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 constructed wetland. Key words: clogging; plant root; salt tracers; hydraulic performance; subsurface flow constructed wetlands

  2. Substrate effect on bacterial communities from constructed wetlands planted with Typha latifolia treating industrial wastewater

    Microsoft Academic Search

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

    2009-01-01

    Constructed wetlands (CWs) have been recognized as being able to effectively treat wastewater from municipal and industrial sources. This study focused on the effect of different substrates and long-term operation of horizontal subsurface flow CWs treating tannery wastewater on the bacterial communities. The CWs were planted with Typha latifolia in three types of substrate: two units with different types of

  3. Plant Light Box Construction

    NSDL National Science Digital Library

    The Wisconsin Fast Plants Program

    These instructions describe how to construct a plant light box from two stackable plastic file crates that are cut, lined with aluminum foil and lit with a 40/42-watt CFL bulb. This 3-page document includes a complete materials list and 12-step assembly instructions with photographs that illustrate each step. This light box works well for growing Fast Plants.

  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. PMID:25043825

  5. Effects of plants and microorganisms in constructed wetlands for wastewater treatment

    Microsoft Academic Search

    U. Stottmeister; A. Wießner; P. Kuschk; U. Kappelmeyer; M. Kästner; O. Bederski; R. A. Müller; H. Moormann

    2003-01-01

    Constructed wetlands are a natural alternative to technical methods of wastewater treatment. However, our understanding of the complex processes caused by the plants, microorganisms, soil matrix and substances in the wastewater, and how they all interact with each other, is still rather incomplete.In this article, a closer look will be taken at the mechanisms of both plants in constructed wetlands

  6. Toxicity of high salinity tannery wastewater and effects on constructed wetland plants.

    PubMed

    Calheiros, Cristina S C; Silva, Gabriela; Quitério, Paula V B; Crispim, Luís F C; Brix, Hans; Moura, Sandra C; Castro, Paula M L

    2012-08-01

    The toxicity of high salinity tannery wastewater produced after an activated sludge secondary treatment on the germination and seedling growth of Trifolium pratense, a species used as indicator in toxicity tests, was evaluated. Growth was inhibited by wastewater concentrations >25% and undiluted effluent caused a complete germination inhibition. Constructed wetlands (CWs) with Arundo donax or Sarcocornia fruticosa were envisaged to further polish this wastewater. Selection of plant species to use in CWs for industrial wastewater treatment is an important issue, since for a successful establishment they have to tolerate the often harsh wastewater composition. For that, the effects of this wastewater on the growth of Arundo and Sarcocornia were assessed in pot assays. Plants were subject to different wastewater contents (0/50/100%), and both were resilient to the imposed conditions. Arundo had higher growth rates and biomass than Sarcocornia and may therefore be the preferred species for use in CWs treating tannery wastewater. CWs planted with the above mentioned plants significantly decreased the toxicity of the wastewater, as effluent from the CWs outlet stimulated the growth of Trifolium at concentrations <50%, and seed germination and growth even occurred in undiluted effluent. PMID:22908635

  7. Effects of belowground resource use comlementarity on invasion of constructed grassland plant communities

    Microsoft Academic Search

    Cynthia S. Brown; Kevin J. Rice

    2010-01-01

    At two field sites that differed in fertility, we investigated how species richness, functional group diversity, and species\\u000a composition of constructed plant communities influenced invasion. Grassland communities were constructed to be either functionally\\u000a diverse or functionally simple based on belowground resource use patterns of constituent species. Communities were also constructed\\u000a with different numbers of species (two or five) to examine

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

    SciTech Connect

    Albers, P.H.; Camardese, M.B. (U.S. Fish and Wildlife Service, Laurel, MD (United States). 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.

  9. 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

  10. Mechanism of the effect caused by highway construction on plant biomass in Longitudinal Range-Gorge Region

    NASA Astrophysics Data System (ADS)

    Liu, Jie; Xu, Honglei; Chang, Chunping

    2013-03-01

    Taking Dabao (from Dali City to Baoshan City, Yunnan Province, China) and Sixiao (from Simao City to Xiaomengyang Town, Yunnan Province, China) highways in Longitudinal Range-Gorge Region as examples. Biomass, coverage and photosynthesis rate of different plant types on sampling points (at the distances from road of 5, 20, 40, 80, 120 and 200 m) and their control points were estimated on ground. The relations among biomass, coverage, photosynthesis rate were analyzed with an aim to explore the mechanism of the effect caused by highway construction on plant biomass. The results show, i) the impacts of highway construction on plant biomass are both positive and negative. Arbor is mainly negatively impacted, while shrub and herbage are mainly positively impacted. The effect of highway construction decrease with the increase of distance from the road; ii) highway construction exert obvious influence on plant biomass through altering the physiologic processes (reflected by the plant number) and photosynthesis, iii) highway construction will result in the decrease of arbor number, photosynthesis rate and biomass, and increase of plant number, photosynthesis rate and biomass of shrub and herbage.

  11. 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.

  12. 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...

  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. 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.

  15. 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. PMID:24994107

  16. 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. PMID:24645463

  17. Effects of plant biomass on denitrifying genes in subsurface-flow constructed wetlands.

    PubMed

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

    2014-04-01

    The effect of Typha latifolia and its litter on density and abundance of three denitrifying genes (nirS, nirK and nosZ) were investigated in six laboratory-scale SSF CW microcosms. Results showed that the copy numbers of nirS, nirK and nosZ in wetland microcosms were ranged between 10(8)-10(9), 10(6)-10(7) and 10(7)-10(8) copies g(-1), respectively. The presence of T. latifolia encouraged the growth of nirK containing bacteria. Addition of cattail litter could greatly stimulate the growth of bacteria containing nirS and nosZ gene. Path analysis illustrated that the presence of plants and litters had no significant direct impact on denitrifying genes, while it affected the denitrifying genes via alteration of dissolved oxygen and carbon sources. PMID:24565872

  18. 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 ...

  19. Effect of intermittent operation on contaminant removal and plant growth in vertical flow constructed wetlands: A microcosm experiment

    Microsoft Academic Search

    Wenlin Jia; Jian Zhang; Juan Wu; Huijun Xie; Bo Zhang

    2010-01-01

    The influences of intermittent operation and different length of drying time on contaminant removal as well as wetland plant growth in vertical flow constructed wetlands (VFCWs) were investigated in this study. Microcosm wetlands planted with Phragmites australis were subjected to a 4-month experiment involving different operations (continuously and intermittently flood) and time ratios of flood to drain (F\\/D) with the

  20. 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 (?) 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. PMID:25000198

  1. Toxicity of High Salinity Tannery Wastewater and Effects on Constructed Wetland Plants

    Microsoft Academic Search

    Cristina S. C. Calheiros; Gabriela Silva; Paula V. B. Quitério; Luís F. C. Crispim; Hans Brix; Sandra C. Moura; Paula M. L. Castro

    2012-01-01

    The toxicity of high salinity tannery wastewater produced after an activated sludge secondary treatment on the germination and seedling growth of Trifolium pratense, a species used as indicator in toxicity tests, was evaluated. Growth was inhibited by wastewater concentrations >25% and undiluted effluent caused a complete germination inhibition. Constructed wetlands (CWs) with Arundo donax or Sarcocornia fruticosa were envisaged to

  2. Toxicity of high salinity tannery wastewater and effects on constructed wetland plants

    Microsoft Academic Search

    Cristina S. C. Calheiros; Gabriela Silva; Paula V. B. Quitério; Luís F. C. Crispim; Hans Brix; Sandra C. Moura; Paula M. L. Castro

    2011-01-01

    The toxicity of high salinity tannery wastewater produced after an activated sludge secondary treatment on the germination and seedling growth of Trifolium pratense, a species used as indicator in toxicity tests, was evaluated. Growth was inhibited by wastewater concentrations >25% and undiluted effluent caused a complete germination inhibition. Constructed wetlands (CWs) with Arundo donax or Sarcocornia fruticosa were envisaged to

  3. A review of plant-pharmaceutical interactions: from uptake and effects in crop plants to phytoremediation in constructed wetlands.

    PubMed

    Carvalho, Pedro N; Basto, M Clara P; Almeida, C Marisa R; Brix, Hans

    2014-10-01

    Pharmaceuticals are commonly found both in the aquatic and the agricultural environments as a consequence of the human activities and associated discharge of wastewater effluents to the environment. The utilization of treated effluent for crop irrigation, along with land application of manure and biosolids, accelerates the introduction of these compounds into arable lands and crops. Despite the low concentrations of pharmaceuticals usually found, the continuous introduction into the environment from different pathways makes them 'pseudo-persistent'. Several reviews have been published regarding the potential impact of veterinary and human pharmaceuticals on arable land. However, plant uptake as well as phytotoxicity data are scarcely studied. Simultaneously, phytoremediation as a tool for pharmaceutical removal from soils, sediments and water is starting to be researched, with promising results. This review gives an in-depth overview of the phytotoxicity of pharmaceuticals, their uptake and their removal by plants. The aim of the current work was to map the present knowledge concerning pharmaceutical interactions with plants in terms of uptake and the use of plant-based systems for phytoremediation purposes. PMID:24481515

  4. Effect of earthworm Eisenia fetida and wetland plants on nitrification and denitrification potentials in vertical flow constructed wetland.

    PubMed

    Xu, Defu; Li, Yingxue; Howard, Alan; Guan, Yidong

    2013-06-01

    The response of nitrification potentials, denitrification potentials, and N removal efficiency to the introduction of earthworms and wetland plants in a vertical flow constructed wetland system was investigated. Addition of earthworms increased nitrification and denitrification potentials of substrate in non-vegetated constructed wetland by 236% and 8%, respectively; it increased nitrification and denitrification potentials in rhizosphere in vegetated constructed wetland (Phragmites austrail, Typha augustifolia and Canna indica), 105% and 5%, 187% and 12%, and 268% and 15% respectively. Denitrification potentials in rhizosphere of three wetland plants were not significantly different, but nitrification potentials in rhizosphere followed the order of C. indica>T. augustifolia>P. australis when addition of earthworms into constructed wetland. Addition of earthworms to the vegetated constructed significantly increased the total number of bacteria and fungi of substrates (P<0.05). The total number of bacteria was significantly correlated with nitrification potentials (r=913, P<0.01) and denitrification potentials (r=840, P<0.01), respectively. The N concentration of stems and leaves of C. indica were significantly higher in the constructed wetland with earthworms (P<0.05). Earthworms had greater impact on nitrification potentials than denitrification potentials. The removal efficiency of N was improved via stimulated nitrification potentials by earthworms and higher N uptake by wetland plants. PMID:23591133

  5. 75 FR 32313 - Specifications and Drawings for Construction Direct Buried Plant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ...Service 7 CFR Part 1755 Specifications and Drawings for Construction Direct Buried Plant...Bulletin 1753F- 150, Specifications and Drawings for Construction of Direct Buried Plant...Effective date of Specifications and Drawings final rule]. for Construction of...

  6. CONSTRUCTION OF NUCLEAR POWER PLANTS

    E-print Network

    the Challenges of Climate Change and Sustainability May 8, 2008 ATHENS, GREECE ROBERT E. UHRIG Ph.D., PCONSTRUCTION OF NUCLEAR POWER PLANTS A Workshop on "NUCLEAR ENERGY RENAISSANCE" Addressing ­ Including siting of power plants and transmission lines #12;· YOU WILL NOTE THAT: ­ I DID NOT HAVE TO BUILD

  7. MATERIALS FOR OXYGENATED WASTEWATER TREATMENT PLANT CONSTRUCTION

    EPA Science Inventory

    This research study was initiated to identify resistant materials for construction of wastewater treatment plants using the oxygen activated sludge process. In this investigation, samples of a broad range of construction materials were exposed for periods up to 28 months in the a...

  8. CAD application to power plant design, construction and operation

    SciTech Connect

    Pandya, J.M.; Marinkovich, P.S.; Mysore, R.K.

    1982-05-01

    The nuclear industry, beset with increasing costs of constructing new nuclear plants, needs new initiatives. One, recently developed, is the use of CAD-IGS techniques that are proven beneficial in reducing the construction costs. This methodology had been used successfully in aerospace and automotive industries for many years. Westinghouse CAD-IGS experience with an overseas nuclear plant, now under construction, demonstrates this to be an effective tool for design verification and project management with excellent capabilities for application to new designs and operating plant support. This is accomplished through the CAD plant model and associated data base, which results in reducing human error, more complete preengineering before the start of construction and effective space utilization. Furthermore, the data base accurately represents the as-built plant, which is essential for expediting future plant upgrades. Computer-based modeling is less expensive than the conventional scale modeling and the current technology developments viz. optical scanners, photogrammetry, IGES, and advanced minicomputers will favorably improve the cost-effectiveness.

  9. 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

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

    Microsoft Academic Search

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

    1991-01-01

    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

  11. Studies on the Effects of Gaseous Ions on Plant Growth: II. The construction and operation of an air purification unit for use in studies on the biological effects of gaseous ions

    Microsoft Academic Search

    ALBERT P. KRUEGER; J. C. BECKETT; PAUL C. ANDRIESE; SADAO KOTAKA

    1962-01-01

    Air pollutants seriously interfere with the maintenance ofunipolar 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 satis- factorily in conducting experiments with plants and animals.

  12. Case study of the effects of public safety regulation on the construction costs of coal-fired and nuclear power plants

    SciTech Connect

    Morris, C.D.

    1987-01-01

    Regulations intended to reduce the number of accidents at nuclear plants and the discharge of sulfur and particulate wastes at coal-fired power plants have become an important cause of construction cost escalation. Measuring the costs of these regulatory interventions is a difficult research task. The three-unit Bruce Mansfield coal-fired plant and the two-unit Beaver Valley nuclear power station located in Shippingport, Pennsylvania, provide a unique opportunity for a case study of the costs of regulation in the construction of both kinds of plants. The units of each plant were built sequentially over a period of intensifying regulation. The method used to measure the costs of public safety regulation in the construction of each kind of plant is to determine the connections between the issuances of the regulatory agencies (EPA and NRC) and cost escalations of succeeding units. The small cost escalations of the Mansfield 3 unit, in comparison to the massive costs of the Beaver Valley 2 unit, suggest that the design and construction of new coal-fired plants are not disrupted by regulatory interventions nearly as extensively as are nuclear units. Certain technical features of Beaver Valley 2, especially its small size and a design that is identical to the first unit's, further contribute to its cost escalations.

  13. 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.

  14. 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

  15. Power plant construction is over: What do I do now

    Microsoft Academic Search

    T. B. Thamm; M. Strandell

    1990-01-01

    During the last 20 years, a massive power plant construction program was undertaken in the United States. During the second decade of this construction program, the cost and schedule of many power plants exceeded initial estimates by orders of magnitude. The prudence of utility management came under heavy fire from regulatory bodies, urged on by consumer advocates, pro-environment groups, and

  16. Construction plant breakdown criticality analysis – part 1:UAE perspective

    Microsoft Academic Search

    P. B. Ahamed Mohideen; M. Ramachandran; Rajam Ramasamy Narasimmalu

    2011-01-01

    Purpose – The purpose of this paper to develop a novel strategic approach to handle corrective maintenance procedure in the event of a breakdown\\/disruption of service. A proposal to minimize the recovery time and the breakdown cost in the system in construction plant is presented. Design\\/methodology\\/approach – The past plant breakdown records of a construction organization are considered for the

  17. Constructing and Planting Fast Plants in a Deli-containter Growing System

    NSDL National Science Digital Library

    The Wisconsin Fast Plants Program

    Illustrated instructions for constructing and planting in the Fast Plants deli-container growing system. This is a stable growing system that is easy to construct for all age learners, and works well for growing Wisconsin Fast Plants. Made from recycled deli-containers, these growing systems can be cleaned and reused for multiple years.

  18. 47 CFR 32.2003 - Telecommunications plant under construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2003 Telecommunications plant under construction. (a) This account shall include the original...

  19. 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

  20. 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. 32.2003 Section 32.2003 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER...

  1. Modular construction approach for advanced nuclear plants

    Microsoft Academic Search

    F. T. Johnson; R. S. Orr; C. P. Boudreaux

    1988-01-01

    Modular construction has been designated as one of the major features of the AP600 program, a small innovative 600-MW (electric) advanced light water reactor (ALWR) that is currently being developed by Westinghouse and its subcontractors. This program is sponsored by the US Department of Energy (DOE) in conjunction with several other DOE and Electric Power Research Institute ALWR programs. Two

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

    PubMed

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

    2014-01-01

    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. PMID:24938305

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

    PubMed Central

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

    2014-01-01

    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. PMID:24938305

  4. TECHNICAL ARTICLES PLANTS USED IN CONSTRUCTED WETLANDS AND THEIR

    E-print Network

    Brix, Hans

    TECHNICAL ARTICLES #12;2 PLANTS USED IN CONSTRUCTED WETLANDS AND THEIR FUNCTIONS Hans Brix Risskov, Denmark ABSTRACT Vegetation plays an important role in wastewater treatment wetlands. Plants treatment systems aesthetically pleasing. Wetland species of all growth forms have been used in treatment

  5. Toshiba's developments on construction techniques of nuclear power plants

    Microsoft Academic Search

    Y. Hayashi; N. Itoh

    1987-01-01

    Reliable and economic energy supplies are fundamental requirements of energy policies in Japan. To accomplish these needs, nuclear power plants are being increased in Japan. In recent years, construction cost increases and schedule extensions have affected the capital cost of nuclear energy, compared with fossil power plants, due to lower costs of oil and coal. On the other hand, several

  6. 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

  7. 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

  8. 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.

  9. Effect of loading rate and planting on treatment of dairy farm wastewaters in constructed wetlands—I. Removal of oxygen demand, suspended solids and faecal coliforms

    Microsoft Academic Search

    Chris C. Tanner; John S. Clayton; Martin P. Upsdell

    1995-01-01

    The effect of influent loading rate on mass removal of BOD, SS and faecal coliforms (FC) from dairy parlour wastewaters was compared in four pairs of planted (Schoenoplectus validus) and unplanted gravel-bed wetlands (each 19 m2). The wetlands were operated at nominal retention times of 7, 5.5, 3 and 2 days, with in and outflows sampled fortnightly over a 20

  10. Effect of loading rate and planting on treatment of dairy farm wastewaters in constructed wetlands—II. Removal of nitrogen and phosphorus

    Microsoft Academic Search

    Chris C. Tanner; John S. Clayton; Martin P. Upsdell

    1995-01-01

    The effect of influent loading rate on mass removal of nitrogen and phosphorus from dairy parlour wastewaters was compared in four pairs of planted (Schoenoplectus validus) and unplanted gravel-bed wetlands (each 19 m2). The wetlands were operated at nominal retention times of 7, 5.5, 3 and 2 days, with in and outflows sampled fortnightly over a 20 month period. Hydraulic

  11. H-02 CONSTRUCTED WETLAND STUDIES AMPHIBIANS AND PLANTS

    E-print Network

    Georgia, University of

    H-02 CONSTRUCTED WETLAND STUDIES AMPHIBIANS AND PLANTS FY-2009 ANNUAL REPORT Savannah River Ecology ................................................................................................. 4 Chapter II Amphibian and Reptile Use of the H-02 Wetland .................................... 5 ............................................................................................... 27 Chapter III Vegetation Community of the H-02 Wetlands: Importance to Amphibians

  12. H-02 CONSTRUCTED WETLAND STUDIES AMPHIBIANS AND PLANTS

    E-print Network

    Georgia, University of

    H-02 CONSTRUCTED WETLAND STUDIES AMPHIBIANS AND PLANTS FY-2008 ANNUAL REPORT Savannah River Ecology ................................................................................................. 4 CHAPTER II -- AMPHIBIAN AND REPTILE USE OF THE H-02 WETLAND .................................... 5 ............................................................................................... 17 CHAPTER III: VEGETATION COMMUNITY OF THE H-02 WETLANDS -- IMPORTANCE TO AMPHIBIANS

  13. Construction plant and equipment management research: thematic review

    Microsoft Academic Search

    David J. Edwards; Gary D. Holt

    2009-01-01

    Purpose – A literature review is presented in the subject of construction plant and equipment management (CPeM) to: delineate the subject; consider its development over recent years; and identify principal themes within it. The paper aims to close the gap in knowledge, by using these objectives as a mechanism to observe how research themes relate to primary CPeM functions, and

  14. Construction labor assessment for coal gasification plant Murphy Hill, Alabama

    SciTech Connect

    Not Available

    1980-11-01

    TVA's planned construction of a coal gasification plant, capable of processing about 20,000 tons of coal per day into a clean-burning fuel, will be a large and complex construction project by any relevant measure. The plant site examined here is in northern Alabama near Murphy Hill. The project is estimated to require nearly 7000 workers at peak employment in 1985. It is projected that construction will start in early 1981 and be completed in 1988. Nearly 66 percent of all construction craft worker requirements are expected to occur during a 36-month period from 1984 to 1986, and about 25 percent are projected to occur during the 1985 calendar year alone. This construction labor market assessment report is directed toward establishing and analyzing data on construction labor requirements, and labor availability for the 75-mile geographical zone surrounding Murphy Hill, Alabama. The purpose of this report is to examine potential skilled labor shortages and some alternatives for alleviating those shortages, but not to address the array of socioeconomic implications of reducing shortages by training, by attracting workers who move permanently to the job site, or by attracting workers who live temporarily near the site and return home periodically. Parameters and assessments of the Murphy Hill construction labor market have been developed for: the 75-mile geographical zone surrounding the site; the major skilled construction trades involved; the time phase of construction labor demand; and projected craft-specific labor shortfalls. These objectives have been developed within the engineering bounds of the TVA's labor planning memo.

  15. Signalling Network Construction for Modelling Plant Defence Response

    PubMed Central

    Miljkovic, Dragana; Stare, Tjaša; Mozeti?, Igor; Podpe?an, Vid; Petek, Marko; Witek, Kamil; Dermastia, Marina; Lavra?, Nada; Gruden, Kristina

    2012-01-01

    Plant defence signalling response against various pathogens, including viruses, is a complex phenomenon. In resistant interaction a plant cell perceives the pathogen signal, transduces it within the cell and performs a reprogramming of the cell metabolism leading to the pathogen replication arrest. This work focuses on signalling pathways crucial for the plant defence response, i.e., the salicylic acid, jasmonic acid and ethylene signal transduction pathways, in the Arabidopsis thaliana model plant. The initial signalling network topology was constructed manually by defining the representation formalism, encoding the information from public databases and literature, and composing a pathway diagram. The manually constructed network structure consists of 175 components and 387 reactions. In order to complement the network topology with possibly missing relations, a new approach to automated information extraction from biological literature was developed. This approach, named Bio3graph, allows for automated extraction of biological relations from the literature, resulting in a set of (component1, reaction, component2) triplets and composing a graph structure which can be visualised, compared to the manually constructed topology and examined by the experts. Using a plant defence response vocabulary of components and reaction types, Bio3graph was applied to a set of 9,586 relevant full text articles, resulting in 137 newly detected reactions between the components. Finally, the manually constructed topology and the new reactions were merged to form a network structure consisting of 175 components and 524 reactions. The resulting pathway diagram of plant defence signalling represents a valuable source for further computational modelling and interpretation of omics data. The developed Bio3graph approach, implemented as an executable language processing and graph visualisation workflow, is publically available at http://ropot.ijs.si/bio3graph/and can be utilised for modelling other biological systems, given that an adequate vocabulary is provided. PMID:23272172

  16. 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.

  17. Upgrading Water Treatment Plants: An Alternative to New Construction

    Microsoft Academic Search

    Robert E. Forbes; Gary L. Nickerson; Herbert E. Hudson Jr.; Edmund G. Wagner

    1980-01-01

    Because of more stringent water quality requirements, many water utilities must reevaluate the operation of plant facilities to determine that optimum water quality is being provided in the most efficient and cost effective manner. Modifying unit processes of surface water filtration plants such as rapid mixing, flocculation, sedimentation, filtration, and process control can improve finished water quality, reduce operating costs,

  18. Designing and constructing the Trap Falls water treatment plant

    Microsoft Academic Search

    Mark L. Johnson; Peter W. Doe

    1983-01-01

    The challenge of designing and building a 94-ML\\/d (25-mgd) water treatment plant to meet new water quality standards was successfully accomplished by the Bridgeport (Conn.) Hydraulic Company. A constricted site located near a highway and several dwellings called for an aesthetic architectural solution as well as the use of unusual water treatment technology. A fast-track design and construction program achieved

  19. 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.

  20. 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

  1. 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

  2. 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

  3. Plant growth and microbial processes in a constructed wetland planted with Phalaris arundinacea

    Microsoft Academic Search

    Keith R. Edwards; Hana ?ižková; Kate?ina Zemanová; Hana Šantr??ková

    2006-01-01

    We report on the first year results from a project studying plant growth, nutrient cycling and microbial processes in a 5-year-old constructed wetland in South Bohemia, Czech Republic. The goal of the study was to estimate nutrient fluxes and determine the roles of plants (Phalaris arundinacea L.) and microbial processes in decreasing nutrient pollution. Pore water nutrient concentrations (NO3, NH4

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

    SciTech Connect

    Kenji Akagi; Masayuki Ishiwata; Kenji Araki; Jun-ichi Kawahata [Hitachi, Ltd. (Japan)

    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)

  5. 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. [and others

    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.

  6. 21 CFR 111.20 - What design and construction requirements apply to your physical plant?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...construction requirements apply to your physical plant? 111.20 Section 111.20 Food...OPERATIONS FOR DIETARY SUPPLEMENTS Physical Plant and Grounds § 111.20 What design...construction requirements apply to your physical plant? Any physical plant you use in...

  7. 21 CFR 111.20 - What design and construction requirements apply to your physical plant?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...construction requirements apply to your physical plant? 111.20 Section 111.20 Food...OPERATIONS FOR DIETARY SUPPLEMENTS Physical Plant and Grounds § 111.20 What design...construction requirements apply to your physical plant? Any physical plant you use in...

  8. 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

    2014-08-01

    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 O?/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 NH?-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. PMID:24777322

  9. 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…

  10. Arrival order among native plant functional groups does not affect invasibility of constructed dune communities.

    PubMed

    Mason, T J; French, K; Jolley, D

    2013-10-01

    Different arrival order scenarios of native functional groups to a site may influence both resource use during development and final community structure. Arrival order may then indirectly influence community resistance to invasion. We present a mesocosm experiment of constructed coastal dune communities that monitored biotic and abiotic responses to different arrival orders of native functional groups. Constructed communities were compared with unplanted mesocosms. We then simulated a single invasion event by bitou (Chrysanthemoides monilifera ssp. rotundata), a dominant exotic shrub of coastal communities. We evaluated the hypothesis that plantings with simultaneous representation of grass, herb and shrub functional groups at the beginning of the experiment would more completely sequester resources and limit invasion than staggered plantings. Staggered plantings in turn would offer greater resource use and invasion resistance than unplanted mesocosms. Contrary to our expectations, there were few effects of arrival order on abiotic variables for the duration of the experiment and arrival order was unimportant in final community invasibility. All planted mesocosms supported significantly more invader germinants and significantly less invader abundance than unplanted mesocosms. Native functional group plantings may have a nurse effect during the invader germination and establishment phase and a competitive function during the invader juvenile and adult phase. Arrival order per se did not affect resource use and community invasibility in our mesocosm experiment. While grass, herb and shrub functional group plantings will not prevent invasion success in restored communities, they may limit final invader biomass. PMID:23468238

  11. 75 FR 59933 - Specifications and Drawings for Construction of Direct Buried Plant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-29

    ...Service 7 CFR Part 1755 Specifications and Drawings for Construction of Direct Buried Plant...Bulletin 1753F-150, Specifications and Drawings for Construction of Direct Buried Plant...Bulletin 1753F-150, Specifications and Drawings for Construction of Direct Buried...

  12. 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...

  13. DESIGN MANUAL: CONSTRUCTED WETLANDS AND AQUATIC PLANT SYSTEMS FOR MUNICIPAL WASTEWATER TREATMENT

    EPA Science Inventory

    This publication is a compilation of all available design and operating criteria for the various constructed wetlands and aquatic plant systems. opics discussed include: aquatic treatment systems, environmental and health considerations, design of constructed wetlands, design of ...

  14. 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. PMID:19036399

  15. 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

  16. 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

  17. [Ecological risk assessment of dam construction for terrestrial plant species in middle reach of Lancangjiang River, Southwest China].

    PubMed

    Li, Xiao-Yan; Dong, Shi-Kui; Liu, Shi-Liang; Peng, Ming-Chun; Li, Jin-Peng; Zhao, Qing-He; Zhang, Zhao-Ling

    2012-08-01

    Taking the surrounding areas of Xiaowan Reservoir in the middle reach of Lancangjiang River as study area, and based on the vegetation investigation at three sites including electricity transmission area (site 1), electricity-transfer substation and roadsides to the substation (site 2), and emigration area (site 3) in 1997 (before dam construction), another investigation was conducted on the vegetation composition, plant coverage, and dominant species at the same sites in 2010 (after dam construction), aimed to evaluate the ecological risk of the dam construction for the terrestrial plant species in middle reach of Lancangjiang River. There was an obvious difference in the summed dominance ratio of dominant species at the three sites before and after the dam construction. According the types of species (dominant and non-dominant species) and the changes of plant dominance, the ecological risk (ER) for the plant species was categorized into 0 to IV, i.e., no or extremely low ecological risk (0), low ecological risk (I), medium ecological risk (II), high ecological risk (III), and extremely high ecological risk (IV). As affected by the dam construction, the majority of the species were at ER III, and a few species were at ER IV. The percentage of the plant species at ER III and ER IV at site 3 was higher than that at sites 1 and 2. The decrease or loss of native plants and the increase of alien or invasive plants were the major ecological risks caused by the dam construction. Effective protection strategies should be adopted to mitigate the ecological risk of the dam construction for the terrestrial plants at species level. PMID:23189705

  18. Risk Framework for the Next Generation Nuclear Power Plant Construction

    E-print Network

    Yeon, Jaeheum 1981-

    2012-12-11

    Uncertainty can be either an opportunity or a risk. Every construction project begins with the expectation of project performance. To meet the expectation, construction projects need to be managed through sound risk assessment and management...

  19. Innovation or business survival? : A preliminary, qualitative study of UK construction plant supply chains

    Microsoft Academic Search

    Gary D. Holt; David J. Edwards

    2012-01-01

    Purpose – The criticality of mechanical plant to construction activity is well accepted within the literature; however, the supply chain mechanisms by which that demand is satisfied, are much less documented or understood. The purpose of this paper is to address this theoretical gap by: describing Construction Plant Supply Chain (CPSC) evolvement; identifying with present sector difficulties; discussing solutions to

  20. The effects of psammophilous plants on sand dune dynamics

    E-print Network

    Bel, Golan

    2013-01-01

    Psammophilous plants are special plants that flourish in sand moving environments. There are two main mechanisms by which the wind affects these plants: (i) sand drift exposes roots and covers branches--the exposed roots turn into new plants and the covered branches turn into new roots; both mechanisms result in an enhanced growth rate of the psammophilous plant cover of the dunes; (ii) strong winds, often associated with sand movement, tear branches and seed them in nearby locations, resulting in new plants and an enhanced growth rate of the psammophilous plant cover of the dunes. Despite their important role in dune dynamics, to our knowledge, psammophilous plants have never been incorporated into mathematical models of sand dunes. Here, we attempt to model the effects of these plants on sand dune dynamics. We construct a set of three ordinary differential equations for the fractions of surface cover of regular vegetation, biogenic soil crust and psammophilous plants. The latter reach their optimal growth u...

  1. Hydrogen production by high temperature, high pressure water electrolysis. III - Design and construction of test plant

    Microsoft Academic Search

    Y. Kajiwara; S. Maezawa; K. Matsunaga

    1981-01-01

    The design and construction of a test plant of hydrogen capacity 4 cu Nm\\/hour based on high-temperature, high-pressure water electrolysis which was built to obtain technical data for the construction of a 20-cu Nm\\/hour pilot plant are outlined. The test plant is a forced circulation system comprised of an electrolyzer, electrolyte circulation line, gas-liquid separator, hydrogen\\/oxygen production gas line, measurement

  2. Prospects of two-contour geothermal power plant construction

    Microsoft Academic Search

    A. B. Alkhasov; R. M. Aliyev; Kh. G. Magomedbekov

    1997-01-01

    Technologycal scheme of electric energy obtaining on the basis of thermal water is suggested. The method of optimal regime calculation is presented. Some parametries of Daghestan Geothermal power plant are presented.

