/L. Open-water sections were then constructed inside the wetlands, which resulted in enhanced DO concentrations as well as improved treatment efficiency of nutrients and biochemical oxygen demand (BOD). Overall, performance of the constructed wetland was improved BOD, total nitrogen, and total phosphorus with the establishment of open water sections in the constructed wetland system.

  17. Influence of season and plant species on the abundance and diversity of sulfate reducing bacteria and ammonia oxidizing bacteria in constructed wetland microcosms.

    PubMed

    Faulwetter, Jennifer L; Burr, Mark D; Parker, Albert E; Stein, Otto R; Camper, Anne K

    2013-01-01

    Constructed wetlands offer an effective means for treatment of wastewater from a variety of sources. An understanding of the microbial ecology controlling nitrogen, carbon and sulfur cycles in constructed wetlands has been identified as the greatest gap for optimizing performance of these promising treatment systems. It is suspected that operational factors such as plant types and hydraulic operation influence the subsurface wetland environment, especially redox, and that the observed variation in effluent quality is due to shifts in the microbial populations and/or their activity. This study investigated the biofilm associated sulfate reducing bacteria and ammonia oxidizing bacteria (using the dsrB and amoA genes, respectively) by examining a variety of surfaces within a model wetland (gravel, thick roots, fine roots, effluent), and the changes in activity (gene abundance) of these functional groups as influenced by plant species and season. Molecular techniques were used including quantitative PCR and denaturing gradient gel electrophoresis (DGGE), both with and without propidium monoazide (PMA) treatment. PMA treatment is a method for excluding from further analysis those cells with compromised membranes. Rigorous statistical analysis showed an interaction between the abundance of these two functional groups with the type of plant and season (p < 0.05). The richness of the sulfate reducing bacterial community, as indicated by DGGE profiles, increased in planted vs. unplanted microcosms. For ammonia oxidizing bacteria, season had the greatest impact on gene abundance and diversity (higher in summer than in winter). Overall, the primary influence of plant presence is believed to be related to root oxygen loss and its effect on rhizosphere redox.

  18. Assessing the effectiveness of a constructed Arctic stream using multiple biological attributes.

    PubMed

    Jones, Nicholas E; Scrimgeour, Garry J; Tonn, William M

    2008-12-01

    Objective assessment of habitat compensation is a central yet challenging issue for restoration ecologists. In 1997, a 3.4-km stream channel, designed to divert water around an open pit diamond mine, was excavated in the Barrenlands region of the Canadian Arctic to create productive stream habitat. We evaluated the initial success of this compensation program by comparing multiple biological attributes of the constructed stream during its first three years to those of natural reference streams in the area. The riparian zone of the constructed stream was largely devoid of vegetation throughout the period, in contrast to the densely vegetated zones of reference streams. The constructed stream also contained lower amounts of woody debris, coarse particulate organic matter (CPOM), and epilithon; had lower coverage by macrophytes and bryophytes; and processed leaf litter at a lower rate than reference streams. Species richness and densities of macroinvertebrates were consistently lower in the constructed stream compared to natural streams. This contributed to differences in macroinvertebrate assemblage structure throughout the period, although assemblages showed some convergence by year 3. The effectiveness of the constructed stream to emulate natural streams varied somewhat depending on the biological attribute being evaluated. Assessments based on individual attributes showed that minimal to moderate levels of similarity between the constructed stream and natural streams were achieved. A collective assessment of all biological and ecosystem attributes suggested that the constructed stream was not a good surrogate for natural streams during these first years. Additional time would be required before many characteristics of the constructed stream would resemble those of reference streams. Because initial efforts to improve fish habitat in the constructed stream focused on physical structures (e.g., weirs, vanes, rock, groins), ecological factors limiting fish growth

  19. Differential gene expression in nematode-induced feeding structures of transgenic plants harbouring promoter-gusA fusion constructs.

    PubMed

    Goddijn, O J; Lindsey, K; van der Lee, F M; Klap, J C; Sijmons, P C

    1993-11-01

    Sedentary plant-parasitic nematodes are able to induce specialized feeding structures in the root system of their host plants by triggering a series of dramatic cellular responses. These changes presumably are accompanied by a reprogramming of gene expression. To monitor such changes, a variety of promoter-gusA fusion constructs were introduced into Arabidopsis and tobacco. Transgenic plants were analysed histochemically for GUS activity in the nematode feeding structures after infection with either Heterodera schachtii or Meloidogyne incognita. Promoters of the Cauliflower Mosaic Virus 35S gene, the bacterial nopaline synthase, rooting loci (rol) and T-cyt genes and the plant-derived phenylalanine ammonia-lyase I gene, which are highly active in non-infected roots, were all downregulated in the feeding structures as indicated by the strong decrease of GUS activity inside these structures. Less stringent downregulation was observed with chimeric gusA fusion constructs harbouring truncated rolB and rolC promoter sequences. Similar observations were made with transgenic Arabidopsis lines that carried randomly integrated promoterless gusA constructs to identify regulatory sequences in the plant genome. Most of the lines that were selected for expression in the root vascular cylinder demonstrated local downregulation in feeding structures after infection with H. schachtii. The reverse pattern of GUS activity, a blue feeding structure amidst unstained root cells, was also found in several lines. However, GUS activity that was entirely specific for the feeding structures was not observed. Our data show that the expression of a large number of genes is influenced during the development of the nematode feeding structures.

  20. Effect of power plant emissions on plant community structure.

    PubMed

    Singh, J; Agrawal, M; Narayan, D

    1994-06-01

    A field study was conducted around two coal-fired thermal power plants (TPP) to analyse the impact of their emission on the structure of herbaceous communities in a dry tropical area. Phytosociological studies reflected that Cassia tora, Cynodon dactylon and Dichanthium annulatum dominate at heavily polluted sites. Alsycarpus monilifer, Convolvulus pluricaulis, and Desmodium triflorum are uniformly distributed, whereas Paspalidium flavidum, Phyllanthus simplex, and Rungia repens are dominant at less polluted sites. On the basis of Importance Value Index, the species were classified as sensitive, intermediate and resistant to TPP emissions. Shannon-Wiener Index of species diversity, species richness and evenness were inversely related, whereas concentration of dominance was directly related to the pollution load in the area. Significant negative correlation between ambient SO2 concentration and species diversity suggested selective elimination of sensitive species from the heavily polluted sites.

  1. Poisonous plants: effects on embryo and fetal development.

    PubMed

    Panter, Kip E; Welch, Kevin D; Gardner, Dale R; Green, Benedict T

    2013-12-01

    Poisonous plant research in the United States began over 100 years ago as a result of livestock losses from toxic plants as settlers migrated westward with their flocks, herds, and families. Major losses were soon associated with poisonous plants, such as locoweeds, selenium accumulating plants, poison-hemlock, larkspurs, Veratrum, lupines, death camas, water hemlock, and others. Identification of plants associated with poisoning, chemistry of the plants, physiological effects, pathology, diagnosis, and prognosis, why animals eat the plants, and grazing management to mitigate losses became the overarching mission of the current Poisonous Plant Research Laboratory. Additionally, spin-off benefits resulting from the animal research have provided novel compounds, new techniques, and animal models to study human health conditions (biomedical research). The Poisonous Plant Research Laboratory has become an international leader of poisonous plant research as evidenced by the recent completion of the ninth International Symposium on Poisonous Plant Research held July 2013 in Hohhot, Inner Mongolia, China. In this article, we review plants that negatively impact embryo/fetal and neonatal growth and development, with emphasis on those plants that cause birth defects. Although this article focuses on the general aspects of selected groups of plants and their effects on the developing offspring, a companion paper in this volume reviews current understanding of the physiological, biochemical, and molecular mechanisms of toxicoses and teratogenesis.

  2. [Selection of winter plant species for wetlands constructed as sewage treatment systems and evaluation of their wastewater purification potentials].

    PubMed

    Chen, Yong-hua; Wu, Xiao-fu; Chen, Ming-li; Jiang, Li-juan; Li, Ke-lin; Lei, Dian; Wang, Hai-bin

    2010-08-01

    In order to establish an evaluation system for selection of winter wetland plants possessing high wastewater purification potentials in subtropics areas, designed sewage treatment experiments were carried out by introducing into the constructed wetlands 25 species of winter wetland plants. Cluster analysis was performed by including harmful environment-resistant enzyme and substrate enzyme activities into the commonly applied plant screening and assessment indexes system. The obtained results indicated that there were significant differences among the tested winter plants in their root length and vigor, leaf malonaldehyde (MDA), biomass, average nitrogen and phosphorus concentration and uptake, and urease and phosphoric acid enzyme activities in the root areas. Based on the established evaluation system, the tested plants were clustered into 3 groups. The plants in the 1st group possessing high purification potentials are Oenanthe javanica, Brassicacapestris, Juncus effusu, Saxifragaceae, Iris pseudoacorus, Osmanthus fragrans and Iris ensata; those in the 2nd group possessing moderate purification potentials are Brassica oleracea var acephala, Calendula officinalis, Aucuba japonica, Ligustrum lucidu, Beta vulgaris, Rhododendron simsii and Ilex latifolia; and those in the 3rd group with low purification potentials are Brassica oleracea var acephala, Calistephus chinensis, Rosa chinensis, Antirrhinums, Liriope palatyphylla, Zephyranthes candida, Fatshedera lizei, Petunia hybrida, Ilex quihoui, Dianthus caryophyllus and Loropetalum chinensis.

  3. [Selection of winter plant species for wetlands constructed as sewage treatment systems and evaluation of their wastewater purification potentials].

    PubMed

    Chen, Yong-hua; Wu, Xiao-fu; Chen, Ming-li; Jiang, Li-juan; Li, Ke-lin; Lei, Dian; Wang, Hai-bin

    2010-08-01

    In order to establish an evaluation system for selection of winter wetland plants possessing high wastewater purification potentials in subtropics areas, designed sewage treatment experiments were carried out by introducing into the constructed wetlands 25 species of winter wetland plants. Cluster analysis was performed by including harmful environment-resistant enzyme and substrate enzyme activities into the commonly applied plant screening and assessment indexes system. The obtained results indicated that there were significant differences among the tested winter plants in their root length and vigor, leaf malonaldehyde (MDA), biomass, average nitrogen and phosphorus concentration and uptake, and urease and phosphoric acid enzyme activities in the root areas. Based on the established evaluation system, the tested plants were clustered into 3 groups. The plants in the 1st group possessing high purification potentials are Oenanthe javanica, Brassicacapestris, Juncus effusu, Saxifragaceae, Iris pseudoacorus, Osmanthus fragrans and Iris ensata; those in the 2nd group possessing moderate purification potentials are Brassica oleracea var acephala, Calendula officinalis, Aucuba japonica, Ligustrum lucidu, Beta vulgaris, Rhododendron simsii and Ilex latifolia; and those in the 3rd group with low purification potentials are Brassica oleracea var acephala, Calistephus chinensis, Rosa chinensis, Antirrhinums, Liriope palatyphylla, Zephyranthes candida, Fatshedera lizei, Petunia hybrida, Ilex quihoui, Dianthus caryophyllus and Loropetalum chinensis. PMID:21090294

  4. [Selection and purification potential evaluation of woody plant in vertical flow constructed wetlands in the subtropical area].

    PubMed

    Chen, Yong-Hua; Wu, Xiao-Fu; Hao, Jun; Chen, Ming-Li; Zhu, Guang-Yu

    2014-02-01

    In order to solve the problem that wetland herbaceous plants tend to die during winter in subtropics areas, selection and purification potential evaluation experiments were carried out by introducing into the constructed wetlands 16 species of woody wetland plants. Cluster analysis was performed by including the morphological characteristics, physiological characteristics, as well as nitrogen and phosphorus accumulation of the woody wetland plants. The results indicated that there were significant differences among the tested woody plants in their survival rate, height increase, root length increase and vigor, Chlorophyll content, Superoxide dismutase, Malonaldehyde, Proline, Peroxidase, biomass, average concentration and accumulation of nitrogen and phosphorus. Based on the established evaluation system, the tested plants were clustered into 3 groups. The plants in the 1st group possessing high purification potentials are Nerium oleander and Hibiscus syriacus. Those in the 2nd group possessing moderate purification potentials are Trachycarpus fortune, Llex latifolia Thunb., Gardenia jasminoides, Serissa foetida and Ilex crenatacv Convexa. And those in the 3rd group with low purification potentials are Jasminum udiflorum, Hedera helix, Ligustrum vicaryi, Ligustrum lucidum, Buxus sempervives, Murraya paniculata, Osmanthus fragrans, Mahoniafortune and Photinia serrulata. PMID:24812951

  5. Are Animals "More Alive" than Plants? Animistic-Anthropocentric Construction of Life Concept

    ERIC Educational Resources Information Center

    Yorek, Nurettin; Sahin, Mehmet; Aydin, Halil

    2009-01-01

    This study investigated the characteristics students use in attributing value to and classifying the living things; the relational construction of the life concepts and the living things and the place of human in this construction. Participants were first-year high school students from seven schools in Izmir (a large western city in Turkey). An…

  6. Secondary succession of arthropods and plants in the Arizona Sonoran Desert in response to transmission line construction

    SciTech Connect

    Johnson, C.D.; Beley, J.R.; Ditsworth, T.M.; Butt, S.M.

    1983-03-01

    At a site about 16 km south of Black Canyon City, Arizona, density of arthropods on an undisturbed plot after an access road was built for powerline construction was much greater than on a disturbed plot. Mites, springtails, leafhoppers, scale insects, ants and thrips were signficantly reduced on the disturbed area. Our results indicate that restoration of numbers of arthropods on the disturbed area is dependent on the total plant cover on the plot, apparently regardless of the composition of the plant species involved. It is obvious in this area that the plant communities will remain dissimilar, with the pioneering herbaceous plants on the disturbed plot dominating. Cosntruction of a powerline apparently has had little impact on the structure of the arthropod community on the disturbed area, as proportions of three trophic categories of arthropods have not been radically altered. The results of this study, when compared to other studies in the Sonoran Desert and in desert grasslands disturbed by powerline construction, indicate that lengthy secondary succession does occur in the Sonoran Desert. Early arthropod invaders were found to be mainly herbivores, with few parasites or predators, and an equilibrium was eventually reached between colonizers and space requirements.

  7. Construction and start-up of a 250 kW natural gas fueled MCFC demonstration power plant

    SciTech Connect

    Figueroa, R.A.; Carter, J.; Rivera, R.; Otahal, J.

    1996-12-31

    San Diego Gas & Electric (SDG&E) is participating with M-C Power in the development and commercialization program of their internally manifolded heat exchanger (IMHEX{reg_sign}) carbonate fuel cell technology. Development of the IMHEX technology base on the UNOCAL test facility resulted in the demonstration of a 250 kW thermally integrated power plant located at the Naval Air Station at Miramar, California. The members of the commercialization team lead by M-C Power (MCP) include Bechtel Corporation, Stewart & Stevenson Services, Inc., and Ishikawajima-Harima Heavy Industries (IHI). MCP produced the fuel cell stack, Bechtel was responsible for the process engineering including the control system, Stewart & Stevenson was responsible for packaging the process equipment in a skid (pumps, desulfurizer, gas heater, turbo, heat exchanger and stem generator), IHI produced a compact flat plate catalytic reformer operating on natural gas, and SDG&E assumed responsibility for plant construction, start-up and operation of the plant.

  8. [EFFECTS OF DIFFERENT CLASSES OF PLANT HORMONES ON MAMMALIAN CELLS].

    PubMed

    Vildanova, M S; Smirnova, E A

    2016-01-01

    Plant hormones are signal molecules of different chemical structure, secreted by plant cells and acting at low concentrations as regulators of plant growth and differentiation. Certain plant hormones are similar to animal hormones or can be produced by animal cells. A number of studies show that the effect of biologically active components of plant origin including plant/phytohormones is much wider than was previously thought, but so far there are no objective criteria for assessing the influence of phytohormones on the physiological state of animal cells. Presented in the survey data show that plant hormones, which have different effects on plant growth and development (jasmonic, abscisic and gibberellic acids), are not neutral to the cells of animal origin, and animal cells response to them may be either positive or negative. PMID:27220246

  9. Magnetic field effects on plant growth, development, and evolution

    PubMed Central

    Maffei, Massimo E.

    2014-01-01

    The geomagnetic field (GMF) is a natural component of our environment. Plants, which are known to sense different wavelengths of light, respond to gravity, react to touch and electrical signaling, cannot escape the effect of GMF. While phototropism, gravitropism, and tigmotropism have been thoroughly studied, the impact of GMF on plant growth and development is not well-understood. This review describes the effects of altering magnetic field (MF) conditions on plants by considering plant responses to MF values either lower or higher than those of the GMF. The possible role of GMF on plant evolution and the nature of the magnetoreceptor is also discussed. PMID:25237317

  10. Effects of the substrate depth on purification performance of a hybrid constructed wetland treating domestic sewage.

    PubMed

    Ren, Yong-Xiang; Zhang, Hai; Wang, Chao; Yang, Yong-Zhe; Qin, Zhen; Ma, Yun

    2011-01-01

    The depth of substrate in constructed wetlands (CWs) has a significant effect on the construction investment and the purification performance of CWs. In this study, a pilot scale CW system was operated in a domestic sewage treatment plant in Xi'an, China. The experimental systems included three-series CWs systems with substrate depths of 0.1m, 0.3 m and 0.6 m, respectively. Each series was composed of a hydroponic ditch, a horizontal subsurface flow CW and a vertical flow CW. The effluent from the primary clarifier in the sewage treatment plant was intermittently conducted to the wetlands at a flow rate of 0.3 m(3)/d. The hydraulic loading rate of each CWs system was regulated at 0.1 m(3)/m(2).d and the hydraulic retention time was 3 days. Canna indica L. was planted both in the hydroponic ditches and the CWs systems. Results showed that the highest removal efficiency of NH(+)(4)-N and TP was obtained in the hybrid CW with 0.1 m substrate depth. The average removal efficiency for NH(+)(4)-N and TP were 90.6 % and 80.0 %, respectively. The highest average removal efficiency of COD was obtained in hybrid CWs system with 0.6 m substrate depth. Therefore, a simultaneous removal of COD and nutrients can be achieved through the combination of different wetlands using different substrate depths. In addition, the substrate depth presents significant effects on the concentration of DO and root growth characteristics of canna in the system. As a result, the highest concentration of DO (>2 mg/L) and the highest amount of roots production were achieved in the 0.1 m substrate depth horizontal and vertical flow CWs.

  11. 57. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT GENERAL, DOUBLE EFFECT ...

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

    57. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT GENERAL, DOUBLE EFFECT EVAPORATOR UNIT - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  12. 56. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT GENERAL, DOUBLE EFFECT ...

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

    56. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT GENERAL, DOUBLE EFFECT EVAPORATOR UNIT - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  13. The effect of disturbance on an ant-plant mutualism.

    PubMed

    Piovia-Scott, Jonah

    2011-06-01

    Protective ant-plant mutualisms-where plants provide food or shelter to ants and ants protect the plants from herbivores-are a common feature in many ecological communities, but few studies have examined the effect of disturbance on these interactions. Disturbance may affect the relationship between plants and their associated ant mutualists by increasing the plants' susceptibility to herbivores, changing the amount of reward provided for the ants, and altering the abundance of ants and other predators. Pruning was used to simulate the damage to buttonwood mangrove (Conocarpus erectus) caused by hurricanes. Pruned plants grew faster than unpruned plants, produced lower levels of physical anti-herbivore defenses (trichomes, toughness), and higher levels of chemical defenses (tannins) and extrafloral nectaries. Thus, simulated hurricane damage increased plant growth and the amount of reward provided to ant mutualists, but did not have consistent effects on other anti-herbivore defenses. Both herbivores and ants increased in abundance on pruned plants, indicating that the effects of simulated hurricane damage on plant traits were propagated to higher trophic levels. Ant-exclusion led to higher leaf damage on both pruned and upruned plants. The effect of ant-exclusion did not differ between pruned and unpruned plants, despite the fact that pruned plants had higher ant and herbivore densities, produced more extrafloral nectaries, and had fewer physical defenses. Another common predator, clubionid spiders, increased in abundance on pruned plants from which ants had been excluded. I suggest that compensatory predation by these spiders diminished the effect of ant-exclusion on pruned plants.

  14. Case studies of unique problems and events encountered during design, construction, and operation of three large commercial-scale fuel ethanol plants

    SciTech Connect

    Jones, K.W.

    1984-01-01

    This paper summarizes the unique problems and events encountered during the design, construction, start-up, and operation phases of three differently constructed alcohol fuel projects. These projects were awarded cost sharing contracts (Cooperative Agreements) as part of the Department of Energy's effort to expedite ethanol production on a commercial scale. The scope of the projects included final design, economic and financial analysis, market analysis, environmental analysis, facility construction, and plant start-up operation. The three ethanol plants are a 20-million gallon per year (MMGPY) new-construction or grass roots facility; a 60-MMGPY plant constructed using refurbished equipment at a decommissioned ammonia fertilizer facility; and a 10-MMGPY retrofitted brewery. A comparison of the case histories of these projects clearly points out the advantages and disadvantages of each type of design and construction.

  15. Effect of processing plant on pork quality.

    PubMed

    Hambrecht, E; Eissen, J J; Verstegen, M W A

    2003-06-01

    The impact of processing plant on pork quality was studied by assessing pork quality in three commercial plants (A, B, C). Plants differed in the layout of the races, stunning systems (A and B: electrical, C: CO(2) stunning) and chilling systems (A: rapid chilling, B and C: conventional). Factors not related to the processing plants (e.g. genetic background of animals, transport, lairage) were standardized. In total, nine batches of about 150 pigs each were processed. Each batch was purchased at a commercial farm and randomly divided into three groups for delivery to the three processing plants. Meat quality was evaluated by measuring early post-mortem muscle pH and temperature as well as ultimate pH, meat colour (Minolta Chroma Meter and Japanese colour scale), filter paper score (FPS), electrical conductivity (EC) and drip loss. Plant C produced an inferior quality compared to plants A and B: meat was paler (C: 2.8 vs. A: 2.9 and B: 3.0 on the Japanese colour scale) and had higher drip losses (C: 5.2 vs. A: 4.8 and B: 4.9%). Meat colour hardly differed between plants A and B but waterholding properties were best at plant A as indicated by FPS (A: 2.4 vs. B: 2.8 vs. C: 3.3) and EC (A: 5.4 vs. B: 6.4 vs. C: 7.4 mS). It is concluded that processing plant may influence meat quality. Correlations between early post-mortem measurements and meat quality traits were low. Nevertheless, high carcass temperatures and low pH values early post-mortem were shown to lead to inferior meat quality.

  16. An investigation and analysis of safety issues in Polish small construction plants.

    PubMed

    Dąbrowski, Andrzej

    2015-01-01

    The construction industry is a booming sector of the Polish economy; however, it is stigmatised by a lower classification due to high occupational risks and an unsatisfactory state of occupational safety. Safety on construction sites is compromised by small construction firms which dominate the market and have high accident rates. This article presents the results of studies (using a checklist) conducted in small Polish construction companies in terms of selected aspects of safety, such as co-operation with the general contractor, occupational health and safety documents, occupational risk assessment, organization of work, protective gear and general work equipment. The mentioned studies and analyses provided the grounds to establish the main directions of preventive measures decreasing occupational risk in small construction companies, e.g., an increase in engagement of investors and general contractors, improvement of occupational health and safety (OSH) documents, an increase in efficiency of construction site managers, better stability of employment and removal of opposing objectives between economic strategy and work safety. PMID:26694002

  17. An investigation and analysis of safety issues in Polish small construction plants

    PubMed Central

    Dąbrowski, Andrzej

    2015-01-01

    The construction industry is a booming sector of the Polish economy; however, it is stigmatised by a lower classification due to high occupational risks and an unsatisfactory state of occupational safety. Safety on construction sites is compromised by small construction firms which dominate the market and have high accident rates. This article presents the results of studies (using a checklist) conducted in small Polish construction companies in terms of selected aspects of safety, such as co-operation with the general contractor, occupational health and safety documents, occupational risk assessment, organization of work, protective gear and general work equipment. The mentioned studies and analyses provided the grounds to establish the main directions of preventive measures decreasing occupational risk in small construction companies, e.g., an increase in engagement of investors and general contractors, improvement of occupational health and safety (OSH) documents, an increase in efficiency of construction site managers, better stability of employment and removal of opposing objectives between economic strategy and work safety. PMID:26694002

  18. An investigation and analysis of safety issues in Polish small construction plants.

    PubMed

    Dąbrowski, Andrzej

    2015-01-01

    The construction industry is a booming sector of the Polish economy; however, it is stigmatised by a lower classification due to high occupational risks and an unsatisfactory state of occupational safety. Safety on construction sites is compromised by small construction firms which dominate the market and have high accident rates. This article presents the results of studies (using a checklist) conducted in small Polish construction companies in terms of selected aspects of safety, such as co-operation with the general contractor, occupational health and safety documents, occupational risk assessment, organization of work, protective gear and general work equipment. The mentioned studies and analyses provided the grounds to establish the main directions of preventive measures decreasing occupational risk in small construction companies, e.g., an increase in engagement of investors and general contractors, improvement of occupational health and safety (OSH) documents, an increase in efficiency of construction site managers, better stability of employment and removal of opposing objectives between economic strategy and work safety.

  19. Retention and mitigation of metals in sediment, soil, water, and plant of a newly constructed root-channel wetland (China) from slightly polluted source water.

    PubMed

    Wang, Baoling; Wang, Yu; Wang, Weidong

    2014-01-01

    Constructed root-channel wetland (CRCW) is a term for pre-pond/wetland/post-pond complexes, where the wetland includes plant-bed/ditch landscape and root-channel structure. Source water out of pre-ponds flows through alternate small ditches and plant beds with root-channels via a big ditch under hydraulic regulation. Then source water flows into post-ponds to finish final polishing. This article aims to explore the potential of components of a pilot CRCW in China on mitigating metals in micro-polluted source water during its initial operation stage. We investigated six heavy metals (Cd, Cr, Cu, Ni, Zn, and Pb) in surface sediment, plant-bed subsurface soil, water, and aquatic plants during 2012-2013. Monitoring results showed that pond/ditch sediments and plant-bed soil retained a significant amount of Cr, Ni, and Zn with 93.1%, 72.4%, and 57.5% samples showing contamination factor above limit 1 respectively. Remarkably the high values of metal enrichment factor (EF) occurred in root-channel zones. Water monitoring results indicated that Ni, Zn, and Pb were removed by 78.5% (66.7%), 57.6% (59.6%), and 26.0% (7.5%) in east (west) wetland respectively. Mass balance estimation revealed that heavy metal mass in the pond/ditch sediments accounted for 63.30% and that in plant-bed soil 36.67%, while plant uptake occupied only 0.03%. The heavy metal accretion flux in sediments was 0.41 - 211.08 μg · cm(-2) · a(-1), less than that in plant-bed soil (0.73 - 543.94 μg · cm(-2) · a(-1)). The 1.83 ha wetland has retained about 86.18 kg total heavy metals within 494 days after operation. This pilot case study proves that constructed root-channel wetland can reduce the potential ecological risk of purified raw water and provide a new and effective method for the removal of heavy metals from drinking water sources. PMID:25032090

  20. Plant-mediated 'apparent effects' between mycorrhiza and insect herbivores.

    PubMed

    Gilbert, Lucy; Johnson, David

    2015-08-01

    Plants mediate indirect 'apparent' effects between above-ground herbivores and below-ground mutualistic mycorrhizal fungi. The herbivore-plant-mycorrhiza continuum is further complicated because signals produced by plants in response to herbivores can be transmitted to other plants via shared fungal networks below ground. Insect herbivores, such as aphids, probably affect the functioning of mycorrhizal fungi by changing the supply of recent photosynthate from plants to mycorrhizas, whereas there is evidence that mycorrhizas affect aphid fitness by changing plant signalling pathways, rather than only through improved nutrition. New knowledge of the transfer of signals through fungal networks between plant species means we now need a better understanding of how this process occurs in relation to the feeding preferences of herbivores to shape plant community composition and herbivore behaviour in nature.

  1. Responses of a constructed plant community to simulated glyphosate and dicamba drift

    EPA Science Inventory

    Background/Questions/Methods As part of its regulation of pesticides, the US Environmental Protection Agency must consider environmental risks, including impacts to nontarget plants exposed to pesticide drift. Normally these risk assessments consider impacts to individual spec...

  2. GENE FLOW STUDIES BETWEEN BRASSICA NAPUS AND B. RAPA IN CONSTRUCTED PLANT COMMUNITIES

    EPA Science Inventory

    The commercial production of genetically modified crops has led to a growing awareness of the difficulties of transgene confinement and of the potential environmental risks associated with the escape of transgenes into naturalized or native plant populations. A potential conseque...

  3. Responses of a constructed plant community to combinations of herbicides, a model for field tests?

    EPA Science Inventory

    As part of its regulation of pesticides, the US Environmental Protection Agency considers environmental risks, including impacts to nontarget plants exposed to pesticide drift. Normally these risk assessments consider impacts to individual species, using greenhouse, exposure-res...

  4. Accelerating plant DNA barcode reference library construction using herbarium specimens: improved experimental techniques.

    PubMed

    Xu, Chao; Dong, Wenpan; Shi, Shuo; Cheng, Tao; Li, Changhao; Liu, Yanlei; Wu, Ping; Wu, Hongkun; Gao, Peng; Zhou, Shiliang

    2015-11-01

    A well-covered reference library is crucial for successful identification of species by DNA barcoding. The biggest difficulty in building such a reference library is the lack of materials of organisms. Herbarium collections are potentially an enormous resource of materials. In this study, we demonstrate that it is likely to build such reference libraries using the reconstructed (self-primed PCR amplified) DNA from the herbarium specimens. We used 179 rosaceous specimens to test the effects of DNA reconstruction, 420 randomly sampled specimens to estimate the usable percentage and another 223 specimens of true cherries (Cerasus, Rosaceae) to test the coverage of usable specimens to the species. The barcode rbcLb (the central four-sevenths of rbcL gene) and matK was each amplified in two halves and sequenced on Roche GS 454 FLX+. DNA from the herbarium specimens was typically shorter than 300 bp. DNA reconstruction enabled amplification fragments of 400-500 bp without bringing or inducing any sequence errors. About one-third of specimens in the national herbarium of China (PE) were proven usable after DNA reconstruction. The specimens in PE cover all Chinese true cherry species and 91.5% of vascular species listed in Flora of China. It is very possible to build well-covered reference libraries for DNA barcoding of vascular species in China. As exemplified in this study, DNA reconstruction and DNA-labelled next-generation sequencing can accelerate the construction of local reference libraries. By putting the local reference libraries together, a global library for DNA barcoding becomes closer to reality.

  5. RNAi and viral vectors as useful tools in the functional genomics of plants. Construction of BMV-based vectors for RNA delivery into plant cells.

    PubMed

    Wojtkowiak, Agnieszka; Siek, Anna; Alejska, Magdalena; Jarmołowski, Artur; Szweykowska-Kulińska, Zofia; Figlerowicz, Marek

    2002-01-01

    The sequencing of several complete genomes and the development of a DNA microarray technology are among the most important achievements of molecular biology. They gave the proper grounds for the development of modern functional genomics. However, there is one additional condition which needs to be satisfied to truely enable the study of how a genome works: a suitable method of selectively inducing and silencing the expression of each individual gene. The methods used so far have usually only permitted the influencing of gene expression through genetic manipulations at the DNA level (genetically modified plants). The discovery of RNA interference (RNAi) opens up completely new possibilities of research on the functioning of particular plant genes, without the necessity of altering the genome structure. In this case, interference takes place at the transcript level. Thus, at any given moment during plant development, the expression of a specific gene (or several genes) can be inhibited, even if it is important for the survival of the organism under study. To this end, a double-stranded RNA inducing the RNAi phenomenon has to be delivered into the plant cell. Here we describe the construction of four brome mosaic virus-based vectors, which, as our preliminary data indicate, can be used to transfer RNA into barley cells.