  3. Effect of plant fill ratio on water temperature in constructed wetlands 1 This work was supported by the Alabama Agricultural Experiment Station (AAES) under Regional Research Project S-275 and by the USDA-NRCS under Cooperative Agreement No. 68-4104-2-18. It is designated as Journal Series No. 2-985925 by the AAES. 1

    Microsoft Academic Search

    D. T Hill; J. D Payton

    2000-01-01

    An existing free-water-surface constructed wetland system at the Auburn University Poultry Science Unit was used to evaluate the effect of plant fill ratio on water temperature. Each wetland consisted of two cells in series. One series was operated with an approximate 10% fill of Sagittaria lancifolia (duck-potato). A second series contained Phragmites australis (common reed) and Scirpus spp. (bulrush) with

  4. 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 community. During the recovery period, the plant community in the work area of the pipeline is replaced by some species that are rare or uncommon in the resident plant community because of human disturbance, thereby increasing the plant diversity in the work area. In terms of plant succession, the duration of the recovery period has a direct effect on the composition and structure of the plant community. The findings provide a theoretical basis and scientific foundation for improving the environmental impact assessment (EIA) of oil and gas pipeline construction as it pertains to the desert steppe ecosystem, and provide a reference point for recovery and management of the eco-environment during the pipeline construction period. PMID:25112841

  5. 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

  6. 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.

  7. Establishing native plants on newly-constructed and older-reclaimed sites along West Virginia highways

    Microsoft Academic Search

    J. G. Skousen; C. L. VENABLEz

    2008-01-01

    Manystate highway departments in the USA must use native plants forrevegetating roadsides. We conducted twofieldstudies in West Virginia to assess native plant establishment under two different conditions. On newly-constructed sites, native species were seeded alone or combined with non-native species. On older roadsides, native species were seeded in disturbed existing vegetation. In the first study, we used four seed mixtures

  8. Plant photosynthesis and its influence on removal efficiencies in constructed wetlands

    Microsoft Academic Search

    Juan Huang; Shi-he Wang; Lu Yan; Qiu-shuang Zhong

    2010-01-01

    The photosynthetic characteristics of several wetland plants and their influence on oxygen-evolving activities and disposal efficiencies of horizontal flow subsurface constructed wetlands were compared. The results indicated that the photosynthetic rate of wetlands plants was highly correlated with light intensity and temperature. The photosynthetic characteristics of wetlands species can affect their ability to provide oxygen, and this ultimately influences their

  9. Boom & Bust in Power Plant Construction: Lessons from the California Electricity Crisis

    E-print Network

    Ford, Andrew

    1 Boom & Bust in Power Plant Construction: Lessons from the California Electricity Crisis To Appear throughout the west, and continued into the winter and spring of 2001. Then, to the surprise of many, chronic in the previous year, and natural gas prices fell dramatically. New power plants came on line, and many more

  10. 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 [Burlington Northern Santa Fe Railway Co. (United States)

    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.

  11. 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,…

  12. 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.

  13. Plant litter: Its dynamics and effects on plant community structure

    Microsoft Academic Search

    José M. Facelli; Steward T. A. Pickett

    1991-01-01

    We discuss the dynamics of plant litter, the effects of litter on the chemical and physical environment, the direct and indirect\\u000a effects of plant litter on plant populations and communities, and different adaptative traits that may be related to litter\\u000a accumulation. The production of litter depends primarily on the site productivity, but other properties of the environment,\\u000a as well as

  14. Climate Change Effects on Plant Disease: Genomes

    E-print Network

    Garrett, Karen A.

    Climate Change Effects on Plant Disease: Genomes to Ecosystems K. A. Garrett, S. P. Dendy, E. E in the effects of climate change on plant disease contin- ues to be limited, but some striking progress has been of the magnitude of climate change effects. Ecosystem ecologists are now addressing the role of plant disease

  15. 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

  16. 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.

  17. 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. PMID:23508157

  18. Causes and effects of delays in Malaysian construction industry

    Microsoft Academic Search

    Murali Sambasivan; Yau Wen Soon

    2007-01-01

    The problem of delays in the construction industry is a global phenomenon and the construction industry in Malaysia is no exception. The main purpose of this study is to identify the delay factors and their impact (effect) on project completion. Earlier studies either considered the causes or the effects of project delays, separately. This study takes an integrated approach and

  19. 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. PMID:22664683

  20. Modeling of fugitive dust emission for construction sand and gravel processing plant.

    PubMed

    Lee, C H; Tang, L W; Chang, C T

    2001-05-15

    Due to rapid economic development in Taiwan, a large quantity of construction sand and gravel is needed to support domestic civil construction projects. However, a construction sand and gravel processing plant is often a major source of air pollution, due to its associated fugitive dust emission. To predict the amount of fugitive dust emitted from this kind of processing plant, a semiempirical model was developed in this study. This model was developed on the basis of the actual dust emission data (i.e., total suspended particulate, TSP) and four on-site operating parameters (i.e., wind speed (u), soil moisture (M), soil silt content (s), and number (N) of trucks) measured at a construction sand and gravel processing plant. On the basis of the on-site measured data and an SAS nonlinear regression program, the expression of this model is E = 0.011.u2.653.M-1.875.s0.060.N0.896, where E is the amount (kg/ton) of dust emitted during the production of each ton of gravel and sand. This model can serve as a facile tool for predicting the fugitive dust emission from a construction sand and gravel processing plant. PMID:11393989

  1. Nuclear power plant construction: What can be learned from past and on-going projects?

    Microsoft Academic Search

    Benoît Zerger; Marc Noël

    This paper presents a study performed by the European Clearinghouse on Operational Experience for NPPs and covering events related to construction, commissioning and manufacturing of nuclear power plants (i.e. events prior to the start of commercial operation). The events considered are both issues detected during the pre-operational stages, and events detected during further operation of the plant.This study summarises the

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

    SciTech Connect

    Jackson, R.P. Jr. [Army Environmental Center, Aberdeen Proving Ground, MD (United States)

    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.

  3. Construction of genetic linkage map of the medicinal and ornamental plant Catharanthus roseus

    Microsoft Academic Search

    Sarika Gupta; Sashi Pandey-Rai; Suchi Srivastava; Subhas Chandra Naithani; Manoj Prasad; Sushil Kumar

    2007-01-01

    An integrated genetic linkage map of the medicinal and ornamental plant Catharanthus roseus, based on different types of molecular and morphological markers was constructed, using a F2 population of 144 plants. The map defines 14 linkage groups (LGs) and consists of 131 marker loci, including 125 molecular\\u000a DNA markers (76 RAPD, 3 RAPD combinations; 7 ISSR; 2 EST-SSR from Medicago

  4. Effectiveness of 4D construction modeling in detecting time-space conflicts of construction sites

    E-print Network

    Nigudkar, Narendra Shriniwas

    2005-11-01

    , communication, and coordination, for the construction of the Walt Disney Concert Hall in Los Angeles, designed by Frank O. Gehry. (Hastings et al. 2003). In another research to study the effect of 4D model on construction planning, Common Point 4D Inc.?s CPT4... Company and Mr. John Robertson of RWS Architects for allowing me to conduct this research on their construction project. I am thankful to my family and friends from whom I received strong support and encouragement. I am deeply indebted to my...

  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. 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

  7. 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)

  8. Ways of optimization of pumped-storage plant dike design based on modern construction methods

    Microsoft Academic Search

    S. V. Bortkevich

    1992-01-01

    Design and construction of pumped-storage plants using new technical solutions which raise the operating quality of the structures and lower their cost have been the object of considerable attention on the part of the journal Gidrotekhnicheskoe Stroitel'stvo. Previously, in the sections \\

  9. Modeling the Constructs Contributing to the Effectiveness of Marketing Lecturers

    ERIC Educational Resources Information Center

    Sweeney, Arthur D. P.; Morrison, Mark D.; Jarratt, Denise; Heffernan, Troy

    2009-01-01

    Student evaluation of teaching has been examined in higher education research for over 70 years but there are gaps in our knowledge about the contribution, and relationships between, the relevant constructs. Recent literature encourages researchers to test multivariate models of Teaching Effectiveness. Seven main constructs known to influence…

  10. Effects of herbivores on grassland plant diversity

    Microsoft Academic Search

    Han Olff; Mark E. Ritchie

    1998-01-01

    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

  11. 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.

  12. 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).

  13. Planning a Program of School Plant Construction. Research Report, School Plant Planning Series.

    ERIC Educational Resources Information Center

    Utah State Board of Education, Salt Lake City.

    The importance of long-term planning, and undesirable conditions resulting from failure to plan, are stressed. General procedures named as essential are--(1) the official approval of the Board of Education before the administration proceeds with long-range planning, (2) the design of the school plant around the educational program it is to serve,…

  14. Improving quality and the assurance of quality in the design and construction of nuclear power plants: a report to Congress

    Microsoft Academic Search

    W. Altman; T. Ankrum; W. Brach

    1984-01-01

    A study was conducted of existing and alternative programs for improving quality and the assurance of quality in the design and construction of commercial nuclear power plants. A primary focus of the study was to determine the underlying causes of major quality-related problems in the construction of some nuclear power plants and the untimely detection and correction of these problems.

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

    SciTech Connect

    NONE

    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.

  16. The effects of psammophilous plants on sand dune dynamics

    E-print Network

    Golan Bel; Yosef Ashkenazy

    2013-08-30

    Psammophilous plants are special plants that flourish in sand moving environments. There are two main mechanisms by which the wind affects these plants: (i) sand drift exposes roots and covers branches--the exposed roots turn into new plants and the covered branches turn into new roots; both mechanisms result in an enhanced growth rate of the psammophilous plant cover of the dunes; (ii) strong winds, often associated with sand movement, tear branches and seed them in nearby locations, resulting in new plants and an enhanced growth rate of the psammophilous plant cover of the dunes. Despite their important role in dune dynamics, to our knowledge, psammophilous plants have never been incorporated into mathematical models of sand dunes. Here, we attempt to model the effects of these plants on sand dune dynamics. We construct a set of three ordinary differential equations for the fractions of surface cover of regular vegetation, biogenic soil crust and psammophilous plants. The latter reach their optimal growth under (i) specific sand drift or (ii) specific wind power. We show that psammophilous plants enrich the sand dune dynamics. Depending on the climatological conditions, it is possible to obtain one, two, or three steady dune states. The activity of the dunes can be associated with the surface cover--bare dunes are active, and dunes with significant cover of vegetation, biogenic soil crust, or psammophilous plants are fixed. Our model shows that under suitable precipitation rates and wind power, the dynamics of the different cover types is in accordance with the common view that dunes are initially stabilized by psammophilous plants that reduce sand activity, thus enhancing the growth of regular vegetation that eventually dominates the cover of the dunes and determines their activity.

  17. Tracer studies and hydraulic behaviour of planted and un-planted vertical-flow constructed wetlands.

    PubMed

    Cota, R S; von Sperling, M; Penido, R C S

    2011-01-01

    The aim of this research was to assess the hydraulic behaviour of three intermittently-fed vertical flow wetland units operated in parallel, designed for the treatment of raw wastewater generated in the city of Belo Horizonte, Brazil. The system was designed to serve 100 PE (-1 m2/PE). The first filter was planted with cattail (Typha latifolia), the second with Tifton-85 (Cynodon spp.) and the third was maintained without plants (control unit). NaCl tracer tests were conducted to determine the residence time distribution. The tests were done with water when the system was unused (clean media) and also after an 11-month operation period with wastewater (used media), using two different dosing regimes (lower and higher frequency). Results showed a strong tendency towards the hydraulic completely mixed regime. A great dispersion in the units and the presence of short circuiting and dead zones were observed. The unsaturated condition in a large volume of the filter, even during the draining stage, was confirmed for the three units. The dosing regime, the resting period duration, the age of the filter and the presence of plants were found to influence the hydraulic processes in the units. PMID:22214051

  18. Air pollution effects on plant growth

    Microsoft Academic Search

    1974-01-01

    The volume discusses new avenues of research from those who represent the second and third generations of scientists working in the field of oxidant air pollution effects. Eleven papers discuss topics which include: plant-environment interaction, effects of ozone on cell permeability, reaction of ozone with lysozyme, alterations of metabolite pools, ozone injury to cell membranes, pigmentation and physiology of plant

  19. Plant operator simulation: benefits and drawbacks for a construction training organization

    Microsoft Academic Search

    Jennifer Tichon; Phil Diver

    2010-01-01

    The civil construction industry in Australia is under pressure to attract, train and retain high numbers of skilled personnel.\\u000a At the same time it is recognized as one of the most dangerous industries in the country. To counteract the safety issues\\u000a and the labor shortages, plant operator training augmented by simulation is being investigated as an alternative to current\\u000a training

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

    Microsoft Academic Search

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

    2007-01-01

    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%.

  1. Solar energy storage by salinity gradient solar pond: Pilot plant construction and gradient control

    Microsoft Academic Search

    César Valderrama; Oriol Gibert; Jordina Arcal; Pau Solano; Aliakbar Akbarzadeh; Enric Larrotcha; José Luis Cortina

    2011-01-01

    An experimental solar pond pilot plant was constructed in Solvay-Martorell, facilities, Catalonia (NE part of the Iberian Peninsula) to capture and store solar energy. The body of the pond is a cylindrical reinforced concrete tank, 3m height, 8m diameter and total area of 50m2. Salinity and thermal gradient were properly established by using the salinity distribution methodology. The gradient in

  2. Heber geothermal binary demonstration plant: Design, construction, and early startup: Topical report

    SciTech Connect

    Riley, J. R.

    1987-10-01

    Study of the concept for a large commercial size binary-cycle geothermal demonstration plant began in 1974. It was perceived that such a project would fill the need to advance the art of binary-cycle technology to the point that it could be used on a large scale for the development of moderate temperature geothermal resources. The Plant is rated at 45 MWe (net) and is located near Heber in the Imperial Valley of California. Construction began in June 1983 and as completed in June 1985. This report presents the results of design studies and field experiments that provided the data for detailed design. It discusses the plant's final design, highlights the logic behind key design decisions, and gives project costs. It describes the planned three-year test and demonstration program. It also includes a list of reports, studies, project documents, and technical papers related to the project.

  3. 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 wetland to remediate high levels of perchlorate polluted water. PMID:23673920

  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. PMID:19303772

  5. Effect of Environment on Plant Growth

    NSDL National Science Digital Library

    Janice Stephens

    2011-01-01

    The purpose of this plant biotechnology activity is to demonstrate the effect of changes in the environment on the growth and fertility of landscape grasses and crop grasses such as wheat and rice. Plants are placed in environments such as high salinity, cold, heat, or drought and learners observe the different reactions of the plants to these conditions. Learners compare the growth of treated plants to that of the control plants, which are grown under optimal conditions. Learners then discuss the desirability of breeding new types of plants that are better able to withstand these changes if they occur in the general environment. In the original description of the activity, the planting is prepared by the instructor as a demonstration, but learners could be involved in this process. This resource contains background information and questions for learners.

  6. 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. PMID:19955625

  7. 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).

  8. [Excitation-emission matrix fluorescence spectra characteristics of DOM in a subsurface constructed wetland for advanced treatment of municipal sewage plant effluent].

    PubMed

    Yang, Chang-ming; Wang, Meng-meng; Ma, Rui; Li, Jian-hua

    2012-03-01

    Composition and dynamics of dissolved organic matter (DOM) were analyzed in a horizontal subsurface constructed wetland for advanced treatment of municipal sewage plant effluent using three-dimensional excitation emission matrix fluores cence spectroscopy (3D-EEM). The results indicate that the two subsurface constructed wetlands performed excellent purification of organic substances, and the removal rates of COD(cr), and DOC were 61.6% and 70.1%, respectively. The constructed wetland system filled with ceramsite showed slightly greater removal efficiency of organic substance than that with zeolite substrate. Four different types of peaks such as aromatic protein-like compounds (S), soluble microbial byproducts (T), fulvic acid-like compounds, visible fulvic-like (M) and UV fulvic-like compounds (A) were found in DOM from inflow and outflow of the subsurface wetlands based on the three-dimensional fluorescence spectroscopy analysis. The fluorescence intensity of the four peaks was significantly decreased in the effluent after purification by the subsurface constructed wetlands. Especially, the visible fulvic-like compounds and soluble microbial byproducts were effectively removed from the sewage plant effluent by the subsurface constructed wetland with fluorescence intensity reduction percentages of 16.4% and 11.7%. Aromatic structures of humic-like compounds were weakened and organic compounds with benzene rings were decreased in the outflow of the subsurface constructed wetland. This indicates that the subsurface constructed wetlands can decompose the chemically stable and biorefractory humic-like compounds. The fluorescence intensity of M and T peaks decreased along distance, while the fluorescence intensity of S peaks firstly increased, then decreased along the distance of the subsurface constructed wetlands. As compared to zeolite substrate constructed wetland system, the constructed wetland system filled with ceramsite was more effective to reduce the fluorescence intensity of characterized peaks of DOM from the sewage plant effluent. PMID:22582638

  9. Effects of managed impoundments and herbivory on wetland plant production and stand structure

    Microsoft Academic Search

    Lori A. Johnson Randall; A. Lee Foote

    2005-01-01

    Managed impoundments, a form of structural marsh management, have been used to enhance plant production in the rapidly-eroding\\u000a marshes of coastal Louisiana, USA, yet few studies have quantified their effects by measuring plant production before and\\u000a after impoundment construction. We tested the effects of structural marsh management on the annual aboveground production\\u000a and plant stand structure (stem density and stem

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

    PubMed

    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

  11. 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.

  12. 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…

  13. RADON MITIGATION EFFECTS OF PASSIVE STACKS IN RESIDENTIAL NEW CONSTRUCTION

    EPA Science Inventory

    The paper discusses the effects of passive stacks in mitigating radon levels in residential new construction. Although passive stacks have been installed as a radon resistant measure in new houses, little quantitative data on their performance has been collected. This study invol...

  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. A comparative study of five horizontal subsurface flow constructed wetlands using different plant species for domestic wastewater treatment.

    PubMed

    Villaseñor Camacho, J; De Lucas Martínez, A; Gómez Gómez, R; Mena Sanz, J

    2007-12-01

    This project studied domestic wastewater treatment by horizontal subsurface flow (HSSF) constructed wetlands (CW) and compared the effect of four different plant species on the operating conditions, dissolved oxygen (DO), and redox potential (ORP), and their efficiency on pollutants removal. Five HSSF CWs were fed for 10 months with low loaded synthetic domestic wastewater, using theoretical hydraulic residence time of 7.6 days. The plant species under study were the following: Phragmites australis (CW1), Lythrum salicaria (CW3), Cladium mariscus (CW4) and Iris pseudacorus (CW5). CW2 was not planted and this was used as control. Qualitative measurements determined a greater growth of Lythrum salicaria and Iris pseudacorus than the others. Dissolved oxygen concentrations were very low in the entire bulk liquid of all the CWs. Also ORP values were very similar in all wetlands, dealing with facultative anaerobic environments. All planted wetlands improved pollutants removal compared with the unplanted control wetland. The performances in terms of COD, TN, TP and SO4(2-) removal obtained by the different CWs were in the ranges 80-90%, 35-55%, 15-40% and 45-60% respectively. Lythrum salicaria and Iris pseudacorus, which exhibited greater growth, were always the most efficient species that improved not only nutrients plant uptake but also other microbial removal processes probably due to a higher aeration potential, such as nitrification or aerobic respiration. Sulphate reduction was the most important mechanism for COD removal. Cladium mariscus, an autochthonous plant that grows in the south-central Iberian Peninsula, was less efficient than Lythrum salicaria and Iris pseudacorus, but improved the unplanted wetland wastewater efficiency. PMID:18341144

  16. Effects of cobalt on plants

    Microsoft Academic Search

    Syamasri Palit; Archana Sharma; Geeta Talukder

    1994-01-01

    Cobalt, a transition element, is an essential component of several enzymes and co-enzymes. It has been shown to affect growth\\u000a and metabolism of plants, in different degrees, depending on the concentration and status of cobalt in rhizosphere and soil.\\u000a Cobalt interacts with other elements to form complexes. The cytotoxic and phytotoxic activities of cobalt and its compounds\\u000a depend on the

  17. 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. PMID:24564587

  18. THE USE OF CONSTRUCTED WETLANDS TO PHYTOREMEDIATE EXPLOSIVES-CONTAMINATED GROUNDWATER AT THE MILAN ARMY AMMUNITION PLANT, MILAN, TENNESSEE

    EPA Science Inventory

    The groundwaters beneath many Army ammunition plants in the United States are contaminated with explosives. To help address this problem, the USAEC and TVA initiated a field demonstration program to evaluate the technical feasibility of using constructed wetlands for remediating ...

  19. 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

    ...2011-01-01 false Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC...

  20. 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

    ...2010-01-01 false Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC...

  1. 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

    ...2013-01-01 false Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC...

  2. 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

    ...2011-01-01 false Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 52 Energy NUCLEAR REGULATORY COMMISSION...

  3. 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

    ...2014-01-01 false Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 52 Energy NUCLEAR REGULATORY COMMISSION...

  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

    ...2010-01-01 false Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 52 Energy NUCLEAR REGULATORY COMMISSION...

  5. 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

    ...2014-01-01 false Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC...

  6. 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

    ...2013-01-01 false Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 52 Energy NUCLEAR REGULATORY COMMISSION...

  7. 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

    ...2012-01-01 false Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 52 Energy NUCLEAR REGULATORY COMMISSION...

  8. 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

    ...2012-01-01 false Standardization of Nuclear Power Plant Designs: Permits To Construct and Licenses To Operate Nuclear Power Reactors of Identical Design at...N Appendix N to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC...

  9. Biochemical effects of air pollution on plants

    Microsoft Academic Search

    D. C. McCune; L. H. Weinstein; J. S. Jacobson; A. De Hertogh; A. E. Hitchcock

    1965-01-01

    The subject of air pollution and its effects on plants is reviewed in depth. Fluoride serves as a basis for generalizations concerning the effects of air pollutants and as an illustration of the evidence that supports them. The biochemical effects of an air pollutant involve many processes that occur at different times and on different levels of organization. The experimental

  10. EFFECTS OF AIR POLLUTANTS ON PLANT PRODUCTIVITY

    EPA Science Inventory

    Air pollutants modify the productivity of agrisystems. Any effect of air pollution on growth or quality of a plant is an effect of productivity. Early efforts to estimate the effects of air pollutants on crop productivity were often based only on observation. Of the different met...

  11. Appraisal of plant diversity effect of the rebuilding and extension project of National Highway 209 Duchuan to Chunshu section

    NASA Astrophysics Data System (ADS)

    Shi, Youhui; Zhang, Qipeng; Li, Haiyan; Dai, Yan

    2011-02-01

    Plant diversity evaluation of highway construction of nature reserve is one important task in a construction project. I analyze and appraisal the plant diversity problems caused by the rebuilding and extension project of No.209 national highway Duchuan to Chunshuya section from plant species diversity, plant composition characteristics, vegetation type's diversity and national rare and endangered plants in the construction region. The highway reconstruction through the Savage Valley Nature Reserve basically causes no destructive effects on plant diversity, but there are still some negative effects. In this paper, I put forward scientific, reasonable and feasible measures and methods to the plant diversity protection by combining with the natural environment characteristics of the highway construction region.

  12. Herbivory enhances positive effects of plant genotypic diversity

    E-print Network

    Agrawal, Anurag

    LETTER Herbivory enhances positive effects of plant genotypic diversity John D. Parker,1 * Juha Both plant diversity and vertebrate herbivores can impact plant fitness and ecosystem functioning, however their interactions have not been explicitly tested. We manipulated plant genotypic diversity

  13. 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…

  14. 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.

  15. 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 ecological change, arthropods may be ideal targets for restoration and conservation activities. PMID:25065640

  16. 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 ?g 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. PMID:25461066

  17. A comparative analysis of methods to represent uncertainty in estimating the cost of constructing wastewater treatment plants

    Microsoft Academic Search

    Ho-Wen Chen; Ni-Bin Chang

    2002-01-01

    Prediction of construction cost of wastewater treatment facilities could be influential for the economic feasibility of various levels of water pollution control programs. However, construction cost estimation is difficult to precisely evaluate in an uncertain environment and measured quantities are always burdened with different types of cost structures. Therefore, an understanding of the previous development of wastewater treatment plants and

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

    SciTech Connect

    Zellmer, S.D. (Argonne National Lab., IL (United States)); Rastorfer, J.R. (Chicago State Univ., IL (United States). Dept. of Biological Sciences ANL/CSU Cooperative Herbarium, Chicago, IL (United States)); Van Dyke, G.D. (Trinity Christian Coll., Palos Heights, IL (United States). 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.

  19. The development of three-dimensional spatial modeling techniques for the construction planning of nuclear power plants

    Microsoft Academic Search

    Harold J. Borkin; Jonn F. McIntosh; James A. Turner

    1978-01-01

    The results are presented of the first phase of a research project on the application of spatial modeling techniques to the process of planning and executing the construction of a nuclear power plant. A computer modeling technique, based on sets of polyhedra and spatial operations, was developed and applied to modeling the components of a nuclear power plant. The objectives

  20. 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.

  1. Effects of herbivore identity on plant fecundity

    Microsoft Academic Search

    Lindsay K. Amsberry; John L. Maron

    2006-01-01

    Herbivores are pervasive, yet their effects on plant fecundity are often variable. One potential source of variation in herbivore impacts results from differing feeding modes of herbivores. We examined the relative importance of inflorescence-feeding insects versus large ungulates in affecting the fecundity of Balsamorhiza sagittata (Asteraceae), a dominant native perennial forb in western Montana, USA. We quantified these effects across

  2. Plant response to Los Angeles aqueduct construction in the Mojave desert

    NASA Astrophysics Data System (ADS)

    Lathrop, Earl W.; Archbold, Edwin F.

    1980-03-01

    Construction of the 1913 Los Angeles aqueduct system had a different effect on vegetation productivity, diversity, and stability in the Mojave Desert than did construction of the 1970 aqueduct. Drastic disturbance was found to impede vegetation recovery, whereas slight disturbance sometimes enhanced vegetation. Comparisons of productivity, diversity, and stability measures for both aqueducts show apparent similarities of vegetation cover, biomass, and density. However, these similarities often vanish when one considers qualitative factors, such as proportion of long-lived species and typical cominants of undisturbed communities. Percentage composition of common long-lived perennials represents a good qualitative measure to supplement quantitative comparisons. Enhancement of vegetation along the right-of-way transects of the 1913 aqueduct shows considerable recovery, owing to the more than 65 years that have passed since construction.

  3. Nutrient removal and plant biomass in a subsurface flow constructed wetland in Brisbane, Australia.

    PubMed

    Browning, K; Greenway, M

    2003-01-01

    Four native plant species (Baumea articulata, Carex fascicularis, Philydrum lanuginosum and Schoenoplectus mucronatus) are being investigated for their suitability in subsurface flow wetlands. The pilot scale Oxley Wetland, Brisbane, consists of 4 cells with different sized gravel (5 mm and 20 mm). The project aims to investigate nutrient removal rates and removal efficiency; nutrient storage in plant biomass; effect of cropping on plant regrowth, and the effect of gravel size on both water treatment and plant growth. Average daily mass removal rates ranged from 7.3 Kgha(-1)d(-1) NH4-N in Cell D to 4.6 Kgha(-1)d(-1) in Cell C i.e. 37%-22% removal efficiency respectively; 5.2 Kgha(-1)d(-1) NOx-N in Cell C to 1.3 Kgha(-1)d(-1) in Cell A (i.e. 75%-22% removal efficiency) and 0.8 Kgha(-1)d(-1) PO4-P in Cell A to 0.1 Kgha(-1)d(-1) in Cell C (i.e. 10%-1% removal efficiency). Cell A was the youngest wetland with new 5 mm gravel. Plant biomass was highest for Baumea and Carex. Gravel size does not appear to have affected biomass and recovery following cropping. Carex consistently had the highest harvested above ground biomass with high re-growth following cropping. Cropping appears to have retarded growth of the other three species with Schoenoplectus consistently having slowest regrowth. Plant biomass and nutrient storage was highest in Cell A and accounted for 11% of nitrogen removal and 3% of phosphorus removal. PMID:14621163

  4. 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 contractor is mentored and supported utilizing the principles of the Construction Industry Institute (CII) Partnering process. Some of the key mentoring and partnering areas that are explored in this paper are, internal and external safety professional support, subcontractor safety teams and the interface with project and site safety teams, quality assurance program support to facilitate compliance with NQA-1, construction, team roles and responsibilities, work definition for successful fixed price contracts, scheduling and interface with project schedules and cost projection/accruals. The practical application of the CII Partnering principles, with the Construction Management expertise of URS, has led to a highly successful construction model that also meets small business contracting goals.

  5. Evaluation of high Ni-Cr-Mo alloys for the construction of sulfur dioxide scrubber plants

    NASA Astrophysics Data System (ADS)

    Rajendran, N.; Rajeswari, S.

    1996-02-01

    Corrosion in wet lime/limestone systems used for flue gas desulfurization in thermal power plants is of great concern. The frequent variations in acidity and in chloride and fluoride ion concentrations experienced by such systems pose a serious threat to the materials of construction. Currently used materials mostly type 316L stainless steel often fail to meet their life expectancy. The present study evaluates the performance of advanced Ni- Cr- Mo alloys 59 and C- 276 in a simulated sulfur dioxide scrubber environment. Accelerated tests showed that high Ni- Cr- Mo alloys have little tendency to leach metal ions such as chromium, nickel, and molybdenum at different impressed potentials. Scanning electron microscopy was used to examine the morphology of pitting attack.

  6. Microgravity effects on plant growth and lignification.

    PubMed

    Cowles, J R; Lemay, R; Jahns, G

    1988-01-01

    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 under 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. PMID:11539286

  7. Effects of plants and plant products on the testis

    Microsoft Academic Search

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

    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

  8. Construction of a bio-test for infecting red clover plants with Sclerotinia trifoliorum.

    PubMed

    Vleugels, T; Baert, J; Van Bockstaele, E

    2011-01-01

    Sclerotinia trifoliorum causes clover cancer in red clover crops. Clover cancer is difficult to control and completely resistant red clover varieties are not available. Breeding for resistant red clover varieties is being slowed down because little is known about the diversity of European S. trifoliorum populations and because of the lack of bio-tests that are useable in breeding programs. The first objective of this research was to develop a reliable high-throughput bio-test, useable in breeding programs. The second objective was to optimise another bio-test, based on isolated leaves, for more precise studies. First, we optimised a method for ascospore production of S. trifoliorum. Once produced, the ascospores were used to evaluate the effects of climate conditions, ascospore concentration and plant age on the high-throughput bio-test. For the bio-test on isolated leaves, the effects of infection method, incubation conditions, incubation period, ascospore concentration, leaf growth stage and mechanical damage were evaluated. In the high-throughput bio-test, disease levels rose with increasing ascospore concentration up to 20,000 spores/ml. The plant age had a small, yet significant effect on the disease level. For the isolated leaf bio-test, the most effective and most repeatable infection method was spraying of an ascospore suspension. Disease levels continued to increase with rising concentrations and incubation time did not interact with plant susceptibility levels. The youngest completely opened leaf yielded the most repeatable results. Both bio-tests were shown to be correlated and could be valuable instruments for breeding programs and for studying plant-pathogen interactions. PMID:22702177

  9. Evaluating Degree of Success in Power Plant Construction Projects Based on Variable Weight Grey Cluster

    Microsoft Academic Search

    Yuansheng Huang; Qingchao Liu; Li Tian

    2008-01-01

    The paper uses variable weight grey cluster to evaluate the degree of success in power plant which is this paperpsilas innovative points. First we give an index system for the project degree of success evaluation, which contains four second-indexes (implementation process, operation situation, financial benefit and the effect of environment) and each second-index contains third-index, then use variable weight grey

  10. Effect of cadmium on symbiotic soybean plants

    Microsoft Academic Search

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

    1981-01-01

    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

  11. UV-B EFFECTS ON TERRESTRIAL PLANTS

    EPA Science Inventory

    The potential impacts of an increase in solar UV-B radiation reaching the Earth's surface due to stratospheric ozone depletion have been investigated by several research groups during the last 15 years. uch of this research has centered on the effects of plant growth and physiolo...

  12. 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

  13. 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

  14. Impact of plant harvest management on function and community structure of nitrifiers and denitrifiers in a constructed wetland.