  6. Monitoring of the effect of biological activity on the pedogenesis of a constructed Technosol

    NASA Astrophysics Data System (ADS)

    Salifou Jangorzo, Nouhou; Watteau, Françoise; Schwartz, Christophe

    2014-05-01

    Pedogenesis is the set of steps, which lead to the formation and evolution of soils under pedogenetic factors and processes. They may be described quantitatively for a modeling end. For this purpose, constructed Technosols are candidates to be studied, because their initial composition is well described. Furthermore, among pedogenetic factors, living organisms are known to play a major role in soil formation. The most challenging objective of our work is then to monitor in situ the effect of biological agents on soil evolution. However, soil pedogenesis is known to be dynamic, therefore visualizing in situ plant roots or soil fauna in contact with soil, will help understand better how pedogenesis occurs realistically. The aim of this work is to study in situ, visually and quantitatively, the evolution of a constructed Technosol pedogenesis using an innovative dispositive of observation on cosmes. The Technosol is constructed in three horizons, from bottom to top we have: gravels, treated industrial soil and paper mill sludge (2/3, 1/3 masse ratio) and green waste compost. The soil is put into a cosme equipped with image acquisition devices. Factors are organized into two modalities each repeated three times. "Plant", where five seeds of white lupin are sown in each cosme. "Plant and Fauna" where six epigeic adult earthworms and five seeds of white lupin are inoculated, and a "control". A moisture of 60 - 80 % field capacity is maintained in all modalities. Results show that roots grow at 10 mm.day-1 speed during the first three weeks. Roots increase porosity and aggregation with time. Earthworms explore the soil randomly by creating and filling burrows. At a second time, they create their burrows preferentially along plant roots. Roots and earthworms contribute to the rapid increase of porosity (9.81 times control at 268 days) and aggregation (10.15 times control at 268 days) during time, in the early stages of pedogenesis. In situ and non-destructive observation

  7. Developing a Planting Medium from Solid Waste Compost and Construction and Demolition Rubble for Use in Quarry Rehabilitation

    NASA Astrophysics Data System (ADS)

    Assaf, E. A.

    2015-12-01

    The combination of construction, demolition and excavation (CDE) waste along with the increase in solid waste generation has put a major stress on Lebanon and on the management of its solid waste. Compounding this problem are the issues of quarries closure and rehabilitation and a decrease in forest and vegetative cover. This research aims to provide an integrated solution to the stated problem by developing a "soil mix" derived from a mélange of the organic matter of the solid waste (compost), the CDE waste, and soil. Excavation and construction debris were ground to several sizes and mixed with compost and soil at different ratios. Replicates of these mixes and a set of control (regular soil) were used. In this mix, native and indicator plants are planted (in pots). The plant species used are Mathiolla crassifolia and Zea mays (Corn). Results have shown successful growth of both corn and Mathiolla seedlings in the mixes with higher amounts of construction rubble and compost i.e. Rubble: Soil: Compost Ratio of 2:1:1 and 1:0:1. However treatments with no compost and with less quantities of rubble demonstrated the inability of the soil used to sustain plant growth alone (1:1:1 and 1:1:0). Last but not least, the control consisting of soil only ended up being the weakest mix with yellow corn leaves and small Mathiolla seedlings fifty days after planting and fertilizing. Additionally, soil analysis, rubble and compost analysis were conducted. The samples were tested for heavy metals, nutrient availability and values of pH and EC. No contamination has been reported and an abundance of macronutrients and micronutrients was documented for the soil and compost. High alkalinity is due to the presence of concrete and the high percentage of Calcium Carbonate in Lebanese soils. Accordingly, the most adequate mixes for planting are treatments A (2:1:1) and B (1:0:1) and they should be pursued for a pilot scale study to test their potential use in quarry rehabilitation and

  8. Effect of pre-planting irrigation, maize planting pattern and nitrogen on weed seed bank population.

    PubMed

    Hemmati, E; Vazan, S; Oveisi, M

    2011-01-01

    Pre-planting irrigation and planting patterns are important factors in weed management that effect on seed bank. Additionally, the nitrogen is the most important factor in plant growth that affects weed-crop competition and ultimately, seed rain into the soil. A field experiment was conducted to study the effect of nitrogen application rates, pre-planting irrigation and maize planting patterns on weed seed bank population. Experimental factors were nitrogen rates at 4 levels (200, 300, 400 and 500 kg per hectare) as main plot; and pre-planting irrigation at 2 levels (irrigation before planting plus weeding emerged seedlings and, irrigation after sowing), and maize planting patterns (one-row and two-row planting of maize with same density per square of row length) that were assigned in a factorial arrangement to the sub plots. Soil samples were taken at the beginning of the season (before planting of maize) and at the end of the season (after harvest) at depth of 0-5 cm in the fixed quadrates (60 cm x 60 cm). The weed seeds were extracted from the soil samples and were identified using standard methods. The majority of weed seed bank populations included 6 weed species: Portulaca oleracea, Chenopodium album, Amaranthus retroflexus, Sorghum halepense, Daturea stramonium, Xanthium strumarium. Results showed that population of weed seed bank increased significantly with increasing nitrogen rate. The increasing rate was different between one-row and two-row planting patterns. The parameters indicated that seed bank population was much higher in a one row planting pattern of maize. With two-row planting, seed bank was decreased by 34, 26, 20 and 5% at 200, 300, 400 and 500 kg N/ha, respectively. Pre-planting irrigation was also found an effective implement to reduce the weed seed bank. When pre-planting irrigation was applied, seed bank was decreased by 57, 43, 34 and 9% at 200, 300, 400 and 500 kg N/ha. Increasing nitrogen because of weed's better growth and higher seed

  9. Effect of pre-planting irrigation, maize planting pattern and nitrogen on weed seed bank population.

    PubMed

    Hemmati, E; Vazan, S; Oveisi, M

    2011-01-01

    Pre-planting irrigation and planting patterns are important factors in weed management that effect on seed bank. Additionally, the nitrogen is the most important factor in plant growth that affects weed-crop competition and ultimately, seed rain into the soil. A field experiment was conducted to study the effect of nitrogen application rates, pre-planting irrigation and maize planting patterns on weed seed bank population. Experimental factors were nitrogen rates at 4 levels (200, 300, 400 and 500 kg per hectare) as main plot; and pre-planting irrigation at 2 levels (irrigation before planting plus weeding emerged seedlings and, irrigation after sowing), and maize planting patterns (one-row and two-row planting of maize with same density per square of row length) that were assigned in a factorial arrangement to the sub plots. Soil samples were taken at the beginning of the season (before planting of maize) and at the end of the season (after harvest) at depth of 0-5 cm in the fixed quadrates (60 cm x 60 cm). The weed seeds were extracted from the soil samples and were identified using standard methods. The majority of weed seed bank populations included 6 weed species: Portulaca oleracea, Chenopodium album, Amaranthus retroflexus, Sorghum halepense, Daturea stramonium, Xanthium strumarium. Results showed that population of weed seed bank increased significantly with increasing nitrogen rate. The increasing rate was different between one-row and two-row planting patterns. The parameters indicated that seed bank population was much higher in a one row planting pattern of maize. With two-row planting, seed bank was decreased by 34, 26, 20 and 5% at 200, 300, 400 and 500 kg N/ha, respectively. Pre-planting irrigation was also found an effective implement to reduce the weed seed bank. When pre-planting irrigation was applied, seed bank was decreased by 57, 43, 34 and 9% at 200, 300, 400 and 500 kg N/ha. Increasing nitrogen because of weed's better growth and higher seed

  10. Oxygen effects on photosynthesis and C metabolism in desert plants.

    PubMed

    Glacoleva, T A; Zalensky, O V

    1978-08-01

    The effect of 1% and 21% O(2) upon (14)CO(2) assimilation by desert plants exposed for 10 to 90 seconds has been studied. The plants studied can be divided into three groups with respect to O(2). The C(3) plants display the usual Warburg effect. No changes could be observed in the intensity of photosynthesis as a function of O(2) content in another group of plants (showing signs of Crassulacean acid metabolism). In still another group of plants (C(4) plants) the stimulating effect of O(2) on photosynthesis could be detected. In C(3) plants, O(2) inhibits the processing of carbon through the Calvin cycle intermediates. The involvement of carbon in the glycolate pathway fails to explain completely the inhibiting effect of O(2) on photosynthesis. It is assumed that O(2) inhibits the enzymes of the Calvin cycle. In C(4) plants O(2) stimulates the incorporation of (14)C into malate and aspartate. The incorporation of (14)C into the intermediates of the Calvin cycle in C(4) plants is inhibited much like that in typical C(3) plants.

  11. Characterisation of Liquefaction Effects for Beyond-Design Basis Safety Assessment of Nuclear Power Plants

    NASA Astrophysics Data System (ADS)

    Bán, Zoltán; Győri, Erzsébet; János Katona, Tamás; Tóth, László

    2015-04-01

    Preparedness of nuclear power plants to beyond design base external effects became high importance after 11th of March 2011 Great Tohoku Earthquakes. In case of some nuclear power plants constructed at the soft soil sites, liquefaction should be considered as a beyond design basis hazard. The consequences of liquefaction have to be analysed with the aim of definition of post-event plant condition, identification of plant vulnerabilities and planning the necessary measures for accident management. In the paper, the methodology of the analysis of liquefaction effects for nuclear power plants is outlined. The case of Nuclear Power Plant at Paks, Hungary is used as an example for demonstration of practical importance of the presented results and considerations. Contrary to the design, conservatism of the methodology for the evaluation of beyond design basis liquefaction effects for an operating plant has to be limited to a reasonable level. Consequently, applicability of all existing methods has to be considered for the best estimation. The adequacy and conclusiveness of the results is mainly limited by the epistemic uncertainty of the methods used for liquefaction hazard definition and definition of engineering parameters characterizing the consequences of liquefaction. The methods have to comply with controversial requirements. They have to be consistent and widely accepted and used in the practice. They have to be based on the comprehensive database. They have to provide basis for the evaluation of dominating engineering parameters that control the post-liquefaction response of the plant structures. Experience of Kashiwazaki-Kariwa plant hit by Niigata-ken Chuetsu-oki earthquake of 16 July 2007 and analysis of site conditions and plant layout at Paks plant have shown that the differential settlement is found to be the dominating effect in case considered. They have to be based on the probabilistic seismic hazard assessment and allow the integration into logic

  12. Construction of a Der p2-transgenic plant for the alleviation of airway inflammation.

    PubMed

    Lee, C C; Ho, H; Lee, K T; Jeng, S T; Chiang, B L

    2011-09-01

    In clinical therapy, the amount of antigen administered to achieve oral tolerance for allergic diseases is large, and the cost is a major consideration. In this study, we used tobacco plants to develop a large-scale protein production system for allergen-specific immunotherapy, and we investigated the mechanisms of oral tolerance induced by a transgenic plant-derived antigen. We used plants (tobacco leaves) transgenic for the Dermatophagoides pteronyssinus 2 (Der p2) antigen to produce Der p2. Mice received total protein extract from Der p2 orally once per day over 6 days (days 0-2 and days 6-8). Mice were also sensitized and challenged with yeast-derived recombinant Der p2 (rDer p2), after which the mice were examined for airway hyper-responsiveness and airway inflammation. After sensitization and challenge with rDer p2, mice that were fed with total protein extracted from transgenic plants showed decreases in serum Der p2-specific IgE and IgG1 titers, decreased IL-5 and eotaxin levels in bronchial alveolar lavage fluid, and eosinophil infiltration in the airway. In addition, hyper-responsiveness was also decreased in mice that were fed with total protein extracted from transgenic plants, and CD4(+)CD25(+)Foxp3(+) regulatory T cells were significantly increased in mediastinal and mesenteric lymph nodes. Furthermore, splenocytes isolated from transgenic plant protein-fed mice exhibited decreased proliferation and increased IL-10 secretion after stimulation with rDer p2. The data here suggest that allergen-expressing transgenic plants could be used for therapeutic purposes for allergic diseases.

  13. Costs and water quality effects of wastewater treatment plant centralization

    SciTech Connect

    Macal, C.M.; Broomfield, B.J.

    1980-01-01

    The costs and water quality impacts of two regional configurations of municipal wastewater treatment plants in Northeastern Illinois are compared. In one configuration, several small treatment plants are consolidated into a smaller number of regional facilities. In the other, the smaller plants continue to operate. Costs for modifying the plants to obtain various levels of pollutant removal are estimated using a simulation model that considers the type of equipment existing at the plants and the costs of modifying that equipment to obtain a range of effluent levels for various pollutants. A dynamic water-quality/hydrology simulation model is used to determine the water quality effects of the various treatment technologies and pollutant levels. Cost and water quality data are combined and the cost-effectiveness of the two treatment configurations is compared. The regionalized treatment-plant configuration is found to be the more cost-effective.

  14. BSM2 Plant-Wide Model construction and comparative analysis with other methodologies for integrated modelling.

    PubMed

    Grau, P; Vanrolleghem, P; Ayesa, E

    2007-01-01

    In this paper, a new methodology for integrated modelling of the WWTP has been used for the construction of the Benchmark Simulation Model N degrees 2 (BSM2). The transformations-approach proposed in this methodology does not require the development of specific transformers to interface unit process models and allows the construction of tailored models for a particular WWTP guaranteeing the mass and charge continuity for the whole model. The BSM2 PWM constructed as case study, is evaluated by means of simulations under different scenarios and its validity in reproducing water and sludge lines in WWTP is demonstrated. Furthermore the advantages that this methodology presents compared to other approaches for integrated modelling are verified in terms of flexibility and coherence. PMID:17978433

  15. Wetland Water Cooling Partnership: The Use of Constructed Wetlands to Enhance Thermoelectric Power Plant Cooling and Mitigate the Demand of Surface Water Use

    SciTech Connect

    Apfelbaum, Steven; Duvall, Kenneth; Nelson, Theresa; Mensing, Douglas; Bengtson, Harlan; Eppich, John; Penhallegon, Clayton; Thompson, Ry

    2013-09-30

    Through the Phase I study segment of contract #DE-NT0006644 with the U.S. Department of Energy’s National Energy Technology Laboratory, Applied Ecological Services, Inc. and Sterling Energy Services, LLC (the AES/SES Team) explored the use of constructed wetlands to help address stresses on surface water and groundwater resources from thermoelectric power plant cooling and makeup water requirements. The project objectives were crafted to explore and develop implementable water conservation and cooling strategies using constructed wetlands (not existing, naturally occurring wetlands), with the goal of determining if this strategy has the potential to reduce surface water and groundwater withdrawals of thermoelectric power plants throughout the country. Our team’s exploratory work has documented what appears to be a significant and practical potential for augmenting power plant cooling water resources for makeup supply at many, but not all, thermoelectric power plant sites. The intent is to help alleviate stress on existing surface water and groundwater resources through harvesting, storing, polishing and beneficially re-using critical water resources. Through literature review, development of conceptual created wetland plans, and STELLA-based modeling, the AES/SES team has developed heat and water balances for conventional thermoelectric power plants to evaluate wetland size requirements, water use, and comparative cooling technology costs. The ecological literature on organism tolerances to heated waters was used to understand the range of ecological outcomes achievable in created wetlands. This study suggests that wetlands and water harvesting can provide a practical and cost-effective strategy to augment cooling waters for thermoelectric power plants in many geographic settings of the United States, particularly east of the 100th meridian, and in coastal and riverine locations. The study concluded that constructed wetlands can have significant positive

  16. Construction and comparison of gene co-expression networks shows complex plant immune responses

    PubMed Central

    López, Camilo; López-Kleine, Liliana

    2014-01-01

    Gene co-expression networks (GCNs) are graphic representations that depict the coordinated transcription of genes in response to certain stimuli. GCNs provide functional annotations of genes whose function is unknown and are further used in studies of translational functional genomics among species. In this work, a methodology for the reconstruction and comparison of GCNs is presented. This approach was applied using gene expression data that were obtained from immunity experiments in Arabidopsis thaliana, rice, soybean, tomato and cassava. After the evaluation of diverse similarity metrics for the GCN reconstruction, we recommended the mutual information coefficient measurement and a clustering coefficient-based method for similarity threshold selection. To compare GCNs, we proposed a multivariate approach based on the Principal Component Analysis (PCA). Branches of plant immunity that were exemplified by each experiment were analyzed in conjunction with the PCA results, suggesting both the robustness and the dynamic nature of the cellular responses. The dynamic of molecular plant responses produced networks with different characteristics that are differentiable using our methodology. The comparison of GCNs from plant pathosystems, showed that in response to similar pathogens plants could activate conserved signaling pathways. The results confirmed that the closeness of GCNs projected on the principal component space is an indicative of similarity among GCNs. This also can be used to understand global patterns of events triggered during plant immune responses. PMID:25320678

  17. [Emission of microorganisms from sewage treatment plants depending upon construction differences of single structural parts].

    PubMed

    Eikmann, T; Schröder, S; Pieler, J; Bahr, H; Einbrodt, H J

    1986-04-01

    In order to examine the influence exerted by the differing design of individual water treatment plant units on the emission rate of micro-organisms and the associated degree of exposure to which plant personnel is subjected, measurements were taken at three different types of treatment plants. Measurements were made using "Biotest" RCS Air Samplers. The total count of colonies was determined by means of Agar Strips GK-A (tryptic soy agar). Enterobacteriaceae were quantitatively ascertained using Agar Strips C (MacConkey agar), particular attention being paid to the determination of the coliform bacteria as faeces indicators. Agar Strips S (mannitol salt agar) were used to measure the count of staphylococci using Agar Strips HS (rosa Bengal streptomycin agar). Before taking measurements, the prevailing climatic conditions were recorded. It could be ascertained that the enclosure of the inflow area (screw conveyor pump station and aerated grit removal tank) lead to a considerable increase in the concentration of microorganisms in the air within the housing. The values dropped however, when adequate ventilation was provided. Differing oxygen in the activated sludge tanks - finebubble aeration at the tank bottom or the blowing in of air via centrifugal blowers - lead to large variations in the emission rates. However, the less the waste water is agitated, the lower the emission rates. In the case of fine-bubble aeration, rates which are also normally to be found in the "non-burdened" outside air were even recorded close to the aeration tank. In cases of centrifugal blower, the aeration tank should be covered with a shield. With this type of aeration the waste water is emitted radially towards the walls of the tank. The use of a sprinkler unit on an aeration tank equipped with centrifugal blower - to avoid foam formation on the surface of the water - does not lead to an increase in the already high emission rate. An increase in air pollution through mould fungi from

  18. 21 CFR 111.20 - What design and construction requirements apply to your physical plant?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) The design and construction must include: (i) Floors, walls, and ceilings that can be adequately... bulbs, fixtures, skylights, or other glass or glass-like materials when the light bulbs, fixtures, skylights or other glass or glass-like materials are suspended over exposed components or...

  19. [Construction of high-effective symbiotic bacteria: evolutionary models and genetic approaches].

    PubMed

    Provorov, N A; Onishchuk, O P; Iurgel', S N; Kurchak, O N; Chizhevskaia, E P; Vorob'ev, N I; Zatovskaia, T V; Simarov, B V

    2014-11-01

    Using the example of N2-fixing legume-rhizobial symbiosis, we demonstrated that the origin and evolution of bacteria symbiotic for plants involve the following: 1) the formation of novel sym gene systems based on reorganizations of the bacterial genomes and on the gene transfer from the distant organisms; 2) the loss of genes encoding for functions that are required for autonomous performance but interfere with symbiotic functions (negative regulators of symbiosis). Therefore, the construction of effective rhizobia strains should involve improvement of sym genes activities (for instance, nif, fix, and dct genes, encoding for nitrogenase synthesis or for the energy supply of N2 fixation), as well as the inactivation of negative regulators of symbiosis identified in our lab (eff genes encoding for the transport of sugars, and the production of polysaccharides, and storage compounds, as well as for oxidative-reductive processes).

  20. Effect of plant species loss on aphid-parasitoid communities.

    PubMed

    Petermann, Jana S; Müller, Christine B; Weigelt, Alexandra; Weisser, Wolfgang W; Schmid, Bernhard

    2010-05-01

    1. The consequences of species loss on ecosystem functioning within a single trophic level have been extensively studied. However, the loss of basal species is likely to have profound impacts on the abundance, richness and ecosystem functioning of species at higher trophic levels. 2. Here, we used experimentally established plant communities with a species richness gradient to study the effects of plant species loss on a multi-trophic insect community in the field. We measured densities and species richness of aphids and parasitic wasps (primary, secondary and facultative tertiary parasitoids of aphids) that naturally colonized the grassland plots. 3. Furthermore, we calculated two ecosystem functions: aphid load (the number of aphid individuals per host plant biomass used as a proxy for herbivory) and parasitism rate. We used structural equation models to explore pathways of direct and indirect effects of plant species richness on higher trophic levels. 4. We found that the densities and richness of species at all trophic levels were influenced by changes in plant species richness. The effects were rarely direct, but instead mediated by the abundance and species richness of aphid host plants and subsequent trophic levels. 5. The herbivore and primary parasitoid levels were most directly affected by changes in plant species richness, with highest insect densities and species richness occurring at intermediate plant species richness. The densities and species richness of secondary parasitoids declined linearly with plant species richness owing to sparser resources, resulting in shorter food chains in communities with the highest plant species richness. 6. Aphid load was highest at intermediate plant species richness and negatively affected by both host plant biomass and host plant species richness. Parasitism rate was mostly affected indirectly via aphid density and overall only weakly negatively related to plant species richness. 7. Our results demonstrate that

  1. Specifications and Construction Methods for Asphalt Concrete and Other Plant-Mix Types, 3rd Edition.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    The purpose of this publication is to assist engineers in the analysis, design and control of paving projects that use asphalt concrete and other asphalt plant-mixes. The scope of this new third edition has been enlarged, and changes necessitated by advances in asphalt technology have been incorporated. Chapters I and II and Appendices A and B…

  2. Responses of constructed plant community to combinations of herbicides, a model for field tests?

    EPA Science Inventory

    As part of its regulation of pesticides, the US Environmental Protection Agency must consider environmental risks, including impacts to non-target plants exposed to pesticide drift. Normally these risk assessments consider impacts to individual species, using greenhouse, dose-re...

  3. 21 CFR 111.20 - What design and construction requirements apply to your physical plant?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... MANUFACTURING, PACKAGING, LABELING, OR HOLDING OPERATIONS FOR DIETARY SUPPLEMENTS Physical Plant and Grounds... use in the manufacture, packaging, labeling, or holding of dietary supplements must: (a) Be suitable... dietary supplements during manufacturing, packaging, labeling, or holding; (c) Permit the use of...

  4. Development of Advanced Technologies to Reduce Design, Fabrication and Construction Costs for Future Nuclear Power Plants

    SciTech Connect

    DiNunzio, Camillo A.; Gupta, Abhinav; Golay, Michael; Luk, Vincent; Turk, Rich; Morrow, Charles; Jin, Geum-Taek

    2002-11-30

    This report presents a summation of the third and final year of a three-year investigation into methods and technologies for substantially reducing the capital costs and total schedule for future nuclear plants. In addition, this is the final technical report for the three-year period of studies.

  5. De novo construction of an expanded transcriptome assembly for the western tarnished plant bug, Lygus hesperus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: The plant bug, Lygus hesperus Knight, is a polyphagous pest of many economically important crops. Despite its pest status, little is known about the molecular mechanisms responsible for much of Lygus biology. Earlier Lygus transcriptome assemblies were either limited by low read depth ...

  6. Effects of ultraviolet radiation on plant cells.

    PubMed

    Hollósy, F

    2002-01-01

    Recent measurements of ozone levels have led to concern that the stratospheric ozone layer is being depleted as a result of contamination with man-made chlorofluorocarbons. Concomitantly, the amounts of solar UV-B radiation reaching the Earth's surface is increasing. UV-B radiation has been shown to be harmful to living organisms, damaging DNA, proteins, lipids and membranes. Plants, which use sunlight for photosynthesis and are unable to avoid exposure to enhanced levels of UV-B radiation, are at risk. Thus, mechanisms by which plants may protect themselves from UV radiation are of particular interest. This review will summarizes the main aspects of ultraviolet radiation on plants at physiological and biochemical level, with particular emphasis on protective structures and mechanisms.

  7. Effect of iodine disinfection products on higher plants

    NASA Technical Reports Server (NTRS)

    Janik, D.; Macler, B.; Macelroy, R. D.; Thorstenson, Y.; Sauer, R.

    1989-01-01

    Iodine is used to disinfect potable water on United States spacecraft. Iodinated potable water will likely be used to grow plants in space. Little is known about the effects of iodine disinfection products on plants. Seeds of select higher plants were germinated in water iodinated using the Shuttle Microbial Check Valve, and water to which measured amounts of iodine was added. Percent germination was decreased in seeds of most species germinated in iodinated water. Beans were most affected. Germination rates, determined from germination half-times, were decreased for beans germinated in iodinated water, and water to which iodide was added. Development was retarded and rootlets were conspicuously absent in bean and several other plant species germinated in iodinated water. Iodide alone did not elicit these responses. Clearly iodine disinfection products can affect higher plants. These effects must be carefully considered for plant experimentation and cultivation in space, and in design and testing of closed environmental life support systems.

  8. Effect of mantras on human beings and plants.

    PubMed

    Karnick, C R

    1983-01-01

    The classic texts of Indian origin record the influence of Mantras on plants and animals. Ayurveda also recognises the importance of this realm of medicine. The author during his various experiments on plants found that these from the stage of seedling to the maturity are effected by certain types of sound waves, especially the Mantras. This study reveals that the plants have shown a positive response to this type of particular sound waves regarding the growth. their efficacy in curing the diseases etc.

  9. Mixed Waste Management Facility (MWMF) closure, Savannah River Plant: Clay cap test section construction report

    SciTech Connect

    Not Available

    1988-02-26

    This report summarizes the information gathered in constructing the clay cap test section. The purpose of the test section was to determine compaction characteristics of four representative kaolin clays and demonstrate in-situ permeability for these clays of 1 {times} 10 {sup {minus}7} cm/sec or less. The final technical specifications with regard to maximum clod size, acceptable ranges of placement water content, lift thickness, and degree of compaction will be based on experience gained from the test section. The data derived from this study will also be used in the development of Quality Assurance (QA) and Quality Control (QC) methods to be used during actual cap construction of the Mixed Waste Management Facility (MWMF) Closure project. 7 tabs.

  10. Evaluation of clogging in planted and unplanted horizontal subsurface flow constructed wetlands: solids accumulation and hydraulic conductivity reduction.

    PubMed

    De Paoli, André Cordeiro; von Sperling, Marcos

    2013-01-01

    This study aimed to evaluate the behaviour of two horizontal subsurface flow constructed wetland units regarding solids build up and clogging of the filter medium. In order to analyse the causes of this process, which is considered the major operational problem of constructed wetlands, studies were carried out to characterize accumulated solids and hydraulic conductivity at specific points of the beds of two wetlands (planted with Typha latifolia and unplanted units) receiving effluent from an upflow anaerobic sludge blanket reactor treating sanitary sewage (population equivalent of 50 inhabitants each unit). The experiments were performed after the units were operating for 2 years and 4 months. This study presents comparative results related to the quantification and characterization of accumulated solids and hydraulic conductivity along the length and width of the filter beds. Approximately 80% of the solids found were inorganic (fixed). Near the inlet end, the rate interstitial solids/attached solids was 5.0, while in the outlet end it was reduced to 1.5. Hydraulic conductivity was lower near the inlet of the units (as expected) and, by comparing the planted wetland with the unplanted, the hydraulic conductivity was lower in the former, resulting in larger undesired surface flow.

  11. Microbial community structure accompanied with electricity production in a constructed wetland plant microbial fuel cell.

    PubMed

    Lu, Lu; Xing, Defeng; Ren, Zhiyong Jason

    2015-11-01

    This study reveals the complex structure of bacterial and archaeal communities associated with a Canna indica plant microbial fuel cell (PMFC) and its electricity production. The PMFC produced a maximum current of 105 mA/m(2) by utilizing rhizodeposits as the sole electron donor without any external nutrient or buffer supplements, which demonstrates the feasibility of PMFCs in practical oligotrophic conditions with low solution conductivity. The microbial diversity was significantly higher in the PMFC than non-plant controls or sediment-only controls, and pyrosequencing and clone library reveal that rhizodeposits conversion to current were carried out by syntrophic interactions between fermentative bacteria (e.g., Anaerolineaceae) and electrochemically active bacteria (e.g., Geobacter). Denitrifying bacteria and acetotrophic methanogens play a minor role in organics degradation, but abundant hydrogenotrophic methanogens and thermophilic archaea are likely main electron donor competitors.

  12. Plant uptake of diclofenac in a mesocosm-scale free water surface constructed wetland by Cyperus alternifolius.

    PubMed

    Zhai, Jun; Rahaman, Md Hasibur; Ji, Jiucui; Luo, Zhiyoung; Wang, Quanfeng; Xiao, Haiwen; Wang, Kunping

    2016-01-01

    This study aimed to assess the uptake of diclofenac, a widely used nonsteroidal anti-inflammatory pharmaceutical, by a macrophyte Cyperus alternifolius in a mesocosm-scale free water surface (FWS) constructed wetland. Quantitative analysis of diclofenac concentrations in water solution and plant tissues was conducted by high performance liquid chromatography analysis after sample pre-treatment with solid-phase extraction and liquid extraction, respectively. The FWS with Cyperus alternifolius obtained a maximum 69.3% diclofenac removal efficiency, while a control system without plant only had a removal efficiency of 2.7% at the end of the experiment period of 70 days. Based on mass balance study of the experimental system, it was estimated that plant uptake and in-plant conversion of diclofenac contributed about 21.4% of the total diclofenac removal in the mesocosm while the remaining 78.6% diclofenac was eliminated through biotic and abiotic conversion of diclofenac in the water phase. Diclofenac on the root surface and in roots, stems and leaves of Cyperus alternifolius was found at the concentrations of 0.15-2.59 μg/g, 0.21-2.66 μg/g, 0.06-0.53 μg/g, and 0.005-0.02 μg/g of fresh weight of plant tissues, respectively. The maximum bioaccumulation factor of diclofenac was calculated in roots (21.04) followed by root surface (20.49), stems (4.19), and leaves (0.16), respectively. Diclofenac translocation potentiality from root to stem was found below 0.5, suggesting a slow and passive translocation process of diclofenac. Current study demonstrated high potential of Cyperus alternifolius for phytoremediation of diclofenac in FWS and can be applied in other engineered ecosystems. PMID:27332847

  13. Plant uptake of diclofenac in a mesocosm-scale free water surface constructed wetland by Cyperus alternifolius.

    PubMed

    Zhai, Jun; Rahaman, Md Hasibur; Ji, Jiucui; Luo, Zhiyoung; Wang, Quanfeng; Xiao, Haiwen; Wang, Kunping

    2016-01-01

    This study aimed to assess the uptake of diclofenac, a widely used nonsteroidal anti-inflammatory pharmaceutical, by a macrophyte Cyperus alternifolius in a mesocosm-scale free water surface (FWS) constructed wetland. Quantitative analysis of diclofenac concentrations in water solution and plant tissues was conducted by high performance liquid chromatography analysis after sample pre-treatment with solid-phase extraction and liquid extraction, respectively. The FWS with Cyperus alternifolius obtained a maximum 69.3% diclofenac removal efficiency, while a control system without plant only had a removal efficiency of 2.7% at the end of the experiment period of 70 days. Based on mass balance study of the experimental system, it was estimated that plant uptake and in-plant conversion of diclofenac contributed about 21.4% of the total diclofenac removal in the mesocosm while the remaining 78.6% diclofenac was eliminated through biotic and abiotic conversion of diclofenac in the water phase. Diclofenac on the root surface and in roots, stems and leaves of Cyperus alternifolius was found at the concentrations of 0.15-2.59 μg/g, 0.21-2.66 μg/g, 0.06-0.53 μg/g, and 0.005-0.02 μg/g of fresh weight of plant tissues, respectively. The maximum bioaccumulation factor of diclofenac was calculated in roots (21.04) followed by root surface (20.49), stems (4.19), and leaves (0.16), respectively. Diclofenac translocation potentiality from root to stem was found below 0.5, suggesting a slow and passive translocation process of diclofenac. Current study demonstrated high potential of Cyperus alternifolius for phytoremediation of diclofenac in FWS and can be applied in other engineered ecosystems.

  14. Prevailing Wage Rates: The Effects on School Construction Costs, Levels of Taxation, and State Reimbursements.

    ERIC Educational Resources Information Center

    Keller, Edward C.; Hartman, William T.

    2001-01-01

    Results of study of impact of Pennsylvania Prevailing Wage Act on 25 school-construction project costs from 1992-97 and effect thereof on local school districts' taxes. All districts had higher construction costs and property taxes. Projects increased construction costs for the Commonwealth and recommends revisions in prevailing wage-rate law.…

  15. Light and Plants. A Series of Experiments Demonstrating Light Effects on Seed Germination, Plant Growth, and Plant Development.

    ERIC Educational Resources Information Center

    Downs, R. J.; And Others

    A brief summary of the effects of light on plant germination, growth and development, including photoperiodism and pigment formation, introduces 18 experiments and demonstrations which illustrate aspects of these effects. Detailed procedures for each exercise are given, the expected results outlined, and possible sources of difficulty discussed.…

  16. Gravitational effects on plant growth hormone concentration

    NASA Technical Reports Server (NTRS)

    Bandurski, R. S.; Schulze, A.

    1983-01-01

    Dolk's (1936) finding that more growth hormone diffuses from the lower side of a gravity-stimulated plant shoot than from the upper side is presently confirmed by means of both an isotope dilution assay and selected ion monitoring-gas chromatography-mass spectrometry, and it is established that the asymmetrically distributed hormone is indole-3-acetic acid (IAA). This is the first physicochemical demonstration that there is more IAA on the lower sides of a geostimulated plant shoot. It is also found that free IAA primarily occurs in the conductive vascular tissues of the shoot, while IAA esters predominate in the growing cortical cells. A highly sensitive gas chromatographic isotope dilution assay shows that the hormone asymmetry also occurs in the nonvascular tissue.

  17. Rules and regulations as potential moderator on the relationship between organizational internal and external factors with effective construction risk management in Nigerian construction companies: A proposed framework

    NASA Astrophysics Data System (ADS)

    Adeleke, A. Q.; Bahaudin, A. Y.; Kamaruddeen, A. M.

    2016-08-01

    Certain organizational internal and external factors have been found to influence effective construction risk management within the construction company which has contributed to massive risk occurrence on the projects. Yet, the influence of the organizational factors such as effective communication, team competency with skills, active leadership, political factor, organizational culture, technology factor and economic factor on effective construction risk management among the construction companies operating in Abuja and Lagos state Nigeria have not received considerable attention. More so, a moderating variable is proposed. This paper proposes rules and regulations as the potential moderator on the relationship between organisational internal factors, external factors and effective construction risk management.

  18. Gravitational effects on plant growth hormone concentration

    NASA Astrophysics Data System (ADS)

    Bandurski, Robert S.; Schulze, Aga

    Numerous studies, particularly those of H. Dolk in the 1930's, established by means of bio-assay, that more growth hormone diffused from the lower, than from the upper side of a gravity-stimulated plant shoot. Now, using an isotope dilution assay, with 4,5,6,7 tetradeutero indole-3-acetic acid as internal standard, and selected ion monitoring-gas chromatography-mass spectrometry as the method of determination, we have confirmed Dolk's finding and established that the asymmetrically distributed hormone is, in fact, indole-3-acetic acid (IAA). This is the first physico-chemical demonstration that there is more free IAA on the lower sides of a geo-stimulated plant shoot. We have also shown that free IAA occurs primarily in the conductive vascular tissues of the shoot, whereas IAA esters predominate in the growing cortical cells. Now, using an especially sensitive gas chromatographic isotope dilution assay we have found that the hormone asymmetry also occurs in the non-vascular tissue. Currently, efforts are directed to developing isotope dilution assays, with picogram sensitivity, to determine how this asymmetry of IAA distribution is attained so as to better understand how the plant perceives the geo-stimulus.

  19. [Treatment effect of constructed wetlands on organic matter in wastewater from pig farm].

    PubMed

    Liao, Xindi; Luo, Shiming

    2002-01-01

    Using plant species Vetiveria zizanioides and Cyperus alternifolius respectively, two constructed wetlands (CWS) with size of 1.0 m x 0.5 m x 0.8 m were established. The purifying function and its change pattern with season, influent concentration and hydraulic retention time (HRT) of the constructed wetlands on the organic matters in wastewater from a pig farm were studied throughout four seasons in the year. The results showed that the two CWS had very stable effects on the removal of COD and BOD, while the organic matters in wastewater changed. The removal rate of COD and BOD was 70% and 80% respectively by HRT 1-2 d in spring. The removal rate of COD reached 90% with the influent of COD 1000-1400 mg.L-1 in summer. The removal rate of COD and BOD was 50-60% and 50% respectively by HRT 1-2 d in autumn. The removal rate of COD reached 70% with the influent of COD 1003 mg.L-1 in winter. There was no significant difference between two CWS in the removal of COD, BOD and SS. The rule of contaminants decreased with the HRT in CWS followed exponential function: Yt = Y0.exp(-kt). The relation between the concentration of contaminants in influent (x) and outflow (y) at the same HRT followed linear relation: y = a + bx.

  20. The effect of low temperatures on ammonia removal in a laboratory-scale constructed wetland

    SciTech Connect

    Lee, M.A.; Stansbury, J.S.; Zhang, T.C.

    1999-05-01

    The effect of low temperatures on ammonia removal in constructed wetlands was studied by running a synthetic wastewater through a model, laboratory-scale gravel-filled constructed wetland (in which no plants were grown). The wetland was operated at temperatures of 5, 11.5, 15, and 23 C in an environmentally controlled chamber. An influent ammonia concentration of 45 mg/L as nitrogen was used to simulate typical domestic wastewater. For temperatures of 5, 11.5, 15, and 23 C, the wetland model achieved ammonia removal and nitrification of 45, 44, 56, and 65%, respectively. Thus, over the 18 C temperature range ammonia-nitrogen removal and nitrification rates varied only 20%. There was a net decrease in nitrogen as water passed through the wetland; this could be the result of cell growth or denitrification. Measurements were taken at the inlet, outlet, and four additional locations along the length of the reactor. Measurements were also taken at three different depths. Along the length of the reactor, nearly all nitrification was achieved in the first half of the reactor, then stopped because of low dissolved oxygen concentrations. Nitrification occurred slightly faster at the top of the reactor than at the bottom.

  1. The Effects of Reinforcing Intermediate Elementary Students to Constructively Use Free Time for Vocational Exploration

    ERIC Educational Resources Information Center

    Hosie, Thomas W.

    1975-01-01

    This study investigated the effectiveness of operant conditioning procedures in stimulating intermediate elementary students to constructively utilize free time for pursuing occupational information. (RC)

  2. Herbivory: effects on plant abundance, distribution and population growth

    PubMed Central

    Maron, John L; Crone, Elizabeth

    2006-01-01

    Plants are attacked by many different consumers. A critical question is how often, and under what conditions, common reductions in growth, fecundity or even survival that occur due to herbivory translate to meaningful impacts on abundance, distribution or dynamics of plant populations. Here, we review population-level studies of the effects of consumers on plant dynamics and evaluate: (i) whether particular consumers have predictably more or less influence on plant abundance, (ii) whether particular plant life-history types are predictably more vulnerable to herbivory at the population level, (iii) whether the strength of plant–consumer interactions shifts predictably across environmental gradients and (iv) the role of consumers in influencing plant distributional limits. Existing studies demonstrate numerous examples of consumers limiting local plant abundance and distribution. We found larger effects of consumers on grassland than woodland forbs, stronger effects of herbivory in areas with high versus low disturbance, but no systematic or unambiguous differences in the impact of consumers based on plant life-history or herbivore feeding mode. However, our ability to evaluate these and other patterns is limited by the small (but growing) number of studies in this area. As an impetus for further study, we review strengths and challenges of population-level studies, such as interpreting net impacts of consumers in the presence of density dependence and seed bank dynamics. PMID:17002942

  3. Worldwide construction

    SciTech Connect

    Bell, L.

    1993-10-18

    Major construction projects in worldwide processing and pipelining are tested, showing capacities, contractors, estimated costs, and time of completion. Total capacity figure in Remarks and completion column includes capacity of project listed. The information is divided into petroleum refineries, petrochemical plants, sulfur recovery units, gas processing plants, related fuel plants (cogeneration, coal gasification, combined cycles), and pipeline companies.

  4. The inhibition and adaptability of four wetland plant species to high concentration of ammonia wastewater and nitrogen removal efficiency in constructed wetlands.

    PubMed

    Wang, Yuhui; Wang, Junfeng; Zhao, Xiaoxiang; Song, Xinshan; Gong, Juan

    2016-02-01

    Four plant species, Typha orientalis, Scirpus validus, Canna indica and Iris tectorum were selected to assess their physiological response and effects on nitrogen and COD removal to high total ammoniacal nitrogen (TAN) in constructed wetlands. Results showed that high TAN caused decreased relative growth rate, net photosynthetic rate, and leaf transpiration. C. indica and T. orientalis showed higher TAN adaptability than S. validus and I. tectorum. Below TAN of 200 mg L(-1), growth of C. indica and T. orientalis was less affected or even stimulated at TAN range 100-200 mg L(-1). However, S. validus and I. tectorum was obviously suppressed when TAN was above 100 mg L(-1). High TAN generated obvious oxidative stress showing increased proline and malondialdehyde contents, and superoxide dismutase was inhibited. It indicated that the threshold for plant self-bioremediation against high TAN was 200 mg L(-1). What's more, planted CWs showed higher nitrogen and COD removal. Removal rate of C. indica and T. orientalis was higher than S. validus and I. tectorum.

  5. Ecological effects of roads on the plant diversity of coastal wetland in the Yellow River Delta.

    PubMed

    Li, Yunzhao; Yu, Junbao; Ning, Kai; Du, Siyao; Han, Guangxuan; Qu, Fanzhu; Wang, Guangmei; Fu, Yuqin; Zhan, Chao

    2014-01-01

    The 26 sample sites in 7 study plots adjacent to asphalt road and earth road in coastal wetland in the Yellow River Delta were selected to quantify plant diversity using quadrat sampling method in plant bloom phase of July and August 2012. The indice of β T and Jaccard's coefficient were applied to evaluate the species diversity. The results showed that the plant diversities and alien plants were high in the range of 0-20 m to the road verge. There were more exotics and halophytes in plots of asphalt roadside than that of earth roadside. However, proportion of halophytes in habitats of asphalt roadsides was lower than that of earth roadside. By comparing β-diversity, there were more common species in the asphalt roadsides than that in the earth roadsides. The similarity of plant communities in studied plots of asphalt roadsides and earth roadsides increased with increasing the distance to road verge. The effect range of roads for plant diversity in study region was about 20 m to road verge. Our results indicate that the construction and maintenance of roads in wetland could increase the plant species diversities of communities and risk of alien species invasion.

  6. Ecological Effects of Roads on the Plant Diversity of Coastal Wetland in the Yellow River Delta

    PubMed Central

    Li, Yunzhao; Du, Siyao; Han, Guangxuan; Qu, Fanzhu; Wang, Guangmei; Fu, Yuqin; Zhan, Chao

    2014-01-01

    The 26 sample sites in 7 study plots adjacent to asphalt road and earth road in coastal wetland in the Yellow River Delta were selected to quantify plant diversity using quadrat sampling method in plant bloom phase of July and August 2012. The indice of βT and Jaccard's coefficient were applied to evaluate the species diversity. The results showed that the plant diversities and alien plants were high in the range of 0–20 m to the road verge. There were more exotics and halophytes in plots of asphalt roadside than that of earth roadside. However, proportion of halophytes in habitats of asphalt roadsides was lower than that of earth roadside. By comparing β-diversity, there were more common species in the asphalt roadsides than that in the earth roadsides. The similarity of plant communities in studied plots of asphalt roadsides and earth roadsides increased with increasing the distance to road verge. The effect range of roads for plant diversity in study region was about 20 m to road verge. Our results indicate that the construction and maintenance of roads in wetland could increase the plant species diversities of communities and risk of alien species invasion. PMID:25147872

  7. USING POTATOES IN PROPAGATION TESTS FOR NONTARGET PLANT EFFECTS

    EPA Science Inventory

    Current tests required for pesticide registration under the FIFRA only investigate seedling emergence and early growth. Previous research with sulfonylurea (SU) herbicides has shown that significant impacts can occur to plant reproduction with little or no visible effect on vege...

  8. Plant diversity effects on root decomposition in grasslands

    NASA Astrophysics Data System (ADS)

    Chen, Hongmei; Mommer, Liesje; van Ruijven, Jasper; de Kroon, Hans; Gessler, Arthur; Scherer-Lorenzen, Michael; Wirth, Christian; Weigelt, Alexandra

    2016-04-01

    Loss of plant diversity impairs ecosystem functioning. Compared to other well-studied processes, we know little about whether and how plant diversity affects root decomposition, which is limiting our knowledge on biodiversity-carbon cycling relationships in the soil. Plant diversity potentially affects root decomposition via two non-exclusive mechanisms: by providing roots of different substrate quality and/or by altering the soil decomposition environment. To disentangle these two mechanisms, three decomposition experiments using a litter-bag approach were conducted on experimental grassland plots differing in plant species richness, functional group richness and functional group composition (e.g. presence/absence of grasses, legumes, small herbs and tall herbs, the Jena Experiment). We studied: 1) root substrate quality effects by decomposing roots collected from the different experimental plant communities in one common plot; 2) soil decomposition environment effects by decomposing standard roots in all experimental plots; and 3) the overall plant diversity effects by decomposing community roots in their 'home' plots. Litter bags were installed in April 2014 and retrieved after 1, 2 and 4 months to determine the mass loss. We found that mass loss decreased with increasing plant species richness, but not with functional group richness in the three experiments. However, functional group presence significantly affected mass loss with primarily negative effects of the presence of grasses and positive effects of the presence of legumes and small herbs. Our results thus provide clear evidence that species richness has a strong negative effect on root decomposition via effects on both root substrate quality and soil decomposition environment. This negative plant diversity-root decomposition relationship may partly account for the positive effect of plant diversity on soil C stocks by reducing C loss in addition to increasing primary root productivity. However, to fully

  9. Preschoolers Effectively Tutor Novice Classmates in a Block Construction Task.

    ERIC Educational Resources Information Center

    Johnson-Pynn, Julie S.; Nisbet, Valerie S.

    2002-01-01

    Examined whether preschool-age experts (with task experience) would spontaneously assist novices (without task experience) when working in pairs on constructing a house with blocks. Found that experts were more likely to provide nonverbal assistance than verbal assistance, with modeling how to combine blocks being most frequent. The most frequent…

  10. Arsenic Toxicity: The Effects on Plant Metabolism

    PubMed Central

    Finnegan, Patrick M.; Chen, Weihua

    2012-01-01

    The two forms of inorganic arsenic, arsenate (AsV) and arsenite (AsIII), are easily taken up by the cells of the plant root. Once in the cell, AsV can be readily converted to AsIII, the more toxic of the two forms. AsV and AsIII both disrupt plant metabolism, but through distinct mechanisms. AsV is a chemical analog of phosphate that can disrupt at least some phosphate-dependent aspects of metabolism. AsV can be translocated across cellular membranes by phosphate transport proteins, leading to imbalances in phosphate supply. It can compete with phosphate during phosphorylation reactions, leading to the formation of AsV adducts that are often unstable and short-lived. As an example, the formation and rapid autohydrolysis of AsV-ADP sets in place a futile cycle that uncouples photophosphorylation and oxidative phosphorylation, decreasing the ability of cells to produce ATP and carry out normal metabolism. AsIII is a dithiol reactive compound that binds to and potentially inactivates enzymes containing closely spaced cysteine residues or dithiol co-factors. Arsenic exposure generally induces the production of reactive oxygen species that can lead to the production of antioxidant metabolites and numerous enzymes involved in antioxidant defense. Oxidative carbon metabolism, amino acid and protein relationships, and nitrogen and sulfur assimilation pathways are also impacted by As exposure. Readjustment of several metabolic pathways, such as glutathione production, has been shown to lead to increased arsenic tolerance in plants. Species- and cultivar-dependent variation in arsenic sensitivity and the remodeling of metabolite pools that occurs in response to As exposure gives hope that additional metabolic pathways associated with As tolerance will be identified. PMID:22685440

  11. Construction of a SSR-based genetic map and identification of QTLs for catechins content in tea plant (Camellia sinensis).

    PubMed

    Ma, Jian-Qiang; Yao, Ming-Zhe; Ma, Chun-Lei; Wang, Xin-Chao; Jin, Ji-Qiang; Wang, Xue-Min; Chen, Liang

    2014-01-01

    Catechins are the most important bioactive compounds in tea, and have been demonstrated to possess a wide variety of pharmacological activities. To characterize quantitative trait loci (QTLs) for catechins content in the tender shoots of tea plant, we constructed a moderately saturated genetic map using 406 simple sequence repeat (SSR) markers, based on a pseudo-testcross population of 183 individuals derived from an intraspecific cross of two Camellia sinensis varieties with diverse catechins composition. The map consisted of fifteen linkage groups (LGs), corresponding to the haploid chromosome number of tea plant (2n = 2x = 30). The total map length was 1,143.5 cM, with an average locus spacing of 2.9 cM. A total of 25 QTLs associated with catechins content were identified over two measurement years. Of these, nine stable QTLs were validated across years, and clustered into four main chromosome regions on LG03, LG11, LG12 and LG15. The population variability explained by each QTL was predominantly at moderate-to-high levels and ranged from 2.4% to 71.0%, with an average of 17.7%. The total number of QTL for each trait varied from four to eight, while the total population variability explained by all QTLs for a trait ranged between 38.4% and 79.7%. This is the first report on the identification of QTL for catechins content in tea plant. The results of this study provide a foundation for further cloning and functional characterization of catechin QTLs for utilization in improvement of tea plant.

  12. Construction and operation of the 4MWth twin-bed PFBC pilot plant for operation reliability test

    SciTech Connect

    Oki, Katsuya; Nishimura, Tsukasa; Yoshioka, Susumu; Yokoyama, Toshiaki

    1995-12-31

    Babcock-Hitachi (BHK) together with Hitachi, Ltd. has been involved in the development and planning of a large-scale coal fired PFBC combined cycle power plant. Based on its past experience in operating a 150KWth benchscale PFBC, a 2MWth PFBC of 4m bed height, and a 15MWth PFBC, several technological ideas are being incorporated into the design of large-scale PFBC boilers. These ideas include: (1) A twin-bed concept in the steam generator for improved efficiency. (2) Employment of SNCR and SCR for stringent NOx regulations. The former idea is to design a steam generator with two beds each contained in separate pressure vessels. One of the two beds of the same dimensions contains the evaporator and superheater, while the other bed contains the reheater and superheater. In this setup, reheater steam temperature can be controlled by adjusting the bed height independently from the other bed without the usual spray tempering strategy under steady state conditions, thus the loss caused by spraying can be eliminated and the overall plant efficiency improved. Aiming at demonstrating the operation and control of a PFBC that uses those technologies and also improving the unit operability, a 4MWth (two 2MWth beds) PFBC pilot plant with necessary auxiliary equipment such as a paste fuel system, an ash withdrawal system, and a gas cleaning system was planned and constructed in 1994. This paper presents the design features of the 4MWth PFBC pilot plant and operating experiences obtained during the initial test period. A brief review of a future large-scale PFBC boiler design concept is also included.

  13. Current status of design and construction of ENCOAL Mild Gasification Plant

    SciTech Connect

    Frederick, J.P.; Siddoway, M.A.; Coolidge, D.W.

    1992-11-01

    The ENCOAL project is demonstrating for the first time the integrated operation of several process steps: a. Coal drying on a rotary grate using convective heatin; b. Coal devolatilization on a rotary grate using convective heating; c. Hot particulate removal with cyclones integral solids cooling; and deactivation-passivation; e. Combustors operating on low-Btu gas from internal streams; f. Solids stabilization for storage and shipment; g. Computer control and optimization of a mild coal gasification process. The product fuels are expected to be used economically in commercial boilers and furnaces and to significantly reduce sulfur emissions at industrial and utility facilities currently burning high sulfur bituminous fuels or fuel oils thereby reducing acid rain-causing pollutants. The design and construction of the ENCOAL demonstration plan was done on a fast track basis, that is, these activities were extensively overlapped.

  14. Current status of design and construction of ENCOAL Mild Gasification Plant

    SciTech Connect

    Frederick, J.P.; Siddoway, M.A.; Coolidge, D.W.

    1992-01-01

    The ENCOAL project is demonstrating for the first time the integrated operation of several process steps: a. Coal drying on a rotary grate using convective heatin; b. Coal devolatilization on a rotary grate using convective heating; c. Hot particulate removal with cyclones integral solids cooling; and deactivation-passivation; e. Combustors operating on low-Btu gas from internal streams; f. Solids stabilization for storage and shipment; g. Computer control and optimization of a mild coal gasification process. The product fuels are expected to be used economically in commercial boilers and furnaces and to significantly reduce sulfur emissions at industrial and utility facilities currently burning high sulfur bituminous fuels or fuel oils thereby reducing acid rain-causing pollutants. The design and construction of the ENCOAL demonstration plan was done on a fast track basis, that is, these activities were extensively overlapped.

  15. Effect of plants on sunspace passive solar heating

    SciTech Connect

    Best, E.D.; McFarland, R.D.

    1985-01-01

    The effect of plants on sunspace thermal performance is investigated, based on experiments done in Los Alamos using two test rooms with attached sunspaces, which were essentially identical except for the presence of plants in one. Performance is related to plant transpiration, evaporation from the soil, condensation on the glazing and the absorbtance of solar energy by the lightweight leaves. Performance effects have been quantified by measurements of auxiliary heat consumption in the test rooms and analyzed by means of energy balance calculations. A method for estimating the transpiration rate is presented.

  16. [Stress effects of simulant acid rain on three woody plants].

    PubMed

    Zhou, Qing; Huang, Xiaohua; Liu, Xiaolin

    2002-09-01

    Osmanthus fragrana, Chimonanthus praecox and Prunus persica were used as materials to investigate the effect of simulant acid rain on chlorophyll (Chl) content, cell membrane permeability(L%), the content of proline (Pro) and malondialdehyde (MDA) in three woody plants with different resistance, and effects of the light and dark conditions on acid rain injury. The results showed that the change degree of four kinds of physiological and biochemical indexes for these woody plants was as sequence: Osmanthus fragrana > Chimonanthus praecox > Prunus persica. The change of chlorophyll content in these woody plants was not obviously when acid rain stress was influenced by the light and dark.

  17. Fast-forward generation of effective artificial small RNAs for enhanced antiviral defense in plants

    PubMed Central

    Carbonell, Alberto; Carrington, James C.; Daròs, José-Antonio

    2016-01-01

    Artificial small RNAs (sRNAs) are short ≈21-nt non-coding RNAs engineered to inactivate sequence complementary RNAs. In plants, they have been extensively used to silence cellular transcripts in gene function analyses and to target invading RNA viruses to induce resistance. Current artificial sRNA-based antiviral resistance in plants is mainly limited to a single virus, and is jeopardized by the emergence of mutations in the artificial sRNA target site or by the presence of co-infecting viruses. Hence, there is a need to further develop the artificial sRNA approach to generate more broad and durable antiviral resistance in plants. A recently developed toolbox allows for the time and cost-effective large-scale production of artificial sRNA constructs in plants. The toolbox includes the P-SAMS web tool for the automated design of artificial sRNAs, and a new generation of artificial microRNA and synthetic trans-acting small interfering RNA (syn-tasiRNA) vectors for direct cloning and high expression of artificial sRNAs. Here we describe how the simplicity and high-throughput capability of these new technologies should accelerate the study of artificial sRNA-based antiviral resistance in plants. In particular, we discuss the potential of the syn-tasiRNA approach as a promising strategy for developing more effective, durable and broad antiviral resistance in plants. PMID:26925463

  18. The effects of plant diversity on nitrous oxide emissions in hydroponic microcosms

    NASA Astrophysics Data System (ADS)

    Sun, Hongying; Zhang, Chongbang; Song, Changchun; Chang, Scott X.; Gu, Baojing; Chen, Zhengxin; Peng, Changhui; Chang, Jie; Ge, Ying

    2013-10-01

    Previous studies have shown that plant diversity can improve the wastewater purification efficiency of constructed wetlands (CWs), but its effect on the nitrous oxide (N2O) emission in CWs has been unknown. To investigate the effect of plant diversity on the N2O emission, we established four plant species richness levels (each level containing 1, 2, 3 and 4 species, respectively) by using 96 hydroponic microcosms. Results showed that plant species richness enhanced the N2O emission, ranging from 27.1 to 115.4 μg N2O m-2 d-1, and improved nitrate removal (P < 0.001). The presence of Phalaris arundinacea within a given plant community increased the N2O emission (P < 0.001). The presence of Rumex japonicas had no influence on the N2O emissions (P > 0.05), but improved nitrogen removal (P < 0.001). Hence, our study highlights the importance of both plant species richness and species identity in mediating the N2O emission and nitrogen removal in CWs.

  19. Inhibitory effect of seven Allium plants upon three Aspergillus species.

    PubMed

    Yin, M C; Tsao, S M

    1999-08-01

    Antifungal activity and minimal fungicidal concentration (MFC) of extracts of garlic, bakeri garlic, Chinese leek, Chinese chive, scallion, onion bulb and shallot bulb against Aspergillus niger, A. flavus and A. fumigatus were examined. These Allium plants possessed antifungal activity, with garlic showing the lowest MFC. With the exception of scallion, the inhibitory effect of Allium plants against three Aspergillus species decreased with increasing incubation and heating temperature (P < 0.05). Acetic acid treatments of the extracts increased the inhibitory effect for all plants against three fungi (P < 0.05), and there was no significant difference in this effect among the three pH (2, 4, 6) treatments (P > 0.05) investigated. Acetic acid, at pH = 4, plus heat treatments of the extracts resulted in a greater inhibitory effect for all Allium plants against the three fungi than heat treatment alone (P < 0.05). Treatments of the extracts with NaCl, at concentrations of 0.2 and 0.4 M, did not affect the inhibitory effect of the plant extracts. The combination of acetic acid plus Allium plants was indicated to be an effective way to inhibit fungal growth. PMID:10477070

  20. Cyclotron-based effects on plant gravitropism

    NASA Astrophysics Data System (ADS)

    Kordyum, E.; Sobol, M.; Kalinina, Ia.; Bogatina, N.; Kondrachuk, A.

    Primary roots exhibit positive gravitropism and grow in the direction of the gravitational vector, while shoots respond negatively and grow opposite to the gravitational vector. We first demonstrated that the use of a weak combined magnetic field (CMF), which is comprised of a permanent magnetic field and an alternating magnetic field with the frequency resonance of the cyclotron frequency of calcium ions, can change root gravitropism from a positive direction to negative direction. Two-day-old cress seedlings were gravistimulated in a chamber that was placed into a μ-metal shield where this CMF was created. Using this "new model" of a root gravitropic response, we have studied some of its components including the movement of amyloplasts-statoliths in root cap statocytes and the distribution of Ca 2+ ions in the distal elongation zone during gravistimulation. Unlike results from the control, amyloplasts did not sediment in the distal part of a statocyte, and more Ca 2+ accumulation was observed in the upper side of a gravistimulated root for seedlings treated with the CMF. For plants treated with the CMF, it appears that a root gravitropic reaction occurs by a normal physiological process resulting in root bending although in the opposite direction. These results support the hypothesis that both the amyloplasts in the root cap statocytes and calcium are important signaling components in plant gravitropism.

  1. Trace gases generated in closed plant cultivation systems and their effects on plant growth.

    PubMed

    Tani, A; Kiyota, M; Aiga, I

    1995-12-01

    accumulation. Thus, ethylene release characteristics were clarified and an effect of ethylene on lettuce growth was revealed. These findings are useful for determination of a threshold level of ethylene and a capacity of ethylene removal system in CELSS. On the other hand, a possibility of plant growth diagnosis by measuring ethylene concentrations was evaluated. As a result, it became clear that the measurement of ethylene concentration in CELSS is one of the useful non-destructive measurement methods for plant growth diagnosis. Further research is needed to investigate the applicability of the method to environmental stresses other than Ni and Co in nutrient solution.

  2. Trace gases generated in closed plant cultivation systems and their effects on plant growth.

    PubMed

    Tani, A; Kiyota, M; Aiga, I

    1995-12-01

    accumulation. Thus, ethylene release characteristics were clarified and an effect of ethylene on lettuce growth was revealed. These findings are useful for determination of a threshold level of ethylene and a capacity of ethylene removal system in CELSS. On the other hand, a possibility of plant growth diagnosis by measuring ethylene concentrations was evaluated. As a result, it became clear that the measurement of ethylene concentration in CELSS is one of the useful non-destructive measurement methods for plant growth diagnosis. Further research is needed to investigate the applicability of the method to environmental stresses other than Ni and Co in nutrient solution. PMID:11541892

  3. The role of plant uptake on the removal of organic matter and nutrients in subsurface flow constructed wetlands: a simulation study.

    PubMed

    Langergraber, G

    2005-01-01

    Plants in constructed wetlands have several functions related to the treatment processes. It is generally agreed that nutrient uptake is a minor factor in constructed wetlands treating wastewater compared to the loadings applied. For low loaded systems plant uptake can contribute a significant amount to nutrient removal. The contribution of plant uptake is simulated for different qualities of water to be treated using the multi-component reactive transport module CW2D. CW2D is able to describe the biochemical elimination and transformation processes for organic matter, nitrogen and phosphorus in subsurface flow constructed wetlands. The model for plant uptake implemented describes nutrient uptake coupled to water uptake. Literature values are used to calculate potential water and nutrient uptake rates. For a constructed wetland treating municipal wastewater a potential nutrient uptake of about 1.9% of the influent nitrogen and phosphorus load can be expected. For lower loaded systems the potential uptake is significantly higher, e.g. 46% of the nitrogen load for treatment of greywater. The potential uptake rates could only be simulated for high loaded systems i.e. constructed wetlands treating wastewater. For low loaded systems the nutrient concentrations in the liquid phase were too low to simulate the potential uptake rates using the implemented model for plant uptake.

  4. Effects of bisphenol A on chlorophyll fluorescence in five plants.

    PubMed

    Zhang, Jiazhi; Wang, Lihong; Li, Man; Jiao, Liya; Zhou, Qing; Huang, Xiaohua

    2015-11-01

    The aim of this study was to evaluate the effects of bisphenol A (BPA) on plant photosynthesis and determine whether the photosynthetic response to BPA exposure varies in different plants. Chlorophyll fluorescence techniques were used to investigate the effects of BPA on chlorophyll fluorescence parameters in tomato (Lycopersicum esculentum), lettuce (Lactuca sativa), soybean (Glycine max), maize (Zea mays), and rice (Oryza sativa) seedlings. Low-dose (1.5 or 3.0 mg L(-1)) BPA exposure improved photosystem II efficiency, increased the absorption and conversion efficiency of primary light energy, and accelerated photosynthetic electron transport in each plant, all of which increased photosynthesis. These effects weakened or disappeared after the withdrawal of BPA. High-dose (10.0 mg L(-1)) BPA exposure damaged the photosystem II reaction center, inhibited the photochemical reaction, and caused excess energy to be released as heat. These effects were more evident after the highest BPA dose (17.2 mg L(-1)), but they weakened after the withdrawal of BPA. The magnitude of BPA exposure effects on the chlorophyll fluorescence parameters in the five plants followed the order: lettuce > tomato > soybean > maize > rice. The opposite order was observed following the removal of BPA. In conclusion, the chlorophyll fluorescence response in plants exposed to BPA depended on BPA dose and plant species.