    PubMed

    Tanaka, Takashi S T; Irbis, Chagan; Wang, Pengyun; Inamura, Tatsuya

    2015-02-01

    Plant harvest is one of the most important management practices in constructed wetlands. In this study, we evaluated the impact of harvesting Phragmites australis (Cav.) Trin. ex Steudel on the activity and community structure of nitrifiers and denitrifiers in a free-water surface constructed wetland. The nitrifiers were targeted using bacterial and archaeal-amoA that encode ammonia monooxygenase, and the denitrifiers were targeted using nirK and nirS that encode the nitrite reductase. The community structures were evaluated using denaturing gradient gel electrophoresis. The potential nitrification and nitrate reduction rates were shown to be significantly higher in the harvested plant rhizosphere than in a non-harvested control plot. The potential nitrification rate positively correlated with the potential nitrate reduction rate and influenced the community structure of nirK. In addition, plant canopy developed differently after harvest and simultaneously changed the microclimate beneath the plant community. These results suggest that plant harvest management could change subsequent plant development and associated microenvironments, thereby affecting the function and community structure of nitrifiers and denitrifiers. Our study highlights the importance of plant harvest management within constructed wetlands to regulate the functions of nitrification and denitrification. PMID:25764547

  15. Field effect transistor and method of construction thereof

    NASA Technical Reports Server (NTRS)

    Fletner, W. R. (inventor)

    1978-01-01

    A field effect transistor is constructed by placing a semi-conductor layer on an insulating substrate so that the gate region is separated from source and drain regions. The gate electrode and gate region of the layer are of generally reduced length, the gate region being of greatest length on its surface closest to the gate electrode. This is accomplished by initially creating a relatively large gate region of one polarity, and then reversing the polarity of a central portion of this gate region by ion bombardment, thus achieving a narrower final gate region of the stated configuration.

  16. Effects of environment and construction procedures on concrete pavement surfaces

    E-print Network

    Wrbas, Ronald Otto

    1972-01-01

    -2 Determination of Evaporation Rate at the Curing Temperature of 73'F and Wind Conditions of 8-10 mph 97 5-3 Determination of. Evaporation Rate at the Curing Tempera'turn of 73 F and Wind Condi tions of 18-20 mph LIST 0F FIGURES (CONT'D. i Figure Page 5... Effects of. Knvironmenj nnd Construction Proce. 'ure. ; on oncretc Pa'camnt Su face;, (Hay 1971) Ronald 0: to Wrbas, B. S. , Texas AKjj Urivexsity Directed by: Dr. William D. Dedbette The quality of the riding surface is the elemcnj of con- struction...

  17. 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 '...

  18. DOE small-scale hydroelectric demonstration project: Riegel Textile Corporation, Fries, Virginia plant hydroproject. Final technical and construction cost report

    SciTech Connect

    Not Available

    1982-06-01

    The Riegel Textile Corporation completed a 2163 kW generator project at its plant in Fries, Virginia. A new powerhouse was constructed to enclose a used 2900 hp vertical Kaplan turbine and Westinghouse generator. Construction was accomplished without modification to or rehabilitation of an existing dam and required only minor modification to or rehabilitation of an existing dam and required only minor modification to the existing appurtenances. The existing hydro-generation equipment supplies approximately 54% of the 5500 kW required by the Fries plant. With the addition of the new facility, the plant will generate approximately 74% of its total electrical requirements. This demonstrates the viability of utilizing hydro-generation in the operation of an industrial facility. The project annually generates a National Energy Savings of 19,387 barrels of oil equivalent. The project was separated into four phases which lasted a total of 36 months and included construction, erection and demonstration.

  19. 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.

  20. 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'. PMID:22591052

  1. Wetlands and Aquatic Processes Temperature and Wetland Plant Species Effects on Wastewater Treatment and Root Zone Oxidation

    Microsoft Academic Search

    Winthrop C. Allen; Paul B. Hook; Joel A. Biederman; Otto R. Stein

    Reviews of operational data for full-scale systems in- dicate that SSWs can meet effluent criteria in cold cli- Constructed wetlands are widely used for wastewater treatment, mates, and that temperature effects on removal of or- but there is little information on processes affecting their performance in cold climates, effects of plants on seasonal performance, or plant ganic matter (OM) may

  2. 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.

  3. Effect of smoke and exhaust on plant growth

    Microsoft Academic Search

    Abeles

    1972-01-01

    Ethylene is a plant hormone, and, therefore, ethylene air pollution has many effects on plant growth and development. Concentrations as low as 0.07 to 0.20 ppm can affect plant growth. Experiments are outlined for the purpose of determining the effects of ethylene from an apple, from auto exhaust, and from cigarette smoke on bean plants.

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

    SciTech Connect

    Munson, D.E.; Matalucci, R.V. [Sandia National Lab., Albuquerque, NM (United States)] [Sandia National Lab., Albuquerque, NM (United States); Hoag, D.L.; Blankenship D.A. [RE/SPEC Inc., Albuquerque, NM (United States)] [and others] [RE/SPEC Inc., Albuquerque, NM (United States); and others

    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.

  5. Ecological effects on effective population size in an annual plant.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient-limited soil can be a strong selective force on plant populations. In addition, ecological factors such as competitive interactions have been shown to have an effect on effective population size (Ne). Both Ne and selection are indicators of population evolutionary processes: selection can...

  6. Assessing the Effectiveness of a Constructed Arctic Stream Using Multiple Biological Attributes

    NASA Astrophysics Data System (ADS)

    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 were not considered and likely constrained success. We suggest that a greater focus on organic characteristics and vegetation within the stream and its riparian zone could have accelerated compensation. The addition of woody debris and CPOM, combined with planting of shrubs and herbs along the stream, should provide a source of allochthonous matter for the biotic community while large cobble and boulders should improve the physical stability of stream system, protecting its organic components.

  7. Influence of UV radiation on chlorophyll, and antioxidant enzymes of wetland plants in different types of constructed wetland.

    PubMed

    Xu, Defu; Wu, Yinjuan; Li, Yingxue; Howard, Alan; Jiang, Xiaodong; Guan, Yidong; Gao, Yongxia

    2014-09-01

    A surface- and vertical subsurface-flow-constructed wetland were designed to study the response of chlorophyll and antioxidant enzymes to elevated UV radiation in three types of wetland plants (Canna indica, Phragmites austrail, and Typha augustifolia). Results showed that (1) chlorophyll content of C. indica, P. austrail, and T. augustifolia in the constructed wetland was significantly lower where UV radiation was increased by 10 and 20 % above ambient solar level than in treatment with ambient solar UV radiation (p < 0.05). (2) The malondialdehyde (MDA) content, guaiacol peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activities of wetland plants increased with elevated UV radiation intensity. (3) The increased rate of MDA, SOD, POD, and CAT activities of C. indica, P. australis, and T. angustifolia by elevated UV radiation of 10 % was higher in vertical subsurface-flow-constructed wetland than in surface-flow-constructed wetland. The sensitivity of MDA, SOD, POD, and CAT activities of C. indica, P. austrail, and T. augustifolia to the elevated UV radiation was lower in surface-flow-constructed wetland than in the vertical subsurface-flow-constructed wetland, which was related to a reduction in UV radiation intensity through the dissolved organic carbon and suspended matter in the water. C. indica had the highest SOD and POD activities, which implied it is more sensitive to enhanced UV radiation. Therefore, different wetland plants had different antioxidant enzymes by elevated UV radiation, which were more sensitive in vertical subsurface-flow-constructed wetland than in surface-flow-constructed wetland. PMID:24788860

  8. Construction of a plant-transformation-competent BIBAC library and genome sequence analysis of polyploid Upland cotton (Gossypium hirsutum L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton is a world’s leading crop important to the world’s textile and energy industries, and a model species for studies of plant polyploidization, cellulose biosynthesis and cell wall biogenesis. Here, we report the construction and extensive analysis of a binary bacterial artificial chromosome (BI...

  9. Formulation of production blasting criteria for the construction of a lime plant at a major crushed stone operation

    Microsoft Academic Search

    Paul Worsey; Scott G. Giltner; Terry Drechsler; Ron Ecklecamp; Ronnie Inman

    1998-01-01

    A blast-monitoring program conducted at Chemical Lime Company's new lime calcining facility near St Genevieve, Missouri, USA is discussed. The purpose was to develop blasting criteria for the construction and operation of the lime plant within the quarry operated by Tower Rock Stone. Further, it was imperative to accommodate production requirements into the blasting criteria. The major concern was the

  10. WELL CONSTRUCTION AND PURGING EFFECTS ON GROUND-WATER SAMPLES

    EPA Science Inventory

    Multiple well installations of selected casing materials (i.e., polytetrafluoroethylene (PTFE), 304 stainless steel (SS), and polyvinyl chloride (PVC)) were constructed and sampled to determine if well purging and construction procedures would significantly bias chemical constitu...

  11. Effectiveness of Infection Control Barriers for Construction in Healthcare

    E-print Network

    Huo, Jinyun

    2014-08-12

    are transmitted on dust particles, to reduce the risk of fatal infections. Infection control barriers have been largely adopted for new hospital construction at an existing facility to reduce the incidence of infections caused by construction dust borne pathogens...

  12. 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. PMID:24956804

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

    PubMed

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

    2009-08-01

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

  14. 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.

  15. 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

  16. Structure and function of denitrifying and nitrifying bacterial communities in relation to the plant species in a constructed wetland.

    PubMed

    Ruiz-Rueda, Olaya; Hallin, Sara; Bañeras, Lluis

    2009-02-01

    The community structure and potential activities of nitrifying and denitrifying bacteria were studied in the rhizosphere of Typha latifolia and Phragmites australis present in a free water system constructed wetland (CW). Potential nitrate reduction and nitrification activities were shown to be significantly higher in the rhizosphere when compared with the nonvegetated sediment. Higher rates were generally obtained for P. australis. The community structure of denitrifying bacteria in the rhizosphere differed from that found at the bulk sediment, as revealed by PCR-denaturing gradient gel electrophoresis (DGGE) of the nitrous oxide reductase encoding gene nosZ. Results also show a greater nosZ genotype diversification and suggest a plant species effect in rhizosphere samples obtained during events of low hydraulic retention times. Ammonia-oxidizing communities were less complex on the basis of PCR-DGGE analysis of the 16S rRNA gene. Retrieved sequences were all related to Nitrosomonas marina and Nitrosomonas ureae, being both present in rhizosphere and bulk sediment regardless of environmental changes. The results demonstrate the effect of vegetation on the functioning and structure of bacterial communities involved in the removal of nitrogen in the treatment cells of a CW and point to the use of vegetation coverage to promote nitrification or denitrification in particular areas. PMID:19049502

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

    PubMed Central

    Liczner, Amanda R.

    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. PMID:24688848

  18. agronomie: plant genetics and breeding Effect of arbuscular mycorrhizal inoculation

    E-print Network

    Paris-Sud XI, Université de

    agronomie: plant genetics and breeding Effect of arbuscular mycorrhizal inoculation plants were inoculated at acclimatization stage with two types of inoculum of Glomus fasciculatum between the two types of inoculum to the extent of plant root colonization as it affects plant sur- vival

  19. REGULAR ARTICLE Earthworm effects on plant growth do not necessarily

    E-print Network

    Boyer, Edmond

    REGULAR ARTICLE Earthworm effects on plant growth do not necessarily decrease with soil fertility + Business Media B.V. 2009 Abstract Earthworms are known to generally increase plant growth. However, because plant-earthworm inter- actions are potentially mediated by soil characteristics the response of plants

  20. The cost effectiveness of geotechnical investigations in commercial building construction

    E-print Network

    Temple, Merdith Wyndham Bolling

    1985-01-01

    Construction. (May 1 985) Merdith Wyndham Boiling Temple, B. S. , Virginia Military Institute Chairman of Advisory Committee: Dr. George Stukhart The purpose of a construction geotechni eel investigation is to provide soil property data for the design... TA 63 69 71 75 79 83 89 91 vl i i LIST OF FIGURES Number Page 1. The Leaning Tower of Pisa 2. Pre-const ruction Phases of Project Development Locations of Texas Projects 16 38 4. Construction Cost vs. Geotechnical Investigation Cost...

  1. 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.

  2. Cytotoxic Effects of Bangladeshi Medicinal Plant Extracts

    PubMed Central

    Uddin, Shaikh J.; Grice, I. Darren; Tiralongo, Evelin

    2011-01-01

    To investigate the cytotoxic effect of some Bangladeshi medicinal plant extracts, 16 Bangladeshi medicinal plants were successively extracted with n-hexane, dichloromethane, methanol and water. The methanolic and aqueous extracts were screened for cytotoxic activity against healthy mouse fibroblasts (NIH3T3) and three human cancer-cell lines (gastric: AGS; colon: HT-29; and breast: MDA-MB-435S) using the MTT assay. Two methanolic extracts (Hygrophila auriculata and Hibiscus tiliaceous) and one aqueous extract (Limnophila indica) showed no toxicity against healthy mouse fibroblasts, but selective cytotoxicity against breast cancer cells (IC50 1.1–1.6?mg?mL?1). Seven methanolic extracts from L. indica, Clerodendron inerme, Cynometra ramiflora, Xylocarpus moluccensis, Argemone mexicana, Ammannia baccifera and Acrostichum aureum and four aqueous extracts from Hygrophila auriculata, Bruguiera gymnorrhiza, X. moluccensis and Aegiceras corniculatum showed low toxicity (IC50 > 2.5?mg?mL?1) against mouse fibroblasts but selective cytotoxicity (IC50 0.2–2.3?mg?mL?1) against different cancer cell lines. The methanolic extract of Blumea lacera showed the highest cytotoxicity (IC50 0.01–0.08?mg?mL?1) against all tested cell lines among all extracts tested in this study. For some of the plants their traditional use as anticancer treatments correlates with the cytotoxic results, whereas for others so far unknown cytotoxic activities were identified. PMID:19706693

  3. INDIAN PLANTS AND PLANT PRODUCTS WITH ANTIFERTILITY EFFECT*

    PubMed Central

    Satyavati, G. V.

    1984-01-01

    In this article the author reviews research studies on Indian plants with antifertility activity conducted by different Institutes and independent investigators. The available clinical data is also present here. PMID:22557405

  4. Evaluating the economic effectiveness of a cogeneration plant

    SciTech Connect

    Korik, L.; Yeaple, D.: Hajosy, M. [Medical Area Total Energy Plant, Boston, MA (United States)

    1996-08-01

    Economic considerations constitute the major factor in the decision to build a cogeneration plant and to its eventual design - topics which have been the focus of many studies and papers. These economic concerns continue when the plant is built and on-line, thus plant operation must be geared to provide the customers` demand in the most economically effective manner possible. Unfortunately, the complexity of and high degree of interaction between the disparate components of a cogeneration plant oftentimes, make it difficult to conceptualize the plant configuration required to maximize plant economic performance for a given demand, Indeed, actions taken to increase the thermal performance of individual plant components can actually decrease the overall economic effectiveness of the plant as a whole in the context of converting fuels to sendouts. What is needed, then, is a way to meld the performance of individual plant components into a total plant performance index that accurately measures the economic effectiveness of the plant. This paper details such a method developed by the Cogeneration Management Company to accomplish the performance evaluation of its Medical Area Total Energy Plant which supplies electricity, steam, and chilled water to the Longwood. Medical Area in Boston, This method - which is easily adapted to a variety of cogeneration designs - addresses the aforementioned complexities in the assessing of a cogeneration plant`s effectiveness and results in simple-to-understand plant performance quantifications which have proved to be of great utility in ensuring the economically sound operation of MATEP.

  5. 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 of soil profiles is therefore an innovative way of monitoring and quantifying the impact of pedogenetic factors on the evolution of Technosols.

  6. Physiological effects of humic substances on higher plants

    Microsoft Academic Search

    Serenella Nardi; Diego Pizzeghello; Adele Muscolo; Angelo Vianello

    2002-01-01

    The physiological effects of humic substances (HS) on some aspects of plant growth and metabolism are examined. Evidence has been presented on that the effect of HS on plant growth depends on the source, concentration and molecular weight humic fraction. While a low molecular size (LMS<3500Da) fraction easily reaches the plasmalemma of higher plant cells and, in part, is taken

  7. 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. PMID:12531364

  8. Effectiveness of Medicinal Plant Conservation Areas in Western Ghats, India

    E-print Network

    Barve, Narayani

    2014-04-25

    Effectiveness of Medicinal Plant Conservation Areas in Western Ghats, India Narayani Barve Medicinal Plant Conservation Areas (MPCA) ? Designated by State Forest Department ? Established early 1990s ? Network of 200 sites all over India... ? Selection based on Plant diversity and known medicinal plant hotspots The Western Ghats (Sahyadri) Biodiversity Hotspot ? Less than 6% of the land area of India, but contains more than 30% of all plant, bird, and mammal species found in the country...

  9. 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)

  10. [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). PMID:25739280

  11. Comparative analysis of United States and French nuclear power plant siting and construction regulatory policies and their economic consequences

    E-print Network

    Golay, Michael Warren.

    1977-01-01

    Despite the substantial commitments of time and money which are devoted to the nuclear power plant siting process, the effectiveness of the system in providing a balanced evaluation of the technical, environmental and ...

  12. Bioconcentration of triclosan, methyl-triclosan, and triclocarban in the plants and sediments of a constructed wetland.

    PubMed

    Zarate, Frederick M; Schulwitz, Sarah E; Stevens, Kevin J; Venables, Barney J

    2012-07-01

    Constructed wetlands are a potential method for the removal of two pharmaceutical and personal care products from wastewater effluent. Triclosan (TCS; 5-chloro-2-[2,4-dichlorophenoxy]phenol) and triclocarban (TCC; 3,4,4'-trichlorocarbanillide) are antimicrobial agents added to a variety of consumer products whose accumulation patterns in constructed wetlands are poorly understood. Here, we report the accumulation of TCS, its metabolite methyl-triclosan (MTCS; 5-chloro-2-[2,4-dichlorophenoxy]), and TCC in wetland plant tissues and sediments. Three wetland macrophytes: Typha latifolia, Pontederia cordata, and Sagittaria graminea were sampled from a constructed wetland in Denton, Texas, USA. MTCS concentrations were below the method detection limit (MDL) for all species. TCS root tissue concentrations in T. latifolia were significantly greater than root concentrations in P. cordata (mean±SE in ng g(-1): 40.3±11.3 vs. 15.0±1.9, respectively), while for TCC, shoot tissue concentrations in S. graminea were significantly greater than in T. latifolia (22.8±9.3 vs. 9.0 (MDL), respectively). For both TCS and TCC, T. latifolia root tissue concentrations were significantly greater than shoot concentrations (TCS: 40.3±11.3 vs. 17.2±0.2, TCC: 26.0±3.6 vs. 9.0, (MDL)). TCC concentrations in P. cordata roots were significantly greater than in shoots (34.4±5.3 vs. 15.4±2.8, respectively). TCS concentrations in T. latifolia roots and sediments and TCC concentrations in sediments generally decreased from wetland inflow to outflow. To our knowledge, this is the first study documenting species and tissue specific differences in the accumulation of TCS and TCC in plants from an operational constructed wetland. The species specific differences in bioaccumulation suggest TCS and TCC removal from constructed wetlands could be enhanced through targeted plantings. PMID:22483729

  13. Additive and interactive effects of plant genotypic diversity on arthropod communities and plant fitness

    E-print Network

    Agrawal, Anurag

    LETTER Additive and interactive effects of plant genotypic diversity on arthropod communities@botany.utoronto.ca Abstract Recent research suggests that genetic diversity in plant populations can shape the diversity species of naturally colonizing arthropods. Genetically diverse plant patches had 18% more arthropod

  14. Modelling Plant Compensatory Effects in Plant-Insects dynamics

    E-print Network

    Paris-Sud XI, Université de

    of living organisms to control pest invasions, is booming in crop protection. If the part of biological-insect interactions, plant compensation, bifurcation diagram I. INTRODUCTION Biological control, i.e. the use and the discovery of new biological control agents has increased the percentage to 2.5%. Biological control programs

  15. [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

  16. [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

  17. Andrew Ford 1 CEC Report Simulating Patterns of Power Plant Construction

    E-print Network

    Ford, Andrew

    " with a shelf life of 24 months. If the project does not begin construction within 24 months, the permit expires the development process beginning with the formal application for a construction permit. The agencies review gas. The base case begins with a peak demand of 46 GW and gas priced at 2.50 $/million BTU. Demand

  18. 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…

  19. 76 FR 6811 - Endangered and Threatened Wildlife and Plants; Permit; Construction and Operation of Kaheawa II...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-08

    ...Construction and Operation of Kaheawa II Wind Energy Generation Facility, Maui...receipt of an application from Kaheawa Wind Power II, LLC (KWP II) for an incidental...construction and operation of the KWP II wind energy facility on the island of...

  20. A commercial project for private investments. Update of the 280 MW api Energia IGCC plant construction in central Italy.

    SciTech Connect

    Del Bravo, R.; Pinacci, P.; Trifilo, R.

    1998-07-01

    This paper has the aim to give a general overview of the api Energia IGCC project starting from the project background in 1992 and ending with the progress of construction. api Energia S.p.A., a joint VENTURE between api anonima petroli italiana S.p.A., Roma, Italy (51%), ABB Sae Sadelmi S.p.A., Milano, Italy (25%) and Texaco Development Corporation (24%), is building a 280 MW Integrated Gasification Combined Cycle plant in the api refinery at Falconara Marittima, on Italy' s Adriatic coast, using heavy oil residues. The plant is based on the modern concept of employing a highly efficient combined cycle power plant fed with a low heating value fuel gas produced by gasifying heavy refinery residues. This scheme provides consistent advantages in terms of efficiency and environmental impact over alternative applications of the refinery residues. The electric power produced will feed the national grid. The project has been financed using the ``project financing'' scheme: over 1,000 billion Lira, representing 75% of the overall capital requirement, have been provided by a pool of international banks. In November 1996 the project reached financial closure and immediately after the detailed design and procurement activities started. Engineering, Procurement and Construction activities, carried out by a Consortium of companies of the ABB group, are totally in line with the schedule. Commercial operation of the plant, is scheduled for November 1999.

  1. [Obtaining marker-free transgenic soybean plants with optimal frequency by constructing three T-DNAs binary vector].

    PubMed

    Ye, Xing-Guo; Qin, Hua

    2007-01-01

    Obtaining marker-free plants with high efficiency will benefit the environmental release of transgenic crops. To achieve this point, a binary vector pNB35SVIP1 with three T-DNAs was constructed by using several mediate plasmids, in which one copy of bar gene expression cassette and two copies of VIP1 gene expression cassette were included. EHA101 Agrobacterium strain harboring the final construct was applied to transform soybean (Glycine max) cotyledon nodes. Through 2 - 3 months regeneration and selection on 3 - 5mg/L glufosinate containing medium, transgenic soybean plants were confirmed to be obtained at 0.83% - 3.16%, and co-transformation efficiency of both gene in the same individual reached up to 86.4%, based on southern blot test. By the analysis of PCR, southern blot and northern blot combining with leaf painting of herbicide in T1 progenies, 41 plants were confirmed to be eliminated of bar gene with the frequency of 7.6% . Among the T1 populations tested, the loss of the alien genes happened in 22.7% lines, the silence of bar gene took place in 27.3% lines, and VIP1 gene silence existed in 37.1% marker-free plants. The result also suggested that the plasmid with three T-DNAs might be an ideal vector to generate maker-free genetic modified organism. PMID:17366903

  2. 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.

  3. 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.…

  4. Constructed Tropical Wetlands with Integrated Submergent-Emergent Plants for Sustainable Water Quality Management

    Microsoft Academic Search

    NORIO TANAKA; K. B. S. N. JINADASA; D. R. I. B. WERELLAGAMA; M. I. M. MOWJOOD; W. J. NG

    2006-01-01

    Improvement of primary effluent quality by using an integrated system of emergent plants (Scirpus grossus in the leading subsurface flow arrangement) and submergent plants (Hydrilla verticillata in a subsequent channel) was investigated. The primary effluent was drawn from a septic tank treating domestic sewage from a student dormitory at the University of Peradeniya, Sri Lanka. Influent and effluent samples were

  5. Supply strategy and network effects — purchasing behaviour in the construction industry

    Microsoft Academic Search

    Anna Dubois; Lars-Erik Gadde

    2000-01-01

    Partnering with suppliers and networking are increasingly used as means to improve company performance. This paper explores the occurrence of network effects in the construction industry. Benefits from network effects arise when firms adapt to one another in terms of technical solutions, logistics or administrative routines. The study finds such effects to be unusual in the construction industry. The main

  6. EFFECTS OF ACID PRECIPITATION ON PLANT DISEASES

    EPA Science Inventory

    Most plant diseases consist of delicate interactions between higher plants and microorganisms. Acidic precipitation represents an environmental stress that has been shown to affect expected development of some diseases and similar phenomena under experimental conditions. From the...

  7. 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. PMID:24339034

  8. 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.

  9. Plant pathology Effect of nitrate on acetylene reduction

    E-print Network

    Paris-Sud XI, Université de

    Plant pathology Effect of nitrate on acetylene reduction and the activities of some enzymes October 1990) Summary — Soybean plants (Glycine max (L) Merr) cv Maple arrow were nodulated either infected by B japonicum USDA 311 b 138. Thus infecting soybean plants with either B japonicum USDA 311 b

  10. Effects on air pollutant removal by plant absorption and adsorption

    Microsoft Academic Search

    Shuji Fujii; Hiun Cha; Naoki Kagi; Hisashi Miyamura; Yong-Shik Kim

    2005-01-01

    It is well known that plants aid the removal of air pollutants. On the other hand, there is little research on air purification capabilities of absorption and disintegration of the air pollutants by plants. This research observes the air purification effect of plants' absorption capabilities of carbon dioxide (CO2) and nitrogen oxides (NOX) with the aim of quantifying air purification

  11. Herbivory: effects on plant abundance, distribution and population growth

    Microsoft Academic Search

    John L. Maron; Elizabeth Crone

    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

  12. “Afterlife” effects of mycorrhization on the decomposition of plant residues

    Microsoft Academic Search

    Martin Schädler; Roland Brandl; Anne Kempel

    2010-01-01

    The symbiosis with arbuscular mycorrhizal fungi is known to affect growth and tissue quality of plants. Therefore, mycorrhization may also have “afterlife” effects on decomposition dynamics. We tested this hypothesis with plant material of mycorrhized and non-mycorrhized plants of seven grassland species. We found that mycorrhization increased the decomposition rate and interpret this result as a consequence of the enhanced nutritive

  13. Constructed tropical wetlands with integrated submergent-emergent plants for sustainable water quality management.

    PubMed

    Tanaka, Norio; Jinadasa, K B S N; Werellagama, D R I B; Mowjood, M I M; Ng, W J

    2006-01-01

    Improvement of primary effluent quality by using an integrated system of emergent plants (Scirpus grossus in the leading subsurface flow arrangement) and submergent plants (Hydrilla verticillata in a subsequent channel) was investigated. The primary effluent was drawn from a septic tank treating domestic sewage from a student dormitory at the University of Peradeniya, Sri Lanka. Influent and effluent samples were collected once every 2 weeks from May 2004 through July 2005 and analyzed to determine water quality parameters. Both the emergent and submergent plants were harvested at predetermined intervals. The results suggested that harvesting prolonged the usefulness of the system and the generation of a renewable biomass with potential economic value. The mean overall pollutant removal efficiencies of the integrated emergent and submergent plant system were biological oxygen demand (BOD5), 65.7%; chemical oxygen demand (COD), 40.8%; ammonium (NH4+-N), 74.8%; nitrate (NO3--N), 38.8%; phosphate (PO43-), 61.2%; total suspended solids (TSS), 65.8%; and fecal coliforms, 94.8%. The submergent plant subsystem improved removal of nutrients that survived the emergent subsystem operated at low hydraulic retention times. The significant improvement in effluent quality following treatment by the submergent plant system indicates the value of incorporating such plants in wetland systems. PMID:17018409

  14. Passing Vakhsh river flows during construction of the Nurek hydroelectric plant

    Microsoft Academic Search

    Yu. K. Sevenard; B. A. Nikolaev; I. S. Redchenko; F. F. Svintsov; Ya. G. Chobanis; N. A. Chernovol

    1979-01-01

    Conclusion  The scheme developed for operating high-head segmented gates on eccentric supports by means of temporary installations, as has been highly recommended, may also be employed on other construction projects in similar situations.

  15. Plant species as a significant factor in wastewater treatment in constructed wetlands

    E-print Network

    Varvel, Tracey W

    2013-02-22

    Constructed wetlands are one of the newest wastewater treatment technologies. They should reduce the Biochemical Oxygen Demand (BOD) and utilize a large amount of the influent. The BOD determines how much oxygen is used bymicro organisms while...

  16. 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

  17. 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

  18. [Analysis of microorganism species diversity in plant intercropping models in a wetland system constructed for treatment of municipal sewage].

    PubMed

    Chen, Yong-Hua; Wu, Xiao-Fu; Chen, Ming-Li; Zhang, Zhen-Ni; Li, Ke-Lin; Wang, Zhong-Cheng; Lei, Dian

    2011-08-01

    The selective culture method and PCR-DGGE technology were applied to analyze the number and the biodiversity of microorganism species in cells with plant intercropping models and without plants in different seasons in a wetland system constructed for treatment of municipal sewage. The results showed that the numbers of microorganisms were considerably larger in the cells with plant intercropping models than those without plants, while the number of microorganisms was apparently larger in summer than that in winter in all treatments. Along the three-sequenced treatment cells with plant intercropping models a "low-high-low" changing trend in the numbers of microorganisms in summer. The UPGMA cluster analysis showed that the treatments in the same season were clustered in the same branch except for a few samples in winter and the biodiversity index was consistently higher in summer than that in winter. Five different sequences (DF1-DF5) were obtained through BLAST analysis and retrieval. The closest known origin groups were located as Escherichia coli, Citrobacter sp., Proteus sp., Klebsiella oxytoca, and Burkholderia sp. respectively. The BLASTX comparison test showed that DF1 closely related to the activities of the Mycobacterium bacillus and the Bacillus amyloliquefaciens, DF2 functioned as a conservative potential ATP binding protein, DF3 related to the activities of the Bacillus cereus spore, DF4 was involved in catabolism metabolism of microorganism and DF5 played an important role in decomposition of organic matters. PMID:22619969

  19. 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

  20. 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...

  1. 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...

  2. An examination of the pursuit of nuclear power plant construction projects in the United States

    E-print Network

    Guyer, Brittany (Brittany Leigh)

    2011-01-01

    The recent serious reconsideration of nuclear power as a means for U.S. electric utilities to increase their generation capacity provokes many questions regarding the achievable success of future nuclear power plant ...

  3. 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...

  4. Efficient construction of plant genomic libraries requires the use of mcr host strains and packaging mixes

    Microsoft Academic Search

    Michael W. Graham; Judith P. Doherty; David M. Woodcock

    1990-01-01

    It has recently become apparent that many strains ofE. coli contain nucleases encoded by themcrA andmcrB loci that, recognize the modified base 5-methylcytosine in DNA. Plant DNAs have particularly high levels of this modification\\u000a and the activity of these 5-methylcytosine-specific nucleases is particularly relevant to cloning plant genomic DNAs. We show\\u000a here that for preparing libraries in a ? replacement

  5. Construction and Maintenance of the Optimal Photosynthetic Systems of the Leaf, Herbaceous Plant and Tree: an Eco-developmental Treatise

    PubMed Central

    TERASHIMA, ICHIRO; ARAYA, TAKAO; MIYAZAWA, SHIN-ICHI; SONE, KOSEI; YANO, SATOSHI

    2004-01-01

    • Background and Aims The paper by Monsi and Saeki in 1953 (Japanese Journal of Botany 14: 22–52) was pioneering not only in mathematical modelling of canopy photosynthesis but also in eco-developmental studies of seasonal changes in leaf canopies. • Scope Construction and maintenance mechanisms of efficient photosynthetic systems at three different scaling levels—single leaves, herbaceous plants and trees—are reviewed mainly based on the nitrogen optimization theory. First, the nitrogen optimization theory with respect to the canopy and the single leaf is briefly introduced. Secondly, significance of leaf thickness in CO2 diffusion in the leaf and in leaf photosynthesis is discussed. Thirdly, mechanisms of adjustment of photosynthetic properties of the leaf within the herbaceous plant individual throughout its life are discussed. In particular, roles of sugar sensing, redox control and of cytokinin are highlighted. Finally, the development of a tree is considered. • Conclusions Various mechanisms contribute to construction and maintenance of efficient photosynthetic systems. Molecular backgrounds of these ecologically important mechanisms should be clarified. The construction mechanisms of the tree cannot be explained solely by the nitrogen optimization theory. It is proposed that the pipe model theory in its differential form could be a potential tool in future studies in this research area. PMID:15598701

  6. Construction of a cDNA library from the ephemeral plant Olimarabidopsis pumila and preliminary analysis of expressed sequence tags.