  5. Two Poplar-Associated Bacterial Isolates Induce Additive Favorable Responses in a Constructed Plant-Microbiome System

    PubMed Central

    Timm, Collin M.; Pelletier, Dale A.; Jawdy, Sara S.; Gunter, Lee E.; Henning, Jeremiah A.; Engle, Nancy; Aufrecht, Jayde; Gee, Emily; Nookaew, Intawat; Yang, Zamin; Lu, Tse-Yuan; Tschaplinski, Timothy J.; Doktycz, Mitchel J.; Tuskan, Gerald A.; Weston, David J.

    2016-01-01

    The biological function of the plant-microbiome system is the result of contributions from the host plant and microbiome members. The Populus root microbiome is a diverse community that has high abundance of β- and γ-Proteobacteria, both classes which include multiple plant-growth promoting representatives. To understand the contribution of individual microbiome members in a community, we studied the function of a simplified community consisting of Pseudomonas and Burkholderia bacterial strains isolated from Populus hosts and inoculated on axenic Populus cutting in controlled laboratory conditions. Both strains increased lateral root formation and root hair production in Arabidopsis plate assays and are predicted to encode for different functions related to growth and plant growth promotion in Populus hosts. Inoculation individually, with either bacterial isolate, increased root growth relative to uninoculated controls, and while root area was increased in mixed inoculation, the interaction term was insignificant indicating additive effects of root phenotype. Complementary data including photosynthetic efficiency, whole-transcriptome gene expression and GC-MS metabolite expression data in individual and mixed inoculated treatments indicate that the effects of these bacterial strains are unique and additive. These results suggest that the function of a microbiome community may be predicted from the additive functions of the individual members. PMID:27200001

  6. Construction of an Ultrahigh Pressure Liquid Chromatography-Tandem Mass Spectral Library of Plant Natural Products and Comparative Spectral Analyses.

    PubMed

    Lei, Zhentian; Jing, Li; Qiu, Feng; Zhang, Hua; Huhman, David; Zhou, Zhiqin; Sumner, Lloyd W

    2015-07-21

    A plant natural product tandem mass spectral library has been constructed using authentic standards and purified compounds. Currently, the library contains 1734 tandem mass spectra for 289 compounds, with the majority (76%) of the compounds being plant phenolics such as flavonoids, isoflavonoids, and phenylpropanoids. Tandem mass spectra and chromatographic retention data were acquired on a triple quadrupole mass spectrometer coupled to an ultrahigh pressure liquid chromatograph using six different collision energies (CEs) (10-60 eV). Comparative analyses of the tandem mass spectral data revealed that the loss of ring substituents preceded the C-ring opening during the fragmentation of flavonoids and isoflavonoids. At lower CE (i.e., 10 and 20 eV), the flavonoids and isoflavonoid central ring structures typically remained intact, and fragmentation was characterized by the loss of the substituents (i.e., methyl and glycosyl groups). At higher CE, the flavonoid and isoflavonoid core ring systems underwent C-ring cleavage and/or rearrangement depending on the structure, particularly hydroxylation patterns. In-source electrochemical oxidation was observed for phenolics that had ortho-diphenol moieties (i.e., vicinal hydroxyl groups on the aromatic rings). The ortho-diphenols were oxidized to ortho-quinones, yielding an intensive and, in most cases, a base ion peak corresponding to a [(M - 2H) - H](-) ion in their mass spectra. The library also contains reverse-phase retention times, allowing for the construction, validation, and testing of an artificial neural network retention prediction of other flavonoids and isoflavonoids not contained within the library. The library is freely available for nonprofit, academic use and it can be downloaded at http://www.noble.org/apps/Scientific/WebDownloadManager/DownloadArea.aspx. PMID:26107650

  7. Construction of an Ultrahigh Pressure Liquid Chromatography-Tandem Mass Spectral Library of Plant Natural Products and Comparative Spectral Analyses.

    PubMed

    Lei, Zhentian; Jing, Li; Qiu, Feng; Zhang, Hua; Huhman, David; Zhou, Zhiqin; Sumner, Lloyd W

    2015-07-21

    A plant natural product tandem mass spectral library has been constructed using authentic standards and purified compounds. Currently, the library contains 1734 tandem mass spectra for 289 compounds, with the majority (76%) of the compounds being plant phenolics such as flavonoids, isoflavonoids, and phenylpropanoids. Tandem mass spectra and chromatographic retention data were acquired on a triple quadrupole mass spectrometer coupled to an ultrahigh pressure liquid chromatograph using six different collision energies (CEs) (10-60 eV). Comparative analyses of the tandem mass spectral data revealed that the loss of ring substituents preceded the C-ring opening during the fragmentation of flavonoids and isoflavonoids. At lower CE (i.e., 10 and 20 eV), the flavonoids and isoflavonoid central ring structures typically remained intact, and fragmentation was characterized by the loss of the substituents (i.e., methyl and glycosyl groups). At higher CE, the flavonoid and isoflavonoid core ring systems underwent C-ring cleavage and/or rearrangement depending on the structure, particularly hydroxylation patterns. In-source electrochemical oxidation was observed for phenolics that had ortho-diphenol moieties (i.e., vicinal hydroxyl groups on the aromatic rings). The ortho-diphenols were oxidized to ortho-quinones, yielding an intensive and, in most cases, a base ion peak corresponding to a [(M - 2H) - H](-) ion in their mass spectra. The library also contains reverse-phase retention times, allowing for the construction, validation, and testing of an artificial neural network retention prediction of other flavonoids and isoflavonoids not contained within the library. The library is freely available for nonprofit, academic use and it can be downloaded at http://www.noble.org/apps/Scientific/WebDownloadManager/DownloadArea.aspx.

  8. Effect of thermal power plant emissions on Catharanthus roseus L

    SciTech Connect

    Khan, A.M.; Pandey, V.; Shukla, J.; Singh, N.; Yunus, M.; Singh, S.N.; Ahmad, K.J. )

    1990-06-01

    Most of the industrialized nations depend largely on the combustion of fossil fuels for their energy requirements. During the past few years in India quite a few thermal power plants have been commissioned to cater to the increasing energy requirements. As most of the power plants are coal-fired, a complex mixture of several pollutants is released in the atmosphere on the combustion of coal. Leaves by virtue of their unique position on plants and their functions, experience the maximum brunt of exposure and undergo certain changes in form, structure and function with the changes in surrounding environs, and such modifications are likely to serve as markers of environmental pollution. The present paper deals with the long term exposure effects of thermal power plant emissions on Catharanthus roseus L. - a common perennial shrub, with glossy leaves and white, mauve or pink colored flowers and of great medicinal value is grown as an ornamental plant all over the country.

  9. Elevated atmospheric carbon dioxide effects on cotton plant residue decomposition

    SciTech Connect

    Torbert, H.A.; Prior, S.A.; Rogers, H.H.

    1995-09-01

    Assessing the impact of elevated atmospheric CO{sub 2} concentration on the global environment is hampered due to a lack of understanding of global C cycling. Carbon fixed within plant biomass ultimately enters the soil via plant residues, but the effects of elevated-CO{sub 2}-grown plant material on decomposition rates and long-term soil C storage are unknown. The objective of this study was to determine the decomposition rate of plant residues grown under an elevated CO{sub 2} environment as affected by soil type. Cotton (Gossypium hirsutum L. `Delta Pine 77`) samples were collected from a free-air CO{sub 2} enrichment (550 {mu}L L{sup -1}) experiment. The plant residues were incubated under ambient CO{sub 2} conditions to determine decomposition rates of leaves, stems, and roots and potential N and P mineralization-immobilization in three soil series. No significant difference was observed between plant residue grown under CO{sub 2} enrichment vs. ambient CO{sub 2} conditions for soil respiration or P mineralization-immobilization. Significantly greater net N immobilization was observed during the incubation in all soil types for plant residue grown at elevated CO{sub 2}. These results indicate that while decomposition of plant residue may not be reduced by CO{sub 2} enrichment, N dynamics may be markedly changed. 32 refs., 5 figs., 3 tabs.

  10. Behaviour of pharmaceuticals and personal care products in constructed wetland compartments: Influent, effluent, pore water, substrate and plant roots.

    PubMed

    Hijosa-Valsero, María; Reyes-Contreras, Carolina; Domínguez, Carmen; Bécares, Eloy; Bayona, Josep M

    2016-02-01

    Seven mesocosm-scale constructed wetlands (CWs) with different design configurations, dealing with primary-treated urban wastewater, were assessed for the concentration, distribution and fate of ten pharmaceutical and personal care products (PPCPs) [ibuprofen, ketoprofen, naproxen, diclofenac, salicylic acid, caffeine, carbamazepine, methyl dihydrojasmonate, galaxolide and tonalide] and eight of their transformation products (TPs). Apart from influent and effluent, various CW compartments were analysed, namely, substrate, plant roots and pore water. PPCP content in pore water depended on the specific CW configuration. Macrophytes can take up PPCPs through their roots. Ibuprofen, salicylic acid, caffeine, methyl dihydrojasmonate, galaxolide and tonalide were present on the root surface with a predominance of galaxolide and caffeine in all the planted systems. Naproxen, ibuprofen, salicylic acid, methyl dihydrojasmonate, galaxolide and tonalide were uptaken by the roots. In order to better understand the removal processes, biomass measurement and biodegradability studies through the characterization of internal-external isomeric linear alkylbenzenes present on the gravel bed were performed. Three TPs namely, ibuprofen-amide, 3-ethylbenzophenone and 4-hydroxy-diclofenac were identified for the first time in wetland pore water and effluent water, which suggests de novo formation (they were not present in the influent). Conversely, O-desmethyl-naproxen was degraded through the wetland passage since it was detected in the influent but not in the subsequent treatment stages. Biodegradation pathways are therefore suggested for most of the studied PPCPs in the assessed CWs.

  11. Behaviour of pharmaceuticals and personal care products in constructed wetland compartments: Influent, effluent, pore water, substrate and plant roots.

    PubMed

    Hijosa-Valsero, María; Reyes-Contreras, Carolina; Domínguez, Carmen; Bécares, Eloy; Bayona, Josep M

    2016-02-01

    Seven mesocosm-scale constructed wetlands (CWs) with different design configurations, dealing with primary-treated urban wastewater, were assessed for the concentration, distribution and fate of ten pharmaceutical and personal care products (PPCPs) [ibuprofen, ketoprofen, naproxen, diclofenac, salicylic acid, caffeine, carbamazepine, methyl dihydrojasmonate, galaxolide and tonalide] and eight of their transformation products (TPs). Apart from influent and effluent, various CW compartments were analysed, namely, substrate, plant roots and pore water. PPCP content in pore water depended on the specific CW configuration. Macrophytes can take up PPCPs through their roots. Ibuprofen, salicylic acid, caffeine, methyl dihydrojasmonate, galaxolide and tonalide were present on the root surface with a predominance of galaxolide and caffeine in all the planted systems. Naproxen, ibuprofen, salicylic acid, methyl dihydrojasmonate, galaxolide and tonalide were uptaken by the roots. In order to better understand the removal processes, biomass measurement and biodegradability studies through the characterization of internal-external isomeric linear alkylbenzenes present on the gravel bed were performed. Three TPs namely, ibuprofen-amide, 3-ethylbenzophenone and 4-hydroxy-diclofenac were identified for the first time in wetland pore water and effluent water, which suggests de novo formation (they were not present in the influent). Conversely, O-desmethyl-naproxen was degraded through the wetland passage since it was detected in the influent but not in the subsequent treatment stages. Biodegradation pathways are therefore suggested for most of the studied PPCPs in the assessed CWs. PMID:26702554

  12. Floral Transcriptome Sequencing for SSR Marker Development and Linkage Map Construction in the Tea Plant (Camellia sinensis)

    PubMed Central

    Wei, Kang; Zhang, Cheng-Cai; Wu, Li-Yun; Qi, Gui-Nian; Cheng, Hao; Zhang, Qiang; Cui, Qing-Mei; Liang, Jin-Bo

    2013-01-01

    Despite the worldwide consumption and high economic importance of tea, the plant (Camellia sinensis) is not well studied in molecular biology. Under the few circumstances in which the plant is studied, C. sinensis flowers, which are important for reproduction and cross-breeding, receive less emphasis than investigation of its leaves or roots. Using high-throughput Illumina RNA sequencing, we analyzed a C. sinensis floral transcriptome, and 26.9 million clean reads were assembled into 75,531 unigenes averaging 402 bp. Among them, 50,792 (67.2%) unigenes were annotated with a BLAST search against the NCBI Non-Redundant (NR) database and 10,290 (16.67%) were detected that contained one or more simple sequence repeats (SSRs). From these SSR-containing sequences, 2,439 candidate SSR markers were developed and 720 were experimentally tested, validating 431 (59.9%) novel polymorphic SSR markers for C. sinensis. Then, a consensus SSR-based linkage map was constructed that covered 1,156.9 cM with 237 SSR markers distributed in 15 linkage groups. Both transcriptome information and the genetic map of C. sinensis presented here offer a valuable foundation for molecular biology investigations such as functional gene isolation, quantitative trait loci mapping, and marker-assisted selection breeding in this important species. PMID:24303059

  13. Feasibility of constructed wetland planted with Leersia hexandra Swartz for removing Cr, Cu and Ni from electroplating wastewater.

    PubMed

    You, Shao-Hong; Zhang, Xue-Hong; Liu, Jie; Zhu, Yi-Nian; Gu, Chen

    2014-01-01

    As a low-cost treatment technology for effluent, the constructed wetlands can be applied to remove the heavy metals from wastewater. Leersia hexandra Swartz is a metal-accumulating hygrophyte with great potential to remove heavy metal from water. In this study, two pilot-scale constructed wetlands planted with L. hexandra (CWL) were set up in greenhouse to treat electroplating wastewater containing Cr, Cu and Ni. The treatment performance of CWL under different hydraulic loading rates (HLR) and initial metal concentrations were also evaluated. The results showed that CWL significantly reduced the concentrations of Cr, Cu and Ni in wastewater by 84.4%, 97.1% and 94.3%, respectively. High HLR decreased the removal efficiencies of Cr, Cu and Ni; however, the heavy metal concentrations in effluent met Emission Standard of Pollutants for Electroplating in China (ESPE) at HLR less than 0.3 m3/m2 d. For the influent of 5 mg/L Cr, 10 mg/L Cu and 8 mg/L Ni, effluent concentrations were below maximum allowable concentrations in ESPE, indicating that the removal of Cr, Cu and Ni by CWL was feasible at considerably high influent metal concentrations. Mass balance showed that the primary sink for the retention of contaminants within the constructed wetland system was the sediment, which accounted for 59.5%, 83.5%, and 73.9% of the Cr, Cu and Ni, respectively. The data from the pilot wetlands support the view that CWL could be used to successfully remove Cr, Cu and Ni from electroplating wastewater.

  14. Plant Rhizosphere Effects on Metal Mobilization and Transport

    SciTech Connect

    Fan, Teresa W.-M; Crowley, David; Higashi, Richard M.

    1999-06-01

    A mechanistic understanding of mobilization or immobilization of nutrient and pollutant metal ions by plants is largely lacking. It begins with a lack of knowledge on the chemical nature of rhizosphere components that are reactive with metal ions. This fundamental knowledge is critical to the design and implementation of phytoremediation for metal-contaminated DOE sites. Therefore, the objectives of this project include (1) To obtain a comprehensive composition of major organic components in plant root exudates as a function of different metal ions and plant species; (2) To examine plant metabolic response(s) to these metal ion treatments, with emphasis on production of metal reactive compounds; (3) To investigate the effect(s) of soil microbial (e.g. mycorrhizae) association on (1) and (2).

  15. Effect of latitude on flavonoid biosynthesis in plants.

    PubMed

    Jaakola, Laura; Hohtola, Anja

    2010-08-01

    The growth conditions in different latitudes vary markedly with season, day length, light quality and temperature. Many plant species have adapted well to the distinct environments through different strategies, one of which is the production of additional secondary metabolites. Flavonoids are a widely spread group of plant secondary metabolites that are involved in many crucial functions of plants. Our understanding of the biosynthesis, occurrence and function of flavonoids has increased rapidly in recent decades. Numerous studies have been published on the influence of environmental factors on the biosynthesis of flavonoids. However, extensive long-term studies that examine the effect of the characteristics of northern climates on flavonoid biosynthesis are still scarce. This review focuses on the current knowledge about the effect of light intensity, photoperiod and temperature on the gene-environment interaction related to flavonoid biosynthesis in plants.

  16. Ecological effects of pipeline construction through deciduous forested wetlands, Midland County, Michigan. Topical report, October 1990--August 1992

    SciTech Connect

    Rastorfer, J.R.; Van Dyke, G.D.; Zellmer, S.D.; Wilkey, P.L.

    1995-04-01

    This study is designed to record vegetational changes induced by the construction of a large-diameter gas pipeline through deciduous forested wetlands. Two second-growth wetland sites mapped Lenawee soils were selected in Midland County, Michigan: Site 1, a younger stand subjected to recent selective logging, and Site 2, a more mature stand. The collection of ecological data to analyze plant succession on the right-of-way (ROW) and the effects of the developing ROW plant communities on adjacent forest communities was initiated in 1989. Cover class estimates were made for understory and ROW plant species on the basis of 1 {times} 1{minus}m quadrats. Individual stem diameters and species counts were recorded for overstory plants in 10{minus}m quadrats. Although long-term studies have not been completed, firm baseline data were established for comparative analyses with future sampling. Current data indicate that vegetation became well-established on the ROW within one year and subsequently increased in coverage. About 65% of the species were wetland indicators, and the dominants included seeded and natural invading species; nevertheless, some elements of the original flora regenerated and persist. The plants of the ecotone understories of both sites changed from their original composition as a result of the installation of the gas pipeline. Although some forest species persist at both sites, the ecotone of Site I was influenced more by the seeded species, whereas the natural invaders were more important at Site 2.

  17. Distribution of malarial parasites: effect of gender of construction workers.

    PubMed

    Venugopalan, P P; Shenoy, D U; Kamath, A; Rajeev, A

    1997-03-01

    The city of Mangalore in South India was having increasing number of malaria cases from 1990. Concerned over the import of cases through migrant construction workers, a screening was done among them using clinical and parasitological methods. This demonstrated 6.28% slide positivity rate with statistically insignificant difference in prevalence of infection between males and females. There were many asymptomatic individuals reporting positive only on peripheral smear examination. Yet, clinical symptoms like fever were found to have good predictive value on logistic regression. It was more so with the P. falciparum which is a relatively new entrant to Mangalore.

  18. Psychological Processes Underlying Cultivation Effects: Further Tests of Construct Accessibility.

    ERIC Educational Resources Information Center

    Shrum, L. J.

    1996-01-01

    Describes a study that tested whether the accessibility of information in memory mediates the cultivation effect (the effect of television viewing on social perceptions), consistent with the availability heuristic. Shows that heavy viewers gave higher frequency estimates (cultivation effect) and responded faster (accessibility effect) than did…

  19. Effectiveness of mitigation measures with constructed forested wetlands in Maryland

    USGS Publications Warehouse

    Perry, M.C.

    1997-01-01

    Intensive research on six constructed forested wetlands in Central Maryland was conducted in 1993-1996 to determine success of these habitats as functional forested wetlands for wildlife. Areas studied ranged in size from 2 to 35 acres and were constructed by private companies under contract with three mitigation agencies. Adjacent natural forested wetlands were used as reference sites where similar data were collected. Based on data from the first four years of this study it appears that it will take 35-50 years before these areas have forested wetland vegetation and wildlife similar to that found on mature forested wetlands. This long-time period is based on the high mortality and slow growth of nursery-stock trees and shrubs transplanted on the areas. Mortality and slow growth resulted mostly from excessive surface water on the sites. The level of ground water did not appear to be a factor in regard to transplant mortality. Green ash was the woody transplant species that had the least mortality. Sampling of vegetative ground cover with one-meter square quadrats showed the predominance of grasses and herbs. [abridged abstract

  20. Antioxidant activity and protecting health effects of common medicinal plants.

    PubMed

    Škrovánková, Soňa; Mišurcová, Ladislava; Machů, Ludmila

    2012-01-01

    Medicinal plants are traditionally used in folk medicine as natural healing remedies with therapeutic effects such as prevention of cardiovascular diseases, inflammation disorders, or reducing the risk of cancer. In addition, pharmacological industry utilizes medicinal plants due to the presence of active chemical substances as agents for drug synthesis. They are valuable also for food and cosmetic industry as additives, due to their preservative effects because of the presence of antioxidants and antimicrobial constituents. To commonly used medicinal plants with antioxidant activity known worldwide belong plants from several families, especially Lamiaceae (rosemary, sage, oregano, marjoram, basil, thyme, mints, balm), Apiaceae (cumin, fennel, caraway), and Zingiberaceae (turmeric, ginger). The antioxidant properties of medicinal plants depend on the plant, its variety, environmental conditions, climatic and seasonal variations, geographical regions of growth, degree of ripeness, growing practices, and many other factors such as postharvest treatment and processing. In addition, composition and concentration of present antioxidants, such as phenolic compounds, are related to antioxidant effect. For appropriate determination of antioxidant capacity, the extraction technique, its conditions, solvent used, and particular assay methodology are important. PMID:23034115

  1. Antioxidant activity and protecting health effects of common medicinal plants.

    PubMed

    Škrovánková, Soňa; Mišurcová, Ladislava; Machů, Ludmila

    2012-01-01

    Medicinal plants are traditionally used in folk medicine as natural healing remedies with therapeutic effects such as prevention of cardiovascular diseases, inflammation disorders, or reducing the risk of cancer. In addition, pharmacological industry utilizes medicinal plants due to the presence of active chemical substances as agents for drug synthesis. They are valuable also for food and cosmetic industry as additives, due to their preservative effects because of the presence of antioxidants and antimicrobial constituents. To commonly used medicinal plants with antioxidant activity known worldwide belong plants from several families, especially Lamiaceae (rosemary, sage, oregano, marjoram, basil, thyme, mints, balm), Apiaceae (cumin, fennel, caraway), and Zingiberaceae (turmeric, ginger). The antioxidant properties of medicinal plants depend on the plant, its variety, environmental conditions, climatic and seasonal variations, geographical regions of growth, degree of ripeness, growing practices, and many other factors such as postharvest treatment and processing. In addition, composition and concentration of present antioxidants, such as phenolic compounds, are related to antioxidant effect. For appropriate determination of antioxidant capacity, the extraction technique, its conditions, solvent used, and particular assay methodology are important.

  2. Effects of air current speed on gas exchange in plant leaves and plant canopies

    NASA Astrophysics Data System (ADS)

    Kitaya, Y.; Tsuruyama, J.; Shibuya, T.; Yoshida, M.; Kiyota, M.

    To obtain basic data on adequate air circulation to enhance plant growth in a closed plant culture system in a controlled ecological life support system (CELSS), an investigation was made of the effects of the air current speed ranging from 0.01 to 1.0 m s-1 on photosynthesis and transpiration in sweetpotato leaves and photosynthesis in tomato seedlings canopies. The gas exchange rates in leaves and canopies were determined by using a chamber method with an infrared gas analyzer. The net photosynthetic rate and the transpiration rate increased significantly as the air current speeds increased from 0.01 to 0.2 m s-1. The transpiration rate increased gradually at air current speeds ranging from 0.2 to 1.0 m s-1 while the net photosynthetic rate was almost constant at air current speeds ranging from 0.5 to 1.0 m s-1. The increase in the net photosynthetic and transpiration rates were strongly dependent on decreased boundary-layer resistances against gas diffusion. The net photosynthetic rate of the plant canopy was doubled by an increased air current speed from 0.1 to 1.0 m s-1 above the plant canopy. The results demonstrate the importance of air movement around plants for enhancing the gas exchange in the leaf, especially in plant canopies in the CELSS.

  3. Effects of recycled FGD liner material on water quality and macrophytes of constructed wetlands: a mesocosm experiment.

    PubMed

    Ahn, C; Mitsch, W J; Wolfe, W E

    2001-03-01

    We investigated the use of flue-gas-desulfurization (FGD) by-products from electric power plant wet scrubbers as liners in wetlands constructed to improve water quality. Mesocosm experiments were conducted over two consecutive growing seasons with different phosphorus loadings. Wetland mesocosms using FGD liners retained more total and soluble reactive phosphorus, with lower concentrations in the leachate (first year) and higher concentrations in the surface water (second year). Leachate was higher in conductivity (second year) and pH (both years) in lined mesocosms. Surface outflow did not reveal any significant difference in physicochemical characteristics between lined and unlined mesocosms. There was no significant difference in total biomass production of wetland plants between lined and unlined mesocosms although lower average stem lengths and fewer stems bearing flowers were observed in mesocosms with FGD liners. Potentially phytotoxic boron was significantly higher in the belowground biomass of plants grown in lined mesocosms with low phosphorus loading. A larger-scale, long-term wetland experiment close to full scale is recommended from this two-year mesocosm study to better predict the potentially positive and negative effects of using FGD by-products in constructed wetlands.

  4. Complex effects of fertilization on plant and herbivore performance in the presence of a plant competitor and activated carbon.

    PubMed

    Mahdavi-Arab, Nafiseh; Meyer, Sebastian T; Mehrparvar, Mohsen; Weisser, Wolfgang W

    2014-01-01

    Plant-herbivore interactions are influenced by host plant quality which in turn is affected by plant growth conditions. Competition is the major biotic and nutrient availability a major abiotic component of a plant's growth environment. Yet, surprisingly few studies have investigated impacts of competition and nutrient availability on herbivore performance and reciprocal herbivore effects on plants. We studied growth of the specialist aphid, Macrosiphoniella tanacetaria, and its host plant tansy, Tanacetum vulgare, under experimental addition of inorganic and organic fertilizer crossed with competition by goldenrod, Solidago canadensis. Because of evidence that competition by goldenrod is mediated by allelopathic compounds, we also added a treatment with activated carbon. Results showed that fertilization increased, and competition with goldenrod decreased, plant biomass, but this was likely mediated by resource competition. There was no evidence from the activated carbon treatment that allelopathy played a role which instead had a fertilizing effect. Aphid performance increased with higher plant biomass and depended on plant growth conditions, with fertilization and AC increasing, and plant competition decreasing aphid numbers. Feedbacks of aphids on plant performance interacted with plant growth conditions in complex ways depending on the relative magnitude of the effects on plant biomass and aphid numbers. In the basic fertilization treatment, tansy plants profited from increased nutrient availability by accumulating more biomass than they lost due to an increased number of aphids under fertilization. When adding additional fertilizer, aphid numbers increased so high that tansy plants suffered and showed reduced biomass compared with controls without aphids. Thus, the ecological cost of an infestation with aphids depends on the balance of effects of growth conditions on plant and herbivore performance. These results emphasize the importance to investigate both

  5. Complex effects of fertilization on plant and herbivore performance in the presence of a plant competitor and activated carbon.

    PubMed

    Mahdavi-Arab, Nafiseh; Meyer, Sebastian T; Mehrparvar, Mohsen; Weisser, Wolfgang W

    2014-01-01

    Plant-herbivore interactions are influenced by host plant quality which in turn is affected by plant growth conditions. Competition is the major biotic and nutrient availability a major abiotic component of a plant's growth environment. Yet, surprisingly few studies have investigated impacts of competition and nutrient availability on herbivore performance and reciprocal herbivore effects on plants. We studied growth of the specialist aphid, Macrosiphoniella tanacetaria, and its host plant tansy, Tanacetum vulgare, under experimental addition of inorganic and organic fertilizer crossed with competition by goldenrod, Solidago canadensis. Because of evidence that competition by goldenrod is mediated by allelopathic compounds, we also added a treatment with activated carbon. Results showed that fertilization increased, and competition with goldenrod decreased, plant biomass, but this was likely mediated by resource competition. There was no evidence from the activated carbon treatment that allelopathy played a role which instead had a fertilizing effect. Aphid performance increased with higher plant biomass and depended on plant growth conditions, with fertilization and AC increasing, and plant competition decreasing aphid numbers. Feedbacks of aphids on plant performance interacted with plant growth conditions in complex ways depending on the relative magnitude of the effects on plant biomass and aphid numbers. In the basic fertilization treatment, tansy plants profited from increased nutrient availability by accumulating more biomass than they lost due to an increased number of aphids under fertilization. When adding additional fertilizer, aphid numbers increased so high that tansy plants suffered and showed reduced biomass compared with controls without aphids. Thus, the ecological cost of an infestation with aphids depends on the balance of effects of growth conditions on plant and herbivore performance. These results emphasize the importance to investigate both

  6. The effects of psammophilous plants on sand dune dynamics

    NASA Astrophysics Data System (ADS)

    Bel, Golan; Ashkenazy, Yosef

    2014-07-01

    Mathematical models of sand dune dynamics have considered different types of sand dune cover. However, despite the important role of psammophilous plants (plants that flourish in moving-sand environments) in dune dynamics, the incorporation of their effects into mathematical models of sand dunes remains a challenging task. Here we propose a nonlinear physical model for the role of psammophilous plants in the stabilization and destabilization of sand dunes. There are two main mechanisms by which the wind affects these plants: (i) sand drift results in the burial and exposure of plants, a process that is known to result in an enhanced growth rate, and (ii) strong winds remove shoots and rhizomes and seed them in nearby locations, enhancing their growth rate. Our model describes the temporal evolution of the fractions of surface cover of regular vegetation, biogenic soil crust, and psammophilous plants. The latter reach their optimal growth under either (i) specific sand drift or (ii) specific wind power. The model exhibits complex bifurcation diagrams and dynamics, which explain observed phenomena, and it predicts new dune stabilization scenarios. Depending on the climatological conditions, it is possible to obtain one, two, or, predicted here for the first time, three stable dune states. Our model shows that the development of the different cover types depends on the precipitation rate and the wind power and that the psammophilous plants are not always the first to grow and stabilize the dunes.

  7. Effects of Ozone on Gas Exchange in Invasive Forest Plants.

    NASA Astrophysics Data System (ADS)

    Elton, E. E.

    2006-12-01

    Evaluations of invasive plant biology have failed to investigate the relationship between leaf structure and effects of ozone among closely related native and non-native plants. When exposed to toxic pollutants plants with lower stomatal density and lower stomatal conductance might experience reduced exposure and consequently be more competitive. To test for systematic differences between invasive and native species, experiments assessed the stomatal density and stomatal conductance of nine non-native invasive species and thirteen native species. Field sites, used for forest surveys, centered on three urban areas including sites with differing ozone levels (low 0-60 ppb, medium 80-99 ppb, high 111-125+ ppb). Three sites were selected within each of the three urban areas, and surveys were taken at each of the nine sites determining the native and non-native plant composition. The low level sites had greater densities of native plants than the high ozone level sites. Leaf impressions revealed a significantly higher (t = 14.13, p < 0.0001) stomatal density for the natives, and a LI-COR 1600 showed significantly higher (Fndf,ddf = 12.88, p = 0.0004) stomatal conductance for native plants. Dissimilar gas-exchange capacities are likely to be linked to the observed differences in plant composition among study sites. The importance of addressing air and biotic pollution grows every year as human health, agriculture, and ecosystem function are negatively affected in new areas.

  8. The effects of tannery wastewater on the development of different plant species and chromium accumulation in Phragmites australis.

    PubMed

    Calheiros, Cristina S C; Rangel, António O S S; Castro, Paula M L

    2008-10-01

    Toxicity tests were performed to assess the effect of tannery wastewater with different treatment levels on two wetland plants, Phragmites australis and Typha latifolia, which are frequently used in constructed wetlands (CWs) for water treatment, and thus deepen the knowledge on their capacity to withstand the application of industrial wastewater. Trifolium pratense, a plant generally used as an indicator in toxicity tests, was included as a control. End points measured were germination percentage, shoot length, root elongation, and biomass growth of the plants. When tannery effluent, with a low treatment level, was supplied to the wetland plants germination occurred even at effluent concentrations of 100%, whereas germination of T. pratense was completely inhibited, almost invariably, at effluent concentration of 50%. Higher germination levels were achieved when the plants were exposed to effluent originating from the outlet of constructed wetland pilot units, allowing germination of all tested plants, indicating a significant decrease in its toxicity level. Experiments conducted with the same plants using different growing substrata as the germination matrix, namely expanded clay aggregates (Filtralite MR 3-8 and Filtralite NR 3-8) and two types of sand (fine gravel and standard sand) have shown that higher germination levels were achieved in standard sand and that P. australis was the plant species showing higher germination in all cases, reinforcing the robustness of this plant to environmental stress. The phytoextraction potential of P. australis, was evaluated by subjecting the plant to tannery wastewater supplemented with 50 and 150 mg Cr/L. After 6 weeks of exposure, levels up to 4825, 883, and 627 mg Cr/kg were found in the rhizome, shoot, and leaves, respectively, although phytotoxic signs in the plant were evident. This plant might not be considered a chromium hyperacumulator, but the potential to extract and accumulate this metal on its rhizomes is high.

  9. Spatial distribution of organic pollutants in industrial construction and demolition waste and their mutual interaction on an abandoned pesticide manufacturing plant.

    PubMed

    Huang, Sheng; Zhao, Xin; Sun, Yanqiu; Ma, Jianli; Gao, Xiaofeng; Xie, Tian; Xu, Dongsheng; Yu, Yi; Zhao, Youcai

    2016-04-01

    A comprehensive field investigation of organic pollutants was examined in industrial construction and demolition waste (ICDW) inside an abandoned pesticide manufacturing plant. Concentrations of eight types of pesticides, a metabolite and two intermediates were studied. The ICDW was under severe and long-term contamination by organophosphorus, intermediates and pyrethroid pesticide with mean concentrations of 23,429, 3538 and 179.4 mg kg(-1), respectively. FT-IR analysis suggested that physical absorption and chemical bonding were their mutual interaction forms. Patterns of total pesticide spatial distribution showed good correlations with manufacturing processes spreading all over the plant both in enclosed workshops and in residues randomly dumped outside, while bricks and coatings were the most vulnerable to pollutants. Ultimately the fate of the OPPs was diversified as the immersion of ICDW in water largely transferred the pollutants into aquatic systems while exposure outside did not largely lead to pesticide degradation. The adoption of centralized collections for the disposal of wastes could only eliminate part of the contaminated ICDW, probably due to lack of knowledge and criteria. Correlation matrix and cluster analysis indicated that regulated disposal and management of polluted ICDW was effective, thus presenting the requirement for its appropriate disposal. PMID:26972868

  10. Space radiation effects on plant and mammalian cells

    NASA Astrophysics Data System (ADS)

    Arena, C.; De Micco, V.; Macaeva, E.; Quintens, R.

    2014-11-01

    The study of the effects of ionizing radiation on organisms is related to different research aims. The current review emphasizes the studies on the effects of different doses of sparsely and densely ionizing radiation on living organisms, with the final purpose of highlighting specific and common effects of space radiation in mammals and plants. This topic is extremely relevant in the context of radiation protection from space environment. The response of different organisms to ionizing radiation depends on the radiation quality/dose and/or the intrinsic characteristics of the living system. Macromolecules, in particular DNA, are the critical targets of radiation, even if there is a strong difference between damages encountered by plant and mammalian cells. The differences in structure and metabolism between the two cell types are responsible for the higher resistance of the plant cell compared with its animal counterpart. In this review, we report some recent findings from studies performed in Space or on Earth, simulating space-like levels of radiation with ground-based facilities, to understand the effect of ionizing radiation on mammalian and plant cells. In particular, our attention is focused on genetic alterations and repair mechanisms in mammalian cells and on structures and mechanisms conferring radioresistance to plant cells.

  11. Two poplar-associated bacterial isolates induce additive favorable responses in a constructed plant-microbiome system

    DOE PAGES

    Jawdy, Sara S.; Gunter, Lee E.; Engle, Nancy L.; Yang, Zamin Koo; Lu, Tse-Yuan S.; Tschaplinski, Timothy J.; Tuskan, Gerald A.; Doktycz, Mitchel John; Pelletier, Dale A.; Weston, David J.; et al

    2016-04-26

    Here, the biological function of the plant-microbiome system is the result of contributions from the host plant and microbiome members. In this work we study the function of a simplified community consisting of Pseudomonas and Burkholderia bacterial strains isolated from Populus hosts and inoculated on axenic Populus cutting in controlled laboratory conditions. Inoculation individually with either bacterial isolate increased root growth relative to uninoculated controls. Root area, photosynthetic efficiency, gene expression and metabolite expression data in individual and dual inoculated treatments indicate that the effects of these bacteria are unique and additive, suggesting that the function of a microbiome communitymore » may be predicted from the additive functions of the individual members.« less

  12. Characterizing variation in mycorrhiza effect among diverse plant varieties.

    PubMed

    Sawers, Ruairidh J H; Gebreselassie, Mesfin N; Janos, David P; Paszkowski, Uta

    2010-03-01

    Exploitation of arbuscular mycorrhizal fungi may be an important approach for development of reduced-input agriculture. We discuss the use of linear models to analyze variation in mycorrhiza response among diverse plant varieties in order to assess the value of mycorrhizas. Our approach allows elimination of variation linked to differences in plant performance in the absence of mycorrhizas and the selection of plant lines that might harbor genetic variation of use to improve the mycorrhizal symbiosis in agriculture. We illustrate our approach by applying it to previously published and to novel data. We suggest that in dealing with a relative trait such as mycorrhiza effect, the choice of measure used to quantify the trait greatly affects interpretation. In the plant populations under consideration, we find evidence for a greater potential to increase mycorrhiza benefit than previously suggested.

  13. Investigating the effectiveness of response strategies for vulnerabilities to corruption in the chinese public construction sector.

    PubMed

    Shan, Ming; Chan, Albert P C; Le, Yun; Hu, Yi

    2015-06-01

    Response strategy is a key for preventing widespread corruption vulnerabilities in the public construction sector. Although several studies have been devoted to this area, the effectiveness of response strategies has seldom been evaluated in China. This study aims to fill this gap by investigating the effectiveness of response strategies for corruption vulnerabilities through a survey in the Chinese public construction sector. Survey data obtained from selected experts involved in the Chinese public construction sector were analyzed by factor analysis and partial least squares-structural equation modeling. Analysis results showed that four response strategies of leadership, rules and regulations, training, and sanctions, only achieved an acceptable level in preventing corruption vulnerabilities in the Chinese public construction sector. This study contributes to knowledge by improving the understanding of the effectiveness of response strategies for corruption vulnerabilities in the public construction sector of developing countries. PMID:24894336

  14. Investigating the effectiveness of response strategies for vulnerabilities to corruption in the chinese public construction sector.

    PubMed

    Shan, Ming; Chan, Albert P C; Le, Yun; Hu, Yi

    2015-06-01

    Response strategy is a key for preventing widespread corruption vulnerabilities in the public construction sector. Although several studies have been devoted to this area, the effectiveness of response strategies has seldom been evaluated in China. This study aims to fill this gap by investigating the effectiveness of response strategies for corruption vulnerabilities through a survey in the Chinese public construction sector. Survey data obtained from selected experts involved in the Chinese public construction sector were analyzed by factor analysis and partial least squares-structural equation modeling. Analysis results showed that four response strategies of leadership, rules and regulations, training, and sanctions, only achieved an acceptable level in preventing corruption vulnerabilities in the Chinese public construction sector. This study contributes to knowledge by improving the understanding of the effectiveness of response strategies for corruption vulnerabilities in the public construction sector of developing countries.

  15. Antifertility screening of plants. 3. Effect of six indigenous plants on early pregnancy in albino rats.

    PubMed

    Vohora, S B; Garg, S K; Chaudhury, R R

    1969-05-01

    The effect of 6 indigenous plants on early pregnancy in albino rats was tested by a screening procedure standardized in this laboratory. Pe troleum ether, alcoholic, and aqueous extracts of each plant were tested for antifertilizing, antizygotic, blastocystotoxic, antiimplantation, and early abortifacient activity. The aqueous extract of Ocimum sanctum Linn. leaves and alcoholic extract of Polygonum hydropiper Linn. roots showed encouraging results while the extracts of Abroma augusta Linn. roots, Calotropis gigantea Linn. flowers and leaves, Michaelia champaka Linn. unripe fruit, and Plumbago rosea Linn. roots did not show any antiimplantation activity. None of the rats delivered to experimental rats showed evidence of teratogenicity up to the age of 1 month. PMID:5820437

  16. Antifertility screening of plants. 3. Effect of six indigenous plants on early pregnancy in albino rats.

    PubMed

    Vohora, S B; Garg, S K; Chaudhury, R R

    1969-05-01

    The effect of 6 indigenous plants on early pregnancy in albino rats was tested by a screening procedure standardized in this laboratory. Pe troleum ether, alcoholic, and aqueous extracts of each plant were tested for antifertilizing, antizygotic, blastocystotoxic, antiimplantation, and early abortifacient activity. The aqueous extract of Ocimum sanctum Linn. leaves and alcoholic extract of Polygonum hydropiper Linn. roots showed encouraging results while the extracts of Abroma augusta Linn. roots, Calotropis gigantea Linn. flowers and leaves, Michaelia champaka Linn. unripe fruit, and Plumbago rosea Linn. roots did not show any antiimplantation activity. None of the rats delivered to experimental rats showed evidence of teratogenicity up to the age of 1 month.

  17. Weldon Spring quarry construction staging area and water treatment plant site remedial action characterization report for the Weldon Spring Site Remedial Action Project, Weldon Spring, Missouri

    SciTech Connect

    Not Available

    1991-09-01

    The quarry construction staging area (QCSA) and water treatment plant (WTP) are located in the areas that border the western edge of the Weldon Spring quarry (WSQ). These facilities were constructed to support bulk waste removal from the WSQ. This area was contaminated with U-238, Ra-226, and Th-230 and was remediated prior to construction in order to allow release of the area for use without radiological restrictions. This report documents the methods of characterization, the remediation activities, and the post remedial action sampling methods and analytical results. 4 refs., 6 figs., 4 tabs.

  18. Effects of Delayed Constructed-Response Identity Matching on Spelling of Dictated Words

    ERIC Educational Resources Information Center

    Hanna, Elenice S.; de Souza, Deisy G.; de Rose, Julio C.; Fonseca, Monica

    2004-01-01

    We studied the effects of delayed constructed-response identity marching on spelling with 6 first graders with histories of school failure. After training, the children learned to spell words to dictation and their cursive writing improved. These results replicate studies showing that delayed constructed-response matching establishes spelling. For…

  19. Effects of Evaluative vs. Co-Constructive Interactions on Learning in Physics

    ERIC Educational Resources Information Center

    Toczek, Marie-Christine; Morge, Ludovic

    2009-01-01

    We conducted an experimental study to assess the effects of two physics-learning situations that differed in the type of teacher-student interactions that took place: evaluative or co-constructive. As found in various studies on physics teaching and social psychology, the results showed that co-constructive interactions generated a more effective…

  20. Molybdenum(VI) removal by using constructed wetlands with different filter media and plants.

    PubMed

    Lian, J J; Xu, S G; Zhang, Y M; Han, C W

    2013-01-01

    The efficacy and capacity of vertical-flow wetland filters on molybdenum (Mo) removal from wastewater was examined, employing reed (Phragmites australis) and cattail (Typha latifolia) as well as different adsorption granular media. Humus, cinder, modified cinder, as well as pyrite were used as filter media. A synthetic effluent with different concentrations of Mo(VI) at different hydraulic retention times was used for simulating Mo leached mine wastewater. Laboratory experiments showed that the equilibrium adsorption data were in agreement with the Langmuir isotherm model, and the maximum Mo(VI) adsorption capacities of modified cinder and pyrite were 10.01 and 6.25 mg/g, respectively. Mo(VI) removal in F5 (combination substrates of pyrite and cinder) was found to be more stable and effective than that of F1 (conventional gravel and soil filter media) during the 14-week experiment. Most of the Mo(VI) was retained in the 10-20 cm of the substrate, and adsorbed by the modified cinder and pyrite. The largest fraction of Mo(VI) retained was the water-soluble fraction on the surface of the pyrite. Cattail was more suitable for Mo(VI) absorption than reed, but the bioaccumulation accounted for a very small portion of the total removal.

  1. Effect of spray aeration on organics and nitrogen removal in vertical subsurface flow constructed wetland.

    PubMed

    Ding, Yi; Wang, Wei; Song, Xin-Shan; Wang, Gang; Wang, Yu-Hui

    2014-12-01

    The objective of present study was to assess the simultaneous removal of organics and nitrogen by four lab-scale vertical subsurface flow constructed wetlands (V-SFCWs). The emergent plants employed were Canna indica. Five-month experiments showed that the planted and aerated system largely reduced the COD by 95%, NH4 by 88% and total inorganic nitrogen (TIN) by 83%. It outperformed the unplanted or simple aerated system and was much better than non-aerated system. The study provided a strong evidence to support widespread research and application of spray aeration as a low-cost and energy-efficient aeration technology in V-SFCWs. PMID:25259785

  2. Effect of spray aeration on organics and nitrogen removal in vertical subsurface flow constructed wetland.

    PubMed

    Ding, Yi; Wang, Wei; Song, Xin-Shan; Wang, Gang; Wang, Yu-Hui

    2014-12-01

    The objective of present study was to assess the simultaneous removal of organics and nitrogen by four lab-scale vertical subsurface flow constructed wetlands (V-SFCWs). The emergent plants employed were Canna indica. Five-month experiments showed that the planted and aerated system largely reduced the COD by 95%, NH4 by 88% and total inorganic nitrogen (TIN) by 83%. It outperformed the unplanted or simple aerated system and was much better than non-aerated system. The study provided a strong evidence to support widespread research and application of spray aeration as a low-cost and energy-efficient aeration technology in V-SFCWs.

  3. Complex Effects of Fertilization on Plant and Herbivore Performance in the Presence of a Plant Competitor and Activated Carbon

    PubMed Central

    Mahdavi-Arab, Nafiseh; Meyer, Sebastian T.; Mehrparvar, Mohsen; Weisser, Wolfgang W.

    2014-01-01

    Plant-herbivore interactions are influenced by host plant quality which in turn is affected by plant growth conditions. Competition is the major biotic and nutrient availability a major abiotic component of a plant’s growth environment. Yet, surprisingly few studies have investigated impacts of competition and nutrient availability on herbivore performance and reciprocal herbivore effects on plants. We studied growth of the specialist aphid, Macrosiphoniella tanacetaria, and its host plant tansy, Tanacetum vulgare, under experimental addition of inorganic and organic fertilizer crossed with competition by goldenrod, Solidago canadensis. Because of evidence that competition by goldenrod is mediated by allelopathic compounds, we also added a treatment with activated carbon. Results showed that fertilization increased, and competition with goldenrod decreased, plant biomass, but this was likely mediated by resource competition. There was no evidence from the activated carbon treatment that allelopathy played a role which instead had a fertilizing effect. Aphid performance increased with higher plant biomass and depended on plant growth conditions, with fertilization and AC increasing, and plant competition decreasing aphid numbers. Feedbacks of aphids on plant performance interacted with plant growth conditions in complex ways depending on the relative magnitude of the effects on plant biomass and aphid numbers. In the basic fertilization treatment, tansy plants profited from increased nutrient availability by accumulating more biomass than they lost due to an increased number of aphids under fertilization. When adding additional fertilizer, aphid numbers increased so high that tansy plants suffered and showed reduced biomass compared with controls without aphids. Thus, the ecological cost of an infestation with aphids depends on the balance of effects of growth conditions on plant and herbivore performance. These results emphasize the importance to investigate both

  4. Effects of Traditional Lecture versus Teacher-Constructed and Student-Constructed Self-Teaching Instructional Resources on Short-Term Science Achievement and Attitudes.

    ERIC Educational Resources Information Center

    McManus, Deborah O'Connell; Dunn, Rita; Denig, Stephen J.

    2003-01-01

    Compares the effects of three different teaching methods: (1) traditional instruction through listening to a lecture, reading, and participating in discussion; (2) instruction with teacher-constructed self-teaching resources; and (3) instruction with student-constructed self-teaching resources. Determines their effectiveness and the time required…

  5. Fermions on the worldsheet of effective strings via coset construction

    NASA Astrophysics Data System (ADS)

    Mohsen, Ali

    2016-05-01

    In this paper the detailed Coleman-Callan-Wess-Zumino procedure for introducing fermions on the world sheet of a string propagating in flat space-time is presented. The theory of nonlinear realizations is used to derive the transformation as well as the interactions of fermionic matter fields under arbitrary spinorial representations of the unbroken subgroup. This demonstrates that even for nonsupersymmetric spinors, the interactions are still severely restricted by the nonlinearly realized symmetry. We also explain how supersymmetric models provide an example for this construction with Goldstinos as matter fields, and how one can use the κ -symmetry of the Green Schwarz action in particular, to verify this nonlinear transformation for a specific matter field representation. We finally restrict the target space dimension without reference to supersymmetry, but rather by imposing one-loop integrability on a fermionic string that nonlinearly realizes Poincare symmetry. This singles out the critical dimension D =10 for heterotic, Green-Schwarz and Ramond-Neveu-Schwarz supersymmetric strings.

  6. Trypanocidal and cytotoxic effects of 30 Ethiopian medicinal plants.

    PubMed

    Nibret, Endalkachew; Wink, Michael

    2011-01-01

    Trypanocidal and cytotoxic effects of traditionally used medicinal plants of Ethiopia were evaluated. A total of 60 crude plant extracts were prepared from 30 plant species using CH2Cl2 and MeOH. Effect upon cell proliferation by the extracts, for both bloodstream forms of Trypanosoma brucei brucei and human leukaemia HL-60 cells, was assessed using resazurin as vital stain. Of all CH2Cl2 and MeOH extracts evaluated against the trypanosomes, the CH2Cl2 extracts from five plants showed trypanocidal activity with an IC50 value below 20 microg/mL: Dovyalis abyssinica (Flacourtiaceae), IC50 = 1.4 microg/mL; Albizia schimperiana (Fabaceae), IC50 = 7.2 microg/mL; Ocimum urticifolium (Lamiaceae), IC50 = 14.0 microg/mL; Acokanthera schimperi (Apocynaceae), IC50 = 16.6 microg/mL; and Chenopodium ambrosioides (Chenopodiaceae), IC50 = 17.1 microg/mL. A pronounced and selective killing of trypanosomes with minimal toxic effect on human cells was exhibited by Dovyalis abyssinica (CH2Cl2 extract, SI = 125.0; MeOH extract, SI = 57.7) followed by Albizia schimperiana (CH2Cl2 extract, SI = 31.3) and Ocimum urticifolium (MeOH extract, SI = 16.0). In conclusion, the screening of 30 Ethiopian medicinal plants identified three species with good antitrypanosomal activities and low toxicity towards human cells. Dovyalis abyssinica might be a promising candidate for phytotherapy of trypanosomiasis.

  7. Multifaceted effects of host plants on entomopathogenic nematodes.

    PubMed

    Hazir, Selcuk; Shapiro-Ilan, David I; Hazir, Canan; Leite, Luis G; Cakmak, Ibrahim; Olson, Dawn

    2016-03-01

    The success of parasites can be impacted by multi-trophic interactions. Tritrophic interactions have been observed in parasite-herbivore-host plant systems. Here we investigate aspects of multi-trophic interactions in a system involving an entomopathogenic nematode (EPN), its insect host, and host plant. Novel issues investigated include the impact of tritrophic interactions on nematode foraging behavior, the ability of EPNs to overcome negative tritrophic effects through genetic selection, and interactions with a fourth trophic level (nematode predators). We tested infectivity of the nematode, Steinernema riobrave, to corn earworm larvae (Helicoverpa zea) in three host plants, tobacco, eggplant and tomato. Tobacco reduced nematode virulence and reproduction relative to tomato and eggplant. However, successive selection (5 passages) overcame the deficiency; selected nematodes no longer exhibited reductions in phenotypic traits. Despite the loss in virulence and reproduction nematodes, first passage S. riobrave was more attracted to frass from insects fed tobacco than insects fed on other host plants. Therefore, we hypothesized the reduced virulence and reproduction in S. riobrave infecting tobacco fed insects would be based on a self-medicating tradeoff, such as deterring predation. We tested this hypothesis by assessing predatory success of the mite Sancassania polyphyllae and the springtail Sinella curviseta on nematodes reared on tobacco-fed larvae versus those fed on greater wax moth, Galleria mellonella, tomato fed larvae, or eggplant fed larvae. No advantage was observed in nematodes derived from tobacco fed larvae. In conclusion, our results indicated that insect-host plant diet has an important effect on nematode foraging, infectivity and reproduction. However, negative host plant effects, might be overcome through directed selection. We propose that host plant species should be considered when designing biocontrol programs using EPNs. PMID:26896698

  8. Effects of an exotic plant invasion on native understory plants in a tropical dry forest.

    PubMed

    Prasad, Ayesha E

    2010-06-01

    The dry forests of southern India, which are endangered tropical ecosystems and among the world's most important tiger (Panthera tigris) habitats, are extensively invaded by exotic plants. Yet, experimental studies exploring the impacts of these invasions on native plants in these forests are scarce. Consequently, little is known about associated implications for the long-term conservation of tigers and other biodiversity in these habitats. I studied the impacts of the exotic plant Lantana camara on understory vegetation in a dry-forest tiger habitat in southern India. I compared the richness, composition, and abundance of tree seedlings, herbs, and shrubs and the abundance of grass among plots in which Lantana was cleared or left standing. These plots were distributed across two blocks-livestock free and livestock grazed. Removal of Lantana had an immediate positive effect on herb-shrub richness in the livestock-free block, but had no effect on that of tree seedlings in either livestock block. Tree-seedling and herb-shrub composition differed significantly between Lantana treatment and livestock block, and Lantana removal significantly decreased survival of tree seedlings. Nevertheless, the absence of trees, in any stage between seedling and adult, indicates that Lantana may stall tree regeneration. Lantana removal decreased the abundance of all understory strata, probably because forage plants beneath Lantana are less accessible to herbivores, and plants in Lantana-free open plots experienced greater herbivory. Reduced access to forage in invaded habitats could negatively affect ungulate populations and ultimately compromise the ability of these forests to sustain prey-dependent large carnivores. Additional research focused on understanding and mitigating threats posed by exotic plants may be crucial to the long-term protection of these forests as viable tiger habitats.

  9. Effects of an exotic plant invasion on native understory plants in a tropical dry forest.

    PubMed

    Prasad, Ayesha E

    2010-06-01

    The dry forests of southern India, which are endangered tropical ecosystems and among the world's most important tiger (Panthera tigris) habitats, are extensively invaded by exotic plants. Yet, experimental studies exploring the impacts of these invasions on native plants in these forests are scarce. Consequently, little is known about associated implications for the long-term conservation of tigers and other biodiversity in these habitats. I studied the impacts of the exotic plant Lantana camara on understory vegetation in a dry-forest tiger habitat in southern India. I compared the richness, composition, and abundance of tree seedlings, herbs, and shrubs and the abundance of grass among plots in which Lantana was cleared or left standing. These plots were distributed across two blocks-livestock free and livestock grazed. Removal of Lantana had an immediate positive effect on herb-shrub richness in the livestock-free block, but had no effect on that of tree seedlings in either livestock block. Tree-seedling and herb-shrub composition differed significantly between Lantana treatment and livestock block, and Lantana removal significantly decreased survival of tree seedlings. Nevertheless, the absence of trees, in any stage between seedling and adult, indicates that Lantana may stall tree regeneration. Lantana removal decreased the abundance of all understory strata, probably because forage plants beneath Lantana are less accessible to herbivores, and plants in Lantana-free open plots experienced greater herbivory. Reduced access to forage in invaded habitats could negatively affect ungulate populations and ultimately compromise the ability of these forests to sustain prey-dependent large carnivores. Additional research focused on understanding and mitigating threats posed by exotic plants may be crucial to the long-term protection of these forests as viable tiger habitats. PMID:20067493

  10. [Effects of constructed wetlands on treating with nitrogen and phosphorus in wastewater from hoggery].

    PubMed

    Liao, Xind; Luo, Shiming

    2002-06-01

    Using plant species Vetiveria zizanioides (VCWS) and Cyperus alternifolius (CCWS) respectively, two constructed wetlands (CWS) with size of 1.0 m x 0.5 m x 0.8 m were established. The purifying function and its change pattern among different seasons, influent concentration and hydraulic retention time (HRT) of CWS on nitrogen and phosphorus in wastewater from a hoggery was studied throughout four seasons in the year. The results showed that the effects of HRT and wastewater concentration on the removal rate of NH3-N and S-PO4(3-) were obvious in both VCWS and CCWS. High removal rates of NH3-N and S-PO4(3-) were obtained in CCWS and VCWS in spring. Significant removal of TN in wastewater existed in CCWS and VCWS in autumn, while significant removal of TP in wastewater existed only in VCWS. The removal of TP or S-PO4(3-) against the HRT in CWS followed exponential function. The rates of P removal in winter and summer changed with the influent concentrations. Under the same HRT, the change of S-PO4(3-) concentrations in outflow against the influent concentration followed a linear relationship.

  11. Effect of aging on phosphorus speciation in surface deposit of a vertical flow constructed wetland.

    PubMed

    Kim, Boram; Gautier, Mathieu; Rivard, Camille; Sanglar, Corinne; Michel, Philippe; Gourdon, Rémy

    2015-04-21

    This study was conducted to determine phosphorus (P) species captured in a vertical-flow constructed wetland (VFCW) system combining a trickling filter followed by FeCl3 injection for phosphate coagulation. Suspended solids (SS) thus formed accumulated over time at the VFCW surface and transformed into a sludge deposit layer, which was shown to concentrate most of the P captured in the system. In order to investigate the effect of aging on P species, representative SS and sludge samples were taken from a wastewater treatment plant that had been in operation for 8 years and analyzed using P fractionation, solution (31)P NMR spectroscopy, and P and Fe K-edge XANES spectroscopy. A partial mineralization of organic matter was shown by comparing organic carbon contents of SS and sludge materials. Chemical fractionations combined with P and Fe K-edge XANES spectroscopy showed that P was predominantly bound to iron within both samples in the form of ferric phosphate, rather than adsorbed onto ferric oxyhydroxide. Calcium-bound P was more significantly observed in sludge than in SS, suggesting that aging induced the recombination of part of the organic and iron-bound P species into calcium-bound forms, as a possible consequence of the partial mineralization of organic matter. PMID:25710195

  12. Environments for Plants

    ERIC Educational Resources Information Center

    Mier, Robert; Poling, Donald

    1970-01-01

    Reviews some recent research on the effects of environment on plant growth. Also offers some how-to-do-it information on building low-cost, easy-to-construct greenhouses and growth chambers for school use. Bibliography. (LC)

  13. Which ornamental plant species effectively remove benzene from indoor air?

    NASA Astrophysics Data System (ADS)

    Liu, Yan-Ju; Mu, Yu-Jing; Zhu, Yong-Guan; Ding, Hui; Crystal Arens, Nan

    Phytoremediation—using plants to remove toxins—is an attractive and cost effective way to improve indoor air quality. This study screened ornamental plants for their ability to remove volatile organic compounds from air by fumigating 73 plant species with 150 ppb benzene, an important indoor air pollutant that poses a risk to human health. The 10 species found to be most effective at removing benzene from air were fumigated for two more days (8 h per day) to quantify their benzene removal capacity. Crassula portulacea, Hydrangea macrophylla, Cymbidium Golden Elf., Ficus microcarpa var. fuyuensis, Dendranthema morifolium, Citrus medica var. sarcodactylis, Dieffenbachia amoena cv. Tropic Snow; Spathiphyllum Supreme; Nephrolepis exaltata cv. Bostoniensis; Dracaena deremensis cv. Variegata emerged as the species with the greatest capacity to remove benzene from indoor air.

  14. Possible effect of biotechnology on plant gene pools in Turkey

    PubMed Central

    Demir, Aynur

    2015-01-01

    The recent rapid developments in biotechnology have made great contributions to the study of plant gene pools. The application of in vitro methods in freeze storage and DNA protection techniques in fast production studies has made major advances. From that aspect, biotechnology is an indispensable means for the protection of plant gene pools, which includes the insurance of sustainable agriculture and development of species. Besides all the positive developments, one of the primary risks posed by the uncontrolled spreading of genetically modified organisms is the possibility for other non-target organisms to be negatively affected. Genes of plant origin should be given priority in this type of studies by taking into consideration such negative effects that may result in disruption of ecological balance and damage to plant genetic pools. Turkey, due to its ecological conditions and history, has a very important position in terms of plant gene pools. This richness ought to be protected without corrupting its natural quality and natural evolution process in order to provide the sources of species that will be required for future sustainable agricultural applications. Thus, attention should be paid to the use of biotechnological methods, which play an important role especially in the protection and use of local and original plant gene pools. PMID:26019612

  15. Treatment of reactive azo dye from textile wastewater by burhead (Echinodorus cordifolius L.) in constructed wetland: Effect of molecular size.

    PubMed

    Noonpui, Sirikan; Thiravetyan, Paitip

    2011-01-01

    The potential of burhead (Echinodorus cordifolius L.) for the treatment of textile wastewater has been investigated. Reactive red 2; RR2 [MW=615], reactive red 120; RR120 [MW=1469] and reactive red 141; RR141 [MW=1775] were studied in order to determine the effect of molecular size on the efficiency of dye removal by plants in batch systems of constructed wetlands under soil and soil-free conditions. Dye concentrations, total dissolve solids (TDS), conductivity and pH in the effluents, and the relative growth rates (RGR) of plants were measured. The highest efficiency of dye removal during 7 days under soil-free conditions was RR2 (33.09 μmol(RR2)kg(-1)(FW)), followed by RR120 (13.35 μmol(RR120)kg(-1)(FW)) and RR141 (10.57 μmol(RR141)kg(-1)(FW)), respectively. This suggests that the structure and size of dye molecule strongly affects the efficiency of dye removal by plant. The results from a synthetic wetland experiment found that dye removal was 96 % at 4 days and 6 days under soil and soil-free conditions, respectively. Furthermore, plants were able to decrease TDS (42 %), conductivity (50 %) and pH (from 9.5 to 7.4) within 2 days in the synthetic reactive red(141) dye wastewater (SRRW141) under soil-free conditions, thus demonstrating the potential of burhead for textile wastewater treatment.

  16. Radioactive Air Emissions Notice of Construction (NOC) for the Solid Waste Treatment Facility (T Plant) Fuel Removal Project

    SciTech Connect

    JOHNSON, R.E.

    2000-11-16

    This NOC describes the activities to remove all spent nuclear fuel (SNF) assemblies from the spent fuel pool in the T Plant Complex 221-T canyon for interim storage in the Canister Storage Building (CSB). The unabated total effective dose equivalent (TEDE) estimated for the public hypothetical maximally exposed individual (MEI) is 5.7 E-6 millirem (mrem) per year for this fuel removal NOC. The abated TEDE conservatively is estimated to account for 2.9 E-9 mrem per year to the MEI.