    PubMed

    Zhao, Yun-Xia; Wei, Yan-Ling; Zhao, Ping; Xiang, Cheng-Bin; Xu, Fang; Li, Chao; Huang, Xian-Zhong

    2013-01-01

    Olimarabidopsis pumila is a close relative of the model plant Arabidopsis thaliana but, unlike A. thaliana, it is a salt-tolerant ephemeral plant that is widely distributed in semi-arid and semi-salinized regions of the Xinjiang region of China, thus providing an ideal candidate plant system for salt tolerance gene mining. A good-quality cDNA library was constructed using cap antibody to enrich full-length cDNA with the gateway technology allowing library construction without traditional methods of cloning by use of restriction enzymes. A preliminary analysis of expressed sequence tags (ESTs) was carried out. The titers of the primary and the normalized cDNA library were 1.6 x 10(6) cfu/mL and 6.7 x 10(6) cfu/mL, respectively. A total of 1093 clones were randomly selected from the normalized library for EST sequencing. By sequence analysis, 894 high-quality ESTs were generated and assembled into 736 unique sequences consisting of 72 contigs and 664 singletons. The resulting unigenes were categorized according to the gene ontology (GO) hierarchy. The potential roles of gene products associated with stress-related ESTs are discussed. The 736 unigenes were similar to A. thaliana, A. lyrata, or Thellungiella salsuginea. This research provides an overview of the mRNA expression profile and first-hand information of gene sequence expressed in young leaves of O. pumila. PMID:24601088

  7. 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 ancillary socio-economic, ecosystem, and water treatment/polishing benefits when used to complement water resources at thermoelectric power plants. Through the Phase II pilot study segment of the contract, the project team partnered with Progress Energy Florida (now Duke Energy Florida) to quantify the wetland water cooling benefits at their Hines Energy Complex in Bartow, Florida. The project was designed to test the wetland’s ability to cool and cleanse power plant cooling pond water while providing wildlife habitat and water harvesting benefits. Data collected during the monitoring period was used to calibrate a STELLA model developed for the site. It was also used to inform management recommendations for the demonstration site, and to provide guidance on the use of cooling wetlands for other power plants around the country. As a part of the pilot study, Duke Energy is scaling up the demonstration project to a larger, commercial scale wetland instrumented with monitoring equipment. Construction is expected to be finalized in early 2014.

  8. 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

  9. Solitary confinement of prisoners: An assessment of its effects on inmates' personal constructs and adrenocortical activity

    Microsoft Academic Search

    C. E. Ecclestone; Paul Gendreau; Clifford Knox

    1974-01-01

    Examined the effects of 10 days prison solitary confinement on inmates' personal constructs and adrenocortical activity. 8 Ss maintained their regular institutional routine and 8 Ss were placed for 10 days in solitary confinement. Personal construct rankings (measured by the repertory grid technique) increased in stability for confined Ss compared to nonconfined Ss. This effect was more pronounced for \\

  10. Design and performance of a large, field exposure chamber to measure effects of air quality on plants

    Microsoft Academic Search

    A. S. Heagle; R. B. Philbeck; R. E. Ferrell; W. W. Heck

    2009-01-01

    A 4.66-m diam., 3.6 m tall, cylindrical open-top field chamber was designed, constructed, and tested as a tool to measure the effects of air quality on plant function and yield. It is a larger version of the 3-m diam. chamber that has been used to measure the effects of gaseous pollutants on crop plants. The new chamber has an aluminum-channel

  11. 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

  12. Grazing effects on plant functional group diversity in Mediterranean shrublands

    Microsoft Academic Search

    Alexandra D. Papanikolaou; Nikolaos M. Fyllas; Antonios D. Mazaris; Panayiotis G. Dimitrakopoulos; Athanasios S. Kallimanis; John D. Pantis

    Grazing is one of the prevalent human activities that even today are taking place inside protected areas with direct or indirect\\u000a effects on ecosystems. In this study we analyzed the effects of grazing on plant species diversity, plant functional group\\u000a (PFG) diversity and community composition of shrublands. We analyzed plant diversity data from 582 sampling plots located\\u000a in 66 protected

  13. Herbivory enhances positive effects of plant genotypic diversity.

    PubMed

    Parker, John D; Salminen, Juha-Pekka; Agrawal, Anurag A

    2010-05-01

    Both plant diversity and vertebrate herbivores can impact plant fitness and ecosystem functioning, however their interactions have not been explicitly tested. We manipulated plant genotypic diversity of the native plant Oenothera biennis and monitored its survivorship and lifetime fitness with and without one of its major vertebrate consumers, white-tailed deer Odocoileus virginianus. Intense but unmanipulated herbivory by meadow voles Microtus pennsylvanicus killed over 70% of nearly 4000 experimental plants. However, plants grown in genotypically diverse patches suffered fewer vole attacks and had higher survival and reproductive output than plants in monoculture. Moreover, positive effects of genotypic diversity were enhanced by the presence of deer, indicating a non-additive interaction between diversity and trophic-level complexity. Genetic selection analyses showed that the selective value of ecologically important traits depended on plant diversity and exposure to deer, demonstrating that community complexity can promote fitness through multiple ecologically and evolutionarily important feedbacks. PMID:20298460

  14. Decreasing unpalatable flavonoid components in Citrus: the effect of transformation construct.

    PubMed

    Koca, Ufuk; Berhow, Mark A; Febres, Vicente J; Champ, Karen I; Carrillo-Mendoza, Omar; Moore, Gloria A

    2009-10-01

    Citrus species accumulate large quantities of flavanone glycosides in their leaves and fruit. The physiological role(s) of these compounds in citrus plants are unknown, but they have been documented to benefit human health upon consumption. Flavanone rutinosides are tasteless, whereas flavanone neohesperidosides, such as naringin, give a bitter taste to fruit and fruit juice products, reducing their palatability. In an effort to alter the types and levels of flavanone neohesperidosides in citrus, an Agrobacterium-mediated genetic transformation approach was employed. Citrus paradisi Macf. (grapefruit) epicotyl stem segments were transformed with sense (S) and antisense (AS) constructs of the target genes chalcone synthase (CHS) and chalcone isomerase (CHI), whose products catalyze the first two steps in the flavonoid biosynthetic pathway. Transformation with each of the individual constructs led to a different and unpredictable combination of viability, phenotypic change, transgene steady-state expression and alteration in flavonoid content in the resulting transgenic plants. These qualities were consistent within the transgenic plants obtained using any particular construct. Transgenic plants with decreased leaf naringin levels were obtained, particularly when the CHS-AS constructs were employed. PMID:19656329

  15. SINTER PLANT WINDBOX RECIRCULATION AND GRAVEL BED FILTER DEMONSTRATION. PHASE 2. CONSTRUCTION, OPERATION, AND EVALUATION

    EPA Science Inventory

    The report gives results of phase 2 of a program to demonstrate new technology for reducing exhaust gas volume and controlling emissions from the steel industry sintering process. Phase 2 entailed construction, operation, and evaluation of the system and, in addition, the constru...

  16. Plant pathology Effects of adjuvants on herbicidal action.

    E-print Network

    Paris-Sud XI, Université de

    Plant pathology Effects of adjuvants on herbicidal action. I. Effects of a mixture of adjuvants herbicide penetration in both species: 2 to 3 times in ryegrass and 4 to 11 times in wheat, ac- cording lead to an increase in herbicide entry into the plants, which explains the higher efficacy

  17. Differing Effects of Cattle Grazing on Native and Alien Plants

    Microsoft Academic Search

    SARAH KIMBALL; PAULA M. SCHIFFMAN

    2003-01-01

    Habitat managers use cattle grazing to reduce alien plant cover and promote native species in California grasslands and elsewhere in the western United States. We tested the effectiveness of grazing as a restoration method by examining the effects of herbivory on native and alien plants. At Carrizo Plain National Monument, California, we surveyed native and alien species cover in adjacent

  18. Air pollution oxidants - their effects on metabolic processes in plants

    Microsoft Academic Search

    W. M. Dugger; I. P. Ting

    1970-01-01

    With the exception of exposures to ambient air, most investigations concerning the effect of pollutants on plant growth and development have been conducted with single pollutants. Recently, reports have appeared of synergistic effects of ozone and sulfur dioxide. Plants exposed to ozone and SOâ singly at subthreshold levels were not affected, but when they were exposed in combination, damage was

  19. Plant species effects on soil nematode communities in experimental grasslands

    Microsoft Academic Search

    Maria Viketoft; Cecilia Palmborg; Björn Sohlenius; Kerstin Huss-Danell; Jan Bengtsson

    2005-01-01

    We examined the effects of 12 different plant species on soil nematode abundance and community composition, and rotifer abundance, in an experimental grassland in Northern Sweden. Monocultures were grown for six or seven growing seasons before sampling. Four monocultures were grasses, four were legumes and four were non-leguminous forbs. Plant species identity had an effect on the nematode community, both

  20. EFFECTS OF POLLUTANTS ON SUBMARINE PLANT SYNECOLOGY

    EPA Science Inventory

    Synecology of marine plant communities has been studied in areas differing in water quality. Major sources of deterioration of water quality include the Nooksack River, an oil refinery and an alumina reduction plant. A method of analysis involving comparisons of standing crops of...

  1. Solar One - 10-MWe solar central receiver power plant Lessons learned in design, construction, and start-up

    NASA Astrophysics Data System (ADS)

    Bigger, J. E.; Criner, D. E.; Gould, G. L.; Skvarna, P. A.

    1983-09-01

    Practical aspects of solar-power-plant design, construction, and operation are examined in a survey of the Solar One central-receiver project in Barstow, California, from its authorization in 1975 through the initial months of normal operation in late 1982. The organization and management of the project is sketched, and the plant systems are characterized: 1818-heliostat microprocessor-controlled collector, 800-tube 302-sq m receiver capable of delivering 51,000 kg/h of steam at 516 C and 10.1 MPa, thermocline-tank thermal-storage system, master control, beam-characterization system, conventional Rankine steam-turbine generator, and support systems. The technical, control, and management lessons learned in the progress of the project are discussed individually. Preliminary operational data indicate that Solar One will not meet the design goal of 26 GW h net average annual generation, primarily due to unexpectedly high auxiliary power consumption by the plant itself. The need to optimize plants for minimum auxiliary power requirements, especially during shutdown periods, is indicated.

  2. Evaluating Degree of Success in Power Plant Construction Project Based on Fuzzy Neural Network

    Microsoft Academic Search

    Yuansheng Huang; Qingchao Liu; Zilong Qiu; Mingyan Wang

    2008-01-01

    Using fuzzy neural network to evaluate the degree of success in power plant is this paper's innovative points. First we give an index system, and then use the relative membership degree processing the date, which as the input sample of neural network. Then use PSO algorithm optimizes the BP neural network algorithm. Use this improved BP neural network to evaluate.

  3. Development of Advanced Technologies to Reduce Design, Fabrication and Construction Costs for Future Nuclear Power Plants

    SciTech Connect

    Camillo A. DiNunzio Framatome ANP DE& S; Dr. Abhinav Gupta Assistant Professor NCSU; Dr. Michael Golay Professor MIT Dr. Vincent Luk Sandia National Laboratories; Rich Turk Westinghouse Electric Company Nuclear Systems; Charles Morrow, Sandia National Laboratories; Geum-Taek Jin, Korea Power Engineering Company Inc.

    2002-11-30

    OAK-B135 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.

  4. SERVICE PROBLEMS OF FRESH AIR FAN OF FOSSIL FUEL POWER PLANT - PART II CONSTRUCTION DESIGN IMPROVEMENT

    Microsoft Academic Search

    R. MITROVIC; M. RISTIVOJEVIC; N. STEFANOVIC; Z. STAMENIC; T. LAZOVIC

    According to improper bearing mounting on the a fresh air fan shaft in fosilfuel power plant, loss of operational reliability of immobile spherical roller bearing took place. That caused total failure of the fresh air fan installation. The consequence of this failure was a damage of the impeller with blades, and a total fracture of the shaft at the bearing

  5. Effects of plant host species and plant community richness on streptomycete community structure.

    PubMed

    Bakker, Matthew G; Bradeen, James M; Kinkel, Linda L

    2013-03-01

    We investigated soil streptomycete communities associated with four host plant species (two warm season C4 grasses: Andropogon gerardii, Schizachyrium scoparium and two legumes: Lespedeza capitata, Lupinus perennis), grown in plant communities varying in species richness. We used actinobacteria-selective PCR coupled with pyrosequencing to characterize streptomycete community composition and structure. The greatest pairwise distances between communities were observed in contrasts between monocultures of different plant species, indicating that plant species exert distinct selective effects on soil streptomycete populations. Increasing plant richness altered the composition and structure of streptomycete communities associated with each host plant species. Significant relationships between plant community characteristics, soil edaphic characteristics, and streptomycete community structure suggest that host plant effects on soil microbial communities may be mediated through changes to the soil environment. Co-occurring streptomycete taxa also shared consistent relationships with soil edaphic properties, providing further indication of the importance of habitat preference for taxon occurrence. Physical distance between sampling points had a significant influence on streptomycete community similarity. This work provides a detailed characterization of soil streptomycete populations across a field scale and in relation to plant host identity and plant community richness. PMID:23013423

  6. 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.

  7. 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 production neutralized the decreasing effect of pre-planting irrigation and two-row planting of maize on weed seed bank population. PMID:22696965

  8. Construction characteristics of pile foundation of reactor section of Kalinin nuclear power plant

    SciTech Connect

    Vorontsov, G.I.

    1987-09-01

    This article discusses the engineering geology implemented in the design and construction of the foundation for the Kalinin-1 reactor. Results of a soil analysis showed the ground to consist primarily of loams and clays from the Quaternary period and secondarily of limestone and sand. The implications of this composition for the spacing and driving of the piles are described as well as the actual mechanics encountered in driving the piles. The possibilities for future settling are examined.

  9. Ecological effects of pipeline construction through deciduous forested wetlands, Midland County, Michigan. Topical report, October 1990--August 1992

    SciTech Connect

    Rastorfer, J.R. [Chicago State Univ., IL (United States). Dept. of Biological Sciences; Van Dyke, G.D.; Zellmer, S.D.; Wilkey, P.L. [Argonne National Lab., IL (United States)

    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.

  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. PMID:23508161

  11. PC-based Simulator for Education in Advanced Nuclear Power Plant Construction

    Microsoft Academic Search

    Li-chi Cliff Po; Navajo Court

    2008-01-01

    The PC-based reactor simulation software PCTRAN was recently expanded to cover light water advanced reactors. The plant models include Generation III+ advanced PWR and BWR. The evolutionary designs are Areva EPR and GE ABWR by adding cooling path redundancy and devises for severe accident mitigation. One-step further is the passive-cooled Westinghouse AP1000 and GE ESBWR. Combined with PCTRAN's models of

  12. Nematicidal effects of cysteine proteinases against sedentary plant parasitic nematodes.

    PubMed

    Stepek, G; Curtis, R H C; Kerry, B R; Shewry, P R; Clark, S J; Lowe, A E; Duce, I R; Buttle, D J; Behnke, J M

    2007-11-01

    Cysteine proteinases from the fruit and latex of plants, such as papaya, pineapple and fig, have previously been shown to have substantial anthelmintic efficacy, in vitro and in vivo, against a range of animal parasitic nematodes. In this paper, we describe the in vitro effects of these plant extracts against 2 sedentary plant parasitic nematodes of the genera Meloidogyne and Globodera. All the plant extracts examined caused digestion of the cuticle and decreased the activity of the tested nematodes. The specific inhibitor of cysteine proteinases, E-64, blocked this activity completely, indicating that it was essentially mediated by cysteine proteinases. In vitro, plant cysteine proteinases are active against second-stage juveniles of M. incognita and M. javanica, and some cysteine proteinases also affect the second-stage juveniles of Globodera rostochiensis. It is not known yet whether these plant extracts will interfere with, or prevent invasion of, host plants. PMID:17640402

  13. 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.

  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

    2014-06-01

    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

  15. The Employment Effects of Road Construction in Rural PRELIMINARY -PLEASE DO NOT CITE WITHOUT PERMISSION

    E-print Network

    Bandyopadhyay, Antar

    in India to estimate the impact of village feeder roads on rural nonfarm economic activity. We firstThe Employment Effects of Road Construction in Rural India PRELIMINARY - PLEASE DO NOT CITE construction using the population rank of villages within districts, which dictates the order of road

  16. Improving cogeneration plant performance through effective maintenance strategies

    SciTech Connect

    Sheikh, S.M. [Fossil Consulting Services, Inc., Columbia, MD (United States)

    1998-12-31

    Gas-fired cogeneration plants supplying power and thermal energy make up an increasing percentage of new fossil generation capacity additions, both in the US and overseas. These plants are popular, not only because they cost less to build, but also because they are highly efficient and their operation and maintenance costs are lower than plants using the traditional coal-based Rankine cycle. One of the methods being used to contain the initial cost of building cogeneration plants is to minimize redundancy both in the quantity of spare equipment specified for the various systems in the plants and in the design capacity of individual components. The overall effect of such a strategy may lead to reduced reliability and availability of the cogeneration plant in the long term. Operating cogeneration plants present a variety of technologies, equipment, and operating practices. While newer cogeneration plants routinely operate at a reliability of 90% or higher, older plants may not be able to achieve such performance due to excessive equipment breakdowns or inadequate maintenance strategies. By not having the appropriate maintenance programs in place, even newer cogeneration plants are vulnerable to deteriorating reliability and availability in the long term. This paper describes mechanisms for directing maintenance resources toward reducing current maintenance costs while maintaining high availability without sacrificing long-term reliability. The maintenance strategies discussed are those that can provide the maximum benefits for improving cogeneration plant reliability, availability, capacity, cost control, and safety.

  17. 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

  18. The University of Notre Dame Effects of White-Tailed Deer (Odocoileus Virginianus) on Plants, Plant Populations and

    E-print Network

    Cochran-Stafira, D. Liane

    The University of Notre Dame Effects of White-Tailed Deer (Odocoileus Virginianus) on Plants, Plant 78712 ABSTRACT.-Largeeffects of white-tailed deer (Odocoileus virginianus) upon individual plants, plant, Indiana Vol. 146 July, 2001 No. 1 Am. Midi. Nat. 146:1-26 Effects of White-tailed Deer (Odocoileus

  19. 1 INTRODUCTION In Nuclear Power Plant (NPP) systems, effective

    E-print Network

    Paris-Sud XI, Université de

    1 INTRODUCTION In Nuclear Power Plant (NPP) systems, effective prediction methods are sought for Nuclear Power Plant Failure Scenarios Using an Ensemble-based Approach J. Liu & V. Vitelli Chair to anticipate, diag- nose and control abnormal events in a timely man- ner, and to prevent high economic losses

  20. Effects of nuclear power plants on residential property values

    Microsoft Academic Search

    Hays B. Gamble; Roger H. Downing

    1982-01-01

    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

  1. Effects of plant spinescence on large mammalian herbivores

    Microsoft Academic Search

    Susan M. Cooper; Norman Owen-Smith

    1986-01-01

    Summary Plant thorns and spines had these effects on the feeding behaviour of the three species of browsing ungulate that we studied, kudu, impala and domestic goats: (i) bite sizes were restricted, in most cases to single leaves or leaf clusters; (ii) hooked thorns retarded biting rates; (iii) the acceptability of those plant species offering small leaf size in conjunction

  2. Do soil protozoa enhance plant growth by hormonal effects?

    Microsoft Academic Search

    M. Bonkowski; F. Brandt

    2002-01-01

    We investigated changes in root morphology of watercress seedlings (Lepidium sativum L.) and effects on the composition of the rhizosphere bacterial community to test the hypothesis that rhizosphere protozoa affect plant growth by a grazing-induced stimulation of plant growth-promoting rhizobacteria. The presence of Acanthamoebae (Protozoa: Amoebida) induced changes in root morphology of watercress seedlings as soon as the root protruded

  3. PLANT GROWTH REGULATORY EFFECTS OF CHICKEN LITTER EXTRACT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chicken litter is often used in organic farming as a source of plant food, and to improve soil organic matter and microbial populations. Both positive and negative effects of such an amendment have been reported. Because of the complex interactions involving soil, plant, and microbial populations i...

  4. Browsing Effects on Wyoming Big Sagebrush Plants and Communities

    Microsoft Academic Search

    Carl L. Wambolt; Trista Hoffman

    The effect of likely yearlong browsing by several wild ungulate species on individual Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) plants and communities was studied. The investigation was conducted near Gardiner, MT, in the ungu- late-rich boundary line area of the Northern Yellowstone Winter Range. Plant level responses were measured in this study and related to reported community responses. Individual

  5. 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

  6. The Effects of Tannery Wastewater on the Development of Different Plant Species and Chromium Accumulation in Phragmites australis

    Microsoft Academic Search

    Cristina S. C. Calheiros; António O. S. S. Rangel; Paula M. L. Castro

    2008-01-01

    Toxicity tests were performed to assess the effect of tannery wastewater with different treatment levels on two wetland plants,\\u000a Phragmites australis and Typha latifolia, which are frequently used in constructed wetlands (CWs) for water treatment, and thus deepen the knowledge on their capacity\\u000a to withstand the application of industrial wastewater. Trifolium pratense, a plant generally used as an indicator in

  7. Construction of a SSR-Based Genetic Map and Identification of QTLs for Catechins Content in Tea Plant (Camellia sinensis)

    PubMed Central

    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. PMID:24676054

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. The Effects of Risk Attitude on Competitive Sucess in the Construction Industry

    E-print Network

    Kim, Hyung Jin

    2010-10-12

    This dissertation investigates the latent but critical effects of risk attitude on competitive success in construction applying an evolutionary approach. The approach considers contractors as individual entities competing with each other for common...

  13. Leadership behaviors of effective project managers in construction project organizations in Texas

    E-print Network

    Haney, Harvey Joe

    1989-01-01

    A study involving twenty-six construction firms, which practice project management in Texas, examined whether thirteen leadership behaviors could be associated with effective project managers. The data indicated that supervisors and subordinates...

  14. The effects of the implementation of grey water reuse systems on construction cost and project schedule

    E-print Network

    Kaduvinal Varghese, Jeslin

    2009-05-15

    . Implementation of a grey water reuse system has a significant effect on the capital cost of a project. The increase in cost may be attributed to dual sanitary and grey water distribution piping which doubles construction piping costs. Disinfection treatment...

  15. Integrated solar desalination/agriculture pilot plant in egypt design and construction update

    SciTech Connect

    EIDifrawi, A.; Yudow, B.

    1983-06-01

    A program to build a solar desalination pilot plant coupled with a Controlled Environment Agriculture (CEA) system in Egypt, is underway. The desalination cycle is based on three stages: two humidification processes and one dehumidification process. Updated work progress on the preliminary process flow diagrams--daytime and nighttime operations and the sensitivity analysis relative to given parameters for a base case--is presented. The base case constitutes a set of parameters representing the average conditions expected at the project site on the Red Sea at the city of Hurghada. The thermal energy requirement for the process will be supplied by solar energy. The source for electricity which is required to operate pumps and blowers is discussed. There are two options available, solar energy and wind energy.

  16. Effects of Water Pollution on Plants

    NSDL National Science Digital Library

    This is an inquiry activity that, while based on a local area (the San Francisco Bay), could be adapted to the teacher's/student's local area. Students perform an experiment in which they observe how water pollution is absorbed into plants. The site contains a teacher's guide and printable student worksheet.

  17. EFFECTS OF RAINFALL ACIDIFICATION ON PLANT PATHOGENS

    EPA Science Inventory

    Wind-blown rain, rain splash, and films of free moisture play important roles in the epidemiology of many plant diseases. The chemical nature of the aqueous microenvironment at the infection court is a potentially significant factor in the successful dissemination, establishment,...

  18. 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.…

  19. 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...

  20. Original article Effect of indole-3-acetic acid (plant auxin)

    E-print Network

    Paris-Sud XI, Université de

    Original article Effect of indole-3-acetic acid (plant auxin) on the preservation at 15 °C of boar; Effet de l'auxine végétale, l'acide 3-indole-acétique, sur la conservation du sperme de verrat pourl

  1. 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 ? 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 ?-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

  2. 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 ?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 ?-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

  3. Effect of water level fluctuation on nitrogen removal from constructed wetland mesocosms

    Microsoft Academic Search

    Chris C. Tanner; Joachim D'Eugenio; Graham B. McBride; James P. S. Sukias; Keith Thompson

    1999-01-01

    Nitrogen removal processes were investigated at three frequencies of water level fluctuation, static, low and high (0, 2 and 6 d?1), in duplicate gravel-bed constructed wetland mesocosms (0.145 m3) with and without plants (Schoenoplectus tabernaemontani). Fluctuation was achieved by temporarily pumping wastewater into a separate tank (total drain time ?35 min). Intensive sampling of the mesocosms, batch-fed weekly with ammonium-rich

  4. 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 ?g 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.

  5. 21 CFR 111.20 - What design and construction requirements apply to your physical plant?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...glass-like materials. (g) Provide effective protection against contamination of components and dietary supplements in bulk fermentation vessels, by, for example: (1) Use of protective coverings; (2) Placement in areas where you can eliminate...

  6. 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.

  7. [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. PMID:12533924

  8. 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.

  9. Gravitational effects on plant growth hormone concentration

    Microsoft Academic Search

    Robert S. Bandurski; Aga Schulze

    1983-01-01

    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

  10. Haussknechtia Elymatica: A Plant with Immunomodulatory Effects

    Microsoft Academic Search

    Zahra Amirghofran; Abbas Azadmehr; Katayoun Javidnia

    Background: Plant extracts have been widely investigated for possible immunomodu- latory properties. Objective: To study the immunomodulatory functions of the metha- nol extract of Haussknechtia elymatica (Apioideae), an herb native to south-western Iran. Methods: Delayed type hypersensitivity (DTH) skin test and measurement of an- tibody titer after immunization with Sheep-RBC was performed. (3H)-thymidine incor- poration assay on the human lymphocytes

  11. Plant pathology Effects of adjuvants on herbicidal action.

    E-print Network

    Paris-Sud XI, Université de

    Plant pathology Effects of adjuvants on herbicidal action. II. Effects of a mixture of adjuvants% in 3 days) as well as in ryegrass (less than 2.5%). The mixture greatly in- creases herbicide fertilizer no- ticeably increases herbicide penetration. Combined effects on retention and penetration lead

  12. EFFECTS OF COMPOSTED MUNICIPAL SLUDGE ON SOILBORNE PLANT PATHOGENS

    EPA Science Inventory

    The effect of composted municipal sludge (CMS) on soilborne plant pathogens was evaluated in three sets of experiments. Studies with soybeans over three growing seasons investigated the effect of CMS on root rot severity and yield in Phytophthora-infested soil, the effect of appl...

  13. The Effect of Political Unrest on Construction Time for Food Grain Warehouses in Bangladesh

    NSDL National Science Digital Library

    Choudhury, Ifte

    The purpose of this study was to examine the factors that effect actual construction time in the context of food sector projects in Bangladesh. One of the factors of particular interest is political unrest. The data for the study was obtained from a leading design and construction management company in Bangladesh. The sample size consisted of data for 104 food grain warehouse projects scattered all over the country. The effect of political unrest on construction time was analyzed in conjunction with other known variables of time overrun, such as increase in project cost and delay in procurement of construction materials. The results indicated that the effect local political unrest on construction time was statistically significant even in the presence project cost and procurement of materials variables. It was concluded that political unrest could be included in prediction models used for finding out actual construction time of food grain warehouse projects in Bangladesh. Based on these findings, a prediction model for construction time for such projects was developed.

  14. 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. PMID:24600856

  15. 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.

  16. Effect of abandonment and plant classification on carbohydrate reserves of meadow plants.

    PubMed

    Jane?ek, S; Lanta, V; Klimešová, J; Doležal, J

    2011-03-01

    We studied the effect of cessation of management on carbohydrate reserves of plants in meadows with different environmental characteristics and plant composition. We recorded storage carbohydrates and seasonal changes for 40 plant species. We asked whether there are differences in responses of carbohydrate reserves in forbs versus graminoids and in plants storing starch versus plants storing osmotically active carbohydrates. We analysed belowground organs before the meadows were mown and at the end of the vegetation season in mown versus recently abandoned plots. Whereas starch and fructans were widely distributed, raffinose family oligosaccharides were the main carbohydrate reserves of the Lamiaceae and Plantago lanceolata. Properties of carbohydrate reserves differed between forbs and graminoids but no difference was found between plants storing starch versus osmotically active carbohydrates. Graminoids had lower carbohydrate concentrations than forbs. We observed a positive effect of mowing on carbohydrate concentrations of graminoids in the dry, calcium-rich meadow and higher seasonal fluctuations of these values in the acid, wet meadow, suggesting that local factors and/or the species pool affect carbohydrate reserves. Despite local conditions, graminoids represent a distinct functional group in meadows from the point of view of their storage economy. We suggest that as well as growth, storage processes should also be considered for understanding the functioning of meadow plant communities. PMID:21309970

  17. Variation in herbivore-mediated indirect effects of an invasive plant on a native plant.

    PubMed

    Russell, F Leland; Louda, Svata M; Rand, Tatyana A; Kachman, Stephen D

    2007-02-01

    Theory predicts that damage by a shared herbivore to a secondary host plant species may either be higher or lower in the vicinity of a preferred host plant species. To evaluate the importance of ecological factors, such as host plant proximity and density, in determining the direction and strength of such herbivore-mediated indirect effects, we quantified oviposition by the exotic weevil Rhinocyllus conicus on the native wavyleaf thistle Cirsium undulatum in midgrass prairie on loam soils in the upper Great Plains, USA. Over three years (2001-2003), the number of eggs laid by R. conicus on C. undulatum always decreased significantly with distance (0-220 m) from a musk thistle (Carduus nutans L.) patch. Neither the level of R. conicus oviposition on C. undulatum nor the strength of the distance effect was predicted by local musk thistle patch density or by local C. undulatum density (<5 m). The results suggest that high R. conicus egg loads on C. undulatum near musk thistle resulted from the native thistle's co-occurrence with the coevolved preferred exotic host plant and not from the weevil's response to local host plant density. Mean egg loads on C. undulatum also were greater at sites with higher R. conicus densities. We conclude that both preferred-plant proximity and shared herbivore density strongly affected the herbivore-mediated indirect interaction, suggesting that such interactions are important pathways by which invasive exotic weeds can indirectly impact native plants. PMID:17479759

  18. 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.

  19. Design of a RCT evaluating the (cost-) effectiveness of a lifestyle intervention for male construction workers at risk for cardiovascular disease: The Health under Construction study

    Microsoft Academic Search

    Iris F Groeneveld; Karin I Proper; Allard J van der Beek; Cor van Duivenbooden; Willem van Mechelen

    2008-01-01

    BACKGROUND: Of all workers in Dutch construction industry, 20% has an elevated risk of cardiovascular disease (CVD). A major risk factor for CVD risk is an unhealthy lifestyle. The aim of our study is to design a lifestyle intervention for construction workers with an elevated CVD risk, and to evaluate its (cost-) effectiveness. METHODS\\/DESIGN: In a RCT, 692 participants will

  20. Contrasting effects of resource availability and plant mortality on plant community invasion by Bromus tectorum L

    Microsoft Academic Search

    E. Carol Adair; Ingrid C. Burke; William K. Lauenroth

    2008-01-01

    The positive effect of disturbance on plant community invasibility is one of the more consistent results in invasion ecology.\\u000a It is generally attributed to a coincident increase in available resources (due to the disturbance) that allows non-resident\\u000a plant species to establish (Davis MA, Grime JP Thompson K, J Ecol 88:528–534, 2000). However, most research addressing this\\u000a issue has been in

  1. Construction of a plant-transformation-competent BIBAC library and genome sequence analysis of polyploid Upland cotton (Gossypium hirsutum L.)

    PubMed Central

    2013-01-01

    Background Cotton, one of the world’s leading crops, is important to the world’s textile and energy industries, and is a model species for studies of plant polyploidization, cellulose biosynthesis and cell wall biogenesis. Here, we report the construction of a plant-transformation-competent binary bacterial artificial chromosome (BIBAC) library and comparative genome sequence analysis of polyploid Upland cotton (Gossypium hirsutum L.) with one of its diploid putative progenitor species, G. raimondii Ulbr. Results We constructed the cotton BIBAC library in a vector competent for high-molecular-weight DNA transformation in different plant species through either Agrobacterium or particle bombardment. The library contains 76,800 clones with an average insert size of 135 kb, providing an approximate 99% probability of obtaining at least one positive clone from the library using a single-copy probe. The quality and utility of the library were verified by identifying BIBACs containing genes important for fiber development, fiber cellulose biosynthesis, seed fatty acid metabolism, cotton-nematode interaction, and bacterial blight resistance. In order to gain an insight into the Upland cotton genome and its relationship with G. raimondii, we sequenced nearly 10,000 BIBAC ends (BESs) randomly selected from the library, generating approximately one BES for every 250 kb along the Upland cotton genome. The retroelement Gypsy/DIRS1 family predominates in the Upland cotton genome, accounting for over 77% of all transposable elements. From the BESs, we identified 1,269 simple sequence repeats (SSRs), of which 1,006 were new, thus providing additional markers for cotton genome research. Surprisingly, comparative sequence analysis showed that Upland cotton is much more diverged from G. raimondii at the genomic sequence level than expected. There seems to be no significant difference between the relationships of the Upland cotton D- and A-subgenomes with the G. raimondii genome, even though G. raimondii contains a D genome (D5). Conclusions The library represents the first BIBAC library in cotton and related species, thus providing tools useful for integrative physical mapping, large-scale genome sequencing and large-scale functional analysis of the Upland cotton genome. Comparative sequence analysis provides insights into the Upland cotton genome, and a possible mechanism underlying the divergence and evolution of polyploid Upland cotton from its diploid putative progenitor species, G. raimondii. PMID:23537070

  2. 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

  3. Temperature and wetland plant species effects on wastewater treatment and root zone oxidation.

    PubMed

    Allen, Winthrop C; Hook, Paul B; Biederman, Joel A; Stein, Otto R

    2002-01-01

    Constructed wetlands are widely used for wastewater treatment, but there is little information on processes affecting their performance in cold climates, effects of plants on seasonal performance, or plant selection for cold regions. We evaluated the effects of three plant species on seasonal removal of dissolved organic matter (OM) (measured by chemical oxygen demand and dissolved organic carbon) and root zone oxidation status (measured by redox potential [Eh] and sulfate [SO4(2-)]) in subsurface-flow wetland (SSW) microcosms. A series of 20-d incubations of simulated wastewater was conducted during a 28-mo greenhouse study at temperatures from 4 to 24 degrees C. Presence and species of plants strongly affected seasonal differences in OM removal and root zone oxidation. All plants enhanced OM removal compared with unplanted controls, but plant effects and differences among species were much greater at 4 degrees C, during dormancy, than at 24 degrees C, during the growing season. Low temperatures were associated with decreased OM removal in unplanted controls and broadleaf cattail (Typha latifolia L.) microcosms and with increased removal in beaked sedge (Carex rostrata Stokes) and hardstem bulrush [Schoenoplectus acutus (Muhl. ex Bigelow) A. & D. Löve var. acutus] microcosms. Differences in OM removal corresponded to species' apparent abilities to increase root zone oxygen supply. Sedge and bulrush significantly raised Eh values and SO4(2-) concentrations, particularly at 4 degrees C. These results add to evidence that SSWs can be effective in cold climates and suggest that plant species selection may be especially important to optimizing SSW performance in cold climates. PMID:12026068

  4. 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 ?-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.

  5. Trace gases generated in closed plant cultivation systems and their effects on plant growth.

    PubMed

    Tani, A; Kiyota, M; Aiga, I

    1995-12-01

    Interactions between plants and trace gases, especially ethylene, were investigated from two different viewpoints; ethylene is toxic for plant growth, whereas the ethylene release rate of plants can be utilized as a plant growth indicator. When lettuce plants and shiitake mushroom mycelium were cultivated in closed chambers, ethylene concentration increased with time. Ethylene was released both from lettuce plant and from shiitake mushroom mycelium. Dioctyl phthalate (DOP) and Dibutyl phthalate (DBP) were detected, and these concentrations reached 3.7 ngL-1 for DOP and 2.4 ngL-1 for DBP 4 days after closing. Organic solvents such as xylene and toluene and organic siloxane were detected with GCMS. Visible injury was observed in lettuce plants cultivated in the chambers and it seemed to result from trace contaminants such as DOP, DBP, organic solvents, dimethylsiloxane polymer, and ethylene. In order to obtain basic data of ethylene evolution from plants, ethylene concentration in a closed chamber in which the plants were cultivated under a controlled environment (25 degrees C air temperature, 60-70% relative humidity, 250-300 micromoles m-2 s-1 photosynthetic photon flux density (PPFD)) was measured. Lettuce (Lactuca sativa L. cv. Okayama) released ethylene more than Brassica rapa var. pervidis, Brassica campestris var. communis, and Brassica campestris var. narinosa. Ethylene release rate of intact lettuce plant was highly correlated with plant growth parameters such as dry weight, leaf area and photosynthetic rate. Ethylene release rates of intact lettuce plant were affected by cultivation conditions such as ambient CO2 concentration, light intensity and light/dark period. Increase in ambient ethylene level influenced lettuce growth even at the concentration of 0.1 microliter L-1. The level of ethylene inhibited leaf expansion and slightly accelerated chlorophyll degradation. It did not affect photosynthesis and transpiration, and also little affected dry matter 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

  6. The Impact of Leadership Effectiveness and Team Processes on Team Performance in Construction

    Microsoft Academic Search

    Mary Sumner; Dianne Slattery

    2010-01-01

    The ability of construction professionals to work effectively as part of interdisciplinary teams is vital as the delivery of projects moves away from the traditional design-bid-build approach. This study of 27 construction professionals participating in a leadership training institute used a competitive Request for Qualifications exercise to examine whether self-assessed leadership characteristics and satisfaction with team processes were predictive of

  7. 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...

  8. 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…

  9. 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…

  10. 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).

  11. Indirect positive effects ameliorate strong negative effects of Euphorbia esula on a native plant

    Microsoft Academic Search

    Daniel Z. AtwaterCarolyn; Carolyn M. Bauer; Ragan M. Callaway

    Invasive plant species can have strong direct negative effects on native plants. Depending on the nature of interactions among\\u000a competitors and consumers within a community, strong indirect interactions may either augment or offset direct effects. We\\u000a used path analysis to estimate the relative importance of direct and indirect effects of Euphorbia esula, an unpalatable invasive plant, on Balsamorhiza sagittata, a

  12. Effects of Heavy metals on plants and resistance mechanisms

    Microsoft Academic Search

    Shuiping Cheng

    2003-01-01

    Goal, Scope and Background  As one of the consequences of heavy metal pollution in soil, water and air, plants are contaminated by heavy metals in some\\u000a parts of China. To understand the effects of heavy metals upon plants and the resistance mechanisms, would make it possible\\u000a to use plants for cleaning and remediating heavy metal-polluted sites.\\u000a \\u000a \\u000a \\u000a Methods  The research results on the

  13. Trichoderma harzianum —interaction with plants and effect on growth response

    Microsoft Academic Search

    O. Kleifeld; I. Chet

    1992-01-01

    The fungus Trichoderma harzianum which was applied to pathogen-free soil, induced an increase in emergence of seedlings, plant height, leaf area and dry weight. The fungus was applied to the soil by three different methods: conidial suspension, wheat-bran\\/peat preparation and seed coating. The most prominent effect was observed in the wheat-bran\\/peat preparation. Responses occurred in different plant growth substrates such

  14. Plant pathology Effects of adjuvants on herbicidal action.

    E-print Network

    Paris-Sud XI, Université de

    Plant pathology Effects of adjuvants on herbicidal action. III. Effects of petroleum and rapeseed after 24 h was 20% of the applied herbicide on the adaxial surface (poorly wettable), but only 4 Résumé — Effet d'adjuvants sur l'action herbicide. III. Effets d'huiles minérale et végétale sur l

  15. 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. PMID:23579843

  16. 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 learning hypothesis, the learners who received adapted remedial explanations and revision prompts as add-ons to reduced explanations and inference prompts acquired more conceptual knowledge. PMID:25853629

  17. 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 perspectives in plant herbivore interactions and characterize the effects of growth conditions on plant and herbivore performance and their respective feedbacks. PMID:25078980

  18. Glyphosate effects on diseases of plants

    Microsoft Academic Search

    G. S. Johal; D. M. Huber

    2009-01-01

    Glyphosate, N-(phosphonomethyl)glycine, is the most extensively used herbicide in the history of agriculture. Weed management programs in glyphosate resistant (GR) field crops have provided highly effective weed control, simplified management decisions, and given cleaner harvested products. However, this relatively simple, broad-spectrum, systemic herbicide can have extensive unintended effects on nutrient efficiency and disease severity, thereby threatening its agricultural sustainability. A

  19. Heavy metal accumulation in rice plants. Effects on mineral nutrition and possible interaction of plant hormones

    SciTech Connect

    Rodrigo, M.; Martinez-Cortina, C.; Sanz, A. (Univ. of Valencia, Burjassot (Spain)); Escrig, I.; Lopez-Benet, F.J. (Univ. of Jaume I, Castello (Spain))

    1993-05-01

    As a consequence of anthropogenic activities there is a constant increase in water and soil pollution by heavy metals, which may have negative effect on plants. We have studied the effects of Cd and Ni treatments on mineral nutrition of rice plants. six days after germination. Cd (0.1 mM) or Ni (0.5 mM) was added to the nutrient solution where the plants were grown. After 10 days mineral element contents were analyzed by atomic absorption spectrophotometry after sample digestion with nitric acid (70[degrees]C 24 h) in erlenmeyer flasks. Cd-treated plants accumulated high quantities of this metal (2.28 mg/g DW, 30 fold the value found in controls), and most of it remained in the root (66% of total). A great increase in Ni contents was also observed in Ni-treated plants (3.06 mg/g DW, 28 fold higher than in controls). However, contrary to Cd, Ni accumulated preferentially in shoots (81% of total). Addition of ABA or GA[sub 3] (5 mg/l) to the nutrient solution together with the heavy metal, did not affect Cd uptake by the plants but caused a significant reduction in Ni accumulation in the shoots (60%). In both, Cd- and Ni-treated plants, the uptake of divalent cations (Ca[sup 2][sup +], Mg[sup 2][sup +]) decreased more than 50% with respect to controls. This effect was not modified by hormonal applications, though a trend to reverse the decrease in Ca[sup 2][sup +] caused by Ni was observed.

  20. 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. PMID:18214580

  1. Effects of Soil Erosion on Ecohydrology of Constructed Slopes From Opencast Coal Mining in a Mediterranean-Continental Environment.

    NASA Astrophysics Data System (ADS)

    Moreno, M.; Nicolau, J.; Espigares, T.; Merino, L.

    2007-12-01

    Numerous works have revealed strong links between hydrological processes, soil moisture, and the structure and function of biological communities. Nevertheless, the influence of soil erosion on soil-water-plant interactions has been poorly documented, particularly on constructed slopes, wherein soil erosion has a key role for restoration success. The main objective of this work is to investigate the eco-hydrological implications of soil erosion on constructed slopes from the opencast coal mining in a Mediterranean-Continental environment: the Teruel coalfield (Spain). Water deficit is the main limiting factor for revegetation success in Mediterranean-Continental environments. Soil moisture in these artificial systems is controlled by feedback mechanisms between soil erosion and vegetation. Our hypothesis states that a major effect of soil erosion on plant communities deals with the increase of the climatic water deficit. Thus, the mechanisms involved are as follows: the crust formation, the reduction of soil superficial roughness and the efficient overland flow evacuation by means of rill network. The final result is a net reduction of water availability for plants through the increase of run-off and the decrease of infiltration and re- infiltration processes at slope scale. Moreover, the lack of vegetation development leads to increase run-off and soil erosion. This work has been carried out in five constructed slopes which were reclaimed with similar treatments and substrata, but differ in vegetation cover and erosion (from 0 up to 120 t/ha/year). These differences are mainly triggered by different amounts of run-on coming from external sources as mining tracks and banks. During 2005- 06 hydrological year, we monitored run-off and sediment yield as well as soil moisture and vegetation traits (cover, biomass, water potential) on these slopes. Our results reinforce the general hypothesis. In this way, on the least eroded slopes, biological control of hydrological processes leads to maximize infiltration rates, increasing the net water availability for plant growth. On the other hand, the most eroded slopes, physically controlled by intensive run-off generation, show the lowest water availabilities, increasing the water stress borne by vegetation during the end of spring and summer.

  2. 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.

  3. The effect of raft removal and dam construction on the lower Colorado River, Texas

    E-print Network

    Hartopo

    1991-01-01

    THE EFFECT OF RAFT REMOVAL AND DAM CONSTRUCTION ON THE LOWER COLORADO RIVER, TEXAS A Thesis by HARTOPO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for degree of MASTER... OF SCIENCE May 1991 Major Subject: Geology TIIE EFFECT OI RAII' REMOVAL AND DAM CONSTRUCTION ON TI-IE LOWER COLORADO RIVER, TEXAS A Thesis by I IARTOPO Approved as to styic and content by: Christ her C. Mathewson (Chair of Committee) John R...

  4. Effect of plant populations and row spacings on plant and ear characters and grain yield of corn hybrids

    E-print Network

    Silapapun, Anek

    1976-01-01

    EFFECT OF PLANT POPULATIONS AND ROW SPACINGS ON PLANT AND EAR CHARACTERS AND GRAIN YIELD OF CORN HYBRIDS A Thesis by ANEK SILAPAPUN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE May 1976 Major Subject: Agronomy EFFECT OF PLANT POPULATIONS AND ROM SPACINGS ON PLANT AND EAR CHARACTERS AND GRAIN YIELD OF CORN HYBRIDS A Thesis by ANEK SILAPAPUN Approved as to style and content by: ( rman...

  5. 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.

  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. Plants

    NSDL National Science Digital Library

    Miss Berneski

    2011-12-10

    Get ready to explore plants! Let's Learn About Plants! Question: What do plants need to live? Watch the video to find out! What does it need to grow? Question: What are the parts of a plant? Click to find out! Parts of a Plant Question: What is the life cycle of a plant? Watch the video to find out! Plant Life Cycle Video Question: ...

  8. Effects of selenium hyperaccumulation on plant-plant interactions: evidence for elemental allelopathy?

    PubMed

    El Mehdawi, Ali F; Quinn, Colin F; Pilon-Smits, Elizabeth A H

    2011-07-01

    • Few studies have investigated plant-plant interactions involving hyperaccumulator plants. Here, we investigated the effect of selenium (Se) hyperaccumulation on neighboring plants. • Soil and litter Se concentrations were determined around the hyperaccumulators Astragalus bisulcatus and Stanleya pinnata and around the nonhyperaccumulators Medicago sativa and Helianthus pumilus. We also compared surrounding vegetative cover, species composition and Se concentration in two plant species (Artemisia ludoviciana and Symphyotrichum ericoides) growing either close to or far from Se hyperaccumulators. Then, Arabidopsis thaliana germination and growth were compared on soils collected next to the hyperaccumulators and the nonhyperaccumulators. • Soil collected around hyperaccumulators contained more Se (up to 266 mg Se kg(-1) ) than soil collected around nonhyperaccumulators. Vegetative ground cover was 10% lower around Se hyperaccumulators compared with nonhyperaccumulators. The Se concentration was higher in neighboring species A. ludoviciana and S. ericoides when growing close to, compared with far from, Se hyperaccumulators. A. thaliana showed reduced germination and growth, and higher Se accumulation, when grown on soil collected around Se hyperaccumulators compared with soil collected around nonaccumulators. • In conclusion, Se hyperaccumulators may increase the surrounding soil Se concentration (phytoenrichment). The enhanced soil Se contents around hyperaccumulators can impair the growth of Se-sensitive plant species, pointing to a possible role of Se hyperaccumulation in elemental allelopathy. PMID:21371042

  9. PLANT-ANIMAL INTERACTIONS -ORIGINAL PAPER Population density of North American elk: effects on plant

    E-print Network

    Ruess, Roger W.

    as keystone species in ecosystems they inhabit. Density- dependent processes associated with population herbivores often act as keystone species (sensu Molvar et al. 1993; Simberloff 1998) in ecosystems) of the ecosystem. We tested for indirect effects of population density of large herbivores on plant species

  10. Treatment of industrial wastewater with two-stage constructed wetlands planted with Typha latifolia and Phragmites australis.

    PubMed

    Calheiros, Cristina S C; Rangel, António O S S; Castro, Paula M L

    2009-07-01

    Industrial wastewater treatment comprises several processes to fulfill the discharge permits or to enable the reuse of wastewater. For tannery wastewater, constructed wetlands (CWs) may be an interesting treatment option. Two-stage series of horizontal subsurface flow CWs with Phragmites australis (UP series) and Typha latifolia (UT series) provided high removal of organics from tannery wastewater, up to 88% of biochemical oxygen demand (BOD(5)) (from an inlet of 420 to 1000 mg L(-1)) and 92% of chemical oxygen demand (COD) (from an inlet of 808 to 2449 mg L(-1)), and of other contaminants, such as nitrogen, operating at hydraulic retention times of 2, 5 and 7 days. No significant (P<0.05) differences in performance were found between both the series. Overall mass removals of up to 1294 kg COD ha(-1)d(-1) and 529 kg BOD(5)ha(-1)d(-1) were achieved for a loading ranging from 242 to 1925 kg COD ha(-1)d(-1) and from 126 to 900 kg BOD(5)ha(-1)d(-1). Plants were resilient to the conditions imposed, however P. australis exceeded T. latifolia in terms of propagation. PMID:19289277

  11. Construction of a recombinant Bacillus velezensis strain as an integrated control agent against plant diseases and insect pests.

    PubMed

    Roh, Jong Yul; Liu, Qin; Choi, Jae Young; Wang, Yong; Shim, Hee Jin; Xu, Hong Guang; Choi, Gyung Ja; Kim, Jin-Cheol; Je, Yeon Ho

    2009-10-01

    To construct a new recombinant strain of Bacillus velezensis that has antifungal and insecticidal activity via the expression of the insecticidal Bacillus thuringiensis crystal protein, a B. thuringiensis expression vector (pHT1K-1Ac) was generated that contained the B. thuringiensis cry1Ac gene under the control of its endogenous promoter in a minimal E. coli-B. thuringiensis shuttle vector (pHT1K). This vector was introduced into a B. velezensis isolate that showed high antifungal activities against several plant diseases, including rice blast (Magnaporthe grisea), rice sheath blight (Rhizotonia solani), tomato gray mold (Botrytis cinerea), tomato late blight (Phytophthora infestans), and wheat leaf rust (Puccinia recondita), by electroporation. The recombinant B. velezensis strain was confirmed by PCR using cry1Ac-specific primers. Additionally, the recombinant strain produced a protein approximately 130 kDa in size and parasporal inclusion bodies similar to B. thuringiensis. The in vivo antifungal activity assay demonstrated that the activity of the recombinant B. velezensis strain was maintained at the same level as that of wild-type B. velezensis. Furthermore, it exhibited high insecticidal activity against a lepidopteran pest, Plutella xylostella, although its activity was lower than that of a recombinant B. thuringiensis strain, whereas wild-type B. velezensis strain did not show any insecticidal activity. These results suggest that this recombinant B. velezensis strain can be used to control harmful insect pests and fungal diseases simultaneously in one crop. PMID:19884784

  12. 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 reported on all key decision-making process and decision quality constructs. Conclusions Evidence of PtDA effectiveness in improving the quality of the decision-making process and decision quality is strong and growing. There is not, however, consensus or standardization of measurement for either the decision-making process or decision quality. Additional work is needed to develop and evaluate measurement instruments and further explore theoretical issues to advance future research on PtDA effectiveness. PMID:24625035

  13. The composite effect of transgenic plant volatiles for acquired immunity to herbivory caused by inter-plant communications.

    PubMed

    Muroi, Atsushi; Ramadan, Abdelaziz; Nishihara, Masahiro; Yamamoto, Masaki; Ozawa, Rika; Takabayashi, Junji; Arimura, Gen-ichiro

    2011-01-01

    A blend of volatile organic compounds (VOCs) emitted from plants induced by herbivory enables the priming of defensive responses in neighboring plants. These effects may provide insights useful for pest control achieved with transgenic-plant-emitted volatiles. We therefore investigated, under both laboratory and greenhouse conditions, the priming of defense responses in plants (lima bean and corn) by exposing them to transgenic-plant-volatiles (VOCos) including (E)-?-ocimene, emitted from transgenic tobacco plants (NtOS2) that were constitutively overexpressing (E)-?-ocimene synthase. When lima bean plants that had previously been placed downwind of NtOS2 in an open-flow tunnel were infested by spider mites, they were more defensive to spider mites and more attractive to predatory mites, in comparison to the infested plants that had been placed downwind of wild-type tobacco plants. This was similarly observed when the NtOS2-downwind maize plants were infested with Mythimna separata larvae, resulting in reduced larval growth and greater attraction of parasitic wasps (Cotesia kariyai). In a greenhouse experiment, we also found that lima bean plants (VOCos-receiver plants) placed near NtOS2 were more attractive when damaged by spider mites, in comparison to the infested plants that had been placed near the wild-type plants. More intriguingly, VOCs emitted from infested VOCos-receiver plants affected their conspecific neighboring plants to prime indirect defenses in response to herbivory. Altogether, these data suggest that transgenic-plant-emitted volatiles can enhance the ability to prime indirect defenses via both plant-plant and plant-plant-plant communications. PMID:22022359

  14. The Composite Effect of Transgenic Plant Volatiles for Acquired Immunity to Herbivory Caused by Inter-Plant Communications

    PubMed Central

    Muroi, Atsushi; Ramadan, Abdelaziz; Nishihara, Masahiro; Yamamoto, Masaki; Ozawa, Rika; Takabayashi, Junji; Arimura, Gen-ichiro

    2011-01-01

    A blend of volatile organic compounds (VOCs) emitted from plants induced by herbivory enables the priming of defensive responses in neighboring plants. These effects may provide insights useful for pest control achieved with transgenic-plant-emitted volatiles. We therefore investigated, under both laboratory and greenhouse conditions, the priming of defense responses in plants (lima bean and corn) by exposing them to transgenic-plant-volatiles (VOCos) including (E)-?-ocimene, emitted from transgenic tobacco plants (NtOS2) that were constitutively overexpressing (E)-?-ocimene synthase. When lima bean plants that had previously been placed downwind of NtOS2 in an open-flow tunnel were infested by spider mites, they were more defensive to spider mites and more attractive to predatory mites, in comparison to the infested plants that had been placed downwind of wild-type tobacco plants. This was similarly observed when the NtOS2-downwind maize plants were infested with Mythimna separata larvae, resulting in reduced larval growth and greater attraction of parasitic wasps (Cotesia kariyai). In a greenhouse experiment, we also found that lima bean plants (VOCos-receiver plants) placed near NtOS2 were more attractive when damaged by spider mites, in comparison to the infested plants that had been placed near the wild-type plants. More intriguingly, VOCs emitted from infested VOCos-receiver plants affected their conspecific neighboring plants to prime indirect defenses in response to herbivory. Altogether, these data suggest that transgenic-plant-emitted volatiles can enhance the ability to prime indirect defenses via both plant-plant and plant-plant-plant communications. PMID:22022359

  15. 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.

  16. American Arachnological Society Behavioral Flexibility in Orb Web Construction: Effects of Supplies in Different Silk Glands

    E-print Network

    Bermingham, Eldredge

    in Different Silk Glands and Spider Size and Weight Author(s): William G. Eberhard Source: Journal of supplies in different silk glands and spider size and weight. J. Arachnol., 16:295-302. BEHAVIORAL FLEXIBILITY IN ORB WEB CONSTRUCTION: EFFECTS OF SUPPLIES IN DIFFERENT SILK GLANDS AND SPIDER SIZE AND WEIGHT

  17. Construction Safety Training via e-Learning: Learning Effectiveness and User Satisfaction

    ERIC Educational Resources Information Center

    Ho, Chun-Ling; Dzeng, Ren-Jye

    2010-01-01

    In Taiwan, promoting knowledge of "Labor Safety" which relates to life and work right is very important. Safety training and learning effectiveness become essential issues of adult learning. To reduce the costs of educational training, enterprises have also started to aggressively introduce e-learning education training. Unlike the construction

  18. Effects of Constructing versus Playing an Educational Game on Student Motivation and Deep Learning Strategy Use

    ERIC Educational Resources Information Center

    Vos, Nienke; van der Meijden, Henny; Denessen, Eddie

    2011-01-01

    In this study the effects of two different interactive learning tasks, in which simple games were included were described with respect to student motivation and deep strategy use. The research involved 235 students from four elementary schools in The Netherlands. One group of students (N = 128) constructed their own memory "drag and drop" game,…

  19. Effects of Glass Fabric and Laminate Construction on the Fatigue of Resin Infused Blade Materials

    E-print Network

    Effects of Glass Fabric and Laminate Construction on the Fatigue of Resin Infused Blade Materials fabrics with epoxy resins over a range of fiber contents. Significant improvements in tensile fatigue on fabric architecture and stitching details. All stitched fabric laminates show a transition to lower

  20. EFFECTIVENESS OF RADON CONTROL FEATURES IN NEW HOUSE CONSTRUCTION - SOUTH CENTRAL FLORIDA

    EPA Science Inventory

    The report gives results of a study to evaluate the effectiveness of two slab types (monolithic and slab-in-stem wall) in retarding radon entry in new homes built in accordance with the State of Florida's proposed radon standard for new construction over high radon potential soil...

  1. The Effects of Construction Probability on Word Durations during Spontaneous Incremental Sentence Production

    ERIC Educational Resources Information Center

    Kuperman, Victor; Bresnan, Joan

    2012-01-01

    In a series of seven studies, this paper examines acoustic characteristics of the spontaneous speech production of the English dative alternation ("gave the book to the boy/ the boy the book") as a function of the probability of the choice between alternating constructions. Probabilistic effects on the acoustic duration were observed in the…

  2. Transition to Work: Effects of Preparedness and Goal Construction on Employment and Depressive Symptoms

    ERIC Educational Resources Information Center

    Koivisto, Petri; Vuori, Jukka; Vinokur, Amiram D.

    2010-01-01

    This study examines the mediating role of employment preparedness in improving employment, mental health, and construction of work-life goals among young vocational school graduates who participated in the School-to-Work effectiveness trial. The trial included a 1-week intervention program that focused on enhancing employment preparedness. In this…

  3. Effect of intermittent drainage on swine wastewater treatment by marsh-pond-marsh constructed wetlands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The research objective was to investigate the effect of pulsed wastewater flow on swine wastewater treatment by marsh-pond-marsh (m-p-m) constructed wetlands. From June to October of 2004, each of four, m-p-m wetlands in Greensboro, North Carolina, USA, received a different application of swine wast...

  4. Multivariate Effect Size Estimation: Confidence Interval Construction via Latent Variable Modeling

    ERIC Educational Resources Information Center

    Raykov, Tenko; Marcoulides, George A.

    2010-01-01

    A latent variable modeling method is outlined for constructing a confidence interval (CI) of a popular multivariate effect size measure. The procedure uses the conventional multivariate analysis of variance (MANOVA) setup and is applicable with large samples. The approach provides a population range of plausible values for the proportion of…

  5. Sounds for Communication How should sounds be constructed in order to communicate information effectively? Sounds convey

    E-print Network

    Miranda, Eduardo Reck

    effectively? Sounds convey information between distal objects; they have the advantage of not requiringSounds for Communication How should sounds be constructed in order to communicate information mates. However, listeners receive a signal that combines all of the sounds present in the environment

  6. Effect of polyaluminium chloride on phosphorus removal in constructed wetlands treated with swine wastewater.

    PubMed

    Reddy, G B; Forbes, Dean A; Hunt, P G; Cyrus, Johnsely S

    2011-01-01

    Total phosphorus (TP) removal in aged constructed wetlands poses a challenge, especially when treated with swine wastewater with high concentrations of phosphorus (P). Our earlier studies with anaerobic lagoon swine wastewater treatment in constructed wetlands showed a decline in P removal (45-22%) with increased years of operation. These particular wetlands have been treated with swine wastewater every year since the first application in 1997. Preliminary lab-scale studies were conducted to evaluate the efficiency of polyaluminium chloride (PAC) in the removal of phosphate-P (PO4-P) from swine wastewater. The experimental objective was to increase the phosphorus treatment efficiency in constructed wetland by adding PAC as a precipitating agent. PAC was added by continuous injection to each wetland system at a rate of 3 L day(-1) (1:5 dilution of concentrated PAC). Swine wastewater was added from an anaerobic lagoon to four constructed wetland cells (11m wide x 40m long) at TP loads of 5.4-6.1 kg ha(-1) day(-1) in two experimental periods, September to November of 2008 and 2009. Treatment efficiency of two wetland systems: marsh-pond-marsh (M-P-M) and continuous marsh (CM) was compared. The wetlands were planted with cattails (Typha latifolia L.) and bulrushes (Scirpus americanus). In 2008, PAC treatment showed an increase of 27.5 and 40.8% of TP removal over control in M-P-M and CM respectively. Similar trend was also observed in the following year. PAC as a flocculant and precipitating agent showed potential to enhance TP removal in constructed wetlands treated with swine wastewater. PMID:22049722

  7. Inhibitory effects of Korean plants on HIV-1 activities.

    PubMed

    Min, B S; Kim, Y H; Tomiyama, M; Nakamura, N; Miyashiro, H; Otake, T; Hattori, M

    2001-09-01

    In the search for novel anti-human immunodeficiency virus type 1 (anti-HIV-1) agents from natural sources, 49 MeOH extracts of Korean plants were screened for their inhibitory effects against RNA-dependent DNA polymerase (RT) and ribonuclease H (RNase H) activities of HIV-1 reverse transcriptase and HIV-1 protease, and anti-HIV-1 activity. Regarding the HIV-1 reverse transcriptase, Agrimonia pilosa (whole plant), Cornus kousa (stem and leaf), Limonium tetragonum (root) and Mallotus japonicus (stem) showed significant inhibitory activity on RT activity with 50% inhibitory activity (IC(50)) of 8.9, 6.3, 7.5 and 11.9 microg/mL, respectively, whereas Agrimonia pilosa was also active against RNase H activity (IC(50) = 98.4 microg/mL). Four plants, namely Agrimonia pilosa (whole plant), Atractylodes japonica (root), Clematis heracleifolia (whole plant) and Syneilesis palmata (whole plant), were appreciably active (<35%) against recombinant HIV-1 protease at a concentration of 100 microg/mL. Crinum asiaticum var. japonicum (root) showed significant anti-HIV-1 activity (ED(50) = 12.5 microg/mL) with a favourable SI value of 16. PMID:11536375

  8. Simulation Modeling of the Effects of Chronic Pollutant Stress on Plant

    E-print Network

    Standiford, Richard B.

    Simulation Modeling of the Effects of Chronic Pollutant Stress on Plant Processes and Plant Community Dynamics Modeling Pollutant Uptake and Effects on the Soil-Plant-Litter System' R. J. Luxmoore2 for chemical effects on plant growth and litter decomposition. Some simulation results of a deciduous forest

  9. Effect of potassium on moringa plants growth in nutriente solution

    Microsoft Academic Search

    Lucia Helena; Ricardo Almeida Viégas; Ana Carolina; Feitosa de Vasconcelos; Hugo Vieira

    The work was carried out to evaluate the effects of K + rates on the initial growth as well as on the partition and accumulation of this element in roots, stems and leaves of moringa (Moringa oleifera Lam.) plants. A pot (0.5 dm 3) experiment was carried out under greenhouse conditions using river sand as substrate irrigated with nutrient solution

  10. Plant pathology Effects of various inhibitors including carboxin on

    E-print Network

    Paris-Sud XI, Université de

    Plant pathology Effects of various inhibitors including carboxin on Botrytis cinerea mitochondria of resistant srains, the practical control of Botrytis cinerea remains a problem. Little is known about its mitochondries de Botrytis cinerea isolées de mycé- lium. Du fait de l'apparition de phénomènes de résistance aux

  11. EFFECTS OF OZONE ON PLANTS IN THE UNITED STATES

    EPA Science Inventory

    Foliar injury to vegetation is one of the earliest and most obvious manifestations of O3 injury. However, the O3 effects are not limited to visible injury; impacts can range from reduced plant growth, decreased yield, changes in crop quality and alterations in susceptibility to a...