  17. Contrasting effects of different mammalian herbivores on sagebrush plant communities.

    PubMed

    Veblen, Kari E; Nehring, Kyle C; McGlone, Christopher M; Ritchie, Mark E

    2015-01-01

    Herbivory by both grazing and browsing ungulates shapes the structure and functioning of terrestrial ecosystems worldwide, and both types of herbivory have been implicated in major ecosystem state changes. Despite the ecological consequences of differences in diets and feeding habits among herbivores, studies that experimentally distinguish effects of grazing from spatially co-occurring, but temporally segregated browsing are extremely rare. Here we use a set of long-term exclosures in northern Utah, USA, to determine how domestic grazers vs. wild ungulate herbivores (including browsers and mixed feeders) affect sagebrush-dominated plant communities that historically covered ~62 million ha in North America. We sampled plant community properties and found that after 22 years grazing and browsing elicited perceptible changes in overall plant community composition and distinct responses by individual plant species. In the woody layer of the plant community, release from winter and spring wild ungulate herbivory increased densities of larger Wyoming big sagebrush (Artemisia tridentata, ssp. wyomingensis) at the expense of small sagebrush, while disturbance associated with either cattle or wild ungulate activity alone was sufficient to increase bare ground and reduce cover of biological soil crusts. The perennial bunchgrass, bottlebrush squirretail (Elymus elymoides), responded positively to release from summer cattle grazing, and in turn appeared to competitively suppress another more grazing tolerant perennial grass, Sandberg's blue grass (Poa secunda). Grazing by domestic cattle also was associated with increased non-native species biomass. Together, these results illustrate that ungulate herbivory has not caused sagebrush plant communities to undergo dramatic state shifts; however clear, herbivore-driven shifts are evident. In a dry, perennial-dominated system where plant community changes can occur very slowly, our results provide insights into potential long

  18. Contrasting Effects of Different Mammalian Herbivores on Sagebrush Plant Communities

    PubMed Central

    Veblen, Kari E.; Nehring, Kyle C.; McGlone, Christopher M.; Ritchie, Mark E.

    2015-01-01

    Herbivory by both grazing and browsing ungulates shapes the structure and functioning of terrestrial ecosystems worldwide, and both types of herbivory have been implicated in major ecosystem state changes. Despite the ecological consequences of differences in diets and feeding habits among herbivores, studies that experimentally distinguish effects of grazing from spatially co-occurring, but temporally segregated browsing are extremely rare. Here we use a set of long-term exclosures in northern Utah, USA, to determine how domestic grazers vs. wild ungulate herbivores (including browsers and mixed feeders) affect sagebrush-dominated plant communities that historically covered ~62 million ha in North America. We sampled plant community properties and found that after 22 years grazing and browsing elicited perceptible changes in overall plant community composition and distinct responses by individual plant species. In the woody layer of the plant community, release from winter and spring wild ungulate herbivory increased densities of larger Wyoming big sagebrush (Artemisia tridentata, ssp. wyomingensis) at the expense of small sagebrush, while disturbance associated with either cattle or wild ungulate activity alone was sufficient to increase bare ground and reduce cover of biological soil crusts. The perennial bunchgrass, bottlebrush squirretail (Elymus elymoides), responded positively to release from summer cattle grazing, and in turn appeared to competitively suppress another more grazing tolerant perennial grass, Sandberg’s blue grass (Poa secunda). Grazing by domestic cattle also was associated with increased non-native species biomass. Together, these results illustrate that ungulate herbivory has not caused sagebrush plant communities to undergo dramatic state shifts; however clear, herbivore-driven shifts are evident. In a dry, perennial-dominated system where plant community changes can occur very slowly, our results provide insights into potential long

  19. Streamlined Construction of the Cyanobacterial CO2-Fixing Organelle via Protein Domain Fusions for Use in Plant Synthetic Biology.

    PubMed

    Gonzalez-Esquer, C Raul; Shubitowski, Tyler B; Kerfeld, Cheryl A

    2015-09-01

    Bacterial microcompartments (BMCs) are self-assembling organelles that sequester segments of biochemical pathways within a protein shell. Given their functional diversity, BMCs constitute a rich source of metabolic modules for applications in synthetic biology. The carboxysome, the cyanobacterial BMC for CO(2) fixation, has attracted significant attention as a target for installation into chloroplasts and serves as the foundation for introducing other types of BMCs into plants. Carboxysome assembly involves a series of protein-protein interactions among at least six gene products to form a metabolic core, around which the shell assembles. This complexity creates significant challenges for the transfer, regulation, and assembly of carboxysomes, or any of the myriad of functionally distinct BMCs, into heterologous systems. To overcome this bottleneck, we constructed a chimeric protein in the cyanobacterium Synechococcus elongatus that structurally and functionally replaces four gene products required for carboxysome formation. The protein was designed based on protein domain interactions in the carboxysome core. The resulting streamlined carboxysomes support photosynthesis. This strategy obviates the need to regulate multiple genes and decreases the genetic load required for carboxysome assembly in heterologous systems. More broadly, the reengineered carboxysomes represent a proof of concept for a domain fusion approach to building multifunctional enzymatic cores that should be generally applicable to the engineering of BMCs for new functions and cellular contexts.

  20. Effects of Livestock Grazing and Well Construction on Prairie Vegetation Structure Surrounding Shallow Natural Gas Wells

    NASA Astrophysics Data System (ADS)

    Koper, N.; Molloy, K.; Leston, L.; Yoo, J.

    2014-11-01

    Short and sparse vegetation near shallow gas wells has generally been attributed to residual effects from well construction, but other mechanisms might also explain these trends. We evaluated effects of distance to shallow gas wells on vegetation and bare ground in mixed-grass prairies in southern Alberta, Canada, from 2010 to 2011. We then tested three hypotheses to explain why we found shorter vegetation and more bare ground near wells, using cattle fecal pat transects from 2012, and our vegetation quadrats. We evaluated whether empirical evidence suggested that observed patterns were driven by (1) higher abundance of crested wheatgrass ( Agropyron cristatum) near wells, (2) residual effects of well construction, or (3) attraction of livestock to wells. Crested wheatgrass occurrence was higher near wells, but this did not explain effects of wells on vegetation structure. Correlations between distance to wells and litter depth were the highest near newer wells, providing support for the construction hypothesis. However, effects of distance to wells on other vegetation metrics did not decline as time since well construction increased, suggesting that other mechanisms explained observed edge effects. Cattle abundance was substantially higher near wells, and this effect corresponded with changes in habitat structure. Our results suggest that both residual effects of well construction and cattle behavior may explain effects of shallow gas wells on habitat structure in mixed-grass prairies, and thus, to be effective, mitigation strategies must address both mechanisms.

  1. Effects of livestock grazing and well construction on prairie vegetation structure surrounding shallow natural gas wells.

    PubMed

    Koper, N; Molloy, K; Leston, L; Yoo, J

    2014-11-01

    Short and sparse vegetation near shallow gas wells has generally been attributed to residual effects from well construction, but other mechanisms might also explain these trends. We evaluated effects of distance to shallow gas wells on vegetation and bare ground in mixed-grass prairies in southern Alberta, Canada, from 2010 to 2011. We then tested three hypotheses to explain why we found shorter vegetation and more bare ground near wells, using cattle fecal pat transects from 2012, and our vegetation quadrats. We evaluated whether empirical evidence suggested that observed patterns were driven by (1) higher abundance of crested wheatgrass (Agropyron cristatum) near wells, (2) residual effects of well construction, or (3) attraction of livestock to wells. Crested wheatgrass occurrence was higher near wells, but this did not explain effects of wells on vegetation structure. Correlations between distance to wells and litter depth were the highest near newer wells, providing support for the construction hypothesis. However, effects of distance to wells on other vegetation metrics did not decline as time since well construction increased, suggesting that other mechanisms explained observed edge effects. Cattle abundance was substantially higher near wells, and this effect corresponded with changes in habitat structure. Our results suggest that both residual effects of well construction and cattle behavior may explain effects of shallow gas wells on habitat structure in mixed-grass prairies, and thus, to be effective, mitigation strategies must address both mechanisms. PMID:25078539

  2. Selection for niche differentiation in plant communities increases biodiversity effects.

    PubMed

    Zuppinger-Dingley, Debra; Schmid, Bernhard; Petermann, Jana S; Yadav, Varuna; De Deyn, Gerlinde B; Flynn, Dan F B

    2014-11-01

    In experimental plant communities, relationships between biodiversity and ecosystem functioning have been found to strengthen over time, a fact often attributed to increased resource complementarity between species in mixtures and negative plant-soil feedbacks in monocultures. Here we show that selection for niche differentiation between species can drive this increasing biodiversity effect. Growing 12 grassland species in test monocultures and mixtures, we found character displacement between species and increased biodiversity effects when plants had been selected over 8 years in species mixtures rather than in monocultures. When grown in mixtures, relative differences in height and specific leaf area between plant species selected in mixtures (mixture types) were greater than between species selected in monocultures (monoculture types). Furthermore, net biodiversity and complementarity effects were greater in mixtures of mixture types than in mixtures of monoculture types. Our study demonstrates a novel mechanism for the increase in biodiversity effects: selection for increased niche differentiation through character displacement. Selection in diverse mixtures may therefore increase species coexistence and ecosystem functioning in natural communities and may also allow increased mixture yields in agriculture or forestry. However, loss of biodiversity and prolonged selection of crops in monoculture may compromise this potential for selection in the longer term.

  3. ELWIRA "Plants, wood, steel, concrete - a lifecycle as construction materials": University meets school - science meets high school education

    NASA Astrophysics Data System (ADS)

    Strauss-Sieberth, Alexandra; Strauss, Alfred; Kalny, Gerda; Rauch, Hans Peter; Loiskandl, Willibald

    2016-04-01

    The research project "Plants, wood, steel, concrete - a lifecycle as construction materials" (ELWIRA) is in the framework of the Sparkling Science programme performed by the University of Natural Resources and Life Sciences together with the Billroth Gymnasium in Vienna. The targets of a Sparkling Science project are twofold (a) research and scientific activities should already be transferred in the education methods of schools in order to fascinate high school students for scientific methods and to spark young people's interest in research, and (b) exciting research questions not solved and innovative findings should be addressed. The high school students work together with the scientists on their existing research questions improve the school's profile and the high school student knowledge in the investigated Sparkling Science topic and can lead to a more diverse viewing by the involvement of the high school students. In the project ELWIRA scientists collaborate with the school to quantify and evaluate the properties of classical building materials like concrete and natural materials like plants and woodlogs in terms of their life cycle through the use of different laboratory and field methods. The collaboration with the high school students is structured in workshops, laboratory work and fieldworks. For an efficient coordination/communication, learning and research progress new advanced electronic media like "Moodle classes/courses" have been used and utilized by the high school students with great interest. The Moodle classes are of high importance in the knowledge transfer in the dialogue with the high school students. The research project is structured into four main areas associated with the efficiencies of building materials: (a) the aesthetic feeling of people in terms of the appearance of materials and associated structures will be evaluated by means of jointly developed and collected questionnaires. The analysis, interpretation and evaluation are carried

  4. The Effect of Anchor Test Construction on Scale Drift

    ERIC Educational Resources Information Center

    Antal, Judit; Melican, Gerald; Proctor, Thomas; Wiley, Andrew

    2010-01-01

    Presented at the Annual Meeting of National Council on Measurement in Education (NCME) in 2010. The focus of the research is to investigate the effect of applying the Sinharay & Holland (2007) midi-test idea for building anchor tests to an on-going testing program with a series of versions of the test and comparing these results to the more…

  5. Biological effects due to weak magnetic fields on plants

    NASA Astrophysics Data System (ADS)

    Belyavskaya, N.

    In the evolution process, living organisms have experienced the action of the Earth's magnetic field (MF) that is a natural component of our environment. It is known that a galactic MF induction does not exceed 0.1 nT, since investigations of weak magnetic field (WMF) effects on biological systems have attracted attention of biologists due to planning long-term space flights to other planets where the magnetizing force is near 10-5 Oe. However, the role of WMF and its influence on organisms' functioning are still insufficiently investigated. A large number of experiments with seedlings of different plant species placed in WMF has found that the growth of their primary roots is inhibited during the early terms of germination in comparison with control. The proliferation activity and cell reproduction are reduced in meristem of plant roots under WMF application. The prolongation of total cell reproductive cycle is registered due to the expansion of G phase in1 different plant species as well as of G phase in flax and lentil roots along with2 relative stability of time parameters of other phases of cell cycle. In plant cells exposed to WMF, the decrease in functional activity of genome at early prereplicate period is shown. WMF causes the intensification in the processes of proteins' synthesis and break-up in plant roots. Qualitative and quantitative changes in protein spectrum in growing and differentiated cells of plant roots exposed to WMF are revealed. At ultrastructural level, there are observed such ultrastructural peculiarities as changes in distribution of condensed chromatin and nucleolus compactization in nuclei, noticeable accumulation of lipid bodies, development of a lytic compartment (vacuoles, cytosegresomes and paramural bodies), and reduction of phytoferritin in plastids in meristem cells of pea roots exposed to WMF. Mitochondria are the most sensitive organelle to WMF application: their size and relative volume in cells increase, matrix is electron

  6. Plant-Based and Plant-Rich Diet Patterns during Gestation: Beneficial Effects and Possible Shortcomings.

    PubMed

    Pistollato, Francesca; Sumalla Cano, Sandra; Elio, Iñaki; Masias Vergara, Manuel; Giampieri, Francesca; Battino, Maurizio

    2015-09-01

    Environmental and lifestyle factors are known to play an important role during gestation, determining newborns' health status and influencing their risk of being subject to certain noncommunicable diseases later in life. In particular, maternal nutritional patterns characterized by a low intake of plant-derived foods could increase the risk of gestation-related issues, such as preeclampsia and pregravid obesity, increase genotoxicant susceptibility, and contribute to the onset of pediatric diseases. In particular, the risk of pediatric wheeze, diabetes, neural tube defects, orofacial clefts, and some pediatric tumors seems to be reduced by maternal intake of adequate amounts of vegetables, fruits, and selected antioxidants. Nevertheless, plant-based diets, like any other diet, if improperly balanced, could be deficient in some specific nutrients that are particularly relevant during gestation, such as n-3 (ω-3) fatty acids, vitamin B-12, iron, zinc, and iodine, possibly affecting the offspring's health state. Here we review the scientific literature in this field, focusing specifically on observational studies in humans, and highlight protective effects elicited by maternal diets enriched in plant-derived foods and possible issues related to maternal plant-based diets. PMID:26374180

  7. Effect of lead and cadmium on aquatic plant Hydrilla verticillata.

    PubMed

    Singh, Alka; Kumar, Chandra Shekhar; Agarwal, Abha

    2013-11-01

    Absorption of different concentrations of Lead (Pb) and Cadmium (Cd) by aquatic plant Hydrilla vertcillato was measured during winter season for two different durations i.e. 3 days and 7 days. Effect of Pb and Cd was evaluated by analyzing various parameters such as biomass, total chlorophyll, carotenoid, protein, nitrate reductase activity, SOD (super oxide dismutase) and heavy metal uptake. Increase in biomass, total chlorophyll, protein and nitrate reductase activity was noticed at lower concentration of both metals whereas at higher metal concentrations of Pb and Cd, decrease in these parameters was observed i.e. it was concentration and duration dependent. Increase in carotenoid and SOD levels at high concentration of Pb and Cd indicated its ability of stress tolerance. Accumulation of Pb by test plant was found to be more than Cd at low concentration. Higher concentration of Cd and Pb caused toxicity which resulted in reduced plant growth and physiological activities. PMID:24555332

  8. Effect of treatment in a constructed wetland on toxicity of textile wastewater

    USGS Publications Warehouse

    Baughman, G.L.; Perkins, W.S.; Lasier, P.J.; Winger, P.V.

    2003-01-01

    Constructed wetlands for treating wastewater have proliferated in recent years and their characteristics have been studied extensively. In most cases, constructed wetlands have been used primarily for removal of nutrients and heavy metals. Extensive literature is available concerning construction and use of wetlands for treatment of wastewater. Even so, quantitative descriptions of wetland function and processes are highly empirical and difficult to extrapolate. The processes involved in removal of pollutants by wetlands are poorly understood, especially for waste streams as complex as textile effluents. The few studies conducted on treatment of textile wastewater in constructed wetlands were cited in earlier publications. Results of a two-year study of a full-scale wetland treating textile effluent are presented here. The paper describes the effects of the wetland on aquatic toxicity of the wastewater and draws conclusions about the utility and limitations of constructed wetlands for treatment of textile effluents.

  9. Differential Effect of Plant Lipids on Membrane Organization

    PubMed Central

    Grosjean, Kevin; Mongrand, Sébastien; Beney, Laurent; Simon-Plas, Françoise; Gerbeau-Pissot, Patricia

    2015-01-01

    The high diversity of the plant lipid mixture raises the question of their respective involvement in the definition of membrane organization. This is particularly the case for plant plasma membrane, which is enriched in specific lipids, such as free and conjugated forms of phytosterols and typical phytosphingolipids, such as glycosylinositolphosphoceramides. This question was here addressed extensively by characterizing the order level of membrane from vesicles prepared using various plant lipid mixtures and labeled with an environment-sensitive probe. Fluorescence spectroscopy experiments showed that among major phytosterols, campesterol exhibits a stronger ability than β-sitosterol and stigmasterol to order model membranes. Multispectral confocal microscopy, allowing spatial analysis of membrane organization, demonstrated accordingly the strong ability of campesterol to promote ordered domain formation and to organize their spatial distribution at the membrane surface. Conjugated sterol forms, alone and in synergy with free sterols, exhibit a striking ability to order membrane. Plant sphingolipids, particularly glycosylinositolphosphoceramides, enhanced the sterol-induced ordering effect, emphasizing the formation and increasing the size of sterol-dependent ordered domains. Altogether, our results support a differential involvement of free and conjugated phytosterols in the formation of ordered domains and suggest that the diversity of plant lipids, allowing various local combinations of lipid species, could be a major contributor to membrane organization in particular through the formation of sphingolipid-sterol interacting domains. PMID:25575593

  10. The Effects of Cold Stress on Photosynthesis in Hibiscus Plants.

    PubMed

    Paredes, Miriam; Quiles, María José

    2015-01-01

    The present work studies the effects of cold on photosynthesis, as well as the involvement in the chilling stress of chlororespiratory enzymes and ferredoxin-mediated cyclic electron flow, in illuminated plants of Hibiscus rosa-sinensis. Plants were sensitive to cold stress, as indicated by a reduction in the photochemistry efficiency of PSII and in the capacity for electron transport. However, the susceptibility of leaves to cold may be modified by root temperature. When the stem, but not roots, was chilled, the quantum yield of PSII and the relative electron transport rates were much lower than when the whole plant, root and stem, was chilled at 10°C. Additionally, when the whole plant was cooled, both the activity of electron donation by NADPH and ferredoxin to plastoquinone and the amount of PGR5 polypeptide, an essential component of the cyclic electron flow around PSI, increased, suggesting that in these conditions cyclic electron flow helps protect photosystems. However, when the stem, but not the root, was cooled cyclic electron flow did not increase and PSII was damaged as a result of insufficient dissipation of the excess light energy. In contrast, the chlororespiratory enzymes (NDH complex and PTOX) remained similar to control when the whole plant was cooled, but increased when only the stem was cooled, suggesting the involvement of chlororespiration in the response to chilling stress when other pathways, such as cyclic electron flow around PSI, are insufficient to protect PSII. PMID:26360248

  11. Effects of biogas digestate on soil properties and plant growth

    NASA Astrophysics Data System (ADS)

    Gulyás, Miklós; Füleky, György

    2013-04-01

    Farming methods and food industries generate large amounts manure and other useful raw materials that need safe disposal. Following the international trends great numbers of biogas plants were opened during the last few years in Hungary. However this issue presents a number of new questions, including the subsequent use of anaerobic fermentation residues. So far we have only limited information about it's agricultural applications. Farmers and authorities are very skeptic because feedstocks are very different so the endproduct will be different, too. However, this endproduct can be applied as fertilizer. The aim of our work is to determine the effects of this product in plant-soil system. Digestate contains high amount of nitrogen which is present mainly ammonium form and this form can cause root depression and lower germination rates. Pot experiments were established with different rates of nitrogen content (80 kg ha-1N, 120 kg ha-1N, 170 kg ha-1N, and control). Maximum rates were determine by the Nitrate Directive. Soil moisture was 60% of maximum of water capacity. Digestate and distilled water were homogenized and added to 200g loamy soil. Rye-grass (Lolium perenne) was applied as a test plant. Treatments were randomized design and 10 replications. Three pot from each treatment were used to observe the germination and progress of plants. We investigated the effect of the digestate on nitrate- and ammonium-ion content of soil. The amount of nitrate- and ammonium-N of soil was determine with distillation. The ammonium-N levels increased with the doses on the first day but on the sixth-seventh day this amount totally falled down, because NH4-N transformed to NO3-N. Nitrate level increased continuously untill the tenth day, later decreased as the result of the plant and microbes consumption. The increasing doses inhibited the germination and root development of the plants. We experienced fewer roots, which were different form control.

  12. Management and integration of engineering and construction activities: Lessons learned from the AP1000{sup R} nuclear power plant China project

    SciTech Connect

    McCullough, M. C.; Ebeling-Koning, D.; Evans, M. C.

    2012-07-01

    The lessons learned during the early phase of design engineering and construction activities for the AP1000 China Project can be applied to any project involving multiple disciplines and multiple organizations. Implementation of a first-of-a-kind design to directly support construction activities utilizing resources assigned to design development and design delivery creates challenges with prioritization of activities, successful closure of issues, and communication between site organizations and the home office. To ensure successful implementation, teams were assigned and developed to directly support construction activities including prioritization of activities, site communication and ensuring closure of site emergent issues. By developing these teams, the organization is better suited to meet the demands of the construction schedule while continuing with design evolution of a standard plant and engineering delivery for multiple projects. For a successful project, proper resource utilization and prioritization are key for overcoming obstacles and ensuring success of the engineering organization. (authors)

  13. Hydrogeochemical and isotopic studies of tunnel seepage water in the YangYang power plant construction site, Korea

    NASA Astrophysics Data System (ADS)

    Yoo, I.; Yun, S.

    2001-12-01

    Underground tunnel is now constructing at the YangYang power plant construction site after 1996 for an electric power supply. Geologic structures in the area are dominanted by fault fracture zones with altitudes of N5E80SE-90 and N75E40-70SE, which act as major conduits of groundwater flow. Tunnel seepage waters (TSW; N = 21) and surface waters (N = 3) were collected from the area of Precambrian metamorphic rocks and were examined for hydrogeochemical and isotopic characteristics. TSW has the wide ranges of pH (8.0-9.7) and TDS content (70.3-870.9 mgl). The TDS values reflect varying degrees of waterrock interaction. TSW can be classified into two hydrochemical groups, based on the plots on a Piper¡_s diagram as well as ANOVA test of hydrochemical data. These are (the data in parenthesis indicate mean concentrations): Na-HCO3 type (Na = 188.5 mgl, K = 2.0 mgl, Cl = 15.6 mgl, F = 16.3 mgl; N = 3), Ca(¡_Na)-HCO3 type (Na = 16.1 mgl, K = 0.4 mgl, Cl = 3.5 mg/l, F = 3.8 mgl; N = 18). The Na-HCO3 type waters record mainly the albite dissolution and occurs restrictedly in deep tunnel sites (EL= >640 m a.s.l), whereas the Ca(¡_Na)-HCO3 type waters occurs in shallower tunnel sites (EL= <600 m a.s.l) and was formed through dissolution of mainly calcite and soluble silicates as well as cation exchange. The former type waters also have lower oxygen and hydrogen isotope values and higher tritium contents. With an increasing depth to the sampling site, the oxygen isotopic values of TSW progressively decrease with an isotopic gradient of -0.3 permill per 100 m (standard deviation = 0.001). By combining with available informations such as structural geology and tunnel design, we propose a hydrogeochemical evolution model for the observed bimodal patterns of hydrogeochemical and isotopic data.

  14. Effect of medicinal plants on the crystallization of cholesterol

    NASA Astrophysics Data System (ADS)

    Saraswathi, N. T.; Gnanam, F. D.

    1997-08-01

    One of the least desirable calcifications in the human body is the mineral deposition in atherosclerosis plaques. These plaques principally consist of lipids such as cholesterol, cholesteryl esters, phospholipids and triglycerides. Chemical analysis of advanced plaques have shown the presence of considerable amounts of free cholesterol identified as cholesterol monohydrate crystals. Cholesterol has been crystallized in vitro. The extracts of some of the Indian medicinal plants detailed below were used as additives to study their effect on the crystallization behaviour of cholesterol. It has been found that many of the herbs have inhibitory effect on the crystallization such as nucleation, crystal size and habit modification. The inhibitory effect of the plants are graded as Commiphora mughul > Aegle marmeleos > Cynoden dactylon > Musa paradisiaca > Polygala javana > Alphinia officinarum > Solanum trilobatum > Enicostemma lyssopifolium.

  15. Ecotoxicological effects of carbon nanomaterials on algae, fungi and plants.

    PubMed

    Basiuk, Elena V; Ochoa-Olmos, Omar E; De la Mora-Estrada, León F

    2011-04-01

    The ecotoxicological effects of carbon nanomateriales (CNMs), namely fullerenes and carbon nanotubes, on algae, fungi and plants are analyzed. In different toxicity tests, both direct and indirect effects were found. The direct effects are determined by nanomaterial chemical composition and surface reactivity, which might catalyze redox reactions in contact with organic molecules and affect respiratory processes. Some indirect effects of carbon nanoparticles (CNPs) are physical restraints or release of toxic ions. Accumulation of CNPs in photosynthetic organs provokes obstruction in stomata, foliar heating and alteration in physiological processes. The phytotoxicity studies of CNMs should be focused on determining phytotoxicity mechanisms, size distribution of CNPs in solution, uptake and translocation of nanoparticles by plants, on characterization of their physical and chemical properties in rhizosphere and on root surfaces. More studies on plants and algae, as a part of food chain, are needed to understand profoundly the toxicity and health risks of CNMs as ecotoxicological stressors. Correct and detailed physical and chemical characterization of CNMs is very important to establish the exposure conditions matching the realistic ones. Ecotoxicity experiments should include examinations of both short and long-term effects. One must take into account that real carbon nanomaterials are complex mixtures of carbon forms and metal residues of variable chemistry and particle size, and the toxicity reported may reflect these byproducts/residues/impurities rather than the primary material structure. One more recommendation is not only to focus on the inherent toxicity of nanoparticles, but also consider their possible interactions with existing environmental contaminants.

  16. Antimicrobial and cytotoxic effects of Mexican medicinal plants.

    PubMed

    Jacobo-Salcedo, Maria del Rosario; Alonso-Castro, Angel Josabad; Salazar-Olivo, Luis A; Carranza-Alvarez, Candy; González-Espíndola, Luis Angel; Domínguez, Fabiola; Maciel-Torres, Sandra Patricia; García-Lujan, Concepción; González-Martínez, Marisela del Rocio; Gómez-Sánchez, Maricela; Estrada-Castillón, Eduardo; Zapata-Bustos, Rocio; Medellin-Milán, Pedro; García-Carrancá, Alejandro

    2011-12-01

    The antimicrobial effects of the Mexican medicinal plants Guazuma ulmifolia, Justicia spicigera, Opuntia joconostle, O. leucotricha, Parkinsonia aculeata, Phoradendron longifolium, P. serotinum, Psittacanthus calyculatus, Tecoma stans and Teucrium cubense were tested against several human multi-drug resistant pathogens, including three Gram (+) and five Gram (-) bacterial species and three fungal species using the disk-diffusion assay. The cytotoxicity of plant extracts on human cancer cell lines and human normal non-cancerous cells was also evaluated using the MTT assay. Phoradendron longifolium, Teucrium cubense, Opuntia joconostle, Tecoma stans and Guazuma ulmifolia showed potent antimicrobial effects against at least one multidrug-resistant microorganism (inhibition zone > 15 mm). Only Justicia spicigera and Phoradendron serotinum extracts exerted active cytotoxic effects on human breast cancer cells (IC50 < or = 30 microg/mL). The results showed that Guazuma ulmifolia produced potent antimicrobial effects against Candida albicans and Acinetobacter lwoffii, whereas Justicia spicigera and Phoradendron serotinum exerted the highest toxic effects on MCF-7 and HeLa, respectively, which are human cancer cell lines. These three plant species may be important sources of antimicrobial and cytotoxic agents.

  17. Antimony contamination and its effect on Trifolium plants

    NASA Astrophysics Data System (ADS)

    Corrales, Isabel; Barceló, Juan; Bech, Jaume; Poschenrieder, Charlotte

    2014-05-01

    Antimony is not an essential element and soil Sb contents usually are low.However, soil contamination by Sb has increased in the last years due to the human activities (combustion of fossil fuels, mining, waste incineration, smelting, shooting and road traffic). The main objective of this work was to study the effect of different concentrations of antimony (KSb(OH)6) in order to evaluate the effect on growth and Sb uptake on Trifolium pratense cv. Milvus and Trifolium repens. Our results show that Sb accumulated both in roots and shoots of clover without any negative effect on root growth, cellular viability and lipid peroxidation. This absence of toxicity sympthoms in clover plants could be very dangerous because Sb can be inadvertedly incorporated into the trophic chain causing toxic effects both in animals and humans. The absence of toxic effects on plants does not seem to be due to detoxification by phytochelatins because the use of the gamma-glutamylcysteine synthetase inhibitor, L-buthionine-[S,R]-sulphoximine (BSO) did not enhance Sb toxicity to plants. (Supported by the Spanish MICINN project BFU2010-14873)

  18. Effects of Road De-icing Salts in Constructed Wetlands

    NASA Astrophysics Data System (ADS)

    Silver, P.

    2005-05-01

    In November 2003, a 4-lane highway and 6 mitigation wetlands were opened across the Penn State campus, Erie, Pennsylvania. Road runoff overflows into 1 wetland (T3), and another (R3) receives salt spray and plowed snow. I have logged conductivity and temperature hourly at the sediment-water interface in R3 and T3 since January 2004, and I measure conductivity, temperature, and chironomid density biweekly in all 6 wetlands. Salinity in the wetlands that receive no salt is 0 psu. Biweekly checks of conductivity grossly underestimated winter salinities in T3 and R3. Between January and March 2004, salinity was >5 psu 5 times in R3, and >10 psu 6 times and >30 psu twice in T3. Flushing rates were similar in both wetlands, but time constants were significantly greater in T3 than R3. Salinities returned to 0 psu in both wetlands in May. Chironomid density was significantly lower in T3 than in all other wetlands in summer and autumn, long after salinities at the sediment-water interface returned to 0. Thus, chironomid densities indicated persistent biological effects of de-icers even when measurable salinities were 0 psu. Winter 2005 data show decreasing chironomid density in T3, whereas densities are increasing in the other wetlands.

  19. Effects of host-plant population size and plant sex on a specialist leaf-miner

    NASA Astrophysics Data System (ADS)

    Bañuelos, María-José; Kollmann, Johannes

    2011-03-01

    Animal population density has been related to resource patch size through various hypotheses such as those derived from island biogeography and resource concentration theory. This theoretical framework can be also applied to plant-herbivore interactions, and it can be modified by the sex of the host-plant, and density-dependent relationships. Leaf-miners are specialised herbivores that leave distinct traces on infested leaves in the form of egg scars, mines, signs of predation and emergence holes. This allows the life cycle of the insect to be reconstructed and the success at the different stages to be estimated. The main stages of the leaf-miner Phytomyza ilicis were recorded in eleven populations of the evergreen host Ilex aquifolium in Denmark. Survival rates were calculated and related to population size, sex of the host plant, and egg and mine densities. Host population size was negatively related to leaf-miner prevalence, with larger egg and mine densities in small populations. Percentage of eggs hatching and developing into mines, and percentage of adult flies emerging from mines also differed among host populations, but were not related to population size or host cover. Feeding punctures left by adults were marginally more frequent on male plants, whereas egg scars and mines were more common on females. Overall survival rate from egg stage to adult emergence was higher on female plants. Egg density was negatively correlated with hatching, while mine density was positively correlated with emergence of the larvae. The inverse effects of host population size were not in line with predictions based on island biogeography and resource concentration theory. We discuss how a thorough knowledge of the immigration behaviour of this fly might help to understand the patterns found.

  20. 10 CFR Appendix N to Part 52 - Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple... construct and operate nuclear power reactors of identical design (“common design”) to be located at...

  1. 10 CFR Appendix N to Part 52 - Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple... construct and operate nuclear power reactors of identical design (“common design”) to be located at...

  2. 10 CFR Appendix N to Part 52 - Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple... construct and operate nuclear power reactors of identical design (“common design”) to be located at...

  3. 10 CFR Appendix N to Part 52 - Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple... construct and operate nuclear power reactors of identical design (“common design”) to be located at...

  4. 10 CFR Appendix N to Part 52 - Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple... construct and operate nuclear power reactors of identical design (“common design”) to be located at...

  5. Familiarity effects in the construction of facial-composite images using modern software systems.

    PubMed

    Frowd, Charlie D; Skelton, Faye C; Butt, Neelam; Hassan, Amal; Fields, Stephen; Hancock, Peter J B

    2011-12-01

    We investigate the effect of target familiarity on the construction of facial composites, as used by law enforcement to locate criminal suspects. Two popular software construction methods were investigated. Participants were shown a target face that was either familiar or unfamiliar to them and constructed a composite of it from memory using a typical 'feature' system, involving selection of individual facial features, or one of the newer 'holistic' types, involving repeated selection and breeding from arrays of whole faces. This study found that composites constructed of a familiar face were named more successfully than composites of an unfamiliar face; also, naming of composites of internal and external features was equivalent for construction of unfamiliar targets, but internal features were better named than the external features for familiar targets. These findings applied to both systems, although benefit emerged for the holistic type due to more accurate construction of internal features and evidence for a whole-face advantage. STATEMENT OF RELEVANCE: This work is of relevance to practitioners who construct facial composites with witnesses to and victims of crime, as well as for software designers to help them improve the effectiveness of their composite systems.

  6. Evaluation of PPCPs removal in a combined anaerobic digester-constructed wetland pilot plant treating urban wastewater.

    PubMed

    Reyes-Contreras, C; Matamoros, V; Ruiz, I; Soto, M; Bayona, J M

    2011-08-01

    The removal efficiency of 16 pharmaceuticals and personal care products (PPCPs) from urban wastewater (dissolved and particulate phases) was evaluated for the first time in a hybrid pilot plant consisting of an upflow anaerobic sludge blanket reactor followed by two sequentially connected horizontal flow constructed wetlands: a surface flow wetland (SF CW) and a subsurface flow wetland (SSF CW). Whereas the PPCP removal associated with the dissolved phase exhibited a seasonal pattern, the fraction associated with the suspended solids showed less seasonality. In the dissolved phase, the overall removal efficiency in summer ranged from 70% to 85% for salicylic acid (SAL), methyl dihydrojasmonate, caffeine (CAF), ketoprofen and triclosan, whereas in winter it declined for most of the PPCPs to between 30% and 50%, except for CAF and SAL (>80%) and carbamazepine and butylated hydroxyl toluene (11-18%). In the suspended solids, the removal exceeded 80% for most of the target PPCPs. The efficiency of the different treatment steps was also compound-dependent, but the SF CW generally exhibited the highest removal efficiency for most of the contaminants analyzed. The characterization of the organic matter retained in the wetland gravel beds revealed the occurrence of hydrophobic contaminants such as phthalate esters and fragrances at moderate concentrations (i.e., up to 3.5 μg kg(-1)), which declined strongly over the course of the different treatment steps. In the SF CW, the net mass accumulation rates of tonalide and galaxolide were 4 and 23 gy(-1) respectively, whereas in the SSF CW they were 0.3 and 1.8 gy(-1) respectively.

  7. Water quality in a surface-flow constructed treatment wetland polishing tertiary effluent from a municipal wastewater treatment plant.

    PubMed

    Beutel, Marc W

    2012-01-01

    Constructed treatment wetlands (CTWs) are unique ecotechnologies that can sustainably treat a range of wastewaters. This study focused on a 0.23 ha vegetated surface-flow CTW polishing nitrate-rich (3-6 mg-N/L) tertiary effluent from a municipal wastewater treatment plant. Water quality was monitored longitudinally in the fall of 2009 and 2010. The CTW cooled water by from around 20 °C to <15 °C in both years. Longitudinal temperature profiles were successfully modeled using an energy balance approach (2009 R(2) = 0.69; 2010 R(2) = 0.92). The magnitude of key model fitting parameters, including albedo (0.1-0.2) and convective transfer coefficient (0.1-0.9 MJ/m(2) d °C), were within ranges reported in the literature. In both years, dissolved oxygen decreased through the wetland from 6-7 mg/L to 3-4 mg/L, yielding an oxygen mass consumption rate of 0.08-0.09 g/m(2) d. Longitudinal nitrate profiles were well represented by the P-k-C* model (2009 R(2) = 0.88; 2010 R(2) = 0.92). First order removal rates were 20.2 m/yr in 2009 and 29.0 m/yr in 2010 at a P value of 6.0. Levels of ammonia and total phosphorus increased negligibly through the wetland, remaining below 0.25 mg/L. This study shows that vegetated surface-flow CTWs are well suited to cool and polish low-BOD nitrate-dominated tertiary effluents with little degradation of other water quality parameters of concern, including phosphorus and ammonia. PMID:22925872

  8. Effectiveness of protected areas in maintaining plant production.

    PubMed

    Tang, Zhiyao; Fang, Jingyun; Sun, Jinyu; Gaston, Kevin J

    2011-01-01

    Given the central importance of protected area systems in local, regional and global conservation strategies, it is vital that there is a good understanding of their effectiveness in maintaining ecological functioning. Here, we provide, to our knowledge, the first such global analysis, focusing on plant production, a "supporting" ecosystem function necessary for multiple other ecosystem services. We use data on the normalized difference vegetation index (NDVI) as a measure of variation in plant production in the core, boundary and surroundings of more than 1000 large protected areas over a 25 year period. Forested protected areas were higher (or similar), and those non-forested were lower (or similar), in NDVI than their surrounding areas, and these differences have been sustained. The differences from surrounding areas have increased for evergreen broadleaf forests and barren grounds, decreased for grasslands, and remained similar for deciduous forests, woodlands, and shrublands, reflecting different pressures on those surroundings. These results are consistent with protected areas being effective both in the representation and maintenance of plant production. However, widespread overall increases in NDVI during the study period suggest that plant production within the core of non-forested protected areas has become higher than it was in the surroundings of those areas in 1982, highlighting that whilst the distinctiveness of protected areas from their surroundings has persisted the nature of that difference has changed.

  9. [Effect of transgenic plants on biodiversity of agroecosystem].

    PubMed

    Nie, Chengrong; Wang, Jianwu; Luo, Shiming

    2003-08-01

    The effect of transgenic plants on the biodiversity of agroecosystem is an important environmental issue. There are many researches in this field at home and abroad recently. This paper reviewed the advances of the researches based on three levels of biodiversity as genetic diversity, species diversity and ecosystem diversity. They included following aspects: the effect of insect-resistant transgenic crops on target pest; the effect of herbicide-resistant transgenic crops on crops and wild weedy relatives; the effect of virus-resistant transgenic crops on virus; and the effect of transgenic crops on non-target organisms. This paper also discussed the effect of transgenic crops on soil ecosystem and crop genetic diversity. Their potential risks included uncontrolled flows of genes to wild relatives; development of herbicide, insect, and virus resistance in wild relatives; reduced crop genetic diversity; and adverse effects on organisms that were not pests, such as beneficial insects.

  10. Mutagenic effects of heavy ion radiation in plants

    NASA Technical Reports Server (NTRS)

    Mei, M.; Deng, H.; Lu, Y.; Zhuang, C.; Liu, Z.; Qiu, Q.; Qiu, Y.; Yang, T. C.

    1994-01-01

    Genetic and developmental effects of heavy ions in maize and rice were investigated. Heavy particles with various charges and energies were accelerated at the BEVALAC. The frequency of occurrence of white-yellow stripes on leaves of plants developed from irradiated maize seeds increased linearly with dose, and high Linear Energy Transfer (LET) heavy charged particles, e.g., neon, argon, and iron, were 2-12 times as effective as gamma rays in inducing this type of mutation. The effectiveness of high-LET heavy ion in (1) inhibiting rice seedling growth, (2) reducing plant fertility, (3) inducing chromosome aberration and micronuclei in root tip cells and pollen mother cells of the first generation plants developed from exposed seeds, and (4) inducing mutation in the second generation, were greater than that of low-LET gamma rays. All effects observed were dose-dependent; however, there appeared to be an optimal range of doses for inducing certain types of mutation, for example, for argon ions (400 MeV/u) at 90-100 Gy, several valuable mutant lines with favorable characters, such as semidwarf, early maturity and high yield ability, were obtained. Experimental results suggest that the potential application of heavy ions in crop improvement is promising. Restriction-fragment-length-polymorphism (RFLP) analysis of two semidwarf mutants induced by argon particles revealed that large DNA alterations might be involved in these mutants.

  11. Effects of nuclear power plants on residential property values

    SciTech Connect

    Gamble, H.B.; Downing, R.H.

    1982-11-01

    The results are presented of two studies done on the effects of nuclear power plants on residential property values. One study, which examined property values in the vicinity of four Northeastern power plants prior to the March, 1979 TMI accident, found no significant evidence positively or negatively. Using the same analytic approach, residences in the TMI area were surveyed after the accident and again no determining evidence was found upon consideration of all of 1979. The methodology of both studies is examined along with a discussion of the hedonic price model on which they were based. It is speculated, however, that the difficulties involved in the clean up and the resultant rise in utility prices may inadvertently create long-term capitalization effects. 18 references.

  12. Effects of alkyl parabens on plant pathogenic fungi.

    PubMed

    Ito, Shinsaku; Yazawa, Satoru; Nakagawa, Yasutaka; Sasaki, Yasuyuki; Yajima, Shunsuke

    2015-04-15

    Alkyl parabens are used as antimicrobial preservatives in cosmetics, food, and pharmaceutical products. However, the mode of action of these chemicals has not been assessed thoroughly. In this study, we determined the effects of alkyl parabens on plant pathogenic fungi. All the fungi tested, were susceptible to parabens. The effect of linear alkyl parabens on plant pathogenic fungi was related to the length of the alkyl chain. In addition, the antifungal activity was correlated with the paraben-induced inhibition of oxygen consumption. The antifungal activity of linear alkyl parabens likely originates, at least in part, from their ability to inhibit the membrane respiratory chain, especially mitochondrial complex II. Additionally, we determined that some alkyl parabens inhibit Alternaria brassicicola infection of cabbage.

  13. Climate change effects on plant biomass alter dominance patterns and community evenness in an experimental old-field ecosystem

    SciTech Connect

    Kardol, Paul; Campany, Courtney E; Souza, Lara; Norby, Richard J; Weltzin, Jake; Classen, Aimee T

    2010-01-01

    Atmospheric and climatic change can alter plant biomass production and plant community composition. However, we know little about how climate change-induced alterations in biomass production affect plant community composition. To better understand how climate change will alter both individual plant species and community biomass we manipulated atmospheric [CO2], air temperature and precipitation in a constructed old-field ecosystem. Specifically, we compared the responses of dominant and subdominant species to our treatments, and explored how changes in plant dominance patterns alter community evenness over two years. Our study resulted in four major findings: 1) All treatments, elevated [CO2], warming and increased precipitation, increased plant biomass and the effects were additive rather than interactive, 2) Plant species differed in their response to the treatments, resulting in shifts in the proportional biomass of individual species, which altered the plant community composition; however, the plant community response was largely driven by the responses of the dominant species, 3) Precipitation explained most of the variation in plant community composition among treatments, and 4) Changes in precipitation caused a shift in the dominant species proportional biomass that resulted in higher community evenness in the dry relative to wet treatments. Interestingly, compositional and evenness responses of the subdominant community to the treatments did not always follow the responses of the whole plant community. Our data suggest that changes in plant dominance patterns and community evenness are an important part of community responses to climate change, and generally, that compositional shifts can have important consequences for the functioning of terrestrial ecosystems.

  14. Political Skill and Work Attitudes: A Comparison of Multiple Social Effectiveness Constructs.

    PubMed

    Banister, Christina M; Meriac, John P

    2015-01-01

    In the realm of social effectiveness constructs, political skill has seen increased attention as a predictor of work performance and attitudes. However, the extent that political skill is distinct from related variables in this area remains an important question. The current study examined the proportion of variance explained by political skill in job satisfaction and turnover intentions above and beyond other social effectiveness variables (i.e., social intelligence, emotional intelligence, agreeableness, and conscientiousness). Results indicated that political skill was the strongest predictor of these outcomes, and explained a significant proportion of variance in them, beyond the other four social effectiveness constructs. PMID:25425484

  15. [Effects of different years of planting Pennisetum sp. on the plant- and insect diversity in Pennisetum sp. communities].

    PubMed

    Lin, Xing-Sheng; Lin, Zhan-Xi; Lin, Dong-Mei; Lin, Hui; Luo, Hai-Ling; Hu, Ying-Ping; Lin, Chun-Mei; Zhu, Chao-Zhi

    2012-10-01

    This paper studied the effects of 1-, 2- and 3 years of planting Pennisetum sp. on the plant- and insect diversity in the Pennisetum sp. communities, taking the barren mountain land without planting Pennisetum sp. as the control (CK). Compared with CK, the plant species richness in Pennisetum sp. communities with different years of planting was lower, but the coverage was higher. The coverage in the Pennisetum sp. community having been planted for 3 years was the highest, up to 91.6%, and 75.8% higher than the CK. The insect species richness in the Pennisetum sp. communities having been planted for 1, 2 and 3 years was 3.6, 5.3 and 5.6 times of the CK, respectively. The plant- and insect diversity indices, including Simpson index, Shannon index, evenness, Brillouin index, and McIntosh index for the Pennisetum sp. communities with different years of planting were significantly higher than the CK, which indicated that the growth of Pennisetum sp. could affect the plant- and insect diversity. With the increasing year of planting, the plant- and insect diversity in Pennisetum sp. communities tended to be stable.

  16. Magnetic fluids effect upon growth processes in plants

    NASA Astrophysics Data System (ADS)

    Sala, F.

    1999-07-01

    The metabolic processes of plants growth and development take place according to some organic rules which are specific to their genetic potential. These processes may exhibit modifications of intensity, rhythm, sense, under the influence of the environmental conditions of agricultural systems, through certain factors and bioregulators artificially introduced by man. The results of some investigations regarding effects of biocompatible magnetic fluids (LMW 100 G) on the vegetal organism's (growth, development, fructifying, the level and quality of the yield precocity) are presented.

  17. Effect of Ultrasound on Sludge from Water Treatment Plant

    NASA Astrophysics Data System (ADS)

    Kim, Young U.; Ha, Junsoo; Yoon, Ki Yong; Lee, Seung-Hyun

    2004-10-01

    In this study, we investigated the effect of ultrasound on the reduction in the amount of heavy metals and the dewaterability of sludge from a water treatment plant. The investigation involved laboratory experiments, which were conducted under different conditions, including the energy levels of ultrasonic waves and treatment time. Results of the study show that ultrasound reduces the amount of heavy metals and enhances the dewaterability of sludge significantly. The degree of enhancement varies with ultrasonic energy and treatment time.

  18. Biological effects due to weak magnetic field on plants

    NASA Astrophysics Data System (ADS)

    Belyavskaya, N. A.

    2004-01-01

    magnetic field may cause different biological effects at the cellular, tissue and organ levels. They may be functionally related to systems that regulate plant metabolism including the intracellular Ca 2+ homeostasis. However, our understanding of very complex fundamental mechanisms and sites of interactions between weak magnetic fields and biological systems is still incomplete and still deserve strong research efforts.

  19. Learning from instructional explanations: effects of prompts based on the active-constructive-interactive framework.

    PubMed

    Roelle, Julian; Müller, Claudia; Roelle, Detlev; Berthold, Kirsten

    2015-01-01

    Although instructional explanations are commonly provided when learners are introduced to new content, they often fail because they are not integrated into effective learning activities. The recently introduced active-constructive-interactive framework posits an effectiveness hierarchy in which interactive learning activities are at the top; these are then followed by constructive and active learning activities, respectively. Against this background, we combined instructional explanations with different types of prompts that were designed to elicit these learning activities and tested the central predictions of the active-constructive-interactive framework. In Experiment 1, N = 83 students were randomly assigned to one of four combinations of instructional explanations and prompts. To test the active < constructive learning hypothesis, the learners received either (1) complete explanations and engaging prompts designed to elicit active activities or (2) explanations that were reduced by inferences and inference prompts designed to engage learners in constructing the withheld information. Furthermore, in order to explore how interactive learning activities can be elicited, we gave the learners who had difficulties in constructing the prompted inferences adapted remedial explanations with either (3) unspecific engaging prompts or (4) revision prompts. In support of the active < constructive learning hypothesis, we found that the learners who received reduced explanations and inference prompts outperformed the learners who received complete explanations and engaging prompts. Moreover, revision prompts were more effective in eliciting interactive learning activities than engaging prompts. In Experiment 2, N = 40 students were randomly assigned to either (1) a reduced explanations and inference prompts or (2) a reduced explanations and inference prompts plus adapted remedial explanations and revision prompts condition. In support of the constructive < interactive

  20. Learning from Instructional Explanations: Effects of Prompts Based on the Active-Constructive-Interactive Framework

    PubMed Central

    Roelle, Julian; Müller, Claudia; Roelle, Detlev; Berthold, Kirsten

    2015-01-01

    Although instructional explanations are commonly provided when learners are introduced to new content, they often fail because they are not integrated into effective learning activities. The recently introduced active-constructive-interactive framework posits an effectiveness hierarchy in which interactive learning activities are at the top; these are then followed by constructive and active learning activities, respectively. Against this background, we combined instructional explanations with different types of prompts that were designed to elicit these learning activities and tested the central predictions of the active-constructive-interactive framework. In Experiment 1, N = 83 students were randomly assigned to one of four combinations of instructional explanations and prompts. To test the active < constructive learning hypothesis, the learners received either (1) complete explanations and engaging prompts designed to elicit active activities or (2) explanations that were reduced by inferences and inference prompts designed to engage learners in constructing the withheld information. Furthermore, in order to explore how interactive learning activities can be elicited, we gave the learners who had difficulties in constructing the prompted inferences adapted remedial explanations with either (3) unspecific engaging prompts or (4) revision prompts. In support of the active < constructive learning hypothesis, we found that the learners who received reduced explanations and inference prompts outperformed the learners who received complete explanations and engaging prompts. Moreover, revision prompts were more effective in eliciting interactive learning activities than engaging prompts. In Experiment 2, N = 40 students were randomly assigned to either (1) a reduced explanations and inference prompts or (2) a reduced explanations and inference prompts plus adapted remedial explanations and revision prompts condition. In support of the constructive < interactive

  1. The Effects of Personal Construct Group Therapy on Breast Cancer Survivors

    ERIC Educational Resources Information Center

    Lane, Lisbeth G.; Viney, Linda L.

    2005-01-01

    In this study, the authors evaluated the effects of a brief personal construct group therapy on breast cancer survivors (N = 42) randomly assigned to either the treatment or wait-list control condition. The Gottschalk Gleser Content Analysis Scales were used to measure the effects for group across time (preand posttreatment, pretreatment, and…

  2. Ecological effects of feral biofuel crops in constructed oak savannah communities

    EPA Science Inventory

    The effects of elevated temperatures and drought on constructed oak savannahs were studied to determine the interactive effects of potentially invasive feral biofuel species and climate change on native grassland communities. A total of 12 sunlit mesocosm were used. Each mesoco...

  3. Ecological effects of feral biofuel crops in constructed oak savannah communities - June 2012

    EPA Science Inventory

    The effects of elevated temperatures and drought on constructed oak savannahs were studied to determine the interactive effects of potentially invasive feral biofuel species and climate change on native grassland communities. A total of 12 sunlit mesocosm were used. Each mesoco...

  4. Comparison of Approaches to Constructing Confidence Intervals for Mediating Effects Using Structural Equation Models

    ERIC Educational Resources Information Center

    Cheung, Mike W. L.

    2007-01-01

    Mediators are variables that explain the association between an independent variable and a dependent variable. Structural equation modeling (SEM) is widely used to test models with mediating effects. This article illustrates how to construct confidence intervals (CIs) of the mediating effects for a variety of models in SEM. Specifically, mediating…

  5. The antinociceptive effect of some Egyptian medicinal plant extracts.

    PubMed

    Atta, A H; Abo EL-Sooud, K

    2004-12-01

    The antinociceptive effect of methanolic extracts (200 and 400 mg kg(-1)) of eight Egyptian medicinal plants was studied using acetic acid-induced writhing and tail-flick test in mice. Oral administration of 400 mg kg(-1) methanolic extracts of Convolvulus fatmensis, Alhagi maurorum, Plantago major seeds, Conyza dioscaridis significantly (P < 0.05) inhibited the nociception to acetic acid-induced writhes with a protection of 85.5-61.3%. Schouwia thebaica, Diplotaxis acris, Plantago major leaves and Mentha microphylla, in the large dose, showed a protection of 50.8-45.8%, which were significantly different as compared to control. The smaller dose of the tested plant extracts did not protect animals from painful acetic acid stimulation with the exception of Alhagi maurorum. In the tail-flick test, methanolic extracts of Mentha microphylla, Conyza dioscaridis, Alhagi maurorum, Plantago major leaves, Diplotaxis acris and Convolvulus fatmensis in a dose of 400 mg kg(-1) produced significant increase in the latency to response of tail to thermal stimulation. Mild or no effect was observed by the small dose with the exception of Diplotaxis acris that had significant antinociceptive effect at the dose of 200 mg kg(-1). The extracts of all tested plants in doses up to 2 g kg(-1) b.wt. did not cause any deaths or major signs of acute toxicity. Phytochemical screening indicated the presence of unsaturated sterols, triterpenes, tannins, flavonoids and carbohydrates and/or glycosides as major constituents. PMID:15507342

  6. Selective Effect of Pesticides on Plant--A Review.

    PubMed

    Parween, Talat; Jan, Sumira; Mahmooduzzafar, Sumira; Fatma, Tasneem; Siddiqui, Zahid Hameed

    2016-01-01

    This review represents systematic and integrated picture of pesticide exposure to plant and its effect on growth and metabolism. Decades ago, agrochemicals were introduced aiming at enhancing crop yields and protecting crops from pests. Due to adaptation and resistance developed by pests to chemicals, every year higher amounts and new chemical compounds are used to protect crops, causing undesired side effects and raising the costs of food production. Biological chemical free agriculture is gaining also more and more support but it is still not able to respond to the need for producing massive amounts of food. The use of agrochemicals, including pesticides, remains a common practice especially in tropical regions and South countries. Cheap compounds, such as DDT, HCH, and Lindane, that are environmentally persistent, are today banned from agriculture use in developed countries, but remain popular in developing countries. As a consequence, persistent residues of these chemicals contaminate food and disperse in the environment. Therefore, the thrust of this paper was to review the application of pesticides effect early from germination to growth of the plant, leading to alteration in biochemical, physiological and different enzymatic and non-enzymatic antioxidants which ultimately affect the yield and resulted in residues in plant, vegetables, and fruits. PMID:25216296

  7. Selective Effect of Pesticides on Plant--A Review.

    PubMed

    Parween, Talat; Jan, Sumira; Mahmooduzzafar, Sumira; Fatma, Tasneem; Siddiqui, Zahid Hameed

    2016-01-01

    This review represents systematic and integrated picture of pesticide exposure to plant and its effect on growth and metabolism. Decades ago, agrochemicals were introduced aiming at enhancing crop yields and protecting crops from pests. Due to adaptation and resistance developed by pests to chemicals, every year higher amounts and new chemical compounds are used to protect crops, causing undesired side effects and raising the costs of food production. Biological chemical free agriculture is gaining also more and more support but it is still not able to respond to the need for producing massive amounts of food. The use of agrochemicals, including pesticides, remains a common practice especially in tropical regions and South countries. Cheap compounds, such as DDT, HCH, and Lindane, that are environmentally persistent, are today banned from agriculture use in developed countries, but remain popular in developing countries. As a consequence, persistent residues of these chemicals contaminate food and disperse in the environment. Therefore, the thrust of this paper was to review the application of pesticides effect early from germination to growth of the plant, leading to alteration in biochemical, physiological and different enzymatic and non-enzymatic antioxidants which ultimately affect the yield and resulted in residues in plant, vegetables, and fruits.

  8. Radioactive Air Emission Notice of Construction for (NOC) Plutonium Finishing Plant (PFP) Project W-460 Plutonium Stabilization and Handling

    SciTech Connect

    JANSKY, M.T.

    2000-03-01

    The following description and any attachments and references are provided to the Washington State Department of Health (WDOH), Division of Radiation Protection, Air Emissions & Defense Waste Section as a notice of construction (NOC) in accordance with Washington Administrative Code (WAC) 246-247, Radiation Protection-Air Emissions. The WAC 246-247-060, ''Applications, registration, and licensing'', states ''This section describes the information requirements for approval to construct, modify, and operate an emission unit. Any NOC requires the submittal of information listed in Appendix A,'' Appendix A (WAC 246-247-1 IO) lists the requirements that must be addressed. Additionally, the following description, attachments, and references are provided to the U.S. Environmental Protection Agency (EPA) as an NOC, in accordance with Title 40 Code of Federal Regulations (CFR), Part 61, ''National Emission Standards for Hazardous Air Pollutants.'' The information required for submittal to the EPA is specified in 40 CFR 61.07. The potential emissions from this activity are estimated to provide greater than 0.1 millirem year total effective dose equivalent (TEDE) to the hypothetical offsite maximally exposed individual (MEI) and commencement is needed within a short time. Therefore, this application also is intended to provide notification of the anticipated date of initial startup in accordance with the requirement listed in 40 CFR 61.09(a)(1), and it is requested that approval of this application also constitutes EPA acceptance of this initial startup notification. Written notification of the actual date of initial startup, in accordance with the requirement listed in 40 CFR 61.09(a)(2), will be provided later. This NOC covers the activities associated with the construction and operation activities involving stabilization and/or repackaging of plutonium in the 2736-ZB Building. An operations support trailer will be installed in the proximity of the 2736-ZB Building. A new

  9. Radioactive Air Emission Notice of Construction (NOC) for Plutonium Finishing Plant (PFP) Project W-460 Plutonium Stabilization and Handling

    SciTech Connect

    JANSKY, M.T.

    2000-05-01

    The following description and any attachments and references are provided to the Washington State Department of Health (WDOH), Division of Radiation Protection, Air Emissions & Defense Waste Section as a notice of construction (NOC) in accordance with Washington Administrative Code (WAC) 246-247, Radiation Protection-Air Emissions. The WAC 246-247-060, ''Applications, registration, and licensing'', states ''This section describes the information requirements for approval to construct, modify, and operate an emission unit. Any NOC requires the submittal of information listed in Appendix A.'' Additionally, the following description, attachments, and references are provided to the US Environmental Protection Agency (EPA) as an NOC, in accordance with Title 40 Code of Federal Regulations (CFR), Part 61, ''National Emission Standards for Hazardous Air Pollutants''. The information required for submittal to the EPA is specified in 40 CFR 61.07. The potential emissions from this activity are estimated to provide greater than 0.1 millirem year total effective dose equivalent (TEDE) to the hypothetical offsite maximally exposed individual (MEI) and commencement is needed within a short time. Therefore, this application also is intended to provide notification of the anticipated date of initial startup in accordance with the requirement listed in 40 CFR 61.09(a)(1), and it is requested that approval of this application also constitutes EPA acceptance of this initial startup notification. Written notification of the actual date of initial startup, in accordance with the requirement listed in 40 CFR 61.09(a)(2), will be provided later. This NOC covers the activities associated with the construction and operation activities involving stabilization and/or repackaging of plutonium in the 2736-ZB Building. A new exhaust stack will be built and operated at the 2736-ZB Building to handle the effluents associated with the operation of the stabilization and repackaging process

  10. The effect of constructing versus solving virtual patient cases on transfer of learning: a randomized trial.

    PubMed

    Tolsgaard, Martin G; Jepsen, Rikke M H G; Rasmussen, Maria B; Kayser, Lars; Fors, Uno; Laursen, Lars C; Svendsen, Jesper H; Ringsted, Charlotte

    2016-02-01

    The purpose of this study was to explore the effect of actively constructing virtual patient (VP) cases compared with solving VP cases on knowledge gains, skills transfer and time spent on cases. Forty-five fourth-year medical students were randomized to constructing (VP-construction, n = 23) or solving (VP-solving, n = 22) four cardiopulmonary VP cases. Whereas the VP-solving group solved the cases, the VP-construction group only received the final diagnosis and had to complete the history, physical findings, and lab results. After a week, participants completed a transfer test involving two standardized patients representing cardiopulmonary cases. Performances on the transfer test were video-recorded and assessed by two blinded raters using the Reporter, Interpreter, Manager, Educator (RIME) framework. Thirty-nine participants completed the transfer test. The VP-construction group spent significantly more time on the VP cases compared with the VP-solving group, p = 0.002. There were no significant differences in RIME scores between the VP-construction group and VP-solving group, p = 0.54.In conclusion, engaging novice students in active VP case construction may be more time consuming than solving VP cases, without resulting in superior skills transfer. PMID:26754313

  11. Effects of light on the gravitropic response in plants.

    NASA Astrophysics Data System (ADS)

    Sakai, T.; Suzuki, G.; Ohgishi, M.; Saji, K.; Okada, K.

    Plants show changing of growth pattern responding to the environmental stimuli to adapt themselves to the environment. Our research purpose is to elucidate the function of genes participating in light-induced change of growth and movement in plants. By isolation and analyses of mutants showing defects in light-induced responses in model plants, Arabidopsis thaliana, genes involved in the response are identified. Previous studies reported that the negative gravitropic response in hypocotyl of Arabidopsis is suppressed by red light irradiation. We isolated a red-light hypersensitive mutant, flabby, which shows a random-hypocotyl bending by red light irradiation. The FLABBY gene encodes a protein, which is involved in the auxin transport in hypocotyls. On the other hand, our recent analysis showed that cryptochromes also induce a blue-light dependent, random-hypocotyl bending in the phototropins-defective mutants. Now we are studying on the genetic interactions between FLABBY and photoreceptors (phytochromes, cryptochromes, and phototropins). We discuss the effects of light on the gravitropic response in plants.

  12. Detailed deposition density maps constructed by large-scale soil sampling for gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Saito, Kimiaki; Tanihata, Isao; Fujiwara, Mamoru; Saito, Takashi; Shimoura, Susumu; Otsuka, Takaharu; Onda, Yuichi; Hoshi, Masaharu; Ikeuchi, Yoshihiro; Takahashi, Fumiaki; Kinouchi, Nobuyuki; Saegusa, Jun; Seki, Akiyuki; Takemiya, Hiroshi; Shibata, Tokushi

    2015-01-01

    Soil deposition density maps of gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant (NPP) accident were constructed on the basis of results from large-scale soil sampling. In total 10,915 soil samples were collected at 2168 locations. Gamma rays emitted from the samples were measured by Ge detectors and analyzed using a reliable unified method. The determined radioactivity was corrected to that of June 14, 2011 by considering the intrinsic decay constant of each nuclide. Finally the deposition maps were created for (134)Cs, (137)Cs, (131)I, (129m)Te and (110m)Ag. The radioactivity ratio of (134)Cs-(137)Cs was almost constant at 0.91 regardless of the locations of soil sampling. The radioactivity ratios of (131)I and (129m)Te-(137)Cs were relatively high in the regions south of the Fukushima NPP site. Effective doses for 50 y after the accident were evaluated for external and inhalation exposures due to the observed radioactive nuclides. The radiation doses from radioactive cesium were found to be much higher than those from the other radioactive nuclides. PMID:24703526

  13. Treatment of a sulfate-rich groundwater contaminated with perchloroethene in a hydroponic plant root mat filter and a horizontal subsurface flow constructed wetland at pilot-scale.