  12. Effects of airborne volatile organic compounds on plants

    Microsoft Academic Search

    J. N. Cape

    2003-01-01

    Routine measurements of volatile organic compounds (VOCs) in air have shown that average concentrations are very much smaller than those used in laboratory experiments designed to study the effects of VOCs on plants. However, maximum hourly concentrations of some VOCs can be 100 times larger than the average, even in rural air. Experimental studies have rarely extended for longer than

  13. Pyrrolizidine alkaloids from Canarian endemic plants and their biological effects

    Microsoft Academic Search

    Dulce M. Domínguez; Matías Reina; Arnoldo Santos-Guerra; Omar Santana; Teresa Agulló; Carmen López-Balboa; Azucena Gonzalez-Coloma

    2008-01-01

    Pyrrolizidine alkaloid (PA) producing plants belonging to the Boraginaceae (Echium wildpretti) and Asteraceae (Canariothamnus palmensis, Kleinia neriifolia, Pericallis appendiculata, Pericallis echinata, Pericallis hansenii, Pericallis multiflora, Pericallis steetzii and Senecio bollei) were selected to study their alkaloidal composition and the defensive properties (antifeedant and phytotoxic effects) of their ethanolic and alkaloidal extracts plus their isolated PAs against insects (Spodoptera littoralis, Leptinotarsa

  14. 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. PMID:25317555

  15. 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

  16. 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-term trajectories of these plant communities under different large herbivore regimes. Our results can be used to guide long-term management strategies for sagebrush systems and improve habitat for endemic wildlife species such as sage-grouse (Centrocercus spp.). PMID:25671428

  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-term trajectories of these plant communities under different large herbivore regimes. Our results can be used to guide long-term management strategies for sagebrush systems and improve habitat for endemic wildlife species such as sage-grouse (Centrocercus spp.). PMID:25671428

  18. Postural stability effects of random vibration at the feet of construction workers in simulated elevation.

    PubMed

    Simeonov, P; Hsiao, H; Powers, J; Ammons, D; Kau, T; Amendola, A

    2011-07-01

    The risk of falls from height on a construction site increases under conditions which degrade workers' postural control. At elevation, workers depend heavily on sensory information from their feet to maintain balance. The study tested two hypotheses: "sensory enhancement"--sub-sensory (undetectable) random mechanical vibrations at the plantar surface of the feet can improve worker's balance at elevation; and "sensory suppression"--supra-sensory (detectable) random mechanical vibrations can have a degrading effect on balance in the same experimental settings. Six young (age 20-35) and six aging (age 45-60) construction workers were tested while standing in standard and semi-tandem postures on instrumented gel insoles. The insoles applied sub- or supra-sensory levels of random mechanical vibrations to the feet. The tests were conducted in a surround-screen virtual reality system, which simulated a narrow plank at elevation on a construction site. Upper body kinematics was assessed with a motion-measurement system. Postural stability effects were evaluated by conventional and statistical mechanics sway measures, as well as trunk angular displacement parameters. Analysis of variance did not confirm the "sensory enhancement" hypothesis, but provided evidence for the "sensory suppression" hypothesis. The supra-sensory vibration had a destabilizing effect, which was considerably stronger in the semi-tandem posture and affected most of the sway variables. Sensory suppression associated with elevated vibration levels on a construction site may increase the danger of losing balance. Construction workers at elevation, e.g., on a beam or narrow plank might be at increased risk of fall if they can detect vibrations under their feet. To reduce the possibility of losing balance, mechanical vibration to supporting structures used as walking/working surfaces should be minimized when performing construction tasks at elevation. PMID:21071015

  19. Effects of Plant-Growth-Promoting Rhizobacteria on Yield, Growth, and Some Physiological Characteristics of Wheat and Barley Plants

    Microsoft Academic Search

    Metin Turan; Medine Gulluce; Fikrettin ?ahin

    2012-01-01

    In 2009 a greenhouse experiment was conducted to determine the effects of boron (B) and plant growth-promoting rhizobacteria (PGPR) treatments, applied either alone or in combination, on yield, plant growth, leaf total chlorophyll content, stomatal conductance, membrane leakage, and leaf relative water content of wheat (Triticum aestivum L. cv. Bezostiya) and barley (Hordeum vulgare L. cv. Tokak) plants. Results showed

  20. 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. [Westinghouse Electric Company LLC, 1000 Westinghouse Drive, Cranberry Township, PA 16066 (United States)

    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)

  1. 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

    ... 2010-07-01 true Disposal of buildings and improvements constructed under emergency...ESTATE HANDBOOK Disposal Disposal of Buildings and Other Improvements (without the Related Land) § 644.486 Disposal of buildings and improvements constructed under...

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 2011-07-01 true Disposal of buildings and improvements constructed under emergency...ESTATE HANDBOOK Disposal Disposal of Buildings and Other Improvements (without the Related Land) § 644.486 Disposal of buildings and improvements constructed under...

  3. 32 CFR 644.486 - Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 false Disposal of buildings and improvements constructed under emergency...ESTATE HANDBOOK Disposal Disposal of Buildings and Other Improvements (without the Related Land) § 644.486 Disposal of buildings and improvements constructed under...

  4. 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

    ... 2011-07-01 false Disposal of buildings and improvements constructed under emergency...ESTATE HANDBOOK Disposal Disposal of Buildings and Other Improvements (without the Related Land) § 644.486 Disposal of buildings and improvements constructed under...

  5. 32 CFR 644.486 - Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2013-07-01 true Disposal of buildings and improvements constructed under emergency...ESTATE HANDBOOK Disposal Disposal of Buildings and Other Improvements (without the Related Land) § 644.486 Disposal of buildings and improvements constructed under...

  6. Some cytological effects of systemic fungicides on fungi and plants

    Microsoft Academic Search

    D. V. Richmond; R. J. Pring

    1977-01-01

    The effects of some systemic fungicides on the fine structure of fungi and plants are described. Both benomyl and carbendazim\\u000a have an effect on dividing nuclei of Botrytis cinerea after 5 min and induce abnormalities in cell division in about 3% of\\u000a cells in the root tips of onion (Allium cepa) after 4 h. Oxycarboxin produces changes in the fine

  7. Impaired Wound Induction of 3-Deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) Synthase and Altered Stem Development in Transgenic Potato Plants Expressing a DAHP Synthase Antisense Construct.

    PubMed Central

    Jones, J. D.; Henstrand, J. M.; Handa, A. K.; Herrmann, K. M.; Weller, S. C.

    1995-01-01

    Potato (Solanum tuberosum L.) cells were transformed with an antisense DNA construct encoding part of 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase (EC 4.1.2.15), the first enzyme of the shikimate pathway, to examine the role(s) of this protein in plant growth and development. Chimeric DNA constructs contained the transcript start site, the first exon, and part of the first intron of the shkA gene in antisense or sense orientations under the control of the cauliflower mosaic virus 35S promoter. Some, but not all, of the transgenic plants expressing antisense DAHP synthase RNA showed reduced levels of wound-induced DAHP synthase enzyme activity, polypeptide, and mRNA 12 and 24 h after wounding. No alteration in the wound induction of DAHP synthase gene expression was observed in transgenic potato tubers containing the chimeric sense construct. Reduced steady-state levels of DAHP synthase mRNA were observed in stem and shoot tip tissue. Some plants with the chimeric antisense construct had reduced stem length, stem diameter, and reduced stem lignification. PMID:12228551

  8. Effects of Trampling Limitation on Coastal Dune Plant Communities

    NASA Astrophysics Data System (ADS)

    Santoro, Riccardo; Jucker, Tommaso; Prisco, Irene; Carboni, Marta; Battisti, Corrado; Acosta, Alicia T. R.

    2012-03-01

    Sandy coastlines are sensitive ecosystems where human activities can have considerable negative impacts. In particular, trampling by beach visitors is a disturbance that affects dune vegetation both at the species and community level. In this study we assess the effects of the limitation of human trampling on dune vegetation in a coastal protected area of Central Italy. We compare plant species diversity in two recently fenced sectors with that of an unfenced area (and therefore subject to human trampling) using rarefaction curves and a diversity/dominance approach during a two year study period. Our results indicate that limiting human trampling seems to be a key factor in driving changes in the plant diversity of dune systems. In 2007 the regression lines of species abundance as a function of rank showed steep slopes and high Y-intercept values in all sectors, indicating a comparable level of stress and dominance across the entire study site. On the contrary, in 2009 the regression lines of the two fenced sectors clearly diverge from that of the open sector, showing less steep slopes. This change in the slopes of the tendency lines, evidenced by the diversity/dominance diagrams and related to an increase in species diversity, suggests the recovery of plant communities in the two fences between 2007 and 2009. In general, plant communities subject to trampling tended to be poorer in species and less structured, since only dominant and tolerant plant species persisted. Furthermore, limiting trampling appears to have produced positive changes in the dune vegetation assemblage after a period of only two years. These results are encouraging for the management of coastal dune systems. They highlight how a simple and cost-effective management strategy, based on passive recovery conservation measures (i.e., fence building), can be a quick (1-2 years) and effective method for improving and safeguarding the diversity of dune plant communities.

  9. Effects of trampling limitation on coastal dune plant communities.

    PubMed

    Santoro, Riccardo; Jucker, Tommaso; Prisco, Irene; Carboni, Marta; Battisti, Corrado; Acosta, Alicia T R

    2012-03-01

    Sandy coastlines are sensitive ecosystems where human activities can have considerable negative impacts. In particular, trampling by beach visitors is a disturbance that affects dune vegetation both at the species and community level. In this study we assess the effects of the limitation of human trampling on dune vegetation in a coastal protected area of Central Italy. We compare plant species diversity in two recently fenced sectors with that of an unfenced area (and therefore subject to human trampling) using rarefaction curves and a diversity/dominance approach during a two year study period. Our results indicate that limiting human trampling seems to be a key factor in driving changes in the plant diversity of dune systems. In 2007 the regression lines of species abundance as a function of rank showed steep slopes and high Y-intercept values in all sectors, indicating a comparable level of stress and dominance across the entire study site. On the contrary, in 2009 the regression lines of the two fenced sectors clearly diverge from that of the open sector, showing less steep slopes. This change in the slopes of the tendency lines, evidenced by the diversity/dominance diagrams and related to an increase in species diversity, suggests the recovery of plant communities in the two fences between 2007 and 2009. In general, plant communities subject to trampling tended to be poorer in species and less structured, since only dominant and tolerant plant species persisted. Furthermore, limiting trampling appears to have produced positive changes in the dune vegetation assemblage after a period of only two years. These results are encouraging for the management of coastal dune systems. They highlight how a simple and cost-effective management strategy, based on passive recovery conservation measures (i.e., fence building), can be a quick (1–2 years) and effective method for improving and safeguarding the diversity of dune plant communities. PMID:22302225

  10. The effect of devitalized trabecular bone on the formation of osteochondral tissue-engineered constructs

    PubMed Central

    Lima, Eric G.; Chao, Pen-hsiu Grace; Ateshian, Gerard A.; Bal, B. Sonny; Cook, James L.; Vunjak-Novakovic, Gordana; Hung, Clark T.

    2008-01-01

    In the current study, evidence is presented demonstrating that devitalized trabecular bone has an inhibitory effect on in vitro chondral tissue development when used as a base material for the tissue-engineering of osteochondral constructs for cartilage repair. Chondrocyte-seeded agarose hydrogel constructs were cultured alone or attached to an underlying bony base in a chemically defined medium formulation that has been shown to yield engineered cartilaginous tissue with native Young's modulus (EY) and glycosaminoglycan (GAG) content. By day 42 in culture the incorporation of a bony base significantly reduced these properties (EY = 87 ± 12 kPa, GAG = 1.9 ± 0.8%ww) compared to the gel-alone group (EY = 642 ± 97 kPa, GAG = 4.6 ± 1.4%ww). Similarly, the mechanical and biochemical properties of chondrocyte-seeded agarose constructs were inhibited when co-cultured adjacent to bone (unattached), suggesting that soluble factors rather than direct cell–bone interactions mediate the chondro-inhibitory bone effects. Altering the method of bone preparation, including demineralization, or the timing of bone introduction in co-culture did not ameliorate the effects. In contrast, osteochondral constructs with native cartilage properties (EY = 730 ± 65 kPa, GAG = 5.2 ± 0.9%ww) were achieved when a porous tantalum metal base material was adopted instead of bone. This work suggests that devitalized bone may not be a suitable substrate for long-term cultivation of osteochondral grafts. PMID:18718655

  11. Effect of planting date, nitrogen rate, and plant spacing on potatoes grown for processing in Prince Edward Island

    Microsoft Academic Search

    R. P. White; J. B. Sanderson

    1983-01-01

    Russet Burbank and Kennebec potatoes were evaluated over 5 years at 3 planting dates, 3 plant spacings, and 3 nitrogen rates.\\u000a Delayed planting significantly reduced Russet Burbank yield, but did not effect Kennebec yield. Both varieties exhibited reduced\\u000a specific gravity of tubers with delayed planting. Spacings between 38 and 56 cm for Russet Burbank and 20 and 38 cm for

  12. A course in constructing effective displays of data for pharmaceutical research personnel.

    PubMed

    Bradstreet, Thomas E; Nessly, Michael L; Short, Thomas H

    2013-01-01

    Interpreting data and communicating effectively through graphs and tables are requisite skills for statisticians and non-statisticians in the pharmaceutical industry. However, the quality of visual displays of data in the medical and pharmaceutical literature and at scientific conferences is severely lacking. We describe an interactive, workshop-driven, 2-day short course that we constructed for pharmaceutical research personnel to learn these skills. The examples in the course and the workshop datasets source from our professional experiences, the scientific literature, and the mass media. During the course, the participants are exposed to and gain hands-on experience with the principles of visual and graphical perception, design, and construction of both graphic and tabular displays of quantitative and qualitative information. After completing the course, with a critical eye, the participants are able to construct, revise, critique, and interpret graphic and tabular displays according to an extensive set of guidelines. PMID:23564752

  13. [Effects of enhanced dephosphorization in the constructed wetland using water-granulated slag as matrix].

    PubMed

    Li, Hai-bo; Yang, Rui-song; Li, Xiao-dong; Sun, Tie-heng

    2009-08-15

    The phosphorus adsorption and desorption effects of water-granulated slag (WGS) were studied. A simulated vertical flow constructed wetland system was constituted using WGS as the main matrix. The influences of hydraulic residence time (HRT) and pollution load on phosphorus removal were investigated. The contributions of phosphorus removal of different horizon layers in up-flow and down-flow matrixes were studied. The results showed that WGS was a kind of adaptive desorption material for wetland due to its high saturated phosphorus adsorptive capacity (3333 mg x kg(-1)). The content of soluble calcium of WGS is 0.084%, which provides a suitable pH (7.54) for microbes and plants growth in wetland. The HRT is in positive correlation with phosphorus removal rate. The phosphorus removal rates decrease 5.9%-4.7% and 2.4%-4.7% when HRT decreases from 1 d to 0.5 d and form 2 d to 1 d, respectively. The phosphorus removal rates exceed 85% at 1 d HRT in WGS wetland. That means the optimized HRT is 1 d, and extending HRT infinitely is not helpful to phosphorus removal. The pollution load is in negative correlation with phosphorus removal rate under the conditions of steady influx concentration. The phosphorus removal rates maintain 85% when the pollution load is from 12.2 g x (m2 x d)(-1) to 36.8 g x (m2 x d)(-1). When the pollution load increases to 48.9 g x (m2 x d)(-1), the phosphorus removal rate decreases to 65% . The phosphorus removal rate exceeds 82% when the pollution load is less than 36.8 g x (m2 x d)(-1). That means higher pollution load will cause the calcium and aluminum active points of phosphorus adsorption shielded, which exist both on matrix surface and in inner pores. The range of optimized pollution load is from 24.5 g x (m2 x d)(-1) to 36.8 g x (m2 x d)(-1). The graduation mode of WGS in top layer and conventional materials in lower layer is helpful to phosphorus removal in vertical flow wetland. The phosphorus adsorptive capacities in up-flow and down-flow unit are 0.17 mg x kg(-1) and 0.05 mg x kg(-1) respectively. The WGS can be changed freely when the saturated adsorption occurs, which will extend the wetland service life. PMID:19799292

  14. Plants

    NSDL National Science Digital Library

    Miss Quinn

    2005-05-02

    Use these links to find out more about plants. This site will help you determine what a plant needs to grow. Michigan's 4-H Children's Garden This site will send you through an adventure where you try to discover if you can grow plants on the moon. Adventures of the agronauts These 2 sites are teacher resource sites on plants. Light Plants and Dark Plants, Wet Plants and Dry Ones The New York Times Daily Lesson Plan: Growing Pains ...

  15. 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-transparent, and cristae reduce. Cytochemical studies indicate that cells of plant roots exposed to WMF show the Ca2 + oversaturation both in all organelles and in a hyaloplasm of the cells unlike the control ones. The data presented suggest that prolonged plant exposures to WMF may cause different biological effects at the cellular, tissue and organ level. They may be functionally related to systems that regulate plant metabolism including the intracellular Ca 2 + homeostasis. The understanding of the fundamental mechanisms and sites of interactions between WMF and biological systems are complex and still deserve strong efforts, particular addressed to basic principles of coupling between field energy and biomolecules.

  16. 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.

  17. Interactive Effects of Nutrient and Mechanical Stresses on Plant Morphology

    PubMed Central

    Puijalon, Sara; Lena, Jean-Paul; Bornette, Gudrun

    2007-01-01

    Background and Aims Plant species frequently encounter multiple stresses under natural conditions, and the way they cope with these stresses is a major determinant of their ecological breadth. The way mechanical (e.g. wind, current) and resource stresses act simultaneously on plant morphological traits has been poorly addressed, even if both stresses often interact. This paper aims to assess whether hydraulic stress affects plant morphology in the same way at different nutrient levels. Methods An examination was made of morphological variations of an aquatic plant species growing under four hydraulic stress (flow velocity) gradients located in four habitats distributed along a nutrient gradient. Morphological traits covering plant size, dry mass allocation, organ water content and foliage architecture were measured. Key Results Significant interactive effects of flow velocity and nutrient level were observed for all morphological traits. In particular, increased flow velocity resulted in size reductions under low nutrient conditions, suggesting an adaptive response to flow stress (escape strategy). On the other hand, moderate increases in flow velocity resulted in increased size under high nutrient conditions, possibly related to an inevitable growth response to a higher nutrient supply induced by water renewal at the plant surface. For some traits (e.g. dry mass allocation), a consistent sense of variation as a result of increasing flow velocity was observed, but the amount of variation was either reduced or amplified under nutrient-rich compared with nutrient-poor conditions, depending on the traits considered. Conclusions These results suggest that, for a given species, a stress factor may result, in contrasting patterns and hence strategies, depending on a second stress factor. Such results emphasize the relevance of studies on plant responses to multiple stresses for understanding the actual ecological breadth of species. PMID:17913725

  18. 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)

  19. 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

  20. 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.

  1. 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. Figures provided are based on preliminary design. For the activities covered under this NOC, the unabated and abated TEDE to the hypothetical MEI is 1.67 E-03 and 8.34 E-01 millirem per year, respectively.

  2. 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 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. Figures provided are based on preliminary design.

  3. Effects of Invasive Alien Plants on Fire Regimes

    NSDL National Science Digital Library

    MATTHEW L. BROOKS, CARLA M. D'ANTONIO, DAVID M. RICHARDSON, JAMES B. GRACE, JON E. KEELEY, JOSEPH M. DiTOMASO, RICHARD J. HOBBS, MIKE PELLANT, and DAVID PYKE (; )

    2004-07-01

    This peer-reviewed resource from Bioscience investigates the relationship between plant invasive alien species and fire regimes. Plant invasions are widely recognized as significant threats to biodiversity conservation worldwide. One way invasions can affect native ecosystems is by changing fuel properties, which can in turn affect fire behavior and, ultimately, alter fire regime characteristics such as frequency, intensity, extent, type, and seasonality of fire. If the regime changes subsequently promote the dominance of the invaders, then an invasive plant-fire regime cycle can be established. As more ecosystem components and interactions are altered, restoration of preinvasion conditions becomes more difficult. Restoration may require managing fuel conditions, fire regimes, native plant communities, and other ecosystem properties in addition to the invaders that caused the changes in the first place. We present a multiphase model describing the interrelationships between plant invaders and fire regimes, provide a system for evaluating the relative effects of invaders and prioritizing them for control, and recommend ways to restore pre-invasion fire regime properties.

  4. Effects of DDT on the growth of crop plants.

    PubMed

    Mitra, J; Raghu, K

    1989-01-01

    The effects of DDT on the germination and growth of plants were studied using many crop species. Of the species tested, oil-rich seeds of plants, such as peanut (Arachis hypogaea) and mustard (Brassica juncea), were more prone to DDT induced inhibition of germination and subsequent plant growth than cereals, pulses and fibre crops, like rice (Oryza sativa), barley (Hordeum vulgare), mung bean Vigna radiata), pigeon pea (Cajanus cajan) and cotton (Gossypium hirsutum). Studies with (14)C labelled DDT showed that insecticide uptake by seeds was directly proportional to seed size. However, there was no direct relationship between DDT uptake by the seeds and its subsequent translocation to the growing regions or the degree of growth inhibition. Data suggest that oil content of the seeds per se has a bearing on the susceptibility or tolerance of a plant to DDT. It is suggested that lipids of the plant cell solubilize and disperse DDT in the cytoplasm, which, in turn, affects normal metabolism within the cell. PMID:15092369

  5. Effect of planting covers on herbicide persistence in landscape soils.

    PubMed

    Gan, J; Zhu, Y; Wilen, C; Pittenger, D; Crowley, D

    2003-06-15

    Recent monitoring shows that the majority of urban streams in the United States are contaminated by pesticide residues, and the contamination is mainly due to runoff from residential landscapes. In this study we evaluated the effect of landscape planting on persistence of the herbicides 2,4-D and dicamba in soil under laboratory conditions. The herbicides exhibited substantially different persistence in the same soil type that had been subjected to different planting practices for about 6 years. In the 0-10 cm surface layer, the half-life of 2,4-D was 30.7 d in soil under trees, which was about 20 times longer than in soil planted with turf grass (1.6 d). The difference in 2,4-D persistence was closely correlated to the number of 2,4-D-degrading bacteria that had evolved in the soils. The half-life of dicamba was much longer in soil under a tree canopy (149 d) than in mulched soil (7.9 d). The rate of dicamba degradation was proportional to soil organic matter content. This study indicates that planting practices can modify soil chemical properties and microbial activity and may further affect pesticide runoff potential by influencing pesticide degradation. Characterizing pesticide behavior as a function of planting covers may improve our understanding of pesticide runoff in urban environments and also help to identify strategies for minimizing pesticide contamination to urban streams. PMID:12854718

  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. PMID:22351978

  7. Differential effects of goat browsing on herbaceous plant community in a two-phase mosaic

    E-print Network

    Differential effects of goat browsing on herbaceous plant community in a two-phase mosaic O. Gabay plant communities is usually attributed to direct consumption of plants. We hypothesized that goats environmental conditions through modification of woody plant struc- ture. We assessed the effects of goats

  8. 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.

  9. Effects of Aflatoxin on Seeding Growth and Ultrastructure in Plants

    PubMed Central

    Crisan, Eli V.

    1973-01-01

    Nineteen plants belonging to 11 species of the cruciferae were studied to determine the effects of aflatoxin B1 on seed germination and seedling development. Germination was not inhibited in any test organism at a concentration of 100 ?g of aflatoxin per ml of agar substrate. Inhibition of elongation of the hypocotyls and roots in the species studied varied from 29 to 93% and from 22 to 91% in the respective tissues. Lepidium sativum was the most susceptible plant studied and exhibited the maximal inhibitory response noted above at concentrations of 8 ?g of aflatoxin per ml. The ultrastructure of Lepidium root cells treated with crystalline aflatoxin B1 exhibited morphological changes characteristic of those found in aflatoxin-treated animal cells. In addition to changes in the cytoplasmic organelles, numerous ring-shaped nucleoli with prominent nucleolar caps were produced. The effect of aflatoxin on plant cells is compared with similar effects induced by actinomycin D. Seed germination and seedling development is discussed in relation to the effects of both compounds on deoxyribonucleic acid-dependent ribonucleic acid biosynthesis. Images PMID:4767301

  10. Mutagenic effects of heavy ion radiation in plants

    NASA Astrophysics Data System (ADS)

    Mei, M.; Deng, H.; Lu, Y.; Zhuang, C.; Liu, Z.; Qiu, Q.; Qiu, Y.; Yang, T. C.

    1994-10-01

    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 occurence of white-yellow stripes on leaves of plants developed from irradiated maize seeds increased linearly with dose, and high-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. RFLP analysis of two semidwarf mutants induced by argon particles revealed that large DNA alterations might be involved in these mutants.

  11. [Construction of plant expression vectors with fusion gene of Helicobacter pylori cagA, ureB and ctb and its genetic transformation in tobacco].

    PubMed

    Cheng, Chang; Chen, Zhen; Zhu, Cheng

    2007-02-01

    Helicobacter pylori (Hp) is the principal cause of most chronic active gastric and peptic ulcer disease, and also is closely related with gastric cancer and MALT lymphoma. Current vaccines are expensive to produce and deliver, however, transgenic plants expressing recombinant vaccine immunogens offer an attractive and potential inexpensive alternative to vaccination and injection. In this study, plant expression vectors which harbor Hp related proteins CagA and UreB were constructed. Fusion gene ctb-linker-cagA and ctb-linker-ureB were cut from vectors p1300-WxCLCN and p1300-WxCLUN, and then constructed into vector pCAMBIA2301 which was under the control of the CaMV 35S promoter by series molecular methods. Those reconstructed vectors were named p2301-35SCLCN and p2301-35SCLUN and were introduced into Agrobacterium tumefaciens strain EHA105 .Tobacco was transformed by co-cultivating leaf discs with Agrobacterium strains harboring fusion genes. The regenerated Kanamycin-resistant transforms were selected, elongated, rooted and transferred fdr flowering in greenhouse. Recombinant plant expression vectors were confirmed by digestion and PCR and transgenic plants were analyzed by PCR, GUS histochemical assays, PCR-Southern blot. The results show that more than 80% transgenic plants are confirmed to be positive ones and these results also indicate that ctb-linker-cagA and ctb-linker-ureB are integrated into the genomic DNA of the tobacco which laid a solid foundation for the research of establishing transgenic plants as bioreactors to carry microbe antigen and Hp transgenic plant vaccines. PMID:17436619

  12. Construction and application of a mass spectral and retention time index database generated from plant GC\\/EI-TOF-MS metabolite profiles

    Microsoft Academic Search

    Cornelia Wagner; Michael Sefkow; Joachim Kopka

    2003-01-01

    The non-supervised construction of a mass spectral and retention time index data base (MS\\/RI library) from a set of plant metabolic profiles covering major organs of potato (Solanum tuberosum), tobacco (Nicotiana tabaccum), and Arabidopsis thaliana, was demonstrated. Typically 300–500 mass spectral components with a signal to noise ratio ?75 were obtained from GC\\/EI-time-of-flight (TOF)-MS metabolite profiles of methoxyaminated and trimethylsilylated

  13. Effect of intermittent drainage on swine wastewater treatment by marsh–pond–marsh constructed wetlands

    Microsoft Academic Search

    M. E. Poach; P. G. Hunt; G. B. Reddy; K. C. Stone; M. H. Johnson; A. Grubbs

    2007-01-01

    The research objective was to investigate the effect of intermittent wetland drainage on swine wastewater treatment by marsh–pond–marsh (m–p–m) constructed wetlands. For 16 weeks beginning in June 2002, each of four m–p–m wetlands in Greensboro, NC, USA, received a different application of swine wastewater. The four application schemes were as follows: (1) continuous application; (2) 1 week of no application

  14. Effects of gravity on temporary spiral construction by Leucauge mariana (Araneae: Araneidae)

    Microsoft Academic Search

    William G. Eberhard; Smithsonian Tropical

    1987-01-01

    Temporary spirals (TSP) in non-horizontal webs ofLeucauge mariana (Key-serling) showed consistent up-down asymmetries in initiation sites and spacing between loops that were not present in\\u000a horizontal webs, even when possible effects of other web asymmetries were controlled for by changing the web's orientation\\u000a just as TSP construction began. Cues from the web itself also affect spacing, since patterns of TSP

  15. Genomic clones of bovine parvovirus: Construction and effect of deletions and terminal sequence inversions on infectivity

    Microsoft Academic Search

    B. C. Shull; K. C. Chen; M. Lederman; E. R. Stout; R. C. Bates

    1988-01-01

    Genomic clones of the autonomous parvovirus bovine parvovirus (BPV) were constructed by blunt-end ligation of reannealed virion plus and minus DNA strands into the plasmid pUC8. These clones were stable during propagation in Escherichia coli JM107. All clones tested were found to be infectious by the criteria of plaque titer and progressive cytophathic effect after transfection into bovine fetal lung

  16. 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. PMID:25791450

  17. Effects of vegetation on surface stability and hydrology of a prototype barrier constructed over nuclear wastes

    SciTech Connect

    Link, S.O.; Ward, A.L.; Walters, W.H. [Pacific Northwest Lab., Richland, WA (United States)] [and others

    1995-06-01

    Earthen barriers are being developed to prevent water from entering nuclear wastes at the Hanford Site in south-central Washington. We constructed a prototype barrier (2700 m{sup 2}) and are conducting a test to determine if it can prevent water from draining at 3 times normal precipitation. Plants will function to minimize erosion and maximize the loss of water from the surface soils. The experiment was initiated in the October 1994. The surface was revegetated with seedlings of Artemisia tridentata and Chrysothamnus nauseosus (2 shrubs m{sup -2}) and seeded with native perennial grasses. Initial soil water observations indicate more water near the surface and considerable spatial variability. The revegetation effort reduced wind erosion.

  18. Construction engineering of steel tub-girder bridge systems for skew effects

    NASA Astrophysics Data System (ADS)

    Jimenez Chong, Juan Manuel

    Closed structural sections, such as those having circular, rectangular or trapezoidal shape, possess high rotational rigidity when compared to open sections such as I-girders. The high torsional rigidity of closed sections makes them ideal for use in highly curved bridges. In this case, the geometry of the bridge results in large torsional forces. Because of structural efficiency and economy reasons, most of these closed-section bridges consist of a trapezoidal cross-section, with a top concrete slab and bottom and side steel plates. The slab is cast after the steel is erected and thus a system of internal diaphragms and braces is necessary to stabilize the system during erection. During the steel erection and the early stages of the concrete deck placement, the section can be considered as quasi-closed as the top concrete flange has not been cast or is not yet effective. During steel erection, undetermined and/or large torsional forces and/or displacements may result in fit-up problems requiring large stresses to overcome. During concrete deck placement, the undetermined displacements can affect the control of the deck thickness and the final deck geometry, such as the alignment of deck joints and the matching of stages in phased constructions projects. Due to the interactions between their various components, the behavior of curved and skewed tub-girder bridges is significantly more complex than that of straight bridges. When skewed supports are used in tub-girders, the interaction of the girder bending rotations and the displacement constraints induced by the skewed support diaphragms causes twisting of the girders at the supports. These twist rotations introduce additional torques into the system. Both curvature and skew can cause design and construction difficulties, especially at the supports, where the corresponding steel dead load deflections and the large torsional stiffness of the girders may lead to large fit-up forces. Currently, the general understanding of the level of sophistication of analysis models required to properly predict forces and deformations of curved and/or skewed bridges during construction is limited. The development of guidelines regarding the sufficiency of simplified methods of structural analysis is the overall motivation and objective of this dissertation. This research addresses the construction load effects due to skew and due to combined skew and curvature and develops design recommendations and analytical tools for the construction engineering of tub-girder bridges. The effects of skew and curvature are studied by examining the results for different levels of analysis for 18 representative bridges. These bridges reflect the range of bridge curvature and skew used in current practice. By comparing the output from simplified analysis methods to validated refined 3D FEA solutions, general conclusions are developed as to when the simplified methods provide sufficient results. An important original contribution of this research is that the data generated constitutes the first systematic study on a large set of curved and skewed tub-girder bridges using consistent refined 3D FEA models to model construction forces and deformations. As such, the results of this research can serve as a benchmark for current and future improvements in methods of analysis and design for the construction engineering of curved and skewed tub-girder bridges. In the current research, this data has been used in both straight and curved tub-girder bridges to: • Develop a simplified 1D analysis method to account for the effect of skew on girder twist rotations and internal torques, • Evaluate the effect of skew on component forces, and propose improved simplified procedures to capture these effects, • Identify interactions between components and develop improved simplified analysis methods to account for these effects, • Establish limits for when the improved 1D and 2D simplified methods of analysis are sufficient for construction engineering analysis, and • Identify sources of steel erection fit-up proble

  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. The antinociceptive effect of some Egyptian medicinal plant extracts

    Microsoft Academic Search

    A. H. Atta; K. Abo EL-Sooud

    2004-01-01

    The antinociceptive effect of methanolic extracts (200 and 400mgkg?1) of eight Egyptian medicinal plants was studied using acetic acid-induced writhing and tail-flick test in mice. Oral administration of 400mgkg?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

  1. Effects of sparsely and densely ionizing radiation on plants

    Microsoft Academic Search

    Veronica De Micco; Carmen Arena; Diana Pignalosa; Marco Durante

    2011-01-01

    One of the main purposes leading botanists to investigate the effects of ionizing radiations is to understand plant behaviour\\u000a in space, where vegetal systems play an important role for nourishment, psychological support and functioning of life support\\u000a systems. Ground-based experiments have been performed with particles of different charge and energy. Samples exposed to X-\\u000a or ?-rays are often used as

  2. 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.