    PubMed

    Chen, Zhongbing; Kuschk, Peter; Paschke, Heidrun; Kästner, Matthias; Müller, Jochen A; Köser, Heinz

    2014-12-01

    A hydroponic plant root mat filter (HPRMF) was compared over 7months with a horizontal subsurface flow constructed wetland (HSSF CW) regarding the removal of perchloroethene (PCE) (about 2 mg L(-1)) from a sulfate- (850 mg L(-1)) and ammonia-rich (50 mg L(-1)) groundwater with a low TOC content. At a mean area specific inflow PCE load of 56 mg m(-2)d(-1), after 4m from inlet, the mean PCE removal during summer time reached 97% in the HPRMF and almost 100% in the HSSF CW. Within the first 2m in the HSSF CW metabolites like dichloroethenes, vinyl chloride and ethene accumulated, their concentrations decreased further along the flow path. Moreover, the tidal operation (a 7-d cycle) in the HSSFCW decreased the accumulation of PCE metabolites within the first 1m of the bed. The carcinogenic degradation metabolite vinyl chloride was not detected in the HPRMF. The smaller accumulation of the degradation metabolites in the HPRMF correlated with its higher redox potential. It can be concluded from this study that HPRMF appears an interesting alternative for special water treatment tasks and that tidal operation will show some positive effects on the removal of the accumulated PCE metabolites in HSSF CW.

  14. Detailed deposition density maps constructed by large-scale soil sampling for gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Saito, Kimiaki; Tanihata, Isao; Fujiwara, Mamoru; Saito, Takashi; Shimoura, Susumu; Otsuka, Takaharu; Onda, Yuichi; Hoshi, Masaharu; Ikeuchi, Yoshihiro; Takahashi, Fumiaki; Kinouchi, Nobuyuki; Saegusa, Jun; Seki, Akiyuki; Takemiya, Hiroshi; Shibata, Tokushi

    2015-01-01

    Soil deposition density maps of gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant (NPP) accident were constructed on the basis of results from large-scale soil sampling. In total 10,915 soil samples were collected at 2168 locations. Gamma rays emitted from the samples were measured by Ge detectors and analyzed using a reliable unified method. The determined radioactivity was corrected to that of June 14, 2011 by considering the intrinsic decay constant of each nuclide. Finally the deposition maps were created for (134)Cs, (137)Cs, (131)I, (129m)Te and (110m)Ag. The radioactivity ratio of (134)Cs-(137)Cs was almost constant at 0.91 regardless of the locations of soil sampling. The radioactivity ratios of (131)I and (129m)Te-(137)Cs were relatively high in the regions south of the Fukushima NPP site. Effective doses for 50 y after the accident were evaluated for external and inhalation exposures due to the observed radioactive nuclides. The radiation doses from radioactive cesium were found to be much higher than those from the other radioactive nuclides.

  15. Effects of coal-fired thermal power plant discharges on agricultural soil and crop plants

    SciTech Connect

    Ajmal, M.; Khan, M.A.

    1986-04-01

    The physicochemical properties of the upstream and downstream waters from the Upper Ganga canal, discharged cooling tower water, machine washings, and scrubber and bottom ash effluents of a 530 MW Kasimpur coal-fired thermal power plant have been determined, and their effects directly on fertile soil and indirectly on pea (Pisum sativam) and wheat (Triticum aestivum) crops have also been studied. The effluents were alkaline in nature. The scrubber and bottom ash effluent contained large amounts of solids and had high biochemical and chemical oxygen demands. The soils irrigated with the different effluents exhibited an increase in pH, organic matter, calcium carbonate, water-soluble salts, cation exchange capacity, electrical conductivity, and nitrogen and phosphorus contents while potassium content decreased. The effects of 100, 50, and 0% (tap water control) dilutions of cooling tower, machine washings, and scrubber and bottom ash effluents on the germination and growth of pea and wheat crops were also monitored. Using the undiluted effluents, there was 100% germination for both crops when irrigation was done with cooling tower effluent. Germination was restricted to 90% for the two crops when irrigated with machine washings effluent, and to 80 and 70% for pea and wheat, respectively, when irrigated with scrubber and bottom ash effluent. Samples of upstream and downstream canal water were also used for irrigating soils with and without crop plants in order to ascertain the impact of effluents on canal water and its subsequent effect on crops. The soils irrigated with downstream canal water were found to contain slightly more calcium carbonate, phosphorus, and ammonia-nitrogen than those receiving upstream canal water. Though 100% germination was obtained in both cases, the growth of plants irrigated with the downstream canal water was slightly reduced.

  16. Effects of phylogeny, leaf traits, and the altitudinal distribution of host plants on herbivore assemblages on congeneric Acer species.

    PubMed

    Nakadai, Ryosuke; Murakami, Masashi; Hirao, Toshihide

    2014-08-01

    Historical, niche-based, and stochastic processes have been proposed as the mechanisms that drive community assembly. In plant-herbivore systems, these processes can correspond to phylogeny, leaf traits, and the distribution of host plants, respectively. Although patterns of herbivore assemblages among plant species have been repeatedly examined, the effects of these factors among co-occurring congeneric host plant species have rarely been studied. Our aim was to reveal the process of community assembly for herbivores by investigating the effects of phylogeny, leaf traits, and the altitudinal distribution of closely related host plants of the genus Acer. We sampled leaf functional traits for 30 Acer species in Japan. Using a newly constructed phylogeny, we determined that three of the six measured leaf traits (leaf thickness, C/N ratio, and condensed tannin content) showed a phylogenetic signal. In a field study, we sampled herbivore communities on 14 Acer species within an elevation gradient and examined relationships between herbivore assemblages and host plants. We found that herbivore assemblages were significantly correlated with phylogeny, leaf traits, phylogenetic signals, and the altitudinal distribution of host plants. Our results indicate that the interaction between historical and current ecological processes shapes herbivore community assemblages.

  17. Ecological and evolutionary consequences of niche construction for its agent.

    PubMed

    Kylafis, Grigoris; Loreau, Michel

    2008-10-01

    Niche construction can generate ecological and evolutionary feedbacks that have been underinvestigated so far. We present an eco-evolutionary model that incorporates the process of niche construction to reveal its effects on the ecology and evolution of the niche-constructing agent. We consider a simple plant-soil nutrient ecosystem in which plants have the ability to increase the input of inorganic nutrient as an example of positive niche construction. On an ecological time scale, the model shows that niche construction allows the persistence of plants under infertile soil conditions that would otherwise lead to their extinction. This expansion of plants' niche, however, requires a high enough rate of niche construction and a high enough initial plant biomass to fuel the positive ecological feedback between plants and their soil environment. On an evolutionary time scale, we consider that the rates of niche construction and nutrient uptake coevolve in plants while a trade-off constrains their values. Different evolutionary outcomes are possible depending on the shape of the trade-off. We show that niche construction results in an evolutionary feedback between plants and their soil environment such that plants partially regulate soil nutrient content. The direct benefit accruing to plants, however, plays a crucial role in the evolutionary advantage of niche construction.

  18. Divergent composition but similar function of soil food webs of individual plants: plant species and community effects.

    PubMed

    Bezemer, T M; Fountain, M T; Barea, J M; Christensen, S; Dekker, S C; Duyts, H; van Hal, R; Harvey, J A; Hedlund, K; Maraun, M; Mikola, J; Mladenov, A G; Robin, C; de Ruiter, P C; Scheu, S; Setälä, H; Smilauer, P; van der Putten, W H

    2010-10-01

    Soils are extremely rich in biodiversity, and soil organisms play pivotal roles in supporting terrestrial life, but the role that individual plants and plant communities play in influencing the diversity and functioning of soil food webs remains highly debated. Plants, as primary producers and providers of resources to the soil food web, are of vital importance for the composition, structure, and functioning of soil communities. However, whether natural soil food webs that are completely open to immigration and emigration differ underneath individual plants remains unknown. In a biodiversity restoration experiment we first compared the soil nematode communities of 228 individual plants belonging to eight herbaceous species. We included grass, leguminous, and non-leguminous species. Each individual plant grew intermingled with other species, but all plant species had a different nematode community. Moreover, nematode communities were more similar when plant individuals were growing in the same as compared to different plant communities, and these effects were most apparent for the groups of bacterivorous, carnivorous, and omnivorous nematodes. Subsequently, we analyzed the composition, structure, and functioning of the complete soil food webs of 58 individual plants, belonging to two of the plant species, Lotus corniculatus (Fabaceae) and Plantago lanceolata (Plantaginaceae). We isolated and identified more than 150 taxa/groups of soil organisms. The soil community composition and structure of the entire food webs were influenced both by the species identity of the plant individual and the surrounding plant community. Unexpectedly, plant identity had the strongest effects on decomposing soil organisms, widely believed to be generalist feeders. In contrast, quantitative food web modeling showed that the composition of the plant community influenced nitrogen mineralization under individual plants, but that plant species identity did not affect nitrogen or carbon

  19. Divergent composition but similar function of soil food webs of individual plants: plant species and community effects.

    PubMed

    Bezemer, T M; Fountain, M T; Barea, J M; Christensen, S; Dekker, S C; Duyts, H; van Hal, R; Harvey, J A; Hedlund, K; Maraun, M; Mikola, J; Mladenov, A G; Robin, C; de Ruiter, P C; Scheu, S; Setälä, H; Smilauer, P; van der Putten, W H

    2010-10-01

    Soils are extremely rich in biodiversity, and soil organisms play pivotal roles in supporting terrestrial life, but the role that individual plants and plant communities play in influencing the diversity and functioning of soil food webs remains highly debated. Plants, as primary producers and providers of resources to the soil food web, are of vital importance for the composition, structure, and functioning of soil communities. However, whether natural soil food webs that are completely open to immigration and emigration differ underneath individual plants remains unknown. In a biodiversity restoration experiment we first compared the soil nematode communities of 228 individual plants belonging to eight herbaceous species. We included grass, leguminous, and non-leguminous species. Each individual plant grew intermingled with other species, but all plant species had a different nematode community. Moreover, nematode communities were more similar when plant individuals were growing in the same as compared to different plant communities, and these effects were most apparent for the groups of bacterivorous, carnivorous, and omnivorous nematodes. Subsequently, we analyzed the composition, structure, and functioning of the complete soil food webs of 58 individual plants, belonging to two of the plant species, Lotus corniculatus (Fabaceae) and Plantago lanceolata (Plantaginaceae). We isolated and identified more than 150 taxa/groups of soil organisms. The soil community composition and structure of the entire food webs were influenced both by the species identity of the plant individual and the surrounding plant community. Unexpectedly, plant identity had the strongest effects on decomposing soil organisms, widely believed to be generalist feeders. In contrast, quantitative food web modeling showed that the composition of the plant community influenced nitrogen mineralization under individual plants, but that plant species identity did not affect nitrogen or carbon

  20. Essential roles and hazardous effects of nickel in plants.

    PubMed

    Ahmad, Muhammad Sajid Aqeel; Ashraf, Muhammad

    2011-01-01

    With the world's ever increasing human population, the issues related to environmental degradation of toxicant chemicals are becoming more serious. Humans have accelerated the emission to the environment of many organic and inorganic pollutants such as pesticides, salts, petroleum products, acids, heavy metals, etc. Among different environmental heavy-metal pollutants, Ni has gained considerable attention in recent years, because of its rapidly increasing concentrations in soil, air, and water in different parts of the world. The main mechanisms by which Ni is taken up by plants are passive diffusion and active transport. Soluble Ni compounds are preferably absorbed by plants passively, through a cation transport system; chelated Ni compounds are taken up through secondary, active-transport-mediated means, using transport proteins such as permeases. Insoluble Ni compounds primarily enter plant root cells through endocytosis. Once absorbed by roots, Ni is easily transported to shoots via the xylem through the transpiration stream and can accumulate in neonatal parts such as buds, fruits, and seeds. The Ni transport and retranslocation processes are strongly regulated by metal-ligand complexes (such as nicotianamine, histidine, and organic acids) and by some proteins that specifically bind and transport Ni. Nickel, in low concentrations, fulfills a variety of essential roles in plants, bacteria, and fungi. Therefore, Ni deficiency produces an array of effects on growth and metabolism of plants, including reduced growth, and induction of senescence, leaf and meristem chlorosis, alterations in N metabolism, and reduced Fe uptake. In addition, Ni is a constituent of several metallo-enzymes such as urease, superoxide dismutase, NiFe hydrogenases, methyl coenzyme M reductase, carbon monoxide dehydrogenase, acetyl coenzyme-A synthase, hydrogenases, and RNase-A. Therefore, Ni deficiencies in plants reduce urease activity, disturb N assimilation, and reduce scavenging of

  1. Early herbivore alert matters: plant-mediated effects of egg deposition on higher trophic levels benefit plant fitness.

    PubMed

    Pashalidou, Foteini G; Frago, Enric; Griese, Eddie; Poelman, Erik H; van Loon, Joop J A; Dicke, Marcel; Fatouros, Nina E

    2015-09-01

    Induction of plant defences, specifically in response to herbivore attack, can save costs that would otherwise be needed to maintain defences even in the absence of herbivores. However, plants may suffer considerable damage during the time required to mount these defences against an attacker. This could be resolved if plants could respond to early cues, such as egg deposition, that reliably indicate future herbivory. We tested this hypothesis in a field experiment and found that egg deposition by the butterfly Pieris brassicae on black mustard (Brassica nigra) induced a plant response that negatively affected feeding caterpillars. The effect cascaded up to the third and fourth trophic levels (larval parasitoids and hyperparasitoids) by affecting the parasitisation rate and parasitoid performance. Overall, the defences induced by egg deposition had a positive effect on plant seed production and may therefore play an important role in the evolution of plant resistance to herbivores. PMID:26147078

  2. Constructing more informative plant–pollinator networks: visitation and pollen deposition networks in a heathland plant community

    PubMed Central

    Ballantyne, G.; Baldock, Katherine C. R.; Willmer, P. G.

    2015-01-01

    Interaction networks are widely used as tools to understand plant–pollinator communities, and to examine potential threats to plant diversity and food security if the ecosystem service provided by pollinating animals declines. However, most networks to date are based on recording visits to flowers, rather than recording clearly defined effective pollination events. Here we provide the first networks that explicitly incorporate measures of pollinator effectiveness (PE) from pollen deposition on stigmas per visit, and pollinator importance (PI) as the product of PE and visit frequency. These more informative networks, here produced for a low diversity heathland habitat, reveal that plant–pollinator interactions are more specialized than shown in most previous studies. At the studied site, the specialization index was lower for the visitation network than the PE network, which was in turn lower than for the PI network. Our study shows that collecting PE data is feasible for community-level studies in low diversity communities and that including information about PE can change the structure of interaction networks. This could have important consequences for our understanding of threats to pollination systems. PMID:26336181

  3. Trickle water and feeding system in plant culture and light-dark cycle effects on plant growth

    NASA Technical Reports Server (NTRS)

    Takano, T.; Inada, K.; Takanashi, J.

    1987-01-01

    Rockwool, as an inert medium covered or bagged with polyethylene film, can be effectively used for plant culture in space stations. The most important machine is the pump adjusting the dripping rate in the feeding system. Hydro-aeroponics may be adaptable to a space laboratory. The shortening of the light-dark cycles inhibits plant growth and induces an abnormal morphogenesis. A photoperiod of 12 hr dark may be needed for plant growth.

  4. Trickle water and feeding system in plant culture and light-dark cycle effects on plant growth

    NASA Astrophysics Data System (ADS)

    Takano, T.; Inada, K.; Takanashi, J.

    Rockwool, as an inert medium covered or bagged with polyethylene film, can be effectively used for plant culture in space station. The most important machine is the pump adjusting the dripping rate in the feeding system. Hydro-aeroponics may be adaptable to a space laboratory. The shortening of the light-dark cycles inhibits plant growth and induces an abnormal morphogenesis. A photoperiod of 12-hr-dark may be needed for plant growth.

  5. Trickle water and feeding system in plant culture and light-dark cycle effects on plant growth.

    PubMed

    Takano, T; Inada, K; Takanashi, J

    1987-01-01

    Rockwool, as an inert medium covered or bagged with polyethylene film, can be effectively used for plant culture in space station. The most important machine is the pump adjusting the dripping rate in the feeding system. Hydro-aeroponics may be adaptable to a space laboratory. The shortening of the light-dark cycles inhibits plant growth and induces an abnormal morphogenesis. A photoperiod of 12-hr-dark may be needed for plant growth. PMID:11537264

  6. A natural plant growth promoter calliterpenone from a plant Callicarpa macrophylla Vahl improves the plant growth promoting effects of plant growth promoting rhizobacteria (PGPRs).

    PubMed

    Maji, Deepamala; Barnawal, Deepti; Gupta, Aakansha; King, Shikha; Singh, A K; Kalra, A

    2013-05-01

    Experiments were conducted to evaluate the efficacy of calliterpenone, a natural plant growth promoter from a shrub Callicarpa macrophylla Vahl., in enhancing the growth and yield promoting effects of plant growth promoting rhizobacteria (PGPRs), in menthol mint (Mentha arvensis L).This study is based on our previous results indicating the microbial growth promotion by calliterpenone and assumption that application of calliterpenone along with PGPRs will improve the population of PGPRs resulting in higher impacts on plant growth and yield. Of the 15 PGPRs (identified as potent ones in our laboratory), 25 μl of 0.01 mM calliterpenone (8.0 μg/100 ml) was found to be useful in improving the population of nine PGPRs in culture media. The five selected strains of PGPRs exhibiting synergy with calliterpenone in enhancing growth of maize compared to PGPR or calliterpenone alone were selected and tested on two cultivars (cvs. Kosi and Kushal) of M. arvensis. Of the five strains, Bacillus subtilis P-20 (16S rDNA sequence homologous to Accession No NR027552) and B. subtilis Daz-26 (16SrDNA sequence homologuos to Accession No GU998816) were found to be highly effective in improving the herb and essential oil yield in the cultivars Kushal and Kosi respectively when co-treated with calliterpenone. The results open up the possibilities of using a natural growth promoter along with PGPRs as a bio-agri input for sustainable and organic agriculture.

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

    NASA Astrophysics Data System (ADS)

    Mudrák, Obdřej; 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

  8. CO2 EFFECTS ON MOJAVE DESERT PLANT INTERACTIONS

    SciTech Connect

    L. A. DEFALCO; G. C. FERNANDEZ; S. D. SMITH; R. S. NOWAK

    2004-01-01

    Seasonal and interannual droughts characteristic of deserts have the potential to modify plant interactions as atmospheric CO{sub 2} concentrations continue to rise. At the Nevada Desert FACE (free-air CO{sub 2} enrichment) facility in the northern Mojave Desert, the effects of elevated atmospheric C02 (550 vs. ambient {approx}360 {micro}mol mol{sup -1}) on plant interactions were examined during two years of high and low rainfall. Results suggest that CO{sub 2} effects on the interaction between native species and their understory herbs are dependent on the strength of competition when rainfall is plentiful, but are unimportant during annual drought. Seasonal rainfall for 1999 was 23% the long-term average for the area, and neither elevated CO{sub 2} nor the low production of herbaceous neighbors had an effect on relative growth rate (RGR, d{sup -1}) and reproductive effort (RE, number of flowers g{sup -1}) for Achnatherum hymenoides (early season perennial C{sub 3} grass), Pleuraphis rigida (late season perennial C{sub 4} grass), and Larrea tridentata (evergreen C{sub 3} shrub). In contrast, 1998 received 213% the average rainfall. Consequently, the decrease in RGR and increase in RE for Achnatherum, whose period of growth overlaps directly with that of its neighbors, was exaggerated at elevated CO{sub 2}. However, competitive effects of neighbors on Eriogonum trichopes (a winter annual growing in shrub interspaces), Pleuraphis and Larrea were not affected by elevated CO{sub 2}, and possible explanations are discussed. Contrary to expectations, the invasive annual neighbor Bromus madritensis ssp. rubens had little influence on target plant responses because densities in 1998 and 1999 at this site were well below those found in other studies where it has negatively affected perennial plant growth. The extent that elevated CO{sub 2} reduces the performance of Achnatherum in successive years to cause its loss from the plant community depends more on future pressure

  9. Plant potassium content modifies the effects of arbuscular mycorrhizal symbiosis on root hydraulic properties in maize plants.

    PubMed

    El-Mesbahi, Mohamed Najib; Azcón, Rosario; Ruiz-Lozano, Juan Manuel; Aroca, Ricardo

    2012-10-01

    It is well known that the arbuscular mycorrhizal (AM) symbiosis helps the host plant to overcome several abiotic stresses including drought. One of the mechanisms for this drought tolerance enhancement is the higher water uptake capacity of the mycorrhizal plants. However, the effects of the AM symbiosis on processes regulating root hydraulic properties of the host plant, such as root hydraulic conductivity and plasma membrane aquaporin gene expression, and protein abundance, are not well defined. Since it is known that K(+) status is modified by AM and that it regulates root hydraulic properties, it has been tested how plant K(+) status could modify the effects of the symbiosis on root hydraulic conductivity and plasma membrane aquaporin gene expression and protein abundance, using maize (Zea mays L.) plants and Glomus intraradices as a model. It was observed that the supply of extra K(+) increased root hydraulic conductivity only in AM plants. Also, the different pattern of plasma membrane aquaporin gene expression and protein abundance between AM and non-AM plants changed with the application of extra K(+). Thus, plant K(+) status could be one of the causes of the different observed effects of the AM symbiosis on root hydraulic properties. The present study also highlights the critical importance of AM fungal aquaporins in regulating root hydraulic properties of the host plant. PMID:22370879

  10. 10 CFR Appendix N to Part 50 - Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites Section 101... nuclear power reactors of essentially the same design to be located at different sites. 1 1 If the...

  11. 10 CFR Appendix N to Part 50 - Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites Section 101... nuclear power reactors of essentially the same design to be located at different sites. 1 1 If the...

  12. 10 CFR Appendix N to Part 50 - Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites Section 101... nuclear power reactors of essentially the same design to be located at different sites. 1 1 If the...

  13. 10 CFR Appendix N to Part 50 - Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites Section 101... nuclear power reactors of essentially the same design to be located at different sites. 1 1 If the...

  14. 10 CFR Appendix N to Part 50 - Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at Multiple Sites Section 101... nuclear power reactors of essentially the same design to be located at different sites. 1 1 If the...

  15. Field application of a planted fixed bed reactor (PFR) for support media and rhizosphere investigation using undisturbed samples from full-scale constructed wetlands.

    PubMed

    Barreto, A B; Vasconcellos, G R; von Sperling, M; Kuschk, P; Kappelmeyer, U; Vasel, J L

    2015-01-01

    This study presents a novel method for investigations on undisturbed samples from full-scale horizontal subsurface-flow constructed wetlands (HSSFCW). The planted fixed bed reactor (PFR), developed at the Helmholtz Center for Environmental Research (UFZ), is a universal test unit for planted soil filters that reproduces the operational conditions of a constructed wetland (CW) system in laboratory scale. The present research proposes modifications on the PFR original configuration in order to allow its operation in field conditions. A mobile device to obtain undisturbed samples from real-scale HSSFCW was also developed. The experimental setting is presented with two possible operational configurations. The first allows the removal and replacement of undisturbed samples in the CW bed for laboratory investigations, guaranteeing sample integrity with a mobile device. The second allows the continuous operation of the PFR and undisturbed samples as a fraction of the support media, reproducing the same environmental conditions outside the real-scale system. Investigations on the hydrodynamics of the adapted PFR were carried out with saline tracer tests, validating the proposed adaptation. Six adapted PFR units were installed next to full-scale HSSFCW beds and fed with interstitial liquid pumped from two regions of planted and unplanted support media. Fourteen points were monitored along the system, covering carbon fractions, nitrogen and sulfate. The results indicate the method as a promising tool for investigations on CW support media, rhizosphere and open space for studies on CW modeling, respirometry, kinetic parameters, microbial communities, redox potential and plant influence on HSSFCW. PMID:26247753

  16. Establishing the effectiveness of patient decision aids: key constructs and measurement instruments

    PubMed Central

    2013-01-01

    Background Establishing the effectiveness of patient decision aids (PtDA) requires evidence that PtDAs improve the quality of the decision-making process and the quality of the choice made, or decision quality. The aim of this paper is to review the theoretical and empirical evidence for PtDA effectiveness and discuss emerging practical and research issues in the measurement of effectiveness. Methods This updated overview incorporates: a) an examination of the instruments used to measure five key decision-making process constructs (i.e., recognize decision, feel informed about options and outcomes, feel clear about goals and preferences, discuss goals and preferences with health care provider, and be involved in decisions) and decision quality constructs (i.e., knowledge, realistic expectations, values-choice agreement) within the 86 trials in the Cochrane review; and b) a summary of the 2011 Cochrane Collaboration’s review of PtDAs for these key constructs. Data on the constructs and instruments used were extracted independently by two authors from the 86 trials and any disagreements were resolved by discussion, with adjudication by a third party where required. Results The 86 studies provide considerable evidence that PtDAs improve the decision-making process and decision quality. A majority of the studies (76/86; 88%) measured at least one of the key decision-making process or decision quality constructs. Seventeen different measurement instruments were used to measure decision-making process constructs, but no single instrument covered all five constructs. The Decisional Conflict Scale was most commonly used (n = 47), followed by the Control Preference Scale (n = 9). Many studies reported one or more constructs of decision quality, including knowledge (n = 59), realistic expectation of risks and benefits (n = 21), and values-choice agreement (n = 13). There was considerable variability in how values-choice agreement was defined and determined. No study

  17. The effects of different plant extracts on nematodes.

    PubMed

    Klimpel, Sven; Abdel-Ghaffar, Fathy; Al-Rasheid, Khaled A S; Aksu, Gülendem; Fischer, Katja; Strassen, Bianca; Mehlhorn, Heinz

    2011-04-01

    The anthelminthic efficacy of some differently obtained extracts of several plants was tested in vivo in laboratory animals and in vitro. The extracts were obtained by ethanolic, methanolic, aqueous, or chloroform, respectively, acetonitrile polyethylenglycol (PEG) and/or propylencarbonate (PC) elution at room temperature or at 37°C. The plants used were bulbs of onions, garlic, chives, coconut, birch tree, ananas, cistrose, banana, chicory, date palm fruit, fig, pumpkin, and neem tree seeds. The worm systems tested both in vivo and in vitro were Trichuris muris and Angiostrongylus cantonensis but only in vivo Toxocara cati. The tests clearly showed that the different extraction methods eluted different components and different mass amounts, which had different efficacies against the above-cited worms. In vitro effects against A. cantonensis and T.muris were best with aqueous extracts, followed by chloroform extracts. The other plant extracts showed only low or no effects on A. cantonensis in vitro. In the case of T. muris, best results were obtained in vivo and in vitro with PEG/PC extracts of the onion followed by the aqueous extract of coconut. The complete elimination of worms in the in vivo experiments with T. muris was obtained when infected mice were treated with a 1:1 mixture of extracts of coconut and onion being produced by elutions with a mixture of 1:1 PEG and PC and fed daily for 8 days. T. cati in a naturally infected cat was eliminated by daily oral application of 6 ml coco's fluid for 5 days. This study shows that a broad spectrum of plants has anti-nematodal activities, the intensity of which, however, depends on the mode of extraction. This implicates that, if results should be really comparable, the same extraction methods at the same temperatures have to be used. Furthermore, efficacy in in vitro systems does not guarantee as good--if at all--efficacy in vivo. PMID:21110041

  18. Radiation effects on organic materials in nuclear plants. Final report

    SciTech Connect

    Bruce, M B; Davis, M V

    1981-11-01

    A literature search was conducted to identify information useful in determining the lowest level at which radiation causes damage to nuclear plant equipment. Information was sought concerning synergistic effects of radiation and other environmental stresses. Organic polymers are often identified as the weak elements in equipment. Data on radiation effects are summarized for 50 generic name plastics and 16 elastomers. Coatings, lubricants, and adhesives are treated as separate groups. Inorganics and metallics are considered briefly. With a few noted exceptions, these are more radiation resistant than organic materials. Some semiconductor devices and electronic assemblies are extremely sensitive to radiation. Any damage threshold including these would be too low to be of practical value. With that exception, equipment exposed to less than 10/sup 4/ rads should not be significantly affected. Equipment containing no Teflon should not be significantly affected by 10/sup 5/ rads. Data concerning synergistic effects and radiation sensitization are discussed. The authors suggest correlations between the two effects.

  19. Herbivore Diet Breadth and Host Plant Defense Mediate the Tri-Trophic Effects of Plant Toxins on Multiple Coccinellid Predators

    PubMed Central

    Katsanis, Angelos; Rasmann, Sergio; Mooney, Kailen A.

    2016-01-01

    Host plant defenses are known to cascade up food chains to influence herbivores and their natural enemies, but how herbivore and predator traits and identity mediate such tri-trophic dynamics is largely unknown. We assessed the influence of plant defense on aphid and coccinellid performance in laboratory trials with low- vs. high-glucosinolate varieties of Brassica napus, a dietary specialist (Brevicoryne brassicae) and generalist (Myzus persicae) aphid, and five species of aphidophagous coccinellids. The performance of the specialist and generalist aphids was similar and unaffected by variation in plant defense. Aphid glucosinolate concentration and resistance to predators differed by aphid species and host plant defense, and these effects acted independently. With respect to aphid species, the dietary generalist aphid (vs. specialist) had 14% lower glucosinolate concentration and coccinellid predators ate three-fold more aphids. With respect to host plant variety, the high-glucosinolate plants (vs. low) increased aphid glucosinolate concentration by 21%, but had relatively weak effects on predation by coccinellids and these effects varied among coccinellid species. In turn, coccinellid performance was influenced by the interactive effects of plant defense and aphid species, as the cascading, indirect effect of plant defense was greater when feeding upon the specialist than generalist aphid. When feeding upon specialist aphids, low- (vs. high-) glucosinolate plants increased coccinellid mass gain by 78% and accelerated development by 14%. In contrast, when feeding upon generalist aphids, low- (vs. high-) glucosinolate plants increased coccinellid mass gain by only 11% and had no detectable effect on development time. These interactive effects of plant defense and aphid diet breadth on predator performance also varied among coccinellid species; the indirect negative effects of plant defenses on predator performance was consistent among the five predators when

  20. Herbivore Diet Breadth and Host Plant Defense Mediate the Tri-Trophic Effects of Plant Toxins on Multiple Coccinellid Predators.

    PubMed

    Katsanis, Angelos; Rasmann, Sergio; Mooney, Kailen A

    2016-01-01

    Host plant defenses are known to cascade up food chains to influence herbivores and their natural enemies, but how herbivore and predator traits and identity mediate such tri-trophic dynamics is largely unknown. We assessed the influence of plant defense on aphid and coccinellid performance in laboratory trials with low- vs. high-glucosinolate varieties of Brassica napus, a dietary specialist (Brevicoryne brassicae) and generalist (Myzus persicae) aphid, and five species of aphidophagous coccinellids. The performance of the specialist and generalist aphids was similar and unaffected by variation in plant defense. Aphid glucosinolate concentration and resistance to predators differed by aphid species and host plant defense, and these effects acted independently. With respect to aphid species, the dietary generalist aphid (vs. specialist) had 14% lower glucosinolate concentration and coccinellid predators ate three-fold more aphids. With respect to host plant variety, the high-glucosinolate plants (vs. low) increased aphid glucosinolate concentration by 21%, but had relatively weak effects on predation by coccinellids and these effects varied among coccinellid species. In turn, coccinellid performance was influenced by the interactive effects of plant defense and aphid species, as the cascading, indirect effect of plant defense was greater when feeding upon the specialist than generalist aphid. When feeding upon specialist aphids, low- (vs. high-) glucosinolate plants increased coccinellid mass gain by 78% and accelerated development by 14%. In contrast, when feeding upon generalist aphids, low- (vs. high-) glucosinolate plants increased coccinellid mass gain by only 11% and had no detectable effect on development time. These interactive effects of plant defense and aphid diet breadth on predator performance also varied among coccinellid species; the indirect negative effects of plant defenses on predator performance was consistent among the five predators when