  3. Functional and effective hippocampal-neocortical connectivity during construction and elaboration of autobiographical memory retrieval.

    PubMed

    McCormick, Cornelia; St-Laurent, Marie; Ty, Ambrose; Valiante, Taufik A; McAndrews, Mary Pat

    2015-05-01

    Autobiographical memory (AM) provides the opportunity to study interactions among brain areas that support the search for a specific episodic memory (construction), and the later experience of mentally reliving it (elaboration). While the hippocampus supports both construction and elaboration, it is unclear how hippocampal-neocortical connectivity differs between these stages, and how this connectivity involves the anterior and posterior segments of the hippocampus, as these have been considered to support the retrieval of general concepts and recollection processes, respectively. We acquired fMRI data in 18 healthy participants during an AM retrieval task in which participants were asked to access a specific AM (construction) and then to recollect it by recovering as many episodic details as possible (elaboration). Using multivariate analytic techniques, we examined changes in functional and effective connectivity of hippocampal-neocortical interactions during these phases of AM retrieval. We found that the left anterior hippocampus interacted with frontal areas during construction and bilateral posterior hippocampi with visual perceptual areas during elaboration, indicating key roles for both hippocampi in coordinating transient neocortical networks at both AM stages. Our findings demonstrate the importance of direct interrogation of hippocampal-neocortical interactions to better illuminate the neural dynamics underlying complex cognitive tasks such as AM retrieval. PMID:24275829

  4. Selective effect of pesticides on plant - a review.

    PubMed

    Parween, Talat; Jan, Sumira; Mahmooduzzafar; Fatma, Tasneem; Siddiqui, Zahid Hameed

    2014-09-12

    ABSTRACT 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

  5. Development and application of dynamic air chambers for measurement of volatilization fluxes of benzene and MTBE from constructed wetlands planted with common reed.

    PubMed

    Reiche, Nils; Lorenz, Wilhelm; Borsdorf, Helko

    2010-03-01

    Phytoremediation of industrially contaminated groundwater has been a proven technique for several decades. However, mass balances of contaminants are often focused in laboratory investigations. The evaluation of the transfer of volatile organic compounds (VOCs) under field conditions from the saturated and vadose soil zone into the atmosphere, directly or via plants, is rarely part of the research scope. This can provoke problems--particularly with regard to legal issues--if large-scale phytoremediation sites are situated near residential areas. In this study volatilization of VOCs was quantified in a horizontal-flow constructed wetland planted with reed grass. For this purpose, a specially designed air chamber was constructed, validated, and routine sampling campaigns were performed over the course of one year. Results indicate that the overall volatilization of the observed contaminants benzene and methyl tert-butyl ether (MTBE) depended on seasonal variations with the highest volatilization fluxes measured in summer, when the detected volatilization fluxes of 846+/-116 and 252+/-11 microg m(-2) h(-1) for MTBE and benzene, respectively, accounted for 2.4% and 5.6% of the respective overall contaminant mass loss in the planted wetland. Furthermore, chamber data give strong evidence for the increased volatilization of VOCs through vegetation by direct comparison of planted and unplanted wetlands. PMID:20132961

  6. Biological effects due to weak magnetic field on plants

    NASA Astrophysics Data System (ADS)

    Belyavskaya, N. A.

    2004-01-01

    Throughout the evolution process, Earth's magnetic field (MF, about 50 ?T) was a natural component of the environment for living organisms. Biological objects, flying on planned long-term interplanetary missions, would experience much weaker magnetic fields, since galactic MF is known to be 0.1-1 nT. However, the role of weak magnetic fields and their influence on functioning of biological organisms are still insufficiently understood, and is actively studied. Numerous experiments with seedlings of different plant species placed in weak magnetic field have shown that the growth of their primary roots is inhibited during early germination stages in comparison with control. The proliferative activity and cell reproduction in meristem of plant roots are reduced in weak magnetic field. Cell reproductive cycle slows down due to the expansion of G 1 phase in many plant species (and of G 2 phase in flax and lentil roots), while other phases of cell cycle remain relatively stabile. In plant cells exposed to weak magnetic field, the functional activity of genome at early pre-replicate period is shown to decrease. Weak magnetic field causes intensification of protein synthesis and disintegration in plant roots. At ultrastructural level, 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 were observed in pea roots exposed to weak magnetic field. Mitochondria were found to be very sensitive to weak magnetic field: their size and relative volume in cells increase, matrix becomes electron-transparent, and cristae reduce. Cytochemical studies indicate that cells of plant roots exposed to weak magnetic field show Ca 2+ over-saturation in all organelles and in cytoplasm unlike the control ones. The data presented suggest that prolonged exposures of plants to weak 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.

  7. Effects of elevated CO{sub 2} on stem maintenance and construction respiration in Pinus ponderosa

    SciTech Connect

    Carey, E.V.; Delucia, E.H.; Ball, J.T. [Univ. of Illinois, Urbana, IL (United States)]|[Desert Research Institute, Reno, NV (United States)

    1995-06-01

    We measured woody tissue respiration on stems of 4-year-old Pinus ponderosa growing under ambient (350 ppm) and twice ambient (700 ppm) atmospheric CO{sub 2} in open top chambers located at the Institute of Forest Genetics in Placerville, CA. Mean daily respiration rate per unit volume of wood was greater in trees growing under the elevated (700 ppm) treatment (46.75 vs 40.45 mol m{sup -3} d{sup -1}). This difference was due to a higher Q{sub 10} of respiration in the elevated (Q{sub 10}=2.20) versus the ambient (Q{sub 10}=1.67) treatment. The higher Q{sub 10} and CO{sub 2} efflux rate were not due to differences in phenology but may reflect a difference in demand for metabolic energy. In contrast to results seen in leaves growing under elevated atmospheric CO{sub 2} analysis of tissue construction costs suggests no difference in wood composition between treatments. Estimates of growth respiration calculated from construction costs also did not differ. Under future predicted atmospheric conditions, changes in the maintenance respiration of woody tissue may lead to an increase in the respiration component of whole plant carbon budgets of Pinus ponderosa.

  8. 76 FR 65753 - Monitoring the Effectiveness of Maintenance at Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-24

    ...Effectiveness of Maintenance at Nuclear Power Plants,'' which provides methods that...Effectiveness of Maintenance at Nuclear Power Plants,'' of Title 10 of the Code of...inclusion in guides currently being developed or improvements in all...

  9. 76 FR 55137 - Monitoring the Effectiveness of Maintenance at Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-06

    ...Effectiveness of Maintenance at Nuclear Power Plants,'' which provides methods that...Effectiveness of Maintenance at Nuclear Power Plants,'' of Title 10, of the Code...inclusion in guides currently being developed or improvements in all...

  10. 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.

  11. [Effects of soil compactness on ginger plant senescence].

    PubMed

    Shang, Qing-wen; Kong, Xiang-bo; Wang, Yu-xia; Xu, Kun

    2008-04-01

    Based on the determinations of main physiological parameters of ginger plant grown in different compactness soils, this paper studied the effects of soil compactness on the senescence of ginger plant. The results showed that with the increase of soil compactness, the root activity and the leaf NRase activity, chlorophyll content and photosynthetic rate of ginger plant declined, while the leaf electrolytic leakage and MDA content increased. The activities of leaf SOD, POD and CAT decreased with increasing soil compactness at early growth stage but were in adverse at late growth stage. At vigorous growth stage, the root activity and the leaf chlorophyll content and photosynthetic rate in the soil with a compactness of 1.49 g cm(-3) were 30.9%, 19.0% and 17.9% lower, and the leaf electrolytic leakage and MDA content were 57.2% and 26.3% higher, respectively, compared with those in the soil with a compactness of 1.20 g cm(-3), which indicated that compacted soil could accelerate the senescence of ginger plant. PMID:18593038

  12. Effects of Hypoxia on Animal Burrow Construction and Consequent Effects on Sediment Redox Profiles

    EPA Science Inventory

    Previous studies investigating the effects of hypoxia on benthic infauna and consequent effects on sediment chemistry provide only correlative results from the field. In order to establish causation and isolate effects of hypoxia on individual species, we conducted a laboratory ...

  13. Municipal solid-waste composting: Technologies, health effects, effects on plant growth and yield, regulations, and descriptions of U. S. sites

    SciTech Connect

    Curtis, C.C.; Brenniman, G.R.; Hallenbeck, W.H.

    1991-06-01

    As stated in the Illinois Solid Waste Management Act, composting is considered to be an acceptable alternative to landfilling. There are nine operational municipal solid waste (MSW) composting facilities and one pilot program reviewed in the report. Other facilities in operation or under construction in the U.S. are summarized in the Appendix. The report also discusses the following topics: composting technology, potential effects of MSW compost on human health and plant growth and yield, and regulations.

  14. Impact of Public Policy and Societal Risk Perception on U.S. Civilian Nuclear Power Plant Construction

    E-print Network

    Ford, David N.

    Impact of Public Policy and Societal Risk Perception on U.S. Civilian Nuclear Power Plant permit applications for 26 new nuclear power reactors. However, the previous generation of U.S. civilian of nuclear plants. Results point to the critical role societal perceptions of nuclear power risk play

  15. Effects of glycoalkaloids from Solanum plants on cucumber root growth.

    PubMed

    Sun, Fang; Li, Shengyu; He, Dajun; Cao, Gang; Ni, Xiuzhen; Tai, Guihua; Zhou, Yifa; Wang, Deli

    2010-09-01

    The phytotoxic effect of four glycoalkaloids and two 6-O-sulfated glycoalkaloid derivatives were evaluated by testing their inhibition of cucumber root growth. The bioassays were performed using both compounds singly and in equimolar mixtures, respectively. Cucumber root growth was reduced by chaconine (C), solanine (S), solamargine (SM) and solasonine (SS) with IC(50) values of 260 (C), 380 (S), 530 (SM), and 610 microM (SS). The inhibitory effect was concentration-dependent. 6-O-sulfated chaconine and 6-O-sulfated solamargine had no inhibitory effects, which indicated that the carbohydrate moieties play an important role in inhibiting cucumber root growth. The equimolar mixtures of paired glycoalkaloids, both chaconine/solanine and solamargine/solasonine, produced synergistic effects on inhibition of cucumber root growth. By contrast, mixtures of unpaired glycoalkaloids from different plants had no obviously synergistic effects. The growth inhibited plant roots lacked hairs, which implied that inhibition was perhaps at the level of root hair growth. PMID:20591452

  16. 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.

  17. Effective field theory and projective construction for Z{sub k} parafermion fractional quantum Hall states

    SciTech Connect

    Barkeshli, Maissam; Wen Xiaogang [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2010-04-15

    The projective construction is a powerful approach to deriving the bulk and edge field theories of non-Abelian fractional quantum Hall (FQH) states and yields an understanding of non-Abelian FQH states in terms of the simpler integer quantum Hall states. Here we show how to apply the projective construction to the Z{sub k} parafermion (Laughlin/Moore-Read/Read-Rezayi) FQH states, which occur at filling fraction nu=k/(kM+2). This allows us to derive the bulk low-energy effective field theory for these topological phases, which is found to be a Chern-Simons theory at level 1 with a U(M)xSp(2k) gauge field. This approach also helps us understand the non-Abelian quasiholes in terms of holes of the integer quantum Hall states.

  18. Allelopathic effects of ragweed (Ambrosia artemisiifolia L.) on cultivated plants.

    PubMed

    Lehoczky, E; Gólya, G; Szabó, R; Szalai, A

    2011-01-01

    During the past years ragweed has been coming to the forefront of interest in Hungary and in other European countries as well because its serious health risk. Results of the 5th National Weed Survey has proven that ragweed is the most important weed species on Hungarian field lands, its coverage shows a rising tendency in cereals moreover it not only occurs in cultivated plants. Allelopathic effects of aqueous extracts derived from different parts of ragweed plants (air dried leafy stems, seeds) on the germination and growth of other cultivated plants [maize (Zea mays L.), winter wheat (Triticum aestivum L.), rye (Secale cereale L.), oat (Avena sativa L.)] were studied. The extracts made for the trials were prepared with distilled water. Petri dishes were used for the germination experiments and distilled water was used as a control treatment. The seven days long experiment was carried out within a Binder-type thermostat under dark conditions. The germination percentage was checked in every two days and the growth of sprouts was evaluated after a week counting the germinated seeds and measuring the length of the radicle and plumule. The measured data were statistically analysed and the effect of extracts on germinating and length of sprouts were assessed. PMID:22696964

  19. Study of the refirming effect of a plant complex.

    PubMed

    Benaiges, A; Marcet, P; Armengol, R; Betes, C; Gironés, E

    1998-08-01

    Loss of skin elasticity is one of the main problems of ageing. This is a mechanical property influenced by elastin, a protein in the dermis which, together with collagen and glycosaminoglycans, makes up the connective tissue. This tissue is affected by a large number of events (such as cutaneous ageing, pregnancy, slimming processes and cellulitis) which eventually cause it to change. At the same time, the metabolism of the proteins of the connective tissue decreases and there is an ever greater presence of enzymes, principally elastases and collagenases, which are responsible for breaking down the elastin and the collagen. One way to prevent such a loss of elasticity is to use active ingredients that are able to inhibit elastase enzymes. A plant complex was prepared using the following plants: lady's thistle (Silybum marianum GAERTN), alchemilla or yarrow (Alchemilla vulgaris L.), horsetail (Equisetum arvense L.) as well as germinated seeds (Glycine soja Siebold and Zucc., Triticum vulgare Vilars, Medicago sativa L., Raphanus sativus L.). The complex was standardized to give the corresponding active principles, silybin, tannins, silicon and peptides, respectively, and in vitro enzymatic tests were carried out to establish its ability to inhibit elastase. The study of enzymatic inhibition was carried out using two enzymes: (1) porcine pancreatic elastase (PPE), and (2) human leukocyte elastase (HLE). The results showed that the plant complex presents non-competitive inhibition in the order of 41.0% against PPE and 50.0% against HLE. An in vivo test was made alongside the in vitro test using an SEM 474 Cutometer (Courage & Khazaka) to study the elasticity of the skin, and positive effects were obtained when applying a cosmetic formulation containing 5% of the plant complex. Image analysis of duplicates of the cutaneous surface, before and after treatment began with a product containing 5% of plant complex and showed that wrinkles were decreased by 36.7%. PMID:18505506

  20. Effects of the plant growth regulator, chlormequat, on mammalian fertility.

    PubMed

    Sørensen, Martin T; Danielsen, Viggo

    2006-02-01

    This paper summarizes the consequences of exposure to chlormequat, a plant growth regulator, on reproduction in mammals. Plant growth regulators are chemicals used to manipulate plant growth, flowering and fruit yield. In grain crops, plant growth regulators are applied to promote sturdier growth and reduce the risk of lodging. Chlormequat is the most common plant growth regulator. Maximum residue limits of chlormequat in food products are 10 mg/kg in oat and pear, 3 mg/kg in wheat and rye, and 0.5 mg/kg in milk. In Denmark, results from experiments with pigs in the late 1980s showed sows that display impaired reproduction, mainly impaired oestrus, when fed grain from crop treated with chlormequat. Subsequently, the advisory body to the Danish pig industry recommended limiting the use of grain (maximum 30% of diet energy) from crop treated with chlormequat given to breeding stock due to the risk of reproduction problems. More recently, experiments have been conducted to evaluate the influence of chlormequat-treated wheat crop on reproductive function in male and female mice. These experiments showed that epididymal spermatozoa from mice on feed or water containing chlormequat had compromised fertilizing competence in vitro, while reproduction in female mice was not compromised. The estimated intake of chlormequat in the pig (0.0023 mg/kg bw/day) and the mouse (0.024 mg/kg bw/day) experiments was below the acceptable daily intake of 0.05 mg/kg bw/day. Reports from the industry do not show any effects at these low levels. PMID:16466532

  1. 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 mineralization or food web stability. Hence, the composition and structure of entire soil food webs vary at the scale of individual plants and are strongly influenced by the species identity of the plant. However, the ecosystem functions these food webs provide are determined by the identity of the entire plant community. PMID:21058562

  2. 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.

  3. 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 from herbaceous neighbors and less on the extent that CO{sub 2} enhances Achnatherum growth during periods of severe drought.

  4. Reduced Position Effect in Mature Transgenic Plants Conferred by the Chicken Lysozyme Matrix-Associated Region

    Microsoft Academic Search

    Paul Keizer; Ritsert C. Jansen; Jos Heldens; Annelies Loonen; ?udmila Mlynárová; Willem J. Stiekema; Jan-Peter Nap

    1994-01-01

    Matrix-associated regions may be useful for studying the role of chromatin architecture in transgene activity of transformed plants. The chicken lysozyme A element was shown to have specific affinity for tobacco nuclear matrices, and its influence on the variability of transgene expression in tobacco plants was studied. T-DNA constructs in which this element flanked either the ?-glucuronidase (GUS) reporter gene

  5. 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.

  6. Effects of invasive species on plant communities: an example using submersed aquatic plants at the regional scale

    Microsoft Academic Search

    Maria J. SantosLars; Lars W. Anderson; Susan L. Ustin

    2011-01-01

    Submersed aquatic plants have a key role in maintaining functioning aquatic ecosystems through their effects on the hydrological\\u000a regime, sedimentation, nutrient cycling and habitat of associated fauna. Modifications of aquatic plant communities, for example\\u000a through the introduction of invasive species, can alter these functions. In the Sacramento-San Joaquin River Delta, California,\\u000a a major invasive submersed plant, Brazilian waterweed Egeria densa,

  7. Collaborative encoding and memory accuracy: examining the effects of interactive components of co-construction processes.

    PubMed

    Foley, Mary Ann; Fried, Adina Rachel; Cowan, Emily; Bays, Rebecca Brooke

    2014-01-01

    In 2 experiments, the effect of collaborative encoding on memory was examined by testing 2 interactive components of co-construction processes. One component focused on the nature of the interactive exchange between collaborators: As the partners worked together to create descriptions about ways to interact with familiar objects, constraints were imposed on the interactions by requiring them to take turns (Experiment 1) or to interact without constraints (Experiment 2). The nature of the relationship between partners was manipulated as well by including 2 pair types, friends or unfamiliar peers (Experiments 1 and 2). Interactive component effects were found to influence spontaneous activations through content analyses of participants' descriptions, the patterns of false recognition errors, and the relationship between content and errors. The findings highlight the value of examining the content of participants' collaborative efforts when assessing the effects of collaborative encoding on memory and point to mechanisms mediating collaboration's effects. Because the interactions occurred within the context of an imagery generation task, the findings are also intriguing because of their implications for the use of guided imagery techniques that incorporate co-construction processes. PMID:24016139

  8. Effect of cold and menthol on membrane potential in plants.

    PubMed

    Kupisz, Kamila; Trebacz, Kazimierz

    2011-04-01

    In animals, cooling substances such as menthol are perceived as cold sensation because they bind to the same receptor TRPM8 (transient receptor potential melastatin) that activates upon temperature drops. We investigated the effect of menthol on the plant membrane potential to search for analogies between animal and plant perception systems. The study was conducted on the liverwort Conocephalum conicum- a non-vascular plant generating action potentials (APs) in response to different stimuli including cold. (+)Menthol, (-)menthol and (+/-)menthol induced one or more APs, depending on the concentration. In contrast to animal reactions to menthol, threshold concentrations of these isomers were the same (1 mM). The presence of menthol in medium shortened cold-induced APs, whereas low temperature prolonged the repolarization phase of AP evoked by menthol. Cells of C. conicum with anion and potassium channels blocked by anthracene-9-carboxylic acid (A9C) and tetraethylammonium chloride (TEACl) generate short spike-like voltage transients (VTs) in response to cold and light stimulation. Membrane potential changes evoked by menthol in A9C- and TEACl-treated plants differed significantly from VTs - lasted much longer and frequently occurred in series. 5 mM LaCl(3) , 1 mM EGTA (ethylene glycol-bis(2-aminoethyl ether)-N,N,N',N'-tetraacetic acid) (0 Ca(2+) ) but not 0.2 mM verapamil blocked the putative calcium component of AP induced by menthol. Similar inhibitory effect was observed after the application of proton pump inhibitors: 0.05 mM N,N-dicyclohexylcarbodiimide (DCCD), 0.05 mM diethylstilbestrol (DES) or 0.01 mM carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP). Our results indicate that cold and menthol act independently, activating different membrane transporters in C. conicum cells. PMID:21214882

  9. Effects of virus on plant fecundity and population dynamics.

    PubMed

    Prendeville, Holly R; Tenhumberg, Brigitte; Pilson, Diana

    2014-06-01

    Microorganisms are ubiquitous and thought to regulate host populations. Although microorganisms can be pathogenic and affect components of fitness, few studies have examined their effects on wild plant populations. As individual traits might not contribute equally to changes in population growth rate, it is essential to examine the entire life cycle to determine how microorganisms affect host population dynamics. In this study, we used data from common garden experiments with plants from three Cucurbita pepo populations exposed to three virus treatments. These data were used to parameterize a deterministic matrix model, which allowed us to estimate the effect of virus on components of fitness and population growth rate. Virus did not reduce fruit number, but population growth rates varied among virus treatments and wild C. pepo populations. The effect of virus on population growth rate depended on virus species and wild C. pepo population. Contributions of life-history transitions and life-history traits to population growth rates varied among populations and virus treatments. However, this population-virus interaction was not evident when examining individual components of fitness. Thus, caution must be used when interpreting the effects of changes in individual traits, as single traits do not always predict population-level change accurately. PMID:24571200

  10. Wetland assessment of the effects of construction and operation of a depleteduranium hexafluoride conversion facility at the Portsmouth, Ohio, site.

    SciTech Connect

    Van Lonkhuyzen, R.

    2005-09-09

    The U.S. Department of Energy (DOE) Depleted Uranium Hexafluoride (DUF{sub 6}) Management Program evaluated alternatives for managing its inventory of DUF{sub 6} and issued the ''Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride'' (DUF{sub 6} PEIS) in April 1999 (DOE 1999). The DUF{sub 6} inventory is stored in cylinders at three DOE sites: Paducah, Kentucky; Portsmouth, Ohio; and East Tennessee Technology Park (ETTP), near Oak Ridge, Tennessee. In the Record of Decision for the DUF{sub 6} PEIS, DOE stated its decision to promptly convert the DUF{sub 6} inventory to a more stable chemical form. Subsequently, the U.S. Congress passed, and the President signed, the ''2002 Supplemental Appropriations Act for Further Recovery from and Response to Terrorist Attacks on the United States'' (Public Law No. 107-206). This law stipulated in part that, within 30 days of enactment, DOE must award a contract for the design, construction, and operation of a DUF{sub 6} conversion plant at the Department's Paducah, Kentucky, and Portsmouth, Ohio, sites, and for the shipment of DUF{sub 6} cylinders stored at ETTP to the Portsmouth site for conversion. This wetland assessment has been prepared by DOE, pursuant to Executive Order 11990 (''Protection of Wetlands'') and DOE regulations for implementing this Executive Order as set forth in Title 10, Part 1022, of the ''Code of Federal Regulations'' (10 CFR Part 1022 [Compliance with Floodplain and Wetland Environmental Review Requirements]), to evaluate potential impacts to wetlands from the construction and operation of a conversion facility at the DOE Portsmouth site. Approximately 0.02 acre (0.009 ha) of a 0.08-acre (0.03-ha) palustrine emergent wetland would likely be eliminated by direct placement of fill material during facility construction at Location A. Portions of this wetland that are not filled may be indirectly affected by an altered hydrologic regime because of the proximity of construction, possibly resulting in a decreased frequency or duration of inundation or soil saturation, and potential loss of hydrology necessary to sustain wetland conditions. Construction at Locations B or C would not result in direct impacts to wetlands. However, the hydrologic characteristics of nearby wetlands could be indirectly affected by adjacent construction. Executive Order 11990, ''Protection of Wetlands'', requires federal agencies to minimize the destruction, loss, or degradation of wetlands, and to preserve and enhance the natural and beneficial uses of wetlands. DOE regulations for implementing Executive Order 11990 are set forth in 10 CFR Part 1022. The impacts at Location A may potentially be avoided by an alternative routing of the entrance road, or mitigation may be developed in coordination with the appropriate regulatory agencies. Unavoidable impacts to wetlands that are within the jurisdiction of the USACE may require a CWA Section 404 Permit, which would trigger the requirement for a CWA Section 401 Water Quality Certification from the State of Ohio. Unavoidable impacts to isolated wetlands may require an Isolated Wetlands Permit from the Ohio Environmental Protection Agency. A mitigation plan may be required prior to the initiation of construction. Cumulative impacts to wetlands are anticipated to be negligible to minor for the proposed action, in conjunction with the effects of existing conditions and other activities. Habitat disturbance would involve settings commonly found in this part of Ohio, which in many cases involve previously disturbed habitats.

  11. An experimental test of the effect of plant functional group diversity on arthropod diversity

    Microsoft Academic Search

    Amy J. Symstad; Evan Siemann; John Haarstad

    2000-01-01

    Characteristics used to categorize plant species into functional groups for their effects on ecosystem functioning may also be relevant to higher trophic levels. In addition, plant and consumer diversity should be positively related because more diverse plant communities offer a greater variety of resources for the consumers. Thus, the functional group composition and richness of a plant community may affect

  12. Effects of elevated CO2 , nitrogen deposition, and decreased species diversity on foliar fungal plant disease

    E-print Network

    Crews, Stephen

    of the plant community in one year of a factorial grassland experiment. Decreased plant diversity had the broadest effect, increasing pathogen load across the plant community. Decreased diversity increased foliar fungal disease. Decreased plant diversity further magnified the increase in C3 grass pathogen load

  13. Metabolomics Unravel Contrasting Effects of Biodiversity on the Performance of Individual Plant Species

    Microsoft Academic Search

    Christian Scherling; Christiane Roscher; Patrick Giavalisco; Ernst-Detlef Schulze; Wolfram Weckwerth; Jerome Chave

    2010-01-01

    In spite of evidence for positive diversity-productivity relationships increasing plant diversity has highly variable effects on the performance of individual plant species, but the mechanisms behind these differential responses are far from being understood. To gain deeper insights into the physiological responses of individual plant species to increasing plant diversity we performed systematic untargeted metabolite profiling on a number of

  14. THE EFFECTS OF INTRASPECIFIC AND INTERSPECIFIC COMPETITION ON PLANT GROWTH

    Microsoft Academic Search

    Rashmi Jasrasaria; Debleena Mitra

    Competition between plants of the same species (wheat and wheat) and plants of different species (wheat and pea) was examined to determine an optimum seed density and whether two kinds of plants could be grown together. Different numbers of wheat seeds were planted per starting pot to test the impacts of intraspecific competition on an individual plant, and wheat seeds

  15. Evaluation of the immunomodulatory effects of five herbal plants.

    PubMed

    Amirghofran, Z; Azadbakht, M; Karimi, M H

    2000-09-01

    A group of medicinal plants including, Silybum marianum, Matricaria chamomilla, Calendula officinalis, Cichorium intybus and Dracocephalum kotschyi which grow in Iran, were extracted with ethanol 70% and the mitogenic activity was examined both on human peripheral blood lymphocytes and thymocytes. Effect of these extracts on proliferative responsiveness of human lymphocytes to phytohemagglutinin (PHA) and on the mixed lymphocyte reaction (MLR) was also investigated. The results obtained indicated that none of the extracts had a direct mitogenic effect on human lymphocytes or thymocytes (stimulation index, SI<0.07). Among the plants studied, C. intybus and C. officinalis showed a complete inhibitory effect on the proliferation of lymphocytes in the presence of PHA (SI range 0.01-0.49). A dose dependent inhibitory effect was obtained in the case of D. kotschyi. Extract of M. chamomilla showed almost no stimulatory effect. A significant decrease in proliferation assay due to 0.1-10 microg/ml of S. marianum was observed (SI<0.46, P<0.05). In MLR, a markedly stimulatory effect with some lower concentrations of all the extracts except Dracocephalum was detected. The highest stimulatory effect was due to 100 microg/ml of S. marianum (SI 2.82). Treatment of mixed lymphocytes with 0.1-10 microg/ml of C. officinalis (SI range 1.34-1.80) and 10 microg/ml of M. chamomilla and C. intybus (SI 2.18 and 1.70, respectively) strongly increased the cell proliferation. In conclusion, this in vitro study revealed the capacity of all the extracts except Dracocephalum to enhance the proliferation of lymphocytes after stimulation with the allogenic cells. PMID:10967468

  16. Effects of highway construction on stream water quality and macroinvertebrate condition in a Mid-Atlantic Highlands watershed, USA

    USGS Publications Warehouse

    Chen, Y.; Viadero, R.C., Jr.; Wei, X.; Fortney, R.; Hedrick, L.B.; Welsh, S.A.; Anderson, J.T.; Lin, L.-S.

    2009-01-01

    Refining best management practices (BMPs) for future highway construction depends on a comprehensive understanding of environmental impacts from current construction methods. Based on a before-after-control impact (BACI) experimental design, long-term stream monitoring (1997-2006) was conducted at upstream (as control, n = 3) and downstream (as impact, n = 6) sites in the Lost River watershed of the Mid-Atlantic Highlands region, West Virginia. Monitoring data were analyzed to assess impacts of during and after highway construction on 15 water quality parameters and macroinvertebrate condition using the West Virginia stream condition index (WVSCI). Principal components analysis (PCA) identified regional primary water quality variances, and paired t tests and time series analysis detected seven highway construction-impacted water quality parameters which were mainly associated with the second principal component. In particular, impacts on turbidity, total suspended solids, and total iron during construction, impacts on chloride and sulfate during and after construction, and impacts on acidity and nitrate after construction were observed at the downstream sites. The construction had statistically significant impacts on macroinvertebrate index scores (i.e., WVSCI) after construction, but did not change the overall good biological condition. Implementing BMPs that address those construction-impacted water quality parameters can be an effective mitigation strategy for future highway construction in this highlands region. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  17. Social aspects of technical progress in the carbonization industry and their realization in plant construction and overhaul projects

    Microsoft Academic Search

    A. N. Minasov; N. F. Simonov; B. V. Ivanov; M. V. Borodin

    1976-01-01

    The technical progress program for the Tenth Five-Year Plan period embraces the automation and mechanization of labor-intensive operations (particularly in coke-oven plants), the scrapping of worn-out and outmoded equipment, the centralization of maintenance services, the adoption of subassembly maintenance techniques, the improvement of labor management and organization structures (to conform to the norms for numbers of plant workers, qualified staff,

  18. HOST CHOICE BY APHIDIUS COLEMANI: EFFECTS OF PLANTS, PLANT-APHID COMBINATIONS AND THE PRESENCE OF INTRAGUILD PREDATORS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study first measured the effect of plant (radish, pepper and wheat), aphid-plant combination (the green peach aphid MYZUS PERSICAE on pepper and radish, and the bird cherry-oat aphid RHOPALOSIPHUM PADI on wheat) and the host on which A. COLEMANI was reared (the cotton aphid APHIS GOSSYPII on cu...

  19. Effects of invasive species on plant communities: an example using submersed aquatic plants at the regional level

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Submerged aquatic plants have a key role in maintaining functioning aquatic ecosystems through their effects in the hydrological regime, sedimentation, nutrient cycling and habitats of associated fauna. Modifications of aquatic plant communities, as for example through the introduction of invasive s...

  20. Contrasting Effects of Land Use Intensity and Exotic Host Plants on the Specialization of Interactions in Plant-Herbivore Networks

    PubMed Central

    de Araújo, Walter Santos; Vieira, Marcos Costa; Lewinsohn, Thomas M.; Almeida-Neto, Mário

    2015-01-01

    Human land use tends to decrease the diversity of native plant species and facilitate the invasion and establishment of exotic ones. Such changes in land use and plant community composition usually have negative impacts on the assemblages of native herbivorous insects. Highly specialized herbivores are expected to be especially sensitive to land use intensification and the presence of exotic plant species because they are neither capable of consuming alternative plant species of the native flora nor exotic plant species. Therefore, higher levels of land use intensity might reduce the proportion of highly specialized herbivores, which ultimately would lead to changes in the specialization of interactions in plant-herbivore networks. This study investigates the community-wide effects of land use intensity on the degree of specialization of 72 plant-herbivore networks, including effects mediated by the increase in the proportion of exotic plant species. Contrary to our expectation, the net effect of land use intensity on network specialization was positive. However, this positive effect of land use intensity was partially canceled by an opposite effect of the proportion of exotic plant species on network specialization. When we analyzed networks composed exclusively of endophagous herbivores separately from those composed exclusively of exophagous herbivores, we found that only endophages showed a consistent change in network specialization at higher land use levels. Altogether, these results indicate that land use intensity is an important ecological driver of network specialization, by way of reducing the local host range of herbivore guilds with highly specialized feeding habits. However, because the effect of land use intensity is offset by an opposite effect owing to the proportion of exotic host species, the net effect of land use in a given herbivore assemblage will likely depend on the extent of the replacement of native host species with exotic ones. PMID:25565141

  1. Contrasting effects of land use intensity and exotic host plants on the specialization of interactions in plant-herbivore networks.

    PubMed

    de Araújo, Walter Santos; Vieira, Marcos Costa; Lewinsohn, Thomas M; Almeida-Neto, Mário

    2015-01-01

    Human land use tends to decrease the diversity of native plant species and facilitate the invasion and establishment of exotic ones. Such changes in land use and plant community composition usually have negative impacts on the assemblages of native herbivorous insects. Highly specialized herbivores are expected to be especially sensitive to land use intensification and the presence of exotic plant species because they are neither capable of consuming alternative plant species of the native flora nor exotic plant species. Therefore, higher levels of land use intensity might reduce the proportion of highly specialized herbivores, which ultimately would lead to changes in the specialization of interactions in plant-herbivore networks. This study investigates the community-wide effects of land use intensity on the degree of specialization of 72 plant-herbivore networks, including effects mediated by the increase in the proportion of exotic plant species. Contrary to our expectation, the net effect of land use intensity on network specialization was positive. However, this positive effect of land use intensity was partially canceled by an opposite effect of the proportion of exotic plant species on network specialization. When we analyzed networks composed exclusively of endophagous herbivores separately from those composed exclusively of exophagous herbivores, we found that only endophages showed a consistent change in network specialization at higher land use levels. Altogether, these results indicate that land use intensity is an important ecological driver of network specialization, by way of reducing the local host range of herbivore guilds with highly specialized feeding habits. However, because the effect of land use intensity is offset by an opposite effect owing to the proportion of exotic host species, the net effect of land use in a given herbivore assemblage will likely depend on the extent of the replacement of native host species with exotic ones. PMID:25565141

  2. A demographic approach to study effects of climate change in desert plants

    PubMed Central

    Salguero-Gómez, Roberto; Siewert, Wolfgang; Casper, Brenda B.; Tielbörger, Katja

    2012-01-01

    Desert species respond strongly to infrequent, intense pulses of precipitation. Consequently, indigenous flora has developed a rich repertoire of life-history strategies to deal with fluctuations in resource availability. Examinations of how future climate change will affect the biota often forecast negative impacts, but these—usually correlative—approaches overlook precipitation variation because they are based on averages. Here, we provide an overview of how variable precipitation affects perennial and annual desert plants, and then implement an innovative, mechanistic approach to examine the effects of precipitation on populations of two desert plant species. This approach couples robust climatic projections, including variable precipitation, with stochastic, stage-structured models constructed from long-term demographic datasets of the short-lived Cryptantha flava in the Colorado Plateau Desert (USA) and the annual Carrichtera annua in the Negev Desert (Israel). Our results highlight these populations' potential to buffer future stochastic precipitation. Population growth rates in both species increased under future conditions: wetter, longer growing seasons for Cryptantha and drier years for Carrichtera. We determined that such changes are primarily due to survival and size changes for Cryptantha and the role of seed bank for Carrichtera. Our work suggests that desert plants, and thus the resources they provide, might be more resilient to climate change than previously thought. PMID:23045708

  3. R E S E A R C H A R T I C L E Effects of plant host species and plant community richness on

    E-print Network

    Weiblen, George D

    communities. Impacts of changing plant diversity on microbial com- munity composition have been documented regardless of the richness or diversity of the surrounding plant community, then the impacts of plantR E S E A R C H A R T I C L E Effects of plant host species and plant community richness

  4. Use of filler limestone and construction and demolition residues for remediating soils contaminated with heavy metals: an assessment by means of plant uptake.

    NASA Astrophysics Data System (ADS)

    Banegas, Ascension; Martinez-Sanchez, Maria Jose; Agudo, Ines; Perez-Sirvent, Carmen

    2010-05-01

    A greenhouse trial was carried out to evaluate the assimilation of heavy metals by three types of horticultural plants (lettuce, broccoli and alfalfa), different parts of which are destined for human and animal consumption (leaves, roots, fruits). The plants were cultivated in four types of soil, one uncontaminated (T1), one soil collected in the surrounding area of Sierra Minera (T2), the third being remediated with residues coming from demolition and construction activities (T3) and the four remediated with filler limestone (T4). To determine the metal content, soil samples were first ground to a fine powder using an agate ball mill. Fresh vegetable samples were separated into root and aboveground biomass and then lyophilized. The DTPA-extractable content was also determined to calculate the bioavailable amount of metal. Finally, the translocation factor (TF) and bioconcentration factor (BCF) were calculated. Arsenic levels were obtained by using atomic fluorescence spectrometry with an automated continuous flow hydride generation (HG-AFS) spectrometer and Cd, Pb and Zn was determined by electrothermal atomization atomic absorption spectrometry (ETAAS) or flame atomic absorption spectrometry (FAAS). Samples of the leached water were also obtained and analyzed. According to our results, the retention of the studied elements varies with the type of plant and is strongly decreased by the incorporation of filler limestone and/or construction and demolition residues to the soils. This practice represents a suitable way to reduce the risk posed to the biota by the presence of high levels of heavy metal in soil.

  5. DOE/EA-1517: Environmental Assessment for the Design and Construction of a Fuel Ethanol Plant, Jasper County, Indiana (April 2005)

    SciTech Connect

    N /A

    2005-04-29

    Based on action by the U.S. Congress, the U.S. Department of Energy (DOE) has funding available to support a proposal by the Iroquois Bio-energy Company (IBEC), an Indiana limited liability company, to construct a fuel ethanol plant in Jasper County, Indiana (the proposed plant). Congress has acknowledged the merit of this project by providing specific funding through DOE. Consequently, DOE proposes to provide partial funding to IBEC to subsidize the design and construction of the proposed plant (the Proposed Action). In accordance with DOE and National Environmental Policy Act (NEPA) implementing regulations, DOE is required to evaluate the potential environmental impacts of DOE facilities, operations, and related funding decisions. The proposal to use Federal funds to support the project requires DOE to address NEPA requirements and related environmental documentation and permitting requirements. In compliance with NEPA (42 U.S.C. {section} 4321 et seq.) and DOE's NEPA implementing regulations (10 CFR section 1021.330) and procedures, this environmental assessment (EA) examines the potential environmental impacts of DOE's Proposed Action and a No Action Alternative.

  6. Cotton Planting Date and Plant Population Effects on Yield and Quality in the Mississippi Delta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton producers in the Mississippi Delta plant in early spring, but wet, cold weather often develops then and may reduce plant population directly or indirectly. Producers must occasionally decide if replanting is necessary. The objective of these studies was to determine planting date and plant ...

  7. 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 ?l of 0.01 mM calliterpenone (8.0 ?g/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. PMID:23271460

  8. Ecological effects of transgene persistence on plant communities in the presence and absence of drift levels of glyphosate herbicide

    EPA Science Inventory

    In 2005, plant communities were constructed in outdoor sunlit chambers that contained 3 round tubs having a surface area of 1.2 m2 and a depth of 0.6 m. Six plant types were planted in triplicate using the same spatial arrangement in each tub. Three of the six plant types were se...

  9. Development of a Constructed Brackish Tidal Marsh and its Effect on Trace Metal Immobilization

    NASA Astrophysics Data System (ADS)

    ElBishlawi, H.

    2011-12-01

    Two tidal marshes along the Hackensack River in the New Jersey Meadowlands, one constructed and the other natural and well established, were characterized to determine and compare their ability to immobilize trace metals including as Cu, Cr, Pb, and Zn in their sediments. Pore-waters were sampled throughout the year, and sediment cores were collected to determine the dynamics of trace metals in sediments and their interactions with redox active species such as iron and sulfide as well as organic matter. Precipitation of metals with sulfides played a major factor in immobilizing certain metals including Pb and Zn. However, the constructed marsh, which exhibited lower dissolved sulfide concentrations, but higher dissolved iron species, removed certain dissolved trace metals including Zn and Pb more effectively than the established marsh. At both sites, the presence of sulfide did not result in the expected precipitation of elements such as Cu and Zn with sulfide and a small dissolved concentration these metals was detectable in the sediment pore water. These trace metals exhibited an association with heterogeneous dissolved organic matter, which was further confirmed through thermodynamic equilibrium modeling. The constructed high marsh immobilized the most trace metals in the region where sulfide produced through sulfate reduction reacted with but had not yet been completely titrated out of solution by dissolved iron. Additionally, the intermittently oxic/anoxic tidal zone of the high marsh removed more metals than the permanently inundated low marsh due to its higher tidal water exchange. Building constructed wetlands that maximize intertidal high marsh areas may optimize trace metal immobilization.

  10. Grassland Plant Composition Alters Vehicular Disturbance Effects in Kansas, USA

    NASA Astrophysics Data System (ADS)

    Dickson, Timothy L.; Wilsey, Brian J.; Busby, Ryan R.; Gebhart, Dick L.

    2008-05-01

    Many “natural” areas are exposed to military or recreational off-road vehicles. The interactive effects of different types of vehicular disturbance on vegetation have rarely been examined, and it has been proposed that some vegetation types are less susceptible to vehicular disturbance than others. At Fort Riley, Kansas, we experimentally tested how different plant community types changed after disturbance from an M1A1 Abrams tank driven at different speeds and turning angles during different seasons. The greatest vegetation change was observed because of driving in the spring in wet soils and the interaction of turning while driving fast (vegetation change was measured with Bray-Curtis dissimilarity). We found that less vegetation change occurred in communities with high amounts of native prairie vegetation than in communities with high amounts of introduced C3 grasses, which is the first experimental evidence we are aware of that suggests plant communities dominated by introduced C3 grasses changed more because of vehicular disturbance than communities dominated by native prairie grasses. We also found that vegetation changed linearly with vehicular disturbance intensity, suggesting that at least initially there was no catastrophic shift in vegetation beyond a certain disturbance intensity threshold. Overall, the intensity of vehicular disturbance appeared to play the greatest role in vegetation change, but the plant community type also played a strong role and this should be considered in land use planning. The reasons for greater vegetation change in introduced C3 grass dominated areas deserve further study.

  11. Herbivore effects on plant species density at varying productivity levels

    USGS Publications Warehouse

    Gough, L.; Grace, J.B.

    1998-01-01

    Artificially increasing primary productivity decreases plant species richness in many habitats; herbivory may affect this outcome, but it has rarely been directly addressed in fertilization studies. This experiment was conducted in two Louisiana coastal marshes to examine the effects of nutrient enrichment and sediment addition on herbaceous plant communities with and without vertebrate herbivory. After three growing seasons, fertilization increased community biomass in all plots, but decreased species density (the number of species per unit area) only in plots protected from herbivory. Herbivory alone did not alter species density at either site. At the brackish marsh, herbivory caused a shift in dominance in the fertilized plots from a species that is considered the competitive dominant, but is selectively eaten, to another less palatable species. At the fresh marsh, increased dead biomass in the absence of herbivory and in the fertilized plots probably contributed to the decrease in species density, perhaps by limiting germination of annuals. Our results support those of other fertilization studies in which plant species density decreases with increased biomass, but only in those plots protected from herbivory.

  12. Planting date and genotype effects on components of corn yield

    E-print Network

    Rubottom, Bradley Gene

    1986-01-01

    dates in 1984 compared to 1985, while the opposite was true for the later plant- ed dates . The first three planting dates generally took significantly more time to emerge than the three later planting dates. Heat units accumulated to 50% emergence... decreased as planting dates were delayed, and heat units were highly correlated with emergence rates. Planting date delays decreased the vegetative stage by 0. 95 days for each 1-day delay in planting. Heat unit accumulations to 50% silk- ing generally...

  13. The effects of plant density upon pollination success, reproductive effort and fruit parasitism in Cistus ladanifer L. (Cistaceae)

    E-print Network

    The effects of plant density upon pollination success, reproductive effort and fruit parasitism different determinants of plant reproductive success. We simultaneously recorded individual plant for plant populations should recognize that reproductive success is the accumulated result of several

  14. Energetic cost of web construction and its effect on web relocation in the web-building spider Agelena limbata

    Microsoft Academic Search

    Koichi Tanaka

    1989-01-01

    Although spider webs may be effective in trapping prey, they require energy for construction. The design of webs varies in complexity from species to species. I assume that the energetic cost of web construction is significantly different among web types or species. This cost may constrain foraging tactics, particularly web relocation, because web relocation also requires energy to make a

  15. Seasonal temperature and power plant chlorination effects on estuarine invertebrates.

    PubMed

    Margrey, S L; Burton, D T; Hall, L W

    1981-11-01

    The influence of seasonal temperatures (15-22 degrees C) on chlorine (0.00, 0.15 and 0.30 mg/L total residual chlorine), delta T (2, 6 and 10 degrees C), and exposure duration (0.08, 2.0 and 4.0 hr) interaction studies simulating power plant entrainment and effluent discharge conditions was evaluated for opossum shrimp. Neomysis americana and amphipods, Gammarus Seasonal Temperature was an important factor effecting the toxicity of the three treatment variables with both of these organisms. Mortality responses were greater at the higher acclimation temperatures. PMID:7325688

  16. Drought effect on plant nitrogen and phosphorus: a meta-analysis.

    PubMed

    He, Mingzhu; Dijkstra, Feike A

    2014-12-01

    Climate change scenarios forecast increased aridity in large areas worldwide with potentially important effects on nutrient availability and plant growth. Plant nitrogen and phosphorus concentrations (plant [N] and [P]) have been used to assess nutrient limitation, but a comprehensive understanding of drought stress on plant [N] and [P] remains elusive. We conducted a meta-analysis to examine responses of plant [N] and [P] to drought manipulation treatments and duration of drought stress. Drought stress showed negative effects on plant [N] (-3.73%) and plant [P] (-9.18%), and a positive effect on plant N:P (+ 6.98%). Drought stress had stronger negative effects on plant [N] and [P] in the short term (< 90 d) than in the long term (> 90 d). Drought treatments that included drying-rewetting cycles showed no effect on plant [N] and [P], while constant, prolonged, or intermittent drought stress had a negative effect on plant [P]. Our results suggest that negative effects on plant [N] and [P] are alleviated with extended duration of drought treatments and with drying-rewetting cycles. Availability of water, rather than of N and P, may be the main driver for reduced plant growth with increased long-term drought stress. PMID:25130263

  17. Bottom-up effects of host-plant species diversity and top-down effects of ants

    E-print Network

    Mooney, Kailen A.

    Bottom-up effects of host-plant species diversity and top-down effects of ants interactively, Galicia, Spain While plant diversity is well known to increase primary productivity, whether these bottom whether pine tree species diversity, aphid-tending ants and their interaction determined plant performance

  18. Functional immobilization of plant receptor-like kinase onto microbeads towards receptor array construction and receptor-based ligand fishing.

    PubMed

    Shinohara, Hidefumi; Matsubayashi, Yoshikatsu

    2007-10-01

    Despite the large number of receptor-like kinases (RLKs) in plants, few of their specific ligands are known. Ligand fishing is one of the most challenging post-genomic technologies. Here, we report a strategy for functional immobilization of plant RLKs on microbeads via covalent linkage. Because of the high density of immobilized RLKs, ligand-receptor interaction can be visualized at high sensitivity using fluorescent-labeled ligands under the confocal laser scanning microscope. Moreover, using a receptor-based affinity chromatography system with RLK microbeads, the ligand of the receptor was directly retrieved at high purity from complex natural samples. Our RLK microbeads and receptor-based ligand fishing approach is a feasible alternative to conventional forward genetics and bioassay-based biochemical purification for identification of novel ligand-receptor pairs in plants. PMID:17662033

  19. Floral herbivore effect on the sex expression of an andromonoecious plant, Isomeris arborea (Capparaceae)

    Microsoft Academic Search

    Gary A. Krupnick; Arthur E. Weis

    1998-01-01

    Flower-feeding insects may influence the reproductive behavior of their host plant. In plants with labile sex expression, the ratio of maternal to paternal investment may change in response to damage, an effect that goes beyond the direct reduction of plant gametes. We examined the effects of floral herbivory by the beetle Meligethes rufimanus (Nitidulidae) on the ratio of hermaphroditic flowers

  20. 27 CFR 19.723 - Effect of redistillation on plant size and bond amount.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Effect of redistillation on plant size and bond amount. 19.723 Section...TREASURY LIQUORS DISTILLED SPIRITS PLANTS Distilled Spirits for Fuel Use Redistillation...19.723 Effect of redistillation on plant size and bond amount. The...

  1. 27 CFR 19.723 - Effect of redistillation on plant size and bond amount.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Effect of redistillation on plant size and bond amount. 19.723 Section...TREASURY ALCOHOL DISTILLED SPIRITS PLANTS Distilled Spirits for Fuel Use Redistillation...19.723 Effect of redistillation on plant size and bond amount. The...

  2. 27 CFR 19.723 - Effect of redistillation on plant size and bond amount.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Effect of redistillation on plant size and bond amount. 19.723 Section...TREASURY ALCOHOL DISTILLED SPIRITS PLANTS Distilled Spirits for Fuel Use Redistillation...19.723 Effect of redistillation on plant size and bond amount. The...

  3. Live Specimens More Effective than World Wide Web for Learning Plant Material

    ERIC Educational Resources Information Center

    Taraban, Roman; McKenney, Cynthia; Peffley, Ellen; Applegarth, Ashley

    2004-01-01

    The World Wide Web and other computer-based media are new teaching resources for plant identification. The purpose of the experiments reported here was to test whether learning plant identification for woody and herbaceous plant material over the web was as effective, more effective, or preferred by undergraduate students when compared with…

  4. Differential Effects of Typha Litter and Plants on Invasive Lythrum Salicaria Seedling Survival and Growth

    Microsoft Academic Search

    Heather A. Hager

    2004-01-01

    Invasive species are a problem because of their detrimental ecological and economic effects. Increased disturbance caused by human impacts is hypothesized as a primary factor promoting the spread of invaders. Plants and plant litter can have important effects on plant colonization and community composition by affecting seedling survival and growth. I examined the hypothesis that invasion of non-native Lythrum salicaria

  5. Comparison between polishing (maturation) ponds and subsurface flow constructed wetlands (planted and unplanted) for the post-treatment of the effluent from UASB reactors.

    PubMed

    von Sperling, M; Dornelas, F L; Assunção, F A L; de Paoli, A C; Mabub, M O A

    2010-01-01

    This paper presents the results of a comparison of the performance of two treatment systems operating in parallel, with the same influent wastewater. The investigated systems are (i) UASB + three polishing ponds in series + coarse filter (200 population equivalents) and (ii) UASB + subsurface flow constructed wetlands (50 population equivalents). Two wetland units, operating in parallel, were analysed, being one planted (Typha latifolia) and the other unplanted. The systems were located in Belo Horizonte, Brazil. The wetland systems showed to be more efficient in the removal of organic matter and suspended solids, leading to good effluent BOD and COD concentrations and excellent SS concentrations. The planted wetland performed better than the unplanted unit, but the latter was also able to provide a good effluent quality. The polishing pond system was more efficient in the removal of nitrogen (ammonia) and coliforms (E. coli). Land requirements and cost considerations are presented. PMID:20220242

  6. Construction and operation of a one ton per hour pilot plant for the VEW coal conversion process

    NASA Astrophysics Data System (ADS)

    Poller, J.

    1981-11-01

    The pilot plant is based on airblown partial gasification in an entrained reactor. Results show that at temperatures of about 1450 C, 55% to 65% of the feed coal, and 70% to 80% of the sulfur can be converted into product gas. The quality of the low BTU gas is sufficient for application in the combined gas-stream turbine process. Extensive knowledge is also gained concerning gas accompanying pollutants and the behavior of different brickwork materials in the reactor environment. The acquired data allows proper dimensioning of a prototype plant.

  7. Spatially complex neighboring relationships among grassland plant species as an effective mechanism of defense against herbivory

    Microsoft Academic Search

    Ling Wang; Deli Wang; Yuguang Bai; Yue Huang; Meng Fan; Jushan Liu; Yexing Li

    2010-01-01

    Close spatial relationships between plant species are often important for defense against herbivory. The associational plant\\u000a defense may have important implications for plant community structure, species diversity, and species coexistence. An increasing\\u000a number of studies have focused on associational plant defense against herbivory at the scale of the individual plant and its\\u000a nearest neighbors. However, the average neighborhood effects between

  8. Treatment of industrial wastewater with two-stage constructed wetlands planted with Typha latifolia and Phragmites australis

    Microsoft Academic Search

    Cristina S. C. Calheiros; António O. S. S. Rangel; Paula M. L. Castro

    2009-01-01

    Industrial wastewater treatment comprises several processes to fulfill the discharge permits or to enable the reuse of wastewater. For tannery wastewater, constructed wetlands (CWs) may be an interesting treatment option. Two-stage series of horizontal subsurface flow CWs with Phragmites australis (UP series) and Typha latifolia (UT series) provided high removal of organics from tannery wastewater, up to 88% of biochemical

  9. Using Project Performance to Measure Effectiveness of Quality Management System Maintenance and Practices in Construction Industry

    PubMed Central

    Leong, Tiong Kung; Ariff, Mohd. Shoki Md.

    2014-01-01

    This paper proposed seven existing and new performance indicators to measure the effectiveness of quality management system (QMS) maintenance and practices in construction industry. This research is carried out with a questionnaire based on QMS variables which are extracted from literature review and project performance indicators which are established from project management's theory. Data collected was analyzed using correlation and regression analysis. The findings indicate that client satisfaction and time variance have positive and significant relationship with QMS while other project performance indicators do not show significant results. Further studies can use the same project performance indicators to study the effectiveness of QMS in different sampling area to improve the generalizability of the findings. PMID:24701182

  10. Watershed Ecology and the Effects of Construction on Erosion and Water Quality

    NSDL National Science Digital Library

    Norman Leonard (Pike High School)

    2007-08-01

    The purpose of the lab is to allow middle and high school students to begin to understand their place in their watershed, explore erosion, water quality assessment and the impact of construction sites through both field work and inquiry-based experiments. Students should have prior knowledge of the water cycle. Upon completion of this activity, students will be able to describe the impact that erosion has on water quality, including the effects of soil types and potential effects of the watershed. This teaching resource was developed by a K-12 science teacher in the American Physiological SocietyÂ?s 2007 Frontiers in Physiology Program. For more information on this program, please visit www.frontiersinphys.org.

  11. Effect of amphotericin B nanodisks on plant fungal diseases

    PubMed Central

    Pérez-de-Luque, Alejandro; Cifuentes, Zuny; Beckstead, Jennifer A; Sillero, Josefina C; Ávila, Carmen; Rubio, Josefa; Ryan, Robert O

    2013-01-01

    BACKGROUND The development of water-soluble nanodevices extends the potential use of compounds developed for other purposes (e.g. antifungal drugs or antibiotics) for applications in agriculture. For example, the broad-spectrum, water-insoluble, macrolide polyene antibiotic amphotericin B(AMB) could be used to inhibit phytopathogenic fungi. A new formulation embedding AMB in nanodisks (NDs) enhances antibiotic solubility and confers protection against environmental damage. In the present study, AMB-NDs were tested for efficacy against several phytopathogenic fungi in vitro and on infected living plants (chickpea and wheat). RESULTS Compared with AMB in dimethylsulfoxide (DMSO), AMB-NDs increased the sensitivity of several fungal species to this antimycotic in vitro. Sensitivity varied with fungal species as well as with the forma specialis. Phytophthora cinnamomi, previously reported as insensitive to other polyene antimycotics, remained unaffected at the doses examined. Some effect against disease symptoms were obtained with AMB-NDs against fusarium wilt in chickpea, whereas the results were highly variable in wheat, depending on both the species and treatment regimen. CONCLUSION The results confirm that formulation of AMB into ND increases its effectiveness against phytopathogenic fungi in vitro, opening the possibility for its use on infected plants in the field. PMID:21710554

  12. Plant-derived health: the effects of turmeric and curcuminoids.

    PubMed

    Bengmark, S; Mesa, M D; Gil, A

    2009-01-01

    Plants contain numerous polyphenols, which have been shown to reduce inflammation and hereby to increase resistance to disease. Examples of such polyphenols are isothiocyanates in cabbage and broccoli, epigallocatechin in green tee, capsaicin in chili peppers, chalones, rutin and naringenin in apples, resveratrol in red wine and fresh peanuts and curcumin/curcuminoids in turmeric. Most diseases are maintained by a sustained discreet but obvious increased systemic inflammation. Many studies suggest that the effect of treatment can be improved by a combination of restriction in intake of proinflammatory molecules such as advanced glycation end products (AGE), advanced lipoperoxidation end products (ALE), and rich supply of antiinflammatory molecules such as plant polyphenols. To the polyphenols with a bulk of experimental documentation belong the curcuminoid family and especially its main ingredient, curcumin. This review summarizes the present knowledge about these turmericderived ingredients, which have proven to be strong antioxidants and inhibitors of cyclooxigenase-2 (COX-2), lipoxygenase (LOX) and nuclear factor kappa B (NF-kappaB) but also AGE. A plethora of clinical effects are reported in various experimental diseases, but clinical studies in humans are few. It is suggested that supply of polyphenols and particularly curcuminoids might be value as complement to pharmaceutical treatment, but also prebiotic treatment, in conditions proven to be rather therapy-resistant such as Crohn's, long-stayed patients in intensive care units, but also in conditions such as cancer, liver cirrhosis, chronic renal disease, chronic obstructive lung disease, diabetes and Alzheimer's disease. PMID:19721899

  13. Women in Construction Management: Identification of the Most Effective Factors in Attracting and Retaining Freshmen and Sophomore Level Students

    E-print Network

    Mathew, Minna

    2014-08-06

    are most effective in attracting and retaining female students in CM degree programs based on surveys administered to 40 female CM freshmen and sophomore students in five selected universities. Awareness of career opportunities in the construction industry...

  14. Effective Automated Feature Construction and Selection for Classification of Biological Sequences

    PubMed Central

    Kamath, Uday; De Jong, Kenneth; Shehu, Amarda

    2014-01-01

    Background Many open problems in bioinformatics involve elucidating underlying functional signals in biological sequences. DNA sequences, in particular, are characterized by rich architectures in which functional signals are increasingly found to combine local and distal interactions at the nucleotide level. Problems of interest include detection of regulatory regions, splice sites, exons, hypersensitive sites, and more. These problems naturally lend themselves to formulation as classification problems in machine learning. When classification is based on features extracted from the sequences under investigation, success is critically dependent on the chosen set of features. Methodology We present an algorithmic framework (EFFECT) for automated detection of functional signals in biological sequences. We focus here on classification problems involving DNA sequences which state-of-the-art work in machine learning shows to be challenging and involve complex combinations of local and distal features. EFFECT uses a two-stage process to first construct a set of candidate sequence-based features and then select a most effective subset for the classification task at hand. Both stages make heavy use of evolutionary algorithms to efficiently guide the search towards informative features capable of discriminating between sequences that contain a particular functional signal and those that do not. Results To demonstrate its generality, EFFECT is applied to three separate problems of importance in DNA research: the recognition of hypersensitive sites, splice sites, and ALU sites. Comparisons with state-of-the-art algorithms show that the framework is both general and powerful. In addition, a detailed analysis of the constructed features shows that they contain valuable biological information about DNA architecture, allowing biologists and other researchers to directly inspect the features and potentially use the insights obtained to assist wet-laboratory studies on retainment or modification of a specific signal. Code, documentation, and all data for the applications presented here are provided for the community at http://www.cs.gmu.edu/~ashehu/?q=OurTools. PMID:25033270

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

    Microsoft Academic Search

    C. M. Macal; B. J. Broomfield

    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

  16. Belowground biodiversity effects of plant symbionts support aboveground productivity

    E-print Network

    Bruns, Tom

    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. These results also indicate that belowground diversity may act as insurance for maintaining plant productivity

  17. Rootstock effects on plant vigor and watermelon fruit quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon (Citrullus lanatus var. lanatus) plants were grown in Lane, Oklahoma. Fruit weight, dimensions, and quality (SSC, firmness, lycopene content) of seeded and seedless varieties were measured. Watermelons from vigorous plants (determined by plant length, width, and a visual estimate of plant...

  18. Effects of an industrial effluent on plant colonization and on the germination and post-germinative growth of seeds of terrestrial and aquatic plant species.

    PubMed

    Crowe, A U; Plant, A L; Kermode, A R

    2002-01-01

    Major oil sands industrial companies are located in the Athabasca Oil Sands Deposit in northeastern Alberta, Canada. During the process used to extract light crude oil (via hot water digestion and flotation), gypsum is usually added to produce consolidated tails (CT) and CT release water. The vast volumes of process-treated waters (effluent) are held within large dyked tailings ponds. Toward testing viable options for reclamation, various hummock-wetlands systems have been constructed; in addition, natural wetlands (inhabited by obligate wetland plant species) have become established as a result of seeping of the effluents held within the large dyked ponds. Vegetation surveys conducted on and around the industrial site revealed that the constructed wetlands associated with the dyke drainage (effluent treated with phosphorous) and consolidated tails (CT; effluent treated with gypsum) had low biodiversity and were not invaded by many aquatic plants. Although the natural wetland was also not invaded by many aquatic species, it was found to be as diverse as the reference wetlands (i.e. off-site wetlands not exposed to the effluents). Exposure to oil sands effluents had an inhibitory effect on the germination (percent and/or rate) of several plant species (tomato, clover, wheat, rye, pea, reed canary grass, loblolly pine); clover and tomato seed germination were most affected. Two treatments in particular (effluents from the natural on-site wetland and the CT constructed wetland), delayed germination, and also led to reduced fresh weight of seedlings of tomato, wheat, clover and loblolly pine. The osmolarities of the effluents associated with the natural on-site wetland and CT constructed wetland were 712 and 728 mOs/kg, respectively; substituting these effluents with solutions of polyethylene glycol of the same osmotic potentials had a greater inhibitory effect on germination rate. The negative effects of the effluents on seed germination may account for the paucity of aquatic species that invaded the oil sands impacted wetlands. This factor will also be critical in determining the long-term feasibility of hummock-wetland systems. PMID:11843534

  19. Species richness in a successional grassland: effects of nitrogen enrichment and plant litter

    E-print Network

    Foster, Bryan L.; Gross, Katherine L.

    1998-12-01

    We conducted a field experiment in a successional grassland to investigate the short-term effects of nitrogen enrichment and plant litter on plant species richness and on the establishment of a native grass (Andropogon gerardi...

  20. Effects of mammalian herbivore declines on plant communities: observations and experiments in an

    E-print Network

    Miller, Thomas E.

    Effects of mammalian herbivore declines on plant communities: observations and experiments, CA 95616, USA Summary 1. Herbivores in uence the structure and composition of terrestrial plant conditions, herbivore identity and herbivore abundance. As anthropogenic impacts continue to drive large